WorldWideScience

Sample records for brainstem response abr

  1. Abnormal Auditory Brainstem Response (ABR Findings in a Near-Normal Hearing Child with Noonan Syndrome

    Directory of Open Access Journals (Sweden)

    Bahram Jalaei

    2017-01-01

    Full Text Available Introduction: Noonan syndrome (NS is a heterogeneous genetic disease that affects many parts of the body. It was named after Dr. Jacqueline Anne Noonan, a paediatric cardiologist.Case Report: We report audiological tests and auditory brainstem response (ABR findings in a 5-year old Malay boy with NS. Despite showing the marked signs of NS, the child could only produce a few meaningful words. Audiological tests found him to have bilateral mild conductive hearing loss at low frequencies. In ABR testing, despite having good waveform morphology, the results were atypical. Absolute latency of wave V was normal but interpeak latencies of wave’s I-V, I-II, II-III were prolonged. Interestingly, interpeak latency of waves III-V was abnormally shorter.Conclusion:Abnormal ABR results are possibly due to abnormal anatomical condition of brainstem and might contribute to speech delay.

  2. Comparing auditory brainstem responses (ABRs) to toneburst and narrow band CE-chirp in young infants.

    Science.gov (United States)

    Rodrigues, Gabriela Ribeiro Ivo; Ramos, Natália; Lewis, Doris Ruthi

    2013-09-01

    The difference of characteristics (latency and amplitude) between toneburst and narrow CE-chirp stimuli on ABR recording was analyzed in normal hearing infants. 500, 1000, 2000 and 4000 Hz toneburst and narrow band CE-chirp auditory brainstem responses (ABRs) were recorded in 40 normal-hearing infants. The amplitude and latency parameters of the ABR were collected for each of the four stimulus levels: 80, 60, 40, and 20 dB nHL. Both stimuli started from 80 dB nHL using alternating polarity and the rates were both 27.1/s. The toneburst latencies are greater than narrow band CE-chirp latencies for all intensities at 500, 1000 and 2000 Hz (p Hz this difference was not significant. At 500 Hz, wave V amplitude is larger for toneburst than narrow CE-chirp (p Hz there is no difference between the wave V toneburst and narrow band CE-chirp amplitudes at 80 dB nHL (p = 0.940; p = 0.776 and p = 0.217 respectively). On the other hand, in the levels to 60, 40 and 20 dB nHL, narrow band CE-chirp amplitudes are larger than toneburst amplitude (p < 0.001). Narrow band CE-chirp ABRs generates shorter latencies than the toneburst ABRs, especially to low frequencies. Higher amplitudes were found with narrow band CE-chirp stimuli for all frequencies tested, except to high levels. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  3. A Cochlear Implant Performance Prognostic Test Based on Electrical Field Interactions Evaluated by eABR (Electrical Auditory Brainstem Responses.

    Directory of Open Access Journals (Sweden)

    Nicolas Guevara

    Full Text Available Cochlear implants (CIs are neural prostheses that have been used routinely in the clinic over the past 25 years. They allow children who were born profoundly deaf, as well as adults affected by hearing loss for whom conventional hearing aids are insufficient, to attain a functional level of hearing. The "modern" CI (i.e., a multi-electrode implant using sequential coding strategies has yielded good speech comprehension outcomes (recognition level for monosyllabic words about 50% to 60%, and sentence comprehension close to 90%. These good average results however hide a very important interindividual variability as scores in a given patients' population often vary from 5 to 95% in comparable testing conditions. Our aim was to develop a prognostic model for patients with unilateral CI. A novel method of objectively measuring electrical and neuronal interactions using electrical auditory brainstem responses (eABRs is proposed.The method consists of two measurements: 1 eABR measurements with stimulation by a single electrode at 70% of the dynamic range (four electrodes distributed within the cochlea were tested, followed by a summation of these four eABRs; 2 Measurement of a single eABR with stimulation from all four electrodes at 70% of the dynamic range. A comparison of the eABRs obtained by these two measurements, defined as the monaural interaction component (MIC, indicated electrical and neural interactions between the stimulation channels. Speech recognition performance without lip reading was measured for each patient using a logatome test (64 "vowel-consonant-vowel"; VCV; by forced choice of 1 out of 16. eABRs were measured in 16 CI patients (CIs with 20 electrodes, Digisonic SP; Oticon Medical ®, Vallauris, France. Significant correlations were found between speech recognition performance and the ratio of the amplitude of the V wave of the eABRs obtained with the two measurements (Pearson's linear regression model, parametric correlation: r

  4. Processamento auditivo e potenciais evocados auditivos de tronco cerebral (BERA Auditory precessing and auditory brainstem response (ABR

    Directory of Open Access Journals (Sweden)

    Marcela Pfeiffer

    2009-01-01

    Full Text Available OBJETIVO: verificar relação existente entre os potenciais auditivos de tronco cerebral e a avaliação comportamental do processamento auditivo. MÉTODOS: foi realizada em um grupo de 60 meninas residentes de Paraíba do Sul na idade de nove a 12 anos com limiares tonais dentro dos padrões de normalidade e timpanometria tipo A com presença dos reflexos acústicos. Os testes utilizados para a avaliação comportamental do processamento auditivo foram: avaliação simplificada do processamento auditivo, teste de fala no ruído, teste de dissílabos alternados e teste dicótico não verbal. Após a avaliação do processamento auditivo, as crianças foram subdivididas em dois grupos, G1 (sem alteração no processamento auditivo e G2 (com alteração no processamento auditivo e submetidas aos potenciais auditivos de tronco cerebral. Os parâmetros utilizados na comparação dos dois grupos foram: latência absoluta das ondas I, III e V; latência interpicos das ondas I-III, I-V, III-V; diferença interaural da latência interpico I-V; e diferença interaural da latência da onda V. RESULTADOS: foram encontradas diferenças estatísticas nos parâmetros de latência interpico das ondas I-V na orelha esquerda (p=0,009, diferença interaural da latência interpico de ondas I-V (p=0,020 e diferença da latência interpico de ondas I e V da orelha direita para a esquerda entre os grupos G1 e G2 (p=0,025. CONCLUSÃO: foi possível encontrar relação dos potenciais evocados auditivos de tronco cerebral com a avaliação comportamental do processamento auditivo nos parâmetros de latência interpico entre as ondas I e V da orelha esquerda e diferença interaural da latência interpico I-V na orelha esquerda.PURPOSE: to investigate the correlation of auditory brainstem response (ABR and behavioral auditory processing evaluation. METHODS: sixty girls, from Paraíba do Sul, ranging from 9 to 12-year-old were evaluated. In order to take part in the study

  5. Role of cervical vestibular evoked myogenic potentials (cVEMP and auditory brainstem response (ABR in the evaluation of vestibular schwannoma

    Directory of Open Access Journals (Sweden)

    Deepa Aniket Valame

    Full Text Available Abstract Introduction: Cervical vestibular evoked myogenic potentials (cVEMP can assess the integrity of the inferior vestibular nerve thereby promising to be a useful tool in the audiological test battery to diagnose vestibular schwannoma. Objective: To ascertain the utility of cVEMP in diagnosis of vestibular schwannoma in conjunction with the ABR and to evaluate whether the size of lesion has any effect on the cVEMP measures. Methods: Case-files of 15 known cases of vestibular schwannoma whose pure tone audiometry, auditory brainstem response (ABR, cVEMP and radiological investigation findings were available, were included in the study. Patients were categorised as large or small tumours based on the size. The absolute and inter-peak latencies of ABR, amplitudes of waves V and I, and inter-aural latency difference of wave V of ABR; and latency of P1 and N1 of cVEMP and amplitude of P1-N1 complex were considered in the study. Results: There were eight large and nine small tumours. All the patients with large tumours showed significant severity of hearing loss whereas only three out of nine patients with small tumours showed severe to profound deafness in the affected ear. The rest showed hearing status ranging from normal hearing sensitivity to moderate hearing loss. Most of the patients with large tumours showed complete absence of ABR in the affected ears with no identifiable wave-peaks. ABR in small tumours exhibited delayed III-I and delayed V-I interpeak latency interval (IPL. Four out of five patients with large unilateral tumours revealed contralateral effects of reduced amplitude or absence of cVEMP. On the contrary, six out of eight unilateral small tumours showed a normal cVEMP response in the contralateral ear. Both the patients with NF2 in the present study demonstrated cVEMP abnormalities. Conclusion: ABR and cVEMP, when used in combination, can be of immense use in identification of neuro-otologic conditions such as vestibular

  6. Hearing threshold assessment in young children with electrocochleography (EcochG) and auditory brainstem responses (ABR): experience at the University Hospital of Ferrara.

    Science.gov (United States)

    Aimoni, C; Ciorba, A; Bovo, R; Trevisi, P; Busi, M; Martini, A

    2010-10-01

    Electrophysiological evaluation is a fundamental procedure for the diagnostic assessment of hearing loss during infancy; in these cases, information concerning threshold level and auditory perception is particularly useful to establish a correct hearing rehabilitation program (hearing aids and cochlear implants). Purpose of this study is to underline the role of auditory brainstem responses (ABR) and electrocochleography (EcochG) in the definition of hearing loss in a selected group of children, referred to the Audiology Department of the University Hospital of Ferrara, for a tertiary level audiological assessment. A retrospective study of the paediatric patient database at the Audiology Department of the University Hospital of Ferrara has been performed. In a period between January 2000 and December 2007, a total of 272 paediatric cases have been identified (544 ears). An EM 12 Mercury apparatus has been used for the electrophysiological threshold identification (ABR and EcochG). Recordings were carried out under general anaesthesia, in a protected enviroment. In 19 of the 272 paediatric cases selected--38 ears (7%), the results of threshold evaluation through ABR were uncertain. The Ecochg recording resulted crucial for the final diagnosis in terms of definition of the hearing threshold level, and it was then possible to ensure the better hearing rehabilitation strategy. ABR has to be considered the first choice in hearing assessment strategy, either for screening or for diagnosis in newborns as well as in non-collaborating children; ECochG still may be considered a reliable diagnostic tool. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  7. Presbycusis and auditory brainstem responses: a review

    Directory of Open Access Journals (Sweden)

    Shilpa Khullar

    2011-06-01

    Full Text Available Age-related hearing loss or presbycusis is a complex phenomenon consisting of elevation of hearing levels as well as changes in the auditory processing. It is commonly classified into four categories depending on the cause. Auditory brainstem responses (ABRs are a type of early evoked potentials recorded within the first 10 ms of stimulation. They represent the synchronized activity of the auditory nerve and the brainstem. Some of the changes that occur in the aging auditory system may significantly influence the interpretation of the ABRs in comparison with the ABRs of the young adults. The waves of ABRs are described in terms of amplitude, latencies and interpeak latency of the different waves. There is a tendency of the amplitude to decrease and the absolute latencies to increase with advancing age but these trends are not always clear due to increase in threshold with advancing age that act a major confounding factor in the interpretation of ABRs.

  8. Influence of two-electrode montages on the level-specific (LS) CE-Chirp auditory brainstem response (ABR) at multiple intensity levels.

    Science.gov (United States)

    Dzulkarnain, Ahmad Aidil Arafat; Noor Ibrahim, Siti Hajra Mu'minah; Anuar, Nur Farah Aida; Abdullah, Siti Aisyah; Tengku Zam Zam, Tengku Zulaila Hasma; Rahmat, Sarah; Mohd Ruzai, Muhammad Amar

    2017-10-01

    To investigate the influence of two different electrode montages (ipsilateral: reference to mastoid and vertical: reference to nape of neck) to the ABR results recorded using a level-specific (LS)-CE-Chirp® in normally hearing subjects at multiple intensities levels. Quasi-experimental and repeated measure study designs were applied in this study. Two different stopping criteria were used, (1) a fixed-signal averaging 4000 sweeps and, (2) a minimum quality indicator of Fmp = 3.1 with a minimum of 800 sweeps. Twenty-nine normally hearing adults (18 females, 11 male) participated. Wave V amplitudes were significantly larger in the LS CE-Chirp® recorded from the vertical montage than the ipsilateral montage. Waves I and III amplitudes were significantly larger from the ipsilateral LS CE-Chirp® than from the other montages and stimulus combinations. The differences in the quality of the ABR recording between the vertical and ipsilateral montages were marginal. Overall, the result suggested that the vertical LS CE-Chirp® ABR had a high potential for a threshold-seeking application, because it produced a higher wave V amplitude. The Ipsilateral LS CE-Chirp® ABR, on the other hand, might also have a high potential for the site of lesion application, because it produced larger waves I and III amplitudes.

  9. Ipsilateral and Contralateral Auditory Brainstem Response Reorganization in Hemispherectomized Patients

    Directory of Open Access Journals (Sweden)

    Ning Yao

    2013-01-01

    Full Text Available Background. Cortical hemispherectomy leads to degeneration of ipsilateral subcortical structures, which can be observed long term after the operation. Therefore, reorganization of the brainstem auditory pathway might occur. The aim of this study was to assess reorganization of brainstem auditory pathways by measuring the auditory brainstem response (ABR in long-term hemispherectomized patients. Methods. We performed bilateral monaural stimulation and measured bilateral ABR in 8 patients ~20 years after hemispherectomy and 10 control subjects. Magnetic resonance imaging (MRI was performed in patients to assess structural degeneration. Results. All patients showed degenerated ipsilateral brainstem structures by MRI but no significant differences in bilateral recording ABR wave latencies. However, nonsurgical-side stimulation elicited significantly longer wave V latencies compared to surgical-side stimulation. Differences in bilateral ABR were observed between hemispherectomized patients and control subjects. Waves III and V latencies elicited by nonsurgical-side stimulation were significantly longer than those in control subjects; surgical-side stimulation showed no significant differences. Conclusions. (1 Differences in ABR latency elicited by unilateral stimulation are predominantly due to bilateral brainstem auditory pathway activity rather than to changes in brainstem volume; (2 ABR Waves III and V originate predominantly in the contralateral brainstem; and (3 subcortical auditory pathways appear to reorganize after long term hemispherectomy.

  10. Effects of Caffeine on Auditory Brainstem Response

    OpenAIRE

    Saleheh Soleimanian; Saeed Farahani; Mansoureh Adel Ghahraman; Dr. Abbas Kebriaiezadeh; Dr. Soghrat Faghihzadeh

    2008-01-01

    Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR).Materials and Methods: In this clinical trial study 43 nor...

  11. Auditory Brainstem Responses to Continuous Natural Speech in Human Listeners.

    Science.gov (United States)

    Maddox, Ross K; Lee, Adrian K C

    2018-01-01

    Speech is an ecologically essential signal, whose processing crucially involves the subcortical nuclei of the auditory brainstem, but there are few experimental options for studying these early responses in human listeners under natural conditions. While encoding of continuous natural speech has been successfully probed in the cortex with neurophysiological tools such as electroencephalography (EEG) and magnetoencephalography, the rapidity of subcortical response components combined with unfavorable signal-to-noise ratios signal-to-noise ratio has prevented application of those methods to the brainstem. Instead, experiments have used thousands of repetitions of simple stimuli such as clicks, tone-bursts, or brief spoken syllables, with deviations from those paradigms leading to ambiguity in the neural origins of measured responses. In this study we developed and tested a new way to measure the auditory brainstem response (ABR) to ongoing, naturally uttered speech, using EEG to record from human listeners. We found a high degree of morphological similarity between the speech-derived ABRs and the standard click-evoked ABR, in particular, a preserved Wave V, the most prominent voltage peak in the standard click-evoked ABR. Because this method yields distinct peaks that recapitulate the canonical ABR, at latencies too short to originate from the cortex, the responses measured can be unambiguously determined to be subcortical in origin. The use of naturally uttered speech to measure the ABR allows the design of engaging behavioral tasks, facilitating new investigations of the potential effects of cognitive processes like language and attention on brainstem processing.

  12. Automatic hearing loss detection system based on auditory brainstem response

    International Nuclear Information System (INIS)

    Aldonate, J; Mercuri, C; Reta, J; Biurrun, J; Bonell, C; Gentiletti, G; Escobar, S; Acevedo, R

    2007-01-01

    Hearing loss is one of the pathologies with the highest prevalence in newborns. If it is not detected in time, it can affect the nervous system and cause problems in speech, language and cognitive development. The recommended methods for early detection are based on otoacoustic emissions (OAE) and/or auditory brainstem response (ABR). In this work, the design and implementation of an automated system based on ABR to detect hearing loss in newborns is presented. Preliminary evaluation in adults was satisfactory

  13. The auditory brainstem response in two lizard species

    DEFF Research Database (Denmark)

    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong

    2010-01-01

    Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal...... animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform...

  14. Auditory brainstem response – a valid and cost-effective screening tool for vestibular schwannoma?

    DEFF Research Database (Denmark)

    Rafique, Irfan; Wennervaldt, Kasper; Melchiors, Jacob

    2016-01-01

    Abstract: Conclusion: Contemporary auditory brainstem response (ABR) is not valid as a screening tool for VS, when considering the sensitivity of 80%, the specificity of 77%, and the positive predictive value of 3.4%, MRI screening is superior to ABR in Denmark when considering cost-effectiveness......Abstract: Conclusion: Contemporary auditory brainstem response (ABR) is not valid as a screening tool for VS, when considering the sensitivity of 80%, the specificity of 77%, and the positive predictive value of 3.4%, MRI screening is superior to ABR in Denmark when considering cost...

  15. Accuracy of averaged auditory brainstem response amplitude and latency estimates

    DEFF Research Database (Denmark)

    Madsen, Sara Miay Kim; M. Harte, James; Elberling, Claus

    2017-01-01

    Objective: The aims were to 1) establish which of the four algorithms for estimating residual noise level and signal-to-noise ratio (SNR) in auditory brainstem responses (ABRs) perform better in terms of post-average wave-V peak latency and amplitude errors and 2) determine whether SNR or noise...

  16. Test-retest consistency of speech-evoked auditory brainstem responses in typically-developing children

    OpenAIRE

    Hornickel, Jane; Knowles, Erica; Kraus, Nina

    2011-01-01

    The click-evoked auditory brainstem response (ABR) is widely used in clinical settings, partly due to its predictability and high test-retest consistency. More recently, the speech-evoked ABR has been used to evaluate subcortical processing of complex signals, allowing for the objective assessment of biological processes underlying auditory function and auditory processing deficits not revealed by responses to clicks. Test-retest reliability of some components of speech-evoked ABRs has been s...

  17. Speech Evoked Auditory Brainstem Response in Stuttering

    Directory of Open Access Journals (Sweden)

    Ali Akbar Tahaei

    2014-01-01

    Full Text Available Auditory processing deficits have been hypothesized as an underlying mechanism for stuttering. Previous studies have demonstrated abnormal responses in subjects with persistent developmental stuttering (PDS at the higher level of the central auditory system using speech stimuli. Recently, the potential usefulness of speech evoked auditory brainstem responses in central auditory processing disorders has been emphasized. The current study used the speech evoked ABR to investigate the hypothesis that subjects with PDS have specific auditory perceptual dysfunction. Objectives. To determine whether brainstem responses to speech stimuli differ between PDS subjects and normal fluent speakers. Methods. Twenty-five subjects with PDS participated in this study. The speech-ABRs were elicited by the 5-formant synthesized syllable/da/, with duration of 40 ms. Results. There were significant group differences for the onset and offset transient peaks. Subjects with PDS had longer latencies for the onset and offset peaks relative to the control group. Conclusions. Subjects with PDS showed a deficient neural timing in the early stages of the auditory pathway consistent with temporal processing deficits and their abnormal timing may underlie to their disfluency.

  18. Effects of Caffeine on Auditory Brainstem Response

    Directory of Open Access Journals (Sweden)

    Saleheh Soleimanian

    2008-06-01

    Full Text Available Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR.Materials and Methods: In this clinical trial study 43 normal 18-25 years old male students were participated. The subjects consumed 0, 2 and 3 mg/kg BW caffeine in three different sessions. Auditory brainstem responses were recorded before and 30 minute after caffeine consumption. The results were analyzed by Friedman and Wilcoxone test to assess the effects of caffeine on auditory brainstem response.Results: Compared to control group the latencies of waves III,V and I-V interpeak interval of the cases decreased significantly after 2 and 3mg/kg BW caffeine consumption. Wave I latency significantly decreased after 3mg/kg BW caffeine consumption(p<0.01. Conclusion: Increasing of the glutamate level resulted from the adenosine receptor blocking brings about changes in conduction in the central auditory pathway.

  19. Clinical Experience of Auditory Brainstem Response Testing on Pediatric Patients in the Operating Room

    Directory of Open Access Journals (Sweden)

    Guangwei Zhou

    2012-01-01

    Full Text Available Objectives. To review our experience of conducting auditory brainstem response (ABR test on children in the operating room and discuss the benefits versus limitations of this practice. Methods. Retrospective review study conducted in a pediatric tertiary care facility. A total of 267 patients identified with usable data, including ABR results, medical and surgical notes, and follow-up evaluation. Results. Hearing status successfully determined in all patients based on the ABR results form the operating room. The degrees and the types of hearing loss also documented in most of the cases. In addition, multiple factors that may affect the outcomes of ABR in the operating room identified. Conclusions. Hearing loss in children with complicated medical issues can be accurately evaluated via ABR testing in the operating room. Efforts should be made to eliminate adverse factors to ABR recording, and caution should be taken when interpreting ABR results from the operating room.

  20. Modeling auditory evoked brainstem responses to transient stimuli

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Dau, Torsten; Harte, James

    2012-01-01

    A quantitative model is presented that describes the formation of auditory brainstem responses (ABR) to tone pulses, clicks and rising chirps as a function of stimulation level. The model computes the convolution of the instantaneous discharge rates using the “humanized” nonlinear auditory......-nerve (AN) model of Zilany and Bruce (2007) and an empirically derived unitary response function which is assumed to reflect contributions from different cell populations within the auditory brainstem, recorded at a given pair of electrodes on the scalp. It is shown that the model accounts for the decrease...

  1. Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

    Directory of Open Access Journals (Sweden)

    J. Tillein

    2012-01-01

    Full Text Available To compare the development of the auditory system in hearing and completely acoustically deprived animals, naive congenitally deaf white cats (CDCs and hearing controls (HCs were investigated at different developmental stages from birth till adulthood. The CDCs had no hearing experience before the acute experiment. In both groups of animals, responses to cochlear implant stimulation were acutely assessed. Electrically evoked auditory brainstem responses (E-ABRs were recorded with monopolar stimulation at different current levels. CDCs demonstrated extensive development of E-ABRs, from first signs of responses at postnatal (p.n. day 3 through appearance of all waves of brainstem response at day 8 p.n. to mature responses around day 90 p.n.. Wave I of E-ABRs could not be distinguished from the artifact in majority of CDCs, whereas in HCs, it was clearly separated from the stimulus artifact. Waves II, III, and IV demonstrated higher thresholds in CDCs, whereas this difference was not found for wave V. Amplitudes of wave III were significantly higher in HCs, whereas wave V amplitudes were significantly higher in CDCs. No differences in latencies were observed between the animal groups. These data demonstrate significant postnatal subcortical development in absence of hearing, and also divergent effects of deafness on early waves II–IV and wave V of the E-ABR.

  2. Brainstem response to speech and non-speech stimuli in children with learning problems.

    Science.gov (United States)

    Malayeri, Saeed; Lotfi, Yones; Moossavi, Seyed Abdollah; Rostami, Reza; Faghihzadeh, Soghrat

    2014-07-01

    Neuronal firing synchronization is critical for recording auditory responses from the brainstem. Recent studies have shown that both click and/da/synthetic syllable (speech) stimuli perform well in evoking neuronal synchronization at the brainstem level. In the present study, brainstem responses to click and speech stimuli were compared between children with learning problems (LP) and those with normal learning (NL) abilities. The study included 49 children with LP and 34 children with NL. Auditory brainstem response (ABR) to 100-μs click stimulus and speech ABR (sABR) to/da/40-ms stimulus were tested in these children. Wave latencies III, V, and Vn and inter-peak latency (IPL) V-Vn in click ABR and wave latencies I, V, and A and IPL V-A in sABR were significantly longer in children with LP than children with NL. Except IPL of I-III, a significant positive correlation was observed between click ABR and sABR wave latencies and IPLs in children with NL; this correlation was weaker or not observed in children with LP. In this regard, the difference between correlation coefficients of wave latencies I, III, and V and IPLs I-V and V-Vn/V-A was significant in the two groups. Deficits in auditory processing timing in children with LP may have probably affected ABR for both click and speech stimuli. This finding emphasizes the possibility of shared connections between processing timing for speech and non-speech stimuli in auditory brainstem pathways. Weak or no correlation between click and speech ABR parameters in children with LP may have a clinical relevance and may be effectively used for objective diagnoses after confirming its sufficient sensitivity and specificity and demonstrating its acceptable validity with more scientific evidence. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Auditory brainstem response in two children with autism.

    Science.gov (United States)

    Coutinho, Miguel B; Rocha, Virgínia; Santos, M Carmo

    2002-10-21

    Autism develops before 30 months of age. Autistic disorder is characterized by a qualitative impairment in verbal and non verbal communication, in imaginative activity, and in reciprocal social interactions. Communication in autism is so strikingly impaired that the function of the hearing system has been under study over the past 30 years, namely after the advent of physiological assessment of hearing with the auditory brainstem response (ABR). Many research studies were developed to study ABR in autism as they constitute a direct test of both hearing status and integrity of brainstem pathways, but the results obtained are contradictory. The authors present case reports of two children with autistic disorder, 2 and 4 years of age, in which the ABR findings document a prevalent Peak I in the four ears tested. This characteristic configuration in ABR has not been previously reported and future work is needed to establish the importance of this finding and its implications in the awareness of the auditory status in these children.

  4. The auditory brainstem response in two lizard species.

    Science.gov (United States)

    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong; Carr, Catherine; Dooling, Robert J

    2010-08-01

    Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform in response to click stimulation showed one prominent and several smaller peaks occurring within 10 ms of the stimulus onset. ABRs to brief tone bursts revealed that geckos and anoles were most sensitive between 1.6-2 kHz and had similar hearing sensitivity up to about 5 kHz (thresholds typically 20-50 dB SPL). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than in most bird species.

  5. Test-retest consistency of speech-evoked auditory brainstem responses in typically-developing children.

    Science.gov (United States)

    Hornickel, Jane; Knowles, Erica; Kraus, Nina

    2012-02-01

    The click-evoked auditory brainstem response (ABR) is widely used in clinical settings, partly due to its predictability and high test-retest consistency. More recently, the speech-evoked ABR has been used to evaluate subcortical processing of complex signals, allowing for the objective assessment of biological processes underlying auditory function and auditory processing deficits not revealed by responses to clicks. Test-retest reliability of some components of speech-evoked ABRs has been shown for adults and children over the course of months. However, a systematic study of the consistency of the speech-evoked brainstem response in school-age children has not been conducted. In the present study, speech-evoked ABRs were collected from 26 typically-developing children (ages 8-13) at two time points separated by one year. ABRs were collected for /da/ presented in quiet and in a 6-talker babble background noise. Test-retest consistency of response timing, spectral encoding, and signal-to-noise ratio was assessed. Response timing and spectral encoding were highly replicable over the course of one year. The consistency of response timing and spectral encoding found for the speech-evoked ABRs of typically-developing children suggests that the speech-evoked ABR may be a unique tool for research and clinical assessment of auditory function, particularly with respect to auditory-based communication skills. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Searching for the optimal stimulus eliciting auditory brainstem responses in humans

    DEFF Research Database (Denmark)

    Fobel, Oliver; Dau, Torsten

    2004-01-01

    This study examines auditory brainstem responses (ABR) elicited by rising frequency chirps. Two chirp stimuli were developed and designed such as to compensate for cochlear travel-time differences across frequency, in order to maximize neural synchrony. One chirp, referred to as the O-chirp, was ......This study examines auditory brainstem responses (ABR) elicited by rising frequency chirps. Two chirp stimuli were developed and designed such as to compensate for cochlear travel-time differences across frequency, in order to maximize neural synchrony. One chirp, referred to as the O...

  7. Auditory brainstem response in gas station attendants.

    Science.gov (United States)

    Quevedo, Lenita da Silva; Tochetto, Tania; Siqueira, Marcia Amaral; Machado, Márcia Salgado

    2012-12-01

    Ototoxicity of organic solvents can affect the hearing system up to the cochlea level and the central structures of hearing. To evaluate the neurophysiological integrity of the hearing system in subjects exposed to fuels using ABR. Prospective study. We evaluated attendants from three gas stations in Santa Maria/RS. The sample had 21 subjects, who were evaluated by auditory brainstem response. We found an alteration in the absolute latencies of Waves I and III and in all the interpeak latencies, in the right ear. In the left ear there was a change in the absolute latencies of all Waves, and in all the interpeak intervals. A change in the interaural difference of Wave V was found in 19% of the individuals. In the group exposed for more than five years, there were subjects with a statistically significant changes: in the I-V interpeak of the right ear; in the absolute latency of Wave I and in the III-V interpeak of the left year. Exposure to fuels can cause alterations in the central hearing system.

  8. Low-frequency versus high-frequency synchronisation in chirp-evoked auditory brainstem responses

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Gøtsche-Rasmussen, Kristian

    2011-01-01

    This study investigates the frequency specific contribution to the auditory brainstem response (ABR) of chirp stimuli. Frequency rising chirps were designed to compensate for the cochlear traveling wave delay, and lead to larger wave-V amplitudes than for click stimuli as more auditory nerve fibres...

  9. Comparison of cochlear delay estimates using otoacoustic emissions and auditory brainstem responses

    DEFF Research Database (Denmark)

    Harte, James; Pigasse, Gilles; Dau, Torsten

    2009-01-01

    Different attempts have been made to directly measure frequency specific basilar membrane (BM) delays in animals, e.g., laser velocimetry of BM vibrations and auditory nerve fiber recordings. The present study uses otoacoustic emissions (OAEs) and auditory brainstem responses (ABRs) to estimate BM...

  10. Association Between Sex and Speech Auditory Brainstem Responses in Adults, and Relationship to Sex Hormone Levels.

    Science.gov (United States)

    Liu, Jinfeng; Wang, Dan; Li, Xiaoting; Ningyu, Wang

    2017-05-14

    BACKGROUND The aim of this study was to investigate the association between sex and speech-ABR in adults, and its relationship to sex hormone levels. MATERIAL AND METHODS Speech-ABR were elicited with the consonant-vowel syllable (/da/) in a total of 35 adults. Reproductive hormone levels were also measured. RESULTS The transient response of the speech-ABR (waves V, A, and O) in females show a shorter latency (waves V, A and O) and a larger amplitude (waves V and A) than in males (P0.05). The sustained response of females exhibited a larger amplitude (wave F, P0.05). The latencies of speech-ABR were positively correlated with testosterone level (P0.05). The E2 showed a positive correlation with the absolute value of amplitude of the speech-ABR (P speech-ABR (P0.05). CONCLUSIONS Sex differences in speech-ABR are significant in adults. The latencies and amplitude of the speech-ABR waves were correlated with the E2 concentration and testosterone level. The sex hormones likely affect speech encoding in the brainstem.

  11. Speech-evoked auditory brainstem responses in children with hearing loss.

    Science.gov (United States)

    Koravand, Amineh; Al Osman, Rida; Rivest, Véronique; Poulin, Catherine

    2017-08-01

    The main objective of the present study was to investigate subcortical auditory processing in children with sensorineural hearing loss. Auditory Brainstem Responses (ABRs) were recorded using click and speech/da/stimuli. Twenty-five children, aged 6-14 years old, participated in the study: 13 with normal hearing acuity and 12 with sensorineural hearing loss. No significant differences were observed for the click-evoked ABRs between normal hearing and hearing-impaired groups. For the speech-evoked ABRs, no significant differences were found for the latencies of the following responses between the two groups: onset (V and A), transition (C), one of the steady-state wave (F), and offset (O). However, the latency of the steady-state waves (D and E) was significantly longer for the hearing-impaired compared to the normal hearing group. Furthermore, the amplitude of the offset wave O and of the envelope frequency response (EFR) of the speech-evoked ABRs was significantly larger for the hearing-impaired compared to the normal hearing group. Results obtained from the speech-evoked ABRs suggest that children with a mild to moderately-severe sensorineural hearing loss have a specific pattern of subcortical auditory processing. Our results show differences for the speech-evoked ABRs in normal hearing children compared to hearing-impaired children. These results add to the body of the literature on how children with hearing loss process speech at the brainstem level. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Age and Gender Effects On Auditory Brain Stem Response (ABR

    Directory of Open Access Journals (Sweden)

    Yones Lotfi

    2012-10-01

    Full Text Available Objectives: Auditory Brain Stem Response (ABR is a result of eight nerve and brain stem nuclei stimulation. Several factors may affect the latencies, interpeak latencies and amplitudes in ABR especially sex and age. In this study, age and sex influence on ABR were studied. Methods: This study was performed on 120 cases (60 males and 60 females at Akhavan rehabilitation center of university of welfare and rehabilitation sciences, Tehran, Iran. Cases were divided in three age groups: 18-30, 31-50 and 51-70 years old. Each age group consists of 20 males and 20 females. Age and sex influences on absolute latency of wave I and V, and IPL of I-V were examined. Results: Independent t test showed that females have significantly shorter latency of wave I, V, and IPL I-V latency (P<0.001 than males. Two way ANOVA showed that latency of wave I, V and IPL I-V in 51-70 years old group was significantly higher than 18-30 and 31-50 years old groups (P<0.001 Discussion: According to the results of present study and similar studies, in clinical practice, different norms for older adults and both genders should be established.

  13. Unraveling the Mystery of Auditory Brainstem Response Corrections: The Need for Universal Standards.

    Science.gov (United States)

    Norrix, Linda W; Velenovsky, David

    The auditory brainstem response (ABR) is used to estimate behavioral hearing thresholds in infants and difficult-to-test populations. Differences between the toneburst ABR and behavioral thresholds exist making the correspondence between the two measures less than perfect. Some authors have suggested that corrections be applied to ABR thresholds to account for these differences. However, because there is no agreed upon universal standard, confusion regarding the use of corrections exists. The primary purpose of this article is to review the reasoning behind and use of corrections when the toneburst ABR is employed to estimate behavioral hearing thresholds. We also discuss other considerations that all audiologists should be aware of when obtaining and reporting ABR test results. A review of the purpose and use of corrections reveals no consensus as to whether they should be applied or which should be used. Additionally, when ABR results are adjusted, there is no agreement as to whether additional corrections for hearing loss or the age of the client are necessary. This lack of consensus can be confusing for all individuals working with hearing-impaired children and their families. Toneburst ABR thresholds do not perfectly align with behavioral hearing thresholds. Universal protocols for the use of corrections are needed. Additionally, evidence-based procedures must be employed to obtain valid ABRs that will accurately estimate hearing thresholds. American Academy of Audiology

  14. Measuring hearing in the harbor seal (Phoca vitulina): Comparison of behavioral and auditory brainstem response techniques

    Science.gov (United States)

    Wolski, Lawrence F.; Anderson, Rindy C.; Bowles, Ann E.; Yochem, Pamela K.

    2003-01-01

    Auditory brainstem response (ABR) and standard behavioral methods were compared by measuring in-air audiograms for an adult female harbor seal (Phoca vitulina). Behavioral audiograms were obtained using two techniques: the method of constant stimuli and the staircase method. Sensitivity was tested from 0.250 to 30 kHz. The seal showed good sensitivity from 6 to 12 kHz [best sensitivity 8.1 dB (re 20 μPa2.s) RMS at 8 kHz]. The staircase method yielded thresholds that were lower by 10 dB on average than the method of constant stimuli. ABRs were recorded at 2, 4, 8, 16, and 22 kHz and showed a similar best range (8-16 kHz). ABR thresholds averaged 5.7 dB higher than behavioral thresholds at 2, 4, and 8 kHz. ABRs were at least 7 dB lower at 16 kHz, and approximately 3 dB higher at 22 kHz. The better sensitivity of ABRs at higher frequencies could have reflected differences in the seal's behavior during ABR testing and/or bandwidth characteristics of test stimuli. These results agree with comparisons of ABR and behavioral methods performed in other recent studies and indicate that ABR methods represent a good alternative for estimating hearing range and sensitivity in pinnipeds, particularly when time is a critical factor and animals are untrained.

  15. Auditory Brainstem Responses and EMFs Generated by Mobile Phones.

    Science.gov (United States)

    Khullar, Shilpa; Sood, Archana; Sood, Sanjay

    2013-12-01

    There has been a manifold increase in the number of mobile phone users throughout the world with the current number of users exceeding 2 billion. However this advancement in technology like many others is accompanied by a progressive increase in the frequency and intensity of electromagnetic waves without consideration of the health consequences. The aim of our study was to advance our understanding of the potential adverse effects of GSM mobile phones on auditory brainstem responses (ABRs). 60 subjects were selected for the study and divided into three groups of 20 each based on their usage of mobile phones. Their ABRs were recorded and analysed for latency of waves I-V as well as interpeak latencies I-III, I-V and III-V (in ms). Results revealed no significant difference in the ABR parameters between group A (control group) and group B (subjects using mobile phones for maximum 30 min/day for 5 years). However the latency of waves was significantly prolonged in group C (subjects using mobile phones for 10 years for a maximum of 30 min/day) as compared to the control group. Based on our findings we concluded that long term exposure to mobile phones may affect conduction in the peripheral portion of the auditory pathway. However more research needs to be done to study the long term effects of mobile phones particularly of newer technologies like smart phones and 3G.

  16. Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants.

    Science.gov (United States)

    Keefe, Douglas H; Gorga, Michael P; Jesteadt, Walt; Smith, Lynette M

    2008-03-01

    In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the right ear in infant auditory brainstem responses (ABRs). The present study analyzed 2640 infant responses to further explore these effects. Ear differences in OAE SNR, signal, and noise were evaluated separately and across frequencies (1.5, 2, 3, and 4 kHz), and ABR asymmetries were compared with cochlear asymmetries. Analyses of ear-canal reflectance and admittance showed that asymmetries in middle-ear functioning did not explain cochlear and brainstem asymmetries. Current results are consistent with earlier studies showing right-ear dominance for TEOAE and ABR. Noise levels were higher in the right ear for OAEs and ABRs, causing ear asymmetries in SNR to differ from those in signal level. No left-ear dominance for DPOAE signal was observed. These results do not support a theory that ear asymmetries in cochlear processing mimic hemispheric brain specialization for auditory processing.

  17. The impact of degree of hearing loss on auditory brainstem response predictions of behavioral thresholds.

    Science.gov (United States)

    McCreery, Ryan W; Kaminski, Jan; Beauchaine, Kathryn; Lenzen, Natalie; Simms, Kendell; Gorga, Michael P

    2015-01-01

    Diagnosis of hearing loss and prescription of amplification for infants and young children require accurate estimates of ear- and frequency-specific behavioral thresholds based on auditory brainstem response (ABR) measurements. Although the overall relationship between ABR and behavioral thresholds has been demonstrated, the agreement is imperfect, and the accuracy of predictions of behavioral threshold based on ABR may depend on degree of hearing loss. Behavioral thresholds are lower than ABR thresholds, at least in part due to differences in calibration interacting with the effects of temporal integration, which are manifest in behavioral measurements but not ABR measurements and depend on behavioral threshold. Listeners with sensory hearing loss exhibit reduced or absent temporal integration, which could impact the relationship between ABR and behavioral thresholds as degree of hearing loss increases. The present study evaluated the relationship between ABR and behavioral thresholds in infants and children over a range of hearing thresholds, and tested an approach for adjusting the correction factor based on degree of hearing loss as estimated by ABR measurements. A retrospective review of clinical records was completed for 309 ears of 177 children with hearing thresholds ranging from normal to profound hearing loss and for whom both ABR and behavioral thresholds were available. Children were required to have the same middle ear status at both evaluations. The relationship between ABR and behavioral thresholds was examined. Factors that potentially could affect the relationship between ABR and behavioral thresholds were analyzed, including degree of hearing loss observed on the ABR, behavioral test method (visual reinforcement, conditioned play, or conventional audiometry), the length of time between ABR and behavioral assessments, and clinician-reported reliability of the behavioral assessment. Predictive accuracy of a correction factor based on the difference

  18. Effect of Infant Prematurity on Auditory Brainstem Response at Preschool Age

    Directory of Open Access Journals (Sweden)

    Sara Hasani

    2013-03-01

    Full Text Available Introduction: Preterm birth is a risk factor for a number of conditions that requires comprehensive examination. Our study was designed to investigate the impact of preterm birth on the processing of auditory stimuli and brain structures at the brainstem level at a preschool age.   Materials and Methods: An auditory brainstem response (ABR test was performed with low rates of stimuli in 60 children aged 4 to 6 years. Thirty subjects had been born following a very preterm labor or late-preterm labor and 30 control subjects had been born following a full-term labor.   Results: Significant differences in the ABR test result were observed in terms of the inter-peak intervals of the I–III and III–V waves, and the absolute latency of the III wave (P

  19. Evaluation of an auditory brainstem response in icteric neonates

    Directory of Open Access Journals (Sweden)

    Ahmad Talebian

    2017-08-01

    Full Text Available Background: Neonatal hyperbilirubinemia is a common and preventable cause of sensory-neural hearing impairment, which can cause difficulties in the development of speech and communication. This study was conducted to detect the toxic effect of hyperbilirubinemia on the brain stem and auditory tract in neonates with icterus admitted to Shahid Beheshti Hospital in Kashan, Iran. Materials and Methods: This cross-sectional study was conducted on 98 neonates with increased indirect bilirubin admitted to Shahid Beheshti Hospital in Kashan during 2014-2015. The patients were referred to Matini Hospital for the assessment of the auditory brainstem response (ABR; wave latency and interpeak intervals of the waves were also evaluated. According to the serum bilirubin level, the neonates were allocated into two groups; one group had a serum bilirubin level of 13-20 mg/d and another group had a bilirubin level more than 20 mg/d. Results: From 98 neonates, 26 (26.5% had a bilirubin level more than 20 mg/d and 72 (73.5% had a bilirubin level of 13-20 mg/d. Also, 46.1% of the neonates in the first group (bilirubin20 mg/d can cause an auditory processing disorder in neonates. So, performing ABR for screening and early detection of bilirubin toxicity can be recommended as a necessary audiologic intervention in all cases of severe neonatal hyperbilirubinemia.

  20. [Comparison of tone burst evoked auditory brainstem responses with different filter settings for referral infants after hearing screening].

    Science.gov (United States)

    Diao, Wen-wen; Ni, Dao-feng; Li, Feng-rong; Shang, Ying-ying

    2011-03-01

    Auditory brainstem responses (ABR) evoked by tone burst is an important method of hearing assessment in referral infants after hearing screening. The present study was to compare the thresholds of tone burst ABR with filter settings of 30 - 1500 Hz and 30 - 3000 Hz at each frequency, figure out the characteristics of ABR thresholds with the two filter settings and the effect of the waveform judgement, so as to select a more optimal frequency specific ABR test parameter. Thresholds with filter settings of 30 - 1500 Hz and 30 - 3000 Hz in children aged 2 - 33 months were recorded by click, tone burst ABR. A total of 18 patients (8 male/10 female), 22 ears were included. The thresholds of tone burst ABR with filter settings of 30 - 3000 Hz were higher than that with filter settings of 30 - 1500 Hz. Significant difference was detected for that at 0.5 kHz and 2.0 kHz (t values were 2.238 and 2.217, P Hz was smoother than that with filter settings of 30 - 3000 Hz at the same stimulus intensity. Response curve of the latter appeared jagged small interfering wave. The filter setting of 30 - 1500 Hz may be a more optimal parameter of frequency specific ABR to improve the accuracy of frequency specificity ABR for infants' hearing assessment.

  1. Abnormal auditory forward masking pattern in the brainstem response of individuals with Asperger syndrome

    Directory of Open Access Journals (Sweden)

    Johan Källstrand

    2010-05-01

    Full Text Available Johan Källstrand1, Olle Olsson2, Sara Fristedt Nehlstedt1, Mia Ling Sköld1, Sören Nielzén21SensoDetect AB, Lund, Sweden; 2Department of Clinical Neuroscience, Section of Psychiatry, Lund University, Lund, SwedenAbstract: Abnormal auditory information processing has been reported in individuals with autism spectrum disorders (ASD. In the present study auditory processing was investigated by recording auditory brainstem responses (ABRs elicited by forward masking in adults diagnosed with Asperger syndrome (AS. Sixteen AS subjects were included in the forward masking experiment and compared to three control groups consisting of healthy individuals (n = 16, schizophrenic patients (n = 16 and attention deficit hyperactivity disorder patients (n = 16, respectively, of matching age and gender. The results showed that the AS subjects exhibited abnormally low activity in the early part of their ABRs that distinctly separated them from the three control groups. Specifically, wave III amplitudes were significantly lower in the AS group than for all the control groups in the forward masking condition (P < 0.005, which was not the case in the baseline condition. Thus, electrophysiological measurements of ABRs to complex sound stimuli (eg, forward masking may lead to a better understanding of the underlying neurophysiology of AS. Future studies may further point to specific ABR characteristics in AS individuals that separate them from individuals diagnosed with other neurodevelopmental diseases.Keywords: asperger syndrome, auditory brainstem response, forward masking, psychoacoustics

  2. The auditory brainstem response to complex sounds: a potential biomarker for guiding treatment of psychosis

    Directory of Open Access Journals (Sweden)

    Melissa A Tarasenko

    2014-10-01

    Full Text Available Cognitive deficits limit psychosocial functioning in schizophrenia. For many patients, cognitive remediation approaches have yielded encouraging results. Nevertheless, therapeutic response is variable, and outcome studies consistently identify individuals who respond minimally to these interventions. Biomarkers that can assist in identifying patients likely to benefit from particular forms of cognitive remediation are needed. Here we describe an event-related potential (ERP biomarker – the auditory brainstem response to complex sounds (cABR – that appears to be particularly well-suited for predicting response to at least one form of cognitive remediation that targets auditory information processing. Uniquely, the cABR quantifies the fidelity of sound encoded at the level of the brainstem and midbrain. This ERP biomarker has revealed auditory processing abnormalities in various neurodevelopmental disorders, correlates with functioning across several cognitive domains, and appears to be responsive to targeted auditory training. We present preliminary cABR data from 18 schizophrenia patients and propose further investigation of this biomarker for predicting and tracking response to cognitive interventions.

  3. Click-evoked auditory brainstem responses and autism spectrum disorder: A meta-analytic review.

    Science.gov (United States)

    Talge, Nicole M; Tudor, Brooke M; Kileny, Paul R

    2018-03-30

    Behavior does not differentiate ASD risk prior to 12 months of age, but biomarkers may inform risk before symptoms emerge. Click-evoked auditory brainstem responses (ABRs) may be worth consideration due to their measurement properties (noninvasiveness; reliability) and conceptual features (well-characterized neural generators), but participant characteristics and assessment protocols vary considerably across studies. Our goal is to perform a meta-analysis of the association between ABRs and ASD. Following an electronic database search (PubMed, Medline, PsycInfo, PsycArticles), we included papers that were written in English, included ASD and typically-developing (TD) groups, and reported the information needed to calculate standardized mean differences (Hedges's g) for at least one ABR latency component (I, III, V, I-III, III-V, I-V). We weighted and averaged effect sizes across conditions and subsets of participants to yield one estimate per component per study. We then performed random-effects regressions to generate component-specific estimates. ASD was associated with longer ABR latencies for Waves III (g = 0.5, 95% CI 0.1, 0.9), V (g = 0.7, 95% CI 0.3, 1.1), I-III (g = 0.7, 95% CI 0.2, 1.2), and I-V (g = 0.6, 95% CI 0.2, 1.0). All components showed significant heterogeneity. Associations were strongest among participants ≤8 years of age and those without middle ear abnormalities or elevated auditory thresholds. In sum, associations between ABRs and ASD are medium-to-large in size, but exhibit heterogeneity. Identifying sources of heterogeneity is challenging, however, due to power limitations and co-occurrence of sample/design characteristics across studies. Research addressing the above limitations is crucial to determining the etiologic and/or prognostic value of ABRs for ASD. Autism Res 2018. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. Auditory brainstem responses (ABR) may be associated with ASD, but

  4. Test-retest reliability of speech-evoked auditory brainstem response in healthy children at a low sensation level.

    Science.gov (United States)

    Zakaria, Mohd Normani; Jalaei, Bahram

    2017-11-01

    Auditory brainstem responses evoked by complex stimuli such as speech syllables have been studied in normal subjects and subjects with compromised auditory functions. The stability of speech-evoked auditory brainstem response (speech-ABR) when tested over time has been reported but the literature is limited. The present study was carried out to determine the test-retest reliability of speech-ABR in healthy children at a low sensation level. Seventeen healthy children (6 boys, 11 girls) aged from 5 to 9 years (mean = 6.8 ± 3.3 years) were tested in two sessions separated by a 3-month period. The stimulus used was a 40-ms syllable /da/ presented at 30 dB sensation level. As revealed by pair t-test and intra-class correlation (ICC) analyses, peak latencies, peak amplitudes and composite onset measures of speech-ABR were found to be highly replicable. Compared to other parameters, higher ICC values were noted for peak latencies of speech-ABR. The present study was the first to report the test-retest reliability of speech-ABR recorded at low stimulation levels in healthy children. Due to its good stability, it can be used as an objective indicator for assessing the effectiveness of auditory rehabilitation in hearing-impaired children in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The Effects of Increasing the Stimulus Rate on Auditory Brainstem Response Waves Latency in Old Population with Normal Hearing

    Directory of Open Access Journals (Sweden)

    Massoumeh Roozbahani

    2006-12-01

    Full Text Available Background and Aim: The auditory system changes by increasing age in both central and peripheral parts. The purpose of this study was to investigate the effect of the increasing the stimulus rate on auditory brainstem response (ABR waves latency in old population with normal hearing. Materials and Methods: In this cross-sectional study click ABR test performed on 20 young normal-hearing subjects with mean age of 20.8 years old and 10 old normal-hearing subjects with mean age of 66.4 years old. ABR results with different stimulus rates were compared between two groups. Results: ABR peak latencies and interpeak intervals were prolonged with increasing the click repetition rate. Peak latencies were slightly prolonged in older adults and the I-V interval did not differ with age but prolongation of III-V interval were significantly differs in older population compared to young adults. Conclusion: Using high click rates may sensitize the ABR to the identification of lesions of auditory nerve or brainstem, but before that, we need to know the normal range of different age groups, so that we can decide about probability of a retrocochlear lesion.

  6. Methylmercury Exposure Reduces the Auditory Brainstem Response of Zebra Finches (Taeniopygia guttata ).

    Science.gov (United States)

    Wolf, Sarah E; Swaddle, John P; Cristol, Daniel A; Buchser, William J

    2017-08-01

    Mercury contamination from mining and fossil fuel combustion causes damage to humans and animals worldwide. Mercury exposure has been implicated in mammalian hearing impairment, but its effect on avian hearing is unknown. In this study, we examined whether lifetime dietary mercury exposure affected hearing in domestic zebra finches (Taeniopygia guttata) by studying their auditory brainstem responses (ABRs). Zebra finches exposed to mercury exhibited elevated hearing thresholds, decreased amplitudes, and longer latencies in the ABR, the first evidence of mercury-induced hearing impairment in birds. Birds are a more appropriate model for the human auditory spectrum than most mammals because of similarities in frequency discrimination, vocal learning, and communication behavior. When mercury is considered in combination with other anthropogenic stressors such as noise pollution and habitat alteration, the hearing impairments we document here could substantially degrade avian auditory communication in wild birds.

  7. Development of a Chirp Stimulus PC-Based Auditory Brainstem Response Audiometer

    Directory of Open Access Journals (Sweden)

    Ali AL-Afsaa

    2004-05-01

    Full Text Available Hearing losses during infancy and childhood have many negative future effects and impacts on the child life and productivity. The earlier detection of hearing losses, the earlier medical intervention and then the greater benefit of remediation will be. During this research a PC-based audiometer is designed and, currently, the audiometer prototype is in its final development steps. It is based on the auditory brainstem response (ABR method. Chirp stimuli instead of traditional click stimuli will be used to invoke the ABR signal. The stimulus is designed to synchronize the hair cells movement when it spreads out over the cochlea. In addition to the available hardware utilization (PC and PCI board, the efforts confined to design and implement a hardware prototype and to develop a software package that enables the system to behave as ABR audiometer. By using such a method and chirp stimulus, it is expected to be able to detect hearing impairment (sensorineural in the first few days of the life and conduct hearing test at low frequency of stimulus. Currently, the intended chirp stimulus has been successfully generated and the implemented module is able to amplify a signal (on the order of ABR signal to a recordable level. Moreover, a NI-DAQ data acquisition board has been chosen to implement the PC-prototype interface.

  8. Abnormal auditory forward masking pattern in the brainstem response of individuals with Asperger syndrome

    Science.gov (United States)

    Källstrand, Johan; Olsson, Olle; Nehlstedt, Sara Fristedt; Sköld, Mia Ling; Nielzén, Sören

    2010-01-01

    Abnormal auditory information processing has been reported in individuals with autism spectrum disorders (ASD). In the present study auditory processing was investigated by recording auditory brainstem responses (ABRs) elicited by forward masking in adults diagnosed with Asperger syndrome (AS). Sixteen AS subjects were included in the forward masking experiment and compared to three control groups consisting of healthy individuals (n = 16), schizophrenic patients (n = 16) and attention deficit hyperactivity disorder patients (n = 16), respectively, of matching age and gender. The results showed that the AS subjects exhibited abnormally low activity in the early part of their ABRs that distinctly separated them from the three control groups. Specifically, wave III amplitudes were significantly lower in the AS group than for all the control groups in the forward masking condition (P < 0.005), which was not the case in the baseline condition. Thus, electrophysiological measurements of ABRs to complex sound stimuli (eg, forward masking) may lead to a better understanding of the underlying neurophysiology of AS. Future studies may further point to specific ABR characteristics in AS individuals that separate them from individuals diagnosed with other neurodevelopmental diseases. PMID:20628629

  9. Effect of Sound Conditioning on Click Auditory Brainstem Response Threshold Shifts in Guinea Pigs

    Directory of Open Access Journals (Sweden)

    Masoud Motalebi Kashani

    2012-10-01

    Full Text Available Background and Aim: Sound conditioning is exposure to a non-traumatic, moderate level of sound which increases inner ear resistance against further severe noise. In this study, we aimed to survey the effect of sound conditioning on auditory brainstem response (ABR threshold shifts using click stimulus, and the effect of the frequency of conditioning on hearing protection.Methods: Fifteen guinea pigs were randomly divided into 3 groups. Two conditioned groups were exposed to 1 kHz, and 4 kHz octave band noise at 85 dB SPL, 6 hours per day for 5 days, respectively.On the sixth day, the animals were exposed to 4 kHz octave band noise at 105 dB SPL, for 4 hours.The control group was exposed to intense noise, 4 kHz at 105 Db SPL for 4 hours (withoutconditioning. After exposure, ABR thresholds using click were recorded an hour, and 7 days after noise exposure.Results: The results of the ABR with click stimulus showed less thresold shifts in conditioned groups than control (p≤0.001. Comparison of the results of conditioned groups, showed less threshold shift by 4 kHz conditioning, however, this difference was not statistically significant (p>0.05.Conclusion: Electrophysiological data of our study showed that sound conditioning has a protective effect against subsequent intensive noise exposure, and the frequency of conditioning does not havesignificant effect on ABR threshold shifts when using click stimulus.

  10. Efficiency of Melatonin as Compared to Pentobarbital for Audiometry Brainstem Response in Children With Associated Disorders.

    Science.gov (United States)

    Guerlain, Joanne; Paul, Antoine; Rouillon, Isabelle; Parodi, Marine; Garabedian, Erea Noel; Loundon, Natalie

    2016-09-01

    Outpatient pediatric audiometry brainstem response (ABR) uses various techniques (no drug, hydroxyzine, pentobarbital, melatonin). The aim of this study was to evaluate the efficiency of melatonin as compared to pentobarbital in children with associated disorders. This was a retrospective study that took place in a tertiary care center. Eighty-three children (34 girls and 49 boys) had performed ABR under pentobarbital (GPent) or melatonin (GMel) between 2013 and 2014 and were included. All children had associated neurological or behavioral disorders or had failed a previous ABR using another technique. Success rate, defined as completed binaural investigation, delay, and duration of sleep (minutes), as well as side effects, were compared between GPent and GMel. There were 56 patients in GMel and 27 in GPent, with a mean age at test of 3 years and 10 months (1-13 years) and 4 years and 1 month (1-14.5 years), respectively. Success rate was 76.8% and 88.8%, respectively (p > .05), sleep duration was 23 and 153 min (p pentobarbital. Melatonin seems to be an efficient alternative to pentobarbital for pediatric ABR.

  11. Auditory brainstem responses for click and CE-chirp stimuli in individuals with and without occupational noise exposure

    Directory of Open Access Journals (Sweden)

    Zeena Venkatacheluvaiah Pushpalatha

    2016-01-01

    Full Text Available Introduction: Encoding of CE-chirp and click stimuli in auditory system was studied using auditory brainstem responses (ABRs among individuals with and without noise exposure. Materials and Methods: The study consisted of two groups. Group 1 (experimental group consisted of 20 (40 ears individuals exposed to occupational noise with hearing thresholds within 25 dB HL. They were further divided into three subgroups based on duration of noise exposure (0–5 years of exposure-T1, 5–10 years of exposure-T2, and >10 years of exposure-T3. Group 2 (control group consisted of 20 individuals (40 ears. Absolute latency and amplitude of waves I, III, and V were compared between the two groups for both click and CE-chirp stimuli. T1, T2, and T3 groups were compared for the same parameters to see the effect of noise exposure duration on CE-chirp and click ABR. Result: In Click ABR, while both the parameters for wave III were significantly poorer for the experimental group, wave V showed a significant decline in terms of amplitude only. There was no significant difference obtained for any of the parameters for wave I. In CE-Chirp ABR, the latencies for all three waves were significantly prolonged in the experimental group. However, there was a significant decrease in terms of amplitude in only wave V for the same group. Discussion: Compared to click evoked ABR, CE-Chirp ABR was found to be more sensitive in comparison of latency parameters in individuals with occupational noise exposure. Monitoring of early pathological changes at the brainstem level can be studied effectively by using CE-Chirp stimulus in comparison to click stimulus. Conclusion: This study indicates that ABR’s obtained with CE-chirp stimuli serves as an effective tool to identify the early pathological changes due to occupational noise exposure when compared to click evoked ABR.

  12. Investigation of Auditory Brain Stem Responses (ABRs In Children with Down Syndrome

    Directory of Open Access Journals (Sweden)

    Mohsen Monadi

    2013-04-01

    Full Text Available Objective: The aim of this study was comparing ABR in normal and down children. Materials & Methods: This study was performed between 1388 to 1391 at Akhavan rehabilitation center of University of Social Welfare and Rehabilitation Sciences Tehran and Babol Amir Kola hospital. Forty five 3-6 year-old boy with Down’s syndrome and forty five normal children were selected from available population. After case history, otoscopy and basic hearing tests, ABR test was performed. In ABR absolute latencies, interpeak latencies and amplitude ratio of V/I were analyzed. For analyzing data, parametric independent t test was selected. Results: Latencies and inter-peak latencies of I-III, I-V (P-value<0.001, III-V (P-value=0.01 and V/I amplitude ratio (P-value<0.001 were shorter than normal. Children with Down syndrome had significantly higher threshold than normal children (P-value<0.001. Conclusion: Peripheral auditory system development is delayed and brainstem function in children with Down’s syndrome is abnormal. Early diagnosis of hearing impairments and intervention in these children is very important because it affects communication skills.

  13. Brainstem auditory responses to resolved and unresolved harmonics of a synthetic vowel in quiet and noise.

    Science.gov (United States)

    Laroche, Marilyn; Dajani, Hilmi R; Prévost, François; Marcoux, André M

    2013-01-01

    This study investigated speech auditory brainstem responses (speech ABR) with variants of a synthetic vowel in quiet and in background noise. Its objectives were to study the noise robustness of the brainstem response at the fundamental frequency F0 and at the first formant F1, evaluate how the resolved/unresolved harmonics regions in speech contribute to the response at F0, and investigate the origin of the response at F0 to resolved and unresolved harmonics in speech. In total, 18 normal-hearing subjects (11 women, aged 18-33 years) participated in this study. Speech ABRs were recorded using variants of a 300 msec formant-synthesized /a/ vowel in quiet and in white noise. The first experiment employed three variants containing the first three formants F1 to F3, F1 only, and F2 and F3 only with relative formant levels following those reported in the literature. The second experiment employed three variants containing F1 only, F2 only, and F3 only, with the formants equalized to the same level and the signal-to-noise ratio (SNR) maintained at -5 dB. Overall response latency was estimated, and the amplitude and local SNR of the envelope following response at F0 and of the frequency following response at F1 were compared for the different stimulus variants in quiet and in noise. The response at F0 was more robust to noise than that at F1. There were no statistically significant differences in the response at F0 caused by the three stimulus variants in both experiments in quiet. However, the response at F0 with the variant dominated by resolved harmonics was more robust to noise than the response at F0 with the stimulus variants dominated by unresolved harmonics. The latencies of the responses in all cases were very similar in quiet, but the responses at F0 due to resolved and unresolved harmonics combined nonlinearly when both were present in the stimulus. Speech ABR has been suggested as a marker of central auditory processing. The results of this study support

  14. A comparison of auditory brainstem responses across diving bird species

    Science.gov (United States)

    Crowell, Sara E.; Berlin, Alicia; Carr, Catherine E.; Olsen, Glenn H.; Therrien, Ronald E.; Yannuzzi, Sally E.; Ketten, Darlene R.

    2015-01-01

    There is little biological data available for diving birds because many live in hard-to-study, remote habitats. Only one species of diving bird, the black-footed penguin (Spheniscus demersus), has been studied in respect to auditory capabilities (Wever et al., Proc Natl Acad Sci USA 63:676–680, 1969). We, therefore, measured in-air auditory threshold in ten species of diving birds, using the auditory brainstem response (ABR). The average audiogram obtained for each species followed the U-shape typical of birds and many other animals. All species tested shared a common region of the greatest sensitivity, from 1000 to 3000 Hz, although audiograms differed significantly across species. Thresholds of all duck species tested were more similar to each other than to the two non-duck species tested. The red-throated loon (Gavia stellata) and northern gannet (Morus bassanus) exhibited the highest thresholds while the lowest thresholds belonged to the duck species, specifically the lesser scaup (Aythya affinis) and ruddy duck (Oxyura jamaicensis). Vocalization parameters were also measured for each species, and showed that with the exception of the common eider (Somateria mollisima), the peak frequency, i.e., frequency at the greatest intensity, of all species' vocalizations measured here fell between 1000 and 3000 Hz, matching the bandwidth of the most sensitive hearing range.

  15. Auditory brainstem, middle and late latency responses to short gaps in noise at different presentation rates.

    Science.gov (United States)

    Alhussaini, Khalid; Bohorquez, Jorge; Delgado, Rafael E; Ozdamar, Ozcan

    2018-01-29

    The effects of rate on auditory-evoked potentials (AEP) to short noise gaps (12 ms) recorded at high sampling rates using wide-band filters were investigated. Auditory brainstem (ABR), middle latency (MLR), late latency (LLR) and steady-state (ASSR) responses were simultaneously recorded in adult subjects at four gap rates (0.5, 1, 5 and 40 Hz). Major components (V, Na, Pa, Nb, Pb, N1 and P2) were identified at each rate and analysed for latency/amplitude characteristics. Gap responses at 40 Hz were recovered from Quasi-ASSRs (QASSR) using the CLAD deconvolution method. Fourteen right ears of young normal hearing subjects were tested. All major components were present in all subjects at 1 Hz. P1 (P50) appeared as a low-pass filtered component of Pa and Pb waves. At higher rates, N1 and P2 disappeared completely while major ABR-MLR components were identified. Peak latencies were mostly determined by noise onsets slightly delayed by offset responses. Major AEP components can be recorded to short gaps at 1 Hz using high sampling rates and wide-band filters. At higher rates, only ABR and MLRs can be recorded. Such simultaneous recordings may provide a complete assessment of temporal resolution and processing at different levels of auditory pathways.

  16. Maturation of auditory brainstem responses in young children with congenital monaural atresia.

    Science.gov (United States)

    Stuermer, Konrad Johannes; Foerst, Astrid; Sandmann, Pascale; Fuerstenberg, Dirk; Lang-Roth, Ruth; Walger, Martin

    2017-04-01

    To date, the impact of conductive hearing loss on the auditory pathway at brainstem level has only been investigated in animal studies, which showed a species-specific delay of maturation. In this study, the functional maturation of auditory brainstem response (ABR) parameters in humans with unilateral atresia of the external auditory canal was investigated. 42 newborns and toddlers ranging in age from 13 days to 11 months were included. The click-evoked ABR interpeak latencies (IPL) of the atretic ears and the contralateral ears with normal hearing were evaluated. The children had no comorbidities and had never been fitted with any kind of hearing aid. The absolute latencies (AL) and IPL of a matched control group were compared to the contralateral normally hearing ears of the children with unilateral atresia. The mean air-bone gap in the ears with atresia was 44 dB HL. Despite this partial acoustic deprivation, no significant difference between the IPLs of normal ears and ears with atresia could be detected. Both for AL and IPL, the differences between the normal ears and the control group were all within 1 standard deviation to the mean. The data showed that the monaural acoustic deprivation by a block of sound conduction does not produce any delay of functional maturation at brainstem level in this group of patients. With regard to the AL and IPL on brainstem level, no differences between the normal ears of children with unilateral atresia and children with bilateral normal hearing could be detected. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Comparison of Auditory Brainstem Response in Noise Induced Tinnitus and Non-Tinnitus Control Subjects

    Directory of Open Access Journals (Sweden)

    Ghassem Mohammadkhani

    2009-12-01

    Full Text Available Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR were compared in noise induced tinnitus and non-tinnitus control subjects.Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.Results: Mean interpeak latencies of III-V (p= 0.022, I-V (p=0.033 in ipsilatral electrode array and mean absolute latencies of IV (p=0.015 and V (p=0.048 in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group. Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

  18. [Comparative study between auditory steady-state responses, auditory brain-stem responses and liminar tonal audiometry].

    Science.gov (United States)

    Martínez Fernández, Asunción; Alañón Fernández, Miguel Angel; Ayala Martínez, Luis Félix; Alvarez Alvarez, Ana Belén; Miranda León, María Teresa; Sainz Quevedo, Manuel

    2007-01-01

    Auditory steady-state responses (ASSR) using frequencies of modulation between 70-110 Hz are a new auditive exploration technique. The aim of the study was to evaluate the contribution of the ASSR to diagnostic of the audition. Different aportations of auditory steady-states responses (ASSR) and auditory brain-stem responses (ABR) to diagnostic of threshold of audition were studied Differences between these thresholds and thresholds obtained by liminar tonal audiometry (LTA) were studied too. Correlations between thresholds obtained by ASSR and LTA were studied. ASSR detected rest of audition that transients ABR did not detect. Differences about -13.750 dB HL (-5.209 to -22.291) and -13.250 dB HL (-7.337 to -19.163) were found between registered values for carriers of 500 and 1000 Hz and the thresholds by LTA for these carriers. Differences about 1.625 dB HL (-6.967 to 10.217) and -2.875 dB HL (-7.446 to 1.696) were found between estimations for the carries of 500 and 1000 Hz and thresholds by TLA. Statistically very significant (P=.01) coefficients of correlation were found between registered and estimated thresholds by ASSR for carrier of 500 and 1000 Hz and threshold by TLA for these frequencies. Auditory steady-state responses (ASSR) using frequencies of modulation between 70-110 Hz are a new auditive technique of exploration. This stimulus is more frequency-specific than clicks for auditory brain-stem responses (ABR). Response is not modificated by steady of consciousness. The technique is doublely objective. Thresholds obtained by ASSR permits to estimation of the audition threshold.

  19. Usefulness of Electrical Auditory Brainstem Responses to Assess the Functionality of the Cochlear Nerve Using an Intracochlear Test Electrode.

    Science.gov (United States)

    Lassaletta, Luis; Polak, Marek; Huesers, Jan; Díaz-Gómez, Miguel; Calvino, Miryam; Varela-Nieto, Isabel; Gavilán, Javier

    2017-12-01

    To use an intracochlear test electrode to assess the integrity and the functionality of the auditory nerve in cochlear implant (CI) recipients and to compare electrical auditory brainstem responses (eABR) via the test electrode with the eABR responses with the CI. Otolaryngology department, tertiary referral hospital. Ten subjects (age at implantation 55 yr, range, 19-72) were subsequently implanted with a MED-EL CONCERTO CI on the side without any useful residual hearing. Following identification of the round window (RW), the test electrode was inserted in the cochlea previous to cochlear implantation. To assess the quality of an eABR waveform, scoring criteria from Walton et al. (2008) were chosen. The waveforms in each session were classified by detecting waves III and V by the algorithm and visual assessment of the waveform. Speech performance was evaluated with monosyllables, disyllables, and sentence recognition tests. It was possible to evoke electrical stimulation responses along with both the test electrode and the CI in all subjects. No significant differences in latencies or amplitudes after stimulation were found between the test electrode and the CI. All subjects obtained useful hearing with their CI and use their implants daily. The intracochlear test electrode may be suitable to test the integrity of the auditory nerve by recording eABR signals. This allows for further research on the status of the auditory nerve after tumor removal and correlation with auditory performance.

  20. Long-term evolution of brainstem electrical evoked responses to sound after restricted ablation of the auditory cortex.

    Directory of Open Access Journals (Sweden)

    Verónica Lamas

    Full Text Available INTRODUCTION: This study aimed to assess the top-down control of sound processing in the auditory brainstem of rats. Short latency evoked responses were analyzed after unilateral or bilateral ablation of auditory cortex. This experimental paradigm was also used towards analyzing the long-term evolution of post-lesion plasticity in the auditory system and its ability to self-repair. METHOD: Auditory cortex lesions were performed in rats by stereotactically guided fine-needle aspiration of the cerebrocortical surface. Auditory Brainstem Responses (ABR were recorded at post-surgery day (PSD 1, 7, 15 and 30. Recordings were performed under closed-field conditions, using click trains at different sound intensity levels, followed by statistical analysis of threshold values and ABR amplitude and latency variables. Subsequently, brains were sectioned and immunostained for GAD and parvalbumin to assess the location and extent of lesions accurately. RESULTS: Alterations in ABR variables depended on the type of lesion and post-surgery time of ABR recordings. Accordingly, bilateral ablations caused a statistically significant increase in thresholds at PSD1 and 7 and a decrease in waves amplitudes at PSD1 that recover at PSD7. No effects on latency were noted at PSD1 and 7, whilst recordings at PSD15 and 30 showed statistically significant decreases in latency. Conversely, unilateral ablations had no effect on auditory thresholds or latencies, while wave amplitudes only decreased at PSD1 strictly in the ipsilateral ear. CONCLUSION: Post-lesion plasticity in the auditory system acts in two time periods: short-term period of decreased sound sensitivity (until PSD7, most likely resulting from axonal degeneration; and a long-term period (up to PSD7, with changes in latency responses and recovery of thresholds and amplitudes values. The cerebral cortex may have a net positive gain on the auditory pathway response to sound.

  1. Effects of noise exposure on neonatal auditory brainstem response thresholds in pregnant guinea pigs at different gestational periods.

    Science.gov (United States)

    Morimoto, Chihiro; Nario, Kazuhiko; Nishimura, Tadashi; Shimokura, Ryota; Hosoi, Hiroshi; Kitahara, Tadashi

    2017-01-01

    Noise exposure during pregnancy has been reported to cause fetal hearing impairment. However, little is known about the effects of noise exposure during various gestational stages on postnatal hearing. In the present study, we investigated the effects of noise exposure on auditory brainstem response (ABR) at the early, mid-, and late gestational periods in newborn guinea pigs. Pregnant guinea pigs were exposed to 4-kHz pure tone at a 120-dB sound pressure level for 4 h. We divided the animals into four groups as follows: the control, early gestational exposure, mid-gestational exposure, and late gestational exposure groups. ABR thresholds and latencies in newborns were recorded using 1-, 2-, and 4-kHz tone burst on postnatal days 1, 7, 14, and 28. Changes in ABR thresholds and latencies were measured between the 4 × 4 and 4 × 3 factorial groups mentioned above (gestational periods × postnatal days, gestational periods × frequencies). The thresholds were low in the order of control group guinea pigs. This is the first study to show that noise exposure during the early, mid-, and late gestational periods significantly elevated ABR thresholds in neonatal guinea pigs. © 2016 Japan Society of Obstetrics and Gynecology.

  2. Air and Bone Conduction Frequency-specific Auditory Brainstem Response in Children with Agenesis of the External Auditory Canal.

    Science.gov (United States)

    Sleifer, Pricila; Didoné, Dayane Domeneghini; Keppeler, Ísis Bicca; Bueno, Claudine Devicari; Riesgo, Rudimar Dos Santos

    2017-10-01

    Introduction  The tone-evoked auditory brainstem responses (tone-ABR) enable the differential diagnosis in the evaluation of children until 12 months of age, including those with external and/or middle ear malformations. The use of auditory stimuli with frequency specificity by air and bone conduction allows characterization of hearing profile. Objective  The objective of our study was to compare the results obtained in tone-ABR by air and bone conduction in children until 12 months, with agenesis of the external auditory canal. Method  The study was cross-sectional, observational, individual, and contemporary. We conducted the research with tone-ABR by air and bone conduction in the frequencies of 500 Hz and 2000 Hz in 32 children, 23 boys, from one to 12 months old, with agenesis of the external auditory canal. Results  The tone-ABR thresholds were significantly elevated for air conduction in the frequencies of 500 Hz and 2000 Hz, while the thresholds of bone conduction had normal values in both ears. We found no statistically significant difference between genders and ears for most of the comparisons. Conclusion  The thresholds obtained by bone conduction did not alter the thresholds in children with conductive hearing loss. However, the conductive hearing loss alter all thresholds by air conduction. The tone-ABR by bone conduction is an important tool for assessing cochlear integrity in children with agenesis of the external auditory canal under 12 months.

  3. The brain stem function in patients with brain bladder; Clinical evaluation using dynamic CT scan and auditory brainstem response

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Toshihiro (Yokohama City Univ. (Japan). Faculty of Medicine)

    1990-11-01

    A syndrome of detrusor-sphincter dyssynergia (DSD) is occasionally found in patients with brain bladder. To evaluate the brain stem function in cases of brain bladder, urodynamic study, dynamic CT scan of the brain stem (DCT) and auditory brainstem response (ABR) were performed. The region of interest of DCT aimed at the posterolateral portion of the pons. The results were analysed in contrast with the presense of DSD in urodynamic study. DCT studies were performed in 13 cases with various brain diseases and 5 control cases without neurological diseases. Abnormal patterns of the time-density curve consisted of low peak value, prolongation of filling time and low rapid washout ratio (low clearance ratio) of the contrast medium. Four of 6 cases with DSD showed at least one of the abnormal patterns of the time-density curve bilaterally. In 7 cases without DSD none showed bilateral abnormality of the curve and in 2 of 7 cases only unilateral abnormality was found. ABR was performed in 8 patients with brain diseases. The interpeak latency of the wave I-V (I-V IPL) was considered to be prolonged in 2 cases with DSD compared to that of 4 without DSD. In 2 cases with DSD who had normal DCT findings, measurement of the I-V IPL was impossible due to abnormal pattern of the ABR wave. Above mentioned results suggests the presence of functional disturbance at the posterolateral portion of the pons in cases of brain bladder with DSD. (author).

  4. Prenatal exposure to multiple pesticides is associated with auditory brainstem response at 9months in a cohort study of Chinese infants.

    Science.gov (United States)

    Sturza, Julie; Silver, Monica K; Xu, Lin; Li, Mingyan; Mai, Xiaoqin; Xia, Yankai; Shao, Jie; Lozoff, Betsy; Meeker, John

    2016-01-01

    Pesticides are associated with poorer neurodevelopmental outcomes, but little is known about the effects on sensory functioning. Auditory brainstem response (ABR) and pesticide data were available for 27 healthy, full-term 9-month-old infants participating in a larger study of early iron deficiency and neurodevelopment. Cord blood was analyzed by gas chromatography-mass spectrometry for levels of 20 common pesticides. The ABR forward-masking condition consisted of a click stimulus (masker) delivered via ear canal transducers followed by an identical stimulus delayed by 8, 16, or 64 milliseconds (ms). ABR peak latencies were evaluated as a function of masker-stimulus time interval. Shorter wave latencies reflect faster neural conduction, more mature auditory pathways, and greater degree of myelination. Linear regression models were used to evaluate associations between total number of pesticides detected and ABR outcomes. We considered an additive or synergistic effect of poor iron status by stratifying our analysis by newborn ferritin (based on median split). Infants in the sample were highly exposed to pesticides; a mean of 4.1 pesticides were detected (range 0-9). ABR Wave V latency and central conduction time (CCT) were associated with the number of pesticides detected in cord blood for the 64ms and non-masker conditions. A similar pattern seen for CCT from the 8ms and 16ms conditions, although statistical significance was not reached. Increased pesticide exposure was associated with longer latency. The relation between number of pesticides detected in cord blood and CCT depended on the infant's cord blood ferritin level. Specifically, the relation was present in the lower cord blood ferritin group but not the higher cord blood ferritin group. ABR processing was slower in infants with greater prenatal pesticide exposure, indicating impaired neuromaturation. Infants with lower cord blood ferritin appeared to be more sensitive to the effects of prenatal pesticide

  5. Type-2 diabetes mellitus and auditory brainstem response.

    Science.gov (United States)

    Siddiqi, Sheelu S; Gupta, Rahul; Aslam, Mohd; Hasan, Syed Abrar; Khan, Shakeel Ahmad

    2013-11-01

    Diabetes mellitus (DM) causes pathophysiological changes at multiple organ system. With evoked potential techniques, the brain stem auditory response represents a simple procedure to detect both acoustic nerve and central nervous system pathway damage. The objective was to find the evidence of central neuropathy in diabetes patients by analyzing brainstem audiometry electric response obtained by auditory evoked potentials, quantify the characteristic of auditory brain response in long standing diabetes and to study the utility of auditory evoked potential in detecting the type, site, and nature of lesions. A total of 25 Type-2 DM [13 (52%) males and 12 (48%) females] with duration of diabetes over 5 years and aged over 30 years. The brainstem evoked response audiometry (BERA) was performed by universal smart box manual version 2.0 at 70, 80, and 90 dB. The wave latency pattern and interpeak latencies were estimated. This was compared with 25 healthy controls (17 [68%] males and 8 [32%] females). In Type-2 DM, BERA study revealed that wave-III representing superior olivary complex at 80 dB had wave latency of (3.99 ± 0.24) ms P diabetic neuropathy, of which 12 (92%) showed abnormal BERA. In nonneuropathic [12 (48%)] only 6 (50%) showed abnormal BERA. Delay in absolute latencies and interpeak latencies by BERA demonstrates defect at level of brainstem and midbrain in long standing Type-2 diabetes subjects, which is more pronounced in those with neuropathy.

  6. Brainstem evoked potentials in infantile spasms; Comparison with MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Masahito; Hashimoto, Toshiaki; Murakawa, Kazuyoshi; Tayama, Masanobu; Kuroda, Yasuhiro (Tokushima Univ. (Japan). School of Medicine)

    1992-08-01

    In ten patients with infantile spasms, brainstem evoked potentials and MRI examinations were performed to evaluate the brainstem involvement. The result of short latency somatosensory evoked potentials (SSEP) following the right median nerve stimulation revealed abnormal findings including the absence or low amplitudes of the waves below wave P3 and delayed central conduction time in 7 of the ten patients. The result of auditory brainstem responses (ABR) revealed abnormal findings including low amplitudes of wave V, prolonged interpeak latency of waves I-V and absence of the waves below wave IV in 5 of the ten patients. The result of the MRI examinations revealed various degrees of the brainstem atrophy in 6 of the ten patients, all of whom showed abnormal brainstem evoked potentials. The result of this study demonstrates that patients with infantile spasms are frequently associated with brainstem dysfunction and raises the possibility that brainstem atrophy might be a cause of infantile spasms. (author).

  7. Otoacoustic emissions and auditory brainstem responses in patients with sudden sensorineural hearing loss. Do otoacoustic emissions have prognostic value?

    Directory of Open Access Journals (Sweden)

    Manoochehr Amiridavan

    2006-11-01

    Full Text Available BACKGROUND: Sudden sensorineural hearing loss (SSNHL is a perplexing condition for patients and there are many controversies about its etiology, audiologic characteristics, prognostic factors, and treatment. METHODS: In this prospective study, we performed some audiologic tests, including PTA, IA, ABR, and OAE (TEOAE before beginning treatment of 53 patients with SSNHL. We assigned the patients randomly to two treatment groups: oral steroids + acyclovir vs. intravenous urographin. Twenty-eight patients underwent Magnetic Resonance Imaging (MRI of the Brain. RESULTS: Of 53 patients (22 female and 31 male, 22 (41.5% had negative or no signal to noise ratio and overall correlation in TEOAE. Twenty-six patients (49% had positive overall correlations less than 50%, and 5 patients (4.4% had overall correlations >50%. Fifteen patients (28. 3% responded completely or well, 20 (37.7% responded partially, and 18 (33.9% had poor or no response to the treatment. The mean values for overall correlation in 3 subgroups of patients (no response, partial response, and complete response were – 3. 5% (+ 1/16%, +11% (+ 1/99%, and +36.6% (+3/07%, respectively (P = 0.01. Twenty out of 52 patients had no reproducible wave in ABR (38.5%, and waves I, III, and V were absent in 40 (77%, 31 (59.6% and 21 (40% patients, respectively. There were some limitations (false positive and false negative results in ABR use in our cases, but it may be useful in detecting site of lesion in SSNHL. Overall, according to the results of OAE, ABR, and brain MRI of these patients, 3 were affected by acoustic neurinomas, at least 1 had auditory neuropathy, and the site of lesion was cochlear in 6, and cochlear + retrocochlear in 13 patients. CONCLUSIONS: ABR has limitations for use in SSNHL and seems not to obviate the need for brain MRI, but may help in determining the site of lesions such as ischemia or neuropathy. Overall correlation (and S/N ratio in TEOAE is a valuable

  8. Relations between perceptual measures of temporal processing, auditory-evoked brainstem responses and speech intelligibility in noise

    DEFF Research Database (Denmark)

    Papakonstantinou, Alexandra; Strelcyk, Olaf; Dau, Torsten

    2011-01-01

    This study investigates behavioural and objective measures of temporal auditory processing and their relation to the ability to understand speech in noise. The experiments were carried out on a homogeneous group of seven hearing-impaired listeners with normal sensitivity at low frequencies (up to 1...... kHz) and steeply sloping hearing losses above 1 kHz. For comparison, data were also collected for five normalhearing listeners. Temporal processing was addressed at low frequencies by means of psychoacoustical frequency discrimination, binaural masked detection and amplitude modulation (AM......) detection. In addition, auditory brainstem responses (ABRs) to clicks and broadband rising chirps were recorded. Furthermore, speech reception thresholds (SRTs) were determined for Danish sentences in speechshaped noise. The main findings were: (1) SRTs were neither correlated with hearing sensitivity...

  9. Auditory brainstem responses of CBA/J mice with neonatal conductive hearing losses and treatment with GM1 ganglioside.

    Science.gov (United States)

    Money, M K; Pippin, G W; Weaver, K E; Kirsch, J P; Webster, D B

    1995-07-01

    Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.

  10. Auditory Brainstem Responses to Bone-Conducted Brief Tones in Young Children with Conductive or Sensorineural Hearing Loss

    Directory of Open Access Journals (Sweden)

    Jennifer L. Hatton

    2012-01-01

    Full Text Available The bone-conduction (BC tone ABR has been used clinically for over 20 years. The current study formally evaluated the test performance of the BC tone-evoked ABR in infants with hearing loss. Method. By comparing BC-ABR results to follow-up behavioural results, this study addressed two questions: (i whether the BC tone ABR was successful in differentiating children with conductive versus sensorineural hearing loss (Study A; conductive: 68 ears; SNHL: 129 ears and (ii the relationship between BC ABR and behavioural hearing loss severity (Study B: 2000 Hz: 104 ears; 500 Hz: 47 ears. Results. Results demonstrate that the “normal” BC-ABR levels accurately differentiated normal versus elevated cochlear sensitivity (accuracy: 98% for 2000 Hz; 98% for 500 Hz. A subset of infants in Study A with elevated BC-ABR (i.e., no response at normal level had additional testing at higher intensities, which allowed for categorization of the degree of cochlear impairment. Study B results indicate that the BC ABR accurately categorizes the degree of cochlear hearing loss for 2000 Hz (accuracy = 95.2%. A preliminary dBnHL-to-dBHL correction factor of “0 dB” was determined for 2000 Hz BC ABR. Conclusions. These findings further support the use of BC tone ABR for diagnostic ABR testing.

  11. Auditory Brainstem Responses to Bone-Conducted Brief Tones in Young Children with Conductive or Sensorineural Hearing Loss

    Science.gov (United States)

    Hatton, Jennifer L.; Janssen, Renée M.; Stapells, David R.

    2012-01-01

    The bone-conduction (BC) tone ABR has been used clinically for over 20 years. The current study formally evaluated the test performance of the BC tone-evoked ABR in infants with hearing loss. Method. By comparing BC-ABR results to follow-up behavioural results, this study addressed two questions: (i) whether the BC tone ABR was successful in differentiating children with conductive versus sensorineural hearing loss (Study A; conductive: 68 ears; SNHL: 129 ears) and (ii) the relationship between BC ABR and behavioural hearing loss severity (Study B: 2000 Hz: 104 ears; 500 Hz: 47 ears). Results. Results demonstrate that the “normal” BC-ABR levels accurately differentiated normal versus elevated cochlear sensitivity (accuracy: 98% for 2000 Hz; 98% for 500 Hz). A subset of infants in Study A with elevated BC-ABR (i.e., no response at normal level) had additional testing at higher intensities, which allowed for categorization of the degree of cochlear impairment. Study B results indicate that the BC ABR accurately categorizes the degree of cochlear hearing loss for 2000 Hz (accuracy = 95.2%). A preliminary dBnHL-to-dBHL correction factor of “0 dB” was determined for 2000 Hz BC ABR. Conclusions. These findings further support the use of BC tone ABR for diagnostic ABR testing. PMID:22988461

  12. Brainstem auditory evoked response characteristics in normal-hearing subjects with chronic tinnitus and in non-tinnitus group

    Directory of Open Access Journals (Sweden)

    Shadman Nemati

    2014-06-01

    Full Text Available Background and Aim: While most of the people with tinnitus have some degrees of hearing impairment, a small percent of patients admitted to ear, nose and throat clinics or hearing evaluation centers are those who complain of tinnitus despite having normal hearing thresholds. This study was performed to better understanding of the reasons of probable causes of tinnitus and to investigate possible changes in the auditory brainstem function in normal-hearing patients with chronic tinnitus.Methods: In this comparative cross-sectional, descriptive and analytic study, 52 ears (26 with and 26 without tinnitus were examined. Components of the auditory brainstem response (ABR including wave latencies and wave amplitudes were determined in the two groups and analyzed using appropriate statistical methods.Results: The mean differences between the absolute latencies of waves I, III and V was less than 0.1 ms between the two groups that was not statistically significant. Also, the interpeak latency values of waves I-III, III-V and I-V in both groups had no significant difference. Only, the V/I amplitude ratio in the tinnitus group was significantly higher (p=0.04.Conclusion: The changes observed in amplitude of waves, especially in the latter ones, can be considered as an indication of plastic changes in neuronal activity and its possible role in generation of tinnitus in normal-hearing patients.

  13. Contribution of resolved and unresolved harmonic regions to brainstem speech-evoked responses in quiet and in background noise

    Directory of Open Access Journals (Sweden)

    M. Laroche

    2011-03-01

    Full Text Available Speech auditory brainstem responses (speech ABR reflect activity that is phase-locked to the harmonics of the fundamental frequency (F0 up to at least the first formant (F1. Recent evidence suggests that responses at F0 in the presence of noise are more robust than responses at F1, and are also dissociated in some learning-impaired children. Peripheral auditory processing can be broadly divided into resolved and unresolved harmonic regions. This study investigates the contribution of these two regions to the speech ABR, and their susceptibility to noise. We recorded, in quiet and in background white noise, evoked responses in twelve normal hearing adults in response to three variants of a synthetic vowel: i Allformants, which contains all first three formants, ii F1Only, which is dominated by resolved harmonics, and iii F2&F3Only, which is dominated by unresolved harmonics. There were no statistically significant differences in the response at F0 due to the three variants of the stimulus in quiet, nor did the noise affect this response with the Allformants and F1Only variants. On the other hand, the response at F0 with the F2&F3Only variant was significantly weaker in noise than with the two other variants (p<0.001. With the response at F1, there was no difference with the Allformants and F1Only variants in quiet, but was expectedly weaker with the F2&F3Only variant (p<0.01. The addition of noise significantly weakened the response at F1 with the F1Only variant (p<0.05, but this weakening only tended towards significance with the Allformants variant (p=0.07. The results of this study indicate that resolved and unresolved harmonics are processed in different but interacting pathways that converge in the upper brainstem. The results also support earlier work on the differential susceptibility of responses at F0 and F1 to added noise.

  14. On the approximation with Chebyshev`s Q-function to ABR waveform and the estimation of its characteristics; Chebyshev q kansu ni yoru ABR hakei kinji to tokusei suitei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Ikawa, N.; Kurata, T. [Chiba University, Chiba (Japan); Kato, S. [Teikyo Heisei University, Tokyo (Japan); Aruga, M. [Tokai University, Tokai (Japan)

    1998-10-01

    It is well known that ABR (Auditory Brainstem Responses) waveforms are used when the judge of the brain death or the check of some hearing troubles and so on are needed. The physiological side of this responses is nearly made clear, but the systematic mechanism of them is not investigated sufficiently. Therefore the quantitative estimation of those systematic mechanism is not yet obtained sufficiently. In this paper, firstly the polynomial approximation results of the entire ABR waveform are shown by using the Chebyshev`s q-function. Secondarily the tendency of the latency (a parameter of ABR) is considered and compared with the experimental formula which was independently derived from the another data and analysis. Through these discussion it was shown that the indices of the quantitative analysis of characteristics of ABR parameters were given as the polynomial approximate functions of the use of the approximate method applying the Chebyshev`s q-function. 6 refs., 1 figs., 2 tabs.

  15. Type-2 diabetes mellitus and auditory brainstem response

    Directory of Open Access Journals (Sweden)

    Sheelu S Siddiqi

    2013-01-01

    Full Text Available Objective: Diabetes mellitus (DM causes pathophysiological changes at multiple organ system. With evoked potential techniques, the brain stem auditory response represents a simple procedure to detect both acoustic nerve and central nervous system pathway damage. The objective was to find the evidence of central neuropathy in diabetes patients by analyzing brainstem audiometry electric response obtained by auditory evoked potentials, quantify the characteristic of auditory brain response in long standing diabetes and to study the utility of auditory evoked potential in detecting the type, site, and nature of lesions. Design: A total of 25 Type-2 DM [13 (52% males and 12 (48% females] with duration of diabetes over 5 years and aged over 30 years. The brainstem evoked response audiometry (BERA was performed by universal smart box manual version 2.0 at 70, 80, and 90 dB. The wave latency pattern and interpeak latencies were estimated. This was compared with 25 healthy controls (17 [68%] males and 8 [32%] females. Result: In Type-2 DM, BERA study revealed that wave-III representing superior olivary complex at 80 dB had wave latency of (3.99 ± 0.24 ms P < 0.001, at 90 dB (3.92 ± 0.28 ms P < 0.001 compared with control. The latency of wave III was delayed by 0.39, 0.42, and 0.42 ms at 70, 80, and 90 dB, respectively. The absolute latency of wave V representing inferior colliculus at 70 dB (6.05 ± 0.27 ms P < 0.001, at 80 dB (5.98 ± 0.27 P < 0.001, and at 90 dB (6.02 ± 0.30 ms P < 0.002 compared with control. The latency of wave-V was delayed by 0.48, 0.47, and 0.50 ms at 70, 80, and 90 dB, respectively. Interlatencies I-III at 70 dB (2.33 ± 0.22 ms P < 0.001, at 80 dB (2.39 ± 0.26 ms P < 0.001, while at 90 dB (2.47 ± 0.25 ms P < 0.001 when compared with control. Interlatencies I-V at 70 dB (4.45 ± 0.29 ms P < 0.001 at 80 dB (4.39 ± 0.34 ms P < 0.001, and at 90 dB (4.57 ± 0.31 ms P < 0.001 compared with control. Out of 25 Type-2 DM, 13 (52

  16. Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

    Directory of Open Access Journals (Sweden)

    Renata Mota Mamede de Carvallo

    2008-09-01

    Full Text Available Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU, as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests could be applied to all babies. The “pass” result for the group of babies from the nursery was 94.7% using Transient Evoked Otoacoustic Emissions and 96% using Automatic Auditory Brainstem Response. The newborn intensive care unit group obtained 87.1% on Transient Evoked Otoacoustic Emissions and 80% on the Automatic Auditory Brainstem Response, and there was no statistical difference between the procedures when the groups were evaluated individually. However, comparing the groups, Transient Evoked Otoacoustic Emissions were presented in 94.7% of the nursery babies and in 87.1% in the group from the newborn intensive care unit. Considering the Automatic Auditory Brainstem Response, we found 96 and 87%, respectively. Cconclusions: Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response had similar “pass” and “fail” results when the procedures were applied to neonates from the regular nursery, and the combined tests were more precise to detect hearing impairment in the newborn intensive care unit babies.

  17. Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

    OpenAIRE

    Renata Mota Mamede de Carvallo; Carla Gentile Matas; Isabela de Souza Jardim

    2008-01-01

    Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU), as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem...

  18. Noise-Induced “Toughening” Effect in Wistar Rats: Enhanced Auditory Brainstem Responses Are Related to Calretinin and Nitric Oxide Synthase Upregulation

    Science.gov (United States)

    Alvarado, Juan C.; Fuentes-Santamaría, Verónica; Gabaldón-Ull, María C.; Jareño-Flores, Tania; Miller, Josef M.; Juiz, José M.

    2016-01-01

    An appropriate conditioning noise exposure may reduce a subsequent noise-induced threshold shift. Although this “toughening” effect helps to protect the auditory system from a subsequent traumatic noise exposure, the mechanisms that regulate this protective process are not fully understood yet. Accordingly, the goal of the present study was to characterize physiological processes associated with “toughening” and to determine their relationship to metabolic changes in the cochlea and cochlear nucleus (CN). Auditory brainstem responses (ABR) were evaluated in Wistar rats before and after exposures to a sound conditioning protocol consisting of a broad-band white noise of 118 dB SPL for 1 h every 72 h, four times. After the last ABR evaluation, animals were perfused and their cochleae and brains removed and processed for the activity markers calretinin (CR) and neuronal nitric oxide synthase (nNOS). Toughening was demonstrated by a progressively faster recovery of the threshold shift, as well as wave amplitudes and latencies over time. Immunostaining revealed an increase in CR and nNOS levels in the spiral ganglion, spiral ligament, and CN in noise-conditioned rats. Overall, these results suggest that the protective mechanisms of the auditory toughening effect initiate in the cochlea and extend to the central auditory system. Such phenomenon might be in part related to an interplay between CR and nitric oxide signaling pathways, and involve an increased cytosolic calcium buffering capacity induced by the noise conditioning protocol. PMID:27065815

  19. Speech-evoked auditory brainstem responses reflect familial and cognitive influences.

    Science.gov (United States)

    Hornickel, Jane; Lin, Deborah; Kraus, Nina

    2013-01-01

    Cortical function and related cognitive, language, and communication skills are genetically influenced. The auditory brainstem response to speech is linked to language skill, reading ability, cognitive skills, and speech-in-noise perception; however, the impact of shared genetic and environmental factors on the response has not been investigated. We assessed auditory brainstem responses to speech presented in quiet and background noise from (1) 23 pairs of same sex, same learning diagnosis siblings (Siblings), (2) 23 unrelated children matched on age, sex, IQ, and reading ability to one of the siblings (Reading-Matched), and (3) 22 pairs of unrelated children matched on age and sex but not on reading ability to the same sibling (Age/Sex-Matched). By quantifying response similarity as the intersubject response-to-response correlation for sibling pairs, reading-matched pairs, and age- and sex-matched pairs, we found that siblings had more similar responses than age- and sex-matched pairs and reading-matched pairs. Similarity of responses between siblings was as high as the similarity of responses collected from an individual over the course of the recording session. Responses from unrelated children matched on reading were more similar than responses from unrelated children matched only on age and sex, supporting previous data linking variations in auditory brainstem activity with variations in reading ability. These results suggest that auditory brainstem function can be influenced by siblingship and auditory-based communication skills such as reading, motivating the use of speech-evoked auditory brainstem responses for assessing risk of reading and communication impairments in family members. © 2012 Blackwell Publishing Ltd.

  20. Classification of auditory brainstem responses through symbolic pattern discovery.

    Science.gov (United States)

    Molina, Marco E; Perez, Aurora; Valente, Juan P

    2016-06-01

    Numeric time series are present in a very wide range of domains, including many branches of medicine. Data mining techniques have proved to be useful for knowledge discovery in this type of data and for supporting decision-making processes. The overall objective is to classify time series based on the discovery of frequent patterns. These patterns will be discovered in symbolic sequences obtained from the time series data by means of a temporal abstraction process. Firstly, we transform numeric time series into symbolic time sequences, where the symbols aim to represent the relevant domain concepts. These symbols can be defined using either public or expert domain knowledge. Then we apply a symbolic pattern discovery technique to the output symbolic sequences. This technique identifies the subsequences frequently found in a population group. These subsequences (patterns) are representative of population groups. Finally, we employ a classification technique based on the identified patterns in order to classify new individuals. Thanks to the inclusion of domain knowledge, the classification results can be explained using domain terminology. This makes the results easier to interpret for the domain specialist (physician). This method has been applied to brainstem auditory evoked potentials (BAEPs) time series. Preliminary experiments were carried out to analyse several aspects of the method including the best configuration of the pattern discovery technique parameters. We then applied the method to the BAEPs of 83 individuals belonging to four classes (healthy, conductive hearing loss, vestibular schwannoma-brainstem involvement and vestibular schwannoma-8th-nerve involvement). According to the results of the cross-validation, overall accuracy was 99.4%, sensitivity (recall) was 97.6% and specificity was 100% (no false positives). The proposed method effectively reduces dimensionality. Additionally, if the symbolic transformation includes the right domain knowledge

  1. Brainstem auditory evoked responses and ophthalmic findings in llamas and alpacas in eastern Canada

    OpenAIRE

    Webb, Aubrey A.; Cullen, Cheryl L.; Lamont, Leigh A.

    2006-01-01

    Seventeen llamas and 23 alpacas of various coat and iris colors were evaluated for: 1) deafness by using brainstem auditory evoked response testing; and 2) for ocular abnormalities via complete ophthalmic examination. No animals were deaf. The most common ocular abnormalities noted were iris-to-iris persistent pupillary membranes and incipient cataracts.

  2. Modeling human auditory evoked brainstem responses based on nonlinear cochlear processing

    DEFF Research Database (Denmark)

    Harte, James; Rønne, Filip Munch; Dau, Torsten

    2010-01-01

    The aim of this study was to accurately simulate auditory evoked potentials (AEPs) from various classical stimuli such as clicks and tones, often used in research and clinical diagnostics. In an approach similar to Dau (2003), a model was developed for the generation of auditory brainstem responses...

  3. Relation between derived-band auditory brainstem response latencies and behavioral frequency selectivity

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

    2009-01-01

    for some of the HI listeners. The behavioral auditory-filter bandwidths accounted for the across-listener variability in the ABR latencies: Cochlear response time decreased with increasing filter bandwidth, consistent with linear-system theory. The results link cochlear response time and frequency...... response times. For the same listeners, auditory-filter bandwidths at 2 kHz were estimated using a behavioral notched-noise masking paradigm. Generally, shorter derived-band latencies were observed for the HI than for the NH listeners. Only at low click sensation levels, prolonged latencies were obtained...

  4. Auditory Site of Lesion in Infants Suffering from Hyperbilirubinemia by Using ABR and TEOAEs

    Directory of Open Access Journals (Sweden)

    Mehdi Akbari

    2006-12-01

    Full Text Available Background and Aim: Hyperbilirubinemia is one of the most common abnormalities during the neonatal period. Approximately 60% full-term and 80% preterm neonates suffer from hyperbilirubinemia. Hearing loss is one of the most prevalent side-effects of hyperbilirubinemia. This happens when the serum concentration of indirect bilirubin increases dramatically. The main purpose of this study is to evaluate the hearing status and to diagnose the probable site of lesion in affected children. Materials and Methods : In this cross-sectional study, 33 newborn to two year old subjects suffering from hyperbilirubinemia were evaluated using auditory brainstem response (ABR and transient evoked otoacoustic emissions (TEOAE tests In the Audiology department of the Faculty of Rehabilitation Sciences Iran University of Medical Sciences sampling method was accessible. Results: 21% of the subjects had severe to profound hearing loss and 9% of subjects had mild to moderate hearing loss. In 15% of the subjects there was no response to ABR and TEOAE tests indicating cochlear and/or retrocochlear lesion. The other 15% manifest only abnormal ABR test indicating the presence of the auditory neuropathy. Conclusion: TEOAE test has its own limitations in these subjects, that is the hearing status of such patients can not be completely evaluated by using just TEOAE test. Therefore, to detect hearing loss both ABR and TEOAE tests must be performed in these subjects.

  5. Evidence of "hidden hearing loss" following noise exposures that produce robust TTS and ABR wave-I amplitude reductions.

    Science.gov (United States)

    Lobarinas, Edward; Spankovich, Christopher; Le Prell, Colleen G

    2017-06-01

    In animals, noise exposures that produce robust temporary threshold shifts (TTS) can produce immediate damage to afferent synapses and long-term degeneration of low spontaneous rate auditory nerve fibers. This synaptopathic damage has been shown to correlate with reduced auditory brainstem response (ABR) wave-I amplitudes at suprathreshold levels. The perceptual consequences of this "synaptopathy" remain unknown but have been suggested to include compromised hearing performance in competing background noise. Here, we used a modified startle inhibition paradigm to evaluate whether noise exposures that produce robust TTS and ABR wave-I reduction but not permanent threshold shift (PTS) reduced hearing-in-noise performance. Animals exposed to 109 dB SPL octave band noise showed TTS >30 dB 24-h post noise and modest but persistent ABR wave-I reduction 2 weeks post noise despite full recovery of ABR thresholds. Hearing-in-noise performance was negatively affected by the noise exposure. However, the effect was observed only at the poorest signal to noise ratio and was frequency specific. Although TTS >30 dB 24-h post noise was a predictor of functional deficits, there was no relationship between the degree of ABR wave-I reduction and degree of functional impairment. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Selective attention modulates human auditory brainstem responses: relative contributions of frequency and spatial cues.

    Directory of Open Access Journals (Sweden)

    Alexandre Lehmann

    Full Text Available Selective attention is the mechanism that allows focusing one's attention on a particular stimulus while filtering out a range of other stimuli, for instance, on a single conversation in a noisy room. Attending to one sound source rather than another changes activity in the human auditory cortex, but it is unclear whether attention to different acoustic features, such as voice pitch and speaker location, modulates subcortical activity. Studies using a dichotic listening paradigm indicated that auditory brainstem processing may be modulated by the direction of attention. We investigated whether endogenous selective attention to one of two speech signals affects amplitude and phase locking in auditory brainstem responses when the signals were either discriminable by frequency content alone, or by frequency content and spatial location. Frequency-following responses to the speech sounds were significantly modulated in both conditions. The modulation was specific to the task-relevant frequency band. The effect was stronger when both frequency and spatial information were available. Patterns of response were variable between participants, and were correlated with psychophysical discriminability of the stimuli, suggesting that the modulation was biologically relevant. Our results demonstrate that auditory brainstem responses are susceptible to efferent modulation related to behavioral goals. Furthermore they suggest that mechanisms of selective attention actively shape activity at early subcortical processing stages according to task relevance and based on frequency and spatial cues.

  7. Mode-locking neurodynamics predict human auditory brainstem responses to musical intervals.

    Science.gov (United States)

    Lerud, Karl D; Almonte, Felix V; Kim, Ji Chul; Large, Edward W

    2014-02-01

    The auditory nervous system is highly nonlinear. Some nonlinear responses arise through active processes in the cochlea, while others may arise in neural populations of the cochlear nucleus, inferior colliculus and higher auditory areas. In humans, auditory brainstem recordings reveal nonlinear population responses to combinations of pure tones, and to musical intervals composed of complex tones. Yet the biophysical origin of central auditory nonlinearities, their signal processing properties, and their relationship to auditory perception remain largely unknown. Both stimulus components and nonlinear resonances are well represented in auditory brainstem nuclei due to neural phase-locking. Recently mode-locking, a generalization of phase-locking that implies an intrinsically nonlinear processing of sound, has been observed in mammalian auditory brainstem nuclei. Here we show that a canonical model of mode-locked neural oscillation predicts the complex nonlinear population responses to musical intervals that have been observed in the human brainstem. The model makes predictions about auditory signal processing and perception that are different from traditional delay-based models, and may provide insight into the nature of auditory population responses. We anticipate that the application of dynamical systems analysis will provide the starting point for generic models of auditory population dynamics, and lead to a deeper understanding of nonlinear auditory signal processing possibly arising in excitatory-inhibitory networks of the central auditory nervous system. This approach has the potential to link neural dynamics with the perception of pitch, music, and speech, and lead to dynamical models of auditory system development. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. for ABR Service

    Directory of Open Access Journals (Sweden)

    Mohsen Hosamo

    2012-01-01

    Full Text Available This paper describes modeling of the available bit rate (ABR source traffic in asynchronous transfer mode (ATM network using BLPos/GTEXP traffic generator, which employs Poisson distribution for modeling the burst length (BLPos and exponential distribution for modeling the gap time (GTEXP. This traffic generator inherits the advantages of both Poisson and exponential distribution functions to achieve enhanced link performance. Analytical and simulation results for BLPos/GTEXP traffic generator have been presented and compared.

  9. Potenciais evocados auditivos de tronco encefálico em frentistas Auditory brainstem response in gas station attendants

    Directory of Open Access Journals (Sweden)

    Lenita da Silva Quevedo

    2012-12-01

    Full Text Available A ototoxidade dos solventes orgânicos pode atingir o sistema auditivo a nível coclear e retrococlear. OBJETIVO: Avaliar a integridade neurofisiológica do sistema auditivo até tronco cerebral por meio do PEATE. MÉTODO: Estudo prospectivo. Estudados frentistas de três postos de gasolina da cidade de Santa Maria/RS. A amostra ficou composta por 21 sujeitos, que foram avaliados por meio de potenciais evocados auditivos de tronco encefálico. RESULTADOS: Alteração nas latências absolutas das ondas I e III e em todas as latências interpicos, na orelha direita. Na orelha esquerda houve alteração na latência absoluta de todas as ondas, e em todos os intervalos interpicos. Alteração na diferença interaural da onda V foi verificada em 19% dos sujeitos. No grupo exposto há mais de cinco anos, foram estatisticamente significantes o número de sujeitos com alteração: no intervalo interpico I-V da orelha direita; na latência absoluta da onda I e no intervalo interpico III-V da orelha esquerda. CONCLUSÃO: A exposição a combustíveis pode causar alterações no sistema auditivo central.Ototoxicity of organic solvents can affect the hearing system up to the cochlea level and the central structures of hearing. OBJECTIVE: To evaluate the neurophysiological integrity of the hearing system in subjects exposed to fuels using ABR. METHOD: Prospective study. We evaluated attendants from three gas stations in Santa Maria/RS. The sample had 21 subjects, who were evaluated by auditory brainstem response. RESULTS: We found an alteration in the absolute latencies of Waves I and III and in all the interpeak latencies, in the right ear. In the left ear there was a change in the absolute latencies of all Waves, and in all the interpeak intervals. A change in the interaural difference of Wave V was found in 19% of the individuals. In the group exposed for more than five years, there were subjects with a statistically significant changes: in the I

  10. DESCRIPTION OF BRAINSTEM AUDITORY EVOKED RESPONSES (AIR AND BONE CONDUCTION IN CHILDREN WITH NORMAL HEARING

    Directory of Open Access Journals (Sweden)

    A. V. Pashkov

    2014-01-01

    Full Text Available Diagnosis of hearing level in small children with conductive hearing loss associated with congenital craniofacial abnormalities, particularly with agenesis of external ear and external auditory meatus is a pressing issue. Conventional methods of assessing hearing in the first years of life, i. e. registration of brainstem auditory evoked responses to acoustic stimuli in the event of air conduction, does not give an indication of the auditory analyzer’s condition due to potential conductive hearing loss in these patients. This study was aimed at assessing potential of diagnosing the auditory analyzer’s function with registering brainstem auditory evoked responses (BAERs to acoustic stimuli transmitted by means of a bone vibrator. The study involved 17 children aged 3–10 years with normal hearing. We compared parameters of registering brainstem auditory evoked responses (peak V depending on the type of stimulus transmission (air/bone in children with normal hearing. The data on thresholds of the BAERs registered to acoustic stimuli in the event of air and bone conduction obtained in this study are comparable; hearing thresholds in the event of acoustic stimulation by means of a bone vibrator correlates with the results of the BAERs registered to the stimuli transmitted by means of air conduction earphones (r = 0.9. High correlation of thresholds of BAERs to the stimuli transmitted by means of a bone vibrator with thresholds of BAERs registered when air conduction earphones were used helps to assess auditory analyzer’s condition in patients with any form of conductive hearing loss.  

  11. Transient evoked otoacoustic emissions and auditory brainstem response in infants with perinatal asphyxia.

    Science.gov (United States)

    Ribeiro, Georgea Espindola; Silva, Daniela Polo Camargo da; Montovani, Jair Cortez

    2016-10-01

    The objective of this study was to verify the effects of perinatal asphyxia on different parts of the auditory system. This was a non-concurrent cohort study conducted on a fixed population in a tertiary public hospital. Participants included 181 infants born at term who underwent the transient evoked otoacoustic emission test as a part of a neonatal hearing screening program, with a "pass" result in both ears, and by auditory brainstem response testing. The infants were divided into 3 groups: G1, 20 infants who had perinatal asphyxia; G2, 111 infants with an Apgar score lower than 4 in the first minute and/or lower than 6 in the fifth minute (called "low Apgar" at birth); and G3, 50 infants with first- and fifth-minute Apgar scores ≥7. The signal-to-noise ratio of transient evoked otoacoustic emissions were greater in G3 compared with G1 and G2 at 4 kHz frequency for males. An increased latency of waves I and III in the auditory brainstem response of male infants in G1 was observed. This study demonstrated that alterations occurred in both the cochlear and the neural components in male infants who had perinatal asphyxia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Effect of hearing aids use on speech stimulus decoding through speech-evoked ABR.

    Science.gov (United States)

    Leite, Renata Aparecida; Magliaro, Fernanda Cristina Leite; Raimundo, Jeziela Cristina; Gândara, Mara; Garbi, Sergio; Bento, Ricardo Ferreira; Matas, Carla Gentile

    2016-12-08

    The electrophysiological responses obtained with the complex auditory brainstem response (cABR) provide objective measures of subcortical processing of speech and other complex stimuli. The cABR has also been used to verify the plasticity in the auditory pathway in the subcortical regions. To compare the results of cABR obtained in children using hearing aids before and after 9 months of adaptation, as well as to compare the results of these children with those obtained in children with normal hearing. Fourteen children with normal hearing (Control Group - CG) and 18 children with mild to moderate bilateral sensorineural hearing loss (Study Group - SG), aged 7-12 years, were evaluated. The children were submitted to pure tone and vocal audiometry, acoustic immittance measurements and ABR with speech stimulus, being submitted to the evaluations at three different moments: initial evaluation (M0), 3 months after the initial evaluation (M3) and 9 months after the evaluation (M9); at M0, the children assessed in the study group did not use hearing aids yet. When comparing the CG and the SG, it was observed that the SG had a lower median for the V-A amplitude at M0 and M3, lower median for the latency of the component V at M9 and a higher median for the latency of component O at M3 and M9. A reduction in the latency of component A at M9 was observed in the SG. Children with mild to moderate hearing loss showed speech stimulus processing deficits and the main impairment is related to the decoding of the transient portion of this stimulus spectrum. It was demonstrated that the use of hearing aids promoted neuronal plasticity of the Central Auditory Nervous System after an extended time of sensory stimulation. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  13. Effect of hearing aids use on speech stimulus decoding through speech-evoked ABR

    Directory of Open Access Journals (Sweden)

    Renata Aparecida Leite

    Full Text Available Abstract Introduction The electrophysiological responses obtained with the complex auditory brainstem response (cABR provide objective measures of subcortical processing of speech and other complex stimuli. The cABR has also been used to verify the plasticity in the auditory pathway in the subcortical regions. Objective To compare the results of cABR obtained in children using hearing aids before and after 9 months of adaptation, as well as to compare the results of these children with those obtained in children with normal hearing. Methods Fourteen children with normal hearing (Control Group - CG and 18 children with mild to moderate bilateral sensorineural hearing loss (Study Group - SG, aged 7-12 years, were evaluated. The children were submitted to pure tone and vocal audiometry, acoustic immittance measurements and ABR with speech stimulus, being submitted to the evaluations at three different moments: initial evaluation (M0, 3 months after the initial evaluation (M3 and 9 months after the evaluation (M9; at M0, the children assessed in the study group did not use hearing aids yet. Results When comparing the CG and the SG, it was observed that the SG had a lower median for the V-A amplitude at M0 and M3, lower median for the latency of the component V at M9 and a higher median for the latency of component O at M3 and M9. A reduction in the latency of component A at M9 was observed in the SG. Conclusion Children with mild to moderate hearing loss showed speech stimulus processing deficits and the main impairment is related to the decoding of the transient portion of this stimulus spectrum. It was demonstrated that the use of hearing aids promoted neuronal plasticity of the Central Auditory Nervous System after an extended time of sensory stimulation.

  14. Electrically-evoked frequency-following response (EFFR in the auditory brainstem of guinea pigs.

    Directory of Open Access Journals (Sweden)

    Wenxin He

    Full Text Available It is still a difficult clinical issue to decide whether a patient is a suitable candidate for a cochlear implant and to plan postoperative rehabilitation, especially for some special cases, such as auditory neuropathy. A partial solution to these problems is to preoperatively evaluate the functional integrity of the auditory neural pathways. For evaluating the strength of phase-locking of auditory neurons, which was not reflected in previous methods using electrically evoked auditory brainstem response (EABR, a new method for recording phase-locking related auditory responses to electrical stimulation, called the electrically evoked frequency-following response (EFFR, was developed and evaluated using guinea pigs. The main objective was to assess feasibility of the method by testing whether the recorded signals reflected auditory neural responses or artifacts. The results showed the following: 1 the recorded signals were evoked by neuron responses rather than by artifact; 2 responses evoked by periodic signals were significantly higher than those evoked by the white noise; 3 the latency of the responses fell in the expected range; 4 the responses decreased significantly after death of the guinea pigs; and 5 the responses decreased significantly when the animal was replaced by an electrical resistance. All of these results suggest the method was valid. Recording obtained using complex tones with a missing fundamental component and using pure tones with various frequencies were consistent with those obtained using acoustic stimulation in previous studies.

  15. Nonlinear feature extraction for objective classification of complex auditory brainstem responses to diotic perceptually critical consonant-vowel syllables.

    Science.gov (United States)

    Jafarpisheh, Amir Salar; Jafari, Amir Homayoun; Abolhassani, Mohammadjavad; Farhadi, Mohammad; Sadjedi, Hamed; Pourbakht, Akram; Shirzhiyan, Zahra

    2016-02-01

    To examine if nonlinear feature extraction method yields appropriate results in complex brainstem response classification of three different consonant vowels diotically presented in normal Persian speaking adults. Speech-evoked auditory brainstem responses were obtained in 27 normal hearing young adults by using G.tec EEG recording system. 170ms synthetic consonant-vowel stimuli /ba/, /da/, /ga/ were presented binaurally and the recurrence quantification analysis was performed on the responses. The recurrence time of second type was proposed as a suitable feature. ANOVA was also used for testing the significance of extracted feature. Post-comparison statistical method was used for showing which means are significantly different from each other. Dimension embedding and state space reconstruction were helpful for visualizing nonlinearity in auditory system. The proposed feature was successful in the objective classification of responses in window time 20.1-35.3ms, which belonged to formant transition period of stimuli. Also the p value behavior of recurrence time of second type feature as a discriminant feature was close to the nature of the response that includes transient and sustained parts. On the other hand, the /ba/ and /ga/ classification period was wider than the others. The extracted feature shown in this paper is helpful for the objective of distinguishing individuals with auditory processing disorders in the structurally similar voices. On the other hand, differing nonlinear feature is meaningful in a special region of response, equal to formant transition period, and this feature is related to the state space changes of brainstem response. It can be assumed that more information is within this region of signal and it is a sign of processing role of brainstem. The state changes of system are dependent on input stimuli, so the existence of top down feedback from cortex to brainstem forces the system to act differently. Copyright © 2015 Elsevier Ireland Ltd

  16. Thresholds of Tone Burst Auditory Brainstem Responses for Infants and Young Children with Normal Hearing in Taiwan

    Directory of Open Access Journals (Sweden)

    Chung-Yi Lee

    2007-10-01

    Conclusion: Based on the published research and our study, we suggest setting the normal criterion levels for infants and young children in Taiwan of the tone burst auditory brainstem response to air-conducted tones as 30 dB nHL for 500 and 1000 Hz, and 25 dB nHL for 2000 and 4000 Hz.

  17. LS CE-Chirp® vs. Click in the neuroaudiological diagnosis by ABR.

    Science.gov (United States)

    Cargnelutti, Michelle; Cóser, Pedro Luis; Biaggio, Eliara Pinto Vieira

    The chirp stimulus was developed seeking to counterbalance the delay of the sound wave on its journey through the cochlea, allowing the hair cells to depolarize at the same time. The result is a simultaneous stimulation providing better neural synchrony and, consequently, the recording of responses with greater amplitudes. To compare the absolute latency of waves I, III and V, the interpeak intervals I-III, III-V and I-V, amplitude values of wave V and its association with the amplitude of wave I, and the interaural difference V-V in the auditory brainstem response (ABR) using Click and LS CE-Chirp ® stimuli to determine whether the responses evoked by LS CE-Chirp ® could be applied to neuroaudiological diagnosis. Cross-sectional study with 30 normal-hearing individuals. The parameters used were: intensity of 85dBnHL, alternating polarity; 17.1 stimuli/s and 100-3000Hz filters. The absolute latencies of waves I, III and V observed with LS CE-Chirp ® and click did not show significant differences. Significantly higher amplitudes of wave V were observed with the LS CE-Chirp ® . The interaural difference between the wave V latencies between stimuli showed no significant difference. The LS CE-Chirp ® stimulus was shown to be as efficient as the click to capture ABR at high levels of stimulation, with the advantage of producing greater-amplitude V waves. Copyright © 2016. Published by Elsevier Editora Ltda.

  18. Modification of Hypoxic Respiratory Response by Protein Tyrosine Kinase in Brainstem Ventral Respiratory Neuron Group.

    Science.gov (United States)

    Wang, Hui; Huai, Ruituo; Yang, Junqing; Li, Yanchun

    2016-01-01

    Protein tyrosine kinase (PTK) mediated the tyrosine phosphorylation modification of neuronal receptors and ion channels. Whether such modification resulted in changes of physiological functions was not sufficiently studied. In this study we examined whether the hypoxic respiratory response-which is the enhancement of breathing in hypoxic environment could be affected by the inhibition of PTK at brainstem ventral respiratory neuron column (VRC). Experiments were performed on urethane anesthetized adult rabbits. Phrenic nerve discharge was recorded as the central respiratory motor output. Hypoxic respiratory response was produced by ventilating the rabbit with 10% O2-balance 90% N2 for 5 minutes. The responses of phrenic nerve discharge to hypoxia were observed before and after microinjecting PTK inhibitor genistein, AMPA receptor antagonist CNQX, or inactive PTK inhibitor analogue daidzein at the region of ambiguus nucleus (NA) at levels 0-2 mm rostral to obex where the inspiratory subgroup of VRC were recorded. Results were as follows: 1. the hypoxic respiratory response was significantly attenuated after microinjection of genistein and/or CNQX, and no additive effect (i.e., further attenuation of hypoxic respiratory response) was observed when genistein and CNQX were microinjected one after another at the same injection site. Microinjection of daidzein had no effect on hypoxic respiratory response. 2. Fluorescent immunostaining showed that hypoxia significantly increased the number of phosphotyrosine immunopositive neurons in areas surrounding NA and most of these neurons were also immunopositive to glutamate AMPA receptor subunit GluR1. These results suggested that PTK played an important role in regulating the hypoxic respiratory response, possibly through the tyrosine phosphorylation modification of glutamate AMPA receptors on the respiratory neurons of ventral respiratory neuron column.

  19. [Auditory brainstem response testing revisit of infants who failed the hearing screening].

    Science.gov (United States)

    Xin, Rong; Lou, Zhiwu; Lei, Zhaoxia

    2008-11-01

    Analyze the ABR testing results of local infants who failed the hearing screening and summarize its characteristics. Carry on the first ABR test to 140 infants who failed the newborns' hearing screening when they are about 3-month age, the unusualities carry on the second ABR test at about 6-month age, and carry on the statistical analysis. One hundred and forty infants with the first ABR diagnosis, 65 infants are normal, accounting for 46.43%; 75 infants have single or binaural ear hearing disorder, accounting for 53.57%, single ear 17.14%, binaural ear 36.43%, of which mild hearing disorder takes most, accounting for 27.14%, the profound hearing loss is also not extremely rare, accounting for 14.29%. Between male and female hearing disorder disease incidence rate difference is not remarkable statistics significance (P > 0.05). Between the number of high-risk in the hearing injury and non-high-risk after the comparison difference is not remarkable statistical significance (P > 0.05). With the population of above severe loss in hearing high-risk has the remarkable statistical significance with the non-high-risk comparison difference (P brain paralysis profound hearing disorder extension converges normally extremely. The non-high-risk whose hearing changes for the better is obviously higher than high-risk (P child hearing situation appraisal should be prudent to the brain paralysis; should establish perfect tracing, revisiting and managing system as soon as possible.

  20. Synchronized Progression of Prestin Expression and Auditory Brainstem Response during Postnatal Development in Rats

    Directory of Open Access Journals (Sweden)

    Jianfeng Hang

    2016-01-01

    Full Text Available Prestin is the motor protein expressed in the cochlear outer hair cells (OHCs of mammalian inner ear. The electromotility of OHCs driven by prestin is responsible for the cochlear amplification which is required for normal hearing in adult animals. Postnatal expression of prestin and activity of OHCs may contribute to the maturation of hearing in rodents. However, the temporal and spatial expression of prestin in cochlea during the development is not well characterized. In the present study, we examined the expression and function of prestin from the OHCs in apical, middle, and basal turns of the cochleae of postnatal rats. Prestin first appeared at postnatal day 6 (P6 for basal turn, P7 in middle turn, and P9 for apical turn of cochlea. The expression level increased progressively over the next few days and by P14 reached the mature level for all three segments. By comparison with the time course of the development of auditory brainstem response for different frequencies, our data reveal that prestin expression synchronized with the hearing development. The present study suggests that the onset time of hearing may require the expression of prestin and is determined by the mature function of OHCs.

  1. Enhanced auditory brainstem response and parental bonding style in children with gastrointestinal symptoms.

    Directory of Open Access Journals (Sweden)

    Shizuka Seino

    Full Text Available The electrophysiological properties of the brain and influence of parental bonding in childhood irritable bowel syndrome (IBS are unclear. We hypothesized that children with chronic gastrointestinal (GI symptoms like IBS may show exaggerated brainstem auditory evoked potential (BAEP responses and receive more inadequate parental bonding.Children aged seven and their mothers (141 pairs participated. BAEP was measured by summation of 1,000 waves of the electroencephalogram triggered by 75 dB click sounds. The mothers completed their Children's Somatization Inventory (CSI and Parental Bonding Instrument (PBI. CSI results revealed 66 (42% children without GI symptoms (controls and 75 (58% children with one or more GI symptoms (GI group. The III wave in the GI group (median 4.10 interquartile range [3.95-4.24] ms right, 4.04 [3.90-4.18] ms left had a significantly shorter peak latency than controls (4.18 [4.06-4.34] ms right, p = 0.032, 4.13 [4.02-4.24] ms left, p = 0.018. The female GI group showed a significantly shorter peak latency of the III wave (4.00 [3.90-4.18] ms than controls (4.18 [3.97-4.31] ms, p = 0.034 in the right side. BAEP in the male GI group did not significantly differ from that in controls. GI scores showed a significant correlation with the peak latency of the III wave in the left side (rho = -0.192, p = 0.025. The maternal care PBI scores in the GI group (29 [26]-[33] were significantly lower than controls (31 [28.5-33], p = 0.010, while the maternal over-protection PBI scores were significantly higher in the GI group (16 [12]-[17] than controls (13 [10.5-16], p = 0.024. Multiple regression analysis in females also supported these findings.It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms.

  2. Auditory Brainstem Response Wave Amplitude Characteristics as a Diagnostic Tool in Children with Speech Delay with Unknown Causes

    Directory of Open Access Journals (Sweden)

    Susan Abadi

    2016-09-01

    Full Text Available Speech delay with an unknown cause is a problem among children. This diagnosis is the last differential diagnosis after observing normal findings in routine hearing tests. The present study was undertaken to determine whether auditory brainstem responses to click stimuli are different between normally developing children and children suffering from delayed speech with unknown causes. In this cross-sectional study, we compared click auditory brainstem responses between 261 children who were clinically diagnosed with delayed speech with unknown causes based on normal routine auditory test findings and neurological examinations and had >12 months of speech delay (case group and 261 age- and sex-matched normally developing children (control group. Our results indicated that the case group exhibited significantly higher wave amplitude responses to click stimuli (waves I, III, and V than did the control group (P=0.001. These amplitudes were significantly reduced after 1 year (P=0.001; however, they were still significantly higher than those of the control group (P=0.001. The significant differences were seen regardless of the age and the sex of the participants. There were no statistically significant differences between the 2 groups considering the latency of waves I, III, and V. In conclusion, the higher amplitudes of waves I, III, and V, which were observed in the auditory brainstem responses to click stimuli among the patients with speech delay with unknown causes, might be used as a diagnostic tool to track patients’ improvement after treatment.

  3. Test-Retest Reliability of Dual-Recorded Brainstem versus Cortical Auditory-Evoked Potentials to Speech.

    Science.gov (United States)

    Bidelman, Gavin M; Pousson, Monique; Dugas, Calli; Fehrenbach, Amy

    2018-02-01

    Auditory-evoked potentials have proven useful in the objective evaluation of sound encoding at different stages of the auditory pathway (brainstem and cortex). Yet, their utility for use in clinical assessment and empirical research relies critically on the precision and test-retest repeatability of the measure. To determine how subcortical/cortical classes of auditory neural responses directly compare in terms of their internal consistency and test-retest reliability within and between listeners. A descriptive cohort study describing the dispersion of electrophysiological measures. Eight young, normal-hearing female listeners. We recorded auditory brainstem responses (ABRs), brainstem frequency-following responses (FFRs), and cortical (P1-N1-P2) auditory-evoked potentials elicited by speech sounds in the same set of listeners. We reassessed responses within each of four different test sessions over a period of 1 mo, allowing us to detect possible changes in latency/amplitude characteristics with finer detail than in previous studies. Our findings show that brainstem and cortical amplitude/latency measures are remarkably stable; with the exception of slight prolongation of the P1 wave, we found no significant variation in any response measure. Intraclass correlation analysis revealed that the speech-evoked FFR amplitude and latency measures achieved superior repeatability (intraclass correlation coefficient >0.85) among the more widely used obligatory brainstem (ABR) and cortical (P1-N1-P2) auditory-evoked potentials. Contrasting these intersubject effects, intrasubject variability (i.e., within-subject coefficient of variation) revealed that while latencies were more stable than amplitudes, brainstem and cortical responses did not differ in their variability at the single subject level. We conclude that (1) the variability of auditory neural responses increases with ascending level along the auditory neuroaxis (cortex > brainstem) between subjects but remains

  4. Stereotactic Radiosurgery for Brainstem Metastases: An International Cooperative Study to Define Response and Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Trifiletti, Daniel M., E-mail: daniel.trifiletti@gmail.com [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia (United States); Lee, Cheng-Chia [Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan (China); Kano, Hideyuki; Cohen, Jonathan [Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Janopaul-Naylor, James; Alonso-Basanta, Michelle; Lee, John Y.K. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Simonova, Gabriela; Liscak, Roman [Department of Radiation and Stereotactic Neurosurgery, Na Homolce Hospital, Prague (Czech Republic); Wolf, Amparo; Kvint, Svetlana [Department of Neurosurgery, New York University Lagone Medical Center, New York, New York (United States); Grills, Inga S.; Johnson, Matthew [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan (United States); Liu, Kang-Du; Lin, Chung-Jung [Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan (China); Mathieu, David; Héroux, France [Division of Neurosurgery, Université de Sherbrooke, Centre de recherche du CHUS, Sherbrooke, Québec (Canada); Silva, Danilo; Sharma, Mayur [Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States); Cifarelli, Christopher P. [Departments of Neurosurgery and Radiation Oncology, West Virginia University, Morgantown, West Virginia (United States); and others

    2016-10-01

    Purpose: To pool data across multiple institutions internationally and report on the cumulative experience of brainstem stereotactic radiosurgery (SRS). Methods and Materials: Data on patients with brainstem metastases treated with SRS were collected through the International Gamma Knife Research Foundation. Clinical, radiographic, and dosimetric characteristics were compared for factors prognostic for local control (LC) and overall survival (OS) using univariate and multivariate analyses. Results: Of 547 patients with 596 brainstem metastases treated with SRS, treatment of 7.4% of tumors resulted in severe SRS-induced toxicity (grade ≥3, increased odds with increasing tumor volume, margin dose, and whole-brain irradiation). Local control at 12 months after SRS was 81.8% and was improved with increasing margin dose and maximum dose. Overall survival at 12 months after SRS was 32.7% and impacted by age, gender, number of metastases, tumor histology, and performance score. Conclusions: Our study provides additional evidence that SRS has become an option for patients with brainstem metastases, with an excellent benefit-to-risk ratio in the hands of experienced clinicians. Prior whole-brain irradiation increases the risk of severe toxicity in brainstem metastasis patients undergoing SRS.

  5. Type -2 diabetes mellitus and auditory brainstem responses-a hospital based study.

    Science.gov (United States)

    Gupta, Rahul; Aslam, Mohd; Hasan, Sa; Siddiqi, Ss

    2010-01-01

    Diabetes mellitus comprises a group of common metabolic disorders that share the phenotype of hyperglycemia. The metabolic dysregulation associated with DM causes secondary patho-physiological changes in multiple organ systems. The brainstem auditory electric responses represent a useful, non invasive and simple procedure to detect both acoustic nerve and CNS damage. MATERIAL #ENTITYSTARTX00026; The study was carried out in the department of ENT, JNMC from 2008 -2010. The study included two groups, (i) diabetic group (n=25) (ii) Control group (n = 25). Diabetic group included patients attending Endocrinology OPD and ward. The equipment used for recording evoked response audiometry is IHS-BERA. Model number TH72312HT. Year of manufacture 2006. Mean age of control group was 45.7 years. In the study group 13 (52%) were males where as 12 (48%) were females. Mean age of study group was 46.8 years. There is no significant difference between age groups of controls and cases. Significant difference was found in latencies of wave III and interpeak III-V while highly significant difference was found in latencies of wave V and interpeak I-III, I-V between control and study group at 70 dB. Highly significant difference was found in latencies of wave III, V and interpeak I-III and I-V while significant difference was found in interwave III-V between control and study group at 80 dB. Significant difference was found in latencies of wave V and interpeak III-V while highly significant difference was found in wave III and interpeak I-III, I-V between control and study group at 90 dB. BERA is a simple, non-invasive procedure to detect early impairment of acoustic nerve, and CNS pathways, even in the absence of specific symptoms. This study suggests that if BERA is carried out in diabetic patients; involvement of central neuronal axis can be detected earlier.

  6. ABR Audiometry in Cornelia De Lange Syndrome.

    Science.gov (United States)

    Brown, Denice P.

    Eight children (ages 13 days to 5 years) with a diagnosis of Cornelia de Lange syndrome received audiologic evaluation consisting of immittance audiometry and auditory brainstem response audiometry to air and bone conducted "click" stimuli, as behavioral testing was unreliable due to patient age and/or developmental delay. Developmental…

  7. ABR Examinations: The Why, What, and How

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Gary J.; Bosma, Jennifer L., E-mail: jbosma@theabr.org; Guiberteau, Milton J.; Gerdeman, Anthony M.; Frush, Donald P.; Borgstede, James P.

    2013-10-01

    The American Board of Radiology (ABR) has provided certification for diagnostic radiologists and other specialists and subspecialists for more than 75 years. The Board certification process is a tangible expression of the social contract between the profession and the public by which the profession enjoys the privilege of self-regulation and the public is assured that it can expect medical professionals to put patients' interests first, guarantees the competence of practitioners, and guards the public health. A primary tool used by the ABR in fulfilling this responsibility is the secure proctored examination. This article sets forth seven standards based on authoritative sources in the field of psychometrics (the science of mental measurements), and explains in each case how the ABR implements that standard. Readers are encouraged to understand that, despite the multiple opinions that may be held, these standards developed over decades by experts using the scientific method should be the central feature in any discussion or critique of examinations given for the privilege of professional practice and for safeguarding the public well-being.

  8. ABR Examinations: The Why, What, and How

    International Nuclear Information System (INIS)

    Becker, Gary J.; Bosma, Jennifer L.; Guiberteau, Milton J.; Gerdeman, Anthony M.; Frush, Donald P.; Borgstede, James P.

    2013-01-01

    The American Board of Radiology (ABR) has provided certification for diagnostic radiologists and other specialists and subspecialists for more than 75 years. The Board certification process is a tangible expression of the social contract between the profession and the public by which the profession enjoys the privilege of self-regulation and the public is assured that it can expect medical professionals to put patients' interests first, guarantees the competence of practitioners, and guards the public health. A primary tool used by the ABR in fulfilling this responsibility is the secure proctored examination. This article sets forth seven standards based on authoritative sources in the field of psychometrics (the science of mental measurements), and explains in each case how the ABR implements that standard. Readers are encouraged to understand that, despite the multiple opinions that may be held, these standards developed over decades by experts using the scientific method should be the central feature in any discussion or critique of examinations given for the privilege of professional practice and for safeguarding the public well-being

  9. Brainstem auditory evoked responses in an equine patient population: part I--adult horses.

    Science.gov (United States)

    Aleman, M; Holliday, T A; Nieto, J E; Williams, D C

    2014-01-01

    Brainstem auditory evoked response has been an underused diagnostic modality in horses as evidenced by few reports on the subject. To describe BAER findings, common clinical signs, and causes of hearing loss in adult horses. Study group, 76 horses; control group, 8 horses. Retrospective. BAER records from the Clinical Neurophysiology Laboratory were reviewed from the years of 1982 to 2013. Peak latencies, amplitudes, and interpeak intervals were measured when visible. Horses were grouped under disease categories. Descriptive statistics and a posthoc Bonferroni test were performed. Fifty-seven of 76 horses had BAER deficits. There was no breed or sex predisposition, with the exception of American Paint horses diagnosed with congenital sensorineural deafness. Eighty-six percent (n = 49/57) of the horses were younger than 16 years of age. The most common causes of BAER abnormalities were temporohyoid osteoarthropathy (THO, n = 20/20; abnormalities/total), congenital sensorineural deafness in Paint horses (17/17), multifocal brain disease (13/16), and otitis media/interna (4/4). Auditory loss was bilateral and unilateral in 74% (n = 42/57) and 26% (n = 15/57) of the horses, respectively. The most common causes of bilateral auditory loss were sensorineural deafness, THO, and multifocal brain disease whereas THO and otitis were the most common causes of unilateral deficits. Auditory deficits should be investigated in horses with altered behavior, THO, multifocal brain disease, otitis, and in horses with certain coat and eye color patterns. BAER testing is an objective and noninvasive diagnostic modality to assess auditory function in horses. Copyright © 2014 by the American College of Veterinary Internal Medicine.

  10. The influence of cochlear traveling wave and neural adaptation on auditory brainstem responses

    DEFF Research Database (Denmark)

    Junius, D.; Dau, Torsten

    2005-01-01

    . This nonlinearity in terms of temporal processing most likely reflects effects of short-term adaptation. Overall, the results of the present study further demonstrate the importance of cochlear processing for the formation of brainstem potentials. The data may provide constraints on future models of peripheral...

  11. Differences in Brainstem Fiber Tract Response to Radiation: A Longitudinal Diffusion Tensor Imaging Study

    International Nuclear Information System (INIS)

    Uh, Jinsoo; Merchant, Thomas E.; Li, Yimei; Feng, Tianshu; Gajjar, Amar; Ogg, Robert J.; Hua, Chiaho

    2013-01-01

    Purpose: To determine whether radiation-induced changes in white matter tracts are uniform across the brainstem. Methods and Materials: We analyzed serial diffusion tensor imaging data, acquired before radiation therapy and over 48 to 72 months of follow-up, from 42 pediatric patients (age 6-20 years) with medulloblastoma. FSL software (FMRIB, Oxford, UK) was used to calculate fractional anisotropy (FA) and axial, radial, and mean diffusivities. For a consistent identification of volumes of interest (VOIs), the parametric maps of each patient were transformed to a standard brain space (MNI152), on which we identified VOIs including corticospinal tract (CST), medial lemniscus (ML), transverse pontine fiber (TPF), and middle cerebellar peduncle (MCP) at the level of pons. Temporal changes of DTI parameters in VOIs were compared using a linear mixed effect model. Results: Radiation-induced white matter injury was marked by a decline in FA after treatment. The decline was often accompanied by decreased axial diffusivity, increased radial diffusivity, or both. This implied axonal damage and demyelination. We observed that the magnitude of the changes was not always uniform across substructures of the brainstem. Specifically, the changes in DTI parameters for TPF were more pronounced than in other regions (P .093 for all parameters). Conclusions: Changes in the structural integrity of white matter tracts, assessed by DTI, were not uniform across the brainstem after radiation therapy. These results support a role for tract-based assessment in radiation treatment planning and determination of brainstem tolerance

  12. Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants

    OpenAIRE

    Keefe, Douglas H.; Gorga, Michael P.; Jesteadt, Walt; Smith, Lynette M.

    2008-01-01

    In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the rig...

  13. Combined laryngeal inflammation and trauma mediate long-lasting immunoreactivity response in the brainstem sensory nuclei in the rat

    Directory of Open Access Journals (Sweden)

    Kristina eSimonyan

    2012-11-01

    Full Text Available Somatosensory feedback from the larynx plays a critical role in regulation of normal upper airway functions, such as breathing, deglutition and voice production, while altered laryngeal sensory feedback is known to elicit a variety of pathological reflex responses, including persistent coughing, dysphonia and laryngospasm. Despite its clinical impact, the central mechanisms underlying the development of pathological laryngeal responses remain poorly understood. We examined the effects of persistent vocal fold (VF inflammation and trauma, as frequent causes of long-lasting modulation of laryngeal sensory feedback, on brainstem immunoreactivity in the rat. Combined VF inflammation and trauma were induced by injection of lipopolysaccharide (LPS solution and compared to VF trauma alone from injection of vehicle solution and to controls without any VF manipulations. Using a c-fos marker, we found significantly increased Fos-like immunoreactivity (FLI in the bilateral intermediate/parvicellular reticular formation (IRF/PCRF with a trend in the left solitary tract nucleus (NTS only in animals with LPS-induced VF inflammation and trauma. Further, FLI in the right NTS was significantly correlated with the severity of LPS-induced VF changes. However, increased brainstem FLI response was not associated with FLI changes in the first-order neurons of the laryngeal afferents located in the nodose and jugular ganglia in either group. Our data indicate that complex VF alterations (i.e., inflammation/trauma vs. trauma alone may cause prolonged excitability of the brainstem nuclei receiving a direct sensory input from the larynx, which, in turn, may lead to (malplastic changes within the laryngeal central sensory control.

  14. Neonatal hearing screening of high-risk infants using automated auditory brainstem response: a retrospective analysis of referral rates.

    LENUS (Irish Health Repository)

    McGurgan, I J

    2013-10-07

    The past decade has seen the widespread introduction of universal neonatal hearing screening (UNHS) programmes worldwide. Regrettably, such a programme is only now in the process of nationwide implementation in the Republic of Ireland and has been largely restricted to one screening modality for initial testing; namely transient evoked otoacoustic emissions (TEOAE). The aim of this study is to analyse the effects of employing a different screening protocol which utilises an alternative initial test, automated auditory brainstem response (AABR), on referral rates to specialist audiology services.

  15. Auditory brainstem and cortical potentials following bone-anchored hearing aid stimulation.

    Science.gov (United States)

    Rahne, Torsten; Ehelebe, Thomas; Rasinski, Christine; Götze, Gerrit

    2010-11-30

    Patients suffering from conductive or mixed hearing loss and Single-Sided Deafness may benefit from implantable hearing devices relying on bone conducted auditory stimulation. However, with only passively cooperative patients, objective methods are needed to estimate the aided and unaided pure-tone audiogram. This study focuses on the feasibility aspect of an electrophysiological determination of the hearing thresholds with bone-anchored hearing aid stimulation. Therefore, 10 normal-hearing subjects were provided with a Baha Intenso (Cochlear Ltd.) which was temporarily connected to the Baha Softband (Cochlear Ltd.). Auditory evoked potentials were measured by auditory stimulation paradigm used in clinical routine. The amplitudes, latencies, and thresholds of the resulting auditory brainstem responses (ABR) and the cortically evoked responses (CAEP) were correlated with the respective responses without the use of the Baha Intenso. The recording of ABR and CAEP by delivering the stimuli to the Baha results in response waveforms which are comparable to those evoked by earphone stimulation and appears appropriate to be measured using the Baha Intenso as stimulator. At the ABR recordings a stimulus artifact at higher stimulation levels and a constant latency shift caused by the Baha Intenso has to be considered. The CAEP recording appeared promising as a frequency specific objective method to approve the fitting of bone-anchored hearing aids. At all measurements, the ABR and CAEP thresholds seem to be consistent with the normal hearing of the investigated participants. Thus, a recording of auditory evoked potentials using a Baha is in general possible if specific limitations are considered. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Age-related hearing loss in dogs : Diagnosis with Brainstem-Evoked Response Audiometry and Treatment with Vibrant Soundbridge Middle Ear Implant.

    NARCIS (Netherlands)

    ter Haar, G.

    2009-01-01

    Age-related hearing loss (ARHL) is the most common cause of acquired hearing impairment in dogs. Diagnosis requires objective electrophysiological tests (brainstem evoked response audiometry [BERA]) evaluating the entire audible frequency range in dogs. In our laboratory a method was developed to

  17. Brainstem auditory evoked potentials with the use of acoustic clicks and complex verbal sounds in young adults with learning disabilities.

    Science.gov (United States)

    Kouni, Sophia N; Giannopoulos, Sotirios; Ziavra, Nausika; Koutsojannis, Constantinos

    2013-01-01

    Acoustic signals are transmitted through the external and middle ear mechanically to the cochlea where they are transduced into electrical impulse for further transmission via the auditory nerve. The auditory nerve encodes the acoustic sounds that are conveyed to the auditory brainstem. Multiple brainstem nuclei, the cochlea, the midbrain, the thalamus, and the cortex constitute the central auditory system. In clinical practice, auditory brainstem responses (ABRs) to simple stimuli such as click or tones are widely used. Recently, complex stimuli or complex auditory brain responses (cABRs), such as monosyllabic speech stimuli and music, are being used as a tool to study the brainstem processing of speech sounds. We have used the classic 'click' as well as, for the first time, the artificial successive complex stimuli 'ba', which constitutes the Greek word 'baba' corresponding to the English 'daddy'. Twenty young adults institutionally diagnosed as dyslexic (10 subjects) or light dyslexic (10 subjects) comprised the diseased group. Twenty sex-, age-, education-, hearing sensitivity-, and IQ-matched normal subjects comprised the control group. Measurements included the absolute latencies of waves I through V, the interpeak latencies elicited by the classical acoustic click, the negative peak latencies of A and C waves, as well as the interpeak latencies of A-C elicited by the verbal stimulus 'baba' created on a digital speech synthesizer. The absolute peak latencies of waves I, III, and V in response to monoaural rarefaction clicks as well as the interpeak latencies I-III, III-V, and I-V in the dyslexic subjects, although increased in comparison with normal subjects, did not reach the level of a significant difference (plearning disabilities' and who were characterized as with 'light' dyslexia according to dyslexia tests, no significant delays were found in peak latencies A and C and interpeak latencies A-C in comparison with the control group. Acoustic

  18. Hyperekplexia and trismus due to brainstem encephalopathy

    Science.gov (United States)

    Kellett, M.; Humphrey, P.; Tedman, B.; Steiger, M.

    1998-01-01

    The brainstem is said to be the generator of pathological startle responses due to reticular reflex myoclonus or hyperekplexia. A patient with facial weakness, nystagmus, and pyramidal tract signs had generalised reflex spasms in response to auditory, visual and tactile stimuli which clinically and neurophysiologically resembled hyperekplexia. The case is unusual because as well as hyperekplexia, the patient's initial presentation was with an equally rare manifestation of brainstem pathology—brainstem mediated trismus. The causes of brainstem trismus and exaggerated startle responses are discussed with respect to their underlying mechanisms. 

 PMID:9667574

  19. Characteristics of electrically evoked auditory brainstem responses in patients with cochlear nerve canal stenosis receiving cochlear implants.

    Science.gov (United States)

    Wang, Zhenxiao; Liu, Yun; Wang, Line; Shen, Xixi; Han, Shuguang; Wang, Wei; Gao, Fenqi; Liang, Wenqi; Peng, Kevin A

    2018-01-01

    To explore the characteristics of the electrically evoked auditory brainstem responses (EABR) in children with cochlear nerve canal stenosis (CNCs) following cochlear implantation (CI), and the EABR thresholds in children with stenotic versus normal cochlear nerve canals. Sixteen children with profound sensorineural hearing loss were included in this study: 8 with CNCs (CNCs group) and 8 with normal cochlear nerve canals (control group). All children underwent cochlear implantation with full insertion of all electrodes. EABR was performed 6 months postoperatively in both groups. The EABR extraction rate was 100% in children with normal cochlear nerve canals and only 50% in children with CNCs. EABR thresholds were significantly higher in children with CNCs of electrodes No. 11and 22 than in children with normal cochlear nerve canals (P  0.05 for all comparisons); while in the control group, the EABR threshold at electrode No 22 was lower than those at both electrodes No. 11 and 1 (P cochlear nerve canals vary according to the different locations of electrodes in the cochlea; while in children with CNCs, there was no significant difference among different electrode locations. The EABR thresholds in CNCs children were higher than those of children with normal cochlear nerve canals at electrode 11 and 22. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Sensorineural hearing loss among cerebellopontine-angle tumor patients examined with pure tone audiometry and brainstem-evoked response audiometry

    Science.gov (United States)

    Rinindra, A. M.; Zizlavsky, S.; Bashiruddin, J.; Aman, R. A.; Wulani, V.; Bardosono, S.

    2017-08-01

    Tumor in the cerebellopontine angle (CPA) accurs for approximately 5-10% of all intracranial tumors, where unilateral hearing loss and tinnitus are the most frequent symptoms. This study aimed to collect data on sensorineural hearing loss in CPA tumor patients in Dr. Cipto Mangunkusumo Hospital (CMH) using pure tone audiometry and brainstem-evoked response audiometry (BERA). It also aimed to obtaine data on CPA-tumor imaging through magnetic resonance imaging (MRI). This was a descriptive, analytic, and cross-sectional study. The subjects of this study were gathered using a total sampling method from secondary data between July 2012 and November 2016. From 104 patients, 30 matched the inclusion criteria. The CPA-tumor patients in the ENT CMH outpatient clinic were mostly female, middle-aged patients (41-60 years) whose clinical presentation was mostly tinnitus and severe, asymmetric sensorineural hearing loss in 10 subjects. From 30 subjects, 29 showed ipsilaterally impaired BERA results, and 17 subjects showed contralaterally impaired BERA results. There were 24 subjects who with large-sized tumors and 19 subjects who had intracanal tumors that had spread until they were extracanal in 19 subjects.

  1. Evaluation of deafness in American Paint Horses by phenotype, brainstem auditory-evoked responses, and endothelin receptor B genotype.

    Science.gov (United States)

    Magdesian, K Gary; Williams, D Colette; Aleman, Monica; Lecouteur, Richard A; Madigan, John E

    2009-11-15

    To evaluate deafness in American Paint Horses by phenotype, clinical findings, brainstem auditory-evoked responses (BAERs), and endothelin B receptor (EDNBR) genotype. Case series and case-control studies. 14 deaf American Paint Horses, 20 suspected-deaf American Paint Horses, and 13 nondeaf American Paint Horses and Pintos. Horses were categorized on the basis of coat color pattern and eye color. Testing for the EDNBR gene mutation (associated with overo lethal white foal syndrome) and BAERs was performed. Additional clinical findings were obtained from medical records. All 14 deaf horses had loss of all BAER waveforms consistent with complete deafness. Most horses had the splashed white or splashed white-frame blend coat pattern. Other patterns included frame overo and tovero. All of the deaf horses had extensive head and limb white markings, although the amount of white on the neck and trunk varied widely. All horses had at least 1 partially heterochromic iris, and most had 2 blue eyes. Ninety-one percent (31/34) of deaf and suspected-deaf horses had the EDNBR gene mutation. Deaf and suspected-deaf horses were used successfully for various performance events. All nondeaf horses had unremarkable BAER results. Veterinarians should be aware of deafness among American Paint Horses, particularly those with a splashed white or frame overo coat color pattern, blend of these patterns, or tovero pattern. Horses with extensive head and limb markings and those with blue eyes appeared to be at particular risk.

  2. Piracetam-induced changes on the brainstem auditory response in anesthetized juvenile rhesus monkeys (Macaca mulatta). Report of two clinical cases.

    Science.gov (United States)

    Durand-Rivera, A; Gonzalez-Pina, R; Hernandez-Godinez, B; Ibanez-Contreras, A; Bueno-Nava, A; Alfaro-Rodriguez, A

    2012-10-01

    We describe two clinical cases and examine the effects of piracetam on the brainstem auditory response in infantile female rhesus monkeys (Macaca mulatta). We found that the interwave intervals show a greater reduction in a 3-year-old rhesus monkey compared to a 1-year-old rhesus monkey. In this report, we discuss the significance of these observations. © 2012 John Wiley & Sons A/S.

  3. Comparison of noise-induced changes of auditory brainstem and middle latency response amplitudes in rats

    Czech Academy of Sciences Publication Activity Database

    Popelář, Jiří; Grécová, Jolana; Rybalko, Natalia; Syka, Josef

    2008-01-01

    Roč. 245, 1-2 (2008), s. 82-91 ISSN 0378-5955 R&D Projects: GA ČR GA309/07/1336; GA MZd NR8113; GA MŠk(CZ) LC554 Institutional research plan: CEZ:AV0Z50390512 Keywords : Noise exposure * Long evans rats * Middle latency responses Subject RIV: FH - Neurology Impact factor: 2.333, year: 2008

  4. Achado ocasional de doenças neurológicas durante a pesquisa da surdez infantil através do BERA Occasional finding of neurological disorders during children hearing loss evaluation using the ABR

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Alves de Sousa

    2007-06-01

    Full Text Available Uma das mais importantes aplicações clínicas dos potenciais evocados auditivos de tronco cerebral (BERA é a sua utilização na avaliação da surdez infantil. Atualmente o BERA também é utilizado na triagem das síndromes cócleo-vestibulares a procura de lesões retro-cocleares, na monitoração dos estados de coma (morte cerebral, na monitoração do tronco cerebral em cirurgias da base do crânio, etc. Uma das qualidades do BERA é a sua capacidade de avaliar a integridade neurofisiológica das vias auditivas do tronco cerebral. Desta maneira, algumas vezes durante a pesquisa dos limiares auditivos infantis, nos deparamos com BERAs que sugerem a presença de lesões retro-cocleares das vias auditivas (assimetria de traçados, aumento dos intervalos interpicos, muitas vezes comprovadas através de exames de imagem. Trata-se de achado ocasional de moléstia neurológica por ocasião da pesquisa dos limiares auditivos infantis. Neste trabalho relataremos dois casos de doenças neurológicas, diagnosticadas ocasionalmente através do BERA realizado com o intuito de se pesquisar os limiares auditivos.One of the most important applications of the Brainstem evoked response audiometry (ABR is in the evaluation of hearing loss in children. Today the ABR is also indicated in the screening of cochleo-vestibular syndromes to detect retrocochlear lesions, to monitor patients in a coma (brain death, in monitoring the brainstem during skull base surgery, etc. Among the many BERA qualities, is its capacity to evaluate the neurophysiologic integrity of the auditory brainstem pathway. In doing so, sometimes while evaluating hearing function in children we are faced with ABR waves that suggest the presence of retrocochlear lesions (trace asymmetry, increased interpeak intervals, many times confirmed through image studies. These cases are seen as occasional findings of neurologic disorders during children hearing loss evaluation. In this study we report 2

  5. Adaptations in responsiveness of brainstem pain-modulating neurons in acute compared to chronic inflammation

    Science.gov (United States)

    Cleary, Daniel R.; Heinricher, Mary M.

    2013-01-01

    Despite similar behavioral hypersensitivity, acute and chronic pain have distinct neural bases. Here we used intraplantar injection of Complete Freund’s Adjuvant (CFA) to directly compare activity of pain-modulating neurons in the rostral ventromedial medulla (RVM) in acute versus chronic inflammation. Heat- and von Frey-evoked withdrawal reflexes and corresponding RVM neuronal activity were recorded in lightly anesthetized animals either during the first hour after CFA injection (acute) or 3–10 days later (chronic). Thermal and modest mechanical hyperalgesia during acute inflammation were associated with increases in the spontaneous activity of pain-facilitating ON-cells and suppression of pain-inhibiting OFF-cells. Acute hyperalgesia was reversed by RVM block, showing that the increased activity of RVM ON-cells is necessary for acute behavioral hypersensitivity. In chronic inflammation, thermal hyperalgesia had resolved, but mechanical hyperalgesia had become pronounced. The spontaneous discharges of ON- and OFF-cells were not different from controls, but the mechanical response thresholds for both cell classes were reduced into the innocuous range. RVM block in the chronic condition worsened mechanical hyperalgesia. These studies identify distinct contributions of RVM ON- and OFF-cells to acute and chronic inflammatory hyperalgesia. During early immune-mediated inflammation, ON-cell spontaneous activity promotes hyperalgesia. After inflammation is established, the anti-nociceptive influence of OFF-cells is dominant, yet the lowered threshold for the OFF-cell pause allows behavioral responses to stimuli that would normally be considered innocuous. The efficacy of OFF-cells in counteracting sensitization of ascending transmission pathways could therefore be an important determining factor in development of chronic inflammatory pain. PMID:23588008

  6. Adaptations in responsiveness of brainstem pain-modulating neurons in acute compared with chronic inflammation.

    Science.gov (United States)

    Cleary, Daniel R; Heinricher, Mary M

    2013-06-01

    Despite similar behavioral hypersensitivity, acute and chronic pain have distinct neural bases. We used intraplantar injection of complete Freund's adjuvant to directly compare activity of pain-modulating neurons in the rostral ventromedial medulla (RVM) in acute vs chronic inflammation. Heat-evoked and von Frey-evoked withdrawal reflexes and corresponding RVM neuronal activity were recorded in lightly anesthetized animals either during the first hour after complete Freund's adjuvant injection (acute) or 3 to 10 days later (chronic). Thermal and modest mechanical hyperalgesia during acute inflammation were associated with increases in the spontaneous activity of pain-facilitating ON-cells and suppression of pain-inhibiting OFF-cells. Acute hyperalgesia was reversed by RVM block, showing that the increased activity of RVM ON-cells is necessary for acute behavioral hypersensitivity. In chronic inflammation, thermal hyperalgesia had resolved but mechanical hyperalgesia had become pronounced. The spontaneous discharges of ON- and OFF-cells were not different from those in control subjects, but the mechanical response thresholds for both cell classes were reduced into the innocuous range. RVM block in the chronic condition worsened mechanical hyperalgesia. These studies identify distinct contributions of RVM ON- and OFF-cells to acute and chronic inflammatory hyperalgesia. During early immune-mediated inflammation, ON-cell spontaneous activity promotes hyperalgesia. After inflammation is established, the antinociceptive influence of OFF-cells is dominant, yet the lowered threshold for the OFF-cell pause allows behavioral responses to stimuli that would normally be considered innocuous. The efficacy of OFF-cells in counteracting sensitization of ascending transmission pathways could therefore be an important determining factor in development of chronic inflammatory pain. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All

  7. Conventional and cross-correlation brain-stem auditory evoked responses in the white leghorn chick: rate manipulations

    Science.gov (United States)

    Burkard, R.; Jones, S.; Jones, T.

    1994-01-01

    Rate-dependent changes in the chick brain-stem auditory evoked response (BAER) using conventional averaging and a cross-correlation technique were investigated. Five 15- to 19-day-old white leghorn chicks were anesthetized with Chloropent. In each chick, the left ear was acoustically stimulated. Electrical pulses of 0.1-ms duration were shaped, attenuated, and passed through a current driver to an Etymotic ER-2 which was sealed in the ear canal. Electrical activity from stainless-steel electrodes was amplified, filtered (300-3000 Hz) and digitized at 20 kHz. Click levels included 70 and 90 dB peSPL. In each animal, conventional BAERs were obtained at rates ranging from 5 to 90 Hz. BAERs were also obtained using a cross-correlation technique involving pseudorandom pulse sequences called maximum length sequences (MLSs). The minimum time between pulses, called the minimum pulse interval (MPI), ranged from 0.5 to 6 ms. Two BAERs were obtained for each condition. Dependent variables included the latency and amplitude of the cochlear microphonic (CM), wave 2 and wave 3. BAERs were observed in all chicks, for all level by rate combinations for both conventional and MLS BAERs. There was no effect of click level or rate on the latency of the CM. The latency of waves 2 and 3 increased with decreasing click level and increasing rate. CM amplitude decreased with decreasing click level, but was not influenced by click rate for the 70 dB peSPL condition. For the 90 dB peSPL click, CM amplitude was uninfluenced by click rate for conventional averaging. For MLS BAERs, CM amplitude was similar to conventional averaging for longer MPIs.(ABSTRACT TRUNCATED AT 250 WORDS).

  8. Pinpointing brainstem mechanisms responsible for autonomic dysfunction in Rett syndrome: therapeutic perspectives for 5-HT1A agonists

    Directory of Open Access Journals (Sweden)

    Ana Paula Abdala

    2014-05-01

    Full Text Available Rett syndrome is a neurological disorder caused by loss of function of methyl-CpG-binding protein 2 (MeCP2. Reduced function of this ubiquitous transcriptional regulator has a devastating effect on the central nervous system. One of the most severe and life-threatening presentations of this syndrome is brainstem dysfunction, which results in autonomic disturbances such as breathing deficits, typified by episodes of breathing cessation intercalated with episodes of hyperventilation or irregular breathing. Defects in numerous neurotransmitter systems have been observed in Rett syndrome both in animal models and patients. Here we dedicate special attention to serotonin due to its role in promoting regular breathing, increasing vagal tone, regulating mood, alleviating Parkinsonian-like symptoms and potential for therapeutic translation. A promising new symptomatic strategy currently focuses on regulation of serotonergic function using highly selective serotonin type 1A (5-HT1A biased agonists. We address this newly emerging therapy for respiratory brainstem dysfunction and challenges for translation with a holistic perspective of Rett syndrome, considering potential mood and motor effects.

  9. Age and duration of inflammatory environment differentially affect the neuroimmune response and catecholaminergic neurons in the midbrain and brainstem.

    Science.gov (United States)

    Bardou, Isabelle; Kaercher, Roxanne M; Brothers, Holly M; Hopp, Sarah C; Royer, Sarah; Wenk, Gary L

    2014-05-01

    Neuroinflammation and degeneration of ascending catecholaminergic systems occur early in the neurodegenerative process. Age and the duration of a pro-inflammatory environment induced by continuous intraventricular lipopolysaccharide (LPS) differentially affect the expression profile of pro- and anti-inflammatory genes and proteins as well as the number of activated microglia (express major histocompatibility complex II; MHC II) and the integrity and density of ascending catecholaminergic neural systems originating from the locus coeruleus (LC) and substantia nigra pars compacta (SNpc) in rats. LPS infusion increased gene expression and/or protein levels for both pro- and anti-inflammatory biomarkers. Although LPS infusion stimulated a robust increase in IL-1ß gene and protein expression, this increase was blunted with age. LPS infusion also increased the density of activated microglia cells throughout the midbrain and brainstem. Corresponding to the development of a pro-inflammatory environment, LC and SNpc neurons immunopositive for tyrosine-hydroxylase (the rate-limiting synthetic enzyme for dopamine and norepinephrine) decreased in number, along with a decrease in tyrosine-hydroxylase gene expression in the midbrain and/or brainstem region. Our data support the concept that continuous exposure to a pro-inflammatory environment drives exaggerated changes in the production and release of inflammatory mediators that interact with age to impair functional capacity of the SNpc and LC. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Pinpointing brainstem mechanisms responsible for autonomic dysfunction in Rett syndrome: therapeutic perspectives for 5-HT1A agonists

    Science.gov (United States)

    Abdala, Ana P.; Bissonnette, John M.; Newman-Tancredi, Adrian

    2014-01-01

    Rett syndrome is a neurological disorder caused by loss of function of methyl-CpG-binding protein 2 (MeCP2). Reduced function of this ubiquitous transcriptional regulator has a devastating effect on the central nervous system. One of the most severe and life-threatening presentations of this syndrome is brainstem dysfunction, which results in autonomic disturbances such as breathing deficits, typified by episodes of breathing cessation intercalated with episodes of hyperventilation or irregular breathing. Defects in numerous neurotransmitter systems have been observed in Rett syndrome both in animal models and patients. Here we dedicate special attention to serotonin due to its role in promoting regular breathing, increasing vagal tone, regulating mood, alleviating Parkinsonian-like symptoms and potential for therapeutic translation. A promising new symptomatic strategy currently focuses on regulation of serotonergic function using highly selective serotonin type 1A (5-HT1A) “biased agonists.” We address this newly emerging therapy for respiratory brainstem dysfunction and challenges for translation with a holistic perspective of Rett syndrome, considering potential mood and motor effects. PMID:24910619

  11. Three young adult patients with Pelizaeus-Merzbacher disease who showed only waves I and II in auditory brainstem responses but had good auditory perception.

    Science.gov (United States)

    Kaga, Kimitaka; Tamai, Fumi; Kodama, Mariko; Kodama, Kazuo

    2005-09-01

    Three young adult males with Pelizaeus-Merzbacher disease have been followed up since childhood. This disease is thought to be a dysmyelinating disorder of the brain during the prenatal period caused by gene mutations. The patients manifested horizontal nystagmus and severe rigidity of the extremities. Although the patients showed only waves I and II in auditory brainstem responses, they had relatively good hearing ability at approximately equal to dB. They could not speak words at all but could hear well and enjoy listening to conversation and music. One of them had a normal hearing threshold in pure-tone audiometry and a normal speech discrimination rate in speech audiometry. This can be explained by a nerve conduction blockade through dysmyelinated axons or the desynchronization of neurons and nerves responsible for the waves following waves I and II. At present, all three patients are living with their families. We report their present hearing, speech and language abilities.

  12. Brainstem Cavernous Angioma

    Science.gov (United States)

    ... surgical resection of cavernous angiomas, as they provide functional drainage. [5] Elimination of these anomalies can result ... from the brainstem; however, the potential for significant functional deficits from surgical complications is still significant. This ...

  13. Processing Complex Sounds Passing through the Rostral Brainstem: The New Early Filter Model

    Science.gov (United States)

    Marsh, John E.; Campbell, Tom A.

    2016-01-01

    The rostral brainstem receives both “bottom-up” input from the ascending auditory system and “top-down” descending corticofugal connections. Speech information passing through the inferior colliculus of elderly listeners reflects the periodicity envelope of a speech syllable. This information arguably also reflects a composite of temporal-fine-structure (TFS) information from the higher frequency vowel harmonics of that repeated syllable. The amplitude of those higher frequency harmonics, bearing even higher frequency TFS information, correlates positively with the word recognition ability of elderly listeners under reverberatory conditions. Also relevant is that working memory capacity (WMC), which is subject to age-related decline, constrains the processing of sounds at the level of the brainstem. Turning to the effects of a visually presented sensory or memory load on auditory processes, there is a load-dependent reduction of that processing, as manifest in the auditory brainstem responses (ABR) evoked by to-be-ignored clicks. Wave V decreases in amplitude with increases in the visually presented memory load. A visually presented sensory load also produces a load-dependent reduction of a slightly different sort: The sensory load of visually presented information limits the disruptive effects of background sound upon working memory performance. A new early filter model is thus advanced whereby systems within the frontal lobe (affected by sensory or memory load) cholinergically influence top-down corticofugal connections. Those corticofugal connections constrain the processing of complex sounds such as speech at the level of the brainstem. Selective attention thereby limits the distracting effects of background sound entering the higher auditory system via the inferior colliculus. Processing TFS in the brainstem relates to perception of speech under adverse conditions. Attentional selectivity is crucial when the signal heard is degraded or masked: e

  14. Atypical brainstem representation of onset and formant structure of speech sounds in children with language-based learning problems.

    Science.gov (United States)

    Wible, Brad; Nicol, Trent; Kraus, Nina

    2004-11-01

    This study investigated how the human auditory brainstem represents constituent elements of speech sounds differently in children with language-based learning problems (LP, n = 9) compared to normal children (NL, n = 11), especially under stress of rapid stimulation. Children were chosen for this study based on performance on measures of reading and spelling and measures of syllable discrimination. In response to the onset of the speech sound /da/, wave V-V(n) of the auditory brainstem response (ABR) had a significantly shallower slope in LP children, suggesting longer duration and/or smaller amplitude. The amplitude of the frequency following response (FFR) was diminished in LP subjects over the 229-686 Hz range, which corresponds to the first formant of the/da/ stimulus, while activity at 114 Hz, representing the fundamental frequency of /da/, was no different between groups. Normal indicators of auditory peripheral integrity suggest a central, neural origin of these differences. These data suggest that poor representation of crucial components of speech sounds could contribute to difficulties with higher-level language processes.

  15. Biological Imaging Capability in the ABRS Facility on ISS

    Science.gov (United States)

    Cox, David R.; Murdoch, T.; Regan, M. F.; Meshlberger, R. J.; Mortenson, T. E.; Albino, S. A.; Paul, A. L.; Ferl, R. J.

    2010-01-01

    This slide presentation reviews the Advanced Biological Research System (ABRS) on the International Space Station (ISS) and its biological imaging capability. The ABRS is an environmental control chamber. It has two indpendently controlled Experiment Research Chambers (ERCs) with temperature, relative humidity and carbon dioxide controls. ABRS is a third generation plant growth system. Several experiments are reviewed, with particular interest in the use of Green Fluorescent Protein (GFP) a non-destructive plant stress reporting mechanism, naturally found in jellyfish.

  16. Nuclear magnetic resonance imaging of the brainstem

    International Nuclear Information System (INIS)

    Kojima, Shigeyuki; Yagishita, Toshiyuki; Hirayama, Keizo; Arimizu, Noboru; Ikehira, Hiroo; Fukuda, Nobuo; Tateno, Yukio.

    1986-01-01

    NMR imaging of the brainstem region from 12 asymptomatic individuals were reviewed in addition to these of 12 patients with various symptoms of small brainstem lesions. Abnormalities consisted of 3 cases of multiple sclerosis, 1 case of neuro-Behcet disease, 5 cases of infarction and hematoma and 3 cases of degenerative disease. NMR transverse imaging using inversion recovery sequence was able to locate many of the normal intra-axial brainstem nuclei, the red nucleus, the substantia nigra, the pontine nuclei, the pontine reticular nuclei, the facial nerve nucleus and so on in an about half of 12 asymptomatic individuals. The remarkable gray-white matter differentiation was obtained on NMR imaging using inversion recovery sequence and enabled the internal structures to be visualized within the brainstem. In addition, the midsagittal imaging provided an excellent demonstration of anatomical relationships of the brainstem and surrounding structures. In the diencephalic region, the mamillary body, the anterior commissure and the optic chiasma were also demonstrated on the midsagittal imaging. The lesions within the brainstem were vaguely shown on X-ray computed tomography in 6 of 12 patients but NMR imaging using inversion recovery or spin echo sequence provided more detailed data and revealed clear small lesions, such as the demyelinated plaques of multiple sclerosis and lacunar infarcts in 9 of 12 patients. Especially, in 2 of 3 multiple sclerosis patients, the plaques of the brainstem were definitely identified on NMR imaging only and the accurate localized lesion which was responsible for the facial myokymia or the Foville syndrome was identified. These studies results show that on NMR imaging using several pulse sequences, it is possible to examine the atrophic or hypertrophic findings of the brainstem internal structures and compare the localization of the lesions with clinical symptoms accurately. (J.P.N.)

  17. Time-Dependent Compensatory Responses to Chronic Neuroinflammation in Hippocampus and Brainstem: The Potential Role of Glutamate Neurotransmission.

    Science.gov (United States)

    Brothers, Holly M; Bardou, Isabelle; Hopp, Sarah C; Marchalant, Yannick; Kaercher, Roxanne M; Turner, Sarah M; Mitchem, Mollie R; Kigerl, Kristina; Wenk, Gary L

    2013-03-28

    Chronic neuroinflammation is characteristic of neurodegenerative diseases and is present during very early stages, yet significant pathology and behavioral deficits do not manifest until advanced age. We investigated the consequences of experimentally-induced chronic neuroinflammation within the hippocampus and brainstem of young (4 mo) F-344 rats. Lipopolysaccharide (LPS) was infused continuously into the IV th ventricle for 2, 4 or 8 weeks. The number of MHC II immunoreactive microglia in the brain continued to increase throughout the infusion period. In contrast, performance in the Morris water maze was impaired after 4 weeks but recovered by 8 weeks. Likewise, a transient loss of tyrosine hydroxylase immunoreactivity in the substantia nigra and locus coeruleus was observed after 2 weeks, but returned to control levels by 4 weeks of continuous LPS infusion. These data suggest that direct activation of microglia is sufficient to drive, but not sustain, spatial memory impairment and a decrease in tyrosine hydroxylase production in young rats. Our previous studies suggest that chronic neuroinflammation elevates extracellular glutamate and that this elevation underlies the spatial memory impairment. In the current study, increased levels of GLT1 and SNAP25 in the hippocampus corresponded with the resolution of performance deficit. Increased expression of SNAP25 is consistent with reduced glutamate release from axonal terminals while increased GLT1 is consistent with enhanced clearance of extracellular glutamate. These data demonstrate the capacity of the brain to compensate for the presence of chronic neuroinflammation, despite continued activation of microglia, through changes in the regulation of the glutamatergic system.

  18. Abréviations et avertissements

    OpenAIRE

    2015-01-01

    Abréviations Références : B. Bartsch Bel. Bellin Bologne Expo. Bologne, 1988 B. S. Byam Shaw D. Duchesne D. L. David Landau Dut. Dutuit H. I et H. V Hind, tomes I et V H. H. Hind (Nielles) K. O. Expo. Paris, 1993, Konrad Oberhuber L. Levenson Lip. Lippmann Mantegna Expo. Londres, 1992 P. Passavant M. et R. Muraro et Rosand. Expo. Venise, 1976 R. R. Roger Rearick. Expo Paris, 1993 S. B. Suzanne Boorsch T. Tietze et Tietze-Conrat TIB. The Illustrated Bartsch Washington Expo. Washington, 1973 Ye...

  19. ABR-based newborn hearing screening with MB11 BERAphone® using an optimized chirp for acoustical stimulation.

    Science.gov (United States)

    Cebulla, Mario; Shehata-Dieler, Wafaa

    2012-04-01

    At our center, the Maico MB11 BERAphone(®) device is used for newborn hearing screening based on Auditory Brainstem Responses (ABR). In 2006, an optimized chirp stimulus was implemented in the device to increase the reliability and quality of the screening method. In 2002, an automated response detection algorithm had been implemented. This study analyzes the screening results using the MB11 BERAphone(®) device with the implemented chirp stimulus and automated response detection method. The data presented were collected in the well-baby nursery as part of the newborn hearing screening program following a two stage screening protocol. To focus the study on the typical routine screening, data from at-risk babies were not included. Overall, data from 6866 babies (3604 males and 3262 females) screened from March 2006 to April 2011 were analyzed in this study. Out of the 6866 babies screened, 6607 passed bilaterally prior to hospital discharge (defined as 1st stage in this hearing screening program). Therefore, the pre-discharge pass rate of the hearing screening with the MB11 BERAphone(®) device was 96.2%. The resulting referral rate was 3.8%. The median test time per ear (excluding time for preparation and data reporting) was 28s with a range of 15-112s (5-95th percentile). The number of infants referred for 2nd stage, post-discharge re-screening was 259. Of this group, 71 passed bilaterally and 188 failed the re-screening in one or both ears. Therefore, including both the pre-discharge and post-discharge screening results, the bilateral pass rate was 97.3% and 2.7% were referred for diagnostic evaluation. Diagnostic testing was performed on all of the 188 infants who were referred. Results showed that 47 of these babies had hearing loss. This equates to a positive predictive value for a refer result of 25%. The observed prevalence of hearing impairment in our population was 0.684%. Diagnostic results for 141 of the referred newborns proved that they had normal

  20. The anaerobic baffled reactor (ABR): An appropriate technology for ...

    African Journals Online (AJOL)

    This project has studied the appropriateness of the ABR for on-site primary sanitation in low-income communities. The baffled design of the ABR ensures high solids retention resulting in high treatment rates, while the overall sludge production is characteristically low. Effluent COD values measured from a 3 000 l pilot ABR ...

  1. Aplicação da audiometria troncoencefálica na detecção de perdas auditivas retrococleares em trabalhadores de manutenção hospitalar expostos a ruído Auditory brainstem responses evaluation of retrocochlear disease in workers from a general hospital exposed to noise

    Directory of Open Access Journals (Sweden)

    Victor Luiz da Silveira

    2011-02-01

    Full Text Available O objetivo principal deste estudo seccional foi averiguar a presença de comprometimento auditivo retrococlear num grupo de trabalhadores de manutenção de um hospital de grande porte com histórico de exposição a ruído. Foram avaliados 31 trabalhadores de três setores da divisão de engenharia entre 25 e 60 anos e com exposição contínua a ruído entre 2 e 45 anos. O processo avaliativo contou com triagem audiométrica ocupacional e audiometria troncoencefálica (ATE. Foram detectadas anormalidades na ATE em sete pacientes (22,6%, caracterizadas por aumento de latências de ondas III (14,3% e V (28,6%; prolongamento dos interpicos I-III (71,4%, III-V (28,6% e I-V (85,7%. Das 35 orelhas com audição normal (três unilateralmente e 32 bilateralmente, quatro (11,4% apresentaram comprometimento retrococlear. A alta prevalência de comprometimento retrococlear no grupo induz supor que tal distúrbio seja mais frequente que o encontrado e esteja sendo subestimado na investigação diagnóstica desses trabalhadores. A ocorrência desses resultados sem a presença de alterações audiométricas sugere que a ATE seja mais sensível que a audiometria tonal na investigação de perda auditiva provocada por ruído, por isso sua utilização deva ser incentivada.The main purpose of this cross-seccional study was to investigate the presence of retrocochlear disease in a group of maintenance workers from a general hospital, who presents a history of noise exposure. Thirty one workers of three engineering sections with age range from 25 to 60 years and continuous noise exposure from 2 and 45 years, were examined. The evaluation included an audiometric occupational selection and auditory brainstem responses (ABR. ABR abnormalities were detected in seven patients (22.6% and it was found latency increase of waves III (14.3% and V (28.6%, and interpeak prolongation I-III (71.4%, III-V (28.6% and I-V (85.7%. Among 35 ears with normal audition right, left or

  2. Pediatric brainstem oligodendroglioma

    Directory of Open Access Journals (Sweden)

    Sandeep Mohindra

    2012-01-01

    Full Text Available The authors present the first report of pediatric brainstem oligodendroglioma, infiltrating midbrain, and medulla oblongata. The report details clinical features, radiological findings, and surgical steps. As this entity is exceedingly uncommon, the overall epidemiology, prognosis, and long-term outcome remain far from established.

  3. Effect of neonatal asphyxia on the impairment of the auditory pathway by recording auditory brainstem responses in newborn piglets: a new experimentation model to study the perinatal hypoxic-ischemic damage on the auditory system.

    Directory of Open Access Journals (Sweden)

    Francisco Jose Alvarez

    Full Text Available Hypoxia-ischemia (HI is a major perinatal problem that results in severe damage to the brain impairing the normal development of the auditory system. The purpose of the present study is to study the effect of perinatal asphyxia on the auditory pathway by recording auditory brain responses in a novel animal experimentation model in newborn piglets.Hypoxia-ischemia was induced to 1.3 day-old piglets by clamping 30 minutes both carotid arteries by vascular occluders and lowering the fraction of inspired oxygen. We compared the Auditory Brain Responses (ABRs of newborn piglets exposed to acute hypoxia/ischemia (n = 6 and a control group with no such exposure (n = 10. ABRs were recorded for both ears before the start of the experiment (baseline, after 30 minutes of HI injury, and every 30 minutes during 6 h after the HI injury.Auditory brain responses were altered during the hypoxic-ischemic insult but recovered 30-60 minutes later. Hypoxia/ischemia seemed to induce auditory functional damage by increasing I-V latencies and decreasing wave I, III and V amplitudes, although differences were not significant.The described experimental model of hypoxia-ischemia in newborn piglets may be useful for studying the effect of perinatal asphyxia on the impairment of the auditory pathway.

  4. Effect of neonatal asphyxia on the impairment of the auditory pathway by recording auditory brainstem responses in newborn piglets: a new experimentation model to study the perinatal hypoxic-ischemic damage on the auditory system.

    Science.gov (United States)

    Alvarez, Francisco Jose; Revuelta, Miren; Santaolalla, Francisco; Alvarez, Antonia; Lafuente, Hector; Arteaga, Olatz; Alonso-Alconada, Daniel; Sanchez-del-Rey, Ana; Hilario, Enrique; Martinez-Ibargüen, Agustin

    2015-01-01

    Hypoxia-ischemia (HI) is a major perinatal problem that results in severe damage to the brain impairing the normal development of the auditory system. The purpose of the present study is to study the effect of perinatal asphyxia on the auditory pathway by recording auditory brain responses in a novel animal experimentation model in newborn piglets. Hypoxia-ischemia was induced to 1.3 day-old piglets by clamping 30 minutes both carotid arteries by vascular occluders and lowering the fraction of inspired oxygen. We compared the Auditory Brain Responses (ABRs) of newborn piglets exposed to acute hypoxia/ischemia (n = 6) and a control group with no such exposure (n = 10). ABRs were recorded for both ears before the start of the experiment (baseline), after 30 minutes of HI injury, and every 30 minutes during 6 h after the HI injury. Auditory brain responses were altered during the hypoxic-ischemic insult but recovered 30-60 minutes later. Hypoxia/ischemia seemed to induce auditory functional damage by increasing I-V latencies and decreasing wave I, III and V amplitudes, although differences were not significant. The described experimental model of hypoxia-ischemia in newborn piglets may be useful for studying the effect of perinatal asphyxia on the impairment of the auditory pathway.

  5. The dominant role of inhibition in creating response selectivities for communication calls in the brainstem auditory system.

    Science.gov (United States)

    Pollak, George D

    2013-11-01

    This review is concerned with how communication calls are processed and represented by populations of neurons in both the inferior colliculus (IC), the auditory midbrain nucleus, and the dorsal nucleus of the lateral lemniscus (DNLL), the nucleus just caudal to the IC. The review has five sections where focus in each section is on inhibition and its role in shaping response selectivity for communication calls. In the first section, the lack of response selectivity for calls in DNLL neurons is presented and discusses why inhibition plays virtually no role in shaping selectivity. In the second section, the lack of selectivity in the DNLL is contrasted with the high degree of response selectivity in the IC. The third section then reviews how inhibition in the IC shapes response selectivities for calls, and how those selectivities can create a population response with a distinctive response profile to a particular call, which differs from the population profile evoked by any other call. The fourth section is concerned with the specifics of inhibition in the IC, and how the interaction of excitation and inhibition creates directional selectivities for frequency modulations, one of the principal acoustic features of communication signals. The two major hypotheses for directional selectivity are presented. One is the timing hypothesis, which holds that the precise timing of excitation relative to inhibition is the feature that shapes directionality. The other hypothesis is that the relative magnitudes of excitation and inhibition are the dominant features that shape directionality, where timing is relatively unimportant. The final section then turns to the role of serotonin, a neuromodulator that can markedly change responses to calls in the IC. Serotonin provides a linkage between behavioral states and processing. This linkage is discussed in the final section together with the hypothesis that serotonin acts to enhances the contrast in the population responses to various

  6. A pivotal role for enhanced brainstem Orexin receptor 1 signaling in the central cannabinoid receptor 1-mediated pressor response in conscious rats.

    Science.gov (United States)

    Ibrahim, Badr Mostafa; Abdel-Rahman, Abdel A

    2015-10-05

    Orexin receptor 1 (OX1R) signaling is implicated in cannabinoid receptor 1 (CB1R) modulation of feeding. Further, our studies established the dependence of the central CB1R-mediated pressor response on neuronal nitric oxide synthase (nNOS) and extracellular signal-regulated kinase1/2 (ERK1/2) phosphorylation in the RVLM. Here, we tested the novel hypothesis that brainstem orexin-A/OX1R signaling plays a pivotal role in the central CB1R-mediated pressor response. Our multiple labeling immunofluorescence findings revealed co-localization of CB1R, OX1R and the peptide orexin-A within the C1 area of the rostral ventrolateral medulla (RVLM). Activation of central CB1R following intracisternal (i.c.) WIN55,212-2 (15μg/rat) in conscious rats caused significant increases in BP and orexin-A level in RVLM neuronal tissue. Additional studies established a causal role for orexin-A in the central CB1R-mediated pressor response because (i) selective blockade of central CB1R (AM251, 30μg/rat; i.c.) abrogated WIN55,212-2-evoked increases in RVLM orexin-A level, (ii) the selective OX1R antagonist SB-408124 (10nmol/rat; i.c.) attenuated orexin-A (3nmol/rat; i.c.) or WIN55,212-2 (15μg/rat; i.c.)-evoked pressor response while selective CB1R blockade (AM251) had no effect on orexin-A (3nmol/rat; i.c.)-evoked pressor response, (iii) direct CB1R activation in the RVLM (WIN55,212-2; 0.1μg/rat) increased RVLM orexin-A and BP. Finally, SB-408124 attenuated WIN55,212-2-evoked increases in RVLM nNOS and ERK1/2 phosphorylation and BP. Our findings suggest that orexin-A/OX1R dependent activation of the RVLM nNOS/ERK1/2 cascade is essential neurochemical mechanism for the central CB1R-mediated pressor response in conscious rats. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Brainstem Tuberculoma in Pregnancy

    Directory of Open Access Journals (Sweden)

    Dana A. Muin

    2015-01-01

    Full Text Available We report a case of a Somali refugee who presented in the second trimester of her first pregnancy with a four-week history of gradual right-sided sensomotoric hemisyndrome including facial palsy and left-sided paresis of the oculomotorius nerve causing drooping of the left eyelid and double vision. Cranial magnetic resonance imaging revealed a solitary brainstem lesion. Upon detection of hilar lymphadenopathy on chest X-ray (CXR, the diagnosis of disseminated tuberculosis with involvement of the central nervous system was confirmed by PCR and treatment induced with rifampicin, isoniazid, pyrazinamide, and ethambutol. The patient had a steady neurological improvement and a favorable pregnancy outcome.

  8. Comparison of Auditory Brainstem Response in HIV-1 exposed and unexposed newborns and their correlation with the maternal viral load and CD4 cell counts

    Science.gov (United States)

    FASUNLA, Ayotunde James; OGUNBOSI, Babatunde Oluwatosin; ODAIBO, Georgina Njideka; NWAORGU, Onyekwere George Benjamin; TAIWO, Babafemi; OLALEYE, David Olufemi; OSINUSI, Kikelomo; MURPHY, Robert Leo; ADEWOLE, Isaac Folorunso; AKINYINKA, Olusegun Olusina

    2014-01-01

    Objective The effects of maternal HIV infection and antiretroviral therapy on hearing of HIV-exposed newborns in sub-Saharan Africa have not been investigated. We determined the prevalence of sensorineural hearing loss among HIV-exposed newborns and the association between the hearing threshold and maternal & newborn parameters. Design A cohort audiometric study of newborns between October 2012 and April 2013. Settings Secondary and tertiary hospital based study. Participants Consecutive 126 HIV-exposed and 121 HIV-unexposed newborns. Intervention Hearing screening of the newborns were done with Auditory Brainstem Response and compared with maternal HAART, CD4 cell counts, RNA viral loads and newborn CD4 percent. Main outcome measure Hearing threshold levels of both groups were measured and analyzed. Results 11.1% of HIV-exposed and 6.6% of unexposed newborns had hearing impairment (p=0.2214). 6.4% of HIV-exposed and 2.5% HIV-unexposed newborns had hearing threshold >20dBHL (p = 0.1578). There was no significant association between the hearing thresholds of HIV-exposed newborns and maternal CD4 cell counts (p = 0.059) but there was with maternal viral load (p=0.034). There was significant difference between the hearing thresholds of HIV-exposed newborns with CD4 % of ≤25 and >25. This study showed significant difference in the hearing of the 119 HAART-exposed newborns and 7 unexposed newborns (p=0.002; RR=0.13 [0.05–0.32]). Conclusion There was a trend towards more hearing loss in HIV-exposed newborns. However, hearing thresholds increase with increasing mothers’ viral load. This background information supports the need for further studies on the role of in-utero exposure to HIV and HAART in newborn hearing loss. PMID:25313584

  9. Congenital brainstem disconnection associated with a syrinx of the brainstem

    NARCIS (Netherlands)

    Barth, P. G.; de Vries, L. S.; Nikkels, P. G. J.; Troost, D.

    We report a case of congenital brainstem disconnection including the second detailed autopsy. A full-term newborn presented with irreversible apnoea and died on the fifth day. MRI revealed disconnection of the brainstem. The autopsy included a series of transverse sections of the mesencephalon,

  10. Congenital brainstem disconnection associated with a syrinx of the brainstem

    NARCIS (Netherlands)

    Barth, P. G.; de Vries, L. S.; Nikkels, P. G. J.; Troost, D.

    2008-01-01

    We report a case of congenital brainstem disconnection including the second detailed autopsy. A full-term newborn presented with irreversible apnoea and died on the fifth day. MRI revealed disconnection of the brainstem. The autopsy included a series of transverse sections of the mesencephalon,

  11. MR findings of brainstem injury

    Energy Technology Data Exchange (ETDEWEB)

    Park, Man Soo; Hwang, Woo Cheol; Park, Choong Ki [Hallym University College of Medicine, Seoul (Korea, Republic of); Suh, Dae Chul [University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, Sang Joon [Dankook University of College of Medicine, Cheonan (Korea, Republic of)

    1995-02-15

    To analyze the characteristics of traumatic brainstem injury by CT and MR. CT and MR studies of 10 patients with traumatic brainstem lesion in MR were retrospectively reviewed, particularly attended to location, signal intensity and associated lesions. CT failed to depict 8 of 10 brainstem lesions. All lesions were detected in MR images with T2-weighted images showing higher detection rate (n = 10) (100%) than T1-weighted images (n = 3) (30%) or CT (n = 2) (20%). The brainstem lesions located in the dorsolateral aspects of the rostral brainstem (mid brain and upper pons) in 7 (70%) cases, in ventral aspects of rostral brain in 2 (20%) cases and in median portion of pons in 1 (10%) case. Corpus callosal (n = 5), lobar white matter (n = 5) diffuse axonal injury, and 2 hemorrhagic lesions in basal ganglia were the associated findings. MR imaging is more helpful than CT in the detection of brainstem injury, especially T2 weighted images. Primary brainstem lesions were typically located in the dorsolateral aspect of rostral brainstem (midbrain and upper pons). Corpus callosum and white matter lesions were frequently associated.

  12. Deficits in auditory brainstem pathway encoding of speech sounds in children with learning problems.

    Science.gov (United States)

    King, Cynthia; Warrier, Catherine M; Hayes, Erin; Kraus, Nina

    2002-02-15

    Auditory brainstem responses were recorded in normal children (NL) and children clinically diagnosed with a learning problem (LP). These responses were recorded to both a click stimulus and the formant transition portion of a speech syllable /da/. While no latency differences between the NL and LP populations were seen in responses to the click stimuli, the syllable /da/ did elicit latency differences between these two groups. Deficits in cortical processing of signals in noise were seen for those LP subjects with delayed brainstem responses to the /da/, but not for LPs with normal brainstem measures. Preliminary findings indicate that training may be beneficial to LP subjects with brainstem processing delays.

  13. Comparing statistics for objective detection of transient and steady-state evoked responses in newborns.

    Science.gov (United States)

    Mijares, Eleina; Pérez Abalo, María Cecilia; Herrera, Didiesdle; Lage, Agustin; Vega, Mayrim

    2013-01-01

    Receiver operating characteristic (ROC) methodology was used to compare the performance of different statistics in the automatic detection of multiple auditory steady-state responses (MSSR) and click auditory brainstem responses (cABR). Thirty-five healthy newborns tested within the first two weeks of birth. In each case cABR and MSSR (0.5 and 2 kHz) were recorded with and without acoustic stimulation, using AUDIX equipment. With this test sample of recordings, ROC curves were evaluated separately for each statistic evaluated: (1) the standard deviation ratio (SDR) and the correlation coefficient ratio (CCR) for the cABR; (2) the Hotelling T2 (HT2) and circular T2 (CT2) for the MSSR. All objective detection methods performed well (areas under ROC (AUC) > 0.9). The MSSR statistics showed significantly larger AUCs at both frequencies (HT2: 0.98 and 1; CT2: 0.96 and 0.99) than the cABR measures (SDR: 0.91 and CCR: 0.92). The HT2 hits rate was the highest (97-100% at 0.5 and 2 kHz) for fixed false alarms rates of both 10 and 20%. This superiority of performance of T2-like statistics, reflecting inherent advantages of MSSR analysis for automation, warrants serious consideration for further development of newborn screening technology.

  14. Cryptic vascular malformations involving the brainstem

    Energy Technology Data Exchange (ETDEWEB)

    Yeates, A.; Enzmann, D.

    1983-01-01

    Six patients with angiographically cryptic vascular malformations involving the brainstem were examined with computed tomography (CT). The clinical and CT findings of cryptic vascular malformations of the brainstem are described and distinguished from those of brainstem glioma and multiple sclerosis. Calcification within a brainstem lesion that displays relatively little mass effect and shows little contrast enhancement, particularly when associated with a long history of waxing and waning brainstem symptoms, should suggest a vascular malformation.

  15. Further characterization of the ABR gene in medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Wright-White, E.C.; Haken, M.S. von; McDonald J.D. [Univ. of Chicago, IL (United States)] [and others

    1994-09-01

    Although brain tumors are the most common type of solid cancer in children, little is known about their etiology at the molecular genetic level. Using a panel of 20 chromosome 17p markers, we have previously determined that loss of distal chromosome 17p DNA sequences occurs in 14 of 35 specimens (40%) of medulloblastoma, one of the most common pediatric intracranial neoplasms. Analysis of these same tumors using a PCR-denaturing gradient gel electrophoresis technique has shown only two p53 gene mutations. These results suggest that a tumor suppressor gene in addition to p53 may be located on distal chromosome 17p. Consensus deletion mapping of our specimens suggests that the smallest site of chromosomal loss in defined distally by marker 144-D6, the most telomeric probe as yet identified on chromosome 17p, and proximally by the ABR marker, a BCR homologous gene containing two highly polymorphic VNTR regions. We have used fluorescence in situ hybridization and pulsed-field gel electrophoresis to determine that the ABR gene lies transcriptionally oriented 5{prime} to 3{prime} at a distance of 240 kb from marker 144-D6. We have also constructed a cosmid contig map spanning 120 kb of this region. Using one of these cosmids as a probe, we have detected breakpoints in three of the tumor specimens that lie between the two VNTR regions within the ABR gene. We have subsequently designed PCR primers to cover the breakpoint region which include the ABR exons which have the strongest homology to the BCR gene (Mbcr region), and are screening our tumor specimens for mutations. These results suggest that loss of ABR gene sequences may be involved in the etiology of medulloblastoma.

  16. Alteration of glycine receptor immunoreactivity in the auditory brainstem of mice following three months of exposure to radiofrequency radiation at SAR 4.0 W/kg.

    Science.gov (United States)

    Maskey, Dhiraj; Kim, Hyung Gun; Suh, Myung-Whan; Roh, Gu Seob; Kim, Myeung Ju

    2014-08-01

    The increasing use of mobile communication has triggered an interest in its possible effects on the regulation of neurotransmitter signals. Due to the close proximity of mobile phones to hearing-related brain regions during usage, its use may lead to a decrease in the ability to segregate sounds, leading to serious auditory dysfunction caused by the prolonged exposure to radiofrequency (RF) radiation. The interplay among auditory processing, excitation and inhibitory molecule interactions plays a major role in auditory function. In particular, inhibitory molecules, such a glycine, are predominantly localized in the auditory brainstem. However, the effects of exposure to RF radiation on auditory function have not been reported to date. Thus, the aim of the present study was to investigate the effects of exposure to RF radiation on glycine receptor (GlyR) immunoreactivity (IR) in the auditory brainstem region at 835 MHz with a specific absorption rate of 4.0 W/kg for three months using free-floating immunohistochemistry. Compared with the sham control (SC) group, a significant loss of staining intensity of neuropils and cells in the different subdivisions of the auditory brainstem regions was observed in the mice exposed to RF radiation (E4 group). A decrease in the number of GlyR immunoreactive cells was also noted in the cochlear nuclear complex [anteroventral cochlear nucleus (AVCN), 31.09%; dorsal cochlear nucleus (DCN), 14.08%; posteroventral cochlear nucleus (PVCN), 32.79%] and the superior olivary complex (SOC) [lateral superior olivary nucleus (LSO), 36.85%; superior paraolivary nucleus (SPN), 24.33%, medial superior olivary nucleus (MSO), 23.23%; medial nucleus of the trapezoid body (MNTB), 10.15%] of the mice in the E4 group. Auditory brainstem response (ABR) analysis also revealed a significant threshold elevation of in the exposed (E4) group, which may be associated with auditory dysfunction. The present study suggests that the auditory brainstem region

  17. Methamphetamine-related brainstem haemorrhage.

    Science.gov (United States)

    Chiu, Zelia K; Bennett, Iwan E; Chan, Patrick; Rosenfeld, Jeffrey V

    2016-10-01

    We report the case of an otherwise healthy 29-year-old woman who presented with a brainstem haemorrhage following intravenous methamphetamine use. Extensive investigation did not reveal an underlying pathology, and the development of symptoms was temporally related to methamphetamine injection. Although intracerebral haemorrhage secondary to methamphetamine use is well documented, this report describes a haemorrhage within the brainstem which is a rare location. While animal studies have demonstrated the potential of methamphetamines to produce brainstem haemorrhages, there has only been one previous report describing a haemorrhage in this location due to amphetamine use in humans. We conclude with a brief discussion of the clinical features and aetiology of methamphetamine-related stroke. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Identification, occurrence, and validation of DRE and ABRE Cis-regulatory motifs in the promoter regions of genes of Arabidopsis thaliana.

    Science.gov (United States)

    Mishra, Sonal; Shukla, Aparna; Upadhyay, Swati; Sanchita; Sharma, Pooja; Singh, Seema; Phukan, Ujjal J; Meena, Abha; Khan, Feroz; Tripathi, Vineeta; Shukla, Rakesh Kumar; Shrama, Ashok

    2014-04-01

    Plants posses a complex co-regulatory network which helps them to elicit a response under diverse adverse conditions. We used an in silico approach to identify the genes with both DRE and ABRE motifs in their promoter regions in Arabidopsis thaliana. Our results showed that Arabidopsis contains a set of 2,052 genes with ABRE and DRE motifs in their promoter regions. Approximately 72% or more of the total predicted 2,052 genes had a gap distance of less than 400 bp between DRE and ABRE motifs. For positional orientation of the DRE and ABRE motifs, we found that the DR form (one in direct and the other one in reverse orientation) was more prevalent than other forms. These predicted 2,052 genes include 155 transcription factors. Using microarray data from The Arabidopsis Information Resource (TAIR) database, we present 44 transcription factors out of 155 which are upregulated by more than twofold in response to osmotic stress and ABA treatment. Fifty-one transcripts from the one predicted above were validated using semiquantitative expression analysis to support the microarray data in TAIR. Taken together, we report a set of genes containing both DRE and ABRE motifs in their promoter regions in A. thaliana, which can be useful to understand the role of ABA under osmotic stress condition. © 2013 Institute of Botany, Chinese Academy of Sciences.

  19. Direct surgery for brainstem lesions

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Noboru [Gifu Univ. (Japan). School of Medicine

    1997-09-01

    Direct surgery for intrinsic lesions of the brainstem has been considered a hazardous procedure. During the past 10 years, 32 cases of symptomatic lesions involving the brainstem were operated on. Magnetic resonance (MR) imaging is of greatest value in the diagnosis and for surgical indications. Almost all cases were treated by radical extirpation. Namely, 9 cavernous angiomas and 2 hemangioblastomas resulted in radical extirpation. The preoperative neurological deficits improved after surgery. Also, 2 ependymomas, 4 medulloblastomas, 4 plexus papillomas, and 1 epidermoid were successfully extirpated, and the surgical treatment for them allowed favorable outcome. Therefore, those brainstem lesions were considered to be more favorable indications for direct surgery. On the other hand, 4 astrocytomas and 6 glioblastomas were either subtotally or partially resected, in which a small incision in the fourth ventricle floor and the surface of the brainstem was made when the lesion was intramedullary. Consequently, there were neither mortality in surgery nor aggravation of the focal neurological symptoms. High-grade glioma in 6 cases was removed as much as possible, but almost all of the cases nevertheless expired due to prompt recurrence under 2 years after onset of symptoms and surgery. (author)

  20. Auditory brainstem's sensitivity to human voices.

    Science.gov (United States)

    Nan, Yun; Skoe, Erika; Nicol, Trent; Kraus, Nina

    2015-03-01

    Differentiating between voices is a basic social skill humans acquire early in life. The current study aimed to understand the subcortical mechanisms of voice processing by focusing on the two most important acoustical voice features: the fundamental frequency (F0) and harmonics. We measured frequency following responses in a group of young adults to a naturally produced speech syllable under two linguistic contexts: same-syllable and multiple-syllable. Compared to the same-syllable context, the multiple-syllable context contained more speech cues to aid voice processing. We analyzed the magnitude of the response to the F0 and harmonics between same-talker and multiple-talker conditions within each linguistic context. Results establish that the human auditory brainstem is sensitive to different talkers as shown by enhanced harmonic responses under the multiple-talker compared to the same-talker condition, when the stimulus stream contained multiple syllables. This study thus provides the first electrophysiological evidence of the auditory brainstem's sensitivity to human voices. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. SU-B-213-06: Development of ABR Examination Questions

    International Nuclear Information System (INIS)

    Allison, J.

    2015-01-01

    The North American medical physics community validates the education received by medical physicists and the clinical qualifications for medical physicists through accreditation of educational programs and certification of medical physicists. Medical physics educational programs (graduate education and residency education) are accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), whereas medical physicists are certified by several organizations, the most familiar of which is the American Board of Radiology (ABR). In order for an educational program to become accredited or a medical physicist to become certified, the applicant must meet certain specified standards set by the appropriate organization. In this Symposium, representatives from both CAMPEP and the ABR will describe the process by which standards are established as well as the process by which qualifications of candidates for accreditation or certification are shown to be compliant with these standards. The Symposium will conclude with a panel discussion. Learning Objectives: Recognize the difference between accreditation of an educational program and certification of an individual Identify the two organizations primarily responsible for these tasks Describe the development of educational standards Describe the process by which examination questions are developed GS is Executive Secretary of CAMPEP

  2. SU-B-213-05: Development of ABR Certification Standards

    International Nuclear Information System (INIS)

    Seibert, J.

    2015-01-01

    The North American medical physics community validates the education received by medical physicists and the clinical qualifications for medical physicists through accreditation of educational programs and certification of medical physicists. Medical physics educational programs (graduate education and residency education) are accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), whereas medical physicists are certified by several organizations, the most familiar of which is the American Board of Radiology (ABR). In order for an educational program to become accredited or a medical physicist to become certified, the applicant must meet certain specified standards set by the appropriate organization. In this Symposium, representatives from both CAMPEP and the ABR will describe the process by which standards are established as well as the process by which qualifications of candidates for accreditation or certification are shown to be compliant with these standards. The Symposium will conclude with a panel discussion. Learning Objectives: Recognize the difference between accreditation of an educational program and certification of an individual Identify the two organizations primarily responsible for these tasks Describe the development of educational standards Describe the process by which examination questions are developed GS is Executive Secretary of CAMPEP

  3. Contribuição do potencial evocado auditivo em pacientes com vertigem Results of brainstem evoked response in patients with vestibular complaints

    Directory of Open Access Journals (Sweden)

    Gisiane Munaro

    2010-06-01

    Full Text Available A avaliação otoneurológica consiste em exames para investigação de patologias auditivas e vestibulares, incluindo o potencial evocado de tronco encefálico e a vectoeletronistagmografia. OBJETIVO: Descrever os resultados da avaliação otoneurológica em pacientes com queixas vestibulococleares, normo-ouvintes e com perda auditiva, comparados a grupo-controle. MATERIAL E MÉTODOS: Estudo transversal, retrospectivo, observacional, realizado com 56 pacientes vertiginosos avaliados por audiometria, vectoeletronistagmografia e potencial evocado auditivo de tronco encefálico, divididos em grupo A, 31 pacientes normo-ouvintes, e grupo B, 25 pacientes com perda auditiva, comparados ao grupo-controle constituído por dez voluntários normo-ouvintes assintomáticos. RESULTADOS: Os pacientes dos grupos A e B apresentaram aumento em monobloco das latências absolutas das ondas I, III e V estatisticamente significante, quando comparados ao grupo-controle, embora com valores dentro da normalidade. A ausência da onda I a 80 dBNA foi um achado comum para ambos os grupos e ocorreu em quatro (12,9% sujeitos bilateralmente e em três (9,6% unilateralmente no grupo A e em oito (32% pacientes no grupo B bilateralmente. Nos dois casos em que a vectoeletronistagmografia acusou alteração vestibular central não ocorreram alterações nos parâmetros dos potenciais evocados. CONCLUSÃO: Os pacientes com vertigem, normo-ouvintes e com perda auditiva, apresentaram latências absolutas aumentadas quando comparados a grupo-controleOtoneurological evaluations are based on tests which investigate auditory and vestibular disorders, including brainstem evoked auditory potentials and vecto-electronystagmography. AIM: to describe the results from the otoneurological assessment of patients with vestibulocochlear complaints, normal hearing individuals and patients with hearing loss, and we will compare them to a control group. MATERIALS AND METHODS: Cross

  4. ABR Core examination preparation: results of a survey of fourth-year radiology residents who took the 2013 examination.

    Science.gov (United States)

    Shetty, Anup S; Grajo, Joseph R; Decker, Summer; Heitkamp, Darel E; DeStigter, Kristen K; Mezwa, Duane G; Deitte, Lori

    2015-01-01

    A survey was administered to fourth-year radiology residents after receiving their results from the first American Board of Radiology (ABR) Core examination in 2013. The purpose was to gather information regarding resources and study strategies to share with program directors and future resident classes. An online survey was distributed to examinees nationwide. The survey included free-response and multiple choice questions that covered examination results, perceived value of enumerated study resources, case-based and didactic teaching conferences, board reviews, study materials for noninterpretive skills, multidisciplinary conference attendance, and free-form comments. Two hundred sixty-six of 1186 residents who took the Core examination responded to the survey. Some resources demonstrated a significant difference in perceived value between residents who passed the examination and residents who failed, including internal board reviews (1.10, P multiple choice questions, audience response, and integration of clinical physics and patient safety topics compared to residents who failed. Radiology residents and residency programs have adapted their preparations for the ABR Core examination in a variety of ways. Certain practices and study tools, including daily conferences and internal board reviews, had greater perceived value by residents who passed the examination than by residents who failed. This survey provides insights that can be used to assess and modify current preparation strategies for the ABR Core examination. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  5. ABR and auditory P300 findings inchildren with ADHD

    Directory of Open Access Journals (Sweden)

    Schochat Eliane

    2002-01-01

    Full Text Available Auditory processing disorders (APD, also referred as central auditory processing disorders (CAPD and attention deficit hyperactivity disorders (ADHD have become popular diagnostic entities for school age children. It has been demonstrated a high incidence of comorbid ADHD with communication disorders and auditory processing disorder. The aim of this study was to investigate ABR and P300 auditory evoked potentials in children with ADHD, in a double-blind study. Twenty-one children, ages between 7 and 10 years, with a primary diagnosis of ADHD, participated in this experiment. Results showed that all children had normal ABR with normal latency for wave V. Results also showed that among 42 ears combined 52.38% did not have P300. For the medicated subjects we observed that among 28 ears, 42.85% did not have P300 and for the non-medicated 71.43% (N = 14 ears did not have P300. Our results suggest that the medicated subjects had more presence of P300 (57.15% than the non-medicated group (28.57%, though the absence of these potentials were high among the group - 52.38%.

  6. Lyme disease of the brainstem

    Energy Technology Data Exchange (ETDEWEB)

    Kalina, Peter [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Decker, Andrew [Northern Westchester Hospital Center, Department of Neurology, Mt. Kisco, NY (United States); Kornel, Ezriel [Northern Westchester Hospital Center, Division of Neurosurgery, Mt. Kisco, NY (United States); Halperin, John J. [North Shore University Hospital, Department of Neurology, Manhasset, NY (United States)

    2005-12-01

    Lyme disease is a multisystem infectious disease caused by the tick-borne spirochete, Borrelia burgdorferi. Central nervous system (CNS) involvement typically causes local inflammation, most commonly meningitis, but rarely parenchymal brain involvement. We describe a patient who presented with clinical findings suggesting a brainstem process. Magnetic resonance imaging (MRI) and positron emission tomography (PET) suggested a brainstem neoplasm. Prior to biopsy, laboratory evaluation led to the diagnosis of Lyme disease. Clinical and imaging abnormalities improved markedly following antimicrobial therapy. We describe Lyme disease involvement of the cerebellar peduncles with hypermetabolism on PET. Although MRI is the primary imaging modality for most suspected CNS pathology, the practical applications of PET continue to expand. (orig.)

  7. Brainstem Encoding of Aided Speech in Hearing Aid Users with Cochlear Dead Region(s

    Directory of Open Access Journals (Sweden)

    Hassaan, Mohammad Ramadan

    2016-02-01

    Full Text Available Introduction Neural encoding of speech begins with the analysis of the signal as a whole broken down into its sinusoidal components in the cochlea, which has to be conserved up to the higher auditory centers. Some of these components target the dead regions of the cochlea causing little or no excitation. Measuring aided speech-evoked auditory brainstem response elicited by speech stimuli with different spectral maxima can give insight into the brainstem encoding of aided speech with spectral maxima at these dead regions. Objective This research aims to study the impact of dead regions of the cochlea on speech processing at the brainstem level after a long period of hearing aid use. Methods This study comprised 30 ears without dead regions and 46 ears with dead regions at low, mid, or high frequencies. For all ears, we measured the aided speech-evoked auditory brainstem response using speech stimuli of low, mid, and high spectral maxima. Results Aided speech-evoked auditory brainstem response was producible in all subjects. Responses evoked by stimuli with spectral maxima at dead regions had longer latencies and smaller amplitudes when compared with the control group or the responses of other stimuli. Conclusion The presence of cochlear dead regions affects brainstem encoding of speech with spectral maxima perpendicular to these regions. Brainstem neuroplasticity and the extrinsic redundancy of speech can minimize the impact of dead regions in chronic hearing aid users.

  8. Hidrato de cloral para captação dos Potenciais Elétricos Auditivos Chloral Hydrate to Study Auditory Brainstem Response

    Directory of Open Access Journals (Sweden)

    Mariana Lopes Fávero

    2010-08-01

    Full Text Available O Hidrato de cloral é um sedativo usado em procedimentos pediátricos devido à pouca depressão respiratória e cardíaca. OBJETIVO: Avaliar a eficácia da droga para a captação do PEATE e sistematizar o seu emprego. MATERIAL E MÉTODO: Estudo prospectivo transversal com 41 crianças. A dose inicial de HC 10% foi de 50mg/kg com reforço de 6 mg/kg administrado após 30 minutos nos casos onde não houve sedação. A efetividade da droga foi determinada pela indução do sono até 1 hora após a administração da dose inicial. A ocorrência de sono foi correlacionada com as doses (50mg ou 56mg/kg, a idade, o peso e o sexo. RESULTADOS: As 41 crianças que participaram do estudo tomaram 50mg/kg e 23 dormiram em 30 minutos, 2 apresentaram depressão respiratória; 16 crianças tomaram reforço de 6mg/kg e 13 dormiram em mais 30 minutos. A dose total de 56mg/kg apresentou um efeito estatisticamente significante na indução do sono (pChloral Hydrate (CH is a sedative and hypnotic drug used in pediatric procedures owing to the low depressive effect it has on the respiratory and cardiac systems. AIM: To assess the efficacy of the drug in performing ABR and to systematize its use. MATERIALS AND METHODS: A prospective cross-sectional study with 41 children without history of heart or lung disease. The initial dose of CH at 10% was 50mg/Kg, with a boost dose of 6mg/Kg administered 30 minutes later in cases in which there was no sedation. Drug effectiveness was established by sleep induction by 1 hour after the administration of the initial dose. Sleep occurrence was correlated with doses (50mg or 56mg/Kg, age, weight and gender. RESULTS: All the 41 children who participated in the study took 50mg/kgof the agent and 23 of them slept within 30 minutes, 2 had respiratory complications, 16 had the 6mg/Kg boost dose and 13 fell asleep after 30 minutes. The 56 mg/kg dose presented a statistically significant effect on sleep induction (p<0.05 when compared

  9. Systematic Morphometry of Catecholamine Nuclei in the Brainstem

    Directory of Open Access Journals (Sweden)

    Domenico Bucci

    2017-11-01

    Full Text Available Catecholamine nuclei within the brainstem reticular formation (RF play a pivotal role in a variety of brain functions. However, a systematic characterization of these nuclei in the very same experimental conditions is missing so far. Tyrosine hydroxylase (TH immune-positive cells of the brainstem correspond to dopamine (DA-, norepinephrine (NE-, and epinephrine (E-containing cells. Here, we report a systematic count of TH-positive neurons in the RF of the mouse brainstem by using stereological morphometry. All these nuclei were analyzed for anatomical localization, rostro-caudal extension, volume, neuron number, neuron density, and mean neuronal area for each nucleus. The present data apart from inherent informative value wish to represent a reference for neuronal mapping in those studies investigating the functional anatomy of the brainstem RF. These include: the sleep-wake cycle, movement control, muscle tone modulation, mood control, novelty orienting stimuli, attention, archaic responses to internal and external stressful stimuli, anxiety, breathing, blood pressure, and innumerable activities modulated by the archaic iso-dendritic hard core of the brainstem RF. Most TH-immune-positive cells fill the lateral part of the RF, which indeed possesses a high catecholamine content. A few nuclei are medial, although conventional nosography considers all these nuclei as part of the lateral column of the RF. Despite the key role of these nuclei in psychiatric and neurological disorders, only a few of them aspired a great attention in biomedical investigation, while most of them remain largely obscure although intense research is currently in progress. A simultaneous description of all these nuclei is not simply key to comprehend the variety of brainstem catecholamine reticular neurons, but probably represents an intrinsically key base for understanding brain physiology and physiopathology.

  10. Assessment of Startup Fuel Options for the GNEP Advanced Burner Reactor (ABR)

    Energy Technology Data Exchange (ETDEWEB)

    Jon Carmack (062056); Kemal O. Pasamehmetoglu (103171); David Alberstein

    2008-02-01

    The Global Nuclear Energy Program (GNEP) includes a program element for the development and construction of an advanced sodium cooled fast reactor to demonstrate the burning (transmutation) of significant quantities of minor actinides obtained from a separations process and fabricated into a transuranic bearing fuel assembly. To demonstrate and qualify transuranic (TRU) fuel in a fast reactor, an Advanced Burner Reactor (ABR) prototype is needed. The ABR would necessarily be started up using conventional metal alloy or oxide (U or U, Pu) fuel. Startup fuel is needed for the ABR for the first 2 to 4 core loads of fuel in the ABR. Following start up, a series of advanced TRU bearing fuel assemblies will be irradiated in qualification lead test assemblies in the ABR. There are multiple options for this startup fuel. This report provides a description of the possible startup fuel options as well as possible fabrication alternatives available to the program in the current domestic and international facilities and infrastructure.

  11. Brainstem epidermoid cyst: An update

    Science.gov (United States)

    Patibandla, M. R.; Yerramneni, Vamsi Krishna; Mudumba, Vijaya S.; Manisha, Nukavarapu; Addagada, Gokul Chowdary

    2016-01-01

    The incidence of epidermoid tumors is between 1% and 2% of all intracranial tumors. The usual locations of epidermoid tumor are the parasellar region and cerebellopontine angle, and it is less commonly located in sylvian fissure, suprasellar region, cerebral and cerebellar hemispheres, and lateral and fourth ventricles. Epidermoid cysts located in the posterior fossa usually arise in the lateral subarachnoid cisterns, and those located in the brain stem are rare. These epidermoids contain cheesy and flaky white soft putty like contents. Epidermoid cysts are very slow growing tumors having a similar growth pattern of the epidermal cells of the skin and develop from remnants of epidermal elements during closure of the neural groove and disjunction of the surface ectoderm with neural ectoderm between the third and fifth weeks of embryonic life. We are presenting an interesting case of intrinsic brainstem epidermoid cyst containing milky white liquefied material with flakes in a 5-year-old girl. Diffusion-weighted imaging is definitive for the diagnosis. Ideal treatment of choice is removal of cystic components with complete resection of capsule. Although radical resection will prevent recurrence, in view of very thin firmly adherent capsule to brainstem, it is not always possible to do complete resection of capsule without any neurological deficits. PMID:27366244

  12. Surgical management of spontaneous hypertensive brainstem hemorrhage

    Directory of Open Access Journals (Sweden)

    Bal Krishna Shrestha

    2015-09-01

    Full Text Available Spontaneous hypertensive brainstem hemorrhage is the spontaneous brainstem hemorrhage associated with long term hypertension but not having definite focal or objective lesion. It is a catastrophic event which has a poor prognosis and usually managed conservatively. It is not uncommon, especially in eastern Asian populations, accounting approximately for 10% of the intracerebral hemorrhage. Before the advent of computed tomography, the diagnosis of brainstem hemorrhage was usually based on the clinical picture or by autopsy and believed to be untreatable via surgery. The introduction of computed tomography permitted to categorize the subtypes of brainstem hemorrhage with more predicted outcome. Continuous ongoing developments in the stereotactic surgery and microsurgery have added more specific surgical management in these patients. However, whether to manage conservatively or promptly with surgical evacuation of hematoma is still a controversy. Studies have shown that an accurate prognostic assessment based on clinical and radiological features on admission is critical for establishing a reasonable therapeutic approach. Some authors have advocate conservative management, whereas others have suggested the efficacy of surgical treatment in brainstem hemorrhage. With the widening knowledge in microsurgical techniques as well as neuroimaging technology, there seems to have more optimistic hope of surgical management of spontaneous hypertensive brainstem hemorrhage for better prognosis. Here we present five cases of severe spontaneous hypertensive brainstem hemorrhage patients who had undergone surgery; and explore the possibilities of surgical management in patients with the spontaneous hypertensive brainstem hemorrhage.

  13. Functional Ear (A)Symmetry in Brainstem Neural Activity Relevant to Encoding of Voice Pitch: A Precursor for Hemispheric Specialization?

    Science.gov (United States)

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Ananthakrishnan, Saradha; Bidelman, Gavin M.; Smalt, Christopher J.

    2011-01-01

    Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and…

  14. Imaging of adult brainstem gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Purohit, Bela, E-mail: purohitbela@yahoo.co.in; Kamli, Ali A.; Kollias, Spyros S.

    2015-04-15

    Highlights: •BSG are classified on MRI into diffuse low-grade, malignant, focal tectal and exophytic subtypes. •Their prognosis and treatment is variable and is almost similar to adult supratentorial gliomas. •This article illustrates the imaging of adult BSGs on MRI and FET-PET. •We also describe prognostic factors and the treatment options of these tumours. -- Abstract: Brainstem gliomas (BSGs) are uncommon in adults accounting for about 2% of all intracranial neoplasms. They are often phenotypically low-grade as compared to their more common paediatric counterparts. Since brainstem biopsies are rarely performed, these tumours are commonly classified according to their MR imaging characteristics into 4 subgroups: (a) diffuse intrinsic low-grade gliomas, (b) enhancing malignant gliomas, (c) focal tectal gliomas and (d) exophytic gliomas/other subtypes. The prognosis and treatment is variable for the different types and is almost similar to adult supratentorial gliomas. Radiotherapy (RT) with adjuvant chemotherapy is the standard treatment of diffuse low-grade and malignant BSGs, whereas, surgical resection is limited to the exophytic subtypes. Review of previous literature shows that the detailed imaging of adult BSGs has not received significant attention. This review illustrates in detail the imaging features of adult BSGs using conventional and advanced MR techniques like diffusion weighted imaging (DWI), diffusion tensor imaging (DTI), MR perfusion weighted imaging (PWI), MR spectroscopy (MRS), as well as {sup 18}F-fluoro-ethyl-tyrosine positron emission tomography ({sup 18}F-FET/PET). We have discussed the pertinent differences between childhood and adult BSGs, imaging mimics, prognostic factors and briefly reviewed the treatment options of these tumours.

  15. Delayed neuronal cell death in brainstem after transient brainstem ischemia in gerbils

    Directory of Open Access Journals (Sweden)

    Hakuba Nobuhiro

    2010-09-01

    Full Text Available Abstract Background Because of the lack of reproducible brainstem ischemia models in rodents, the temporal profile of ischemic lesions in the brainstem after transient brainstem ischemia has not been evaluated intensively. Previously, we produced a reproducible brainstem ischemia model of Mongolian gerbils. Here, we showed the temporal profile of ischemic lesions after transient brainstem ischemia. Results Brainstem ischemia was produced by occlusion of the bilateral vertebral arteries just before their entry into the transverse foramina of the cervical vertebrae of Mongolian gerbils. Animals were subjected to brainstem ischemia for 15 min, and then reperfused for 0 d (just after ischemia, 1 d, 3 d and 7 d (n = 4 in each group. Sham-operated animals (n = 4 were used as control. After deep anesthesia, the gerbils were perfused with fixative for immunohistochemical investigation. Ischemic lesions were detected by immunostaining for microtubule-associated protein 2 (MAP2. Just after 15-min brainstem ischemia, ischemic lesions were detected in the lateral vestibular nucleus and the ventral part of the spinal trigeminal nucleus, and these ischemic lesions disappeared one day after reperfusion in all animals examined. However, 3 days and 7 days after reperfusion, ischemic lesions appeared again and clusters of ionized calcium-binding adapter molecule-1(IBA-1-positive cells were detected in the same areas in all animals. Conclusion These results suggest that delayed neuronal cell death took place in the brainstem after transient brainstem ischemia in gerbils.

  16. Influence of general anaesthesia on the brainstem.

    Science.gov (United States)

    Bosch, L; Fernández-Candil, J; León, A; Gambús, P L

    2017-03-01

    The exact role of the brainstem in the control of body functions is not yet well known and the same applies to the influence of general anaesthesia on brainstem functions. Nevertheless in all general anaesthesia the anaesthesiologist should be aware of the interaction of anaesthetic drugs and brainstem function in relation to whole body homeostasis. As a result of this interaction there will be changes in consciousness, protective reflexes, breathing pattern, heart rate, temperature or arterial blood pressure to name a few. Brainstem function can be explored using three different approaches: clinically, analyzing changes in brain electric activity or using neuroimaging techniques. With the aim of providing the clinician anaesthesiologist with a global view of the interaction between the anaesthetic state and homeostatic changes related to brainstem function, the present review article addresses the influence of anaesthetic drug effects on brainstem function through clinical exploration of cranial nerves and reflexes, analysis of electric signals such as electroencephalographic changes and what it is known about brainstem through the use of imaging techniques, more specifically functional magnetic resonance imaging. Copyright © 2016 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Bayesian segmentation of brainstem structures in MRI

    DEFF Research Database (Denmark)

    Iglesias, Juan Eugenio; Van Leemput, Koen; Bhatt, Priyanka

    2015-01-01

    In this paper we present a method to segment four brainstem structures (midbrain, pons, medulla oblongata and superior cerebellar peduncle) from 3D brain MRI scans. The segmentation method relies on a probabilistic atlas of the brainstem and its neighboring brain structures. To build the atlas, w...... is able to detect differential effects of AD on the brainstem structures. The method will be implemented as part of the popular neuroimaging package FreeSurfer.......In this paper we present a method to segment four brainstem structures (midbrain, pons, medulla oblongata and superior cerebellar peduncle) from 3D brain MRI scans. The segmentation method relies on a probabilistic atlas of the brainstem and its neighboring brain structures. To build the atlas, we...... combined a dataset of 39 scans with already existing manual delineations of the whole brainstem and a dataset of 10 scans in which the brainstem structures were manually labeled with a protocol that was specifically designed for this study. The resulting atlas can be used in a Bayesian framework to segment...

  18. Brainstem morphological changes in Alzheimer's disease.

    Science.gov (United States)

    Lee, Ji Han; Ryan, John; Andreescu, Carmen; Aizenstein, Howard; Lim, Hyun Kook

    2015-05-06

    As brainstem nuclei are interconnected with several cortical structures and regulate several autonomic, cognitive, and behavioral functions, it might be important to place the brainstem within an important pathologic core in the progression of Alzheimer's disease (AD). Although there have been several postmortem studies reporting neuropathological alterations of the brainstem in AD, there has been no in-vivo structural neuroimaging study of the brainstem in the patients with AD. The aim of this study was to investigate differences in the brainstem volume and shape between patients with AD and elderly normal controls. Fifty AD patients (the Clinical Dementia Rating Scale ≥ 1) and 50 normal controls were recruited, and the brainstem volumes and deformations were compared between the AD and the controls. Patients with AD showed significant total volume [(mean ± SD) 21007 ± 1640 mm] reduction in the brainstem compared with the controls [(mean ± SD) 22530 ± 1750 mm] (Pfalse discovery rate corrected Pmemory impairment, sleep, and emotional disturbance in AD. However, further longitudinal studies might be needed to confirm these findings.

  19. Correlation between auditory brainstem recordings and morphology as seen through the scanning electron microscope

    International Nuclear Information System (INIS)

    Hultcrantz, M.

    1988-01-01

    Pregnant CBA/CBA mice were exposed to 0.5, 1 and 2 Grey (Gy), (1 Gy = 100 rad) in single doses with whole body gamma-irradiation on the 12th, 13th and 16th gestational days, respectively. The animals were tested at an age of one month for vestibular and cochlear function. Thereafter the inner ears were analyzed with scanning electron microscopy. A morphological analysis with cytocochleograms was performed. Morphological changes in the vestibular part showed gross malformations in the cristae ampullares. Hair cells of type I seemed to be more severely changed than hair cells type II. The macula utriculi also showed malformations of the otoconia. All these changes were more pronounced when the irradiation was given early during pregnancy and with the highest doses used, except the otoconia which were more injured when irradiated day 16 of gestation. No disturbances of the equilibrium reflexes were noted. In the cochlea a dose-dependent, time-related damage pattern was demonstrated with pathological changes of outer (OHC) and inner (IHC) hair cells. When tested electrophysiologically for auditory function with auditory brainstem recordings (ABR), elevated thresholds were revealed different in shape depending on when during pregnancy irradiation took place. A good correlation existed between the morphological changes as seen in the cytocochleograms and the functional changes documented with the ABR

  20. Correlation between auditory brainstem recordings and morphology as seen through the scanning electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Hultcrantz, M.

    1988-09-01

    Pregnant CBA/CBA mice were exposed to 0.5, 1 and 2 Grey (Gy), (1 Gy = 100 rad) in single doses with whole body gamma-irradiation on the 12th, 13th and 16th gestational days, respectively. The animals were tested at an age of one month for vestibular and cochlear function. Thereafter the inner ears were analyzed with scanning electron microscopy. A morphological analysis with cytocochleograms was performed. Morphological changes in the vestibular part showed gross malformations in the cristae ampullares. Hair cells of type I seemed to be more severely changed than hair cells type II. The macula utriculi also showed malformations of the otoconia. All these changes were more pronounced when the irradiation was given early during pregnancy and with the highest doses used, except the otoconia which were more injured when irradiated day 16 of gestation. No disturbances of the equilibrium reflexes were noted. In the cochlea a dose-dependent, time-related damage pattern was demonstrated with pathological changes of outer (OHC) and inner (IHC) hair cells. When tested electrophysiologically for auditory function with auditory brainstem recordings (ABR), elevated thresholds were revealed different in shape depending on when during pregnancy irradiation took place. A good correlation existed between the morphological changes as seen in the cytocochleograms and the functional changes documented with the ABR.

  1. WE-D-213-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Bevins, N.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  2. MO-F-204-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    McKenney, S. [Children’s National Medical Center (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  3. WE-D-213-00: Preparing for the ABR Diagnostic and Nuclear Medicine Physics Exams

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  4. WE-D-213-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Zambelli, J. [Spectrum Health, Grand Rapids, MI (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  5. WE-D-213-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Bevins, N. [Henry Ford Health System, Detroit, MI (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  6. MO-F-204-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Szczykutowicz, T. [University Wisconsin-Madison (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  7. MO-F-204-00: Preparing for the ABR Diagnostic and Nuclear Medical Physics Exams

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  8. WE-D-213-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Simiele, S. [University of Wisconsin-Madison (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  9. MO-F-204-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Zambelli, J. [Spectrum Health Grand Rapids (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  10. WE-D-213-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Simiele, S.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  11. WE-D-213-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Zambelli, J.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  12. MO-F-204-00: Preparing for the ABR Diagnostic and Nuclear Medical Physics Exams

    International Nuclear Information System (INIS)

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  13. MO-F-204-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Zambelli, J.

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  14. [On the terminology of auditory steady-state responses. What differentiates steady-state and transient potentials?].

    Science.gov (United States)

    Mühler, R

    2012-05-01

    Recording human auditory steady-state responses (ASSR) at different frequencies allows objective assessment of auditory thresholds. Common practice has been to record ASSR to pure tones that are sinusoidally modulated in amplitude and frequency. Recently, optimized chirp stimuli have been proposed to evoke transient as well as steady-state responses. Because of the resulting uncertainty about the different methods, this paper aims to reconsider the terminology of transient and steady-state responses. Two experiments demonstrate the smooth transition between transient and steady-state responses. In experiment 1, click-evoked auditory brainstem responses (ABR) were recorded over a wide range of stimulus repetition rates (24/s to 72/s). In experiment 2, auditory steady-state responses were recorded for the same stimulus repetition rates, using three different stimulus types: an amplitude modulated 1-kHz tone (AM), a 1-kHz tone-burst (TB) and a flat-spectrum chirp. Experiment 1 demonstrates the merging of the typical ABR wave complexes at higher repetition rates, forming a steady-state response. This effect can only be observed if the time window is extended far beyond the window traditionally used for clinical ABR recordings. Experiment 2 reveals similar ASSR amplitude spectra regardless of the stimulus type and repetition rate used. Steady-state responses can be evoked for a large variety of stimulus types and repetition rates. Thus, from a clinician's point of view, steady-state responses cannot be considered a new type of evoked responses. They differ from transient responses primarily in the frequency response method and the longer timeframe required.

  15. Lack of bcr and abr promotes hypoxia-induced pulmonary hypertension in mice.

    Directory of Open Access Journals (Sweden)

    Min Yu

    Full Text Available Bcr and Abr are GTPase activating proteins that specifically downregulate activity of the small GTPase Rac in restricted cell types in vivo. Rac1 is expressed in smooth muscle cells, a critical cell type involved in the pathogenesis of pulmonary hypertension. The molecular mechanisms that underlie hypoxia-associated pulmonary hypertension are not well-defined.Bcr and abr null mutant mice were compared to wild type controls for the development of pulmonary hypertension after exposure to hypoxia. Also, pulmonary arterial smooth muscle cells from those mice were cultured in hypoxia and examined for proliferation, p38 activation and IL-6 production. Mice lacking Bcr or Abr exposed to hypoxia developed increased right ventricular pressure, hypertrophy and pulmonary vascular remodeling. Perivascular leukocyte infiltration in the lungs was increased, and under hypoxia bcr-/- and abr-/- macrophages generated more reactive oxygen species. Consistent with a contribution of inflammation and oxidative stress in pulmonary hypertension-associated vascular damage, Bcr and Abr-deficient animals showed elevated endothelial leakage after hypoxia exposure. Hypoxia-treated pulmonary arterial smooth muscle cells from Bcr- or Abr-deficient mice also proliferated faster than those of wild type mice. Moreover, activated Rac1, phosphorylated p38 and interleukin 6 were increased in these cells in the absence of Bcr or Abr. Inhibition of Rac1 activation with Z62954982, a novel Rac inhibitor, decreased proliferation, p38 phosphorylation and IL-6 levels in pulmonary arterial smooth muscle cells exposed to hypoxia.Bcr and Abr play a critical role in down-regulating hypoxia-induced pulmonary hypertension by deactivating Rac1 and, through this, reducing both oxidative stress generated by leukocytes as well as p38 phosphorylation, IL-6 production and proliferation of pulmonary arterial smooth muscle cells.

  16. Recovery of Abnormal ABR in Neonates and Infants at Risk of Hearing Loss

    Directory of Open Access Journals (Sweden)

    Ioannis Psarommatis

    2017-01-01

    Full Text Available The purpose of this retrospective study is to present the clinical experience of a single institution on the recovery of ABR thresholds in a large population of neonates and infants at risk of hearing loss. Potential prognostic factors associated with this phenomenon were also investigated. Out of 2248 high risk infants, 384 had abnormal ABR at initial hearing evaluation and 168 of them had absent ABR or a threshold ≥80 dBnHL. From this subgroup, a significant percentage showed complete or partial recovery on reexamination (32.7% and 9.3%, resp., performed 4–6 months later. The presence of normal otoacoustic emissions was associated with the ABR restoration on reexamination. Moreover, the very young age at the initial hearing screening seems to be related to higher probabilities of false positive ABR. The potential recovery of hearing in HR infants raises concerns about the very early cochlear implantation in HR infants less than one year. Such a treatment modality should be decided cautiously and only after obtaining valid and stable objective and subjective hearing thresholds. This holds especially true for infants showing an auditory neuropathy profile, as they presented a much greater probability of ABR recovery.

  17. Recovery of Abnormal ABR in Neonates and Infants at Risk of Hearing Loss.

    Science.gov (United States)

    Psarommatis, Ioannis; Voudouris, Charalampos; Kapetanakis, Ioannis; Athanasiadi, Faselida; Douros, Konstantinos

    2017-01-01

    The purpose of this retrospective study is to present the clinical experience of a single institution on the recovery of ABR thresholds in a large population of neonates and infants at risk of hearing loss. Potential prognostic factors associated with this phenomenon were also investigated. Out of 2248 high risk infants, 384 had abnormal ABR at initial hearing evaluation and 168 of them had absent ABR or a threshold ≥80 dBnHL. From this subgroup, a significant percentage showed complete or partial recovery on reexamination (32.7% and 9.3%, resp.), performed 4-6 months later. The presence of normal otoacoustic emissions was associated with the ABR restoration on reexamination. Moreover, the very young age at the initial hearing screening seems to be related to higher probabilities of false positive ABR. The potential recovery of hearing in HR infants raises concerns about the very early cochlear implantation in HR infants less than one year. Such a treatment modality should be decided cautiously and only after obtaining valid and stable objective and subjective hearing thresholds. This holds especially true for infants showing an auditory neuropathy profile, as they presented a much greater probability of ABR recovery.

  18. Impairments in musical abilities reflected in the auditory brainstem: evidence from congenital amusia.

    Science.gov (United States)

    Lehmann, Alexandre; Skoe, Erika; Moreau, Patricia; Peretz, Isabelle; Kraus, Nina

    2015-07-01

    Congenital amusia is a neurogenetic condition, characterized by a deficit in music perception and production, not explained by hearing loss, brain damage or lack of exposure to music. Despite inferior musical performance, amusics exhibit normal auditory cortical responses, with abnormal neural correlates suggested to lie beyond auditory cortices. Here we show, using auditory brainstem responses to complex sounds in humans, that fine-grained automatic processing of sounds is impoverished in amusia. Compared with matched non-musician controls, spectral amplitude was decreased in amusics for higher harmonic components of the auditory brainstem response. We also found a delayed response to the early transient aspects of the auditory stimulus in amusics. Neural measures of spectral amplitude and response timing correlated with participants' behavioral assessments of music processing. We demonstrate, for the first time, that amusia affects how complex acoustic signals are processed in the auditory brainstem. This neural signature of amusia mirrors what is observed in musicians, such that the aspects of the auditory brainstem responses that are enhanced in musicians are degraded in amusics. By showing that gradients of music abilities are reflected in the auditory brainstem, our findings have implications not only for current models of amusia but also for auditory functioning in general. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  19. Dyslexia risk gene relates to representation of sound in the auditory brainstem.

    Science.gov (United States)

    Neef, Nicole E; Müller, Bent; Liebig, Johanna; Schaadt, Gesa; Grigutsch, Maren; Gunter, Thomas C; Wilcke, Arndt; Kirsten, Holger; Skeide, Michael A; Kraft, Indra; Kraus, Nina; Emmrich, Frank; Brauer, Jens; Boltze, Johannes; Friederici, Angela D

    2017-04-01

    Dyslexia is a reading disorder with strong associations with KIAA0319 and DCDC2. Both genes play a functional role in spike time precision of neurons. Strikingly, poor readers show an imprecise encoding of fast transients of speech in the auditory brainstem. Whether dyslexia risk genes are related to the quality of sound encoding in the auditory brainstem remains to be investigated. Here, we quantified the response consistency of speech-evoked brainstem responses to the acoustically presented syllable [da] in 159 genotyped, literate and preliterate children. When controlling for age, sex, familial risk and intelligence, partial correlation analyses associated a higher dyslexia risk loading with KIAA0319 with noisier responses. In contrast, a higher risk loading with DCDC2 was associated with a trend towards more stable responses. These results suggest that unstable representation of sound, and thus, reduced neural discrimination ability of stop consonants, occurred in genotypes carrying a higher amount of KIAA0319 risk alleles. Current data provide the first evidence that the dyslexia-associated gene KIAA0319 can alter brainstem responses and impair phoneme processing in the auditory brainstem. This brain-gene relationship provides insight into the complex relationships between phenotype and genotype thereby improving the understanding of the dyslexia-inherent complex multifactorial condition. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Analyzing AbrB-Knockout Effects through Genome and Transcriptome Sequencing of Bacillus licheniformis DW2

    Science.gov (United States)

    Shu, Cheng-Cheng; Wang, Dong; Guo, Jing; Song, Jia-Ming; Chen, Shou-Wen; Chen, Ling-Ling; Gao, Jun-Xiang

    2018-01-01

    As an industrial bacterium, Bacillus licheniformis DW2 produces bacitracin which is an important antibiotic for many pathogenic microorganisms. Our previous study showed AbrB-knockout could significantly increase the production of bacitracin. Accordingly, it was meaningful to understand its genome features, expression differences between wild and AbrB-knockout (ΔAbrB) strains, and the regulation of bacitracin biosynthesis. Here, we sequenced, de novo assembled and annotated its genome, and also sequenced the transcriptomes in three growth phases. The genome of DW2 contained a DNA molecule of 4,468,952 bp with 45.93% GC content and 4,717 protein coding genes. The transcriptome reads were mapped to the assembled genome, and obtained 4,102∼4,536 expressed genes from different samples. We investigated transcription changes in B. licheniformis DW2 and showed that ΔAbrB caused hundreds of genes up-regulation and down-regulation in different growth phases. We identified a complete bacitracin synthetase gene cluster, including the location and length of bacABC, bcrABC, and bacT, as well as their arrangement. The gene cluster bcrABC were significantly up-regulated in ΔAbrB strain, which supported the hypothesis in previous study of bcrABC transporting bacitracin out of the cell to avoid self-intoxication, and was consistent with the previous experimental result that ΔAbrB could yield more bacitracin. This study provided a high quality reference genome for B. licheniformis DW2, and the transcriptome data depicted global alterations across two strains and three phases offered an understanding of AbrB regulation and bacitracin biosynthesis through gene expression. PMID:29599755

  1. IMAGING WHITE MATTER IN HUMAN BRAINSTEM

    Directory of Open Access Journals (Sweden)

    Anastasia A Ford

    2013-07-01

    Full Text Available The human brainstem is critical for the control of many life-sustaining functions, such as consciousness, respiration, sleep, and transfer of sensory and motor information between the brain and the spinal cord. Most of our knowledge about structure and organization of white and gray matter within the brainstem is derived from ex vivo dissection and histology studies. However, these methods cannot be applied to study structural architecture in live human participants. Tractography from diffusion-weighted MRI may provide valuable insights about white matter organization within the brainstem in vivo. However, this method presents technical challenges in vivo due to susceptibility artifacts, functionally dense anatomy, as well as pulsatile and respiratory motion. To investigate the limits of MR tractography, we present results from high angular resolution diffusion imaging (HARDI of an intact excised human brainstem performed at 11.1T using isotropic resolution of 0.333, 1, and 2 mm, with the latter reflecting resolution currently used clinically. At the highest resolution, the dense fiber architecture of the brainstem is evident, but the definition of structures degrades as resolution decreases. In particular, the inferred corticopontine/corticospinal tracts (CPT/CST, superior (SCP and middle cerebellar peduncle (MCP, and medial lemniscus (ML pathways are clearly discernable and follow known anatomical trajectories at the highest spatial resolution. At lower resolutions, the CST/CPT, SCP, and MCP pathways are artificially enlarged due to inclusion of collinear and crossing fibers not inherent to these three pathways. The inferred ML pathways appear smaller at lower resolutions, indicating insufficient spatial information to successfully resolve smaller fiber pathways. Our results suggest that white matter tractography maps derived from the excised brainstem can be used to guide the study of the brainstem architecture using diffusion MRI in vivo.

  2. Brainstem evoked response audiometry in normal hearing subjects Estudo das latências das ondas dos potenciais auditivos de tronco encefálico em indivíduos normo-ouvintes

    Directory of Open Access Journals (Sweden)

    Maria Carolina Braga Norte Esteves

    2009-06-01

    Full Text Available Brainstem Evoked Response Audiometry (BERA is an objective and non-invasive method of hearing assessment which detects electrical activity from the inner ear to the inferior colliculus. AIM: To assess the hearing pathway in normal hearing individuals and compare differences associated with gender, age and ear side (left and right. Study Design: A retrospective study. MATERIALS AND METHODS: Sixty normal hearing individuals, aged between 09 and 66 years old, were subjected to clinical ENT examination and audiologic tests. RESULTS: Wave latencies differed significantly between males and females, although there were no differences regarding right or left ear sides. Comparing latency averages regarding age and gender we noticed important differences. By the same token, significant differences were also seen comparing this study with the information present in the handbook of the BERA device used and results published by Fukuda, in another study. CONCLUSION: Knowing the great importance of BERA, it is crucial that each service develops its own standards in order to enhance the accuracy of the electrophysiological diagnosis of the hearing pathway.Potencial Auditivo de Tronco Encefálico (PEATE é um método objetivo e não-invasivo de avaliação das vias auditivas, que detecta a atividade elétrica desde a orelha interna até o colículo inferior. OBJETIVO: Avaliar as vias auditivas em pacientes normo-ouvintes e comparar diferenças de acordo com sexo, idade e lado da orelha (direita e esquerda. Desenho do estudo: Estudo retrospectivo horizontal. MATERIAL E MÉTODOS: Sessenta pacientes normo-ouvintes, com idades entre 09 e 66 anos, foram submetidos a exame otorrinolaringológico e testes audiológicos. RESULTADOS: A disparidade entre as latências das ondas de homens e mulheres foi estatisticamente significante, entretanto, não mostrou diferença entre os lados das orelhas. Comparando as médias das latências de acordo com idade e sexo também foram

  3. Gamma Knife Treatment of Brainstem Metastases

    Directory of Open Access Journals (Sweden)

    Halloran E. Peterson

    2014-05-01

    Full Text Available The management of brainstem metastases is challenging. Surgical treatment is usually not an option, and chemotherapy is of limited utility. Stereotactic radiosurgery has emerged as a promising palliative treatment modality in these cases. The goal of this study is to assess our single institution experience treating brainstem metastases with Gamma Knife radiosurgery (GKRS. This retrospective chart review studied 41 patients with brainstem metastases treated with GKRS. The most common primary tumors were lung, breast, renal cell carcinoma, and melanoma. Median age at initial treatment was 59 years. Nineteen (46% of the patients received whole brain radiation therapy (WBRT prior to or concurrent with GKRS treatment. Thirty (73% of the patients had a single brainstem metastasis. The average GKRS dose was 17 Gy. Post-GKRS overall survival at six months was 42%, at 12 months was 22%, and at 24 months was 13%. Local tumor control was achieved in 91% of patients, and there was one patient who had a fatal brain hemorrhage after treatment. Karnofsky performance score (KPS >80 and the absence of prior WBRT were predictors for improved survival on multivariate analysis (HR 0.60 (p = 0.02, and HR 0.28 (p = 0.02, respectively. GKRS was an effective treatment for brainstem metastases, with excellent local tumor control.

  4. Treatment of low strength complex wastewater using an anaerobic baffled reactor (ABR).

    Science.gov (United States)

    Gopala Krishna, G V T; Kumar, Pramod; Kumar, Pradeep

    2008-11-01

    Treatment of a low strength complex wastewater of chemical oxygen demand (COD) around 500mg/L was studied in a 10L capacity laboratory scale anaerobic baffled reactor (ABR). It was operated at hydraulic retention times (HRTs) of 20, 15, 10, 8 and 6h. Corresponding organic loading rates (OLRs) were 0.6, 0.8, 1.2, 1.5 and 2kg COD/m3d. At every HRT (or OLR), pseudo steady state (PSS) was achieved. Even at maximum OLR of 2kg COD/m3d, COD and biochemical oxygen demand (BOD) removals exceeded 88%. Removal of particulate fraction of organics was found to be greater than soluble fraction. Compartment-wise studies of various parameters revealed that if the OLR was larger, the number of initial compartments played significant role in the removal of organics. The values of volatile fatty acids (VFA) demonstrated that hydrolysis and acidogenesis were the main biochemical activities in the initial few compartments. Based on the tracer studies, dead space in the ABR was found to range from 23% to 34%. The flow pattern in the ABR was classified as intermediate between plug flow and perfectly mixed flows. Observations from scanning electron micrographs (SEM) also suggested that distinct phase separation takes place in an ABR. Study of organic and hydraulic shock loads revealed that ABR was capable of sustaining the type of shock loads generally experienced at a sewage treatment plant (STP).

  5. Is enhanced MRI helpful in brainstem infarction?

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. M.; Shin, G. H.; Choi, W. S. [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1994-12-15

    To determine the role of MR contrast enhancement in evaluating time course of brainstem infarction. MR imaging with IV administration of gadopentetate dimeglumine was retrospectively reviewed in 43 patients with clinically and radiologically documented brainstem infarctions. The pattern of infarction was classified into spotty and patchy. Presence of parenchymal enhancement in infarction was evaluated. By location, there were 34 pontine, 3 midbrain, 6 medullary infarctions. The age of the infarctions ranged from 1 day to 9 months, with 5 patients scanned within 3 days and 10 scanned within 2 weeks of clinical ictus. Abnormalities on T2-weighted images were encountered in every case, with spotty pattern in 14 cases and patchy pattern in 29 cases. Parenchymal contrast enhancement was seen in 9 cases(20%), primarily occurring between days 8 and 20. MR contrast enhancement in brainstem infarction was infrequent that it may not be useful in the estimation of the age of infarction.

  6. Brainstem tumors: Current management and future directions

    Directory of Open Access Journals (Sweden)

    Pablo F Recinos

    2012-01-01

    Full Text Available Tumors arising in the brainstem comprise 10-20% of all pediatric central nervous system (CNS tumors and account for a small percentage in adults. The prognosis for these tumors was considered uniformly poor prior to the era of modern neuroimaging and the location was fraught with disaster being considered a ′no man′s land′ for neurosurgeons. Following the introduction of advanced imaging modalities and neurophysiological monitoring, striking progress has occurred in the management of these lesions. Brainstem tumors are presently classified based on their anatomic location, focality, and histopathology. This article reviews the current classification of brainstem tumors, current management options, and future directions in the treatment for these rare tumors.

  7. Round window closure affects cochlear responses to suprathreshold stimuli.

    Science.gov (United States)

    Cai, Qunfeng; Whitcomb, Carolyn; Eggleston, Jessica; Sun, Wei; Salvi, Richard; Hu, Bo Hua

    2013-12-01

    The round window acts as a vent for releasing inner ear pressure and facilitating basilar membrane vibration. Loss of this venting function affects cochlear function, which leads to hearing impairment. In an effort to identify functional changes that might be used in clinical diagnosis of round window atresia, the current investigation was designed to examine how the cochlea responds to suprathreshold stimuli following round window closure. Prospective, controlled, animal study. A rat model of round window occlusion (RWO) was established. With this model, the thresholds of auditory brainstem responses (ABR) and the input/output (IO) functions of distortion product otoacoustic emissions (DPOAEs) and acoustic startle responses were examined. Round window closure caused a mild shift in the thresholds of the auditory brainstem response (13.5 ± 9.1 dB). It also reduced the amplitudes of the distortion product otoacoustic emissions and the slope of the input/output functions. This peripheral change was accompanied by a significant reduction in the amplitude, but not the threshold, of the acoustic startle reflex, a motor response to suprathreshold sounds. In addition to causing mild increase in the threshold of the auditory brainstem response, round window occlusion reduced the slopes of both distortion product otoacoustic emissions and startle reflex input/output functions. These changes differ from those observed for typical conductive or sensory hearing loss, and could be present in patients with round window atresia. However, future clinical observations in patients are needed to confirm these findings. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  8. Exposures to fine particulate matter (PM2.5) and ozone above USA standards are associated with auditory brainstem dysmorphology and abnormal auditory brainstem evoked potentials in healthy young dogs.

    Science.gov (United States)

    Calderón-Garcidueñas, Lilian; González-González, Luis O; Kulesza, Randy J; Fech, Tatiana M; Pérez-Guillé, Gabriela; Luna, Miguel Angel Jiménez-Bravo; Soriano-Rosales, Rosa Eugenia; Solorio, Edelmira; Miramontes-Higuera, José de Jesús; Gómez-Maqueo Chew, Aline; Bernal-Morúa, Alexia F; Mukherjee, Partha S; Torres-Jardón, Ricardo; Mills, Paul C; Wilson, Wayne J; Pérez-Guillé, Beatriz; D'Angiulli, Amedeo

    2017-10-01

    Delayed central conduction times in the auditory brainstem have been observed in Mexico City (MC) healthy children exposed to fine particulate matter (PM 2.5 ) and ozone (O 3 ) above the current United States Environmental Protection Agency (US-EPA) standards. MC children have α synuclein brainstem accumulation and medial superior olivary complex (MSO) dysmorphology. The present study used a dog model to investigate the potential effects of air pollution on the function and morphology of the auditory brainstem. Twenty-four dogs living in clean air v MC, average age 37.1 ± 26.3 months, underwent brainstem auditory evoked potential (BAEP) measurements. Eight dogs (4 MC, 4 Controls) were analysed for auditory brainstem morphology and histopathology. MC dogs showed ventral cochlear nuclei hypotrophy and MSO dysmorphology with a significant decrease in cell body size, decreased neuronal packing density with regions in the nucleus devoid of neurons and marked gliosis. MC dogs showed significant delayed BAEP absolute wave I, III and V latencies compared to controls. MC dogs show auditory nuclei dysmorphology and BAEPs consistent with an alteration of the generator sites of the auditory brainstem response waveform. This study puts forward the usefulness of BAEPs to study auditory brainstem neurodegenerative changes associated with air pollution in dogs. Recognition of the role of non-invasive BAEPs in urban dogs is warranted to elucidate novel neurodegenerative pathways link to air pollution and a promising early diagnostic strategy for Alzheimer's Disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. PEATE automático em recém nascidos de risco: estudo da sensibilidade e especificidade Automatic ABR in newborns risk: study of sensitivity and specificity

    Directory of Open Access Journals (Sweden)

    Rosanna Mariangela Giaffredo Angrisani

    2012-04-01

    female gender. Evaluation procedures consisted of transient otoacoustic emissions(TOAEs, A-ABR and diagnostic ABR carried out in the same week. RESULTS: from the 186 evaluated newborns, 156 (83.9% showed normal hearing. Conductive hearing loss was verified in nine neonates (4.8%, seven bilateral and two unilateral. Cochlear hearing loss was observed in five neonates (2.7%, one unilateral and four bilateral. Central evidences were observed in eleven neonates (5.9% and one neonate was diagnosed with auditory neuropathy spectrum disorder (0,5%. In four cases, we found a maturational delay in the first evaluation with normal result within one month. In the comparison of A-ABR with diagnostic ABR, high sensitivity rates were observed (99% and higher in the identification of cochlear, conductive, central and auditory neuropathy. Specificity rate of A-ABR was 100% for auditory neuropathy, 75% for right ear and 60% for left ear cochlear hearing losses and 54.5% for right ear and 63.6% for the left ear central abnormalities. For conductive hearing losses, specificity was low (lower than 43%. CONCLUSION: A-ABR was efficient in the identification of auditory neuropathies with high sensitivity and specificity rates. However, false negative responses were observed in the group diagnosed with cochlear and conductive hearing losses, central abnormalities and maturational delay.

  10. Neuromyelitis Optica Lesion Mimicking Brainstem Glioma

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-12-01

    Full Text Available A 12-year-old girl who presented with weakness of the left extremities and right sided sixth cranial nerve palsy had neuromyelitis optica (NMO mistaken for brainstem glioma on MRI, in a report from Brain Research Institute, Yonsei University College of Medicine,Seoul, Republic of KoreaNeuromyelitis Optica, Optic-Spinal Syndrome, Spectroscopy.

  11. The value of intraoperative EABRs in auditory brainstem implantation.

    Science.gov (United States)

    Anwar, Abbas; Singleton, Alison; Fang, Yixin; Wang, Binhuan; Shapiro, William; Roland, J Thomas; Waltzman, Susan B

    2017-10-01

    To compare the intraoperative electrically evoked auditory brainstem response (EABR) morphologies between neurofibromatosis II (NF2) adult auditory brainstem implant (ABI) recipients who had auditory percepts post-operatively and those who did not and between NF2 adult ABI recipients and non-NF2 pediatric ABI recipients. This was a retrospective case series at a single tertiary academic referral center examining all ABI recipients from 1994 to 2016, which included 34 NF2 adults and 11 non-NF2 children. The morphologies of intraoperative EABRs were evaluated for the number of waveforms showing a response, the number of positive peaks in those responses, and the latencies of each of these peaks. 27/34 adult NF2 patients and 9/10 children had EABR waveforms. 20/27 (74.0%) of the adult patients and all of the children had ABI devices that stimulated post-operatively. When comparing the waveforms between adults who stimulated and those who did not stimulate, the proportion of total number of intraoperative EABR peaks to total possible peaks was significantly higher for the adults who stimulated than for those who did not (p auditory percepts based on the placement of the array providing the highest number of total peaks. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Activation of Brainstem Neurons by Underwater Diving in the Rat

    Science.gov (United States)

    Panneton, W. Michael; Gan, Qi; Le, Jason; Livergood, Robert S.; Clerc, Philip; Juric, Rajko

    2012-01-01

    The mammalian diving response is a powerful autonomic adjustment to underwater submersion greatly affecting heart rate, arterial blood pressure, and ventilation. The bradycardia is mediated by the parasympathetic nervous system, arterial blood pressure is mediated via the sympathetic system and still other circuits mediate the respiratory changes. In the present study we investigate the cardiorespiratory responses and the brainstem neurons activated by voluntary diving of trained rats, and, compare them to control and swimming animals which did not dive. We show that the bradycardia and increase in arterial blood pressure induced by diving were significantly different than that induced by swimming. Neuronal activation was calculated after immunohistochemical processing of brainstem sections for Fos protein. Labeled neurons were counted in the caudal pressor area, the medullary dorsal horn, subnuclei of the nucleus tractus solitarii (NTS), the nucleus raphe pallidus (RPa), the rostroventrolateral medulla, the A5 area, the nucleus locus coeruleus, the Kölliker–Fuse area, and the external lateral and superior lateral subnuclei of the parabrachial nucleus. All these areas showed significant increases in Fos labeling when data from voluntary diving rats were compared to control rats and all but the commissural subnucleus of the NTS, A5 area, and RPa were significantly different from swimming rats. These data provide a substrate for more precise experiments to determine the role of these nuclei in the reflex circuits driving the diving response. PMID:22563319

  13. Activation of brainstem neurons by underwater diving in the rat

    Directory of Open Access Journals (Sweden)

    W Michael ePanneton

    2012-05-01

    Full Text Available The mammalian diving response is a powerful autonomic adjustment to underwater submersion greatly affecting heart rate, arterial blood pressure and ventilation. The bradycardia is known to be mediated by the parasympathetic nervous system, arterial blood pressure is mediated via the sympathetic system and still other circuits mediate the respiratory changes. In the present study we investigate the cardiorespiratory responses and the brainstem neurons activated by voluntary diving of trained rats, and, compare them to control and swimming animals which did not dive. We show that the bradycardia and increase in arterial blood pressure induced by diving were significantly different that induced by swimming. Neuronal activation was calculated after immunohistochemical processing of brainstem sections for Fos protein. Labeled neurons were counted in the caudal pressor area, the medullary dorsal horn, subnuclei of the nucleus tractus solitarii, the nucleus raphe pallidus, the rostroventrolateral medulla, the A5 area, the nucleus locus coeruleus, the Kölliker-Fuse area and the external lateral and superior lateral subnuclei of the parabrachial nucleus. All these areas showed significant increases in Fos labeling when data from voluntary diving rats were compared to control rats and all but the commissural subnucleus of the nucleus tractus solitarii, A5 area, and raphe pallidus were different from swimming rats. These data provide a substrate for more precise experiments to determine the role of these nuclei in the reflex circuits driving the diving response.

  14. Hydrogen production from diluted molasses by anaerobic hydrogen producing bacteria in an anaerobic baffled reactor (ABR)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jianzheng; Zhu, Gefu; Ren, Nanqi; Bo, Lixin; He, Junguo [Harbin Institute of Technology, Harbin (China). School of Municipal and Environmental Engineering; Li, Baikun [University of Connecticut, Storrs, CT (United States). Department of Civil and Environmental Engineering

    2007-10-15

    Hydrogen production from diluted molasses by anaerobic fermentation bacteria was investigated in a three-compartment anaerobic baffled reactor (ABR) with an effective volume of 27.48 L. After being inoculated with aerobic activated sludge and operated at chemical oxygen demand (COD) of 5000 mg/L and temperature of 35 C for 26 days, the ABR achieved stable ethanol-type fermentation. The liquid fermentation products, including volatile fatty acids (VFAs) and ethanol, stabilized at 1254, 2053, and 2761 mg/L in the three compartments, respectively. Effluent pH, oxidation-reduction potential (ORP), and alkalinity ranged at 4.3-4.4, -241 to -249mV, and 306-334mgCaCO{sub 3}/L, respectively. The hydrogen yield of the ABR was 32.51 L/d at the stable operation status, specific hydrogen production rate of anaerobic activated sludge was 0.13 L/g MLVSS d, and the substrate conversion rate was 0.13 L/g COD. Hydrogen yields, fermentation types, and acclimatization durations varied in each compartment, with the 1st compartment having lowest hydrogen yield but longest acclimatization duration and the 2nd and 3rd compartments having higher hydrogen yields but shorter acclimatization durations. The study found that the individual compartment configuration in the ABR system provided a favorable environment for different types of anaerobic bacteria. Compared with complete stirring tank reactor (CSTR), the ABR system had a better operation stability and microbial activity, which led to higher substrate conversion rate and hydrogen production ability. (author)

  15. Bickerstaff’s brainstem encephalitis: a case report

    Directory of Open Access Journals (Sweden)

    Toghae M

    2010-11-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Bickerstaff's brainstem encephalitis (BBE is a very uncommon central nervous system disease with unknown etiology. As it is usually responsive to treatment, the diagnosis this disease is important. It seems There is no reported Bickerstaff's brainstem encephalitis case in Iran."n"nCase presentation: An 83 year old woman presented with vertigo, ataxia and dysarthria from a week prior to admission. Her 2 weighted MRI revealed high intensity lesions in the pons area. She received treatment with impression of ischemic stroke. After few days, lower extremities became weak symmetrically and deep tendon reflexes depressed. Deep sensory loss was noted too. The EMG-NCV studies showed acute polyneuropathy and in CSF examination increased protein content was noted. The patient improved after IVIG and corticosteroid therapy with impression of Bickerstaff's brainstem encephalitis."n"nConclusion: In spite of severe initial presentation, Bickerstaff's brainstem encephalitis has a good prognosis if it diagnosed and treated properly. Although clinical features is too important, but paraclinical work up are necessary to diagnose this syndrome.

  16. Encoding of speech sounds at auditory brainstem level in good and poor hearing aid performers.

    Science.gov (United States)

    Shetty, Hemanth Narayan; Puttabasappa, Manjula

    Hearing aids are prescribed to alleviate loss of audibility. It has been reported that about 31% of hearing aid users reject their own hearing aid because of annoyance towards background noise. The reason for dissatisfaction can be located anywhere from the hearing aid microphone till the integrity of neurons along the auditory pathway. To measure spectra from the output of hearing aid at the ear canal level and frequency following response recorded at the auditory brainstem from individuals with hearing impairment. A total of sixty participants having moderate sensorineural hearing impairment with age range from 15 to 65 years were involved. Each participant was classified as either Good or Poor Hearing aid Performers based on acceptable noise level measure. Stimuli /da/ and /si/ were presented through loudspeaker at 65dB SPL. At the ear canal, the spectra were measured in the unaided and aided conditions. At auditory brainstem, frequency following response were recorded to the same stimuli from the participants. Spectrum measured in each condition at ear canal was same in good hearing aid performers and poor hearing aid performers. At brainstem level, better F 0 encoding; F 0 and F 1 energies were significantly higher in good hearing aid performers than in poor hearing aid performers. Though the hearing aid spectra were almost same between good hearing aid performers and poor hearing aid performers, subtle physiological variations exist at the auditory brainstem. The result of the present study suggests that neural encoding of speech sound at the brainstem level might be mediated distinctly in good hearing aid performers from that of poor hearing aid performers. Thus, it can be inferred that subtle physiological changes are evident at the auditory brainstem in a person who is willing to accept noise from those who are not willing to accept noise. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier

  17. Towards an optimal paradigm for simultaneously recording cortical and brainstem auditory evoked potentials.

    Science.gov (United States)

    Bidelman, Gavin M

    2015-02-15

    Simultaneous recording of brainstem and cortical event-related brain potentials (ERPs) may offer a valuable tool for understanding the early neural transcription of behaviorally relevant sounds and the hierarchy of signal processing operating at multiple levels of the auditory system. To date, dual recordings have been challenged by technological and physiological limitations including different optimal parameters necessary to elicit each class of ERP (e.g., differential adaptation/habitation effects and number of trials to obtain adequate response signal-to-noise ratio). We investigated a new stimulus paradigm for concurrent recording of the auditory brainstem frequency-following response (FFR) and cortical ERPs. The paradigm is "optimal" in that it uses a clustered stimulus presentation and variable interstimulus interval (ISI) to (i) achieve the most ideal acquisition parameters for eliciting subcortical and cortical responses, (ii) obtain an adequate number of trials to detect each class of response, and (iii) minimize neural adaptation/habituation effects. Comparison between clustered and traditional (fixed, slow ISI) stimulus paradigms revealed minimal change in amplitude or latencies of either the brainstem FFR or cortical ERP. The clustered paradigm offered over a 3× increase in recording efficiency compared to conventional (fixed ISI presentation) and thus, a more rapid protocol for obtaining dual brainstem-cortical recordings in individual listeners. We infer that faster recording of subcortical and cortical potentials might allow more complete and sensitive testing of neurophysiological function and aid in the differential assessment of auditory function. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Interictal dysfunction of a brainstem descending modulatory center in migraine patients.

    Directory of Open Access Journals (Sweden)

    Eric A Moulton

    Full Text Available The brainstem contains descending circuitry that can modulate nociceptive processing (neural signals associated with pain in the dorsal horn of the spinal cord and the medullary dorsal horn. In migraineurs, abnormal brainstem function during attacks suggest that dysfunction of descending modulation may facilitate migraine attacks, either by reducing descending inhibition or increasing facilitation. To determine whether a brainstem dysfunction could play a role in facilitating migraine attacks, we measured brainstem function in migraineurs when they were not having an attack (i.e. the interictal phase.Using fMRI (functional magnetic resonance imaging, we mapped brainstem activity to heat stimuli in 12 episodic migraine patients during the interictal phase. Separate scans were collected to measure responses to 41 degrees C and noxious heat (pain threshold+1 degrees C. Stimuli were either applied to the forehead on the affected side (as reported during an attack or the dorsum of the hand. This was repeated in 12 age-gender-matched control subjects, and the side tested corresponded to that in the matched migraine patients. Nucleus cuneiformis (NCF, a component of brainstem pain modulatory circuits, appears to be hypofunctional in migraineurs. 3 out of the 4 thermal stimulus conditions showed significantly greater NCF activation in control subjects than the migraine patients.Altered descending modulation has been postulated to contribute to migraine, leading to loss of inhibition or enhanced facilitation resulting in hyperexcitability of trigeminovascular neurons. NCF function could potentially serve as a diagnostic measure in migraine patients, even when not experiencing an attack. This has important implications for the evaluation of therapies for migraine.

  19. Cerebral and brainstem electrophysiologic activity during euthanasia with pentobarbital sodium in horses.

    Science.gov (United States)

    Aleman, M; Williams, D C; Guedes, A; Madigan, J E

    2015-01-01

    An overdose of pentobarbital sodium administered i.v. is the most commonly used method of euthanasia in veterinary medicine. Determining death after the infusion relies on the observation of physical variables. However, it is unknown when cortical electrical activity and brainstem function are lost in a sequence of events before death. To examine changes in the electrical activity of the cerebral cortex and brainstem during an overdose of pentobarbital sodium solution for euthanasia. Our testing hypothesis is that isoelectric pattern of the brain in support of brain death occurs before absence of electrocardiogram (ECG) activity. Fifteen horses requiring euthanasia. Prospective observational study. Horses with neurologic, orthopedic, and cardiac illnesses were selected and instrumented for recording of electroencephalogram, electrooculogram, brainstem auditory evoked response (BAER), and ECG. Physical and neurologic (brainstem reflexes) variables were monitored. Loss of cortical electrical activity occurred during or within 52 seconds after the infusion of euthanasia solution. Cessation of brainstem function as evidenced by a lack of brainstem reflexes and disappearance of the BAER happened subsequently. Despite undetectable heart sounds, palpable arterial pulse, and mean arterial pressure, recordable ECG was the last variable to be lost after the infusion (5.5-16 minutes after end of the infusion). Overdose of pentobarbital sodium solution administered i.v. is an effective, fast, and humane method of euthanasia. Brain death occurs within 73-261 seconds of the infusion. Although absence of ECG activity takes longer to occur, brain death has already occurred. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  20. [Optimization of Energy Saving Measures with ABR-MBR Integrated Process].

    Science.gov (United States)

    Wu, Peng; Lu, Shuang-jun; Xu, Yue-zhong; Liu, Jie; Shen, Yao-liang

    2015-08-01

    High energy consumption and membrane fouling are important factors that limit the wide use of membrane bioreactor (MBR). In order to reduce energy consumption and delay the process of membrane fouling, the process of anaerobic baffled reactor (ABR)-MBR was used to treat domestic sewage. The structure of the process and conditions of nitrogen and phosphorus removal were optimized in this study. The results showed that energy consumption was reduced by 43% through optimizing the structure of ABR-MBR process. Meanwhile, the process achieved a high level of COD, NH: -N, TN and TP removal, with the average removal efficiencies of 91%, 85%, 76% and 86%, respectively. In addition, the added particulate media could effectively delay membrane fouling, while the formation process of membrane fouling was changed. The extracted amount of carbohydrates increased while the amount of proteins decreased. Finally, the potential was enhanced for the practical application of MBR.

  1. A proposed medical physics curriculum: preparing for the 2013 ABR examination.

    Science.gov (United States)

    Nachiappan, Arun C; Wynne, David M; Katz, David P; Willis, Marc H; Bushong, Stewart C

    2011-01-01

    The upcoming ABR examination format for radiology residents is undergoing significant changes in 2013. This requires adaptation of the didactic curriculum for radiology residents entering in July 2010 to meet these changes. Physics will now be incorporated into the core (qualifying) examination during the third year of residency, instead of being tested as a separate examination that was often taken earlier in residency training in past years. In this article, the authors discuss the past, present, and future of medical physics instruction and outline a revised medical physics curriculum for radiology residents that has been internally approved for implementation at the authors' institution and has not been advocated by any society or by the ABR. Starting with this article, the authors hope to encourage a discussion of physics curriculum revision with other institutions. Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  2. A Neurophysiological Approach for Evaluating Noise-Induced Sleep Disturbance: Calculating the Time Constant of the Dynamic Characteristics in the Brainstem

    Directory of Open Access Journals (Sweden)

    Junta Tagusari

    2016-03-01

    Full Text Available Chronic sleep disturbance induced by traffic noise is considered to cause environmental sleep disorder, which increases the risk of cardiovascular disease, stroke, diabetes and other stress-related diseases. However, noise indices for the evaluation of sleep disturbance are not based on the neurophysiological process of awakening regulated by the brainstem. In this study, through the neurophysiological approach, we attempted (1 to investigate the thresholds of awakening due to external stimuli in the brainstem; (2 to evaluate the dynamic characteristics in the brainstem and (3 to verify the validity of existing noise indices. Using the mathematical Phillips–Robinson model, we obtained thresholds of awakening in the brainstem for different durations of external stimuli. The analysis revealed that the brainstem seemed insensitive to short stimuli and that the response to external stimuli in the brainstem could be approximated by a first-order lag system with a time constant of 10–100 s. These results suggest that the brainstem did not integrate sound energy as external stimuli, but neuroelectrical signals from auditory nerve. To understand the awakening risk accumulated in the brainstem, we introduced a new concept of “awakening potential” instead of sound energy.

  3. Feasibility of an Anaerobic Baffled Reactor (ABR In Treating Starch Industry Wastewater

    Directory of Open Access Journals (Sweden)

    Ali Assadi

    2007-03-01

    Full Text Available The anaerobic baffled reactor (ABR includes a mixed anaerobic culture separated into compartments and a novel process with a series of vertical baffles at each compartment. It dose not require granulation for its operation, resulting in shorter start-up time. In this study, the feasibility of the ABR process was investigated for the treatment of wheat flour starch wastewater. Simple gravity settling was used to remove suspended solids from the starch wastewater and used as feed. Start-up of a reactor (13.5L with five compartments using a diluted feed of approximately 4500 mg/L chemical oxygen demand (COD was accomplished in about 9 weeks using seed sludge from the anaerobic digester of a municipal wastewater treatment plant. The reactor with a hydraulic retention time (HRT of 72 h at 35°C and an initial organic loading rate (OLR of 1.2 kgCOD/m3.d showed a removal efficiency of 61% COD. The best reactor performance was observed with an organic loading rate of 2.5 kgCOD/m3.d (or hydraulic retention time of 2.45 d when a COD conversion of 67% was achieved. The main advantage of using an ABR comes from its compartmentalized structure. The first compartment of an ABR may act as a buffer zone to all toxic and inhibitory materials in the feed and, thus, allows the later compartments to be loaded with a relatively harmless, more uniform, and mostly acidified influent. In this respect, the later compartments would be more likely to support active populations of the relatively sensitive methanogenic bacteria.

  4. Relationships between behavior, brainstem and cortical encoding of seen and heard speech in musicians and non-musicians.

    Science.gov (United States)

    Musacchia, Gabriella; Strait, Dana; Kraus, Nina

    2008-07-01

    Musicians have a variety of perceptual and cortical specializations compared to non-musicians. Recent studies have shown that potentials evoked from primarily brainstem structures are enhanced in musicians, compared to non-musicians. Specifically, musicians have more robust representations of pitch periodicity and faster neural timing to sound onset when listening to sounds or both listening to and viewing a speaker. However, it is not known whether musician-related enhancements at the subcortical level are correlated with specializations in the cortex. Does musical training shape the auditory system in a coordinated manner or in disparate ways at cortical and subcortical levels? To answer this question, we recorded simultaneous brainstem and cortical evoked responses in musician and non-musician subjects. Brainstem response periodicity was related to early cortical response timing across all subjects, and this relationship was stronger in musicians. Peaks of the brainstem response evoked by sound onset and timbre cues were also related to cortical timing. Neurophysiological measures at both levels correlated with musical skill scores across all subjects. In addition, brainstem and cortical measures correlated with the age musicians began their training and the years of musical practice. Taken together, these data imply that neural representations of pitch, timing and timbre cues and cortical response timing are shaped in a coordinated manner, and indicate corticofugal modulation of subcortical afferent circuitry.

  5. Avaliação dos achados ao exame dos potenciais evocados do tronco cerebral em indivíduos com síndrome de West Evaluation of the brainstem evoked potentials in West syndrome

    Directory of Open Access Journals (Sweden)

    Alfredo Lopes Pereira Filho

    2004-01-01

    Full Text Available A síndrome de West é um tipo de espasmo infantil caracterizado por encefalopatia epiléptica associado a espasmos em flexão e deficiência mental de instalação no primeiro ano de vida e de etiologia incerta. Acredita-se ser determinada por diferentes fatores etiológicos como infeção intrauterina, esclerose tuberosa, asfixia perinatal ou afecções pós-natais. FORMA DE ESTUDO: Observacional coorte com corte transversal. MATERIAL E MÉTODO: No presente estudo dez pacientes com Síndrome de West foram submetidos ao exame de Potencial Evocado de Tronco Cerebral (BERA para avaliar o envolvimento do tronco cerebral e das vias auditivas a este nível. RESULTADO: Os achados anormais ao BERA incluem alteração na morfologia das curvas com reprodutibilidade apenas de onda I e II, (caso 7, aumento do intervalo interpico da onda I-V (casos 1, 2 e 9, aumento da proporção de amplitude da onda I/V (caso 8 e alteração do limiar eletrofisiológico (caso 7. Tais achados ao BERA sugerem que a disfunção do sistema nervoso resulte principalmente da hipogênese ou degeneração das células nervosas, em parte como resultado da dismielinização. CONCLUSÃO: Os autores recomendam o uso de estudos eletrofisiológicos para avaliar a disfunção do sistema nervoso central no paciente com suspeita de espasmo infantil.The West syndrome is a pediatric disease that involves muscular spasm, mental deficiency and epileptic encephalopathy. This disease tends to be noticed in the first year of life and has no etiology known. It is believed to be caused by different etiology factors as uterine infection, tuberous sclerosis, perinatal asphyxia, or post-born diseases. STUDY DESIGN: Observacional cohort with transversal cut. MATERIAL AND METHOD: In this study, ten West Syndrome patients were submitted to Auditory Brainstem Response (ABR to evaluate the involvement of the hearing system. RESULTS: The abnormal results consisted in morphological alterations (case 7

  6. WE-D-213-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    International Nuclear Information System (INIS)

    MacDougall, R.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  7. MO-F-204-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    MacDougall, R. [Boston Children’s Hospital (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  8. WE-D-213-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    MacDougall, R. [Children’s Hospital (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  9. MO-F-204-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    International Nuclear Information System (INIS)

    MacDougall, R.

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  10. Brainstem: neglected locus in neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Lea T Grinberg

    2011-07-01

    Full Text Available The most frequent neurodegenerative diseases (NDs are Alzheimer’s disease (AD, Parkinson’s disease (PD, and frontotemporal lobar degeneration associated with protein TDP-43 (FTLD-TDP. Neuropathologically, NDs are characterized by abnormal intracellular and extracellular protein deposits and by disease-specific neuronal death. Practically all terminal stages of NDs are clinically associated with dementia. Therefore, major attention was directed to protein deposits and neuron loss in supratentorial (telencephalic brain regions in the course of NDs. This was also true for PD, although the pathological hallmark of PD is degeneration of pigmented neurons of the brainstem’s substantia nigra. However, PD pathophysiology was explained by dopamine depletion in the telencephalic basal ganglia due to insufficiency and degeneration of the projection neurons located in substantia nigra. In a similar line of argumentation AD- and FTLD-related clinical deficits were exclusively explained by supratentorial allo- and neocortical laminar neuronal necrosis. Recent comprehensive studies in AD and PD early stages found considerable and unexpected involvement of brainstem nuclei, which could have the potential to profoundly change our present concepts on origin, spread, and early clinical diagnosis of these diseases. In contrast with PD and AD, few studies addressed brainstem involvement in the course of the different types of FTLD-TDP. Some of the results, including ours, disclosed a higher and more widespread pathology than anticipated. The present review will focus mainly on the impact of brainstem changes during the course of the most frequent NDs including PD, AD, and FTLD-TDP, with special emphasis on the need for more comprehensive research on FTLDs.

  11. Avaliação da onda V da audiometria de tronco cerebral de crianças reprovadas na triagem auditiva neonatal Evaluation of the five wave from auditory brain response of children who not passed in neonatal screening

    Directory of Open Access Journals (Sweden)

    Viviane Camargo Marques

    2003-12-01

    Full Text Available Já está bem estabelecido a importância do diagnóstico precoce das disacusias em neonatos. Muito se tem falado da triagem auditiva neonatal (TAN, mas pouco se comenta do encaminhamento e seguimento das crianças com emissão otoacústica (EOA alterada. A audiometria de tronco cerebral (ABR é a próxima etapa para o diagnóstico de disacusia nesta faixa etária. OBJETIVOS: Os objetivos deste trabalho são avaliar a adesão ao programa de TAN e avaliar as ABRs das crianças reprovadas na TAN, concentrando a análise nos limiares obtidos e na latência da onda V. TIPO DE ESTUDO: Clínico prospectivo. MATERIAL E MÉTODO: Análise de 75 ABRs de crianças atendidas no serviço de EOA da Maternidade de Campinas. RESULTADOS: A maioria das crianças apresentou ABR com limiares e latências dentro dos valores normais. A alteração mais encontrada foi o aumento da latência da onda V, que pode ser decorrente da incompleta mielinização do sistema nervoso central, da presença de secreção em ouvido médio e de alterações retrococleares. CONCLUSÃO: Concluímos que o aumento da latência da onda V é a alteração mais freqüente nas ABRs; que muitos pacientes se perdem durante a execução do protocolo de triagem auditiva, retardando ou impossibilitando o diagnóstico correto e precoce e que a maior parte das crianças reprovadas nas otoemissões acústicas têm limiar eletrofisiológico auditivo normal.It is very well established the importance of early diagnostic of hearing loss. Everybody speaks about neonatal screening, but just a few people comment about the children who not passed on screening. The auditory brainstem response (ABR is the next step of the diagnostic. The aim of this paper is evaluate the ABRs from children who not passed on screening, looking for the threshold and the latency of the five wave. STUDY DESIGN: Clinical prospective. MATERIAL AND METHOD: 75 ABR were analyzed. RESULTS: A great number of exams was normal. The most

  12. Radiotherapy of midbrain and brainstem tumours in children

    International Nuclear Information System (INIS)

    Skowronska-Gardas, Anna

    1991-01-01

    From 1984-1987 in the First Radiotherapy Department in the Warsaw Centre of Oncology, 11 children with midbrain (group 1) and 14 with brainstem (group 2) tumours were treated. In 4 cases diagnostic biopsy was performed and in 21 diagnosis was established by CT scan. All children were treated with megavoltage radiotherapy with a Co-60 unit. The initial radiotherapy treatment volume was determined from CT scan and was subsequently adapted to include whole brain or whole cranio-spinal axis, depending on the response to treatment. Improvement or stabilization of disease in 23/25 (92 percent) of cases was observed. Total survival, longer than 3 years in 14/25 (56 percent) was observed, while 9/11 (82 percent) survived >3 years (NED) in group 1, and 4/14 (28 percent) in group 2. Ninety-two percent of living children have normal school life, with minimal or no neurological defects. (author). 26 refs.; 4 tabs

  13. Brainstem tolerance to conformal radiotherapy of skull base tumors

    International Nuclear Information System (INIS)

    Debus, J.; Hug, E.B.; Liebsch, N.J.; O'Farrel, D.; Finkelstein, D.; Efird, J.; Munzenrider, J.E.

    1997-01-01

    Purpose: The aim of this study was to analyze the long-term incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Methods and Materials: Between 1974 and 1995, 367 patients with chordomas (n = 195) and chondrosarcomas (n = 172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. Following 3D treatment planning with delineation of target volumes and critical nontarget structures dose distributions and dose-volume histograms were calculated. Radiotherapy was given an 1.8 Gy or CGE (=Cobalt Gray Equivalent) dose per fraction, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Results: Follow-up time ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem toxicity was observed in 17 of 367 patients attributable to treatment, resulting in death of three patients. Actuarial rates of 5 and 10-year high-grade toxicity-free survival were 94 and 88%, respectively. Increased risk of brainstem toxicity was significantly associated with maximum dose to brainstem, volume of brainstem receiving ≥50 CGE, ≥55 CGE, and ≥60 CGE, number of surgical procedures, and prevalence of diabetes or high blood pressure. Multivariate analysis identified three independent factors as important prognosticators: number of surgical procedures (p < 0.001), volume of the brainstem receiving 60 CGE (p < 0.001), and prevalence of diabetes (p < 0.01). Conclusions: Tolerance of brainstem to fractionated radiotherapy appears to be a steep function of tissue volume included in high dose regions rather than the maximum dose of brainstem alone. In addition, presence of predisposing factors as well as extent of surgical manipulation can significantly lower brainstem tolerance in the individual patient

  14. Investigation of auditory brainstem function in elderly diabetic patients with presbycusis.

    Science.gov (United States)

    Kovacií, Jelena; Lajtman, Zoran; Ozegović, Ivan; Knezević, Predrag; Carić, Tomislav; Vlasić, Ana

    2009-01-01

    We performed brainstem auditory evoked potential (BAEP) examinations in 100 patients older than 60 years and having type I diabetes mellitus and presbycusis. The aim of our investigation was to compare the BAEP results of this group with those of healthy controls with presbycusis and to look for possible correlations between alteration of the auditory brainstem function and the aging of elderly diabetic patients. Absolute and interpeak latencies of all waves were prolonged significantly in the study group of diabetic patients. The amplitudes of all waves I through V were diminished in the study group as compared to those in the control group, with statistical significance present for all waves. Analysis of the latencies (waves I, II, I, and V), interpeak latencies (I-V), and amplitudes (I, II, III, and V) of BAEP revealed a significant difference between those of diabetics and those of healthy elderly controls with presbycusis. These data support a hypothesis that there is a brainstem neuropathy in diabetes mellitus that can be assessed with auditory brainstem response testing even in the group of elderly patients with sensorineural hearing loss.

  15. Microglia modulate brainstem serotonergic expression following neonatal sustained hypoxia exposure: implications for sudden infant death syndrome.

    Science.gov (United States)

    MacFarlane, P M; Mayer, C A; Litvin, D G

    2016-06-01

    Neonatal sustained hypoxia exposure modifies brainstem microglia and serotonin expression. The altered brainstem neurochemistry is associated with impaired ventilatory responses to acute hypoxia and mortality. The deleterious effects of sustained hypoxia exposure can be prevented by an inhibitor of activated microglia. These observations demonstrate a potential cause of the brainstem serotonin abnormalities thought to be involved in sudden infant death syndrome. We showed previously that the end of the second postnatal week (days P11-15) represents a period of development during which the respiratory neural control system exhibits a heightened vulnerability to sustained hypoxia (SH, 11% O2 , 5 days) exposure. In the current study, we investigated whether the vulnerability to SH during the same developmental time period is associated with changes in brainstem serotonin (5-HT) expression and whether it can be prevented by the microglia inhibitor minocycline. Using whole-body plethysmography, SH attenuated the acute (5 min) hypoxic ventilatory response (HVR) and caused a high incidence of mortality compared to normoxia rats. SH also increased microglia cell numbers and decreased 5-HT immunoreactivity in the nucleus of the solitary tract (nTS) and dorsal motor nucleus of the vagus (DMNV). The attenuated HVR, mortality, and changes in nTS and DMNV immunoreactivity was prevented by minocycline (25 mg kg(-1) /2 days during SH). These data demonstrate that the 5-HT abnormalities in distinct respiratory neural control regions can be initiated by prolonged hypoxia exposure and may be modulated by microglia activity. These observations share several commonalities with the risk factors thought to underlie the aetiology of sudden infant death syndrome, including: (1) a vulnerable neonate; (2) a critical period of development; (3) evidence of hypoxia; (4) brainstem gliosis (particularly the nTS and DMNV); and (5) 5-HT abnormalities. © 2015 The Authors. The Journal of

  16. Tinnitus in vascular conflict of the eighth cranial nerve : a surgical pathophysiological approach to ABR changes

    NARCIS (Netherlands)

    De Ridder, Dirk; Heijneman, Karin; Haarman, Benno; van der Loo, Elsa; Langguth, B; Hajak, G; Kleinjung, T; Cacace, A; Moller, AR

    2007-01-01

    Some forms of tinnitus are associated with a blood vessel being in close contact with the auditory nerve near its entrance into the brainstem. The outcome of operations for tinnitus, moving the blood vessel off the nerve (microvascular decompression operations, MVD) is less successful than

  17. Treatment of low-strength soluble wastewater using an anaerobic baffled reactor (ABR).

    Science.gov (United States)

    Gopala Krishna, G V T; Kumar, Pramod; Kumar, Pradeep

    2009-01-01

    Treatment of low-strength soluble wastewater (COD approximately 500 mg/L) was studied using an eight chambered anaerobic baffled reactor (ABR). At pseudo steady-state (PSS), the average total and soluble COD values (COD(T) and COD(S)) at 8h hydraulic retention time (HRT) were found to be around 50 and 40 mg/L, respectively, while at 10h HRT average COD(T) and COD(S) values were of the order of 47 and 37 mg/L, respectively. COD and BOD (3 day, 27 degrees C) removal averaged more than 90%. Effluent conformed to Indian standards laid down for BOD (less than 30 mg/L). Reactor effluent characteristics exhibited very low values of standard deviation indicating excellent reactor stability at PSS in terms of effluent characteristics. Based on mass balance calculations, more than 60% of raw wastewater COD was estimated to be recovered as CH(4) in the gas phase. Compartment-wise profiles indicated that most of the BOD and COD got reduced in the initial compartments only. Sudden drop in pH (7.8-6.7) and formation of volatile fatty acids (VFA) (53-85 mg/L) were observed in the first compartment due to acidogenesis and acetogenesis. The pH increased and VFA concentration decreased longitudinally down the reactor. Residence time distribution (RTD) studies revealed that the flow pattern in the ABR was neither completely plug-flow nor perfectly mixed. Observations from scanning electron micrographs (SEM) suggest that distinct phase separation takes place in an ABR.

  18. MO-F-16A-03: AAPM Online Learning Support of New ABR MOC Requirements

    International Nuclear Information System (INIS)

    Bloch, C; Ogburn, J; Woodward, M

    2014-01-01

    In 2002 the American Board of Radiology (ABR) discontinued issuing lifetime board certification. After that time diplomates received a timelimited certificate and must participate in the Maintenance of Certification (MOC) program in order to maintain their certification. Initially certificates were issued with a 10 year expiration period and the MOC had requirements to be met over that 10 year period. The goal was to demonstrate continuous maintenance of clinical competency, however some diplomates were attempting to fulfill most or all of the requirements near the end of the 10 year period. This failed to meet the continuous aspect of the goal and so the ABR changed to a sliding 3-year window. This was done to recognize that not every year would be the same, but that diplomates should be able to maintain a reasonable average over any 3 year period.A second significant change occurred in 2013. The initial requirements included 20 selfassessment modules (SAMs) over the original 10 year term. SAMs are a special type of continuing education (CE) credit that were an addition to the 250 standard CE credits required over the 10 year period. In 2013, however, the new requirement is 75 CE credits over the previous 3 years, of which 25 must include self-assessment. Effectively this raised the self-assessment requirement from 20 in 10 years to 25 in 3 years. Previously SAMs were an interactive presentation available in limited quantities at live meetings. However, the new requirement is not for SAMs but CE-SA which includes SAMs, but also includes the online quizzes provided at the AAPM online learning center. All credits earned at the AAPM online learning center fulfill the ABR SA requirement.This talk will be an interactive demonstration of the AAPM online learning center along with a discussion of the MOC requirements

  19. MRI findings of multiple sclerosis involving the brainstem

    International Nuclear Information System (INIS)

    Park, Jeong Hoon; Jeong, Hae Woong; Kim, Hyun Jin; Cho, Jae Kwoeng; Kim, Chang Soo

    2001-01-01

    To describe MRI findings of multiple sclerosis involving the brainstem. Among 35 cases of clinically definite multiple sclerosis, the authors retrospectively analysed 20 in which the brainstem was involved. MR images were analysed with regard to involvement sites in the brainstem or other locations, signal intensity, multiplicity, shape, enhancement pattern, and contiguity of brainstem lesions with cisternal or ventricular CSF space. The brainstem was the only site of involvement in five cases (25%), while simultaneous involvement of the brainstem and other sites was observed in 15 cases (75%). No case involved only the midbrain or medulla oblongata, and simultaneous involvement of the midbrain, pons and medulla oblongata was noted in 12 cases (60%). The most frequently involved region of the brainstem was the medulla oblongata (n=13; 90%), followed by the pons (n=17; 85%) and the midbrain (n=16; 80%). Compared with normal white matter, brainstem lesions showed low signal intensity on T1 weighted images, and high signal intensity on T2 weighted, proton density weighted, and FLAIR images. In 17 cases (85%), multiple intensity was observed, and the shape of lesions varied: oval, round, elliptical, patchy, crescentic, confluent or amorphous were seen on axial MR images, and in 14 cases (82%), coronal or sagittal scanning showed that lesions were long and tubular. Contiguity between brainstem lesions and cisternal or ventricular CSF space was seen in all cases (100%) involving midbrain (16/16) and medulla oblongata (18/18) and in 15 of 17 (88%) involving the pons. Contrast enhancement was apparent in 7 of 12 cases (58%). In the brainstem, MRI demonstrated partial or total contiguity between lesions and cisternal or ventricular CSF space, and coronal or sagittal images showed that lesions were long and tubuler

  20. Potenciais Evocados Auditivos de Estado Estável no diagnóstico audiológico infantil: uma comparação com os Potenciais Evocados Auditivos de Tronco Encefálico Steady-state auditory evoked responses in audiological diagnosis in children: a comparison with brainstem evoked auditory responses

    Directory of Open Access Journals (Sweden)

    Gabriela Ribeiro Ivo Rodrigues

    2010-02-01

    Full Text Available Os Potenciais Evocados Auditivos de Estado Estável (PEAEE têm sido apontados como uma técnica promissora na avaliação audiológica infantil. OBJETIVO: Investigar o nível de concordância entre os resultados dos PEAEE e dos Potenciais Evocados Auditivos de Tronco Encefálico (PEATE-clique em um grupo de crianças com perda auditiva sensorioneural, averiguando assim a aplicabilidade clínica desta técnica na avaliação audiológica infantil. FORMA DE ESTUDO: Clínico prospectivo de coorte transversal. MATERIAL E MÉTODO: 15 crianças com idade entre dois e 36 meses e diagnóstico de perda auditiva sensorioneural. A concordância entre as respostas dos dois testes foi avaliada por meio do coeficiente de correlação intraclasse e o teste de McNemar comparou os dois testes quanto à probabilidade de ocorrência de resposta. RESULTADOS: Os coeficientes de correlação encontrados foram 0,70; 0,64; 0,49; 0,69; 0,63 e 0,68 respectivamente para as frequências de 1, 2, 4, 1-2, 2-4 e 1-2-4kHz. No teste de McNemar foi obtido p=0.000, indicando que a probabilidade de se obter resposta presente nos dois testes não é igual, sendo maior nos PEAEE. CONCLUSÃO: A boa concordância observada entre as técnicas sugere que um exame pode ser complementar ao outro. Os PEAEE, entretanto, promoveram informações adicionais nos casos de perdas severas e profundas, acrescentando dados importantes para a reabilitação destas crianças e proporcionando maior precisão no diagnóstico audiológico.Auditory Steady-State Responses (ASSR are being recognized as a promising technique in the assessment of hearing in children. AIM: To investigate the agreement level between results obtained from ASSR and click-ABR in a group of children with sensorineural hearing loss, in order to study the clinical applicability of this technique to evaluate the hearing status in young children. STUDY DESIGN: clinical prospective with a cross-sectional cohort. MATERIALS AND METHODS

  1. Hypothyroidism alters antioxidant defence system in rat brainstem during postnatal development and adulthood.

    Science.gov (United States)

    Jena, Srikanta; Bhanja, Shravani

    2014-08-01

    The present investigation was carried out to evaluate alterations in oxidative stress parameter [lipid peroxidation (LPx)] and antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)] in rat brainstem in response to neonatal hypothyroidism during development (from birth to 7, 15 and 30 days old) and adulthood (90 days old). Hypothyroidism in rats was induced by feeding the lactating mothers (from the day of parturition till weaning, 25 days old) or directly to the pups with 0.05 % [6-n-propyl 2-thiouracil (PTU)] in drinking water. Increased level of LPx was observed in brainstem of 7 days old hypothyroid rats, accompanied by augmented activities of SOD and GPx. In 15 and 30 days old hypothyroid rat brainstem, a significant decline in LPx was observed. Significantly increased activities of CAT and GPx were observed in 15 and 30 days PTU-treated rats. Decreased level of LPx was observed in brainstem of rats treated with PTU from birth to 30 days followed by withdrawal up to 90 days of age (transient hypothyroidism) as compared to control and persistent treatment of PTU up to 90 days of age. Activities of CAT and GPx were decreased in persistent hypothyroid rats of 90 days old with respect to control and transient hypothyroid rats. On the other hand, SOD activity was decreased in both persistent and transient hypothyroid rats with respect to control rats. These results suggest that the PTU-induced neonatal hypothyroidism modulates the antioxidant defence system during postnatal development and adulthood in brainstem of rats.

  2. L-type CaV1.2 deletion in the cochlea but not in the brainstem reduces noise vulnerability: implication for CaV1.2 mediated control of cochlear BDNF expression

    Directory of Open Access Journals (Sweden)

    Annalisa eZuccotti

    2013-08-01

    Full Text Available Voltage-gated L-type Ca2+ channels (L-VGCCs like CaV1.2 are assumed to play a crucial role for controlling release of trophic peptides including brain-derived neurotrophic factor (BDNF. In the inner ear of the adult mouse, beside the well described L-VGCC CaV1.3, also CaV1.2 is expressed. Due to lethality of constitutive CaV1.2 KO mice, the function of this ion channel as well as its putative relationship to BDNF in the auditory system is entirely elusive. We recently described that BDNF plays a differential role for inner hair cell (IHC vesicles release in normal and traumatized condition. To elucidate a presumptive role of CaV1.2 during this process, two tissue-specific conditional mouse lines were generated. To distinguish the impact of CaV1.2 on the cochlea from that on feedback loops from higher auditory centers CaV1.2 was deleted, in one mouse line, under the Pax2 promoter (CaV1.2Pax2 leading to a deletion in the spiral ganglion neurons (SGN, dorsal cochlear nucleus (DCN, and inferior colliculus (IC. In the second mouse line, the Egr2 promoter was used for deleting CaV1.2 (CaV1.2Egr2 in auditory brainstem nuclei. In both mouse lines normal hearing threshold and equal number of IHC release sites were observed. We found a slight reduction of auditory brainstem response (ABR wave I amplitudes in the CaV1.2Pax2 mice but not in the CaV1.2Egr2 mice. After noise exposure, CaV1.2Pax2 mice had less pronounced hearing loss that correlated with maintenance of ribbons in IHCs and less reduced activity in auditory nerve fibers, as well as in higher brain centers at supra-threshold sound stimulation. As reduced cochlear BDNF mRNA levels were found in CaV1.2Pax2 mice, we suggest that a CaV1.2 dependent step may participate in triggering part of the beneficial and deteriorating effects of cochlear BDNF in intact systems and during noise exposure through a pathway that is independent of Cav1.2 function in efferent circuits.

  3. Time-varying auditory gain control in response to double-pulse stimuli in harbour porpoises is not mediated by a stapedial reflex

    Directory of Open Access Journals (Sweden)

    Asger Emil Munch Schrøder

    2017-04-01

    Full Text Available Echolocating animals reduce their output level and hearing sensitivity with decreasing echo delays, presumably to stabilize the perceived echo intensity during target approaches. In bats, this variation in hearing sensitivity is formed by a call-induced stapedial reflex that tapers off over time after the call. Here, we test the hypothesis that a similar mechanism exists in toothed whales by subjecting a trained harbour porpoise to a series of double sound pulses varying in delay and frequency, while measuring the magnitudes of the evoked auditory brainstem responses (ABRs. We find that the recovery of the ABR to the second pulse is frequency dependent, and that a stapedial reflex therefore cannot account for the reduced hearing sensitivity at short pulse delays. We propose that toothed whale auditory time-varying gain control during echolocation is not enabled by the middle ear as in bats, but rather by frequency-dependent mechanisms such as forward masking and perhaps higher-order control of efferent feedback to the outer hair cells.

  4. Partial Nitrification and Denitrifying Phosphorus Removal in a Pilot-Scale ABR/MBR Combined Process.

    Science.gov (United States)

    Wu, Peng; Xu, Lezhong; Wang, Jianfang; Huang, Zhenxing; Zhang, Jiachao; Shen, Yaoliang

    2015-11-01

    A pilot-scale combined process consisting of an anaerobic baffled reactor (ABR) and an aerobic membrane bioreactor (MBR) for the purpose of achieving easy management, low energy demands, and high efficiencies on nutrient removal from municipal wastewater was investigated. The process operated at room temperature with hydraulic retention time (HRT) of 7.5 h, recycle ratio 1 of 200%, recycle ratio 2 of 100%, and dissolved oxygen (DO) of 1 mg/L and achieved good effluent quality with chemical oxygen demand (COD) of 25 mg/L, NH4 (+)-N of 4 mg/L, total nitrogen (TN) of 11 mg/L, and total phosphorus (TP) of 0.7 mg/L. The MBR achieved partial nitrification, and NO2 (-)-N has been accumulated (4 mg/L). Efficient short-cut denitrification was occurred in the ABR with a TN removal efficiency of 51%, while the role of denitrification and phosphorus removal removed partial TN (14%). Furthermore, nitrogen was further removed (11%) by simultaneous nitrification and denitrification in the MBR. In addition, phosphorus accumulating organisms in the MBR sufficiently uptake phosphorus; thus, effluent TP further reduced with a TP removal efficiency of 84%. Analysis of fluorescence in situ hybridization (FISH) showed that ammonia oxidizing bacteria (AOB) and phosphorus accumulating organisms (PAOs) were enriched in the process. In addition, the accumulation of NO2 (-)-N was contributed to the inhibition on the activities of the NOB rather than its elimination.

  5. ABrIL - Advanced Brain Imaging Lab : a cloud based computation environment for cooperative neuroimaging projects.

    Science.gov (United States)

    Neves Tafula, Sérgio M; Moreira da Silva, Nádia; Rozanski, Verena E; Silva Cunha, João Paulo

    2014-01-01

    Neuroscience is an increasingly multidisciplinary and highly cooperative field where neuroimaging plays an important role. Neuroimaging rapid evolution is demanding for a growing number of computing resources and skills that need to be put in place at every lab. Typically each group tries to setup their own servers and workstations to support their neuroimaging needs, having to learn from Operating System management to specific neuroscience software tools details before any results can be obtained from each setup. This setup and learning process is replicated in every lab, even if a strong collaboration among several groups is going on. In this paper we present a new cloud service model - Brain Imaging Application as a Service (BiAaaS) - and one of its implementation - Advanced Brain Imaging Lab (ABrIL) - in the form of an ubiquitous virtual desktop remote infrastructure that offers a set of neuroimaging computational services in an interactive neuroscientist-friendly graphical user interface (GUI). This remote desktop has been used for several multi-institution cooperative projects with different neuroscience objectives that already achieved important results, such as the contribution to a high impact paper published in the January issue of the Neuroimage journal. The ABrIL system has shown its applicability in several neuroscience projects with a relatively low-cost, promoting truly collaborative actions and speeding up project results and their clinical applicability.

  6. Transcranial sonography of brainstem structures in panic disorder.

    Science.gov (United States)

    Šilhán, Petr; Jelínková, Monika; Walter, Uwe; Pavlov Praško, Ján; Herzig, Roman; Langová, Kateřina; Školoudík, David

    2015-10-30

    Panic disorder has been associated with altered serotonin metabolism in the brainstem raphe. The aim of study was to evaluate the BR echogenicity on transcranial sonography (TCS) in panic disorder. A total of 96 healthy volunteers were enrolled in the "derivation" cohort, and 26 healthy volunteers and 26 panic disorder patients were enrolled in the "validation" cohort. TCS echogenicity of brainstem raphe and substantia nigra was assessed on anonymized images visually and by means of digitized image analysis. Significantly reduced brainstem raphe echogenicity was detected more frequently in panic disorder patients than in controls using both visual (68% vs. 31%) and digitized image analysis (52% vs. 12%). The optimal cut-off value of digitized brainstem raphe echogenicity indicated the diagnosis of panic disorder with a sensitivity of 64% and a specificity of 73%, and corresponded to the 30th percentile in the derivation cohort. Reduced brainstem raphe echogenicity was associated with shorter treatment duration, and, by trend, lower severity of anxiety. No relationship was found between echogenicity of brainstem raphe or substantia nigra and age, gender, severity of panic disorder, or severity of depression. Patients with panic disorder exhibit changes of brainstem raphe on TCS suggesting an alteration of the central serotonergic system. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. A brainstem variant of reversible posterior leukoencephalopathy syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kitaguchi, H.; Tomimoto, H.; Terada, K. [Kyoto University, Department of Neurology, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Miki, Y.; Yamamoto, A. [Kyoto University, Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Satoi, H.; Kanda, M. [Ijinkai Takeda General Hospital, Department of Neurology, Fushimi-ku, Kyoto (Japan); Fukuyama, H. [Kyoto University, Human Brain Research Center, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan)

    2005-09-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is caused by various heterogeneous factors, the commonest being hypertension, followed by nonhypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. Patients with RPLS exhibit bilateral white and gray matter abnormalities in the posterior aspects of the cerebral hemispheres. However, this syndrome may affect the brainstem predominantly, and these cases are designated as hypertensive brainstem encephalopathy. We present here two patients with reversible brainstem encephalopathy: one with hypertension and the other without hypertension. These patients presented with swelling and diffuse hyperintensities of the brainstem in fluid-attenuated inversion-recovery (FLAIR) and T2-weighted MRI, but with relatively mild clinical symptoms. They recovered without major neurological deficits, but had residual lacunar lesions in the pons. Reversible brainstem encephalopathy with characteristic MRI features was found in both hypertensive and nonhypertensive patients. These patients were diagnosed with a brainstem variant of RPLS, which is potentially fully reversible after an adequate treatment, and therefore should be carefully differentiated from other brainstem disease conditions. (orig.)

  8. Brainstem evoked response in bus drivers with noise-induced hearing loss Audiometria de tronco encefálico em motoristas de ônibus com perda auditiva induzida pelo ruído

    Directory of Open Access Journals (Sweden)

    Adriana Silveira Santos

    2009-10-01

    Full Text Available Studies carried out by Brainstem Evoked Auditory Potentials (BEAP in Noise-Induced Hearing Loss (NIHL workers show different results in relation to neuronal involvement, not involving bus drivers as study object. AIM: to use BEAP in a prospective case/control clinical study to check whether or not there is neural auditory pathway involvement in bus drivers with NIHL. MATERIALS AND METHODS: we selected 50 bus drivers between 27 and 40 years with mild to moderate NIHL, and 20 individuals between 29 and 40 years with normal hearing and without prior history of noise exposure. BEAP tests were carried out and the traces were analyzed. RESULTS: in the NIHL group, the auditory thresholds in 3, 4 and 6 kHz were significantly higher in the left ear. In the NIHL group, potentials PI, PIII and/or PV were not present in a small number of the individuals; we observed a statistically significant increase in PI, PIII and PV absolute latencies, (LIP LIP I-III interpeak latencies, bilaterally and LIP I-V in the left ear. CONCLUSION: in the NIHL group, besides sensorial injury, changes in BEAP latencies suggest an early functional injury of the first auditory pathway afferent neuron.Estudos realizados com os Potenciais Auditivos Evocados de Tronco Encefálico (PEATE em trabalhadores com Perda Auditiva Induzida pelo Ruído (PAIR apresentam resultados díspares em relação ao comprometimento neuronal, além de não contemplar motoristas de ônibus como objeto de estudo. OBJETIVO: Avaliar pelo PEATE, em estudo clínico de série caso/controle, prospectivo, se há comprometimento das vias auditivas neurais em motoristas de ônibus com PAIR. MATERIAL E MÉTODO: Foram selecionados 50 motoristas de ônibus entre 27 e 40 anos portadores de PAIR leve a moderada; e 20 sujeitos entre 29 e 40 anos com audibilidade normal e sem antecedentes de exposição a ruído. Os PEATEs foram realizados e os traçados analisados. RESULTADOS: No grupo PAIR, os limiares auditivos em 3, 4

  9. Repetitive Diving in Trained Rats Still Increases Fos Production in Brainstem Neurons after Bilateral Sectioning of the Anterior Ethmoidal Nerve.

    Science.gov (United States)

    McCulloch, Paul F; Warren, Erik A; DiNovo, Karyn M

    2016-01-01

    This research was designed to investigate the role of the anterior ethmoidal nerve (AEN) during repetitive trained diving in rats, with specific attention to activation of afferent and efferent brainstem nuclei that are part of this reflexive response. The AEN innervates the nose and nasal passages and is thought to be an important component of the afferent limb of the diving response. Male Sprague-Dawley rats (N = 24) were trained to swim and dive through a 5 m underwater maze. Some rats (N = 12) had bilateral sectioning of the AEN, others a Sham surgery (N = 12). Twelve rats (6 AEN cut and 6 Sham) had 24 post-surgical dive trials over 2 h to activate brainstem neurons to produce Fos, a neuronal activation marker. Remaining rats were non-diving controls. Diving animals had significantly more Fos-positive neurons than non-diving animals in the caudal pressor area, ventral medullary dorsal horn, ventral paratrigeminal nucleus, nucleus tractus solitarius, rostral ventrolateral medulla, Raphe nuclei, A5, Locus Coeruleus, and Kölliker-Fuse area. There were no significant differences in brainstem Fos labeling in rats diving with and without intact AENs. Thus, the AENs are not required for initiation of the diving response. Other nerve(s) that innervate the nose and nasal passages, and/or suprabulbar activation of brainstem neurons, may be responsible for the pattern of neuronal activation observed during repetitive trained diving in rats. These results help define the central neuronal circuitry of the mammalian diving response.

  10. Repetitive Diving in Trained Rats Still Increases Fos Production in Brainstem Neurons after Bilateral Sectioning of the Anterior Ethmoidal Nerve

    Science.gov (United States)

    McCulloch, Paul F.; Warren, Erik A.; DiNovo, Karyn M.

    2016-01-01

    This research was designed to investigate the role of the anterior ethmoidal nerve (AEN) during repetitive trained diving in rats, with specific attention to activation of afferent and efferent brainstem nuclei that are part of this reflexive response. The AEN innervates the nose and nasal passages and is thought to be an important component of the afferent limb of the diving response. Male Sprague-Dawley rats (N = 24) were trained to swim and dive through a 5 m underwater maze. Some rats (N = 12) had bilateral sectioning of the AEN, others a Sham surgery (N = 12). Twelve rats (6 AEN cut and 6 Sham) had 24 post-surgical dive trials over 2 h to activate brainstem neurons to produce Fos, a neuronal activation marker. Remaining rats were non-diving controls. Diving animals had significantly more Fos-positive neurons than non-diving animals in the caudal pressor area, ventral medullary dorsal horn, ventral paratrigeminal nucleus, nucleus tractus solitarius, rostral ventrolateral medulla, Raphe nuclei, A5, Locus Coeruleus, and Kölliker-Fuse area. There were no significant differences in brainstem Fos labeling in rats diving with and without intact AENs. Thus, the AENs are not required for initiation of the diving response. Other nerve(s) that innervate the nose and nasal passages, and/or suprabulbar activation of brainstem neurons, may be responsible for the pattern of neuronal activation observed during repetitive trained diving in rats. These results help define the central neuronal circuitry of the mammalian diving response. PMID:27148082

  11. Brainstem neurons survive the identical ischemic stress that kills higher neurons: insight to the persistent vegetative state.

    Directory of Open Access Journals (Sweden)

    C Devin Brisson

    Full Text Available Global ischemia caused by heart attack, pulmonary failure, near-drowning or traumatic brain injury often damages the higher brain but not the brainstem, leading to a 'persistent vegetative state' where the patient is awake but not aware. Approximately 30,000 U.S. patients are held captive in this condition but not a single research study has addressed how the lower brain is preferentially protected in these people. In the higher brain, ischemia elicits a profound anoxic depolarization (AD causing neuronal dysfunction and vasoconstriction within minutes. Might brainstem nuclei generate less damaging AD and so be more resilient? Here we compared resistance to acute injury induced from simulated ischemia by 'higher' hippocampal and striatal neurons versus brainstem neurons in live slices from rat and mouse. Light transmittance (LT imaging in response to 10 minutes of oxygen/glucose deprivation (OGD revealed immediate and acutely damaging AD propagating through gray matter of neocortex, hippocampus, striatum, thalamus and cerebellar cortex. In adjacent brainstem nuclei, OGD-evoked AD caused little tissue injury. Whole-cell patch recordings from hippocampal and striatal neurons under OGD revealed sudden membrane potential loss that did not recover. In contrast brainstem neurons from locus ceruleus and mesencephalic nucleus as well as from sensory and motor nuclei only slowly depolarized and then repolarized post-OGD. Two-photon microscopy confirmed non-recoverable swelling and dendritic beading of hippocampal neurons during OGD, while mesencephalic neurons in midbrain appeared uninjured. All of the above responses were mimicked by bath exposure to 100 µM ouabain which inhibits the Na+/K+ pump or to 1-10 nM palytoxin which converts the pump into an open cationic channel. Therefore during ischemia the Na+/K+ pump of higher neurons fails quickly and extensively compared to naturally resilient hypothalamic and brainstem neurons. The selective survival

  12. Musicians and Tone-Language Speakers Share Enhanced Brainstem Encoding but Not Perceptual Benefits for Musical Pitch

    Science.gov (United States)

    Bidelman, Gavin M.; Gandour, Jackson T.; Krishnan, Ananthanarayan

    2011-01-01

    Behavioral and neurophysiological transfer effects from music experience to language processing are well-established but it is currently unclear whether or not linguistic expertise (e.g., speaking a tone language) benefits music-related processing and its perception. Here, we compare brainstem responses of English-speaking musicians/non-musicians…

  13. Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S.

    2006-01-01

    We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage. (orig.)

  14. Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan)

    2006-03-15

    We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage. (orig.)

  15. Enterovirus 71 Brainstem Encephalitis and Cognitive and Motor Deficits

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-12-01

    Full Text Available Follow-up studies were conducted in 63 previously healthy children with enterovirus 71 brainstem encephalitis (49 stage II, 7 stage Ilia, and 7 stage Illb at National Cheng Kung University Hospital, Tainan, Taiwan.

  16. Brainstem variant of posterior reversible encephalopathy syndrome: A case report.

    Science.gov (United States)

    Tortora, Fabio; Caranci, Ferdinando; Belfiore, Maria Paola; Manzi, Francesca; Pagliano, Pasquale; Cirillo, Sossio

    2015-12-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological condition, generally observed in conjunction with severe and acute hypertension, that involves mainly the posterior head areas (occipital and temporal lobes) and anterior "watershed" areas. In this syndrome it is rare to observe a predominant involvement of the brainstem. We describe the clinical and radiological findings in a patient with brainstem involvement, discussing its pathophysiological features and possible differential diagnosis. © The Author(s) 2015.

  17. Brainstem cysticercose simulating cystic tumor lesion: a case report

    Directory of Open Access Journals (Sweden)

    Walter O. Arruda

    1994-09-01

    Full Text Available The authors report the case of a 37 year-old man with a solitary cysticercus cyst in the brainstem (pons successfully removed through a suboccipital craniectomy. Surgery in neurocysticercosis has been indicated in patients with hydrocephalus and/or large cystic lesions. Cystic lesions in the brainstem and spinal cord may have indication for surgery for two reasons: (1 diagnosis; and (2 treatment. Aspects related to differential diagnosis and therapeutic alternatives are discussed.

  18. Effects of multiple sclerosis brainstem lesions on sound lateralization and brainstem auditory evoked potentials.

    Science.gov (United States)

    Levine, R A; Gardner, J C; Fullerton, B C; Stufflebeam, S M; Carlisle, E W; Furst, M; Rosen, B R; Kiang, N Y

    1993-06-01

    Magnetic resonance (MR) imaging, brainstem auditory evoked potentials (BAEPs), and tests of interaural time and level discrimination were performed on sixteen subjects with multiple sclerosis (MS). Objective criteria were used to define MR lesions. Of the eleven subjects in whom no pontine lesions were detected and the one subject who had pontine lesions that did not encroach upon the auditory pathways, all had normal BAEPs and interaural level discrimination, although a few had abnormal interaural time discrimination. Of four subjects with lesions involving the pontine auditory pathway, all had both abnormal BAEPs and abnormal interaural time discrimination; one also had abnormal interaural level discrimination. Analysis of the data suggest the following: waves I and II are generated peripheral to the middle of the ventral acoustic stria (VAS); wave III is generated ipsilaterally in the region of the rostral VAS, caudal superior olivary complex (SOC) and trapezoid body (TB); and waves V and L are generated contralaterally, rostral to the SOC-TB. The region of the ipsilateral rostral SOC-TB is implicated as part of the pathway involved in the generation of waves V and L. Interaural time discrimination of both high and low frequency stimuli were affected by all brainstem lesions that encroached on auditory pathways. A unilateral lesion in the region of the LL affected interaural time discrimination for low-frequency stimuli less severely than bilateral lesions of the LL or a unilateral lesion of the VAS. The only interaural level discrimination abnormality occurred for a subject with a unilateral lesion involving the entire rostral VAS. It appears that detailed analysis of lesion locations coupled with electrophysiological and psychophysical data holds promise for testing hypotheses concerning the function of various human auditory brainstem structures.

  19. Brainstem encoding of speech and musical stimuli in congenital amusia: Evidence from Cantonese speakers

    Directory of Open Access Journals (Sweden)

    Fang eLiu

    2015-01-01

    Full Text Available Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB, and two cello tones in quiet while their frequency-following responses (FFRs to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain.

  20. Brainstem encoding of speech and musical stimuli in congenital amusia: evidence from Cantonese speakers.

    Science.gov (United States)

    Liu, Fang; Maggu, Akshay R; Lau, Joseph C Y; Wong, Patrick C M

    2014-01-01

    Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s) of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise) and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB), and two cello tones in quiet while their frequency-following responses (FFRs) to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise) and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise) than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain.

  1. Brainstem encoding of speech and musical stimuli in congenital amusia: evidence from Cantonese speakers

    Science.gov (United States)

    Liu, Fang; Maggu, Akshay R.; Lau, Joseph C. Y.; Wong, Patrick C. M.

    2015-01-01

    Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s) of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise) and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB), and two cello tones in quiet while their frequency-following responses (FFRs) to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise) and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise) than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain. PMID:25646077

  2. Migraine with brainstem aura: Why not a cortical origin?

    Science.gov (United States)

    Demarquay, Geneviève; Ducros, Anne; Montavont, Alexandra; Mauguiere, François

    2017-01-01

    Background Migraine with brainstem aura is defined as a migraine with aura including at least two of the following symptoms: dysarthria, vertigo, tinnitus, hypacusis, diplopia, ataxia and/or decreased level of consciousness. Aim The aim of this study is to review data coming from clinical observations and functional mapping that support the role of the cerebral cortex in the initiation of brainstem aura symptoms. Results Vertigo can result from a vestibular cortex dysfunction, while tinnitus and hypacusis can originate within the auditory cortex. Diplopia can reflect a parieto-occipital involvement. Dysarthria can be caused by dysfunctions located in precentral gyri. Ataxia can reflect abnormal processing of vestibular, sensory, or visual inputs by the parietal lobe. Alteration of consciousness can be caused by abnormal neural activation within specific consciousness networks that include prefrontal and posterior parietal cortices. Conclusion Any symptom of so-called brainstem aura can originate within the cortex. Based on these data, we suggest that brainstem aura could have a cortical origin. This hypothesis would explain the co-occurrence of typical and brainstem aura during attacks and would fit with the theory of cortical spreading depression. We propose that migraine with brainstem aura should be classified as a typical migraine aura.

  3. Unique Features of the Human Brainstem and Cerebellum

    Directory of Open Access Journals (Sweden)

    Joan S Baizer

    2014-04-01

    Full Text Available The cerebral cortex is greatly expanded in the human brain. There is a parallel expansion of the cerebellum, which is interconnected with the cerebral cortex. We have asked if there are accompanying changes in the organization of the precerebellar brainstem structures. We have examined the cytoarchitectonic and neurochemical organization of the human medulla and pons. We studied human cases from the Witelson Normal Brain Collection, analyzing Nissl sections and sections processed for immunohistochemistry for multiple markers including the calcium-binding proteins calbindin, calretinin and parvalbumin, nonphosphorylated neurofilament protein, and the synthetic enzyme for nitric oxide, nitric oxide synthase. We have also compared the neurochemical organization of the human brainstem to that of several other species including the chimpanzee, macaque and squirrel monkey, cat, and rodent, again using Nissl staining and immunohistochemistry. We found that there are major differences in the human brainstem, ranging from relatively subtle differences in the neurochemical organization of structures found in each of the species studied to the emergence of altogether new structures in the human brainstem. Two aspects of human cortical organization, individual differences and left-right asymmetry, are also seen in the brainstem (principal nucleus of the inferior olive and the cerebellum (the dentate nucleus. We suggest that uniquely human motor and cognitive abilities derive from changes at all levels of the central nervous system, including the cerebellum and brainstem, and not just the cerebral cortex.

  4. Musicians demonstrate experience-dependent brainstem enhancement of musical scale features within continuously gliding pitch.

    Science.gov (United States)

    Bidelman, Gavin M; Gandour, Jackson T; Krishnan, Ananthanarayan

    2011-10-10

    In contrast to language, where pitch patterns consist of continuous and curvilinear contours, musical pitch consists of relatively discrete, stair-stepped sequences of notes. Behavioral and neurophysiological studies suggest that both tone-language and music experience enhance the representation of pitch cues associated with a listener's domain of expertise, e.g., curvilinear pitch in language, discrete scale steps in music. We compared brainstem frequency-following responses (FFRs) of English-speaking musicians (musical pitch experience) and native speakers of Mandarin Chinese (linguistic pitch experience) elicited by rising and falling tonal sweeps that are exemplary of Mandarin tonal contours but uncharacteristic of the pitch patterns typically found in music. In spite of musicians' unfamiliarity with such glides, we find that their brainstem FFRs show enhancement of the stimulus where the curvilinear sweep traverses discrete notes along the diatonic musical scale. This enhancement was note specific in that it was not observed immediately preceding or following the scale tone of interest (passing note). No such enhancements were observed in Chinese listeners. These findings suggest that the musician's brainstem may be differentially tuned by long-term exposure to the pitch patterns inherent to music, extracting pitch in relation to a fixed, hierarchical scale. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. [Brainstem auditory evoked potentials and somatosensory evoked potentials in Chiari malformation].

    Science.gov (United States)

    Moncho, Dulce; Poca, María A; Minoves, Teresa; Ferré, Alejandro; Rahnama, Kimia; Sahuquillo, Juan

    2013-06-16

    Chiari malformations (CM) include a series of congenital anomalies involving the descent of the cerebellar tonsils below the foramen magnum, which may be associated with compression in the brainstem, upper spinal cord, and cranial nerves, consequently altering the responses of brainstem auditory evoked potentials (BAEP) and somatosensory evoked potentials (SSEP). However, only a small number of authors have described the indications of these tests in CM, and study groups to date have been small and heterogeneous. To review the results of BAEPs and SSEPs in published studies of patients with Chiari type 1 malformation (CM-1) or Chiari type 2 malformation (CM-2) as well as the indications of both tests in the diagnosis, treatment, and monitoring of both diseases, especially CM-1. We present a review article analyzing data from all published studies in Medline starting in 1966, located through PubMed, using combinations of the following keywords: 'Chiari malformation', 'Arnold-Chiari malformation', 'Chiari type 1 malformation', 'Arnold-Chiari type 1 malformation', 'evoked potentials', 'brainstem auditory evoked potentials' and 'somatosensory evoked potentials' as well as records of patients with CM-1 from the neurosurgery and neurophysiology departments at the Hospital Universitari Vall d'Hebron. Common findings of SSEP are a reduction in cortical amplitude from the posterior tibial nerve, a reduction or absence of cervical median nerve potential, and an increased N13-N20 interval. In BAEP, the most frequent findings are an increased I-V interval and a peripheral or cochlear auditory disturbance.

  6. Delineating function and connectivity of optokinetic hubs in the cerebellum and the brainstem.

    Science.gov (United States)

    Ruehl, Ria Maxine; Hinkel, Carolin; Bauermann, Thomas; Eulenburg, Peter Zu

    2017-12-01

    Optokinetic eye movements are crucial for keeping a stable image on the retina during movements of the head. These eye movements can be differentiated into a cortically generated response (optokinetic look nystagmus) and the highly reflexive optokinetic stare nystagmus, which is controlled by circuits in the brainstem and cerebellum. The contributions of these infratentorial networks and their functional connectivity with the cortical eye fields are still poorly understood in humans. To map ocular motor centres in the cerebellum and brainstem, we studied stare nystagmus using small-field optokinetic stimuli in the horizontal and vertical directions in 22 healthy subjects. We were able to differentiate ocular motor areas of the pontine brainstem and midbrain in vivo for the first time. Direction and velocity-dependent activations were found in the pontine brainstem (nucleus reticularis, tegmenti pontis, and paramedian pontine reticular formation), the uvula, flocculus, and cerebellar tonsils. The ocular motor vermis, on the other hand, responded to constant and accelerating velocity stimulation. Moreover, deactivation patterns depict a governing role for the cerebellar tonsils in ocular motor control. Functional connectivity results of these hubs reveal the close integration of cortico-cerebellar ocular motor and vestibular networks in humans. Adding to the cortical concept of a right-hemispheric predominance for visual-spatial processing, we found a complementary left-sided cerebellar dominance for our ocular motor task. A deeper understanding of the role of the cerebellum and especially the cerebellar tonsils for eye movement control in a clinical context seems vitally important and is now feasible with functional neuroimaging.

  7. Case Report: Encephalitis, with Brainstem Involvement, Following Checkpoint Inhibitor Therapy in Metastatic Melanoma.

    Science.gov (United States)

    Bossart, Simon; Thurneysen, Selina; Rushing, Elisabeth; Frontzek, Karl; Leske, Henning; Mihic-Probst, Daniela; Nagel, Hannes W; Mangana, Johanna; Goldinger, Simone M; Dummer, Reinhard

    2017-06-01

    Checkpoint inhibitors are increasingly being used in the treatment of malignant melanoma and other cancers. With the use of such therapies, autoimmune-mediated adverse events in the central and peripheral nervous system are likely to occur more frequently. We report a unique case of brainstem encephalitis with a sudden lethal outcome following ipilimumab and pembrolizumab therapy in a patient with malignant melanoma. The autopsy showed a diffuse nodular activation of microglia in the whole encephalon with prominent intraparenchymal and perivascular lymphocytic infiltration of the brainstem. Non-infectious brainstem encephalitis is a well-recognized subset of paraneoplastic encephalitis. Brainstem involvement is usually accompanied by a wide spectrum of signs and symptoms, which were not observed in this case. The timing of the clinical symptoms as well as the histopathological findings suggest an autoimmune-adverse event of ipilimumab and pembrolizumab administration rather than a paraneoplastic disorder. In the presence of neurological symptoms, immediate cessation of the immunotherapy and immunosuppressive therapy may lead to successful therapeutic intervention, as described in previous reports. Therefore, it is crucial that physicians are aware of the possible side effects of immunotherapies on the nervous system. Metastatic melanoma patients treated with the anti-CTLA-4 inhibitor ipilimumab have a high utilization of various types of health care services, such as inpatient hospital stays or doctor visits. There are differences across countries regarding patterns of health care utilization and economic burden of the disease. Health care services are used more frequently after patients experience progression of their disease. The study highlights that better therapies leading to durable response in patients with metastatic melanoma have the potential to decrease health care costs and patient burden in terms of hospitalizations and other health care services.

  8. Brainstem tolerance to conformal radiotherapy of skull base tumors

    International Nuclear Information System (INIS)

    Debus, J.; Hug, E.B.; Munzenrider, J.E.; Liebsch, N.J.; O'Farrell, D.; Efird, J.; Daly, W.; Suit, H.D.

    1996-01-01

    Purpose/Objective: Brainstem tolerance to inhomogenous radiation doses applied by modern conformal radiotherapy has not yet been examined. The aim of this study was to analyse the incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Materials and Methods: Between 1974 and 1995, 367 patients with chordomas (n=195) and chondrosarcomas (n=172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. All patients had previously undergone biopsy, subtotal or total tumor removal. 104 patients had two or more surgical procedures before radiotherapy. Following 3D treatment planning with delineation of target volumes and critical non-target structures, dose distributions and dose volume histograms were calculated [at the time of treatment delivery]. Radiotherapy was given once a day, 1.8 Gy or CGE (Cobalt Gy Equivalent: Proton Gy X 1.1) per fraction, 5 fractions per week, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Dose distributions were developed to limit dose to brainstem surface and center; current plans limit dose to surface and center to ≤64 CGE and ≤53 CGE, respectively. Brainstem toxicity was scored according to the RTOG grading system. Results: Follow-up ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem symptoms, attributable to the treatment, developed in 17 of 282 patients with local tumor control (6.0%), resulting in death of three patients. The mean time to onset of symptoms was 17 months (range: 4.5 to 177 months). These symptoms appeared in 89.5% within 3 years. Grading of the brainstem toxicity is listed in table 1. Actuarial rates of 5 and 10 year toxicity free survival were 87% and 82% respectively. Increased risk of brainstem toxicity was significantly associated with maximum brainstem dose

  9. Cross-domain effects of music and language experience on the representation of pitch in the human auditory brainstem.

    Science.gov (United States)

    Bidelman, Gavin M; Gandour, Jackson T; Krishnan, Ananthanarayan

    2011-02-01

    Neural encoding of pitch in the auditory brainstem is known to be shaped by long-term experience with language or music, implying that early sensory processing is subject to experience-dependent neural plasticity. In language, pitch patterns consist of sequences of continuous, curvilinear contours; in music, pitch patterns consist of relatively discrete, stair-stepped sequences of notes. The primary aim was to determine the influence of domain-specific experience (language vs. music) on the encoding of pitch in the brainstem. Frequency-following responses were recorded from the brainstem in native Chinese, English amateur musicians, and English nonmusicians in response to iterated rippled noise homologues of a musical pitch interval (major third; M3) and a lexical tone (Mandarin tone 2; T2) from the music and language domains, respectively. Pitch-tracking accuracy (whole contour) and pitch strength (50 msec sections) were computed from the brainstem responses using autocorrelation algorithms. Pitch-tracking accuracy was higher in the Chinese and musicians than in the nonmusicians across domains. Pitch strength was more robust across sections in musicians than in nonmusicians regardless of domain. In contrast, the Chinese showed larger pitch strength, relative to nonmusicians, only in those sections of T2 with rapid changes in pitch. Interestingly, musicians exhibited greater pitch strength than the Chinese in one section of M3, corresponding to the onset of the second musical note, and two sections within T2, corresponding to a note along the diatonic musical scale. We infer that experience-dependent plasticity of brainstem responses is shaped by the relative saliency of acoustic dimensions underlying the pitch patterns associated with a particular domain.

  10. Reductions in cortical alpha activity, enhancements in neural responses and impaired gap detection caused by sodium salicylate in awake guinea pigs.

    Science.gov (United States)

    Berger, Joel I; Coomber, Ben; Wallace, Mark N; Palmer, Alan R

    2017-02-01

    Tinnitus chronically affects between 10-15% of the population but, despite its prevalence, the underlying mechanisms are still not properly understood. One experimental model involves administration of high doses of sodium salicylate, as this is known to reliably induce tinnitus in both humans and animals. Guinea pigs were implanted with chronic electrocorticography (ECoG) electrode arrays, with silver-ball electrodes placed on the dura over left and right auditory cortex. Two more electrodes were positioned over the cerebellum to monitor auditory brainstem responses (ABRs). We recorded resting-state and auditory evoked neural activity from awake animals before and 2 h following salicylate administration (350 mg/kg; i.p.). Large increases in click-evoked responses (> 100%) were evident across the whole auditory cortex, despite significant reductions in wave I ABR amplitudes (in response to 20 kHz tones), which are indicative of auditory nerve activity. In the same animals, significant decreases in 6-10 Hz spontaneous oscillations (alpha waves) were evident over dorsocaudal auditory cortex. We were also able to demonstrate for the first time that cortical evoked potentials can be inhibited by a preceding gap in background noise [gap-induced pre-pulse inhibition (PPI)], in a similar fashion to the gap-induced inhibition of the acoustic startle reflex that is used as a behavioural test for tinnitus. Furthermore, 2 h following salicylate administration, we observed significant deficits in PPI of cortical responses that were closely aligned with significant deficits in behavioural responses to the same stimuli. Together, these data are suggestive of neural correlates of tinnitus and oversensitivity to sound (hyperacusis). © 2016 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  11. Convergent input from brainstem coincidence detectors onto delay-sensitive neurons in the inferior colliculus.

    Science.gov (United States)

    McAlpine, D; Jiang, D; Shackleton, T M; Palmer, A R

    1998-08-01

    Responses of low-frequency neurons in the inferior colliculus (IC) of anesthetized guinea pigs were studied with binaural beats to assess their mean best interaural phase (BP) to a range of stimulating frequencies. Phase plots (stimulating frequency vs BP) were produced, from which measures of characteristic delay (CD) and characteristic phase (CP) for each neuron were obtained. The CD provides an estimate of the difference in travel time from each ear to coincidence-detector neurons in the brainstem. The CP indicates the mechanism underpinning the coincidence detector responses. A linear phase plot indicates a single, constant delay between the coincidence-detector inputs from the two ears. In more than half (54 of 90) of the neurons, the phase plot was not linear. We hypothesized that neurons with nonlinear phase plots received convergent input from brainstem coincidence detectors with different CDs. Presentation of a second tone with a fixed, unfavorable delay suppressed the response of one input, linearizing the phase plot and revealing other inputs to be relatively simple coincidence detectors. For some neurons with highly complex phase plots, the suppressor tone altered BP values, but did not resolve the nature of the inputs. For neurons with linear phase plots, the suppressor tone either completely abolished their responses or reduced their discharge rate with no change in BP. By selectively suppressing inputs with a second tone, we are able to reveal the nature of underlying binaural inputs to IC neurons, confirming the hypothesis that the complex phase plots of many IC neurons are a result of convergence from simple brainstem coincidence detectors.

  12. Musical training heightens auditory brainstem function during sensitive periods in development

    Directory of Open Access Journals (Sweden)

    Erika eSkoe

    2013-09-01

    Full Text Available Experience has a profound influence on how sound is processed in the brain. Yet little is known about how enriched experiences interact with developmental processes to shape neural processing of sound. We examine this question as part of a large cross-sectional study of auditory brainstem development involving more than 700 participants, 213 of whom were classified as musicians. We hypothesized that experience-dependent processes piggyback on developmental processes, resulting in a waxing-and-waning effect of experience that tracks with the undulating developmental baseline. This hypothesis led to the prediction that experience-dependent plasticity would be amplified during periods when developmental changes are underway (i.e., early and later in life and that the peak in experience-dependent plasticity would coincide with the developmental apex for each subcomponent of the auditory brainstem response. Consistent with our predictions, we reveal that musicians have heightened response features at distinctive times in the life span that coincide with periods of developmental change and climax. The effect of musicianship is also quite specific: we find that only select components of auditory brainstem activity are affected, with musicians having heightened function for onset latency, high frequency phase-locking, and response consistency, and with little effect observed for other measures, including lower frequency phase-locking and non-stimulus-related activity. By showing that musicianship imparts a neural signature that is especially evident during childhood and old age, our findings reinforce the idea that the nervous system’s response to sound is chiseled by how a person interacts with his specific auditory environment, with the effect of the environment wielding its greatest influence during certain privileged windows of development.

  13. Clinical and radiological features of hypertensive brainstem encephalopathy

    Directory of Open Access Journals (Sweden)

    Xiao-qiu LI

    2015-07-01

    Full Text Available Objective To discuss the diagnosis and treatment of hypertensive brainstem encephalopathy. Methods  The clinical and imaging data of 3 cases of hypertensive brainstem encephalopathy were summarized and analyzed for the purpose of improving the acumen in diagnosis and treatment. Results All the 3 patients showed relatively mild clinical symptoms, and they were misdiagnosed in different degrees during the treatment, but their clinical symptoms were improved by rapid and effective antihypertensive therapy. Cerebral CT and MRI scans revealed extensive abnormal signals in brain stem, with or without supratentorial lesions and brain stem hemorrhage. The lesions as revealed by imaging were improved significantly after treatment. Conclusions Clinical-radiographic dissociation is the classic feature of hypertensive brainstem encephalopathy. The clinical symptoms and lesions as shown by imaging could be improved after active treatment. DOI: 10.11855/j.issn.0577-7402.2015.06.03

  14. Medical Physics Residency Consortium: collaborative endeavors to meet the ABR 2014 certification requirements

    Science.gov (United States)

    Parker, Brent C.; Duhon, John; Yang, Claus C.; Wu, H. Terry; Hogstrom, Kenneth R.

    2014-01-01

    In 2009, Mary Bird Perkins Cancer Center (MBPCC) established a Radiation Oncology Physics Residency Program to provide opportunities for medical physics residency training to MS and PhD graduates of the CAMPEP‐accredited Louisiana State University (LSU)‐MBPCC Medical Physics Graduate Program. The LSU‐MBPCC Program graduates approximately six students yearly, which equates to a need for up to twelve residency positions in a two‐year program. To address this need for residency positions, MBPCC has expanded its Program by developing a Consortium consisting of partnerships with medical physics groups located at other nearby clinical institutions. The consortium model offers the residents exposure to a broader range of procedures, technology, and faculty than available at the individual institutions. The Consortium institutions have shown a great deal of support from their medical physics groups and administrations in developing these partnerships. Details of these partnerships are specified within affiliation agreements between MBPCC and each participating institution. All partner sites began resident training in 2011. The Consortium is a network of for‐profit, nonprofit, academic, community, and private entities. We feel that these types of collaborative endeavors will be required nationally to reach the number of residency positions needed to meet the 2014 ABR certification requirements and to maintain graduate medical physics training programs. PACS numbers: 01.40.Fk, 01.40.gb PMID:24710434

  15. Analysis of abrB Expression during the Infectious Cycle of Bacillus thuringiensis Reveals Population Heterogeneity

    Directory of Open Access Journals (Sweden)

    Samia Ben Rejeb

    2017-12-01

    Full Text Available Using the model host/pathogen pair Galleria mellonella/Bacillus thuringiensis, we have shown that these bacteria could kill their insect host, survive in its cadaver and form spores by sequentially activating virulence, necrotrophism and sporulation genes. However, the population isolated from the cadavers was heterogeneous, including non-sporulating cells in an unknown physiological state. To characterize these bacteria, we used a transcriptional fusion between the promoter of a gene expressed during early exponential growth (abrB and a reporter gene encoding a destabilized version of GFP, in combination with a fluorescent reporter of the necrotrophic state. The composition of the bacterial population during infection was then analyzed by flow cytometry. We showed that the PabrB promoter was activated in the population that had turned on the necrotrophic reporter, suggesting a re-entry into vegetative growth. Strikingly, the cells that did not go through the necrotrophic state did not activate the PabrB promoter and appear as a dormant subpopulation. We propose a new model describing the B. thuringiensis cell types during infection.

  16. Medical Physics Residency Consortium: collaborative endeavors to meet the ABR 2014 certification requirements.

    Science.gov (United States)

    Parker, Brent C; Duhon, John; Yang, Claus C; Wu, H Terry; Hogstrom, Kenneth R; Gibbons, John P

    2014-03-06

    In 2009, Mary Bird Perkins Cancer Center (MBPCC) established a Radiation Oncology Physics Residency Program to provide opportunities for medical physics residency training to MS and PhD graduates of the CAMPEP-accredited Louisiana State University (LSU)-MBPCC Medical Physics Graduate Program. The LSU-MBPCC Program graduates approximately six students yearly, which equates to a need for up to twelve residency positions in a two-year program. To address this need for residency positions, MBPCC has expanded its Program by developing a Consortium consisting of partnerships with medical physics groups located at other nearby clinical institutions. The consortium model offers the residents exposure to a broader range of procedures, technology, and faculty than available at the individual institutions. The Consortium institutions have shown a great deal of support from their medical physics groups and administrations in developing these partnerships. Details of these partnerships are specified within affiliation agreements between MBPCC and each participating institution. All partner sites began resident training in 2011. The Consortium is a network of for-profit, nonprofit, academic, community, and private entities. We feel that these types of collaborative endeavors will be required nationally to reach the number of residency positions needed to meet the 2014 ABR certification requirements and to maintain graduate medical physics training programs.

  17. Ethnobotany, chemical constituents and biological activities of the flowers of Hydnora abyssinica A.Br. (Hydnoraceae).

    Science.gov (United States)

    Al-Fatimi, M; Ali, N A A; Kilian, N; Franke, K; Arnold, N; Kuhnt, C; Schmidt, J; Lindequist, U

    2016-04-01

    Hydnora abyssinica A.Br. (Hydnoraceae), a holoparasitic herb, is for the first time recorded for Abyan governorate of South Yemen. Flowers of this species were studied for their ethnobotanical, biological and chemical properties for the first time. In South Yemen, they are traditionally used as wild food and to cure stomach diseases, gastric ulcer and cancer. Phytochemical analysis of the extracts showed the presence of terpenes, tannins, phenols, and flavonoids. The volatile components of the air-dried powdered flowers were identified using a static headspace GC/MS analysis as acetic acid, ethyl acetate, sabinene, α-terpinene, (+)-D-limonene and γ-terpinene. These volatile compounds that characterize the odor and taste of the flowers were detected for the first time in a species of the family Hydnoraceae. The flowers were extracted by n-hexane, dichlormethane, ethyl acetate, ethanol, methanol and water. With exception of the water extract all extracts demonstrated activities against Gram-positive bacteria as well as remarkable radical scavenging activities in DPPH assay. Ethyl acetate, methanol and water extracts exhibited good antifungal activities. The cytotoxic activity of the extracts against FL cells, measured in neutral red assay, was only weak (IC50 > 500 μg/mL). The results justify the traditional use of the flowers of Hydnora abyssinica in South Yemen.

  18. Hydraulic characteristics simulation of an innovative self-agitation anaerobic baffled reactor (SA-ABR).

    Science.gov (United States)

    Qi, Wei-Kang; Hojo, Toshimasa; Li, Yu-You

    2013-05-01

    An investigation was conducted on a self-agitation anaerobic baffled reactor (SA-ABR) with agitation caused solely by the release of stored gas. The compound in the reactor is mixed without the use of any mechanical equipment and electricity. The computational fluid dynamics (CFD) simulation used to provide details of the flow pattern and information about the agitation process and a solid basis for design and optimization purposes. Every self-agitation cycle could be separated into the pressure energy storage process, the exergonic process and the buffer stage. The reactor is regarded as the combination of continuous stirred tank reactor and a small plug flow reactor. The liquid level and diffusion varies widely depending on the length of the U-tube. The compound transition phenomenon in the 1st chamber mainly occurs during the energy exergonic process and buffer stage. The fluid-diffusion in the 3rd and 4th chambers mainly happens after the buffer period. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  19. Adaptive hypofractionated gamma knife radiosurgery for a large brainstem metastasis

    DEFF Research Database (Denmark)

    Sinclair, Georges; Bartek, Jiri; Martin, Heather

    2016-01-01

    BACKGROUND: To demonstrate how adaptive hypofractionated radiosurgery by gamma knife (GK) can be successfully utilized to treat a large brainstem metastasis - a novel approach to a challenging clinical situation. CASE DESCRIPTION: A 42-year-old woman, diagnosed with metastatic nonsmall cell lung...... in October 2013 revealed a growing brainstem lesion of 26 mm. Linear accelerator-based radiotherapy and microsurgery were judged contraindicated, why the decision was made to treat the patient with three separate radiosurgical sessions during the course of 1 week, with an 18% tumor volume reduction...

  20. Two-phase anaerobic digestion for biogas production from dairy effluent—CSTR and ABR in series

    DEFF Research Database (Denmark)

    Jürgensen, L.; Ehimen, E. A.; Born, J.

    2016-01-01

    Anaerobic digestion of low-strength dairy waste water has been used for the production of biogas. A two-phase pilot scale process had been established within 90 d using a 1 m3continuous stirred tank reactor (CSTR) and a 200 l anaerobic baffled reactor (ABR) in series. The system was fed at constant...... retention time of 1.6 d and with changing feed strengths resulting in various organic loading rates between 1.25-4.50 g/(l d). The average COD removal was 82% with a biogas yield of 0.26 l/gCOD. The combination of CSTR and ABR overcame the disadvantages of both reactor types. By further optimization...... the chosen system is able to replace conventional waste water treatment system used nowadays....

  1. The startup performance and microbial distribution of an anaerobic baffled reactor (ABR) treating medium-strength synthetic industrial wastewater.

    Science.gov (United States)

    Jiang, Hao; Nie, Hong; Ding, Jiangtao; Stinner, Walter; Sun, Kaixuan; Zhou, Hongjun

    2018-01-02

    In this study, an anaerobic baffled reactor (ABR) with seven chambers was applied to treat medium-strength synthetic industrial wastewater (MSIW). The performance of startup and shock test on treating MSIW was investigated. During the acclimation process, the chemical oxygen demand (COD) of MSIW gradually increased from 0 to 2,000 mg L -1 , and the COD removal finally reached 90%. At shock test, the feeding COD concentration increased by one-fifth and the reactor adapted very well with a COD removal of 82%. In a stable state, Comamonas, Smithella, Syntrophomonas and Pseudomonas were the main populations of bacteria, while the predominant methanogen was Methanobacterium. The results of chemical and microbiological analysis indicated the significant advantages of ABR, including buffering shocks, separating stages with matching microorganisms and promoting syntrophism. Meanwhile, the strategies for acclimation and operation were of great importance. Further work can test reactor performance in the treatment of actual industrial wastewater.

  2. Difficulties experienced in implementing the ABR travelling wave velocity (Delta V) technique with two commercially available systems.

    Science.gov (United States)

    Munro, K J; Smith, R; Thornton, A R

    1995-02-01

    The ABR Delta V technique involves measuring the difference in latency of the wave V click-evoked ABR in the presence of ipsilateral high-pass noise filtered at 1.42 kHz and at 5.68 kHz. It has been reported that a small latency difference between the two conditions is suggestive of Ménière's disease. The aim of this study was to establish normative data for two commercially available systems. The latency differences obtained in the present study are considerably smaller than those previously reported in the literature. Other problems, including difficulty in identifying wave V in the masked conditions, prevent us from currently using this test technique. There are a number of technical problems which may account for some of the problems experienced when implementing the Delta V technique with commercial equipment and there is at least the possibility that the problems may be overcome in the future.

  3. Pax3 expression enhances PDGF-B-induced brainstem gliomagenesis and characterizes a subset of brainstem glioma.

    Science.gov (United States)

    Misuraca, Katherine L; Barton, Kelly L; Chung, Alexander; Diaz, Alexander K; Conway, Simon J; Corcoran, David L; Baker, Suzanne J; Becher, Oren J

    2014-10-21

    High-grade Brainstem Glioma (BSG), also known as Diffuse Intrinsic Pontine Glioma (DIPG), is an incurable pediatric brain cancer. Increasing evidence supports the existence of regional differences in gliomagenesis such that BSG is considered a distinct disease from glioma of the cerebral cortex (CG). In an effort to elucidate unique characteristics of BSG, we conducted expression analysis of mouse PDGF-B-driven BSG and CG initiated in Nestin progenitor cells and identified a short list of expression changes specific to the brainstem gliomagenesis process, including abnormal upregulation of paired box 3 (Pax3). In the neonatal mouse brain, Pax3 expression marks a subset of brainstem progenitor cells, while it is absent from the cerebral cortex, mirroring its regional expression in glioma. Ectopic expression of Pax3 in normal brainstem progenitors in vitro shows that Pax3 inhibits apoptosis. Pax3-induced inhibition of apoptosis is p53-dependent, however, and in the absence of p53, Pax3 promotes proliferation of brainstem progenitors. In vivo, Pax3 enhances PDGF-B-driven gliomagenesis by shortening tumor latency and increasing tumor penetrance and grade, in a region-specific manner, while loss of Pax3 function extends survival of PDGF-B-driven;p53-deficient BSG-bearing mice by 33%. Importantly, Pax3 is regionally expressed in human glioma as well, with high PAX3 mRNA characterizing 40% of human BSG, revealing a subset of tumors that significantly associates with PDGFRA alterations, amplifications of cell cycle regulatory genes, and is exclusive of ACVR1 mutations. Collectively, these data suggest that regional Pax3 expression not only marks a novel subset of BSG but also contributes to PDGF-B-induced brainstem gliomagenesis.

  4. Localization of the brainstem GABAergic neurons controlling paradoxical (REM sleep.

    Directory of Open Access Journals (Sweden)

    Emilie Sapin

    Full Text Available Paradoxical sleep (PS is a state characterized by cortical activation, rapid eye movements and muscle atonia. Fifty years after its discovery, the neuronal network responsible for the genesis of PS has been only partially identified. We recently proposed that GABAergic neurons would have a pivotal role in that network. To localize these GABAergic neurons, we combined immunohistochemical detection of Fos with non-radioactive in situ hybridization of GAD67 mRNA (GABA synthesis enzyme in control rats, rats deprived of PS for 72 h and rats allowed to recover after such deprivation. Here we show that GABAergic neurons gating PS (PS-off neurons are principally located in the ventrolateral periaqueductal gray (vlPAG and the dorsal part of the deep mesencephalic reticular nucleus immediately ventral to it (dDpMe. Furthermore, iontophoretic application of muscimol for 20 min in this area in head-restrained rats induced a strong and significant increase in PS quantities compared to saline. In addition, we found a large number of GABAergic PS-on neurons in the vlPAG/dDPMe region and the medullary reticular nuclei known to generate muscle atonia during PS. Finally, we showed that PS-on neurons triggering PS localized in the SLD are not GABAergic. Altogether, our results indicate that multiple populations of PS-on GABAergic neurons are distributed in the brainstem while only one population of PS-off GABAergic neurons localized in the vlPAG/dDpMe region exist. From these results, we propose a revised model for PS control in which GABAergic PS-on and PS-off neurons localized in the vlPAG/dDPMe region play leading roles.

  5. Diffuse and focal presentations of brainstem tumors in children: the images and the prognostic value

    International Nuclear Information System (INIS)

    Menor, F.; Canete, A.; Romero, M. J.; Trilles, L.; Carvajal, E.; Marti-Bonmati, L.

    2000-01-01

    To determine whether the presentation of brainstem tumors as diffuse or focal lesions showed any prognostic value in children. A retrospective review was carried out of the neuroradiological findings in 43 children with brainstem tumors, all of whom underwent computed tomography (CT) and 31 of whom underwent magnetic resonance (MR). The diffuse tumors (n=20) were all located in the pons, spreading to mesencephalon in 6 cases and to medulla oblongata in 1, and exhibiting exophytic growth, preferentially to the prepontine cistern. They presented homogeneous low attenuation in CT (90%) and decrease/increased signal intensity in T1/T2-weighted MR images (91.6%). Contrast uptake was observed in 20% of cases, with agreement between CT and MR. The patients showed a good initial response to treatment (70%), a high rate of relapse (80%) and a 5-year survival of 12%. The focal tumors were located in the pons (11 cases, spreading to the medulla oblongata in 2), mesencephalon (11 cases, 9 tectal and 2 peduncular) and medulla oblongata (1 case), and exhibited exophytic growth predominantly to the pontocerebellar junction and to the cerebellar peduncles. They showed a certain tendency toward heterogeneity (21.7%), toward isoattenuation in CT (47.8%) and isointensity in T1-weighted MR images (26.3%). CT showed a rate of tumor uptake of 26%, while the rate of contrast iptake was 58% MR. Fifty percent of these lesions responded well to therapy, with a recurrence rate of 28% and 4-year survival of 63%. Neuroimaging helps to define two basic patterns in brainstem tumors that play a role in prognosis. The diffuse tumor, which characteristically shows a good initial response to therapy, has a worse prognosis, probably reflecting its histological aggressiveness. (Author) 21 refs

  6. Sensitization of trigeminal brainstem pathways in a model for tear deficient dry eye.

    Science.gov (United States)

    Rahman, Mostafeezur; Okamoto, Keiichiro; Thompson, Randall; Katagiri, Ayano; Bereiter, David A

    2015-05-01

    Chronic dry eye disease (DE) is associated with an unstable tear film and symptoms of ocular discomfort. The characteristics of symptoms suggest a key role for central neural processing; however, little is known about central neuroplasticity and DE. We used a model for tear deficient DE and assessed effects on eye blink behavior, orbicularis oculi muscle activity (OOemg), and trigeminal brainstem neural activity in male rats. Ocular-responsive neurons were recorded at the interpolaris/caudalis transition (Vi/Vc) and Vc/upper cervical cord (Vc/C1) regions under isoflurane, whereas OOemg activity was recorded under urethane. Spontaneous tear volume was reduced by ∼50% at 14 days after exorbital gland removal. Hypertonic saline-evoked eye blink behavior in awake rats was enhanced throughout the 14 days after surgery. Saline-evoked neural activity at the Vi/Vc transition and in superficial and deep laminae at the Vc/C1 region was greatly enhanced in DE rats. Neurons from DE rats classified as wide dynamic range displayed enlarged convergent periorbital receptive fields consistent with central sensitization. Saline-evoked OOemg activity was markedly enhanced in DE rats compared with controls. Synaptic blockade at the Vi/Vc transition or the Vc/C1 region greatly reduced hypertonic saline-evoked OOemg activity in DE and sham rats. These results indicated that persistent tear deficiency caused sensitization of ocular-responsive neurons at multiple regions of the caudal trigeminal brainstem and enhanced OOemg activity. Central sensitization of ocular-related brainstem circuits is a significant factor in DE and likely contributes to the apparent weak correlation between peripheral signs of tear dysfunction and symptoms of irritation.

  7. Gamma knife radiosurgery for brainstem arteriovenous malformations: preliminary results.

    Science.gov (United States)

    Massager, N; Régis, J; Kondziolka, D; Njee, T; Levivier, M

    2000-12-01

    This study was undertaken to assess the efficacy and safety of gamma knife radiosurgery (GKS) for the treatment of arteriovenous malformations (AVMs) located within the brainstem. The results of GKS performed in 87 patients with brainstem AVMs at two centers with experienced physicians are reviewed. The mean patient age was 37 years and the population included 19 children. The male/female ratio was 56:31. The malformation was located in the upper brainstem in 52 patients. Seventy-four percent of the patients had suffered a hemorrhage before GKS. For 70% of the patients no other treatment had been proposed before GKS. The mean AVM volume was 1.3 cm3. The lesions were treated with one to eight isocenters, with a margin dose ranging between 11.5 Gy and 30 Gy. The mean clinical follow-up period was 3.2 years. Ninety-five percent of the patients improved or remained neurologically stable. Rebleeding occurred in three patients at 3, 6, and 16 months, respectively, after GKS. Two patients in whom rebleeding occured recovered, and one died. The AVM obliteration rate was 63% at 2 years and 73% at 3 years after GKS. A second GKS was performed in six patients in whom only partial obliteration was demonstrated on angiography 3 years after the first procedure. Gamma knife radiosurgery may be a valuable first-choice therapy for the treatment of AVMs located within the brainstem.

  8. Intraparenchymal papillary meningioma of brainstem: case report and literature review

    Directory of Open Access Journals (Sweden)

    Jiang Xiao-Bing

    2012-01-01

    Full Text Available Abstract Both intraparenchymal papillary meningioma and papillary meningioma with cyst formation of brainstem have never been reported. The authors present an extremely rare case of patient with intraparenchymal papillary meningioma of brainstem. A 23-year-old Chinese male presented with a 4-month history of progressive left upper limb and facial nerve palsy. Magnetic resonance imaging revealed a cystic-solid, heterogeneously enhancing mass in pons and right cerebral peduncle with no dural attachment. The tumor was totally removed via subtemporal approach. During surgery, the lesion was found to be completely intraparenchymal. Histological and immunohistochemical examinations were compatible with the diagnosis of papillary meningioma. The lesion recurred nine months after primary surgery, a second surgery followed by radiotherapy was performed. Till to now (nearly 2 years after the treatment, the patient is tumor free survival. Intraparenchymal meningioma of brainstem with cystic formation is very rare, however, it should be considered as a differential diagnosis of a brainstem neoplasm. The present case strongly recommended that postoperative radiotherapy was essential for the patients with papillary meningiomas.

  9. Stance disturbance in multiple sclerosis: brainstem lesions and posturographic assessment

    Directory of Open Access Journals (Sweden)

    Peter Schalek

    2012-01-01

    Full Text Available

    Background. Balance disorders are commonly evidenced during the course of multiple sclerosis (MS. The aim of this study is to report characteristics of MS patient stance control disorders, measured by means of posturography and related to the brainstem lesions.

    Methods. Thirty-eight patients affected by MS, mildly to moderately disable according to Kurtzke’s Expanded Disability Status Scale, underwent a complete clinical neurological and vestibular evaluation and brain MRI scanning. All patients were then tested on a static posturography platform (Tetrax, Israel in four conditions: eyes open and closed standing on a firm surface and on a foam pad.

    Results. Clinical and/or MRI evidence of brainstem involvement was observed in 55.3 % of patients. When brainstem lesion was detected, Fourier analysis showed a typical pattern characterized by inversion of the  0- 0.1 Hz and  0.1 - 0.25 Hz. frequency bands.

    Conclusions. MS leads to pervasive postural disturbances in the majority of subjects, including the visuo-vestibular loops and proprioception involving vestibulo-spinal pathways in at least 55.3 % of patients. Our results may also suggest the presence of Fourier inversion in patients with brainstem lesions.


  10. Endocannabinoids in the brainstem modulate dural trigeminovascular nociceptive traffic via CB1 and "triptan" receptors: implications in migraine.

    Science.gov (United States)

    Akerman, Simon; Holland, Philip R; Lasalandra, Michele P; Goadsby, Peter J

    2013-09-11

    Activation and sensitization of trigeminovascular nociceptive pathways is believed to contribute to the neural substrate of the severe and throbbing nature of pain in migraine. Endocannabinoids, as well as being physiologically analgesic, are known to inhibit dural trigeminovascular nociceptive responses. They are also involved in the descending modulation of cutaneous-evoked C-fiber spinal nociceptive responses from the brainstem. The purpose of this study was to determine whether endocannabinoids are involved in the descending modulation of dural and/or cutaneous facial trigeminovascular nociceptive responses, from the brainstem ventrolateral periaqueductal gray (vlPAG). CB1 receptor activation in the vlPAG attenuated dural-evoked Aδ-fiber neurons (maximally by 19%) and basal spontaneous activity (maximally by 33%) in the rat trigeminocervical complex, but there was no effect on cutaneous facial receptive field responses. This inhibitory vlPAG-mediated modulation was inhibited by specific CB1 receptor antagonism, given via the vlPAG, and with a 5-HT1B/1D receptor antagonist, given either locally in the vlPAG or systemically. These findings demonstrate for the first time that brainstem endocannabinoids provide descending modulation of both basal trigeminovascular neuronal tone and Aδ-fiber dural-nociceptive responses, which differs from the way the brainstem modulates spinal nociceptive transmission. Furthermore, our data demonstrate a novel interaction between serotonergic and endocannabinoid systems in the processing of somatosensory nociceptive information, suggesting that some of the therapeutic action of triptans may be via endocannabinoid containing neurons in the vlPAG.

  11. Repetitive Diving in Trained Rats Still Increases Fos Production in Brainstem Neurons after Bilateral Sectioning of the Anterior Ethmoidal Nerve

    Directory of Open Access Journals (Sweden)

    Paul F Mcculloch

    2016-04-01

    Full Text Available This research was designed to investigate the role of the anterior ethmoidal nerve (AEN during repetitive trained diving in rats, with specific attention to activation of afferent and efferent brainstem nuclei that are part of this reflexive response. The AEN innervates the nose and nasal passages and is thought to be an important component of the afferent limb of the diving response. Male Sprague-Dawley rats (N=24 were trained to swim and dive through a 5 m underwater maze. Some rats (N=12 had bilateral sectioning of the AEN, others a Sham surgery (N=12. Twelve rats (6 AEN cut and 6 Sham had 24 post-surgical dive trials over 2 hrs to activate brainstem neurons to produce Fos, a neuronal activation marker. Remaining rats were non-diving controls. Diving animals had significantly more Fos-positive neurons than non-diving animals in the caudal pressor area, ventral medullary dorsal horn, ventral paratrigeminal nucleus, nucleus tractus solitarius, rostral ventrolateral medulla, Raphe nuclei, A5, Locus Coeruleus, and Kölliker-Fuse area. There were no significant differences in brainstem Fos labeling in rats diving with and without intact AENs. Thus the AENs are not required for initiation of the diving response. Other nerve(s that innervate the nose and nasal passages, and/or suprabulbar activation of brainstem neurons, may be responsible for the pattern of neuronal activation observed during repetitive trained diving in rats. These results help define the central neuronal circuitry of the mammalian diving response.

  12. SU-E-E-02: An Excel-Based Study Tool for ABR-Style Exams

    Energy Technology Data Exchange (ETDEWEB)

    Cline, K; Stanley, D; Defoor, D; Stathakis, S; Gutierrez, A; Papanikolaou, N; Kirby, N [University of Texas Health Science Center at San Antonio, Cancer Therapy and Research Center, San Antonio, TX (United States)

    2015-06-15

    Purpose: As the landscape of learning and testing shifts toward a computer-based environment, a replacement for paper-based methods of studying is desirable. Using Microsoft Excel, a study tool was developed that allows the user to populate multiple-choice questions and then generate an interactive quiz session to answer them. Methods: The code for the tool was written using Microsoft Excel Visual Basic for Applications with the intent that this tool could be implemented by any institution with Excel. The base tool is a template with a setup macro, which builds out the structure based on user’s input. Once the framework is built, the user can input sets of multiple-choice questions, answer choices, and even add figures. The tool can be run in random-question or sequential-question mode for single or multiple courses of study. The interactive session allows the user to select answer choices and immediate feedback is provided. Once the user is finished studying, the tool records the day’s progress by reporting progress statistics useful for trending. Results: Six doctoral students at UTHSCSA have used this tool for the past two months to study for their qualifying exam, which is similar in format and content to the American Board of Radiology (ABR) Therapeutic Part II exam. The students collaborated to create a repository of questions, met weekly to go over these questions, and then used the tool to prepare for their exam. Conclusion: The study tool has provided an effective and efficient way for students to collaborate and be held accountable for exam preparation. The ease of use and familiarity of Excel are important factors for the tool’s use. There are software packages to create similar question banks, but this study tool has no additional cost for those that already have Excel. The study tool will be made openly available.

  13. SU-E-E-02: An Excel-Based Study Tool for ABR-Style Exams

    International Nuclear Information System (INIS)

    Cline, K; Stanley, D; Defoor, D; Stathakis, S; Gutierrez, A; Papanikolaou, N; Kirby, N

    2015-01-01

    Purpose: As the landscape of learning and testing shifts toward a computer-based environment, a replacement for paper-based methods of studying is desirable. Using Microsoft Excel, a study tool was developed that allows the user to populate multiple-choice questions and then generate an interactive quiz session to answer them. Methods: The code for the tool was written using Microsoft Excel Visual Basic for Applications with the intent that this tool could be implemented by any institution with Excel. The base tool is a template with a setup macro, which builds out the structure based on user’s input. Once the framework is built, the user can input sets of multiple-choice questions, answer choices, and even add figures. The tool can be run in random-question or sequential-question mode for single or multiple courses of study. The interactive session allows the user to select answer choices and immediate feedback is provided. Once the user is finished studying, the tool records the day’s progress by reporting progress statistics useful for trending. Results: Six doctoral students at UTHSCSA have used this tool for the past two months to study for their qualifying exam, which is similar in format and content to the American Board of Radiology (ABR) Therapeutic Part II exam. The students collaborated to create a repository of questions, met weekly to go over these questions, and then used the tool to prepare for their exam. Conclusion: The study tool has provided an effective and efficient way for students to collaborate and be held accountable for exam preparation. The ease of use and familiarity of Excel are important factors for the tool’s use. There are software packages to create similar question banks, but this study tool has no additional cost for those that already have Excel. The study tool will be made openly available

  14. Effects of reverberation on brainstem representation of speech in musicians and non-musicians.

    Science.gov (United States)

    Bidelman, Gavin M; Krishnan, Ananthanarayan

    2010-10-08

    Perceptual and neurophysiological enhancements in linguistic processing in musicians suggest that domain specific experience may enhance neural resources recruited for language specific behaviors. In everyday situations, listeners are faced with extracting speech signals in degraded listening conditions. Here, we examine whether musical training provides resilience to the degradative effects of reverberation on subcortical representations of pitch and formant-related harmonic information of speech. Brainstem frequency-following responses (FFRs) were recorded from musicians and non-musician controls in response to the vowel /i/ in four different levels of reverberation and analyzed based on their spectro-temporal composition. For both groups, reverberation had little effect on the neural encoding of pitch but significantly degraded neural encoding of formant-related harmonics (i.e., vowel quality) suggesting a differential impact on the source-filter components of speech. However, in quiet and across nearly all reverberation conditions, musicians showed more robust responses than non-musicians. Neurophysiologic results were confirmed behaviorally by comparing brainstem spectral magnitudes with perceptual measures of fundamental (F0) and first formant (F1) frequency difference limens (DLs). For both types of discrimination, musicians obtained DLs which were 2-4 times better than non-musicians. Results suggest that musicians' enhanced neural encoding of acoustic features, an experience-dependent effect, is more resistant to reverberation degradation which may explain their enhanced perceptual ability on behaviorally relevant speech and/or music tasks in adverse listening conditions. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Brainstem evoked response auditory in healthy term neonates with hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Isman Jafar

    2010-06-01

    bilirubin> 12 mg/dL will be subject for phototherapy. Objectives To determine the association between total bilirubin > 12 mg/dL and BERA abnonnalities in healthy tenn neonates, and the value of total bilirubin and free bilirubin that initiate abnonnal BERA. Methods This cross sectional study was carried out between March 31August 8, 2008, in healthy term neonates at roomingin ward, Department of Obstetric & Gy necology, Cipto Mangunkusumo Hospital (CMH. All eligible subjects were examined for Bf and BERA using standard methods.  Results The prevalence of abnormal BERA was 15.4%. There was no significant relation between hy perbilirubinemia (> 12 mg/ dL and abnonnal BERA in healthy tenn neonates. Lowest total bilirubin and Bf level related to abnonnal BERA were 12.4 mg/dL (mean 12.8 mg/dL and O.oSLg/dL (mean l.3Lg/dL, respectively. All BERA abnonnalities were unilateral. Conclusions There is no association between abnormal BERA and hyperbilirubinemia (total bilirubin> 12 mg/dL in jaundiced infants who undergo phototherapy.

  16. Auditory Brainstem Responses in Young Males with Fragile X Syndrome

    Science.gov (United States)

    Roberts, Joanne; Hennon, Elizabeth A.; Anderson, Kathleen; Roush, Jackson; Gravel, Judith; Skinner, Martie; Misenheimer, Jan; Reitz, Patricia

    2005-01-01

    Fragile X syndrome (FXS) is the most common inherited cause of mental retardation resulting in developmental delays in males. Atypical outer ear morphology is characteristic of FXS and may serve as a marker for abnormal auditory function. Despite this abnormality, studies of the hearing of young males with FXS are generally lacking. A few studies…

  17. Task-Related Suppression of the Brainstem Frequency following Response

    Science.gov (United States)

    2013-02-18

    fundamental stimuli. Int J Psychophysiol 19: 203–214. 50. Giard M-H, Collet L, Bouchet P, Pernier J (1994) Auditory selective attention in the human cochlea...Brain Research 633: 353–356. doi:10.1016/0006– 8993(94)91561-X. 51. Maison S, Micheyl C, Collet L (2001) Influence of focused auditory attention on

  18. Microsurgical removal of brainstem cavernoma: A report of 42 cases

    Directory of Open Access Journals (Sweden)

    Jian-ning ZHANG

    2012-08-01

    Full Text Available Objective To summarize the clinical features and the surgical approach and techniques for microsurgical removal of brainstem cavernoma, and to evaluate the efficacy of surgical treatment of brainstem cavernoma. Methods The clinical data of 41 brainstem cavernoma patients treated by microsurgical resection from January 2003 to April 2011 were retrospectively analyzed, and they were 23 males and 18 females, aged 8 to 62 years. The clinical presentations included signs and symptoms of increased intracranial pressure, such as headache and dizziness, long-tract signs such as cranial nerve dysfunction, numbness and decrease in muscle strength, and ataxia. According to the site of the lesions, surgical approaches were selected following the principle of "the shortest distance between the incision and the lesion". Intraoperative short-latency somatosensory evoked potential (SSEP and auditory evoked potential (AEP were monitored. Results Total resection of cavernoma was achieved in 35 patients, small residual tumor was left in 6 with giant lesions. No death occurred. Twenty-seven patients showed improvement in nerve function. Aggravation of pre-existing neurological disorders or appearance of new neurological disorders was found in 14 patients, including 2 with respiratory dysfunction who regained spontaneous breathing after assisted respiration for one week. Follow-up was carried out for 38 months in average. Neurological deficits have been restored in most patients, and no recurrence was found except for 1 case of re-bleeding from residual tumor. Conclusions According to the lesion site and protruding direction, individualized surgical approach can be selected following the "shortest distance" principle for the resection of brainstem cavernoma. The application of intraoperative navigation and electrophysiological monitoring of the brainstem is helpful in reducing surgical injury and decreasing the complications.

  19. The Structural, Functional and Molecular Organization of the Brainstem

    Directory of Open Access Journals (Sweden)

    Rudolf eNieuwenhuys

    2011-06-01

    Full Text Available According to Wilhelm His (1891, 1893 the brainstem consists of two longitudinal zones, the dorsal alar plate (sensory in nature and the ventral basal plate (motor in nature. Johnston and Herrick indicated that both plates can be subdivided into separate somatic and visceral zones, distinguishing somatosensory and viscerosensory zones within the alar plate, and visceromotor and somatomotor zones within the basal plate. To test the validity of this ‘four-functional-zones’ concept, I developed a topological procedure, surveying the spatial relationships of the various cell masses in the brainstem in a single figure. Brainstems of 16 different anamniote species were analyzed, and revealed that the brainstems are clearly divisible into four morphological zones, which correspond largely with the functional zones of Johnston and Herrick. Exceptions include (1 the magnocellular vestibular nucleus situated in the viscerosensory zone; (2 the basal plate containing a number of evidently non-motor centres (superior and inferior olives. Nevertheless the ‘functional zonal model’ has explanatory value. Thus, it is possible to interpret certain brain specializations related to particular behavioural profiles, as ‘local hypertrophies’ of one or two functional columns. Recent developmental molecular studies on brains of birds and mammals confirmed the presence of longitudinal zones, and also showed molecularly defined transverse bands or neuromeres throughout development. The intersecting boundaries of the longitudinal zones and the transverse bands appeared to delimit radially arranged histogenetic domains. Because neuromeres have been observed in embryonic and larval stages of numerous anamniote species, it may be hypothesized that the brainstems of all vertebrates share a basic organizational plan, in which intersecting longitudinal and transverse zones form fundamental histogenetic and genoarchitectonic units.

  20. Detection of Perinatal Cytomegalovirus Infection and Sensorineural Hearing Loss in Belgian Infants by Measurement of Automated Auditory Brainstem Response▿

    OpenAIRE

    Verbeeck, Jannick; Van Kerschaver, Erwin; Wollants, Elke; Beuselinck, Kurt; Stappaerts, Luc; Van Ranst, Marc

    2008-01-01

    Since auditory disability causes serious problems in the development of speech and in the total development of a child, it is crucial to diagnose possible hearing impairment as soon as possible after birth. This study evaluates the neonatal hearing screening program in Flanders, Belgium. The auditory ability of 118,438 babies was tested using the automated auditory brainstem response. We selected 194 babies with indicative hearing impairment and 332 matched controls to investigate the associa...

  1. The value of 201thallium-SPECT imaging in childhood brainstem gliomas.

    Science.gov (United States)

    Nadvi, S S; Ebrahim, F S; Corr, P

    1998-08-01

    To compare 201thallium (T1) uptake and SPECT with MRI in children with brainstem gliomas. Ten children with brainstem gliomas were prospectively evaluated by 201Tl-SPECT and MRI. Histological verification was obtained in eight children - two died prior to surgery. Quantitative thallium uptake index (UI) was obtainable in five cases and was compared to tumour grade. In addition, two patients with known benign brainstem lesions (neurofibromatosis and tuberculoma) were similarly prospectively evaluated. All children with brainstem glioma accumulated thallium. (Mean U1 3.23, 100% sensitivity). The single patient with brainstem tuberculoma also accumulated thallium (UI 2.80, 91.7% specificity). There was no correlation between thallium uptake and tumour grade. Uptake could not be conclusively correlated with the following MR features: gadolinium enhancement, exophytic or intrinsic gliomas, necrosis and location of glioma within the brainstem. 201T1-SPECT is a promising imaging adjunct in the assessment of childhood brainstem gliomas.

  2. Diffusion tensor imaging of the brainstem in children with achondroplasia.

    Science.gov (United States)

    Bosemani, Thangamadhan; Orman, Gunes; Carson, Kathryn A; Meoded, Avner; Huisman, Thierry A G M; Poretti, Andrea

    2014-11-01

    The aims of this study were to compare, using diffusion tensor imaging (DTI) of the brainstem, microstructural integrity of the white matter in children with achondroplasia and age-matched participants and to correlate the severity of craniocervical junction (CCJ) narrowing and neurological findings with DTI scalars in children with achondroplasia. This study also aimed to assess the potential role of fibroblast growth factor receptor type 3 on white matter microstructure. Diffusion tensor imaging was performed using a 1.5T magnetic resonance scanner and balanced pairs of diffusion gradients along 20 non-collinear directions. Measurements were obtained from regions of interest, sampled in each pontine corticospinal tract (CST), medial lemniscus, and middle cerebellar peduncle, as well as in the lower brainstem and centrum semiovale, for fractional anisotropy and for mean, axial, and radial diffusivity. In addition, a severity score for achondroplasia was assessed by measuring CCJ narrowing. Eight patients with achondroplasia (seven males, one female; mean age 5y 6mo, range 1y 1mo-15y 1mo) and eight age- and sex-matched comparison participants (mean age 5y 2mo, range 1y 1mo-14y 11mo) were included in this study. Fractional anisotropy was lower and mean diffusivity and radial diffusivity were higher in the lower brainstem of patients with achondroplasia than in age-matched comparison participants. The CST and middle cerebellar peduncle of the participants showed increases in mean, axial, and radial diffusivity. Fractional anisotropy in the lower brainstem was negatively correlated with the degree of CCJ narrowing. No differences in the DTI metrics of the centrum semiovale were observed between the two groups. The reduction in fractional anisotropy and increase in diffusivities in the lower brainstem of participants with achondroplasia may reflect secondary encephalomalacic degeneration and cavitation of the affected white matter tracts as shown by histology. In

  3. Enhanced Excitatory Connectivity and Disturbed Sound Processing in the Auditory Brainstem of Fragile X Mice.

    Science.gov (United States)

    Garcia-Pino, Elisabet; Gessele, Nikodemus; Koch, Ursula

    2017-08-02

    Hypersensitivity to sounds is one of the prevalent symptoms in individuals with Fragile X syndrome (FXS). It manifests behaviorally early during development and is often used as a landmark for treatment efficacy. However, the physiological mechanisms and circuit-level alterations underlying this aberrant behavior remain poorly understood. Using the mouse model of FXS ( Fmr1 KO ), we demonstrate that functional maturation of auditory brainstem synapses is impaired in FXS. Fmr1 KO mice showed a greatly enhanced excitatory synaptic input strength in neurons of the lateral superior olive (LSO), a prominent auditory brainstem nucleus, which integrates ipsilateral excitation and contralateral inhibition to compute interaural level differences. Conversely, the glycinergic, inhibitory input properties remained unaffected. The enhanced excitation was the result of an increased number of cochlear nucleus fibers converging onto one LSO neuron, without changing individual synapse properties. Concomitantly, immunolabeling of excitatory ending markers revealed an increase in the immunolabeled area, supporting abnormally elevated excitatory input numbers. Intrinsic firing properties were only slightly enhanced. In line with the disturbed development of LSO circuitry, auditory processing was also affected in adult Fmr1 KO mice as shown with single-unit recordings of LSO neurons. These processing deficits manifested as an increase in firing rate, a broadening of the frequency response area, and a shift in the interaural level difference function of LSO neurons. Our results suggest that this aberrant synaptic development of auditory brainstem circuits might be a major underlying cause of the auditory processing deficits in FXS. SIGNIFICANCE STATEMENT Fragile X Syndrome (FXS) is the most common inheritable form of intellectual impairment, including autism. A core symptom of FXS is extreme sensitivity to loud sounds. This is one reason why individuals with FXS tend to avoid social

  4. Mosaic Evolution of Brainstem Motor Nuclei in Catarrhine Primates

    Directory of Open Access Journals (Sweden)

    Seth D. Dobson

    2011-01-01

    Full Text Available Facial motor nucleus volume coevolves with both social group size and primary visual cortex volume in catarrhine primates as part of a specialized neuroethological system for communication using facial expressions. Here, we examine whether facial nucleus volume also coevolves with functionally unrelated brainstem motor nuclei (trigeminal motor and hypoglossal due to developmental constraints. Using phylogenetically informed multiple regression analyses of previously published brain component data, we demonstrate that facial nucleus volume is not correlated with the volume of other motor nuclei after controlling for medulla volume. Our results show that brainstem motor nuclei can evolve independently of other developmentally linked structures in association with specific behavioral ecological conditions. This finding provides additional support for the mosaic view of brain evolution.

  5. Process evaluation of the health education resource Abre los Ojos for street-involved youth in Medellín

    Directory of Open Access Journals (Sweden)

    John L. Wylie

    2012-02-01

    Full Text Available Objective: Conduct a process evaluation of a health education resource (pamphlet¸ Abre los Ojos, designed for street-involved youth in Medellín. The primary foci of the evaluation were the process of developing the resource and youth’s subsequent perception of the resource. Methodology: Drawing upon both qualitative and quantitative data, a process evaluation was undertaken. Ninety four street-involved youth between the ages of 14–24 years completed surveys about the resource. These semi-structured interviews were key for the information about youth perception of the resource. In addition to individual interviews, prior to resource creation, a series of focus groups were integral for the development of the resource. Results: The process of consulting with the target population through the focus groups was effective in obtaining their ideas and feedback about what type of content they would like to see in a health education resource, and how they wanted that content presented. After distribution, participants described that Abre los Ojos contained information that was valuable and relevant to their experiences. While not a primary focus of this evaluation, the individual interviews were also able to provide some preliminary insight into whether Abre los Ojos was an effective means for participants to increase their knowledge of content included in the resource. Conclusion: The collaborative process of jointly developing the resource content in partnership with the youth proved very worthwhile. While our research team chose to include information about HIV, through focus group dialogue, the youth themselves determined the additional content themes (piercings, use of solvents, and description of life on the street. The resulting resource was well-received by members of the street-involved population who had not been involved in its design.

  6. Spontaneous remission of a diffuse brainstem lesion in a neonate

    Energy Technology Data Exchange (ETDEWEB)

    Schomerus, Leena; Kahn, Thomas [University of Leipzig, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Merkenschlager, Andreas [University of Leipzig, Department of Pediatric Neurology, Leipzig (Germany); Hirsch, Wolfgang [University of Leipzig, Pediatric Radiology, Department of Diagnostic and Interventional Radiology, Leipzig (Germany)

    2007-04-15

    We describe here the spontaneous remission of a diffuse brainstem lesion found in an infant at the age of 7 weeks. Clinical and MRI characteristics strongly suggested a diffuse pontine glioma. Repeated MRI studies showed a continuous decrease in the size of the lesion, which was no longer visible by the age of 27 months. Spontaneous remission of diffuse pontine glioma is extremely rare; to our knowledge there are reports of only three similar cases. (orig.)

  7. Thalamic, brainstem, and cerebellar glucose metabolism in the hemiplegic monkey

    Energy Technology Data Exchange (ETDEWEB)

    Shimoyama, I.; Dauth, G.W.; Gilman, S.; Frey, K.A.; Penney, J.B. Jr.

    1988-12-01

    Unilateral ablation of cerebral cortical areas 4 and 6 of Brodmann in the macaque monkey results in a contralateral hemiplegia that resolves partially with time. During the phase of dense hemiplegia, local cerebral metabolic rate for glucose (1CMRG1c) is decreased significantly in most of the thalamic nuclei ipsilateral to the ablation, and there are slight contralateral decreases. The lCMRGlc is reduced bilaterally in most of the brainstem nuclei and bilaterally in the deep cerebellar nuclei, but only in the contralateral cerebellar cortex. During the phase of partial motor recovery, lCMRGlc is incompletely restored in many of the thalamic nuclei ipsilateral to the ablation and completely restored in the contralateral nuclei. In the brainstem and deep cerebellar nuclei, poor to moderate recovery occurs bilaterally. Moderate recovery occurs in the contralateral cerebellar cortex. The findings demonstrate that a unilateral cerebral cortical lesion strongly affects lCMRGlc in the thalamus ipsilaterally and in the cerebellar cortex contralaterally, but in the brainstem bilaterally. Partial recovery of lCMRGlc accompanies the progressive motor recovery. The structures affected include those with direct, and also those with indirect, connections to the areas ablated.

  8. Mapping of neurokinin-like immunoreactivity in the human brainstem

    Directory of Open Access Journals (Sweden)

    Narvaez Jose

    2003-02-01

    Full Text Available Abstract Background Using an indirect immunoperoxidase technique, we have studied the distribution of immunoreactive fibers and cell bodies containing neurokinin in the adult human brainstem with no prior history of neurological or psychiatric disease. Results Clusters of immunoreactive cell bodies and high densities of neurokinin-immunoreactive fibers were located in the periaqueductal gray, the dorsal motor nucleus of the vagus and in the reticular formation of the medulla, pons and mesencephalon. Moreover, immunoreactive cell bodies were found in the inferior colliculus, the raphe obscurus, the nucleus prepositus hypoglossi, and in the midline of the anterior medulla oblongata. In general, immunoreactive fibers containing neurokinin were observed throughout the whole brainstem. In addition to the nuclei mentioned above, the highest densities of such immunoreactive fibers were located in the spinal trigeminal nucleus, the lateral reticular nucleus, the nucleus of the solitary tract, the superior colliculus, the substantia nigra, the nucleus ambiguus, the gracile nucleus, the cuneate nucleus, the motor hypoglossal nucleus, the medial and superior vestibular nuclei, the nucleus prepositus hypoglossi and the interpeduncular nucleus. Conclusion The widespread distribution of immunoreactive structures containing neurokinin in the human brainstem indicates that neurokinin might be involved in several physiological mechanisms, acting as a neurotransmitter and/or neuromodulator.

  9. [Fisher syndrome and Bickerstaff brainstem encephalitis].

    Science.gov (United States)

    Kuwabara, Satoshi

    2014-01-01

    This review described current status and perspectives of treatment for immune-mediated neuropathies, such as Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy (CIDP), multifocal motor neuropathy, and demyelinating neuropathy with anti-MAG neuropathy. corticosteroids, immunoglobulin therapy, and plasmapheresis are conventional treatments for these neuropathies, but the responsiveness to the treatments significantly differ among the disorders. Promising new treatment options include anti-complement monoclonal antibody (Eculizumab, anti-C5) for Guillain-Barre syndrome, and rituximab (anti-CD20) for anti-MAG neuropathy. For CIDP, different treatments would be required according to the clinical subtypes; typical CIDP and asymmetric variabt). For multifocal neuropathy, maintainance treatment with immunoglobulin is necessary.

  10. A combination anaerobic digestion scheme for biogas production from dairy effluent-CSTR and ABR, and biogas upgrading

    DEFF Research Database (Denmark)

    Jürgensen, Lars; Ehimen, Ehiaze Augustine; Born, Jens

    2018-01-01

    Anaerobic digestion of low-strength dairy waste water was used for the production of biogas which is aimed at serving as a concentrated carbon dioxide (CO2) source for further methanation. Using hydrogen (which can be produced via electrolysis using renewably sourced electricity), the CO2 fraction...... of the produced biogas can be used as a mechanism to store surplus electricity by the Sabatier process, which converts the CO2 fractions to methane (CH4), i. e. synthetic natural gas. This study investigates the use a combined reactor scheme for the anaerobic digestion of dairy waste water, and the further...... upgrading of the biogas products from the process. A combination pilot scale process was established with a 90 d start-up time using a 1 m3 continuous stirred tank reactor (CSTR) and a 0.2 m3 baffled reactor (ABR) in series. The system was fed at constant retention time in the ABR of 1.6 d and with varying...

  11. Effect of hydraulic retention time on ABR tail water treatment by contact oxidation process under low oxygen condition

    Science.gov (United States)

    Huang, Xiaolong; Shi, Chunhong; Wang, Zhenbao; Jiang, Kai

    2018-02-01

    Biological contact oxidation process of low dissolved oxygen was applied to the treatment of ABR tail water, which were pretreatment effluent for Island sewage. The reactor was built and filled with polyurethane suspension filler as carrier for biofilm growth in laboratory. The dissolved oxygen in the reactor is kept at 1.3-1.8mg/L to distinguish between traditional method which is 2.5-3.5mg/L. Influence of hydraulic retention time(HRT) on ABR tail water treatment by the process was studied. Results show that the system has good effect on removal of COD and TN under this condition. When HRT is among 4h to 12h, the removal rate of COD can be maintained at 80-90%.From period 1 to period 3, the removal rate of NH4 +N and TN at the end of each period can be recovered to a higher level, and the average removal rate after stabilization is 99% and 67% respectively which can come up to first grade of the national standard GB18918-2002. It is remarkable that when HRT is 4h, the removal rate of NH4 +-N and TN showed a significant decrease trend, the concentration of effluent was 14.79mg/L and 19.5mg/L, respectively.

  12. The behaviour of an anaerobic baffled reactor (ABR as the first stage in the biological treatment of hog farming effluents

    Directory of Open Access Journals (Sweden)

    F. Motteran

    2013-06-01

    Full Text Available This present paper reports a study of the efficiency of an anaerobic Baffled Reactor (ABR composed of three chambers working as the first stage of a biological treatment system for swine wastewater, over a period of 116 days. The average value of the volumetric organic loading rate (VOLR was 17.8 kgCODtotal m-3 d-1, the biological organic loading rates (BOLR based on total and filtered COD influents of 14381 mg L-1 and 3610 mg L-1, respectively, were: 1.3 kgCODtotal kgTVS d-1 and 0.98 kgCODfiltered kgTVS d-1, respectively, and the hydraulic loading rate (HLR was about 1.4 m³ m-3 d-1. The average removal efficiency for total COD was 80% at a hydraulic retention time (HRT of about 18 hours. The average alkalinity in the effluent was 3801 mgCaCO3 L-1. The average removal efficiencies for oil and grease and total soluble solids were 41% and 78%, respectively. The sludge granulation and biogas production in the ABR were quite different between the first and third compartment, showing a distinct microbial consortium in each chamber. Through this research it was confirmed that this type of reactor can be employed as the first stage in a system treating swine wastewater.

  13. The effect of prostaglandin E1 on brainstem blood flow disturbance in an animal model of vertebrobasilar insufficiency.

    Science.gov (United States)

    Yamanaka, Toshiaki; Murai, Takayuki; Sawai, Yachiyo; Okamoto, Hideyuki; Hosoi, Hiroshi

    2014-05-01

    Using an animal model of vertebrobasilar insufficiency (VBI), in which brainstem circulatory disturbance was induced in rats, we examined how prostaglandin E1 (PG-E1) affects brainstem blood flow (BBF) to clarify whether it is effective against VBI. Fifteen healthy male Wister rats that displayed positive responses to Preyer's reflex were used. Their BBF was continuously measured on the left side of the midline of the brainstem using laser Doppler flowmetry. A rat model of VBI, a pathological condition that presents with decreased BBF, was prepared by applying a vertebral artery clamp ipsilateral to the BBF measuring site and inducing hypotension of 60-70 mmHg by blood withdrawal. Saline as a control (n = 5), 5 ng/kg/min (n = 5) or 10 ng/kg/min (n = 5) PG-E1 at a dose was continuously administered to the rats using a motor-driven syringe pump. The effects of the drugs on the rats' BBF were evaluated. BBF, which was decreased by the unilateral vertebral artery clamping combined with blood withdrawal-induced hypotension, recovered in a dose-dependent manner after the administration of 5 or 10 ng/kg/min PG-E1, and complete recovery to the baseline level was achieved by 60 min treatment; however, no such effect was observed for intravenous saline. These results suggest that PG-E1 acts on local vessels and improves blood flow insufficiency in the brainstem in our animal model of VBI. PG-E1 might be useful as a cerebral vasodilator for VBI.

  14. Intrinsic brainstem schwannoma – A rare clinical entity and a histological enigma

    Directory of Open Access Journals (Sweden)

    Anil Kumar Sharma

    2016-01-01

    Full Text Available Intraparenchymal schwannomas arising in the brainstem are very rare, and only eight cases have been reported in literature till now. We report an intraparenchymal brainstem schwannoma presenting with the classical clinical presentation of an intrinsic brainstem lesion, and discuss its clinicoradiological characteristics and histological origins. We highlight the importance of an intraoperative frozen section diagnosis in such cases. Intraoperative tissue diagnosis significantly may alter the surgical strategy, which should be aimed at near total intracapsular decompression of the schwannoma.

  15. Non-homeostatic body weight regulation through a brainstem-restricted receptor for GDF15.

    Science.gov (United States)

    Hsu, Jer-Yuan; Crawley, Suzanne; Chen, Michael; Ayupova, Dina A; Lindhout, Darrin A; Higbee, Jared; Kutach, Alan; Joo, William; Gao, Zhengyu; Fu, Diana; To, Carmen; Mondal, Kalyani; Li, Betty; Kekatpure, Avantika; Wang, Marilyn; Laird, Teresa; Horner, Geoffrey; Chan, Jackie; McEntee, Michele; Lopez, Manuel; Lakshminarasimhan, Damodharan; White, Andre; Wang, Sheng-Ping; Yao, Jun; Yie, Junming; Matern, Hugo; Solloway, Mark; Haldankar, Raj; Parsons, Thomas; Tang, Jie; Shen, Wenyan D; Alice Chen, Yu; Tian, Hui; Allan, Bernard B

    2017-10-12

    Under homeostatic conditions, animals use well-defined hypothalamic neural circuits to help maintain stable body weight, by integrating metabolic and hormonal signals from the periphery to balance food consumption and energy expenditure. In stressed or disease conditions, however, animals use alternative neuronal pathways to adapt to the metabolic challenges of altered energy demand. Recent studies have identified brain areas outside the hypothalamus that are activated under these 'non-homeostatic' conditions, but the molecular nature of the peripheral signals and brain-localized receptors that activate these circuits remains elusive. Here we identify glial cell-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) as a brainstem-restricted receptor for growth and differentiation factor 15 (GDF15). GDF15 regulates food intake, energy expenditure and body weight in response to metabolic and toxin-induced stresses; we show that Gfral knockout mice are hyperphagic under stressed conditions and are resistant to chemotherapy-induced anorexia and body weight loss. GDF15 activates GFRAL-expressing neurons localized exclusively in the area postrema and nucleus tractus solitarius of the mouse brainstem. It then triggers the activation of neurons localized within the parabrachial nucleus and central amygdala, which constitute part of the 'emergency circuit' that shapes feeding responses to stressful conditions. GDF15 levels increase in response to tissue stress and injury, and elevated levels are associated with body weight loss in numerous chronic human diseases. By isolating GFRAL as the receptor for GDF15-induced anorexia and weight loss, we identify a mechanistic basis for the non-homeostatic regulation of neural circuitry by a peripheral signal associated with tissue damage and stress. These findings provide opportunities to develop therapeutic agents for the treatment of disorders with altered energy demand.

  16. Non-homeostatic body weight regulation through a brainstem-restricted receptor for GDF15

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Jer-Yuan; Crawley, Suzanne; Chen, Michael; Ayupova, Dina A.; Lindhout, Darrin A.; Higbee, Jared; Kutach, Alan; Joo, William; Gao, Zhengyu; Fu, Diana; To, Carmen; Mondal, Kalyani; Li, Betty; Kekatpure, Avantika; Wang, Marilyn; Laird, Teresa; Horner, Geoffrey; Chan, Jackie; McEntee, Michele; Lopez, Manuel; Lakshminarasimhan, Damodharan; White, Andre; Wang, Sheng-Ping; Yao, Jun; Yie, Junming; Matern, Hugo; Solloway, Mark; Haldankar, Raj; Parsons, Thomas; Tang, Jie; Shen, Wenyan D.; Alice Chen, Yu; Tian, Hui; Allan, Bernard B.

    2017-09-27

    Under homeostatic conditions, animals use well-defined hypothalamic neural circuits to help maintain stable body weight, by integrating metabolic and hormonal signals from the periphery to balance food consumption and energy expenditure1,2. In stressed or disease conditions, however, animals use alternative neuronal pathways to adapt to the metabolic challenges of altered energy demand3. Recent studies have identified brain areas outside the hypothalamus that are activated under these ‘non-homeostatic’ conditions4,5,6, but the molecular nature of the peripheral signals and brain-localized receptors that activate these circuits remains elusive. Here we identify glial cell-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) as a brainstem-restricted receptor for growth and differentiation factor 15 (GDF15). GDF15 regulates food intake, energy expenditure and body weight in response to metabolic and toxin-induced stresses; we show that Gfral knockout mice are hyperphagic under stressed conditions and are resistant to chemotherapy-induced anorexia and body weight loss. GDF15 activates GFRAL-expressing neurons localized exclusively in the area postrema and nucleus tractus solitarius of the mouse brainstem. It then triggers the activation of neurons localized within the parabrachial nucleus and central amygdala, which constitute part of the ‘emergency circuit’ that shapes feeding responses to stressful conditions7. GDF15 levels increase in response to tissue stress and injury, and elevated levels are associated with body weight loss in numerous chronic human diseases8,9. By isolating GFRAL as the receptor for GDF15-induced anorexia and weight loss, we identify a mechanistic basis for the non-homeostatic regulation of neural circuitry by a peripheral signal associated with tissue damage and stress. These findings provide opportunities to develop therapeutic agents for the treatment of disorders with altered energy demand.

  17. The development of descending projections from the brainstem to the spinal cord in the fetal sheep

    Directory of Open Access Journals (Sweden)

    Cooke Ian RC

    2007-06-01

    Full Text Available Abstract Background Although the fetal sheep is a favoured model for studying the ontogeny of physiological control systems, there are no descriptions of the timing of arrival of the projections of supraspinal origin that regulate somatic and visceral function. In the early development of birds and mammals, spontaneous motor activity is generated within spinal circuits, but as development proceeds, a distinct change occurs in spontaneous motor patterns that is dependent on the presence of intact, descending inputs to the spinal cord. In the fetal sheep, this change occurs at approximately 65 days gestation (G65, so we therefore hypothesised that spinally-projecting axons from the neurons responsible for transforming fetal behaviour must arrive at the spinal cord level shortly before G65. Accordingly we aimed to identify the brainstem neurons that send projections to the spinal cord in the mature sheep fetus at G140 (term = G147 with retrograde tracing, and thus to establish whether any projections from the brainstem were absent from the spinal cord at G55, an age prior to the marked change in fetal motor activity has occurred. Results At G140, CTB labelled cells were found within and around nuclei in the reticular formation of the medulla and pons, within the vestibular nucleus, raphe complex, red nucleus, and the nucleus of the solitary tract. This pattern of labelling is similar to that previously reported in other species. The distribution of CTB labelled neurons in the G55 fetus was similar to that of the G140 fetus. Conclusion The brainstem nuclei that contain neurons which project axons to the spinal cord in the fetal sheep are the same as in other mammalian species. All projections present in the mature fetus at G140 have already arrived at the spinal cord by approximately one third of the way through gestation. The demonstration that the neurons responsible for transforming fetal behaviour in early ontogeny have already reached the

  18. Descending Command Neurons in the Brainstem that Halt Locomotion

    DEFF Research Database (Denmark)

    Bouvier, Julien; Caggiano, Vittorio; Leiras, Roberto

    2015-01-01

    identifiable brainstem populations to a potential locomotor stop signal, we used developmental genetics and considered a discrete neuronal population in the reticular formation: the V2a neurons. We find that those neurons constitute a major excitatory pathway to locomotor areas of the ventral spinal cord....... Selective activation of V2a neurons of the rostral medulla stops ongoing locomotor activity, owing to an inhibition of premotor locomotor networks in the spinal cord. Moreover, inactivation of such neurons decreases spontaneous stopping in vivo. Therefore, the V2a "stop neurons" represent a glutamatergic...

  19. [Differential diagnostics of peripheral vestibular and brainstem-cerebellar syndrome].

    Science.gov (United States)

    Likhachev, S A; Tarasevich, N M

    2013-01-01

    The objective of the present study was to develop criteria for differential diagnostics of peripheral vestibular and brainstem-cerebellar syndrome based on the analysis of characteristics of evoked vestibular myogenic potentials. A total of 59 patients presenting with unilateral peripheral vestibular syndrome (PVS), 60 patients with demyelinizing disease of CNS, and 20 healthy subjects were available for the examination by the method of evoked vestibular myogenic potentials. The values of representativity and latency parameters PI, N1, PINI and amplitude parameters PI, NI, PINI were obtained. It was shown that latency PI in the patients with demyelinizing disease of CNS is higher than in those with PVS.

  20. Using Aesthetic Response, a Poetic Inquiry to Expand Knowing

    DEFF Research Database (Denmark)

    Gerge, Anna; Warja, Margareta; Pedersen, Inge Nygaard

    2017-01-01

    Using Aesthetic Response, a Poetic Inquiry to Expand Knowing Abstract: The Rx6-Method A simple step-wise research procedure of arts-based research (ABR) called the Rx6 method is presented. This ABR method is grounded in expressive arts therapy, heuristic inquiry, attachment theory and contemporary...... understanding of the studied phenomena. The complexity of sharing implicit processes and tacit knowledge, its caveats and gains, along with theoretical perspectives of such undertakings, are presented and discussed....

  1. Modular organization of the brainstem noradrenaline system coordinates opposing learning states.

    Science.gov (United States)

    Uematsu, Akira; Tan, Bao Zhen; Ycu, Edgar A; Cuevas, Jessica Sulkes; Koivumaa, Jenny; Junyent, Felix; Kremer, Eric J; Witten, Ilana B; Deisseroth, Karl; Johansen, Joshua P

    2017-11-01

    Noradrenaline modulates global brain states and diverse behaviors through what is traditionally believed to be a homogeneous cell population in the brainstem locus coeruleus (LC). However, it is unclear how LC coordinates disparate behavioral functions. We report a modular LC organization in rats, endowed with distinct neural projection patterns and coding properties for flexible specification of opposing behavioral learning states. LC projection mapping revealed functionally distinct cell modules with specific anatomical connectivity. An amygdala-projecting ensemble promoted aversive learning, while an independent medial prefrontal cortex-projecting ensemble extinguished aversive responses to enable flexible behavior. LC neurons displayed context-dependent inter-relationships, with moderate, discrete activation of distinct cell populations by fear or safety cues and robust, global recruitment of most cells by strong aversive stimuli. These results demonstrate a modular organization in LC in which combinatorial activation modes are coordinated with projection- and behavior-specific cell populations, enabling adaptive tuning of emotional responding and behavioral flexibility.

  2. Multiple serotonergic brainstem abnormalities in sudden infant death syndrome.

    Science.gov (United States)

    Paterson, David S; Trachtenberg, Felicia L; Thompson, Eric G; Belliveau, Richard A; Beggs, Alan H; Darnall, Ryan; Chadwick, Amy E; Krous, Henry F; Kinney, Hannah C

    2006-11-01

    The serotonergic (5-hydroxytryptamine [5-HT]) neurons in the medulla oblongata project extensively to autonomic and respiratory nuclei in the brainstem and spinal cord and help regulate homeostatic function. Previously, abnormalities in 5-HT receptor binding in the medullae of infants dying from sudden infant death syndrome (SIDS) were identified, suggesting that medullary 5-HT dysfunction may be responsible for a subset of SIDS cases. To investigate cellular defects associated with altered 5-HT receptor binding in the 5-HT pathways of the medulla in SIDS cases. Frozen medullae from infants dying from SIDS (cases) or from causes other than SIDS (controls) were obtained from the San Diego Medical Examiner's office between 1997 and 2005. Markers of 5-HT function were compared between SIDS cases and controls, adjusted for postconceptional age and postmortem interval. The number of samples available for each analysis ranged from 16 to 31 for SIDS cases and 6 to 10 for controls. An exploratory analysis of the correlation between markers and 6 recognized risk factors for SIDS was performed. 5-HT neuron count and density, 5-HT(1A) receptor binding density, and 5-HT transporter (5-HTT) binding density in the medullary 5-HT system; correlation between these markers and 6 recognized risk factors for SIDS. Compared with controls, SIDS cases had a significantly higher 5-HT neuron count (mean [SD], 148.04 [51.96] vs 72.56 [52.36] cells, respectively; P<.001) and 5-HT neuron density (P<.001), as well as a significantly lower density of 5-HT(1A) receptor binding sites (P

  3. Age-related changes in the guinea pig auditory cortex: relationship with brainstem changes and comparison with tone-induced hearing loss.

    Science.gov (United States)

    Gourévitch, Boris; Edeline, Jean-Marc

    2011-12-01

    Elderly people often show degraded hearing performance and have difficulties in understanding speech, particularly in noisy environments. Although loss in peripheral hearing sensitivity is an important factor in explaining these low performances, central alterations also have an impact but their exact contributions remained unclear. In this study, we focus on the functional effects of aging on auditory cortex responses. Neuronal discharges and local field potentials were recorded in the auditory cortex of aged guinea pigs (> 3 years), and several parameters characterizing the processing of auditory information were quantified: the acoustic thresholds, response strength, latency and duration of the response, and breadth of tuning. Several of these parameters were also quantified from auditory brainstem responses collected from the same animals, and recordings obtained from a population of animals with trauma-induced hearing loss were also included in this study. The results showed that aging and acoustic trauma reduced the response strength at both brainstem and cortical levels, and increased the response latencies more at the cortical level than at the brainstem level. In addition to the brainstem hearing loss, aging induced a 'cortical hearing loss' as judged by additive changes in the threshold and frequency response seen in the cortex. It also increased the duration of neural responses and reduced the receptive field bandwidth, effects that were not found in traumatized animals. These effects substantiate the notion that presbycusis involves both peripheral hearing loss and biological aging in the central auditory system. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  4. Dopamine and the Brainstem Locomotor Networks: From Lamprey to Human

    Directory of Open Access Journals (Sweden)

    Dimitri Ryczko

    2017-05-01

    Full Text Available In vertebrates, dopamine neurons are classically known to modulate locomotion via their ascending projections to the basal ganglia that project to brainstem locomotor networks. An increased dopaminergic tone is associated with increase in locomotor activity. In pathological conditions where dopamine cells are lost, such as in Parkinson's disease, locomotor deficits are traditionally associated with the reduced ascending dopaminergic input to the basal ganglia. However, a descending dopaminergic pathway originating from the substantia nigra pars compacta was recently discovered. It innervates the mesencephalic locomotor region (MLR from basal vertebrates to mammals. This pathway was shown to increase locomotor output in lampreys, and could very well play an important role in mammals. Here, we provide a detailed account on the newly found dopaminergic pathway in lamprey, salamander, rat, monkey, and human. In lampreys and salamanders, dopamine release in the MLR is associated with the activation of reticulospinal neurons that carry the locomotor command to the spinal cord. Dopamine release in the MLR potentiates locomotor movements through a D1-receptor mechanism in lampreys. In rats, stimulation of the substantia nigra pars compacta elicited dopamine release in the pedunculopontine nucleus, a known part of the MLR. In a monkey model of Parkinson's disease, a reduced dopaminergic innervation of the brainstem locomotor networks was reported. Dopaminergic fibers are also present in human pedunculopontine nucleus. We discuss the conserved locomotor role of this pathway from lamprey to mammals, and the hypothesis that this pathway could play a role in the locomotor deficits reported in Parkinson's disease.

  5. Brainstem encephalitis and acute polyneuropathy associated with hepatitis E infection.

    Science.gov (United States)

    Salim, Omar Jabbar; Davidson, Amy; Li, Kathy; Leach, John Paul; Heath, Craig

    2017-09-11

    A 59-year-old man presented with feverish illness. His Glasgow Coma Scale was 15, had reduced visual acuity in the left eye with partial left ptosis and mild left hemiparesis with an extensor left plantar. Over 48 hours, he accrued multiple cranial nerves palsies and progressed to a flaccid paralysis necessitating admission to an intensive care unit.Cerebrospinal fluid (CSF) study showed 20 lymphocytes and raised protein. Viral and bacterial PCRs were negative. Samples for Lyme, blood-borne viruses, syphilis and autoantibodies were also negative. MRI brain showed T2 abnormalities within the brainstem. Nerve conduction studies revealed an acute motor and sensory axonal neuropathy pattern of Guillian Barre Syndrome (GBS). The patient was treated for both infective and inflammatory causes of brainstem encephalitis and GBS.Retrospective studies confirmed the presence of hepatitis E virus (HEV) RNA in CSF and serum studies showed positive HEV IgG and IgM prior to intravenous infusion. After 3 months of intensive rehabilitation, the patient was discharged home walking with a frame. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Brainstem mechanisms underlying the cough reflex and its regulation.

    Science.gov (United States)

    Mutolo, Donatella

    2017-09-01

    Cough is a very important airway protective reflex. Cough-related inputs are conveyed to the caudal nucleus tractus solitarii (cNTS) that projects to the brainstem respiratory network. The latter is reconfigured to generate the cough motor pattern. A high degree of modulation is exerted on second-order neurons and the brainstem respiratory network by sensory inputs and higher brain areas. Two medullary structures proved to have key functions in cough production and to be strategic sites of action for centrally active drugs: the cNTS and the caudal ventral respiratory group (cVRG). Drugs microinjected into these medullary structures caused downregulation or upregulation of the cough reflex. The results suggest that inhibition and disinhibition are prominent regulatory mechanisms of this reflex and that both the cNTS and the cVRG are essential in the generation of the entire cough motor pattern. Studies on the basic neural mechanisms subserving the cough reflex may provide hints for novel therapeutic approaches. Different proposals for further investigations are advanced. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Recurrent Diplopia in a Pediatric Patient with Bickerstaff Brainstem Encephalitis

    Directory of Open Access Journals (Sweden)

    Scott A. McLeod

    2016-01-01

    Full Text Available Introduction. Acute complete external ophthalmoplegia is a rare finding in clinical practice that is associated with diseases affecting the neuromuscular junction, the oculomotor nerves, or the brainstem. Ophthalmoplegia has been reported with acute ataxia in Miller Fisher syndrome (MFS and Bickerstaff brainstem encephalitis (BBE. Up to 95% of these cases are associated with anti-GQ1b antibodies. Only a small number of cases of anti-GQ1b negative MFS have been documented in pediatric patients. This is the first case reporting a recurrence of ocular symptoms in an anti-GQ1b antibody negative patient with BBE. Case Presentation. An 8-year-old Caucasian boy presented with complete external ophthalmoplegia without ptosis, cerebellar ataxia, and a disturbance of consciousness. He had recently recovered from a confirmed Campylobacter jejuni infection. On subsequent laboratory testing he was anti-GQ1b antibody negative. He had a recurrence of diplopia at four-week follow-up. Conclusions. This patient’s recurrence of diplopia was treated with a five-week course of oral corticosteroids which did not worsen his condition, and this may be a therapeutic option for similar patients. We will discuss the symptoms and treatment of reported pediatric cases of anti-GQ1b antibody negative cases of MFS and the variation between cases representing a spectrum of illness.

  8. Mobius Syndrome Or Brainstem Dysgenesis : Case Description And Mini Review

    Directory of Open Access Journals (Sweden)

    Thankappan Bindu

    2005-01-01

    Full Text Available Background : Mobius syndrome is traditionally know as a non-progressive developmental disorder of cranial nerve nuclei mainly the sixth and the seventh nerves. Recent evidences however suggest that it may have an extended spectrum and a variable course. Objective: To describe various clinical features and pathogenesis of Mobius syndrome. Patients : Clinical profile of three patients with diverse manifestations of Mobius syndrome from a university teaching hospital in South India. Results: The presenting manifestations in the three patients with Mobius syndrome were mono-ocular visual impairment due to ischemic cerebrovascular disease (Patient 1, generalized tonic clonic seizures, delayed speech, bilateral facial, eighth and vagus nerve palsy (Patient 2 and progressive cranial polyneuropathy (Patient 3. Besides disorder of ocular mobility these patients had evidence of multiple morphologic abnormalities viz- polydactyly, high arched palate, clinodactyly, absence of pectoralis major and thoracic scoliosis. CT/MR imaging of the brainstem region were normal. The child with progressive involvement of multiple cranial nerve, and normal imaging of brain particularly posed diagnostic difficulty. Conclusion: Mobius syndrome is perhaps a regional development disorder of the entire brainstem with diverse clinical manifestations, severity and course, depending on the structures involved. Our observation, similar to the other reports, suggest that there is a need to further explore the etiology and pathogenetic link with other morphological abnormalities.

  9. A case of Bickerstaff's brainstem encephalitis in childhood

    Directory of Open Access Journals (Sweden)

    Ji Youn Kim

    2010-04-01

    Full Text Available Bickerstaff's brainstem encephalitis (BBE is a rare disease diagnosed by specific clinical features such as 'progressive, relatively symmetric external ophthalmoplegia and ataxia by 4 weeks' and 'disturbance of consciousness or hyperreflexia' after the exclusion of other diseases involving the brain stem. Anti-ganglioside antibodies (GM, GD and GQ in the serum or cerebrospinal fluid (CSF are sometimes informative for the diagnosis of BBE because of the rarity of positive findings in other diagnositic methods: brain magnetic resonance imaging (MRI, routine CSF examination, motor nerve conduction study, and needle electromyography. We report a rare case of childhood BBE with elevated anti-GM1 antibodies in the serum, who had specific clinical symptoms such as a cranial polyneuropathy presenting as ophthalmoplegia, dysarthria, dysphagia, and facial weakness; progressive motor weakness; altered mental status; and ataxia. However, the brain MRI, routine CSF examination, nerve conduction studies, electromyography, somatosensory evoked potentials, and brainstem auditory evoked potentials were normal. BBE was suspected and the patient was successfully treated with intravenous immunoglobulins.

  10. The effect of pH and operation mode for COD removal of slaughterhouse wastewater with Anaerobic Batch Reactor (ABR

    Directory of Open Access Journals (Sweden)

    Maria Octoviane Dyan

    2015-01-01

    Full Text Available Disposal of industrial wastes in large quantities was not in accordance with today's standards of waste into environmental issues that must be overcome with proper treatment. Similarly, the abattoir wastewater that contains too high organic compounds and suspended solids. The amount of liquid waste disposal Slaughterhouse (SW with high volume also causes pollution. The research aim to resolve this problem by lowering the levels of BOD-COD to comply with effluent quality standard. Anaerobic process is the right process for slaughterhouse wastewater treatment because of high content of organic compounds that can be utilized by anaerobic bacteria as a growth medium. Some research has been conducted among abattoir wastewater treatment using anaerobic reactors such as ABR, UASB and ASBR. Our research focuses on the search for the optimum results decline effluent COD levels to match the quality standards limbah and cow rumen fluid with biodigester ABR (Anaerobic Batch Reactor. The variables used were PH of 6, 7, and 8, as well as the concentration ratio of COD: N is 400:7; 450:7, and 500:7. COD value is set by the addition of N derived from urea [CO(NH2 2]. COD levels will be measured daily by water displacement technique. The research’s result for 20 days seen that optimum PH for biogas production was PH 7,719 ml. The optimum PH for COD removal is PH 6, 72.39 %. The operation mode COD:N for biogas production and COD removal is 500:7, with the production value is 601 ml and COD removal value is 63.85 %. The research’s conclusion, the PH optimum for biogas production was PH 7, then the optimum PH for COD removal is PH 6. The optimum operation mode COD:N for biogas production and COD removal was 500:7

  11. The Role of the Auditory Brainstem in Processing Linguistically-Relevant Pitch Patterns

    Science.gov (United States)

    Krishnan, Ananthanarayan; Gandour, Jackson T.

    2009-01-01

    Historically, the brainstem has been neglected as a part of the brain involved in language processing. We review recent evidence of language-dependent effects in pitch processing based on comparisons of native vs. nonnative speakers of a tonal language from electrophysiological recordings in the auditory brainstem. We argue that there is enhancing…

  12. Tasquinimod (ABR-215050, a quinoline-3-carboxamide anti-angiogenic agent, modulates the expression of thrombospondin-1 in human prostate tumors

    Directory of Open Access Journals (Sweden)

    Isaacs John T

    2010-05-01

    Full Text Available Abstract Background The orally active quinoline-3-carboxamide tasquinimod [ABR-215050; CAS number 254964-60-8, which currently is in a phase II-clinical trial in patients against metastatic prostate cancer, exhibits anti-tumor activity via inhibition of tumor angiogenesis in human and rodent tumors. To further explore the mode of action of tasquinimod, in vitro and in vivo experiments with gene microarray analysis were performed using LNCaP prostate tumor cells. The array data were validated by real-time semiquantitative reversed transcriptase polymerase chain reaction (sqRT-PCR and protein expression techniques. Results One of the most significant differentially expressed genes both in vitro and in vivo after exposure to tasquinimod, was thrombospondin-1 (TSP1. The up-regulation of TSP1 mRNA in LNCaP tumor cells both in vitro and in vivo correlated with an increased expression and extra cellular secretion of TSP1 protein. When nude mice bearing CWR-22RH human prostate tumors were treated with oral tasquinimod, there was a profound growth inhibition, associated with an up-regulation of TSP1 and a down- regulation of HIF-1 alpha protein, androgen receptor protein (AR and glucose transporter-1 protein within the tumor tissue. Changes in TSP1 expression were paralleled by an anti-angiogenic response, as documented by decreased or unchanged tumor tissue levels of VEGF (a HIF-1 alpha down stream target in the tumors from tasquinimod treated mice. Conclusions We conclude that tasquinimod-induced up-regulation of TSP1 is part of a mechanism involving down-regulation of HIF1α and VEGF, which in turn leads to reduced angiogenesis via inhibition of the "angiogenic switch", that could explain tasquinimods therapeutic potential.

  13. The role of the auditory brainstem in processing musically-relevant pitch

    Directory of Open Access Journals (Sweden)

    Gavin M. Bidelman

    2013-05-01

    Full Text Available Neuroimaging work has shed light on the cerebral architecture involved in processing the melodic and harmonic aspects of music. Here, recent evidence is reviewed illustrating that subcortical auditory structures contribute to the early formation and processing of musically-relevant pitch. Electrophysiological recordings from the human brainstem and population responses from the auditory nerve reveal that nascent features of tonal music (e.g., consonance/dissonance, pitch salience, harmonic sonority are evident at early, subcortical levels of the auditory pathway. The salience and harmonicity of brainstem activity is strongly correlated with listeners’ perceptual preferences and perceived consonance for the tonal relationships of music. Moreover, the hierarchical ordering of pitch intervals/chords described by the Western music practice and their perceptual consonance is well-predicted by the salience with which pitch combinations are encoded in subcortical auditory structures. While the neural correlates of consonance can be tuned and exaggerated with musical training, they persist even in the absence of musicianship or long-term enculturation. As such, it is posited that the structural foundations of musical pitch might result from innate processing performed by the central auditory system. A neurobiological predisposition for consonant, pleasant sounding pitch relationships may be one reason why these pitch combinations have been favored by composers and listeners for centuries. It is suggested that important perceptual dimensions of music emerge well before the auditory signal reaches cerebral cortex and prior to attentional engagement. While cortical mechanisms are no doubt critical to the perception, production, and enjoyment of music, the contribution of subcortical structures implicates a more integrated, hierarchically organized network underlying music processing within the brain.

  14. Autonomic correlations with MRI are abnormal in the brainstem vasomotor centre in Chronic Fatigue Syndrome

    Directory of Open Access Journals (Sweden)

    Leighton R. Barnden

    2016-01-01

    Full Text Available Autonomic changes are often associated with the chronic fatigue syndrome (CFS, but their pathogenetic role is unclear and brain imaging investigations are lacking. The vasomotor centre and, through it, nuclei in the midbrain and hypothalamus play a key role in autonomic nervous system regulation of steady state blood pressure (BP and heart rate (HR. In this exploratory cross-sectional study, BP and HR, as indicators of autonomic function, were correlated with volumetric and T1- and T2-weighted spin-echo (T1w and T2w brain MRI in 25 CFS subjects and 25 normal controls (NC. Steady state BP (systolic, diastolic and pulse pressure and HR in two postures were extracted from 24 h blood pressure monitoring. We performed (1 MRI versus autonomic score interaction-with-group regressions to detect locations where regression slopes differed in the CFS and NC groups (collectively indicating abnormality in CFS, and (2 MRI regressions in the CFS and NC groups alone to detect additional locations with abnormal correlations in CFS. Significant CFS regressions were repeated controlling for anxiety and depression (A&D. Abnormal regressions were detected in nuclei of the brainstem vasomotor centre, midbrain reticular formation and hypothalamus, but also in limbic nuclei involved in stress responses and in prefrontal white matter. Group comparisons of CFS and NC did not find MRI differences in these locations. We propose therefore that these regulatory nuclei are functioning correctly, but that two-way communication between them is impaired in CFS and this affects signalling to/from peripheral effectors/sensors, culminating in inverted or magnified correlations. This single explanation for the diverse abnormal correlations detected here consolidates the conclusion for a brainstem/midbrain nerve conduction deficit inferred earlier (Barnden et al., 2015. Strong correlations were also detected in isolated NC regressions.

  15. Tractography of the brainstem in major depressive disorder using diffusion tensor imaging.

    Directory of Open Access Journals (Sweden)

    Yun Ju C Song

    Full Text Available BACKGROUND: The brainstem is the main region that innervates neurotransmitter release to the Hypothalamic-Pituitary Adrenal (HPA axis and fronto-limbic circuits, two key brain circuits found to be dysfunctional in Major Depressive Disorder (MDD. However, the brainstem's role in MDD has only been evaluated in limited reports. Using Diffusion Tensor Imaging (DTI, we investigated whether major brainstem white matter tracts that relate to these two circuits differ in MDD patients compared to healthy controls. METHODS: MDD patients (n = 95 and age- and gender-matched controls (n = 34 were assessed using probabilistic tractography of DTI to delineate three distinct brainstem tracts: the nigrostriatal tract (connecting brainstem to striatum, solitary tract (connecting brainstem to amygdala and corticospinal tract (connecting brainstem to precentral cortex. Fractional anisotropy (FA was used to measure the white matter integrity of these tracts, and measures were compared between MDD and control participants. RESULTS: MDD participants were characterized by a significant and specific decrease in white matter integrity of the right solitary tract (p<0.009 using independent t-test, which is a "bottom up" afferent pathway that connects the brainstem to the amygdala. This decrease was not related to symptom severity. CONCLUSIONS: The results provide new evidence to suggest that structural connectivity between the brainstem and the amygdala is altered in MDD. These results are interesting in light of predominant theories regarding amygdala-mediated emotional reactivity observed in functional imaging studies of MDD. The characterization of altered white matter integrity in the solitary tract in MDD supports the possibility of dysfunctional brainstem-amygdala connectivity impacting vulnerable circuits in MDD.

  16. Audiometria de tronco encefálico (abr: o uso do mascaramento na avaliação de indivíduos portadores de perda auditiva unilateral

    Directory of Open Access Journals (Sweden)

    Toma Melissa M. T.

    2003-01-01

    Full Text Available A necessidade do mascaramento na avaliação da audição por meio da ABR ainda é um assunto consideravelmente debatido (Durrant & Ferraro, 2001. OBJETIVO: O presente estudo propôs investigar a necessidade do mascaramento contralateral, empregado na orelha normal, ao realizar a ABR em indivíduos portadores de perda auditiva neurossensorial unilateral. FORMA DE ESTUDO: Clínico prospectivo. MATERIAL E MÉTODO: A amostra constituiu-se de 22 indivíduos portadores de perda auditiva neurossensorial unilateral de grau profundo, sendo 10 do sexo feminino e 12 do sexo masculino, com idades variando entre 9 e 44 anos. Todos os indivíduos foram submetidos a: audiometria tonal liminar, logoaudiometria (SRT, IPRF e SDT, medidas de imitância acústica (incluindo a pesquisa dos reflexos acústicos - modo ipsilateral e contralateral e audiometria de tronco encefálico na ausência e na presença do mascaramento. RESULTADOS: Todos os indivíduos apresentaram perda auditiva neurossensorial unilateral de grau profundo e curvas timpanométricas do tipo A bilateralmente. Na avaliação da ABR, 100% da amostra apresentou presença da Onda V na orelha comprometida, sendo que ao introduzir o mascaramento contralateral tais respostas não foram observadas. CONCLUSÕES: O mascaramento é um procedimento necessário para a avaliação da audição por meio da ABR em indivíduos portadores de perdas auditivas unilaterais, visando a obtenção de resultados fidedignos. Na ABR, a atenuação interaural para clicks foi maior (65 dB do que a observada na audiometria tonal liminar, sendo necessário, portanto, uma menor intensidade de mascaramento para eliminar a resposta da via auditiva contralateral.

  17. Dilated Virchow–Robin spaces mimicking a brainstem arteriovenous malformation

    Directory of Open Access Journals (Sweden)

    Thomas J Buell

    2017-01-01

    Full Text Available Virchow–Robin spaces (VRS are ubiquitous and commonly observed as the resolution of magnetic resonance imaging (MRI continues to improve. The function of VRS and the etiology of their dilation is still a subject of research. Diagnosing dilated VRS (dVRS can be challenging because they may appear similar to other pathologies such as cystic neoplasms, infectious cysts, and even arteriovenous malformations (AVMs on certain MRI pulse sequences. We reported a unique case of brainstem dVRS mimicking an AVM. Furthermore, the extensive pontine involvement of our patient's lesion is rarely described in neurosurgical literature. Understanding the imaging characteristics of dVRS is critical to accurately diagnose these lesions and avoid unnecessary tests and procedures.

  18. The brainstem efferent acoustic chiasm in pigmented and albino rats.

    Science.gov (United States)

    Reuss, Stefan; Closhen-Gabrisch, Stefanie; Closhen, Christina

    2016-02-01

    The present study examined whether structural peculiarities in the brain-efferent pathway to the organ of Corti may underlie functional differences in hearing between pigmented and albino individuals of the same mammalian species. Pigmented Brown-Norway rats and albino Wistar rats received unilateral injections of an aqueous solution of the retrograde neuronal tracer Fluorogold (FG) into the scala tympani of the cochlea to identify olivocochlear neurons (OCN) in the brainstem superior olivary complex. After five days, brains were perfusion-fixed and brainstem sections were cut and analyzed with respect to retrogradely labeled neurons. Intrinsic neurons of the lateral system were located exclusively in the ipsilateral lateral superior olive (LSO) in both groups. Shell neurons surrounding the LSO and in periolivary regions, which made up only 5-8% of all OCN, were more often contralaterally located in albino than in pigmented animals. A striking difference was observed in the laterality of neurons of the medial olivocochlear (MOC) system, which provided more than one third of all OCN. These neurons, located in the rostral periolivary region and in the ventral nucleus of the trapezoid body, were observed contralateral to 45% in pigmented and to 68% in albino animals. Our study, the first to compare the origin of the olivocochlear bundle in pigmented and albino rats, provides evidence for differences in the crossing pattern of the olivocochlear pathway. These were found predominantly in the MOC system providing the direct efferent innervation of cochlear outer hair cells. Our findings may account for the alterations in auditory perception observed in albino mammals including man. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Frontal-Brainstem Pathways Mediating Placebo Effects on Social Rejection.

    Science.gov (United States)

    Koban, Leonie; Kross, Ethan; Woo, Choong-Wan; Ruzic, Luka; Wager, Tor D

    2017-03-29

    Placebo treatments can strongly affect clinical outcomes, but research on how they shape other life experiences and emotional well-being is in its infancy. We used fMRI in humans to examine placebo effects on a particularly impactful life experience, social pain elicited by a recent romantic rejection. We compared these effects with placebo effects on physical (heat) pain, which are thought to depend on pathways connecting prefrontal cortex and periaqueductal gray (PAG). Placebo treatment, compared with control, reduced both social and physical pain, and increased activity in the dorsolateral prefrontal cortex (dlPFC) in both modalities. Placebo further altered the relationship between affect and both dlPFC and PAG activity during social pain, and effects on behavior were mediated by a pathway connecting dlPFC to the PAG, building on recent work implicating opioidergic PAG activity in the regulation of social pain. These findings suggest that placebo treatments reduce emotional distress by altering affective representations in frontal-brainstem systems. SIGNIFICANCE STATEMENT Placebo effects are improvements due to expectations and the socio-medical context in which treatment takes place. Whereas they have been extensively studied in the context of somatic conditions such as pain, much less is known of how treatment expectations shape the emotional experience of other important stressors and life events. Here, we use brain imaging to show that placebo treatment reduces the painful feelings associated with a recent romantic rejection by recruiting a prefrontal-brainstem network and by shifting the relationship between brain activity and affect. Our findings suggest that this brain network may be important for nonspecific treatment effects across a wide range of therapeutic approaches and mental health conditions. Copyright © 2017 the authors 0270-6474/17/373621-11$15.00/0.

  20. Working memory capacity and visual-verbal cognitive load modulate auditory-sensory gating in the brainstem: toward a unified view of attention.

    Science.gov (United States)

    Sörqvist, Patrik; Stenfelt, Stefan; Rönnberg, Jerker

    2012-11-01

    Two fundamental research questions have driven attention research in the past: One concerns whether selection of relevant information among competing, irrelevant, information takes place at an early or at a late processing stage; the other concerns whether the capacity of attention is limited by a central, domain-general pool of resources or by independent, modality-specific pools. In this article, we contribute to these debates by showing that the auditory-evoked brainstem response (an early stage of auditory processing) to task-irrelevant sound decreases as a function of central working memory load (manipulated with a visual-verbal version of the n-back task). Furthermore, individual differences in central/domain-general working memory capacity modulated the magnitude of the auditory-evoked brainstem response, but only in the high working memory load condition. The results support a unified view of attention whereby the capacity of a late/central mechanism (working memory) modulates early precortical sensory processing.

  1. Changes in pitch height elicit both language-universal and language-dependent changes in neural representation of pitch in the brainstem and auditory cortex.

    Science.gov (United States)

    Krishnan, Ananthanarayan; Suresh, Chandan H; Gandour, Jackson T

    2017-03-27

    Language experience shapes encoding of pitch-relevant information at both brainstem and cortical levels of processing. Pitch height is a salient dimension that orders pitch from low to high. Herein we investigate the effects of language experience (Chinese, English) in the brainstem and cortex on (i) neural responses to variations in pitch height, (ii) presence of asymmetry in cortical pitch representation, and (iii) patterns of relative changes in magnitude of pitch height between these two levels of brain structure. Stimuli were three nonspeech homologs of Mandarin Tone 2 varying in pitch height only. The frequency-following response (FFR) and the cortical pitch-specific response (CPR) were recorded concurrently. At the Fz-linked T7/T8 site, peak latency of Na, Pb, and Nb decreased with increasing pitch height for both groups. Peak-to-peak amplitude of Na-Pb and Pb-Nb increased with increasing pitch height across groups. A language-dependent effect was restricted to Na-Pb; the Chinese had larger amplitude than the English group. At temporal sites (T7/T8), the Chinese group had larger amplitude, as compared to English, across stimuli, but also limited to the Na-Pb component and right temporal site. In the brainstem, F0 magnitude decreased with increasing pitch height; Chinese had larger magnitude across stimuli. A comparison of CPR and FFR responses revealed distinct patterns of relative changes in magnitude common to both groups. CPR amplitude increased and FFR amplitude decreased with increasing pitch height. Experience-dependent effects on CPR components vary as a function of neural sensitivity to pitch height within a particular temporal window (Na-Pb). Differences between the auditory brainstem and cortex imply distinct neural mechanisms for pitch extraction at both levels of brain structure. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. Changes in pitch height elicit both language universal and language dependent changes in neural representation of pitch in the brainstem and auditory cortex

    Science.gov (United States)

    Krishnan, Ananthanarayan; Suresh, Chandan H.; Gandour, Jackson T.

    2017-01-01

    Language experience shapes encoding of pitch-relevant information at both brainstem and cortical levels of processing. Pitch height is a salient dimension that orders pitch from low to high. Herein we investigate the effects of language experience (Chinese, English) in the brainstem and cortex on i) neural responses to variations in pitch height, ii) presence of asymmetry in cortical pitch representation, and iii) patterns of relative changes in magnitude of pitch height between these two levels of brain structure. Stimuli were three nonspeech homologs of Mandarin Tone 2 varying in pitch height only. The frequency-following response (FFR) and the cortical pitch-specific response (CPR) were recorded concurrently. At the Fz-linked T7/T8 site, peak latency of Na, Pb, and Nb decreased with increasing pitch height for both groups. Peak-to-peak amplitude of Na–Pb and Pb–Nb increased with increasing pitch height across groups. A language-dependent effect was restricted to Na-Pb; the Chinese had larger amplitude than the English group. At temporal sites (T7/T8), the Chinese group had larger amplitude, as compared to English, across stimuli, but also limited to the Na-Pb component and right temporal site. In the brainstem, F0 magnitude decreased with increasing pitch height; Chinese had larger magnitude across stimuli. A comparison of CPR and FFR responses revealed distinct patterns of relative changes in magnitude common to both groups. CPR amplitude increased and FFR amplitude decreased with increasing pitch height. Experience-dependent effects on CPR components vary as a function of neural sensitivity to pitch height within a particular temporal window (Na–Pb). Differences between the auditory brainstem and cortex imply distinct neural mechanisms for pitch extraction at both levels of brain structure. PMID:28108254

  3. A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

    Directory of Open Access Journals (Sweden)

    Xiujuan Fu

    2017-12-01

    Full Text Available Although the function of the cerebellum in neurocognition has been well-documented, the similar role of the brainstem has yet to be fully elucidated. This clinical research study aimed to combine data relating to neuropsychological assessments and P300 to explore cognitive dysfunction and affective impairment following brainstem stroke. Thirty-four patients with isolated brainstem stroke and twenty-six healthy controls were recruited; for each patient, we collated data pertaining to the P300, Addenbrooke's Cognitive Examination III (ACE-III, Montreal Cognitive Assessment Chinese version (MoCA, trail-making test (TMT, Symbol Digit Modalities Test (SDMT, Wechsler Adult Intelligence Scale-Digit Spans (DS, Stroop test, Self Rating Depression Scale (SDS, and Self Rating Anxiety Scale (SAS. Significance was analyzed using an independent T-test or the Mann-Whitney U-test. Correlation was analyzed using Pearson's correlation analysis or Spearman's correlation analysis. Collectively, data revealed that brainstem stroke caused mild cognitive impairment (MCI, and that visuospatial, attention, linguistic, and emotional disturbances may occur after isolated brainstem stroke. Cognitive decline was linked to P300 latency, ACE-III, and MoCA; P300 latency was correlated with ACE-III. Patients with right brainstem lesions were more likely to suffer memory decline. The present study provides initial data relating to the role of the brainstem in neurocognition, and will be useful for further understanding of vascular cognitive and affective impairment.

  4. Inverse activity of masticatory muscles with and without trismus: a brainstem syndrome.

    Science.gov (United States)

    Jelasic, F; Freitag, V

    1978-01-01

    Clinical and EMG findings in 10 cases of intrinsic brainstem lesions are reported with paradoxical activity of jaw closing muscles during jaw opening, with and without trismus. In five cases with trigeminal anaesthesia, the inverse activity of jaw closers is interpreted as a manifestation of disturbance in the central programming of mastication in the motor trigeminal area of the brainstem. Stretch reflex mechanisms and disinhibition of the trigeminal motor neurones play no part in the origin of inverse activity. The distinct brainstem syndrome can only be detected by EMG and the special clinical features. Images PMID:690651

  5. Auditory Brain-Stem and Middle-and Long-Latency Evoked Potentials in Coma

    OpenAIRE

    Rosenberg, C; Wogensen, K; Starr, A

    1984-01-01

    Twenty-five patients in coma, each with a Glascow Coma Scale measure less than or equal to five, were studied within the first three days of hospitalization with auditory brain-stem and middle- and long-latency evoked potentials. Survival was related to the simultaneous preservation of long- and middle-latency and brain-stem evoked potentials. The preservation of just middle-latency and/or brain-stem components did not correlate with survival. However, if the group of patients in coma due to ...

  6. Stereotactic biopsy for brainstem lesion: Comparison of approaches and reports of 10 cases

    Directory of Open Access Journals (Sweden)

    Se-Yi Chen

    2011-03-01

    Conclusion: A number of approaches are available for stereotactic brainstem biopsy. Surgical approach should be tailored, according to the location neurological function, with special concern for the patients’ safety. In selected condition, frameless stereotaxy biopsy also provides competed diagnostic yield.

  7. Organization of diencephalic and brainstem afferent projections to the lateral septum in the rat

    NARCIS (Netherlands)

    Luiten, Paul G.M.; Kuipers, Folkert; Schuitmaker, Hans

    1982-01-01

    Ascending diencephalic and brainstem afferents to the lateral septal column were studied by retrograde transport of horseradish peroxidase following microiontophoretic injections in the various subdivisions of the lateral septal area. Predominantly ispilateral cells, of which several coincide with

  8. Herpetic brainstem encephalitis: report of a post-mortem case studied electron microscopically and immunohisiochemically

    Directory of Open Access Journals (Sweden)

    José Eymard Homem Pitella

    1987-03-01

    Full Text Available A post-mortem examined case of herpetic brainstem encephalitis is presented. Clinically, the patient had cephalea followed by ataxia, drowsiness and multiple palsies of some cranial nerves, developing into death in eight days. The pathologic examination of the brain showed necrotizing encephalitis in multiple foci limited to the brainstem, more distinctly in the pons and medula oblongata. The technique of immunoperoxidase revealed rare glial cells with intranuclear immunoreactivity for herpes antigen. Rare viral particles with the morphological characteristics of the herpesvirus were identified in the nuclei of neurons in 10% formol fixed material. This is the second reported case of herpetic brainstem encephalitis confirmed by post-mortem examination. The pathway used by the virus to reach the central nervous system and its posterior dissemination to the oral cavity, the orbitofrontal region and the temporal lobes as well as to the brainstem, after a period of latency and reactivation, are discussed.

  9. DTI assessment of the brainstem white matter tracts in pediatric BSG before and after therapy: a report from the Pediatric Brain Tumor Consortium.

    Science.gov (United States)

    Prabhu, Sanjay P; Ng, Sarah; Vajapeyam, Sridhar; Kieran, Mark W; Pollack, Ian F; Geyer, Russell; Haas-Kogan, Daphne; Boyett, James M; Kun, Larry; Poussaint, Tina Young

    2011-01-01

    To assess changes in apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values in brainstem gliomas (BSG) in children and to observe the temporal evolution of changes in the white matter tracts following therapy using diffusion tensor imaging (DTI) analysis. Serial ADC and FA measurements were obtained in three patients with newly diagnosed BSG on two approved treatment protocols. Values were compared with a set of normative ADC, FA, and eigenvalues of age-matched children of the corticospinal, transverse pontine and medial lemniscal tracts. Fiber tracking of the tracts coursing through the brainstem was performed using standard diffusion tractography analysis. We found increased ADC values within tumor at baseline compared to age-matched controls, with subsequent drop following treatment and subsequent increase with recurrence. Correspondingly, FA values were reduced at presentation, but transiently recovered during the phase of tumor response to treatment, and finally decreased significantly during tumor progression. These changes were concordant with the tractography analysis of white matter tracts in the brainstem. Based on these results, we suggest that initial changes in ADC and FA values reflects tract infiltration by tumor, but not complete disruption, whereas tumor progression results in complete loss of anisotropy possibly due to tract disruption. Serial changes in ADC and FA values and tractography data in pediatric BSG suggest initial tumor infiltration, with transient improvement on treatment and subsequent loss of tract anisotropy during tumor progression. This technique may have potential use in assessing response to treatment regimens for pediatric BSG.

  10. A probabilistic atlas of human brainstem pathways based on connectome imaging data.

    Science.gov (United States)

    Tang, Yuchun; Sun, Wei; Toga, Arthur W; Ringman, John M; Shi, Yonggang

    2018-04-01

    The brainstem is a critical structure that regulates vital autonomic functions, houses the cranial nerves and their nuclei, relays motor and sensory information between the brain and spinal cord, and modulates cognition, mood, and emotions. As a primary relay center, the fiber pathways of the brainstem include efferent and afferent connections among the cerebral cortex, spinal cord, and cerebellum. While diffusion MRI has been successfully applied to map various brain pathways, its application for the in vivo imaging of the brainstem pathways has been limited due to inadequate resolution and large susceptibility-induced distortion artifacts. With the release of high-resolution data from the Human Connectome Project (HCP), there is increasing interest in mapping human brainstem pathways. Previous works relying on HCP data to study brainstem pathways, however, did not consider the prevalence (>80%) of large distortions in the brainstem even after the application of correction procedures from the HCP-Pipeline. They were also limited in the lack of adequate consideration of subject variability in either fiber pathways or region of interests (ROIs) used for bundle reconstruction. To overcome these limitations, we develop in this work a probabilistic atlas of 23 major brainstem bundles using high-quality HCP data passing rigorous quality control. For the large-scale data from the 500-Subject release of HCP, we conducted extensive quality controls to exclude subjects with severe distortions in the brainstem area. After that, we developed a systematic protocol to manually delineate 1300 ROIs on 20 HCP subjects (10 males; 10 females) for the reconstruction of fiber bundles using tractography techniques. Finally, we leveraged our novel connectome modeling techniques including high order fiber orientation distribution (FOD) reconstruction from multi-shell diffusion imaging and topography-preserving tract filtering algorithms to successfully reconstruct the 23 fiber bundles

  11. Prodominant hypertensive brainstem encephalopathy with supratentorial involvement: Case report and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Hee; Park, Sung Tae; Lim, Hyun Kyung [Dept. of Radiology, Soonchunhyang University Hospital, Soonchunhyang University School of Medicine, Seoul (Korea, Republic of); Kim, Sung Tae; Cha, Ji Hoon [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2014-12-15

    Hypertensive encephalopathy typically presents with bilateral parietooccipital vasogenic edema. Brainstem and cerebellar edema are uncommon in association with typical supratentorial changes. We experienced three cases of atypical hypertensive encephalopathy involving brainstem and cerebellum as well as cerebral white matter, which showed characteristic alternating linear bright and low signals in the pons, the so-called 'stripe sign'. We report these cases here with a brief literature review.

  12. Combined CMV- and HSV-1 brainstem encephalitis restricted to medulla oblongata.

    Science.gov (United States)

    Katchanov, J; Branding, G; Stocker, H

    2014-04-15

    We report a very rare case of a combined CMV- and HSV-1 isolated brainstem encephalitis restricted to medulla oblongata in a patient with advanced HIV disease. Neither limbic nor general ventricular involvement was detected on neuroimaging. The case highlights the importance of testing for HSV-1 and CMV in HIV-infected patients presenting with an isolated brainstem syndrome. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Brainstem acoustic areas in the marine catfish, Arius felis.

    Science.gov (United States)

    McCormick, C A

    2001-03-01

    The marine catfish Arius felis produces low frequency sounds for communication and obstacle detection. It was hypothesized that the utriculus of the inner ear might play an important role in these behaviors. In the current study, brainstem acoustic areas were studied to reveal possible neuroanatomical specializations in utricular processing areas. The first-order octaval nuclei in Arius were identical in number, anatomical characteristics, and organization of saccular, lagenar, and utricular inputs to previous reports of these features in Ictalurus, a closely related species of catfish that does not exhibit the specialized acoustic behaviors present in Arius. Similarly, injections of neural tracer in the acoustic midbrain (nucleus centralis) of Arius revealed afferent and retrograde pathways almost identical to those previously reported in Ictalurus. It is suggested that areas within the primary and higher-order octaval nuclei that utilize utricular input in acoustic processing are likely identical in Arius and Ictalurus. Two sets of higher-order connections in Arius differ from those in Ictalurus. First, Arius apparently lacks the direct input from the anterior octaval nucleus to nucleus centralis reported in Ictalurus. Second, in Arius nucleus centralis projects bilaterally to a strip of neurons positioned ventral to the ventral boundary of the torus semicircularis. This projection is apparently absent in Ictalurus and in the related species Carassius (goldfish), but has been previously reported in Porichthyes, a sound-producing species belonging to a different teleost taxon. Copyright 2001 S. Karger AG, Basel

  14. CT findings of traumatic primary brain-stem injury

    International Nuclear Information System (INIS)

    Hosaka, Yasuaki; Hatashita, Shizuo; Bandou, Kuniaki; Ueki, Yasuyuki; Abe, Kouzou; Koga, Nobunori; Sugimura, Jun; Sakakibara, Tokiwa; Takagi, Suguru

    1984-01-01

    A series of 27 consecutive patients with traumatic primary brain stem injuries was studied. They were diagnosed by means of clinical signs, neurological examination, and computerized tomography (CT). The CT findings of the brain-stem lesions were classified into 4 types: Type H, spotty, high-density; Type H and L, high- and low-densities; Type L, low-density; Type I, isodensity. The Glasgow coma scale (GCS), neurological findings on admission, CT findings (findings in the brain stem, obliteration of perimesencephalic cistern (PMC), and other findings), and the Glasgow outcome scale (GOS) were examined. In the 9 cases of Type H, there was a correlation between the GCS and the GOS, and the spotty, high-density lesions were localized mainly in the dorsal and/or ventral midbrain parenchyma, but these lesions did not show focal signs and symptoms. Without an obliteration of the PMC, Type-H patients did not always have a bad outcome. In the 4 cases of Type H and L, the 2 cases of Type L, and the 12 cases of Type I, there was an obliteration of the PMC. All of the these cases had a bad outcome (1 case of moderate disability, 3 cases of severe disability, and 14 cases of death). The mechanism producing a spotty, high-density area was discussed. The weaker impact (than the other types) and individual anatomical differences weresupposed to make for a spotty, high-density are in the brain stem. (author)

  15. Brainstem auditory evoked potentials in children with lead exposure

    Directory of Open Access Journals (Sweden)

    Katia de Freitas Alvarenga

    2015-02-01

    Full Text Available Introduction: Earlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated. Objective: To investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test. Methods: Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months ± 3 years, 2 months. Results: The mean time-integrated cumulative blood lead index was 12 µg/dL (SD ± 5.7, range:2.433. All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I-III, III-V, and I-V, and the cumulative lead values. Conclusion: No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area.

  16. A clinical study of brainstem infarction identified on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masaki; Takahashi, Akira (Nagoya Univ. (Japan). Faculty of Medicine); Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro

    1993-04-01

    We conducted a clinical study of 155 cases that were confirmed to have brainstem infarctions on MRI (T[sub 1]-weighted image showed a low signal and T[sub 2]-weighted image showed a high signal, measuring in excess of 2 x 2 mm). The majority of the brainstem infarction was located in the pontine base in 132 cases (85.2%). Of these, 19 cases had double lesions including infarctions in the pontine base. Second infarctions frequently occurred in the cerebral peduncle or medical medulla oblongata, unilateral to the pontine infarctions. In addition to 98 symptomatic cases, there were 57 cases of 'asymptomatic' brainstem infarction. They comprised 24 cases accompanying other symptomatic cerebrovascular diseases in the supratentorium and 33 cases of transient subjective complaints such as headache or vertigo-dizziness. Complication by supratentorial infarctions was significantly frequent in cases of brainstem infarction (p<0.001), 122 of 155 cases (78.7%), especially in the pontine base (88.6%); while in the control cases (without brainstem infarction) only 65 of 221 cases (29.4%). These findings are considered to show the widespread progress of arteriosclerosis in brainstem infarction, especially in ones in the pontine base. (author).

  17. [Distribution of human enterovirus 71 in brainstem of infants with brain stem encephalitis and infection mechanism].

    Science.gov (United States)

    Hao, Bo; Gao, Di; Tang, Da-Wei; Wang, Xiao-Guang; Liu, Shui-Ping; Kong, Xiao-Ping; Liu, Chao; Huang, Jing-Lu; Bi, Qi-Ming; Quan, Li; Luo, Bin

    2012-04-01

    To explore the mechanism that how human enterovirus 71 (EV71) invades the brainstem and how intercellular adhesion molecules-1 (ICAM-1) participates by analyzing the expression and distribution of human EV71, and ICAM-1 in brainstem of infants with brain stem encephalitis. Twenty-two brainstem of infants with brain stem encephalitis were collected as the experimental group and 10 brainstems of fatal congenital heart disease were selected as the control group. The sections with perivascular cuffings were selected to observe EV71-VP1 expression by immunohistochemistry method and ICAM-1 expression was detected for the sections with EV71-VP1 positive expression. The staining image analysis and statistics analysis were performed. The experiment and control groups were compared. (1) EV71-VP1 positive cells in the experimental group were mainly astrocytes in brainstem with nigger-brown particles, and the control group was negative. (2) ICAM-1 positive cells showed nigger-brown. The expression in inflammatory cells (around blood vessels of brain stem and in glial nodules) and gliocytes increased. The results showed statistical difference comparing with control group (P diagnose fatal EV71 infection in infants. EV71 can invade the brainstem via hematogenous route. ICAM-1 may play an important role in the pathogenic process.

  18. Imaging of glial cell morphology, SOD1 distribution and elemental composition in the brainstem and hippocampus of the ALS hSOD1G93A rat.

    Science.gov (United States)

    Stamenković, Stefan; Dučić, Tanja; Stamenković, Vera; Kranz, Alexander; Andjus, Pavle R

    2017-08-15

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder affecting motor and cognitive domains of the CNS. Mutations in the Cu,Zn-superoxide dismutase (SOD1) cause 20% of familial ALS and provoke formation of intracellular aggregates and copper and zinc unbinding, leading to glial activation and neurodegeneration. Therefore, we investigated glial cell morphology, intracellular SOD1 distribution, and elemental composition in the brainstem and hippocampus of the hSOD1 G93A transgenic rat model of ALS. Immunostaining for astrocytes, microglia and SOD1 revealed glial proliferation and progressive tissue accumulation of SOD1 in both brain regions of ALS rats starting already at the presymptomatic stage. Glial cell morphology analysis in the brainstem of ALS rats revealed astrocyte activation occurring before disease symptoms onset, followed by activation of microglia. Hippocampal ALS astrocytes exhibited an identical reactive profile, while microglial morphology was unchanged. Additionally, ALS brainstem astrocytes demonstrated progressive SOD1 accumulation in the cell body and processes, while microglial SOD1 levels were reduced and its distribution limited to distal cell processes. In the hippocampus both glial cell types exhibited SOD1 accumulation in the cell body. X-ray fluorescence imaging revealed decreased P and increased Ca, Cl, K, Ni, Cu and Zn in the brainstem, and higher levels of Cl, Ni and Cu, but lower levels of Zn in the hippocampus of symptomatic ALS rats. These results bring new insights into the glial response during disease development and progression in motor as well as in non-motor CNS structures, and indicate disturbed tissue elemental homeostasis as a prominent hallmark of disease pathology. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Role of sex hormones produced during menstrual cycle on brainstem encoding of speech stimulus.

    Science.gov (United States)

    Prabhu, Prashanth; Banerjee, Neha; Anil, Arya; Abdulla, Asma

    2016-11-01

    There are no studies attempted to determine the effects of different phases of menstrual cycle on frequency following response (FFR) for speech stimuli. The aim of the study was to determine the differences in latencies and amplitude of FFR waves recorded at four phases of menstrual cycle. In addition, it was also attempted to determine if there is any ear effect on latency and amplitude measures across the phases of menstrual cycle. FFR was recorded in 20 females in the age range of 18-25 years in the four menstrual cycles [Phase I-menses (day 1-3), Phase II-proliferative phase (day 11-14), Phase III-mid-luteal phase (day 17-22) and Phase IV-pre-menstrual phase (day 25-27)]. The results of the study showed that there was significant reduction in latencies and slight increase in amplitude during menses and mid-luteal phase compared to mid-cycle and pre-menstruation cycles. The present study supports the hypothesis that difference in the levels of sex hormones in women during menstrual cycle can affect brainstem encoding of speech stimuli.

  20. Diffusion tensor imaging of the inferior colliculus and brainstem auditory-evoked potentials in preterm infants

    International Nuclear Information System (INIS)

    Reiman, Milla; Lehtonen, Liisa; Lapinleimu, Helena; Parkkola, Riitta; Johansson, Reijo; Jaeaeskelaeinen, Satu K.; Kujari, Harry; Haataja, Leena

    2009-01-01

    Preterm and low-birth-weight infants have an increased risk of sensorineural hearing loss. Brainstem auditory-evoked potentials (BAEP) are an effective method to detect subtle deficits in impulse conduction in the auditory pathway. Abnormalities on diffusion tensor imaging (DTI) have been shown to be associated with perinatal white-matter injury and reduced fractional anisotropy (FA) has been reported in patients with sensorineural hearing loss. To evaluate the possibility of a correlation between BAEP and DTI of the inferior colliculus in preterm infants. DTI at term age and BAEP measurements were performed on all very-low-birth-weight or very preterm study infants (n=56). FA and apparent diffusion coefficient (ADC) of the inferior colliculus were measured from the DTI. Shorter BAEP wave I, III, and V latencies and I-III and I-V intervals and higher wave V amplitude correlated with higher FA of the inferior colliculus. The association between the DTI findings of the inferior colliculus and BAEP responses suggests that DTI can be used to assess the integrity of the auditory pathway in preterm infants. (orig.)

  1. Curcumin decreases astrocytic reaction after gliotoxic injury in the rat brainstem

    Directory of Open Access Journals (Sweden)

    Eduardo Bondan

    Full Text Available ABSTRACT Recent studies have demonstrated that curcumin (Cur has antioxidant, anti-inflammatory and anti-fibrotic effects. Ethidium bromide (EB injections into the central nervous system (CNS are known to induce local oligodendroglial and astrocytic loss, resulting in primary demyelination and neuroinflammation. Peripheral astrogliosis is seen around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP. This investigation aimed to evaluate the effect of Cur administration on astrocytic response following gliotoxic injury. Wistar rats were injected with EB into the cisterna pontis and treated, or not, with Cur (100 mg/kg/day, intraperitoneal route during the experimental period. Brainstem sections were collected at 15, 21 and 31 days after EB injection and processed for GFAP immunohistochemical staining. Astrocytic reactivity was measured in a computerized system for image analysis. In Cur-treated rats, the GFAP-stained area around the lesion was significantly smaller in all periods after EB injection compared to untreated animals, showing that Cur reduces glial scar development following injury.

  2. Direct projections from hypothalamic orexin neurons to brainstem cardiac vagal neurons.

    Science.gov (United States)

    Dergacheva, Olga; Yamanaka, Akihiro; Schwartz, Alan R; Polotsky, Vsevolod Y; Mendelowitz, David

    2016-12-17

    Orexin neurons are known to augment the sympathetic control of cardiovascular function, however the role of orexin neurons in parasympathetic cardiac regulation remains unclear. To test the hypothesis that orexin neurons contribute to parasympathetic control we selectively expressed channelrhodopsin-2 (ChR2) in orexin neurons in orexin-Cre transgenic rats and examined postsynaptic currents in cardiac vagal neurons (CVNs) in the dorsal motor nucleus of the vagus (DMV). Simultaneous photostimulation and recording in ChR2-expressing orexin neurons in the lateral hypothalamus resulted in reliable action potential firing as well as large whole-cell currents suggesting a strong expression of ChR2 and reliable optogenetic excitation. Photostimulation of ChR2-expressing fibers in the DMV elicited short-latency (ranging from 3.2ms to 8.5ms) postsynaptic currents in 16 out of 44 CVNs tested. These responses were heterogeneous and included excitatory glutamatergic (63%) and inhibitory GABAergic (37%) postsynaptic currents. The results from this study suggest different sub-population of orexin neurons may exert diverse influences on brainstem CVNs and therefore may play distinct functional roles in parasympathetic control of the heart. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Diffusion tensor imaging of the inferior colliculus and brainstem auditory-evoked potentials in preterm infants

    Energy Technology Data Exchange (ETDEWEB)

    Reiman, Milla; Lehtonen, Liisa; Lapinleimu, Helena [Turku University Central Hospital, Department of Paediatrics, Turku (Finland); Parkkola, Riitta [Turku University Central Hospital, Department of Radiology and Turku PET Centre, Turku (Finland); Johansson, Reijo [Turku University Central Hospital, Department of Otorhinolaryngology, Turku (Finland); Jaeaeskelaeinen, Satu K. [Turku University Central Hospital, Department of Clinical Neurophysiology, Turku (Finland); Kujari, Harry [Turku University Central Hospital, Department of Pathology, Turku (Finland); Haataja, Leena [Turku University Central Hospital, Department of Paediatric Neurology, Turku (Finland)

    2009-08-15

    Preterm and low-birth-weight infants have an increased risk of sensorineural hearing loss. Brainstem auditory-evoked potentials (BAEP) are an effective method to detect subtle deficits in impulse conduction in the auditory pathway. Abnormalities on diffusion tensor imaging (DTI) have been shown to be associated with perinatal white-matter injury and reduced fractional anisotropy (FA) has been reported in patients with sensorineural hearing loss. To evaluate the possibility of a correlation between BAEP and DTI of the inferior colliculus in preterm infants. DTI at term age and BAEP measurements were performed on all very-low-birth-weight or very preterm study infants (n=56). FA and apparent diffusion coefficient (ADC) of the inferior colliculus were measured from the DTI. Shorter BAEP wave I, III, and V latencies and I-III and I-V intervals and higher wave V amplitude correlated with higher FA of the inferior colliculus. The association between the DTI findings of the inferior colliculus and BAEP responses suggests that DTI can be used to assess the integrity of the auditory pathway in preterm infants. (orig.)

  4. Abréviations

    OpenAIRE

    2014-01-01

    ADFM Association démocratique des femmes du Maroc AEMNA Association des étudiants musulmans nord-africains AKP Parti de la justice et du développement (Turquie) AMDH Association marocaine des droits de l’homme DGSN Direction générale de la sûreté nationale FAR Forces armées royales FDIC Front pour la défense des institutions constitutionnelles IER Instance équité et réconciliation INDH Initiative nationale pour le développement humain Jamâ’a Jamâ’at al-‘Adl wa al-Ihsân (Communauté pour la jus...

  5. Abréviations

    OpenAIRE

    2014-01-01

    A.D. Archives Départementales A.N. Archives Nationales Ars. Bibliothèque de l’Arsenal B.N. Bibliothèque Nationale Champ. Collection de Champagne 500 Col. Collection des Cinq cents de Colbert C. Collection Chérin CBH. Cabinet d’Hozier Clair. Collection Clairambault CRH. Carrés d’Hozier DB. Dossiers Bleus Dup. Collection Dupuy Fr. Collection des Manuscrits Français Mel Col. Collection des Mélanges de Colbert Ms. Manuscrit N.A.F. Collection des Nouveaux Manuscrits Français PO. Pièces Originales ...

  6. Annotation - Does Alzheimer's disease begin in the brainstem?

    Science.gov (United States)

    Simic, Goran; Stanić, Gabrijela; Mladinov, Mihovil; Jovanov-Milosevic, Natasa; Kostovic, Ivica; Hof, Patrick R.

    2009-01-01

    Although substantial evidence indicates that the progression of pathological changes of the neuronal cytoskeleton is crucial in determining the severity of dementia in Alzheimer's disease (AD), the exact causes and evolution of these changes, the initial site at which they begin, and the neuronal susceptibility levels for their development are poorly understood. The current clinical criteria for diagnosis of AD are focused mostly on cognitive deficits produced by dysfunction of hippocampal and high-order neocortical areas, whereas non-cognitive, behavioural, and psychological symptoms of dementia such as disturbances in mood, emotion, appetite, and wake-sleep cycle, confusion, agitation, and depression, have been less considered. The early occurrence of these symptoms suggests brainstem involvement, and more specifically of the serotonergic nuclei. In spite of the fact that the Braak staging system and NIA-RI criteria do not include their evaluation, several recent reports drew attention to the possibility of selective and early involvement of raphe nuclei, particularly the dorsal raphe nucleus (DRN), in the pathogenesis of AD. Based on these findings of differential susceptibility and anatomical connectivity, a novel pathogenetic scheme of AD progression was proposed. Although the precise mechanisms of neurofibrillary degeneration still await elucidation, we speculated that cumulative oxidative damage may be the main cause of DRN alterations, as the age is the main risk factor for sporadic AD. Within such a framework, β–amyloid production is considered only as one of the factors (although a significant one in familial cases) that promotes molecular series of events underlying AD-related neuropathological changes. PMID:19682326

  7. Brainstem auditory-evoked potential in Boxer dogs

    Directory of Open Access Journals (Sweden)

    Mariana Isa Poci Palumbo

    2014-10-01

    Full Text Available Brainstem auditory-evoked potential (BAEP has been widely used for different purposes in veterinary practice and is commonly used to identify inherited deafness and presbycusis. In this study, 43 Boxer dogs were evaluated using the BAEP. Deafness was diagnosed in 3 dogs (2 bilateral and 1 unilateral allowing the remaining 40 Boxers to be included for normative data analysis including an evaluation on the influence of age on the BAEP. The animals were divided into 2 groups of 20 Boxers each based on age. The mean age was 4.54 years (range, 1-8 in group I, and 9.83 years (range, 8.5-12 in group II. The mean latency for I, III, and V waves were 1.14 (±0.07, 2.64 (±0.11, and 3.48 (±0.10 ms in group I, and 1.20 (±0.12, 2.73 (±0.15, and 3.58 (±0.22 ms in group II, respectively. The mean inter-peak latencies for the I-III, III-V and I-V intervals were 1.50 (±0.15, 0.84 (±0.15, and 2.34 (±0.11 ms in group I, and 1.53 (±0.16, 0.85 (±0.15, and 2.38 (±0.19 ms in group II, respectively. Latencies of waves I and III were significant different between group I and II. For the I-III, III-V and I-V intervals, no significant differences were observed between the 2 groups. As far as we know, this is the first normative study of BAEP obtained from Boxer dogs.

  8. Objective detection and localization of multiple sclerosis lesions on magnetic resonance brainstem images: validation with auditory evoked potentials.

    Science.gov (United States)

    Stufflebeam, S M; Levine, R A; Gardner, J C; Fullerton, B C; Furst, M; Rosen, B R

    2000-01-01

    To develop an objective method for detecting multiple sclerosis (MS) brainstem lesions, magnetic resonance (MR) images (multiple planar, spin-echo, acquired in three planes of section) of sixteen MS patients and fourteen normal subjects were analyzed with an algorithm that detected regions with a relatively increased intensity on both a spin-echo image and a T2 image. To be considered a lesion, such regions had to overlap in at least two orthogonal planes. Using a digitized atlas of the human brainstem, the lesion locations were mapped with respect to the brainstem anatomy. This method was evaluated by comparing the location of MS lesions with the brainstem auditory evoked potentials obtained from these subjects. Brainstem lesions were detected in five MS patients; four had lesions impinging upon the auditory system and one did not. All four had abnormal evoked potentials. The fourteen normal subjects, the one MS patient with brainstem lesions outside the auditory pathway, and the eleven other MS patients with no brainstem lesions all had normal evoked potentials. The requirement that lesions be detected in at least two planes of section greatly improved the specificity of the algorithm. The consistency between the MR and brainstem auditory evoked potentials results supports the validity of this imaging analysis algorithm for objectively localizing brainstem lesions.

  9. ¡Abre los ojos! Un proyecto de mejora educativa para la prevención de drogas en adolescentes

    Directory of Open Access Journals (Sweden)

    Cecilia Mª AZORÍN ABELLÁN

    2016-01-01

    Full Text Available La Educación para la Salud (EpS es un tema transversal del currículo que adolece de propuestas didácticas novedosas para la intervención pedagógica. El objetivo del trabajo que se presenta es poner en marcha un plan de mejora para la prevención de drogadicciones en adolescentes. Para ello, se ha trabajado con un total de 142 estudiantes de 3º de Educación Secundaria Obligatoria (ESO con edades comprendidas entre los 14 y los 16 años que cursan estudios en el Instituto “Francisco Salzillo” de la localidad de Alcantarilla (Murcia. Concretamente, este artículo da luz al Proyecto ¡Abre los ojos!, que forma parte del Plan de Acción Tutorial (PAT y del Plan de Mejora para la Prevención de Drogas (PMPD propuesto desde el Departamento de Orientación. Se exponen ad hoc las actividades implementadas durante las 3 sesiones trabajadas con cada uno de los 6 grupos-clase escolarizados en este nivel. Haciendo uso de la reflexión-acción, el alumnado ha desarrollado una conciencia crítica acerca de los riesgos que entraña para la salud el consumo de drogas. Asimismo, mediante la técnica de grupos de discusión los discentes han realizado un interesante debate cuyas ideas han sido organizadas en torno a tres aspectos clave: causas por las que se empieza a consumir, cómo evitar caer en las drogas, y alternativas de ocio y tiempo libre para una vida saludable. Finalmente, se especifica la necesidad de abordar tareas de prevención en los centros educativos así como de facilitar información y de resolver las inquietudes de los jóvenes acerca de esta temática.

  10. Evidence for altered basal ganglia-brainstem connections in cervical dystonia.

    Directory of Open Access Journals (Sweden)

    Anne J Blood

    Full Text Available There has been increasing interest in the interaction of the basal ganglia with the cerebellum and the brainstem in motor control and movement disorders. In addition, it has been suggested that these subcortical connections with the basal ganglia may help to coordinate a network of regions involved in mediating posture and stabilization. While studies in animal models support a role for this circuitry in the pathophysiology of the movement disorder dystonia, thus far, there is only indirect evidence for this in humans with dystonia.In the current study we investigated probabilistic diffusion tractography in DYT1-negative patients with cervical dystonia and matched healthy control subjects, with the goal of showing that patients exhibit altered microstructure in the connectivity between the pallidum and brainstem. The brainstem regions investigated included nuclei that are known to exhibit strong connections with the cerebellum. We observed large clusters of tractography differences in patients relative to healthy controls, between the pallidum and the brainstem. Tractography was decreased in the left hemisphere and increased in the right hemisphere in patients, suggesting a potential basis for the left/right white matter asymmetry we previously observed in focal dystonia patients.These findings support the hypothesis that connections between the basal ganglia and brainstem play a role in the pathophysiology of dystonia.

  11. Abnormal trajectories in cerebellum and brainstem volumes in carriers of the fragile X premutation.

    Science.gov (United States)

    Wang, Jun Yi; Hessl, David; Hagerman, Randi J; Simon, Tony J; Tassone, Flora; Ferrer, Emilio; Rivera, Susan M

    2017-07-01

    Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder typically affecting male premutation carriers with 55-200 CGG trinucleotide repeat expansions in the FMR1 gene after age 50. The aim of this study was to examine whether cerebellar and brainstem changes emerge during development or aging in late life. We retrospectively analyzed magnetic resonance imaging scans from 322 males (age 8-81 years). Volume changes in the cerebellum and brainstem were contrasted with those in the ventricles and whole brain. Compared to the controls, premutation carriers without FXTAS showed significantly accelerated volume decrease in the cerebellum and whole brain, flatter inverted U-shaped trajectory of the brainstem, and larger ventricles. Compared to both older controls and premutation carriers without FXTAS, carriers with FXTAS exhibited significant volume decrease in the cerebellum and whole brain and accelerated volume decrease in the brainstem. We therefore conclude that cerebellar and brainstem volumes were likely affected during both development and progression of neurodegeneration in premutation carriers, suggesting that interventions may need to start early in adulthood to be most effective. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Correlation of Acute and Late Brainstem Toxicities With Dose-Volume Data for Pediatric Patients With Posterior Fossa Malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Nanda, Ronica H., E-mail: rhazari@emory.edu [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States); Ganju, Rohit G.; Schreibmann, Edward [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States); Chen, Zhengjia; Zhang, Chao [Department of Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Emory University Rollins School of Public Health, Atlanta, Georgia (United States); Jegadeesh, Naresh; Cassidy, Richard; Deng, Claudia; Eaton, Bree R.; Esiashvili, Natia [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States)

    2017-06-01

    Purpose: Radiation-induced brainstem toxicity after treatment of pediatric posterior fossa malignancies is incompletely understood, especially in the era of intensity modulated radiation therapy (IMRT). The rates of, and predictive factors for, brainstem toxicity after photon RT for posterior fossa tumors were examined. Methods and Materials: After institutional review board approval, 60 pediatric patients treated at our institution for nonmetastatic infratentorial ependymoma and medulloblastoma with IMRT were included in the present analysis. Dosimetric variables, including the mean and maximum dose to the brainstem, the dose to 10% to 90% of the brainstem (in 10% increments), and the volume of the brainstem receiving 40, 45, 50, and 55 Gy were recorded for each patient. Acute (onset within 3 months) and late (>3 months of RT completion) RT-induced brainstem toxicities with clinical and radiographic correlates were scored using Common Terminology Criteria for Adverse Events, version 4.0. Results: Patients aged 1.4 to 21.8 years underwent IMRT or volumetric arc therapy postoperatively to the posterior fossa or tumor bed. At a median clinical follow-up period of 2.8 years, 14 patients had developed symptomatic brainstem toxicity (crude incidence 23.3%). No correlation was found between the dosimetric variables examined and brainstem toxicity. Vascular injury or ischemia showed a strong trend toward predicting brainstem toxicity (P=.054). Patients with grade 3 to 5 brainstem toxicity had undergone treatment to significant volumes of the posterior fossa. Conclusion: The results of the present series demonstrate a low, but not negligible, risk of brainstem radiation necrosis for pediatric patients with posterior fossa malignancies treated with IMRT. No specific dose-volume correlations were identified; however, modern treatment volumes might help limit the incidence of severe toxicity. Additional work investigating inherent biologic sensitivity might also provide

  13. Congenital Trismus From Brainstem Dysgenesis: Case Report and Review of Literature.

    Science.gov (United States)

    Hong, Chris J; Caulley, Lisa; Kohlert, Scott; Graham, Gail E; McMillan, Hugh J; Michaud, Jean; Vaccani, Jean-Philippe

    2016-07-01

    Trismus refers to any condition inducing limited mouth opening and may present as a result of acquired or congenital pathology. We present the case of a newborn who presented with severe, congenital trismus due to brainstem dysgenesis. We describe the course of his investigations, and a multidisciplinary approach to the management of his care and follow-up. To our knowledge, this is one of the earliest reported cases of congenital trismus attributable to brainstem dysgenesis. A literature review was conducted to provide an overview of the differential pathogenesis as it presents in congenital cases and discuss the complexity of managing congenital trismus due to brainstem dysgenesis in a neonate and infant. Copyright © 2016 by the American Academy of Pediatrics.

  14. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura

    DEFF Research Database (Denmark)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E

    2017-01-01

    symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering...... of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas......-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability...

  15. Improved Transient Response Estimations in Predicting 40 Hz Auditory Steady-State Response Using Deconvolution Methods

    Directory of Open Access Journals (Sweden)

    Xiaodan Tan

    2017-12-01

    Full Text Available The auditory steady-state response (ASSR is one of the main approaches in clinic for health screening and frequency-specific hearing assessment. However, its generation mechanism is still of much controversy. In the present study, the linear superposition hypothesis for the generation of ASSRs was investigated by comparing the relationships between the classical 40 Hz ASSR and three synthetic ASSRs obtained from three different templates for transient auditory evoked potential (AEP. These three AEPs are the traditional AEP at 5 Hz and two 40 Hz AEPs derived from two deconvolution algorithms using stimulus sequences, i.e., continuous loop averaging deconvolution (CLAD and multi-rate steady-state average deconvolution (MSAD. CLAD requires irregular inter-stimulus intervals (ISIs in the sequence while MSAD uses the same ISIs but evenly-spaced stimulus sequences which mimics the classical 40 Hz ASSR. It has been reported that these reconstructed templates show similar patterns but significant difference in morphology and distinct frequency characteristics in synthetic ASSRs. The prediction accuracies of ASSR using these templates show significant differences (p < 0.05 in 45.95, 36.28, and 10.84% of total time points within four cycles of ASSR for the traditional, CLAD, and MSAD templates, respectively, as compared with the classical 40 Hz ASSR, and the ASSR synthesized from the MSAD transient AEP suggests the best similarity. And such a similarity is also demonstrated at individuals only in MSAD showing no statistically significant difference (Hotelling's T2 test, T2 = 6.96, F = 0.80, p = 0.592 as compared with the classical 40 Hz ASSR. The present results indicate that both stimulation rate and sequencing factor (ISI variation affect transient AEP reconstructions from steady-state stimulation protocols. Furthermore, both auditory brainstem response (ABR and middle latency response (MLR are observed in contributing to the composition of ASSR but

  16. Delayed Brainstem Hemorrhage Secondary to Mild Traumatic Head Injury: Report of Case with Good Recovery.

    Science.gov (United States)

    Hou, Kun; Zhao, Jinchuan; Gao, Xianfeng; Zhu, Xiaobo; Li, Guichen

    2017-09-01

    In clinical practice, secondary traumatic brainstem hemorrhage often develops during descending transtentorial herniation due to raised intracranial pressure, which is known as Duret hemorrhage. Although usually considered a fatal and irreversible event, in rare circumstances, victims of Duret hemorrhage could gain favorable outcomes. To our knowledge, secondary brainstem hemorrhage due to mild traumatic head injury without descending transtentorial herniation has never been reported. In this report, we present a case of delayed brainstem hemorrhage secondary to a relatively mild traumatic brain injury that experienced a rapid and favorable recovery. A 48-year-old man was admitted for a motorcycle accident. Head computed tomography 2 hours after the accident revealed mild subarachnoid hemorrhage at the interpeduncular cistern. In the following in-hospital days, he experienced 2 episodes of mental state deterioration and increase of the SAH and hematoma extension to the brainstem. A digital subtraction angiography was performed with no positive finding of vascular anomaly and evident cerebral vasospasm. He experienced a rapid and favorable recovery. His Glasgow Outcome Scale score was 5 at 3 months' follow-up. We present a rare case of secondary traumatic brainstem hemorrhage that experienced a rapid and good recovery process. The mechanism is still obscure to us and needs to be further studied. Although traumatic brainstem hemorrhage usually means a fatal event to most of the patients, some patients may experience a favorable recovery. This rare circumstance should be stressed in prognosis consultation and clinical management of these kinds of patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Evidence for brainstem network disruption in temporal lobe epilepsy and sudden unexplained death in epilepsy

    Directory of Open Access Journals (Sweden)

    Susanne G. Mueller

    2014-01-01

    Full Text Available The symptoms witnessed in unexplained death in epilepsy (SUDEP suggest a breakdown of central autonomic control. Since the brainstem plays a crucial role in autonomic control, the objectives of this study were 1. To investigate if temporal lobe epilepsy (TLE is associated with brainstem atrophy and to characterize it using graph Analysis 2. To compare the findings with those in two probable TLESUDEP. T1 images were obtained from 17 controls, 30 TLE (16 with mesial-temporal-sclerosis (TLE-MTS and 14 without (TLE-no and from 2 patients who died of SUDEP. The brainstem was extracted, warped onto a brainstem atlas and Jacobian determinants maps (JDM calculated. SPM8 was used to compare the JDMs at the group level, z-score maps were calculated for single subject analysis. Brainstem regions encompassing autonomic structures were identified based on macroscopic landmarks and mean z-scores from 5 × 5 × 5 voxel cubes extracted to calculate a new measure called atrophy-similarity index (ASI for graph analysis. TLE-MTS had volume loss in the dorsal mesencephalon. The SUDEP cases had severe and more extensive volume loss in the same region. Nodal degrees and participation coefficients were decreased and local efficiency increased in SUDEP compared to controls. TLE is associated with volume loss in brainstem regions involved in autonomic control. Structural damage in these regions might increase the risk for a fatal dysregulation during situations with increased demand such as following severe seizures.

  18. [Forensic application of brainstem auditory evoked potential in patients with brain concussion].

    Science.gov (United States)

    Zheng, Xing-Bin; Li, Sheng-Yan; Huang, Si-Xing; Ma, Ke-Xin

    2008-12-01

    To investigate changes of brainstem auditory evoked potential (BAEP) in patients with brain concussion. Nineteen patients with brain concussion were studied with BAEP examination. The data was compared to the healthy persons reported in literatures. The abnormal rate of BAEP for patients with brain concussion was 89.5%. There was a statistically significant difference between the abnormal rate of patients and that of healthy persons (Pconcussion was 73.7%, indicating dysfunction of the brainstem in those patients. BAEP might be helpful in forensic diagnosis of brain concussion.

  19. Brainstem and Autonomic Nervous System Dysfunction: A Neurosurgical Point of View.

    Science.gov (United States)

    Martín-Gallego, A; González-García, L; Carrasco-Brenes, A; Segura-Fernández-Nogueras, M; Delgado-Babiano, A; Ros-Sanjuán, A; Romero-Moreno, L; Domínguez-Páez, M; Dawid-Milner, M S; Arráez-Sánchez, M A

    2017-01-01

    Central autonomic control nuclei and pathways are mainly integrated within the brainstem, especially in the medulla oblongata. Lesions within these structures can lead to central dysautonomia.Central autonomic control structures can be damaged by tumors, during surgery, or by other neurosurgical pathologies. These may elicit clinical or subclinical autonomic complications that can constitute a serious clinical problem.The authors present a broad review of the central autonomic nervous system, its possible dysfunctions, and the relation between neurosurgery and this "not-well-known system". Preliminary results of an autonomic study of brainstem lesions that is currently being carried out by the authors are also shown.

  20. Increased astrocytic expression of metallothioneins I + II in brainstem of adult rats treated with 6-aminonicotinamide

    DEFF Research Database (Denmark)

    Penkowa, Milena; Hidalgo, Juan; Moos, Torben

    1997-01-01

    The cerebral distribution of metallothioneins I and II (MT-I + II) was studied in adult rats subjected to i.p. injection with the gliotoxin 6-aminonicotinamide (6-AN). Grey matter regions of the brainstem heralded numerous OX-42-positive macrophages and microglia, indicating that 6-AN primarily...... were observed. The blood-brain barrier (BBB) to serum albumin was compromised in the entire brainstem. The astrocytic expression of MT-I + II could reflect the brains needs to scavenge metal ions released from either damaged cells or plasma proteins entering the brain due to the injured BBB, as well...

  1. Brainstem serotonergic deficiency in sudden infant death syndrome.

    Science.gov (United States)

    Duncan, Jhodie R; Paterson, David S; Hoffman, Jill M; Mokler, David J; Borenstein, Natalia S; Belliveau, Richard A; Krous, Henry F; Haas, Elisabeth A; Stanley, Christina; Nattie, Eugene E; Trachtenberg, Felicia L; Kinney, Hannah C

    2010-02-03

    Sudden infant death syndrome (SIDS) is postulated to result from abnormalities in brainstem control of autonomic function and breathing during a critical developmental period. Abnormalities of serotonin (5-hydroxytryptamine [5-HT]) receptor binding in regions of the medulla oblongata involved in this control have been reported in infants dying from SIDS. To test the hypothesis that 5-HT receptor abnormalities in infants dying from SIDS are associated with decreased tissue levels of 5-HT, its key biosynthetic enzyme (tryptophan hydroxylase [TPH2]), or both. Autopsy study conducted to analyze levels of 5-HT and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA); levels of TPH2; and 5-HT(1A) receptor binding. The data set was accrued between 2004 and 2008 and consisted of 41 infants dying from SIDS (cases), 7 infants with acute death from known causes (controls), and 5 hospitalized infants with chronic hypoxia-ischemia. Serotonin and metabolite tissue levels in the raphé obscurus and paragigantocellularis lateralis (PGCL); TPH2 levels in the raphé obscurus; and 5-HT(1A) binding density in 5 medullary nuclei that contain 5-HT neurons and 5 medullary nuclei that receive 5-HT projections. Serotonin levels were 26% lower in SIDS cases (n = 35) compared with age-adjusted controls (n = 5) in the raphé obscurus (55.4 [95% confidence interval {CI}, 47.2-63.6] vs 75.5 [95% CI, 54.2-96.8] pmol/mg protein, P = .05) and the PGCL (31.4 [95% CI, 23.7-39.0] vs 40.0 [95% CI, 20.1-60.0] pmol/mg protein, P = .04). There was no evidence of excessive 5-HT degradation assessed by 5-HIAA levels, 5-HIAA:5-HT ratio, or both. In the raphé obscurus, TPH2 levels were 22% lower in the SIDS cases (n = 34) compared with controls (n = 5) (151.2% of standard [95% CI, 137.5%-165.0%] vs 193.9% [95% CI, 158.6%-229.2%], P = .03). 5-HT(1A) receptor binding was 29% to 55% lower in 3 medullary nuclei that receive 5-HT projections. In 4 nuclei, 3 of which contain 5-HT neurons, there was a decrease with

  2. Enhanced decolorization of azo dye in a small pilot-scale anaerobic baffled reactor coupled with biocatalyzed electrolysis system (ABR-BES): a design suitable for scaling-up.

    Science.gov (United States)

    Cui, Dan; Guo, Yu-Qi; Lee, Hyung-Sool; Wu, Wei-Min; Liang, Bin; Wang, Ai-Jie; Cheng, Hao-Yi

    2014-07-01

    A four-compartment anaerobic baffled reactor (ABR) incorporated with membrane-less biocatalyzed electrolysis system (BES) was tested for the treatment of azo dye (alizarin yellow R, AYR) wastewater (AYR, 200 mg L(-1); glucose, 1000 mg L(-1)). The ABR-BES was operated without and with external power supply to examine AYR reduction process and reductive intermediates with different external voltages (0.3, 0.5 and 0.7 V) and hydraulic retention times (HRT: 8, 6 and 4h). The decolorization efficiency in the ABR-BES (8h HRT, 0.5 V) was higher than that in ABR-BES without electrolysis, i.e. 95.1 ± 1.5% versus 86.9 ± 6.3%. Incorporation of BES with ABR accelerated the consumption of VFAs (mainly acetate) and attenuated biogas (methane) production. Higher power supply (0.7 V) enhanced AYR decolorization efficiency (96.4 ± 1.8%), VFAs removal, and current density (24.1 Am(-3) TCV). Shorter HRT increased volumetric AYR decolorization rates, but decreased AYR decolorization efficiency. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Physical-chemical and operational performance of an anaerobic baffled reactor (ABR treating swine wastewater - 10.4025/actascitechnol.v32i4.7203

    Directory of Open Access Journals (Sweden)

    Erlon Lopes Pereira

    2010-12-01

    Full Text Available Since hog raising concentrates a huge amount of swine manure in small areas, it is considered by the environmental government organizations to be one of the most potentially pollutant activities. Therefore the main objective of this research was to evaluate by operational criteria and removal efficiency, the performance of a Anaerobic Baffled Reactor (ABR, working as a biological pre-treatment of swine culture effluents. The physical-chemical analyses carried out were: total COD, BOD5, total solids (TS, fix (TFS and volatiles (TVS, temperature, pH, total Kjeldahl nitrogen, phosphorus, total acidity and alkalinity. The ABR unit worked with an average efficiency of 65.2 and 76.2%, respectively, concerning total COD and BOD5, with a hydraulic retention time (HRT about 15 hours. The results for volumetric organic loading rate (VOLR, organic loading rate (OLR and hydraulic loading rate (HLR were: 4.46 kg BOD m-3 day-1; 1.81 kg BOD5 kg TVS-1 day-1 and 1.57 m3 m-3 day-1, respectively. The average efficiency of the whole treatment system for total COD and BOD5 removal were 66.5 and 77.8%, showing an adequate performance in removing the organic matter from swine wastewater.

  4. CD8+ T Cells Induce Fatal Brainstem Pathology during Cerebral Malaria via Luminal Antigen-Specific Engagement of Brain Vasculature.

    Directory of Open Access Journals (Sweden)

    Phillip A Swanson

    2016-12-01

    Full Text Available Cerebral malaria (CM is a severe complication of Plasmodium falciparum infection that results in thousands of deaths each year, mostly in African children. The in vivo mechanisms underlying this fatal condition are not entirely understood. Using the animal model of experimental cerebral malaria (ECM, we sought mechanistic insights into the pathogenesis of CM. Fatal disease was associated with alterations in tight junction proteins, vascular breakdown in the meninges / parenchyma, edema, and ultimately neuronal cell death in the brainstem, which is consistent with cerebral herniation as a cause of death. At the peak of ECM, we revealed using intravital two-photon microscopy that myelomonocytic cells and parasite-specific CD8+ T cells associated primarily with the luminal surface of CNS blood vessels. Myelomonocytic cells participated in the removal of parasitized red blood cells (pRBCs from cerebral blood vessels, but were not required for the disease. Interestingly, the majority of disease-inducing parasite-specific CD8+ T cells interacted with the lumen of brain vascular endothelial cells (ECs, where they were observed surveying, dividing, and arresting in a cognate peptide-MHC I dependent manner. These activities were critically dependent on IFN-γ, which was responsible for activating cerebrovascular ECs to upregulate adhesion and antigen-presenting molecules. Importantly, parasite-specific CD8+ T cell interactions with cerebral vessels were impaired in chimeric mice rendered unable to present EC antigens on MHC I, and these mice were in turn resistant to fatal brainstem pathology. Moreover, anti-adhesion molecule (LFA-1 / VLA-4 therapy prevented fatal disease by rapidly displacing luminal CD8+ T cells from cerebrovascular ECs without affecting extravascular T cells. These in vivo data demonstrate that parasite-specific CD8+ T cell-induced fatal vascular breakdown and subsequent neuronal death during ECM is associated with luminal, antigen

  5. CD8+ T Cells Induce Fatal Brainstem Pathology during Cerebral Malaria via Luminal Antigen-Specific Engagement of Brain Vasculature

    Science.gov (United States)

    Swanson, Phillip A.; Hart, Geoffrey T.; Russo, Matthew V.; Nayak, Debasis; Yazew, Takele; Peña, Mirna; Khan, Shahid M.; Pierce, Susan K.; McGavern, Dorian B.

    2016-01-01

    Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection that results in thousands of deaths each year, mostly in African children. The in vivo mechanisms underlying this fatal condition are not entirely understood. Using the animal model of experimental cerebral malaria (ECM), we sought mechanistic insights into the pathogenesis of CM. Fatal disease was associated with alterations in tight junction proteins, vascular breakdown in the meninges / parenchyma, edema, and ultimately neuronal cell death in the brainstem, which is consistent with cerebral herniation as a cause of death. At the peak of ECM, we revealed using intravital two-photon microscopy that myelomonocytic cells and parasite-specific CD8+ T cells associated primarily with the luminal surface of CNS blood vessels. Myelomonocytic cells participated in the removal of parasitized red blood cells (pRBCs) from cerebral blood vessels, but were not required for the disease. Interestingly, the majority of disease-inducing parasite-specific CD8+ T cells interacted with the lumen of brain vascular endothelial cells (ECs), where they were observed surveying, dividing, and arresting in a cognate peptide-MHC I dependent manner. These activities were critically dependent on IFN-γ, which was responsible for activating cerebrovascular ECs to upregulate adhesion and antigen-presenting molecules. Importantly, parasite-specific CD8+ T cell interactions with cerebral vessels were impaired in chimeric mice rendered unable to present EC antigens on MHC I, and these mice were in turn resistant to fatal brainstem pathology. Moreover, anti-adhesion molecule (LFA-1 / VLA-4) therapy prevented fatal disease by rapidly displacing luminal CD8+ T cells from cerebrovascular ECs without affecting extravascular T cells. These in vivo data demonstrate that parasite-specific CD8+ T cell-induced fatal vascular breakdown and subsequent neuronal death during ECM is associated with luminal, antigen

  6. Altered GABAA receptor expression in brainstem nuclei and SUDEP in Gabrg2(+/Q390X) mice associated with epileptic encephalopathy.

    Science.gov (United States)

    Xia, Geqing; P Pourali, Sarah; Warner, Timothy A; Zhang, Chun-Qing; L Macdonald, Robert; Kang, Jing-Qiong

    2016-07-01

    Sudden unexpected death in epilepsy (SUDEP) is the leading cause for death in individuals with epilepsy. The frequency of SUDEP correlates with the severity of epilepsies and lack of response to antiepileptic drug treatment, but the underlying mechanisms of SUDEP have not been elucidated fully. GABRG2(Q390X) is a mutation associated with the epileptic encephalopathy Dravet syndrome (DS) and with genetic epilepsy with febrile seizures plus (GEFS+) in patients. The Gabrg2(+/Q390X) knockin (KI) mouse phenocopies the major features of DS and GEFS+ and has SUDEP throughout life. The Gabrg2(+/-) knockout (KO) mouse is associated with infrequent absence seizures and represents a model of mild absence epilepsy syndrome without increased mortality. To explore the basis for SUDEP in DS and GEFS+, we compared mutant γ2 subunit and wild-type α1 and β2/3 subunit expression in mice in brainstem nuclei associated with respiratory function including the solitary tract, pre-Botzinger complex and Kolliker-Fuse nuclei. We found that synaptic GABAA receptors were reduced while intracellular nonfunctional γ2(Q390X) subunits were increased in the heterozygous DS and GEFS+ KI mice, but not in the heterozygous absence epilepsy KO mice. Given the critical role of these nuclei in cardiorespiratory function, it is likely the impaired GABAergic transmission and neuronal dysfunction in these brainstem nuclei are involved in the cardiorespiratory collapse in SUDEP. The study provides novel mechanistic insights into cardiorespiratory failure of SUDEP. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Ventilation induced apnea and its effect on dorsal brainstem inspiratory neurones in the rat

    NARCIS (Netherlands)

    Subramanian, Hari H.; Balnave, Ron J.; Chow, Chin M.

    2007-01-01

    The purpose of this study was to examine the effect of mechanical ventilation (MV) on inherent breathing and on dorsal brainstem nucleus tractus solitarius (NTS) respiratory cell function. In pentobarbitone-anaesthetised rats, application of MV at combined high frequencies and volumes (representing

  8. Convection enhanced delivery of carmustine to the murine brainstem: a feasibility study

    NARCIS (Netherlands)

    Sewing, A. Charlotte P.; Caretti, Viola; Lagerweij, Tonny; Schellen, Pepijn; Jansen, Marc H. A.; van Vuurden, Dannis G.; Idema, Sander; Molthoff, Carla F. M.; Vandertop, W. Peter; Kaspers, Gertjan J. L.; Noske, David P.; Hulleman, Esther

    2014-01-01

    Systemic delivery of therapeutic agents remains ineffective against diffuse intrinsic pontine glioma (DIPG), possibly due to an intact blood-brain-barrier (BBB) and to dose-limiting toxicity of systemic chemotherapeutic agents. Convection-enhanced delivery (CED) into the brainstem may provide an

  9. The human premotor oculomotor brainstem system - can it help to understand oculomotor symptoms in Huntington's disease?

    NARCIS (Netherlands)

    Rueb, U.; Heinsen, H.; Brunt, E. R.; Landwehrmeyer, B.; Den Dunnen, W. F. A.; Gierga, K.; Deller, T.

    Recent progress in oculomotor research has enabled new insights into the functional neuroanatomy of the human premotor oculomotor brainstem network. In the present review, we provide an overview of its functional neuroanatomy and summarize the broad range of oculomotor dysfunctions that may occur in

  10. Effects of brainstem lesions on the masseter inhibitory reflex. Functional mechanisms of reflex pathways

    NARCIS (Netherlands)

    Ongerboer de Visser, B. W.; Cruccu, G.; Manfredi, M.; Koelman, J. H.

    1990-01-01

    The masseter inhibitory reflex (MIR) was investigated in 16 patients with localized brainstem lesions involving the trigeminal system. The MIR consists of two phases of EMG silence (S1 and S2) evoked by stimulation of the mental nerve during maximal clenching of the teeth. The extent of the lesions

  11. Spreading depolarization in the brainstem mediates sudden cardiorespiratory arrest in mouse SUDEP models.

    Science.gov (United States)

    Aiba, Isamu; Noebels, Jeffrey L

    2015-04-08

    Cardiorespiratory collapse after a seizure is the leading cause of sudden unexpected death in epilepsy (SUDEP) in young persons, but why only certain individuals are at risk is unknown. To identify a mechanism for this lethal cardiorespiratory failure, we examined whether genes linked to increased SUDEP risk lower the threshold for spreading depolarization (SD), a self-propagating depolarizing wave that silences neuronal networks. Mice carrying mutations in Kv1.1 potassium channels (-/-) and Scn1a sodium ion channels (+/R1407X) phenocopy many aspects of human SUDEP. In mutant, but not wild-type mice, seizures initiated by topical application of 4-aminopyridine to the cortex led to a slow, negative DC potential shift recorded in the dorsal medulla, a brainstem region that controls cardiorespiratory pacemaking. This irreversible event slowly depolarized cells and inactivated synaptic activity, producing cardiorespiratory arrest. Local initiation of SD in this region by potassium chloride microinjection also elicited electroencephalographic suppression, apnea, bradycardia, and asystole, similar to the events seen in monitored human SUDEP. In vitro study of brainstem slices confirmed that mutant mice had a lower threshold for SD elicited by metabolic substrate depletion and that immature mice were at greater risk than adults. Deletion of the gene encoding tau, which prolongs life in these mutants, also restored the normal SD threshold in Kv1.1-mutant mouse brainstem. Thus, brainstem SD may be a critical threshold event linking seizures and SUDEP. Copyright © 2015, American Association for the Advancement of Science.

  12. The role of hypofractionation radiotherapy for diffuse intrinsic brainstem glioma in children: a pilot study.

    NARCIS (Netherlands)

    Janssens, G.O.; Gidding, C.E.M.; Lindert, E.J. van; Oldenburger, F.R.; Erasmus, C.E.; Schouten-Meeteren, A.Y.; Kaanders, J.H.A.M.

    2009-01-01

    PURPOSE: Most children with a diffuse intrinsic brainstem glioma will die within 1 year after diagnosis. To reduce patient burden, we investigated the feasibility of a radical hypofractionation radiotherapy schedule, given over 3 weeks, as an alternative to the standard regimen (30 fractions over 6

  13. The role of hypofractionation radiotherapy for diffuse intrinsic brainstem glioma in children: a pilot study

    NARCIS (Netherlands)

    Janssens, Geert O. R. J.; Gidding, Corrie E. M.; van Lindert, Erik J.; Oldenburger, Foppe R.; Erasmus, Corrie E.; Schouten-Meeteren, Antoinette Y. N.; Kaanders, Johannes H. A. M.

    2009-01-01

    Most children with a diffuse intrinsic brainstem glioma will die within 1 year after diagnosis. To reduce patient burden, we investigated the feasibility of a radical hypofractionation radiotherapy schedule, given over 3 weeks, as an alternative to the standard regimen (30 fractions over 6 weeks).

  14. Developmental study of vitamin C distribution in children's brainstems by immunohistochemistry.

    Science.gov (United States)

    Coveñas, R; González-Fuentes, J; Rivas-Infante, E; Lagartos-Donate, M J; Mangas, A; Geffard, M; Arroyo-Jiménez, M M; Cebada-Sánchez, S; Insausti, R; Marcos, P

    2015-09-01

    Vitamin C (Vit C) is an important antioxidant, exerts powerful neuroprotective brain effects and plays a role in neuronal development and maturation. Vit C is present in brain tissue at higher concentrations than in other organs, but its detailed distribution in brain is unknown. Immunohistochemical detection of this vitamin has been performed by using a highly specific antibody against Vit C. The aim of the present work was to analyze the distribution of Vit C in children's brainstems during postnatal development, comparing two groups of ages: younger and older than one year of life. In general, the same areas showing neurons with Vit C in young cases are also immunostained at older ages. The distribution of neurons containing Vit C was broader in the brainstems of older children, suggesting that brainstem neurons maintain or even increase their ability to retain Vit C along the life span. Immunohistochemical labeling revealed only cell bodies containing this vitamin, and no immunoreactive fibers were observed. The distribution pattern of Vit C in children's brainstems suggests a possible role of Vit C in brain homeostatic regulation. In addition, the constant presence of Vit C in neurons of locus coeruleus supports the important role of Vit C in noradrenaline synthesis, which seemed to be maintained along postnatal development. Copyright © 2015 Elsevier GmbH. All rights reserved.

  15. Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

    International Nuclear Information System (INIS)

    Kutomi, Kimiko

    2005-01-01

    Developmental abnormality of brainstem is shown in pediatric patients with mental retardation, autism, periventricular leukomalacia, neurodegenerative disease, and so on. Our purpose here is to clarify the normal developmental pattern of the brainstem. We measured the area of tectum, midbrain tegmentum, pons, basis pontis and pontine tegmentum on mid-sagittal MR images in 111 children (newborn to 20 year old). Different growth patterns were shown in all parts of the brainstem. Tectum showed a subtle increase in area from the newborn to adult period, while midbrain tegmentum and pontine tegmenturn showed a mild and gradual increase in area. Pons and pontine tegmentum showed a rapid and prominent increase in area from newborn to infant period and gradual increase in area until the adult period. These different growth patterns seemed to be consistent with differences in the myelination cycles of the neuronal fibers, maturation of the nuclei and proliferation of glial cells in each part of the brainstem. Mid-sagittal MR imaging of the head is accurate and reproducible and is used conveniently in routine head MR study, making it very useful for the diagnosis of many central nervous diseases and anomalies. We believe that this new milestone provided in this study will be helpful in distinguishing normal children from those that have neurodegenerative disorders. (author)

  16. Relationship between brainstem neurodegeneration and clinical impairment in traumatic spinal cord injury

    Directory of Open Access Journals (Sweden)

    Patrick Grabher

    2017-01-01

    Conclusion: Neurodegeneration, indicated by volume loss and myelin reductions, is evident in major brainstem pathways and nuclei following traumatic SCI; the magnitude of these changes relating to clinical impairment. Thus, quantitative MRI protocols offer new targets, which may be used as neuroimaging biomarkers in treatment trials.

  17. Urotensin II modulates rapid eye movement sleep through activation of brainstem cholinergic neurons

    DEFF Research Database (Denmark)

    Huitron-Resendiz, Salvador; Kristensen, Morten Pilgaard; Sánchez-Alavez, Manuel

    2005-01-01

    Urotensin II (UII) is a cyclic neuropeptide with strong vasoconstrictive activity in the peripheral vasculature. UII receptor mRNA is also expressed in the CNS, in particular in cholinergic neurons located in the mesopontine tegmental area, including the pedunculopontine tegmental (PPT) and later...... brainstem neurons....

  18. On the relation between self-reported cognitive fatigue and the posterior hypothalamic-brainstem network

    NARCIS (Netherlands)

    Hanken, K.; Manousi, A.; Klein, J.; Kastrup, A.; Eling, P.A.T.M.; Hildebrandt, H.

    2016-01-01

    Background and Purpose: Various causes have been suggested for multiple sclerosis (MS) related fatigue. Hypothalamus-brainstem fibres play a role in sleep−wake regulation and in hypothalamic deactivation during inflammatory states. Hence, they may play a role for experiencing fatigue by changing

  19. Vasopressin (VP) and neuropeptide FF (NPFF) systems in the normal and hypertensive human brainstem

    NARCIS (Netherlands)

    Goncharuk, Valeri D.; Buijs, Ruud M.; Jhamandas, Jack H.; Swaab, Dick F.

    2011-01-01

    Vasopressin (VP)-, neuropeptide FF (NPFF)-, and tyrosine hydroxylase (TH)-expressing neurons were studied by means of single and double immunocytochemistry in the human brainstem of controls who died suddenly due to trauma and of patients who suffered from essential hypertension and died due to

  20. High-Resolution MR Imaging of the Human Brainstem In vivo at 7 Tesla

    Science.gov (United States)

    Deistung, Andreas; Schäfer, Andreas; Schweser, Ferdinand; Biedermann, Uta; Güllmar, Daniel; Trampel, Robert; Turner, Robert; Reichenbach, Jürgen R.

    2013-01-01

    The human brainstem, which comprises a multitude of axonal nerve fibers and nuclei, plays an important functional role in the human brain. Depicting its anatomy non-invasively with high spatial resolution may thus in turn help to better relate normal and pathological anatomical variations to medical conditions as well as neurological and peripheral functions. We explored the potential of high-resolution magnetic resonance imaging (MRI) at 7 T for depicting the intricate anatomy of the human brainstem in vivo by acquiring and generating images with multiple contrasts: T2-weighted images, quantitative maps of longitudinal relaxation rate (R1 maps) and effective transverse relaxation rate (R2* maps), magnetic susceptibility maps, and direction-encoded track-density images. Images and quantitative maps were compared with histological stains and anatomical atlases to identify nerve nuclei and nerve fibers. Among the investigated contrasts, susceptibility maps displayed the largest number of brainstem structures. Contrary to R1 maps and T2-weighted images, which showed rather homogeneous contrast, R2* maps, magnetic susceptibility maps, and track-density images clearly displayed a multitude of smaller and larger fiber bundles. Several brainstem nuclei were identifiable in sections covering the pons and medulla oblongata, including the spinal trigeminal nucleus and the reticulotegmental nucleus on magnetic susceptibility maps as well as the inferior olive on R1, R2*, and susceptibility maps. The substantia nigra and red nuclei were visible in all contrasts. In conclusion, high-resolution, multi-contrast MR imaging at 7 T is a versatile tool to non-invasively assess the individual anatomy and tissue composition of the human brainstem. PMID:24194710

  1. Four cases with localized brain-stem lesion on CT scan following closed head injury

    International Nuclear Information System (INIS)

    Saeki, Naokatsu; Odaki, Masaru; Oka, Nobuo; Takase, Manabu; Ono, Junichi.

    1981-01-01

    Cases of primary brain-stem injury following closed head injury, verified by a CT scan, have been increasingly reported. However, most of them have other intracranial lesions in addition to the brain stem, resulting in a poor outcome. The CT scan of 200 cases with severe head injury-Araki's classification of types 3 and 4 - were analysed. Four cases out of them had localized brain-stem lesion without any other significant intracranial injury on a CT scan at the acute stage and had a better outcome than had previously been reported. In this analysis, these 4 cases were studied, and the CT findings, prognosis, and pathogenesis of the localized brain-stem injury were discussed. Follow-up CT of three cases, and taken one month or more later, showed diffuse cortical atrophy. This may indicate the presence of diffuse cerebral injury which could not be seen on CT scans at the acute stage. This atrophic change may also be related with the mechanism of posttraumatic conscious impairment and posttraumatic neurological deficits, such as mental symptoms and impairment of the higher cortical function. Shearing injury is a probable pathogenesis for this diffuse cortical injury. On the other hand, one case did not have any cortical atrophy on a follow-up CT scan. Therefore, this is a case with a localized primary brain-stem injury. Coup injury against the brain stem by a tentorial margin in a case with a small tentorial opening is a possible mechanism producing the localized brain-stem injury. (J.P.N.)

  2. Characterising Ageing in the Human Brainstem Using Quantitative Multimodal MRI Analysis

    Directory of Open Access Journals (Sweden)

    Christian eLambert

    2013-08-01

    Full Text Available Ageing is ubiquitous to the human condition. The MRI correlates of healthy ageing have been extensively investigated using a range of modalities, including volumetric MRI, quantitative MRI and DTI. Despite this, the reported brainstem related changes remain sparse. This is, in part, due to the technical and methodological limitations in quantitatively assessing and statistically analysing this region. By utilising a new method of brainstem segmentation, a large cohort of 100 healthy adults were assessed in this study for the effects of ageing within the human brainstem in vivo. Using quantitative MRI (qMRI, tensor based morphometry (TBM and voxel based quantification (VBQ, the volumetric and quantitative changes across healthy adults between 19-75 years were characterised. In addition to the increased R2* in substantia nigra corresponding to increasing iron deposition with age, several novel findings were reported in the current study. These include selective volumetric loss of the brachium conjunctivum, with a corresponding decrease in magnetisation transfer (MT and increase in proton density (PD, accounting for the previously described midbrain shrinkage. Additionally, we found increases in R1 and PD in several pontine and medullary structures. We consider these changes in the context of well-characterised, functional age-related changes, and propose potential biophysical mechanisms. This study provides detailed quantitative analysis of the internal architecture of the brainstem and provides a baseline for further studies of neurodegenerative diseases that are characterised by early, pre-clinical involvement of the brainstem, such as Parkinson’s and Alzheimer’s diseases.

  3. Assessment of the Brainstem-Mediated Stapedius Muscle Reflex in Andean Children Living at High Altitudes.

    Science.gov (United States)

    Counter, S Allen; Buchanan, Leo H; Ortega, Fernando; Jacobs, Anthony B; Laurell, Göran

    2017-03-01

    Counter, S. Allen, Leo H. Buchanan, Fernando Ortega, Anthony B. Jacobs, and Göran Laurell. Assessment of the brainstem-mediated stapedius muscle reflex in Andean children living at high altitudes. High Alt Med Biol. 18:37-45, 2017.-This study examined the physiological thresholds, amplitude growth, and contraction duration of the acoustic stapedius reflex (ASR) in Andean children aged 2-17 years living at altitudes of 2850 m (Altitude I Group) and 3973 m (Altitude II Group) as part of a general medical assessment of the health status of the children. The brainstem-mediated ASR reveals the integrity of the neuronal components of the auditory reflex arc, including the cochlea receptors, eight cranial nerves, and brainstem neural projections to the cochlear nuclei, bilateral superior olivary nuclei, facial nerve nuclei, and facial nerve and its stapedius branch. Uncrossed (ipsilateral) and crossed (contralateral) ASR thresholds (ASRT), ASR amplitude growth (ASRG) function, and ASR muscle contraction duration (decay/fatigue) (ASRD) were measured noninvasively with 500, 1000 Hz and broadband (bandwidth = 125-4000 Hz) noise stimulus activators using a middle ear immittance system. Oxygen saturation (SaO 2 ) level and heart rate were measured in a subsample of the study group. Statistical analyses revealed that the Altitude I and Altitude II groups had ASRT, ASRG function, and ASRD rates comparable to children at sea level and that the two groups were not significantly different for any of the ASR measures. No significant association was found between SaO 2 or heart rate and ASRT, growth, and muscle fatigue rate. In conclusion, the assessment of the ASR in children in the high-altitude groups revealed normal function. Furthermore, the results indicate no adverse oto-physiological effects of altitude on the brainstem-mediated ASR at elevations between 2850 and 4000 m and suggest normal middle ear and auditory brainstem function.

  4. Optimal technique of linear accelerator-based stereotactic radiosurgery for tumors adjacent to brainstem.

    Science.gov (United States)

    Chang, Chiou-Shiung; Hwang, Jing-Min; Tai, Po-An; Chang, You-Kang; Wang, Yu-Nong; Shih, Rompin; Chuang, Keh-Shih

    2016-01-01

    Stereotactic radiosurgery (SRS) is a well-established technique that is replacing whole-brain irradiation in the treatment of intracranial lesions, which leads to better preservation of brain functions, and therefore a better quality of life for the patient. There are several available forms of linear accelerator (LINAC)-based SRS, and the goal of the present study is to identify which of these techniques is best (as evaluated by dosimetric outcomes statistically) when the target is located adjacent to brainstem. We collected the records of 17 patients with lesions close to the brainstem who had previously been treated with single-fraction radiosurgery. In all, 5 different lesion catalogs were collected, and the patients were divided into 2 distance groups-1 consisting of 7 patients with a target-to-brainstem distance of less than 0.5cm, and the other of 10 patients with a target-to-brainstem distance of ≥ 0.5 and techniques included multiple noncoplanar beams or arcs with or without intensity-modulated delivery. The volume of gross tumor volume (GTV) ranged from 0.2cm(3) to 21.9cm(3). Regarding the dose homogeneity index (HIICRU) and conformity index (CIICRU) were without significant difference between techniques statistically. However, the average CIICRU = 1.09 ± 0.56 achieved by VMAT was the best of the 3 techniques. Moreover, notable improvement in gradient index (GI) was observed when VMAT was used (0.74 ± 0.13), and this result was significantly better than those achieved by the 2 other techniques (p techniques required higher MU delivery than DCA, with the averages being twice as high (p technique for delivering treatment to tumors adjacent to brainstem. Copyright © 2016 American Association of Medical Dosimetrists. All rights reserved.

  5. 1,3-Dinitrobenzene inhibits mitochondrial complex II in rat and mouse brainstem and cortical astrocytes.

    Science.gov (United States)

    Phelka, Amanda D; Beck, Melissa J; Philbert, Martin A

    2003-06-01

    1,3-Dinitrobenzene (DNB) produces edematous, glio-vascular lesions that are initially confined to brainstem nuclei with high energy requirements in rats and mice. Perturbation of energy producing processes in the cell is known to induce formation of the mitochondrial permeability transition pore (mtPTP) complex. Selective vulnerability of brainstem astrocytes to DNB is mediated by a 10-fold lower threshold for opening of the cyclosporin A-inhibitable mitochondrial permeability transition (MPT) pore than their cortical counterparts. Other nitrocompounds, such as 3-nitropropionic acid, selectively interfere with regional energy metabolism, including mitochondrial succinate dehydrogenase activity. However, the link between DNB-induced onset of the MPT and disruption of energy producing processes in the astrocyte remains unclear. The effects of DNB on succinate dehydrogenase activity were evaluated in cultured neonatal rat and mouse brainstem and cortical astrocytes. Both histochemical and spectrophotometric assays confirmed significant temporal inhibition of SDH activity in brainstem and cortical astrocytes 0.5, 2 and 5h following exposure to 100 microM DNB in vitro. Although DNB-induced inhibition of SDH was significantly decreased by CsA pretreatment in brainstem astrocytes after 0.5 and 2h and with a second pore inhibitor, bongkrekic acid (BKA) after 5h, both inhibitors failed to reduce inhibition of SDH activity in cortical astrocytes. These data suggest that DNB-induced inhibition of SDH may be independent of differential regional activation of the mtPTP complex in astrocytes and that an unidentified cyclosporin A-inhibitable factor mediates DNB-induced loss of SDH function.

  6. Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

    Science.gov (United States)

    Wang, Jun Yi; Ngo, Michael M; Hessl, David; Hagerman, Randi J; Rivera, Susan M

    2016-01-01

    Automated segmentation is a useful method for studying large brain structures such as the cerebellum and brainstem. However, automated segmentation may lead to inaccuracy and/or undesirable boundary. The goal of the present study was to investigate whether SegAdapter, a machine learning-based method, is useful for automatically correcting large segmentation errors and disagreement in anatomical definition. We further assessed the robustness of the method in handling size of training set, differences in head coil usage, and amount of brain atrophy. High resolution T1-weighted images were acquired from 30 healthy controls scanned with either an 8-channel or 32-channel head coil. Ten patients, who suffered from brain atrophy because of fragile X-associated tremor/ataxia syndrome, were scanned using the 32-channel head coil. The initial segmentations of the cerebellum and brainstem were generated automatically using Freesurfer. Subsequently, Freesurfer's segmentations were both manually corrected to serve as the gold standard and automatically corrected by SegAdapter. Using only 5 scans in the training set, spatial overlap with manual segmentation in Dice coefficient improved significantly from 0.956 (for Freesurfer segmentation) to 0.978 (for SegAdapter-corrected segmentation) for the cerebellum and from 0.821 to 0.954 for the brainstem. Reducing the training set size to 2 scans only decreased the Dice coefficient ≤0.002 for the cerebellum and ≤ 0.005 for the brainstem compared to the use of training set size of 5 scans in corrective learning. The method was also robust in handling differences between the training set and the test set in head coil usage and the amount of brain atrophy, which reduced spatial overlap only by learning provides a valuable method for accurate and efficient segmentation of the cerebellum and brainstem, particularly in large-scale neuroimaging studies, and potentially for segmenting other neural regions as well.

  7. Key brainstem structures activated during hypoxic exposure in one-day-old mice highlight characteristics for modelling breathing network in premature infants

    Directory of Open Access Journals (Sweden)

    Fanny JOUBERT

    2016-12-01

    Full Text Available We mapped and characterized changes in the activity of brainstem cell groups under hypoxia in one-day-old newborn mice, an animal model in which the central nervous system at birth is particularly immature. The classical biphasic respiratory response characterized by transient hyperventilation, followed by severe ventilation decline, was associated with increased c-FOS immunoreactivity in brainstem cell groups: the nucleus of the solitary tract, ventral reticular nucleus of the medulla, retrotrapezoid/parafacial region, parapyramidal group, raphe magnus nucleus, lateral and medial parabrachial nucleus, and dorsal subcoeruleus nucleus. In contrast, the hypoglossal nucleus displayed decreased c-FOS immunoreactivity. There were fewer or no activated catecholaminergic cells activated in the medulla oblongata, whereas approximately 45% of the c-FOS-positive cells in the dorsal subcoeruleus were co-labelled. Approximately 30% of the c-FOS-positive cells in the parapyramidal group were serotoninergic, whereas only a small portion were labelled for serotonin in the raphe magnus nucleus. None of the c-FOS-positive cells in the retrotrapezoid/parafacial region were co-labelled for PHOX2B. Thus, the hypoxia-activated brainstem neuronal network of one-day-old mice is characterized by i the activation of catecholaminergic cells of the dorsal subcoeruleus nucleus, a structure implicated in the strong depressive pontine influence previously reported in the fetus but not in newborns, ii the weak activation of catecholaminergic cells of the ventral reticular nucleus of the medulla, an area involved in hypoxic hyperventilation, and iii the absence of PHOX2B-positive cells activated in the retrotrapezoid/parafacial region. Based on these results, one-day-old mice could highlight characteristics for modelling the breathing network of premature infants.

  8. Modulation of oxidative responses by a virulent isolate of Colletotrichum fructicola in apple leaves.

    Science.gov (United States)

    Velho, Aline Cristina; Rockenbach, Mathias F; Mondino, Pedro; Stadnik, Marciel J

    2016-10-01

    Apple bitter rot (ABR) and Glomerella leaf spot (GLS) can be caused by Colletotrichum fructicola. Although both diseases can occur simultaneously in orchards, some isolates show clear organ specialization. Thus, this work was aimed to compare microscopically the development of preinfective structures of ABR- and GLS isolates and their impact on the enzymatic oxidant defense system during the leaf infection process. On leaves, conidial germlings of GLS-isolate formed appressoria mostly sessile. In contrast, those of ABR-isolate were pedicellate and formed multiple melanized appressoria probably as a sign of unsuccessful infection attempts. Neither ABR- nor GLS isolate triggered hypersensitive response in apple leaves. In overall, the activity of scavenging enzymes was higher and long-lasting in leaves inoculated by GLS- than by ABR isolate and control. Guaiacol peroxidase, catalase, and glutathione reductase had activity peaks within 24 h after inoculation (HAI). Ascorbate peroxidase activity was higher only in GLS-infected leaves at 6 HAI, while superoxide dismutase remained unaltered. A lower level of hydrogen peroxide (H2O2) was determined in GLS-infected plants at 48 HAI, but the electrolyte leakage markedly increased. Disease symptoms in leaves were only caused by GLS-isolate. Results suggest that the virulent isolate coordinately downregulates the oxidative plant defense responses enabling its successful establishment in apple leaves. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  9. Improved mapping and quantification of serotonin transporter availability in the human brainstem with the HRRT.

    Science.gov (United States)

    Schain, Martin; Tóth, Miklós; Cselényi, Zsolt; Arakawa, Ryosuke; Halldin, Christer; Farde, Lars; Varrone, Andrea

    2013-01-01

    The serotonin system is involved in many physiological functions and clinical conditions. Serotonergic neurons originate from the raphe nuclei in the brainstem, and reliable estimates of receptor/transporter availability in the raphe in vivo are thus of interest. Though positron emission tomography (PET) can be used to quantify receptor distribution in the brain, high noise levels prevent reliable estimation of radioligand binding in small regions such as the raphe. For this purpose, parametric imaging in combination with high-resolution PET systems may provide images with reduced noise levels and sufficient contrast for reliable quantification. This study examined the potential to evaluate radioligand binding in brainstem nuclei, and assessed the effect of improved resolution on the outcome measures. For comparative purposes, radioligand binding was measured with an ECAT EXACT HR PET system (resolution about 4.5 mm FWHM) and a high-resolution research tomograph (HRRT) system (resolution about 1.5 mm FWHM). Six subjects were examined with both systems on the same day using the serotonin transporter radioligand [(11)C]MADAM. Parametric images of binding potential (BP (ND)) were obtained using a wavelet-aided approach. Regions of interest (ROIs) were delineated using a threshold-based semiautomatic delineation procedure for five brainstem structures. Regional BP (ND) values were estimated by applying the ROIs to the parametric images, and the percentage difference in BP (ND) between the systems was calculated. Signals for [(11)C]MADAM binding were obtained for all five brainstem structures. Overall, the HRRT provided 30-40 % higher BP (ND) values than the HR (p = 0.0017), independent of thresholds used in the ROI delineation procedure. The methodology used enabled the estimation of [(11)C]MADAM binding in the small nuclei of the brainstem. Differences in the BP (ND) values calculated using data from the two systems were mainly attributable to their differing

  10. Auditory Screening in Infants for Early Detection of Permanent ...

    African Journals Online (AJOL)

    Both the auditory brainstem response (ABR) and the otoacoustic emission (OAE) test are used to screen hearing in newborns.[9,10] The OAE test measures the response ... prevalence of hearing loss in this study, implementation of a universal newborn hearing ... In the healthy cochlea, vibration of the hair cells in response.

  11. Category-specific visual responses: an intracranial study comparing gamma, beta, alpha and ERP response selectivity

    Directory of Open Access Journals (Sweden)

    Juan R Vidal

    2010-11-01

    Full Text Available The specificity of neural responses to visual objects is a major topic in visual neuroscience. In humans, functional magnetic resonance imaging (fMRI studies have identified several regions of the occipital and temporal lobe that appear specific to faces, letter-strings, scenes, or tools. Direct electrophysiological recordings in the visual cortical areas of epileptic patients have largely confirmed this modular organization, using either single-neuron peri-stimulus time-histogram or intracerebral event-related potentials (iERP. In parallel, a new research stream has emerged using high-frequency gamma-band activity (50-150 Hz (GBR and low-frequency alpha/beta activity (8-24 Hz (ABR to map functional networks in humans. An obvious question is now whether the functional organization of the visual cortex revealed by fMRI, ERP, GBR, and ABR coincide. We used direct intracerebral recordings in 18 epileptic patients to directly compare GBR, ABR, and ERP elicited by the presentation of seven major visual object categories (faces, scenes, houses, consonants, pseudowords, tools, and animals, in relation to previous fMRI studies. Remarkably both GBR and iERP showed strong category-specificity that was in many cases sufficient to infer stimulus object category from the neural response at single-trial level. However, we also found a strong discrepancy between the selectivity of GBR, ABR, and ERP with less than 10% of spatial overlap between sites eliciting the same category-specificity. Overall, we found that selective neural responses to visual objects were broadly distributed in the brain with a prominent spatial cluster located in the posterior temporal cortex. Moreover, the different neural markers (GBR, ABR, and iERP that elicit selectivity towards specific visual object categories present little spatial overlap suggesting that the information content of each marker can uniquely characterize high-level visual information in the brain.

  12. Sequential change in MRI in two cases with small brainstem infarctions

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Ryoichi; Fukuda, Osamu; Endoh, Shunro; Takaku, Akira; Suzuki, Takashi; Satoh, Shuji

    1987-12-01

    Magnetic resonance imaging (MRI) has been found to be very useful for the diagnosis of a small brainstem infarction. However, most reported cases have shown the changes at only the chronic stage. In this report, sequential changes in the MRI in two cases with small brainstem infarctions are presented. In Case 1, a 67-year-old man with a pure sensory stroke on the right side, a small infarcted area was observed at the left medial side of the pontomedullary junction on MRI. In Case 2, a 62-year-old man with a pure motor hemiparesis of the left side, MRI revealed a small infarcted area on the right ventral of the middle pons. The initial changes were confirmed 5 days (Case 1) and 18 hours (Case 2) after the onset of the completed stroke. No abnormal findings could be found in the computed tomography in either case.

  13. Endovascular treatment of brain-stem arteriovenous malformations: safety and efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.M.; Wang, Y.H.; Chen, Y.F.; Huang, K.M. [Department of Medical Imaging, National Taiwan University Hospital, 7 Chung-Shan South Road, 10016, Taipei (Taiwan); Tu, Y.K. [Division of Neurosurgery, Department of Surgery, National Taiwan University Hospital, 7 Chung-Shan South Road, 1001, Taipei (Taiwan)

    2003-09-01

    Our purpose was to evaluate the safety and efficacy of endovascular treatment of brain-stem arteriovenous malformations (AVMs), reviewing six cases managed in the last 5 years. There were four patients who presented with bleeding, one with a progressive neurological deficit and one with obstructive hydrocephalus. Of the six patients, one showed 100%, one 90%, two 75% and two about 50% angiographic obliteration of the AVM after embolisation; the volume decreased about 75% on average. Five patients had a good outcome and one an acceptable outcome, with a mild postprocedure neurological deficit; none had further bleeding during midterm follow-up. Endovascular management of a brain-stem AVM may be an alternative to treatment such as radiosurgery and microsurgery in selected cases. It may be not as risky as previously thought. Embolisation can reduce the size of the AVM and possibly make it more treatable by radiosurgery and decrease the possibility of radiation injury. (orig.)

  14. The vascular territories in the infaraction of the cerebellum and brainstem: CT study

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Kyung Nam; Choi, Woo Suk; Lee, Sun Wha; Lim, Jae Hoon [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1988-04-15

    Of 11,779 consecutive CT examinations of the head, 74 patients of infarctions in the cerebellum and brainstem were retrospectively reviewed to define the most typical distribution of infarctions in the different vascular territories. More limitation for knowledge of vascular territory. Of 74 cases, 41 were male and 33 were female, and the age ranged from 2nd to 8th decades. Of 74 cases, the lesion of PICA territory was observed in 29 cases(38%), SCA territory in 26(36%), brainstem in 25(34%) and watershed zone in 14(19%), Twenty-one cases have infarctions of two different vascular territories. The SCA territory is the most extensive territory and includes the largest part of the deep white matter.

  15. Hypertensive brainstem encephalopathy involving deep supratentorial regions: does only blood pressure matter?

    Directory of Open Access Journals (Sweden)

    Jong-Ho Park

    2010-04-01

    Full Text Available We report on a 42-year-old female patient who presented with high arterial blood pressure of 245/150 mmHg and hypertensive brainstem encephalopathy that involved the brainstem and extensive supratentorial deep gray and white matter. The lesions were nearly completely resolved several days after stabilization of the arterial blood pressure. Normal diffusion-weighted imaging findings and high apparent diffusion coefficient values suggested that the main pathomechanism was vasogenic edema owing to severe hypertension. On the basis of a literature review, the absolute value of blood pressure or whether the patient can control his/her blood pressure seems not to be associated with the degree of the lesions evident on magnetic resonance imaging. It remains to be determined if the acceleration rate and the duration of elevated arterial blood pressure might play a key role in the development of the hypertensive encephalopathy pattern.

  16. Auditory brain stem responses in the detection of brain death.

    Science.gov (United States)

    Ozgirgin, O Nuri; Ozçelik, Tuncay; Sevimli, Nilay Kizilkaya

    2003-01-01

    We evaluated comatose patients by auditory brain stem responses (ABR) to determine the role of ABR in the diagnosis of impending brain death. Sixty comatose patients in the intensive care unit were evaluated by brain stem evoked response audiometry. Correlations were sought between the absence or presence of ABRs and the presenting pathology, the Glasgow Coma Scale (GCS) scores, and ultimate diagnoses. The brain stem responses were totally absent in 41 patients. Presence of wave I could be obtained in only 10 patients. All the waveforms were found in nine patients; however, in eight patients the potentials disappeared as the GCS scores decreased to 3. Detection of wave I alone strongly suggested dysfunction of the brain stem. However, loss of wave I particularly in trauma patients aroused doubt as to whether the absence was associated with auditory end organ injury or brain stem dysfunction. The results suggest that evaluation of ABR may support brain death in a comatose patient (i) when wave I is present alone, (ii) the absence of wave I is accompanied by a documented auditory end organ injury, or (iii) when previously recorded potentials are no longer detectable.

  17. Multi-sensory integration in brainstem and auditory cortex.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience

  18. Depressive disorder may be associated with raphe nuclei lesions in patients with brainstem infarction.

    Science.gov (United States)

    Numasawa, Yoshiyuki; Hattori, Takaaki; Ishiai, Sumio; Kobayashi, Zen; Kamata, Tomoyuki; Kotera, Minoru; Ishibashi, Satoru; Sanjo, Nobuo; Mizusawa, Hidehiro; Yokota, Takanori

    2017-04-15

    Depression is a common symptom after stroke, but its neural substrates remain unclear. The ascending serotonergic system originates from the raphe nuclei in the brainstem. We hypothesized that depressive disorder due to brainstem infarction is associated with damage to the raphe nuclei. We prospectively enrolled 19 patients who had the first-ever acute isolated brainstem infarction in an observational cross-sectional study. All patients were evaluated by using the Montgomery Åsberg Depression Rating Scale (MADRS), the clinician-rated version of Apathy Evaluation Scale (AES-C) and Mini-Mental State Examination (MMSE). Depressive disorder was diagnosed according to DSM-5 and MADRS score of 12 or greater. Diffusion tensor imaging and proton density-weighted images were used to identify damage in the raphe nuclei. Accordingly, patients were classified into either the raphe-nuclei-damaged or intact group. Prevalence of depressive disorder and the MADRS, AES-C, and MMSE scores were compared between the two groups. Depressive disorder was more frequent in the damaged group (n=6) than in the intact group (n=13) (83% vs. 15%; P=0.01). MADRS scores were higher in the damaged group than in the intact group (mean±1 SD, 17.5±7.9 vs. 7.0±4.4; P=0.002), whereas the AES-C and MMSE scores did not differ between groups. We did not assess the damage to the ascending projection fibers from the raphe nuclei. Our results suggest that damage to the raphe nuclei underlies depressive disorder due to brainstem infarction, possibly via serotonergic denervation. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Retrospective analysis of 104 histologically proven adult brainstem gliomas: clinical symptoms, therapeutic approaches and prognostic factors

    International Nuclear Information System (INIS)

    Reithmeier, Thomas; Kuzeawu, Aanyo; Hentschel, Bettina; Loeffler, Markus; Trippel, Michael; Nikkhah, Guido

    2014-01-01

    Adult brainstem gliomas are rare primary brain tumors (<2% of gliomas). The goal of this study was to analyze clinical, prognostic and therapeutic factors in a large series of histologically proven brainstem gliomas. Between 1997 and 2007, 104 patients with a histologically proven brainstem glioma were retrospectively analyzed. Data about clinical course of disease, neuropathological findings and therapeutic approaches were analyzed. The median age at diagnosis was 41 years (range 18-89 years), median KPS before any operative procedure was 80 (range 20-100) and median survival for the whole cohort was 18.8 months. Histopathological examinations revealed 16 grade I, 31 grade II, 42 grade III and 14 grade IV gliomas. Grading was not possible in 1 patient. Therapeutic concepts differed according to the histopathology of the disease. Median overall survival for grade II tumors was 26.4 months, for grade III tumors 12.9 months and for grade IV tumors 9.8 months. On multivariate analysis the relative risk to die increased with a KPS ≤ 70 by factor 6.7, with grade III/IV gliomas by the factor 1.8 and for age ≥ 40 by the factor 1.7. External beam radiation reduced the risk to die by factor 0.4. Adult brainstem gliomas present with a wide variety of neurological symptoms and postoperative radiation remains the cornerstone of therapy with no proven benefit of adding chemotherapy. Low KPS, age ≥ 40 and higher tumor grade have a negative impact on overall survival

  20. Brainstem shape is affected by clinical course in the neonatal intensive care unit

    Directory of Open Access Journals (Sweden)

    Marcus Lo

    2017-01-01

    Full Text Available The brainstem, critical for motor function, autonomic regulation, and many neurocognitive functions, undergoes rapid development from the third trimester. Accordingly, we hypothesized it would be vulnerable to insult during this period, and that a difficult clinical course in the neonatal intensive care unit (NICU would affect development, and be reflected through atypical shape. Our study population consisted of 66 neonates – all inpatients from the NICU at Victoria Hospital, London Health Sciences Centre, ON, Canada, of which 45 entered the final analysis. The cohort varied in gestational age (GA and ranged from neurologically healthy to severely brain-injured. Structural MRI was used to quantify brainstem shape at term-equivalent age. From these images, brainstems were semi-automatically segmented and co-registered across subjects. The anterior-posterior dimensions on a sagittal maximum intensity projection were used as the basis for shape comparison. Factor analysis was used to summarize variation in shape and in clinical course to determine three shape factors and three clinical factors, and their relationship assessed using correlation. A factor driven by low GA and associated complications correlated with alterations in the posterior medulla, while a factor driven by complications independent of GA correlated with alterations in the midbrain. Additionally, single clinical measures most representative of their respective clinical factor (days in NICU; days on ventilation predicted the changes. Thus, different clinical courses in the NICU may have different effects on the shape of the brainstem, and may mediate some of the distinct neurodevelopmental profiles observed in premature and brain-injured neonates.

  1. Limbic encephalitis with antibodies to glutamic acid decarboxylase presenting with brainstem symptoms

    Directory of Open Access Journals (Sweden)

    Faruk Incecik

    2015-01-01

    Full Text Available Limbic encephalitis (LE is a neurological syndrome that may present in association with cancer, infection, or as an isolate clinical condition often accompanying autoimmune disorders. LE associated with glutamic acid decarboxylase antibodies (anti-GAD is rare in children. Here, we characterized the clinical and laboratory features of a patient presenting with brainstem involvement with non-paraneoplastic LE associated with anti-GAD antibodies. In our patient, after plasma exchange, we determined a dramatic improvement of the neurological deficits.

  2. 1.5-T high-resolution MR imaging of oculomotor disturbances due to intrinsic brain-stem disease

    International Nuclear Information System (INIS)

    Patel, S.C.; Quint, D.J.; Sanders, W.P.; Mehta, B.A.; Boulos, R.S.; Froelich, J.W.

    1987-01-01

    Seventeen patients who presented with oculomotor disturbances (internuclear ophthalmoplegia, ophthalmoparesis) underwent MR imaging, which demonstrated brain-stem abnormalities in 11 cases. Lesions identified included occult vascular malformation with hemorrhage (two), hypertensive hemorrhage (one), infarction (two), neoplasm (two), and demyelinating disease (four). The authors' exhibit illustrates the exquisite anatomic detail displayed by high-field MR imaging in localizing various intrinsic brain-stem lesions in the region of the third, fourth, and sixth cranial nuclei and the medial longitudinal fasciculus

  3. Population calcium imaging of spontaneous respiratory and novel motor activity in the facial nucleus and ventral brainstem in newborn mice

    DEFF Research Database (Denmark)

    Persson, Karin; Rekling, Jens C

    2011-01-01

    The brainstem contains rhythm and pattern forming circuits, which drive cranial and spinal motor pools to produce respiratory and other motor patterns. Here we used calcium imaging combined with nerve recordings in newborn mice to reveal spontaneous population activity in the ventral brainstem...... in lateral and medial subnuclei. Whole-cell recordings from facial motoneurons showed weak respiratory drives, and electrical field potential recordings confirmed respiratory drive to particularly the dorsal and lateral subnuclei. Putative facial premotoneurons showed respiratory-related calcium signals...

  4. Autopsy Findings of Brainstem in Head Trauma in Comparison with CT Scan Findings in Brain Trauma Ward in Tabriz, Iran

    OpenAIRE

    Shakeri Bavil Moslem; Ashrafian Fereydun; Daghighi Mohammad Ali; Samadi Rad Bahram; Zeinali Ali

    2009-01-01

    Computed tomography (CT) is now the primary diagnostic method for head trauma because of its ability to demonstrate the nature, extent, sites, and multiplicity of brain injuries. Although there have been numerous reports on the CT findings of most types of intracranial injury, the findings in brainstem injury have not been well described. This study aimed at comparing the autopsy findings of brainstem in head trauma in comparison with CT scan results. Two hundred patients with head trauma, wh...

  5. The maturation state of the auditory nerve and brainstem in rats exposed to lead acetate and supplemented with ferrous sulfate.

    Science.gov (United States)

    Zucki, Fernanda; Morata, Thais C; Duarte, Josilene L; Ferreira, Maria Cecília F; Salgado, Manoel H; Alvarenga, Kátia F

    The literature has reported the association between lead and auditory effects, based on clinical and experimental studies. However, there is no consensus regarding the effects of lead in the auditory system, or its correlation with the concentration of the metal in the blood. To investigate the maturation state of the auditory system, specifically the auditory nerve and brainstem, in rats exposed to lead acetate and supplemented with ferrous sulfate. 30 weanling male rats (Rattus norvegicus, Wistar) were distributed into six groups of five animals each and exposed to one of two concentrations of lead acetate (100 or 400mg/L) and supplemented with ferrous sulfate (20mg/kg). The maturation state of the auditory nerve and brainstem was analyzed using Brainstem Auditory Evoked Potential before and after lead exposure. The concentration of lead in blood and brainstem was analyzed using Inductively Coupled Plasma-Mass Spectrometry. We verified that the concentration of Pb in blood and in brainstem presented a high correlation (r=0.951; p<0.0001). Both concentrations of lead acetate affected the maturation state of the auditory system, being the maturation slower in the regions corresponding to portion of the auditory nerve (wave I) and cochlear nuclei (wave II). The ferrous sulfate supplementation reduced significantly the concentration of lead in blood and brainstem for the group exposed to the lowest concentration of lead (100mg/L), but not for the group exposed to the higher concentration (400mg/L). This study indicate that the lead acetate can have deleterious effects on the maturation of the auditory nerve and brainstem (cochlear nucleus region), as detected by the Brainstem Auditory Evoked Potentials, and the ferrous sulphate can partially amend this effect. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. All rights reserved.

  6. Prenatal nicotine exposure enhances the trigeminocardiac reflex via serotonin receptor facilitation in brainstem pathways.

    Science.gov (United States)

    Gorini, C; Jameson, H; Woerman, A L; Perry, D C; Mendelowitz, D

    2013-08-15

    In this study we used a rat model for prenatal nicotine exposure to test whether clinically relevant concentrations of brain nicotine and cotinine are passed from dams exposed to nicotine to her pups, whether this changes the trigeminocardiac reflex (TCR), and whether serotonergic function in the TCR brainstem circuitry is altered. Pregnant Sprague-Dawley dams were exposed to 6 mg·kg(-1)·day(-1) of nicotine via osmotic minipumps for the duration of pregnancy. Following birth dams and pups were killed, blood was collected, and brain nicotine and cotinine levels were measured. A separate group of prenatal nicotine-exposed pups was used for electrophysiological recordings. A horizontal brainstem slice was obtained by carefully preserving the trigeminal nerve with fluorescent identification of cardiac vagal neurons (CVNs) in the nucleus ambiguus. Stimulation of the trigeminal nerve evoked excitatory postsynaptic current in CVNs. Our data demonstrate that prenatal nicotine exposure significantly exaggerates both the TCR-evoked changes in heart rate in conscious unrestrained pups, and the excitatory neurotransmission to CVNs upon trigeminal afferent nerve stimulation within this brainstem reflex circuit. Application of the 5-HT1A receptor antagonist WAY 100635 (100 μM) and 5-HT2A/C receptor antagonist ketanserin (10 μM)significantly decreased neurotransmission, indicating an increased facilitation of 5-HT function in prenatal nicotine-exposed animals. Prenatal nicotine exposure enhances activation of 5-HT receptors and exaggerates the trigeminocardiac reflex.

  7. Blast overpressure induced axonal injury changes in rat brainstem and spinal cord

    Directory of Open Access Journals (Sweden)

    Srinivasu Kallakuri

    2015-01-01

    Full Text Available Introduction: Blast induced neurotrauma has been the signature wound in returning soldiers from the ongoing wars in Iraq and Afghanistan. Of importance is understanding the pathomechansim(s of blast overpressure (OP induced axonal injury. Although several recent animal models of blast injury indicate the neuronal and axonal injury in various brain regions, animal studies related to axonal injury in the white matter (WM tracts of cervical spinal cord are limited. Objective: The purpose of this study was to assess the extent of axonal injury in WM tracts of cervical spinal cord in male Sprague Dawley rats subjected to a single insult of blast OP. Materials and Methods: Sagittal brainstem sections and horizontal cervical spinal cord sections from blast and sham animals were stained by neurofilament light (NF-L chain and beta amyloid precursor protein immunocytochemistry and observed for axonal injury changes. Results: Observations from this preliminary study demonstrate axonal injury changes in the form of prominent swellings, retraction bulbs, and putative signs of membrane disruptions in the brainstem and cervical spinal cord WM tracts of rats subjected to blast OP. Conclusions: Prominent axonal injury changes following the blast OP exposure in brainstem and cervical spinal WM tracts underscores the need for careful evaluation of blast induced injury changes and associated symptoms. NF-L immunocytochemistry can be considered as an additional tool to assess the blast OP induced axonal injury.

  8. Endoscopic third ventriculostomy for hydrocephalus in brainstem glioma: a case series.

    Science.gov (United States)

    Kobayashi, Natsuki; Ogiwara, Hideki

    2016-07-01

    A brainstem glioma is an incurable brain tumor that can be complicated by hydrocephalus. A ventriculoperitoneal (VP) shunt is generally performed for the control of hydrocephalus. This study aimed to reveal the safety and efficacy of an endoscopic third ventriculostomy (ETV) for hydrocephalus in brainstem gliomas. Six patients who had pontine glioma with hydrocephalus underwent an ETV between May 2010 and November 2015. In all the cases, there were one or more symptoms of hydrocephalus (headache, nausea, vomiting, or lethargy). Retrospective review of these patients was performed using the medical records and neuroimagings. The ETV was performed safely and there were no intraoperative complications in all patients. The mean follow-up period was 12.3 months. An immediate symptomatic relief of hydrocephalus and an adequate control of symptoms were achieved without a VP shunt in all patients. The ETV is considered to be an effective and safe procedure for the treatment of hydrocephalus in brainstem gliomas. Determining the ventriculostomy site according to the preoperative MRI in each case is considered to be important for the safe procedure.

  9. Gamma Knife Radiosurgery Treatment for Metastatic Melanoma of the Trigeminal Nerve and Brainstem: A Case Report and a Review of the Literature

    Directory of Open Access Journals (Sweden)

    Halloran E. Peterson

    2013-01-01

    Full Text Available Objective and Importance. Brainstem metastases (BSMs are uncommon but serious complications of some cancers. They cause significant neurological deficit, and options for treatment are limited. Stereotactic radiosurgery (SRS has been shown to be a safe and effective treatment for BSMs that prolongs survival and can preserve or in some cases improve neurological function. This case illustrates the use of repeated SRS, specifically Gamma Knife radiosurgery (GKRS for management of a unique brainstem metastasis. Clinical Presentation. This patient presented 5 years after the removal of a lentigo maligna melanoma from her left cheek with left sided facial numbness and paresthesias with no reported facial weakness. Initial MRI revealed a mass on the left trigeminal nerve that appeared to be a trigeminal schwannoma. Intervention. After only limited response to the first GKRS treatment, a biopsy of the tumor revealed it to be metastatic melanoma, not schwannoma. Over the next two years, the patient would receive 3 more GKRS treatments. These procedures were effective in controlling growth in the treated areas, and the patient has maintained a good quality of life. Conclusion. GKRS has proven in this case to be effective in limiting the growth of this metastatic melanoma without acute adverse effects.

  10. Hypoxia attenuates purinergic P2X receptor-induced inflammatory gene expression in brainstem microglia

    Directory of Open Access Journals (Sweden)

    Smith SMC

    2013-08-01

    Full Text Available Stephanie MC Smith,1,2 Gordon S Mitchell,1,2 Scott A Friedle,3 Christine M Sibigtroth,1 Stéphane Vinit,1 Jyoti J Watters1–31Department of Comparative Biosciences, 2Comparative Biomedical Sciences Training Program, 3Program in Cellular and Molecular Biology, University of Wisconsin, Madison, WI, USAAbstract: Hypoxia and increased extracellular nucleotides are frequently coincident in the brainstem. Extracellular nucleotides are potent modulators of microglial inflammatory gene expression via P2X purinergic receptor activation. Although hypoxia is also known to modulate inflammatory gene expression, little is known about how hypoxia or P2X receptor activation alone affects inflammatory molecule production in brainstem microglia, nor how hypoxia and P2X receptor signaling interact when they occur together. In the study reported here, we investigated the ability of a brief episode of hypoxia (2 hours in the presence and absence of the nonselective P2X receptor agonist 2′(3′-O-(4-benzoylbenzoyladenosine-5′-triphosphate (BzATP to promote inflammatory gene expression in brainstem microglia in adult rats. We evaluated inducible nitric oxide synthase (iNOS, tumor necrosis factor alpha (TNFα, and interleukin (IL-6 messenger RNA levels in immunomagnetically isolated brainstem microglia. While iNOS and IL-6 gene expression increased with hypoxia and BzATP alone, TNFα expression was unaffected. Surprisingly, BzATP-induced inflammatory effects were lost after hypoxia, suggesting that hypoxia impairs proinflammatory P2X-receptor signaling. We also evaluated the expression of key P2X receptors activated by BzATP, namely P2X1, P2X4, and P2X7. While hypoxia did not alter their expression, BzATP upregulated P2X4 and P2X7 mRNAs; these effects were ablated in hypoxia. Although both P2X4 and P2X7 receptor expression correlated with increased microglial iNOS and IL-6 levels in microglia from normoxic rats, in hypoxia, P2X7 only correlated with IL-6, and P2X

  11. Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

    Directory of Open Access Journals (Sweden)

    Jun Yi Wang

    Full Text Available Automated segmentation is a useful method for studying large brain structures such as the cerebellum and brainstem. However, automated segmentation may lead to inaccuracy and/or undesirable boundary. The goal of the present study was to investigate whether SegAdapter, a machine learning-based method, is useful for automatically correcting large segmentation errors and disagreement in anatomical definition. We further assessed the robustness of the method in handling size of training set, differences in head coil usage, and amount of brain atrophy. High resolution T1-weighted images were acquired from 30 healthy controls scanned with either an 8-channel or 32-channel head coil. Ten patients, who suffered from brain atrophy because of fragile X-associated tremor/ataxia syndrome, were scanned using the 32-channel head coil. The initial segmentations of the cerebellum and brainstem were generated automatically using Freesurfer. Subsequently, Freesurfer's segmentations were both manually corrected to serve as the gold standard and automatically corrected by SegAdapter. Using only 5 scans in the training set, spatial overlap with manual segmentation in Dice coefficient improved significantly from 0.956 (for Freesurfer segmentation to 0.978 (for SegAdapter-corrected segmentation for the cerebellum and from 0.821 to 0.954 for the brainstem. Reducing the training set size to 2 scans only decreased the Dice coefficient ≤0.002 for the cerebellum and ≤ 0.005 for the brainstem compared to the use of training set size of 5 scans in corrective learning. The method was also robust in handling differences between the training set and the test set in head coil usage and the amount of brain atrophy, which reduced spatial overlap only by <0.01. These results suggest that the combination of automated segmentation and corrective learning provides a valuable method for accurate and efficient segmentation of the cerebellum and brainstem, particularly in large

  12. Proceedings of the U.S. Army Chemical Research, Development and Engineering Center Scientific Conference on Chemical Defense Research Held in Aberdeen Proving Ground, Maryland on 14-17 November 1989

    Science.gov (United States)

    1990-08-01

    demonstrating brainstem dysfunction in preterm infants subject to apnea . It was hypothesized that ABRs would be a sensitive indicator of the effects of...Campbell, D.J.: Clinical apnea and brain stem neural function in preterm infants. N_ Engl. J. Med. 308:353-357, 1983. 2. Reutter, S.A.: Brainstem Evoked...Responses and Apnea in Preterm Infants, PhD Dissertation, George Washington Univ., Washington, DC, 1985. 1 Toxicology Division, U.S, Army Chemical

  13. c-Fos induction by a 14 T magnetic field in visceral and vestibular relays of the female rat brainstem is modulated by estradiol.

    Science.gov (United States)

    Cason, Angie M; Kwon, Bumsup; Smith, James C; Houpt, Thomas A

    2010-08-06

    There is increasing evidence that high magnetic fields interact with the vestibular system of humans and rodents. In rats, exposure to high magnetic fields of 7 T or above induces locomotor circling and leads to a conditioned taste aversion if paired with a novel taste. Sex differences in the behavioral responses to magnetic field exposure have been found, such that female rats show more locomotor circling and enhanced conditioned taste aversion compared to male rats. To determine if estrogen modulates the neural response to high magnetic fields, c-Fos expression after 14 T magnetic field exposure was compared in ovariectomized rats and ovariectomized rats with estradiol replacement. Compared to sham exposure, magnetic field exposure induced significantly more c-Fos positive cells in the nucleus of the solitary tract and the parabrachial, medial vestibular, prepositus, and supragenualis nuclei. Furthermore, there was a significant asymmetry in c-Fos induction between sides of the brainstem in several regions. In ovariectomized rats, there was more c-Fos expressed in the right side compared to left side in the locus coeruleus and parabrachial, superior vestibular, and supragenualis nuclei; less expression in the right compared to left side of the medial vestibular; and no asymmetry in the prepositus nucleus and the nucleus of the solitary tract. Chronic estradiol treatment modulated the neural response in some regions: less c-Fos was induced in the superior vestibular nucleus and locus coeruleus after estradiol replacement; estradiol treatment eliminated the asymmetry of c-Fos expression in the locus coeruleus and supragenualis nucleus, created an asymmetry in the prepositus nucleus and reversed the asymmetry in the parabrachial nucleus. These results suggest that ovarian steroids may mediate sex differences in the behavioral responses to magnetic field exposure at the level of visceral and vestibular nuclei of the brainstem. Copyright 2010 Elsevier B.V. All rights

  14. c-Fos induction by a 14T magnetic field in visceral and vestibular relays of the female rat brainstem is modulated by estradiol

    Science.gov (United States)

    Cason, Angie M.; Kwon, Bumsup; Smith, James C.; Houpt, Thomas A.

    2010-01-01

    There is increasing evidence that high magnetic fields interact with the vestibular system of humans and rodents. In rats, exposure to high magnetic fields of 7T or above induces locomotor circling and leads to a conditioned taste aversion if paired with a novel taste. Sex differences in the behavioral responses to magnetic field exposure have been found, such that female rats show more locomotor circling and enhanced conditioned taste aversion compared to male rats. To determine if estrogen modulates the neural response to high magnetic fields, c-Fos expression after 14T magnetic field exposure was compared in ovariectomized rats and ovariectomized rats with estradiol replacement. Compared to sham exposure, magnetic field exposure induced significantly more c-Fos positive cells in the nucleus of the solitary tract and the parabrachial, medial vestibular, prepositus, and supragenualis nuclei. Furthermore, there was a significant asymmetry in c-Fos induction between sides of the brainstem in several regions. In ovariectomized rats, there was more c-Fos expressed in the right side compared to left side in the locus coeruleus and parabrachial, superior vestibular, and supragenualis nuclei; less expression in the right compared to left side of the medial vestibular; and no asymmetry in the prepositus nucleus and the nucleus of the solitary tract. Chronic estradiol treatment modulated the neural response in some regions: less c-Fos was induced in the superior vestibular nucleus and locus coeruleus after estradiol replacement; estradiol treatment eliminated the asymmetry of c-Fos expression in the locus coeruleus and supragenualis nucleus, created an asymmetry in the prepositus nucleus and reversed the asymmetry in the parabrachial nucleus. These results suggest that ovarian steroids may mediate sex differences in the behavioral responses to magnetic field exposure at the level of visceral and vestibular nuclei of the brainstem. PMID:20553875

  15. Transgenic quail as a model for research in the avian nervous system: a comparative study of the auditory brainstem.

    Science.gov (United States)

    Seidl, Armin H; Sanchez, Jason Tait; Schecterson, Leslayann; Tabor, Kathryn M; Wang, Yuan; Kashima, Daniel T; Poynter, Greg; Huss, David; Fraser, Scott E; Lansford, Rusty; Rubel, Edwin W

    2013-01-01

    Research performed on transgenic animals has led to numerous advances in biological research. However, using traditional retroviral methods to generate transgenic avian research models has proved problematic. As a result, experiments aimed at genetic manipulations on birds have remained difficult for this popular research tool. Recently, lentiviral methods have allowed the production of transgenic birds, including a transgenic Japanese quail (Coturnix coturnix japonica) line showing neuronal specificity and stable expression of enhanced green fluorescent protein (eGFP) across generations (termed here GFP quail). To test whether the GFP quail may serve as a viable alternative to the popular chicken model system, with the additional benefit of genetic manipulation, we compared the development, organization, structure, and function of a specific neuronal circuit in chicken (Gallus gallus domesticus) with that of the GFP quail. This study focuses on a well-defined avian brain region, the principal nuclei of the sound localization circuit in the auditory brainstem, nucleus magnocellularis (NM), and nucleus laminaris (NL). Our results demonstrate that structural and functional properties of NM and NL neurons in the GFP quail, as well as their dynamic properties in response to changes in the environment, are nearly identical to those in chickens. These similarities demonstrate that the GFP quail, as well as other transgenic quail lines, can serve as an attractive avian model system, with the advantage of being able to build on the wealth of information already available from the chicken. Copyright © 2012 Wiley Periodicals, Inc.

  16. Population calcium imaging of spontaneous respiratory and novel motor activity in the facial nucleus and ventral brainstem in newborn mice.

    Science.gov (United States)

    Persson, Karin; Rekling, Jens C

    2011-05-15

    The brainstem contains rhythm and pattern forming circuits, which drive cranial and spinal motor pools to produce respiratory and other motor patterns. Here we used calcium imaging combined with nerve recordings in newborn mice to reveal spontaneous population activity in the ventral brainstem and in the facial nucleus. In Fluo-8AM loaded brainstem-spinal cord preparations, respiratory activity on cervical nerves was synchronized with calcium signals at the ventrolateral brainstem surface. Individual ventrolateral neurons at the level of the parafacial respiratory group showed perfect or partial synchrony with respiratory nerve bursts. In brainstem-spinal cord preparations, cut at the level of the mid-facial nucleus, calcium signals were recorded in the dorsal, lateral and medial facial subnuclei during respiratory activity. Strong activity initiated in the dorsal subnucleus, followed by activity in lateral and medial subnuclei. Whole-cell recordings from facial motoneurons showed weak respiratory drives, and electrical field potential recordings confirmed respiratory drive to particularly the dorsal and lateral subnuclei. Putative facial premotoneurons showed respiratory-related calcium signals, and were predominantly located dorsomedial to the facial nucleus. A novel motor activity on facial, cervical and thoracic nerves was synchronized with calcium signals at the ventromedial brainstem extending from the level of the facial nucleus to the medulla–spinal cord border. Cervical dorsal root stimulation induced similar ventromedial activity. The medial facial subnucleus showed calcium signals synchronized with this novel motor activity on cervical nerves, and cervical dorsal root stimulation induced similar medial facial subnucleus activity. In conclusion, the dorsal and lateral facial subnuclei are strongly respiratory-modulated, and the brainstem contains a novel pattern forming circuit that drives the medial facial subnucleus and cervical motor pools.

  17. Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area – an anterograde tract-tracing study

    Directory of Open Access Journals (Sweden)

    Rege Sugárka Papp

    2014-05-01

    Full Text Available The projections from the dorsolateral hypothalamic area (DLH to the lower brainstem have been investigated by using biotinylated dextran amine (BDA, an anterograde tracer in rats. The DLH can be divided into 3 areas (dorsomedial hypothalamus, perifornical area, lateral hypothalamic area, and further subdivided into 8 subdivisions. After unilateral stereotaxic injections of BDA into individual DLH subdivisions, the correct sites of injections were controlled histologically, and the distribution patterns of BDA-positive fibers were mapped on serial sections between the hypothalamus and spinal cord in 22 rats. BDA-labeled fibers were observable over 100 different brainstem areas, nuclei or subdivisions. Injections into the 8 DLH subdivisions established distinct topographical patterns. In general, the density of labeled fibers was low in the lower brainstem. High density of fibers was seen only 4 of the 116 areas: in the lateral and ventrolateral parts of the periaqueductal gray, the Barrington’s and the pedunculopontine tegmental nuclei. All of the biogenic amine cell groups in the lower brainstem (9 noradrenaline, 3 adrenaline and 9 serotonin cell groups received labeled fibers, some of them from all, or at least 7 DLH subdivisions, mainly from perifornical and ventral lateral hypothalamic neurons. Some of the tegmental nuclei and nuclei of the reticular formation were widely innervated, although the density of the BDA-labeled fibers was generally low. No definitive descending BDA-positive pathway, but long-run solitaire BDA-labeled fibers were seen in the lower brainstem. These descending fibers joined some of the large tracts or fasciculi in the brainstem. The distribution pattern of BDA-positive fibers of DLH origin throughout the lower brainstem was comparable to patterns of previously published orexin- or melanin-concentrating hormone-immunoreactive fibers with somewhat differences.

  18. Brainstem auditory evoked responses in healthy Argentine Mastiff dogs recorded with surface electrodes

    Directory of Open Access Journals (Sweden)

    M. Armașu

    2015-10-01

    Full Text Available RESUMOEvocado auditivo de respostas – BAER foi gravado utilizando eletrodos de superfície em sete cães Mastiff argentino saudáveis para estimulações monoaural e binaural em intensidades sonoras de 90 dB NPS . As latências e amplitudes das ondas I, III e V bem como os intervalos InterWave I- III , III -V e IV foram calculados. As diferenças estatísticas foram obtidas para as ondas III e latências V, amplitudes das ondas III e intervalos I- III e I-V entre mono e estimulação binaural. Por serem uma das raças geneticamente predispostas à surdez congênita, obtendo valores de referência BAER, os cães Mastiff argentino têm uma importância clínica especial.

  19. Control of vocal and respiratory patterns in birdsong: dissection of forebrain and brainstem mechanisms using temperature.

    Directory of Open Access Journals (Sweden)

    Aaron S Andalman

    Full Text Available Learned motor behaviors require descending forebrain control to be coordinated with midbrain and brainstem motor systems. In songbirds, such as the zebra finch, regular breathing is controlled by brainstem centers, but when the adult songbird begins to sing, its breathing becomes tightly coordinated with forebrain-controlled vocalizations. The periods of silence (gaps between song syllables are typically filled with brief breaths, allowing the bird to sing uninterrupted for many seconds. While substantial progress has been made in identifying the brain areas and pathways involved in vocal and respiratory control, it is not understood how respiratory and vocal control is coordinated by forebrain motor circuits. Here we combine a recently developed technique for localized brain cooling, together with recordings of thoracic air sac pressure, to examine the role of cortical premotor nucleus HVC (proper name in respiratory-vocal coordination. We found that HVC cooling, in addition to slowing all song timescales as previously reported, also increased the duration of expiratory pulses (EPs and inspiratory pulses (IPs. Expiratory pulses, like song syllables, were stretched uniformly by HVC cooling, but most inspiratory pulses exhibited non-uniform stretch of pressure waveform such that the majority of stretch occurred late in the IP. Indeed, some IPs appeared to change duration by the earlier or later truncation of an underlying inspiratory event. These findings are consistent with the idea that during singing the temporal structure of EPs is under the direct control of forebrain circuits, whereas that of IPs can be strongly influenced by circuits downstream of HVC, likely in the brainstem. An analysis of the temporal jitter of respiratory and vocal structure suggests that IPs may be initiated by HVC at the end of each syllable and terminated by HVC immediately before the onset of the next syllable.

  20. Erythropoietin and its receptors in the brainstem of adults with fatal falciparum malaria

    Directory of Open Access Journals (Sweden)

    White Nicholas J

    2009-11-01

    Full Text Available Abstract Background Facilitation of endogenous neuroprotective pathways, such as the erythropoietin (Epo pathway, has been proposed as adjuvant treatment strategies in cerebral malaria. Whether different endogenous protein expression levels of Epo or differences in the abundance of its receptor components could account for the extent of structural neuropathological changes or neurological complications in adults with severe malaria was investigated. Methods High sensitivity immunohistochemistry was used to assess the frequency, distribution and concordance of Epo and components of its homodimeric and heteromeric receptors, Epo receptor and CD131, within the brainstem of adults who died of severe malaria. The following relationships with Epo and its receptor components were also defined: (i sequestration and indicators of hypoxia; (ii vascular damage in the form of plasma protein leakage and haemorrhage; (iii clinical complications and neuropathological features of severe malaria disease. Brainstems of patients dying in the UK from unrelated non-infectious causes were examined for comparison. Results The incidence of endogenous Epo in parenchymal brain cells did not greatly differ between severe malaria and non-neurological UK controls at the time of death. However, EpoR and CD131 labelling of neurons was greater in severe malaria compared with non-neurological controls (P = .009. EpoR labelling of vessels was positively correlated with admission peripheral parasite count (P = .01 and cerebral sequestration (P P = .001. There were no significant correlations with indicators of vascular damage, neuronal chromatolysis, axonal swelling or vital organ failure. Conclusion Cells within the brainstem of severe malaria patients showed protein expression of Epo and its receptor components. However, the incidence of endogeneous expression did not reflect protection from vascular or neuronal injury, and/or clinical manifestations, such as coma. These

  1. Symptomatic cavernous malformations of the brainstem: functional outcome after microsurgical resection.

    Science.gov (United States)

    Schwartz, Christoph; Grillhösl, Andreas; Schichor, Christian; Suchorska, Bogdana; Romagna, Alexander; Tonn, Jörg-Christian; Zausinger, Stefan

    2013-11-01

    Brainstem cavernous malformations are associated with a considerable risk of hemorrhage and subsequent morbidity. This study provides a detailed work-up of clinical and radiological outcome as well as identification of prognostic factors in patients who had suffered from symptomatic hemorrhages. Patients who had undergone surgery of symptomatic BSCMs were evaluated pre- and postoperatively both neurologically and neuroradiologically supplemented by telephone interviews. Additionally, patients were scored according to the Scandinavian Stroke Scale. Multiple uni- and multivariate analyses of possible clinical and radiological prognostic factors were conducted. The study population comprised 35 patients. Mean age at operation was 39.3 ± 13.0 years with microsurgical resection of a total of 37 different BSCMs between 2002 and 2011. Median clinical follow-up was 44.0 months (range 8-116 months). Postoperative MRI showed eventually complete resection of all BSCMs. Postoperative overall outcome revealed complete resolution of neurological symptoms for 5/35 patients, 14/35 improved and 9/35 remained unchanged. 7/35 suffered from a postoperative new and permanent neurological deficit, mostly affecting the facial nerve or hemipareses with mild impairment. Pre- and postoperative Scandinavian Stroke Scale scores were 11.0 ± 2.4 and 11.4 ± 2.2 (p = 0.55). None of the analyzed factors were found to significantly correlate with patients' clinical outcome. Complete resection of brainstem cavernous malformations can be achieved with an acceptable risk for long-term morbidity and surgery-related new deficits (~20 %). Neurological outcome is mainly determined within the first 6 months after surgery. Surgical treatment of brainstem cavernous malformations is recommended in symptomatic patients, in whom the lesion is accessible for surgery.

  2. Migration of a sewing needle foreign body into the brainstem of a cat.

    Science.gov (United States)

    Cottam, Emily J; Gannon, Kristi

    2015-01-01

    A 1-year-old, female spayed domestic shorthair cat with a 6 week history of upper respiratory signs and a progressive reluctance to move, which culminated in a right-sided hemiparesis, was found to have a sewing needle foreign body lodged in the brainstem. Surgical extraction of the needle was successful and the cat's neurological deficits resolved over the days to weeks following its removal. This case report describes, to our knowledge, the first reported incidence and management of an ingested sewing needle migrating into the central nervous system of a cat.

  3. Neuroimaging of Infectious and Inflammatory Diseases of the Pediatric Cerebellum and Brainstem.

    Science.gov (United States)

    Rossi, Andrea; Martinetti, Carola; Morana, Giovanni; Severino, Mariasavina; Tortora, Domenico

    2016-08-01

    Cerebellar involvement by infectious-inflammatory conditions is rare in children. Most patients present with acute ataxia, and are typically previously healthy, young (often preschool) children. Viral involvement is the most common cause and ranges from acute postinfectious ataxia to acute cerebellitis MR imaging plays a crucial role in the evaluation of patients suspected of harboring inflammatory-infectious involvement of the cerebellum and brainstem. Knowledge of the imaging features of these disorders and technical competence on pediatric MR imaging are necessary for a correct interpretation of findings, which in turn prompts further management. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Increased astrocytic expression of metallothioneins I + II in brainstem of adult rats treated with 6-aminonicotinamide

    DEFF Research Database (Denmark)

    Penkowa, Milena; Hidalgo, Juan; Moos, Torben

    1997-01-01

    The cerebral distribution of metallothioneins I and II (MT-I + II) was studied in adult rats subjected to i.p. injection with the gliotoxin 6-aminonicotinamide (6-AN). Grey matter regions of the brainstem heralded numerous OX-42-positive macrophages and microglia, indicating that 6-AN primarily...... caused damage to this part of the brain. In the grey matter regions infiltrated with OX-42-positive cells, astrocytes identified by anti-GFAP and MT-I + II antibodies were almost absent. By contrast, in the peripheral zone of the lesioned regions numerous reactive GFAP- and MT-I + II-positive astrocytes...

  5. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura.

    Science.gov (United States)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E; Younis, Samaira; Wolfram, Frauke; Cramer, Stig P; Larsson, Henrik B W; Ashina, Messoud

    2017-06-01

    See Moskowitz (doi:10.1093/brain/awx099) for a scientific commentary on this article.The migraine aura is characterized by transient focal cortical disturbances causing dramatic neurological symptoms that are usually followed by migraine headache. It is currently not understood how the aura symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas of the anterior, middle and posterior circulation during spontaneous attacks of migraine with aura. Patients reported to our institution to undergo magnetic resonance imaging during the headache phase after presenting with typical visual aura. Nineteen patients were scanned during attacks and on an attack-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability in any of the investigated regions. There was no correlation between blood-brain barrier permeability, brain perfusion, and time from symptom onset to examination or pain intensity. Our findings demonstrate hyperperfusion in brainstem during the headache phase of migraine with aura, while the blood-brain barrier remains intact during attacks of migraine with aura. These data thus contradict the preclinical hypothesis of cortical spreading depression-induced blood-brain barrier

  6. A rare case of acute poster ior reversible encephalopathy syndrome involving brainstem in a child

    Directory of Open Access Journals (Sweden)

    Olfa Chakroun-Walha

    2016-11-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a rare entity involving brainstem in very rare reported cases. We describe here the case of a boy who presented to the emergency department for headaches and strabismus. Diagnosis of PRES was retained by magnetic resonance imaging. The causes were blood pressure urgency and renal failure. Location of lesions was very rarely reported in literature and neurological troubles were persistent. Emergency physicians should evocate PRES each time there is a clinical context associated with neurological troubles by a normal brain CT scan. Early diagnosis is very important to treat its causes and improve prognosis.

  7. Visual cortical somatosensory and brainstem auditory evoked potentials following incidental irradiation of the rhombencephalon

    Energy Technology Data Exchange (ETDEWEB)

    Nightingale, S. (Royal Victoria Infirmary, Newcastle upon Tyne (UK)); Schofield, I.S.; Dawes, P.J.D.K. (Newcastle upon Tyne Univ. (UK). Newcastle General Hospital)

    1984-01-01

    Visual, cortical somatosensory and brainstem auditory evoked potentials were recorded before incidental irradiation of the rhombencephalon during radiotherapy in and around the middle ear, and at 11 weeks and eight months after completion of treatment. No patient experienced neurological symptoms during this period. No consistent changes in evoked potentials were found. The failure to demonstrate subclinical radiation-induced demyelination suggests either that the syndrome of early-delayed radiation rhombencephalopathy occurs in an idiosyncratic manner, or that any subclinical lesions are not detectable by serial evoked potential recordings.

  8. Visual cortical somatosensory and brainstem auditory evoked potentials following incidental irradiation of the rhombencephalon

    International Nuclear Information System (INIS)

    Nightingale, S.; Schofield, I.S.; Dawes, P.J.D.K.

    1984-01-01

    Visual, cortical somatosensory and brainstem auditory evoked potentials were recorded before incidental irradiation of the rhombencephalon during radiotherapy in and around the middle ear, and at 11 weeks and eight months after completion of treatment. No patient experienced neurological symptoms during this period. No consistent changes in evoked potentials were found. The failure to demonstrate subclinical radiation-induced demyelination suggests either that the syndrome of early-delayed radiation rhombencephalopathy occurs in an idiosyncratic manner, or that any subclinical lesions are not detectable by serial evoked potential recordings. (author)

  9. Factors Associated With Neurological Recovery of Brainstem Function Following Postoperative Conformal Radiation Therapy for Infratentorial Ependymoma

    International Nuclear Information System (INIS)

    Merchant, Thomas E.; Chitti, Ramana M.; Li Chenghong; Xiong Xiaoping; Sanford, Robert A.; Khan, Raja B.

    2010-01-01

    Purpose: To identify risk factors associated with incomplete neurological recovery in pediatric patients with infratentorial ependymoma treated with postoperative conformal radiation therapy (CRT). Methods: The study included 68 patients (median age ± standard deviation of 2.6 ± 3.8 years) who were followed for 5 years after receiving CRT (54-59.4 Gy) and were assessed for function of cranial nerves V to VII and IX to XII, motor weakness, and dysmetria. The mean (± standard deviation) brainstem dose was 5,487 (±464) cGy. Patients were divided into four groups representing those with normal baseline and follow-up, those with abnormal baseline and full recovery, those with abnormal baseline and partial or no recovery, and those with progressive deficits at 12 (n = 62 patients), 24 (n = 57 patients), and 60 (n = 50 patients) months. Grouping was correlated with clinical and treatment factors. Results: Risk factors (overall risk [OR], p value) associated with incomplete recovery included gender (male vs. female, OR = 3.97, p = 0.036) and gross tumor volume (GTV) (OR/ml = 1.23, p = 0.005) at 12 months, the number of resections (>1 vs. 1; OR = 23.7, p = 0.003) and patient age (OR/year = 0.77, p = 0.029) at 24 months, and cerebrospinal fluid (CSF) shunting (Yes vs. No; OR = 21.9, p = 0.001) and GTV volume (OR/ml = 1.18, p = 0.008) at 60 months. An increase in GTV correlated with an increase in the number of resections (p = 0.001) and CSF shunting (p = 0.035); the number of resections correlated with CSF shunting (p < 0.0001), and male patients were more likely to undergo multiple tumor resections (p = 0.003). Age correlated with brainstem volume (p < 0.0001). There were no differences in outcome based on the absolute or relative volume of the brainstem that received more than 54 Gy. Conclusions: Incomplete recovery of brainstem function after CRT for infratentorial ependymoma is related to surgical morbidity and the volume and the extent of tumor.

  10. The cormorant ear – an adaptation to underwater hearing?

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Wahlberg, Magnus; Christensen-Dalsgaard, Jakob

    anatomy. Wild-caught fledglings were anesthetized and their auditory brainstem response (ABR) to clicks and tone bursts was measured, first in an anechoic box in air and then in a large water-filled tank with their head and neck submerged 10 cm below the surface. The overall shape of air audiograms...... piston, which is reminiscent of the turtle ear....

  11. Auditory screening in infants for early detection of permanent ...

    African Journals Online (AJOL)

    In infants referred at this stage, an auditory brainstem response (ABR) test was the next investigation. Data analyzed using Statistical Package for the Social Sciences software Version 16 (Chicago, IL, USA, 16) through descriptive statistic method. Results: In the first screening stage, 10.8% (1648/15165) cases were referred ...

  12. Auditory and audio-visual processing in patients with cochlear, auditory brainstem, and auditory midbrain implants: An EEG study.

    Science.gov (United States)

    Schierholz, Irina; Finke, Mareike; Kral, Andrej; Büchner, Andreas; Rach, Stefan; Lenarz, Thomas; Dengler, Reinhard; Sandmann, Pascale

    2017-04-01

    There is substantial variability in speech recognition ability across patients with cochlear implants (CIs), auditory brainstem implants (ABIs), and auditory midbrain implants (AMIs). To better understand how this variability is related to central processing differences, the current electroencephalography (EEG) study compared hearing abilities and auditory-cortex activation in patients with electrical stimulation at different sites of the auditory pathway. Three different groups of patients with auditory implants (Hannover Medical School; ABI: n = 6, CI: n = 6; AMI: n = 2) performed a speeded response task and a speech recognition test with auditory, visual, and audio-visual stimuli. Behavioral performance and cortical processing of auditory and audio-visual stimuli were compared between groups. ABI and AMI patients showed prolonged response times on auditory and audio-visual stimuli compared with NH listeners and CI patients. This was confirmed by prolonged N1 latencies and reduced N1 amplitudes in ABI and AMI patients. However, patients with central auditory implants showed a remarkable gain in performance when visual and auditory input was combined, in both speech and non-speech conditions, which was reflected by a strong visual modulation of auditory-cortex activation in these individuals. In sum, the results suggest that the behavioral improvement for audio-visual conditions in central auditory implant patients is based on enhanced audio-visual interactions in the auditory cortex. Their findings may provide important implications for the optimization of electrical stimulation and rehabilitation strategies in patients with central auditory prostheses. Hum Brain Mapp 38:2206-2225, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. SU-F-T-206: Proton Treatment Techniques for Posterior Fossa Tumors: Consequences for LET and Dose/Volume Parameters for the Brainstem and Organs at Risk

    Energy Technology Data Exchange (ETDEWEB)

    Giantsoudi, D; Adams, J; MacDonald, S; Paganetti, H [Massachusetts General Hospital, Boston, MA (United States)

    2016-06-15

    Purpose: In proton radiation therapy of posterior fossa tumors, to spare other sensitive structures, the preferred beam geometry results in placing the treatment field distal edge within or just beyond the brainstem, including in at least partially in the treatment volume. Concerns for brainstem toxicity are increased and a controversy exists as to weather the beam’s distal edge should be placed within the brainstem or beyond it, to avoid elevated linear energy transfer (LET) and relative biological effectiveness (RBE) within the brainstem. The dosimetric efficacy of these techniques was examined, accounting for LET- and dose-dependent variable RBE distributions. Methods: Three treatment planning techniques were applied in six ependymoma cases: (a) three-field dose-sparing, with beams’ distal edge within the brainstem; (b) three-field LET-sparing, using same beam directions as (a) but extended field ranges beyond the brainstem; (c) two-posterior-oblique LET-sparing, with extended ranges as (b). Monte Carlo calculated dose, LET and RBE-weighted dose distributions were compared. Results: Lower LET values in the brainstem were accompanied by higher median dose: 53.7 Gy[RBE] and 54.3 Gy[RBE] for techniques (b) and (c) versus 52.1 Gy[RBE] for (a). Accounting for variable RBE, a 15% increase of the brainstem volume receiving at least 60 Gy[RBE] was observed for technique (c) versus (a). Maximum variable-RBE-weighted brainstem dose was comparable for all techniques. Conclusion: Extending the treatment beam range beyond the brainstem, significantly increased its volume receiving high dose radiation, even when accounting for the decreased LET values. The dosimetric benefits of techniques limiting the brainstem dose may outweigh the impact of LET reduction achieved through this technique, especially since clinical consequences of increased LET at the end of range have not been proven yet.

  14. Production of bioenergy in anaerobic baffled reactor (ABR) and sludge blanket (UASB) in the treatment os swine waste water; Producao de bioenergia em reatores anaerobios compartimentado (RAC) e de manta de lodo (UASB) no tratamento de efluentes de suinocultura

    Energy Technology Data Exchange (ETDEWEB)

    Moterani, Fabricio; Pereira, Erlon Lopes; Campos, Claudio M.M. [Universidade Federal de Lavras (DEG/UFLA), MG (Brazil). Dept. de Engenharia], email: fabricio_moterani@yahoo.com.br

    2011-07-01

    The biogas is obtained in the processes of degradation of organic matter by the action of bacterial consortium in the environment. The aim of this study was to evaluate the biogas production in anaerobic UASB and ABR in swine wastewater treatment. For this we used the theoretical estimated and actual production of biogas measured by anaerobic gasometers installed in the units. Methane was determined by gas chromatography (GC) and its theoretical output was 66 LCH4 kgSVT d{sup -1} and 11.9 LCH4 kgSVT d{sup -1} and 24.7 m{sup 3} d{sup -1} and 5.4 m{sup 3} d{sup -1} to ABR and UASB, respectively. Regarding the actual production of biogas in the reactor provided by the gas tank, found the values of 1,166.4 m{sup 3}; 0.1 m{sup 3}; 27.4 m{sup 3} and 12,598.5 m{sup 3} of biogas for compartments 1, 2 and 3 and ABR for the UASB reactor, respectively, totaling, production of 13,792.4 m{sup 3} in the units together, with an average of 113 m{sup 3} of biogas per day. But, it concludes with this research that the use of effluent from produce energy through biogas in swine farming is effective, which can be used in rural productive system itself. (author)

  15. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold and heat

    Directory of Open Access Journals (Sweden)

    Kazuo eNakashima

    2014-05-01

    Full Text Available Drought negatively impacts plant growth and the productivity of crops around the world. Understanding the molecular mechanisms in the drought response is important for improvement of drought tolerance using molecular techniques. In plants, abscisic acid (ABA is accumulated under osmotic stress conditions caused by drought, and has a key role in stress responses and tolerance. Comprehensive molecular analyses have shown that ABA regulates the expression of many genes under osmotic stress conditions, and the ABA-responsive element (ABRE is the major cis-element for ABA-responsive gene expression. Transcription factors (TFs are master regulators of gene expression. ABRE-binding protein (AREB and ABRE-binding factor (ABF TFs control gene expression in an ABA-dependent manner. SNF1-related protein kinases 2, group A 2C-type protein phosphatases, and ABA receptors were shown to control the ABA signaling pathway. ABA-independent signaling pathways such as dehydration-responsive element-binding protein (DREB TFs and NAC TFs are also involved in stress responses including drought, heat and cold. Recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress responses. The important roles of these transcription factors in crosstalk among abiotic stress responses will be discussed. Control of ABA or stress signaling factor expression can improve tolerance to environmental stresses. Recent studies using crops have shown that stress-specific overexpression of TFs improves drought tolerance and grain yield compared with controls in the field.

  16. Novel Anterior Brainstem Magnetic Resonance Imaging Findings in Non-Small Cell Lung Cancer with Leptomeningeal Carcinomatosis

    Directory of Open Access Journals (Sweden)

    Chun-Yu Cheng

    2017-10-01

    Full Text Available Leptomeningeal carcinomatosis (LC is found in around 4% of patients with non-small cell lung cancer (NSCLC. The most common radiological finding of LC is diffuse leptomeningeal enhancement on contrast-enhanced brain magnetic resonance imaging (MRI. Herein, we report a novel brain MRI finding—non-enhanced, band-like, symmetric restricted diffusion along the anterior surface of the brainstem—of LC in four patients with NSCLC. We also identified three additional cases with similar MRI findings in a literature review. We hypothesized that the restricted diffusion along the anterior brainstem was caused by malignant cells concentrating in the cistern around the brainstem and infiltrating into the circumferential perforating arteries along the anterior brainstem surface, which then resulted in microinfarctions.

  17. Respiratory neuron characterization reveals intrinsic bursting properties in isolated adult turtle brainstems (Trachemys scripta).

    Science.gov (United States)

    Johnson, Stephen M; Hedrick, Michael S; Krause, Bryan M; Nilles, Jacob P; Chapman, Mark A

    2016-04-01

    It is not known whether respiratory neurons with intrinsic bursting properties exist within ectothermic vertebrate respiratory control systems. Thus, isolated adult turtle brainstems spontaneously producing respiratory motor output were used to identify and classify respiratory neurons based on their firing pattern relative to hypoglossal (XII) nerve activity. Most respiratory neurons (183/212) had peak activity during the expiratory phase, while inspiratory, post-inspiratory, and novel pre-expiratory neurons were less common. During synaptic blockade conditions, ∼10% of respiratory neurons fired bursts of action potentials, with post-inspiratory cells (6/9) having the highest percentage of intrinsic burst properties. Most intrinsically bursting respiratory neurons were clustered at the level of the vagus (X) nerve root. Synaptic inhibition blockade caused seizure-like activity throughout the turtle brainstem, which shows that the turtle respiratory control system is not transformed into a network driven by intrinsic