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

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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.

Auditory brainstem activity and development evoked by apical versus basal cochlear implant electrode stimulation in children.

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Gordon, K A; Papsin, B C; Harrison, R V

2007-08-01

The role of apical versus basal cochlear implant electrode stimulation on central auditory development was examined. We hypothesized that, in children with early onset deafness, auditory development evoked by basal electrode stimulation would differ from that evoked more apically. Responses of the auditory nerve and brainstem, evoked by an apical and a basal implant electrode, were measured over the first year of cochlear implant use in 50 children with early onset severe to profound deafness who used hearing aids prior to implantation. Responses at initial stimulation were of larger amplitude and shorter latency when evoked by the apical electrode. No significant effects of residual hearing or age were found on initial response amplitudes or latencies. With implant use, responses evoked by both electrodes showed decreases in wave and interwave latencies reflecting decreased neural conduction time through the brainstem. Apical versus basal differences persisted with implant experience with one exception; eIII-eV interlatency differences decreased with implant use. Acute stimulation shows prolongation of basally versus apically evoked auditory nerve and brainstem responses in children with severe to profound deafness. Interwave latencies reflecting neural conduction along the caudal and rostral portions of the brainstem decreased over the first year of implant use. Differences in neural conduction times evoked by apical versus basal electrode stimulation persisted in the caudal but not rostral brainstem. Activity-dependent changes of the auditory brainstem occur in response to both apical and basal cochlear implant electrode stimulation.

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

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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 fibr...

Effect of Infant Prematurity on Auditory Brainstem Response at Preschool Age

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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

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

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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.  

The absence of later wave components in auditory brainstem responses as an initial manifestation of type 2 Gaucher disease.

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Okubo, Yusuke; Goto, Masahiro; Sakakibara, Hiroshi; Terakawa, Toshiro; Kaneko, Takashi; Miyama, Sahoko

2014-12-01

Type 2 Gaucher disease is the most severe neuronopathic form of Gaucher disease and is characterized by severe neurodegeneration with brainstem involvement and organ failure. Prediction or diagnosis of type 2 Gaucher disease before the development of neurological complications is difficult. A 5-month-old female infant presented with deafness without other neurological abnormalities. Auditory brainstem response analysis revealed the absence of later wave components. Two months later, muscular rigidity became evident, followed by the development of opisthotonus and strabismus. Rapid progression of splenomegaly led to the diagnosis of type 2 Gaucher disease. Abnormal auditory brainstem response findings may already exist before the development of severe brainstem abnormalities such as muscular rigidity and opisthotonus in type 2 Gaucher disease. When patients present with deafness and absent later wave components on auditory brainstem response, type 2 Gaucher disease should be included in the differential diagnosis even in the absence of other neurological abnormalities. Copyright © 2014 Elsevier Inc. All rights reserved.

Brainstem auditory evoked potentials in healthy cats recorded with surface electrodes

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Mihai Musteata

2013-01-01

Full Text Available The aim of this study was to evaluate the brainstem auditory evoked potentials of seven healthy cats, using surface electrodes. Latencies of waves I, III and V, and intervals I–III, I–V and III–V were recorded. Monaural and binaural stimulation of the cats were done with sounds ranging between 40 and 90 decibel Sound Pressure Level. All latencies were lower than those described in previous studies, where needle electrodes were used. In the case of binaural stimulation, latencies of waves III and V were greater compared to those obtained for monaural stimulation (P P > 0.05. Regardless of the sound intensity, the interwave latency was constant (P > 0.05. Interestingly, no differences were noticed for latencies of waves III and V when sound intensity was higher than 80dB SPL. This study completes the knowledge in the field of electrophysiology and shows that the brainstem auditory evoked potentials in cats using surface electrodes is a viable method to record the transmission of auditory information. That can be faithfully used in clinical practice, when small changes of latency values may be an objective factor in health status evaluation.

Comparison between chloral hydrate and propofol-ketamine as sedation regimens for pediatric auditory brainstem response testing.

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Abulebda, Kamal; Patel, Vinit J; Ahmed, Sheikh S; Tori, Alvaro J; Lutfi, Riad; Abu-Sultaneh, Samer

2017-10-28

The use of diagnostic auditory brainstem response testing under sedation is currently the "gold standard" in infants and young children who are not developmentally capable of completing the test. The aim of the study is to compare a propofol-ketamine regimen to an oral chloral hydrate regimen for sedating children undergoing auditory brainstem response testing. Patients between 4 months and 6 years who required sedation for auditory brainstem response testing were included in this retrospective study. Drugs doses, adverse effects, sedation times, and the effectiveness of the sedative regimens were reviewed. 73 patients underwent oral chloral hydrate sedation, while 117 received propofol-ketamine sedation. 12% of the patients in the chloral hydrate group failed to achieve desired sedation level. The average procedure, recovery and total nursing times were significantly lower in the propofol-ketamine group. Propofol-ketamine group experienced higher incidence of transient hypoxemia. Both sedation regimens can be successfully used for sedating children undergoing auditory brainstem response testing. While deep sedation using propofol-ketamine regimen offers more efficiency than moderate sedation using chloral hydrate, it does carry a higher incidence of transient hypoxemia, which warrants the use of a highly skilled team trained in pediatric cardio-respiratory monitoring and airway management. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

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

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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.

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

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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.

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

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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.

Auditory and audio-visual processing in patients with cochlear, auditory brainstem, and auditory midbrain implants: An EEG study.

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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.

[Forensic application of brainstem auditory evoked potential in patients with brain concussion].

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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.

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

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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.

Brainstem auditory evoked potential testing in Dalmatian dogs in Brazil

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M.I.P. Palumbo

2014-04-01

Full Text Available The brain stem auditory-evoked potential (BAEP is an electrophysiologic test that detects and records the electrical activity in the auditory system from cochlea to midbrain, generated after an acoustic stimulus applied to the external ear. The aim of this study is to obtain normative data for BAEP in Dalmatian dogs in order to apply this to the evaluation of deafness and other neurologic disorders. BAEP were recorded from 30 Dalmatian dogs for a normative Brazilian study. Mean latencies for waves I, III, and V were 1.14 (±0.09, 2.62 (±0.10, and 3.46 (±0.14 ms, respectively. Mean inter-peak latencies for I-III, III-V, and I-V intervals were 1.48 (±0.17, 0.84 (±0.12, and 2.31 (±0.18 ms, respectively. Unilateral abnormalities were found in 16.7% of animals and bilateral deafness was seen in one dog. The normative data obtained in this paper is compatible with other published data. As far as we know this is the first report of deafness occurrence in Dalmatian dogs in Brazil.

Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

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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.

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

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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

Attention-related modulation of auditory brainstem responses during contralateral noise exposure.

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Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

2008-10-29

As determinants facilitating attention-related modulation of the auditory brainstem response (ABR), two experimental factors were examined: (i) auditory discrimination; and (ii) contralateral masking intensity. Tone pips at 80 dB sound pressure level were presented to the left ear via either single-tone exposures or oddball exposures, whereas white noise was delivered continuously to the right ear at variable intensities (none--80 dB sound pressure level). Participants each conducted two tasks during stimulation, either reading a book (ignoring task) or detecting target tones (attentive task). Task-related modulation within the ABR range was found only during oddball exposures at contralateral masking intensities greater than or equal to 60 dB. Attention-related modulation of ABR can thus be detected reliably during auditory discrimination under contralateral masking of sufficient intensity.

Concentrated pitch discrimination modulates auditory brainstem responses during contralateral noise exposure.

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Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

2010-03-31

This study examined a notion that auditory discrimination is a requisite for attention-related modulation of the auditory brainstem response (ABR) during contralateral noise exposure. Given that the right ear was exposed continuously with white noise at an intensity of 60-80 dB sound pressure level, tone pips at 80 dB sound pressure level were delivered to the left ear through either single-stimulus or oddball procedures. Participants conducted reading (ignoring task) and counting target tones (attentive task) during stimulation. The oddball but not the single-stimulus procedures elicited task-related modulations in both early (ABR) and late (processing negativity) event-related potentials simultaneously. The elicitation of the attention-related ABR modulation during contralateral noise exposure is thus considered to require auditory discrimination and have the corticofugal nature evidently.

Astrocyte-secreted factors modulate a gradient of primary dendritic arbors in nucleus laminaris of the avian auditory brainstem.

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Matthew J Korn

Full Text Available Neurons in nucleus laminaris (NL receive binaural, tonotopically matched input from nucleus magnocelluaris (NM onto bitufted dendrites that display a gradient of dendritic arbor size. These features improve computation of interaural time differences, which are used to determine the locations of sound sources. The dendritic gradient emerges following a period of significant reorganization at embryonic day 15 (E15, which coincides with the emergence of astrocytes that express glial fibrillary acidic protein (GFAP in the auditory brainstem. The major changes include a loss of total dendritic length, a systematic loss of primary dendrites along the tonotopic axis, and lengthening of primary dendrites on caudolateral NL neurons. Here we have tested whether astrocyte-derived molecules contribute to these changes in dendritic morphology. We used an organotypic brainstem slice preparation to perform repeated imaging of individual dye-filled NL neurons to determine the effects of astrocyte-conditioned medium (ACM on dendritic morphology. We found that treatment with ACM induced a decrease in the number of primary dendrites in a tonotopically graded manner similar to that observed during normal development. Our data introduce a new interaction between astrocytes and neurons in the auditory brainstem and suggest that these astrocytes influence multiple aspects of auditory brainstem maturation.

Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei.

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Tang, Yezhong; Christensen-Dalsgaard, Jakob; Carr, Catherine E

2012-06-01

We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of low to middle best-frequency fibers that bifurcate to project to both the NA and the nucleus magnocellularis (NM). The projection to NM formed large somatic terminals and bouton terminals. NM projected bilaterally to the second-order nucleus laminaris (NL), such that the ipsilateral projection innervated the dorsal NL neuropil, whereas the contralateral projection crossed the midline and innervated the ventral dendrites of NL neurons. Neurons in NL were generally bitufted, with dorsoventrally oriented dendrites. NL projected to the contralateral torus semicircularis and to the contralateral ventral superior olive (SOv). NA projected to ipsilateral dorsal superior olive (SOd), sent a major projection to the contralateral SOv, and projected to torus semicircularis. The SOd projected to the contralateral SOv, which projected back to the ipsilateral NM, NL, and NA. These results suggest homologous patterns of auditory connections in lizards and archosaurs but also different processing of low- and high-frequency information in the brainstem. Copyright © 2011 Wiley Periodicals, Inc.

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

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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.

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

Rapid measurement of auditory filter shape in mice using the auditory brainstem response and notched noise.

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Lina, Ioan A; Lauer, Amanda M

2013-04-01

The notched noise method is an effective procedure for measuring frequency resolution and auditory filter shapes in both human and animal models of hearing. Briefly, auditory filter shape and bandwidth estimates are derived from masked thresholds for tones presented in noise containing widening spectral notches. As the spectral notch widens, increasingly less of the noise falls within the auditory filter and the tone becomes more detectible until the notch width exceeds the filter bandwidth. Behavioral procedures have been used for the derivation of notched noise auditory filter shapes in mice; however, the time and effort needed to train and test animals on these tasks renders a constraint on the widespread application of this testing method. As an alternative procedure, we combined relatively non-invasive auditory brainstem response (ABR) measurements and the notched noise method to estimate auditory filters in normal-hearing mice at center frequencies of 8, 11.2, and 16 kHz. A complete set of simultaneous masked thresholds for a particular tone frequency were obtained in about an hour. ABR-derived filter bandwidths broadened with increasing frequency, consistent with previous studies. The ABR notched noise procedure provides a fast alternative to estimating frequency selectivity in mice that is well-suited to high through-put or time-sensitive screening. Copyright © 2013 Elsevier B.V. All rights reserved.

Auditory Brainstem Response to Complex Sounds Predicts Self-Reported Speech-in-Noise Performance

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Anderson, Samira; Parbery-Clark, Alexandra; White-Schwoch, Travis; Kraus, Nina

2013-01-01

Purpose: To compare the ability of the auditory brainstem response to complex sounds (cABR) to predict subjective ratings of speech understanding in noise on the Speech, Spatial, and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004) relative to the predictive ability of the Quick Speech-in-Noise test (QuickSIN; Killion, Niquette,…

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.

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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

Effects of myelin or cell body brainstem lesions on 3-channel Lissajous' trajectories of feline auditory brainstem evoked potentials

OpenAIRE

Pratt, H; Zaaroor, M; Bleich, N; Starr, A

1991-01-01

Auditory brainstem evoked potentials (ABEP) were recorded from 16 awake cats to obtain 3-Channel Lissajous' Trajectories (3CLTs) using three orthogonal differential electrode configurations (nasion - midline nuchal ridge, left - right mastoids, vertex - midline under the mandible). Potentials, evoked by monaural 80 dBnHL (re. human threshold) clicks, were studied before, and up to 7 weeks after inducing neuronal lesions localized to the cochlear nucleus (CN) or the superior olivary complex (S...

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

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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

The Physiological Basis and Clinical Use of the Binaural Interaction Component of the Auditory Brainstem Response

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Klump, Georg M.; Tollin, Daniel J.

2016-01-01

The auditory brainstem response (ABR) is a sound-evoked non-invasively measured electrical potential representing the sum of neuronal activity in the auditory brainstem and midbrain. ABR peak amplitudes and latencies are widely used in human and animal auditory research and for clinical screening. The binaural interaction component (BIC) of the ABR stands for the difference between the sum of the monaural ABRs and the ABR obtained with binaural stimulation. The BIC comprises a series of distinct waves, the largest of which (DN1) has been used for evaluating binaural hearing in both normal hearing and hearing-impaired listeners. Based on data from animal and human studies, we discuss the possible anatomical and physiological bases of the BIC (DN1 in particular). The effects of electrode placement and stimulus characteristics on the binaurally evoked ABR are evaluated. We review how inter-aural time and intensity differences affect the BIC and, analyzing these dependencies, draw conclusion about the mechanism underlying the generation of the BIC. Finally, the utility of the BIC for clinical diagnoses are summarized. PMID:27232077

Structural Changes and Lack of HCN1 Channels in the Binaural Auditory Brainstem of the Naked Mole-Rat (Heterocephalus glaber).

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Gessele, Nikodemus; Garcia-Pino, Elisabet; Omerbašić, Damir; Park, Thomas J; Koch, Ursula

2016-01-01

Naked mole-rats (Heterocephalus glaber) live in large eu-social, underground colonies in narrow burrows and are exposed to a large repertoire of communication signals but negligible binaural sound localization cues, such as interaural time and intensity differences. We therefore asked whether monaural and binaural auditory brainstem nuclei in the naked mole-rat are differentially adjusted to this acoustic environment. Using antibody stainings against excitatory and inhibitory presynaptic structures, namely the vesicular glutamate transporter VGluT1 and the glycine transporter GlyT2 we identified all major auditory brainstem nuclei except the superior paraolivary nucleus in these animals. Naked mole-rats possess a well structured medial superior olive, with a similar synaptic arrangement to interaural-time-difference encoding animals. The neighboring lateral superior olive, which analyzes interaural intensity differences, is large and elongated, whereas the medial nucleus of the trapezoid body, which provides the contralateral inhibitory input to these binaural nuclei, is reduced in size. In contrast, the cochlear nucleus, the nuclei of the lateral lemniscus and the inferior colliculus are not considerably different when compared to other rodent species. Most interestingly, binaural auditory brainstem nuclei lack the membrane-bound hyperpolarization-activated channel HCN1, a voltage-gated ion channel that greatly contributes to the fast integration times in binaural nuclei of the superior olivary complex in other species. This suggests substantially lengthened membrane time constants and thus prolonged temporal integration of inputs in binaural auditory brainstem neurons and might be linked to the severely degenerated sound localization abilities in these animals.

Structural Changes and Lack of HCN1 Channels in the Binaural Auditory Brainstem of the Naked Mole-Rat (Heterocephalus glaber.

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Nikodemus Gessele

Full Text Available Naked mole-rats (Heterocephalus glaber live in large eu-social, underground colonies in narrow burrows and are exposed to a large repertoire of communication signals but negligible binaural sound localization cues, such as interaural time and intensity differences. We therefore asked whether monaural and binaural auditory brainstem nuclei in the naked mole-rat are differentially adjusted to this acoustic environment. Using antibody stainings against excitatory and inhibitory presynaptic structures, namely the vesicular glutamate transporter VGluT1 and the glycine transporter GlyT2 we identified all major auditory brainstem nuclei except the superior paraolivary nucleus in these animals. Naked mole-rats possess a well structured medial superior olive, with a similar synaptic arrangement to interaural-time-difference encoding animals. The neighboring lateral superior olive, which analyzes interaural intensity differences, is large and elongated, whereas the medial nucleus of the trapezoid body, which provides the contralateral inhibitory input to these binaural nuclei, is reduced in size. In contrast, the cochlear nucleus, the nuclei of the lateral lemniscus and the inferior colliculus are not considerably different when compared to other rodent species. Most interestingly, binaural auditory brainstem nuclei lack the membrane-bound hyperpolarization-activated channel HCN1, a voltage-gated ion channel that greatly contributes to the fast integration times in binaural nuclei of the superior olivary complex in other species. This suggests substantially lengthened membrane time constants and thus prolonged temporal integration of inputs in binaural auditory brainstem neurons and might be linked to the severely degenerated sound localization abilities in these animals.

Study of the correlation of brainstem auditory evoked potentials and magnetic resonance imaging in children with spastic cerebral palsy

International Nuclear Information System (INIS)

Fobe, Lisete Pessoa de Oliveira

1999-01-01

Central auditory evaluation in 21 children with cerebral palsy was done with brainstem auditory evoked potentials (BAEP) and correlated with brain magnetic resonance imaging findings (MRI); 12 boys and 9 girls between 5 and 12 years old were studied. All children had follow-up at the Institute of Orthopedics and Traumatology of Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The control group was done with 17 children, 10 boys and 7 girls (mean age 8.06 years, SD 2.27 years). The BAEP abnormalities were: decrease of latency of wave V; decrease of latency III-V and I-IV intervals at the right side. All patients has MRI supratentorial abnormalities and 11 had brainstem atrophy. The MRI pathologic findings were: ventricular enlargement (n=17 or 80.95%), cortical/subcortical atrophy (n=15 or 71.42%), left brainstem atrophy (n=11 or 52.38%), periventricular leukomalacia (n=10 or 47.61%), infarction in the left middle cerebral artery territory (n=6 or 28.57%), and malformations such as schizencephaly and colpocephaly (n=5 or 23.80%). The findings of the decrease latencies in children with cerebral palsy suggest the contribution of decussating auditory fibers at the lower and upper pons and midbrain, the lack of homogeneity of the surrounding volume of the conductor fibres and the presence of several concurrently active potential generators sources, should be facilitating mechanisms for the nervous input to brainstem. (author)

Study of the correlation of brainstem auditory evoked potentials and magnetic resonance imaging in children with spastic cerebral palsy

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Fobe, Lisete Pessoa de Oliveira [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina]. E-mail: lispessoa@yahoo.com

1999-12-01

Central auditory evaluation in 21 children with cerebral palsy was done with brainstem auditory evoked potentials (BAEP) and correlated with brain magnetic resonance imaging findings (MRI); 12 boys and 9 girls between 5 and 12 years old were studied. All children had follow-up at the Institute of Orthopedics and Traumatology of Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The control group was done with 17 children, 10 boys and 7 girls (mean age 8.06 years, SD 2.27 years). The BAEP abnormalities were: decrease of latency of wave V; decrease of latency III-V and I-IV intervals at the right side. All patients has MRI supratentorial abnormalities and 11 had brainstem atrophy. The MRI pathologic findings were: ventricular enlargement (n=17 or 80.95%), cortical/subcortical atrophy (n=15 or 71.42%), left brainstem atrophy (n=11 or 52.38%), periventricular leukomalacia (n=10 or 47.61%), infarction in the left middle cerebral artery territory (n=6 or 28.57%), and malformations such as schizencephaly and colpocephaly (n=5 or 23.80%). The findings of the decrease latencies in children with cerebral palsy suggest the contribution of decussating auditory fibers at the lower and upper pons and midbrain, the lack of homogeneity of the surrounding volume of the conductor fibres and the presence of several concurrently active potential generators sources, should be facilitating mechanisms for the nervous input to brainstem. (author)

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...

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

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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.

LANGUAGE EXPERIENCE SHAPES PROCESSING OF PITCH RELEVANT INFORMATION IN THE HUMAN BRAINSTEM AND AUDITORY CORTEX: ELECTROPHYSIOLOGICAL EVIDENCE.

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Krishnan, Ananthanarayan; Gandour, Jackson T

2014-12-01

Pitch is a robust perceptual attribute that plays an important role in speech, language, and music. As such, it provides an analytic window to evaluate how neural activity relevant to pitch undergo transformation from early sensory to later cognitive stages of processing in a well coordinated hierarchical network that is subject to experience-dependent plasticity. We review recent evidence of language experience-dependent effects in pitch processing based on comparisons of native vs. nonnative speakers of a tonal language from electrophysiological recordings in the auditory brainstem and auditory cortex. We present evidence that shows enhanced representation of linguistically-relevant pitch dimensions or features at both the brainstem and cortical levels with a stimulus-dependent preferential activation of the right hemisphere in native speakers of a tone language. We argue that neural representation of pitch-relevant information in the brainstem and early sensory level processing in the auditory cortex is shaped by the perceptual salience of domain-specific features. While both stages of processing are shaped by language experience, neural representations are transformed and fundamentally different at each biological level of abstraction. The representation of pitch relevant information in the brainstem is more fine-grained spectrotemporally as it reflects sustained neural phase-locking to pitch relevant periodicities contained in the stimulus. In contrast, the cortical pitch relevant neural activity reflects primarily a series of transient temporal neural events synchronized to certain temporal attributes of the pitch contour. We argue that experience-dependent enhancement of pitch representation for Chinese listeners most likely reflects an interaction between higher-level cognitive processes and early sensory-level processing to improve representations of behaviorally-relevant features that contribute optimally to perception. It is our view that long

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

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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 (pwave C and the interpeak latencies of A-C elicited by verbal stimuli were found to be increased in the dyslexic group in comparison with the control group (p=0.0004 and p=0.045, respectively). In the subgroup consisting of 10 patients suffering from

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

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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.

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......). 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...

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

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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.

A comparison of auditory brainstem responses across diving bird species

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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.

Working memory capacity and visual-verbal cognitive load modulate auditory-sensory gating in the brainstem: toward a unified view of attention.

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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.

The maturational process of the auditory system in the first year of life characterized by brainstem auditory evoked potentials

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Raquel Beltrão Amorim

2009-01-01

Full Text Available The study of brainstem auditory evoked potentials (BAEP allows obtaining the electrophysiological activity generated in the cochlear nerve to the inferior colliculus. In the first months of life, a period of greater neuronal plasticity, important changes are observed in the absolute latency and inter-peak intervals of BAEP, which occur up to the completion of the maturational process, around 18 months of life in full-term newborns, when the response is similar to that of adults. OBJECTIVE: The goal of this study was to establish normal values of absolute latencies for waves I, III and V and inter-peak intervals I-III, III-V and I-V of the BAEP performed in full-term infants attending the Infant Hearing Health Program of the Speech-Language Pathology and Audiology Course at Bauru School of Dentistry, Brazil, with no risk history for hearing impairment. MATERIAL AND METHODS: The stimulation parameters were: rarefaction click stimulus presented by the 3ª insertion phone, intensity of 80 dBnHL and a rate of 21.1 c/s, band-pass filter of 30 and 3,000 Hz and average of 2,000 stimuli. A sample of 86 infants was first divided according to their gestational age in preterm (n=12 and full-term (n=74, and then according to their chronological age in three periods: P1: 0 to 29 days (n=46, P2: 30 days to 5 months 29 days (n=28 and P3: above 6 months (n= 12. RESULTS: The absolute latency of wave I was similar to that of adults, generally in the 1st month of life, demonstrating a complete process maturity of the auditory nerve. For waves III and V, there was a gradual decrease of absolute latencies with age, characterizing the maturation of axons and synaptic mechanisms in the brainstem level. CONCLUSION: Age proved to be a determining factor in the absolute latency of the BAEP components, especially those generated in the brainstem, in the first year of life.

Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

DEFF Research Database (Denmark)

Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

2017-01-01

In rodent models, acoustic exposure too modest to elevate hearing thresholds can nonetheless cause auditory nerve fiber deafferentation, interfering with the coding of supra-threshold sound. Low-spontaneous rate nerve fibers, important for encoding acoustic information at supra-threshold levels...... and in noise, are more susceptible to degeneration than high-spontaneous rate fibers. The change in auditory brainstem response (ABR) wave-V latency with noise level has been shown to be associated with auditory nerve deafferentation. Here, we measured ABR in a forward masking paradigm and evaluated wave......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

Loud Music Exposure and Cochlear Synaptopathy in Young Adults: Isolated Auditory Brainstem Response Effects but No Perceptual Consequences.

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Grose, John H; Buss, Emily; Hall, Joseph W

2017-01-01

The purpose of this study was to test the hypothesis that listeners with frequent exposure to loud music exhibit deficits in suprathreshold auditory performance consistent with cochlear synaptopathy. Young adults with normal audiograms were recruited who either did ( n = 31) or did not ( n = 30) have a history of frequent attendance at loud music venues where the typical sound levels could be expected to result in temporary threshold shifts. A test battery was administered that comprised three sets of procedures: (a) electrophysiological tests including distortion product otoacoustic emissions, auditory brainstem responses, envelope following responses, and the acoustic change complex evoked by an interaural phase inversion; (b) psychoacoustic tests including temporal modulation detection, spectral modulation detection, and sensitivity to interaural phase; and (c) speech tests including filtered phoneme recognition and speech-in-noise recognition. The results demonstrated that a history of loud music exposure can lead to a profile of peripheral auditory function that is consistent with an interpretation of cochlear synaptopathy in humans, namely, modestly abnormal auditory brainstem response Wave I/Wave V ratios in the presence of normal distortion product otoacoustic emissions and normal audiometric thresholds. However, there were no other electrophysiological, psychophysical, or speech perception effects. The absence of any behavioral effects in suprathreshold sound processing indicated that, even if cochlear synaptopathy is a valid pathophysiological condition in humans, its perceptual sequelae are either too diffuse or too inconsequential to permit a simple differential diagnosis of hidden hearing loss.

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

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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.

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.

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

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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.

Auditory Brainstem Responses and EMFs Generated by Mobile Phones.

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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.

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.

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)

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...

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.)

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.)

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.

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.

Brainstem evoked potentials in infantile spasms

International Nuclear Information System (INIS)

Miyazaki, Masahito; Hashimoto, Toshiaki; Murakawa, Kazuyoshi; Tayama, Masanobu; Kuroda, Yasuhiro

1992-01-01

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)

Brainstem Auditory Evoked Potentials in Patients with Subarachnoid Haemorrhage

Directory of Open Access Journals (Sweden)

Mikhail Matveev

2009-10-01

Full Text Available Objective. The aim of the present study is to typify BAEPs configurations of patients with different location of lesions caused by subarachnoid haemorrhage (SAH and the ensuing complications, in view of assessing the auditory-brainstem system disturbance.Methods. The typization was performed by comparing BAEPs with standard patterns from two sets of types of BAEPs by ipsilateral and binaural stimulation and by cross-stimulation.Results. 94 BAEPs were used for collection of normal referential values: for the absolute latencies and the absolute amplitudes of waves I, II, III, IV and V; for inter-peak latencies I-III, II-III, III-V, I-V and II-V; for amplitude ratios I/V and III/V. 146 BAEPs of patients with mild SAH and 55 from patients with severe SAH, were typified. In 5 types of BAEPs out of a total of 11, the percentage of the potentials in patients with mild SAH and severe SAH differed significantly (p<0.01.Conclusions. The use of sets of types of BAEPs by ipsilateral, binaural and cross-stimulation correctly classifies the potentials in patients with mild and severe SAH.

Potenciais evocados auditivos de tronco encefálico em usuários de crack e múltiplas drogas Auditory brainstem evoked potentials in crack and multiple drugs addicts

Directory of Open Access Journals (Sweden)

Loretta Fabianni Nigri

2009-01-01

Full Text Available OBJETIVO: Analisar os potenciais evocados auditivos de tronco encefálico em usuários de crack e múltiplas drogas, bem como levantar as possíveis queixas auditivas e de equilíbrio nesta população. MÉTODOS: Foram avaliados 40 usuários de drogas (20 com uso há mais de cinco anos e 20 há menos de cinco anos e 20 não usuários, do sexo masculino, com idades entre 19 e 46 anos, com limiares auditivos dentro da normalidade. RESULTADOS: Não houve diferenças significativas dos potenciais evocados auditivos de tronco encefálico dos usuários de drogas quando comparados ao grupo controle. CONCLUSÃO: Os potenciais evocados auditivos de tronco encefálico dos usuários de drogas não diferiram significantemente do grupo controle. As queixas apresentadas pelos usuários de drogas foram hiperacusia, alucinação auditiva, zumbido e alteração de equilíbrio.PURPOSE: To study the findings of auditory brainstem evoked potentials in crack and multiple drugs users, as well as to raise possible auditory and balance complaints in this population. METHODS: A total of 40 drugs addicts (20 who had been using drugs for over five years and 20 for less than five years and 20 non-users were evaluated. Subjects were all male, with ages ranging from 19 to 46 years, and had auditory thresholds within normal. RESULTS: No significant statistical differences were found regarding the auditory brainstem evoked potentials findings of the addicts group, when compared to the non-users. CONCLUSION: Auditory brainstem evoked potentials in crack and multiple drugs users did not differ significantly from the control group. Complaints presented by drugs addicts were hyperacusis, auditory hallucination, tinnitus and altered balance.

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.

Detection of brainstem involvemetn in multiple sclerosis

International Nuclear Information System (INIS)

Martinelli, V.; Comi, G.; Filippi, M.; Sora, M.G.N.; Magnani, G.; Locatelli, T.; Visciani, A.; Scotti, G.; Canal, N.

1989-01-01

The Gradient Refocusing Technique, which seppresses the influence of cerebrospinal fluis (GSF) and vascular motion artifact on MRI sensitivity, is applied combined with Brainstem Auditory Evoked Potentials (BAEPs) and median Somatosensory Evoked Potentials (SEPs) in the evaluation of the brainstem in 30 MS patients with clinical signs of involvement of this structure in order to reevaluate the sensitivity of these techniques. (Author). 2 refs.; 1 tab

Age-Related Changes in Binaural Interaction at Brainstem Level.

Science.gov (United States)

Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Beynon, Andy J; Dhooge, Ingeborg J M

2016-01-01

Age-related hearing loss hampers the ability to understand speech in adverse listening conditions. This is attributed to a complex interaction of changes in the peripheral and central auditory system. One aspect that may deteriorate across the lifespan is binaural interaction. The present study investigates binaural interaction at the level of the auditory brainstem. It is hypothesized that brainstem binaural interaction deteriorates with advancing age. Forty-two subjects of various age participated in the study. Auditory brainstem responses (ABRs) were recorded using clicks and 500 Hz tone-bursts. ABRs were elicited by monaural right, monaural left, and binaural stimulation. Binaural interaction was investigated in two ways. First, grand averages of the binaural interaction component were computed for each age group. Second, wave V characteristics of the binaural ABR were compared with those of the summed left and right ABRs. Binaural interaction in the click ABR was demonstrated by shorter latencies and smaller amplitudes in the binaural compared with the summed monaural responses. For 500 Hz tone-burst ABR, no latency differences were found. However, amplitudes were significantly smaller in the binaural than summed monaural condition. An age-effect was found for 500 Hz tone-burst, but not for click ABR. Brainstem binaural interaction seems to decline with age. Interestingly, these changes seem to be stimulus-dependent.

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.

Speech auditory brainstem response (speech ABR) characteristics depending on recording conditions, and hearing status: an experimental parametric study.

Science.gov (United States)

Akhoun, Idrick; Moulin, Annie; Jeanvoine, Arnaud; Ménard, Mikael; Buret, François; Vollaire, Christian; Scorretti, Riccardo; Veuillet, Evelyne; Berger-Vachon, Christian; Collet, Lionel; Thai-Van, Hung

2008-11-15

Speech elicited auditory brainstem responses (Speech ABR) have been shown to be an objective measurement of speech processing in the brainstem. Given the simultaneous stimulation and recording, and the similarities between the recording and the speech stimulus envelope, there is a great risk of artefactual recordings. This study sought to systematically investigate the source of artefactual contamination in Speech ABR response. In a first part, we measured the sound level thresholds over which artefactual responses were obtained, for different types of transducers and experimental setup parameters. A watermelon model was used to model the human head susceptibility to electromagnetic artefact. It was found that impedances between the electrodes had a great effect on electromagnetic susceptibility and that the most prominent artefact is due to the transducer's electromagnetic leakage. The only artefact-free condition was obtained with insert-earphones shielded in a Faraday cage linked to common ground. In a second part of the study, using the previously defined artefact-free condition, we recorded speech ABR in unilateral deaf subjects and bilateral normal hearing subjects. In an additional control condition, Speech ABR was recorded with the insert-earphones used to deliver the stimulation, unplugged from the ears, so that the subjects did not perceive the stimulus. No responses were obtained from the deaf ear of unilaterally hearing impaired subjects, nor in the insert-out-of-the-ear condition in all the subjects, showing that Speech ABR reflects the functioning of the auditory pathways.

Experiences from Auditory Brainstem Implantation (ABIs) in four paediatric patients.

Science.gov (United States)

Lundin, Karin; Stillesjö, Fredrik; Nyberg, Gunnar; Rask-Andersen, Helge

2016-01-01

Indications for auditory brainstem implants (ABIs) have been widened from patients with neurofibromatosis type 2 (NF2) to paediatric patients with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, or cochlear ossification after meningitis. We present four ABI surgeries performed in children at Uppsala University Hospital in Sweden since 2009. Three children were implanted with implants from Cochlear Ltd. (Lane Cove, Australia) and one child with an implant from MedEl GMBH (Innsbruck, Austria). A boy with Goldenhar syndrome was implanted with a Cochlear Nucleus ABI24M at age 2 years (patient 1). Another boy with CHARGE syndrome was implanted with a Cochlear Nucleus ABI541 at age 2.5 years (patient 2). Another boy with post-ossification meningitis was implanted with a Cochlear Nucleus ABI24M at age 4 years (patient 3). A girl with cochlear aplasia was implanted with a MedEl Synchrony ABI at age 3 years (patient 4). In patients 1, 2, and 3, the trans-labyrinthine approach was used, and in patient 4 the retro-sigmoid approach was used. Three of the four children benefited from their ABIs and use it full time. Two of the full time users had categories of auditory performance (CAP) score of 4 at their last follow up visit (6 and 2.5 years postoperative) which means they can discriminate consistently any combination of two of Ling's sounds. One child has not been fully evaluated yet, but is a full time user and had CAP 2 (responds to speech sounds) after 3 months of ABI use. No severe side or unpleasant stimulation effects have been observed so far. There was one case of immediate electrode migration and one case of implant device failure after 6.5 years. ABI should be considered as an option in the rehabilitation of children with similar diagnoses.

Brainstem response audiometry in the determination of low-frequency hearing loss : a study of various methods for frequency-specific ABR-threshold assessment

NARCIS (Netherlands)

E.A.G.J. Conijn

1992-01-01

textabstractBrainstem Electric Response Audiometry (BERA) is a method to visualize some of the electric activity generated in the auditory nerve and the brainstem during the processing of sound. The amplitude of the Auditory Brainstem Response (ABR) is very small (0.05-0.5 flV). The potentials

Reduced auditory efferent activity in childhood selective mutism.

Science.gov (United States)

Bar-Haim, Yair; Henkin, Yael; Ari-Even-Roth, Daphne; Tetin-Schneider, Simona; Hildesheimer, Minka; Muchnik, Chava

2004-06-01

Selective mutism is a psychiatric disorder of childhood characterized by consistent inability to speak in specific situations despite the ability to speak normally in others. The objective of this study was to test whether reduced auditory efferent activity, which may have direct bearings on speaking behavior, is compromised in selectively mute children. Participants were 16 children with selective mutism and 16 normally developing control children matched for age and gender. All children were tested for pure-tone audiometry, speech reception thresholds, speech discrimination, middle-ear acoustic reflex thresholds and decay function, transient evoked otoacoustic emission, suppression of transient evoked otoacoustic emission, and auditory brainstem response. Compared with control children, selectively mute children displayed specific deficiencies in auditory efferent activity. These aberrations in efferent activity appear along with normal pure-tone and speech audiometry and normal brainstem transmission as indicated by auditory brainstem response latencies. The diminished auditory efferent activity detected in some children with SM may result in desensitization of their auditory pathways by self-vocalization and in reduced control of masking and distortion of incoming speech sounds. These children may gradually learn to restrict vocalization to the minimal amount possible in contexts that require complex auditory processing.

The pattern of auditory brainstem response wave V maturation in cochlear-implanted children.

Science.gov (United States)

Thai-Van, Hung; Cozma, Sebastian; Boutitie, Florent; Disant, François; Truy, Eric; Collet, Lionel

2007-03-01

Maturation of acoustically evoked brainstem responses (ABR) in hearing children is not complete at birth but rather continues over the first two years of life. In particular, it has been established that the decrease in ABR wave V latency can be modeled as the sum of two decaying exponential functions with respective time-constants of 4 and 50 weeks [Eggermont, J.J., Salamy, A., 1988a. Maturational time-course for the ABR in preterm and full term infants. Hear Res 33, 35-47; Eggermont, J.J., Salamy, A., 1988b. Development of ABR parameters in a preterm and a term born population. Ear Hear 9, 283-9]. Here, we investigated the maturation of electrically evoked auditory brainstem responses (EABR) in 55 deaf children who recovered hearing after cochlear implantation, and proposed a predictive model of EABR maturation depending on the onset of deafness. The pattern of EABR maturation over the first 2 years of cochlear implant use was compared with the normal pattern of ABR maturation in hearing children. Changes in EABR wave V latency over the 2 years following cochlear implant connection were analyzed in two groups of children. The first group (n=41) consisted of children with early-onset of deafness (mostly congenital), and the second (n=14) of children who had become profoundly deaf after 1 year of age. The modeling of changes in EABR wave V latency with time was based on the mean values from each of the two groups, allowing comparison of the rates of EABR maturation between groups. Differences between EABRs elicited at the basal and apical ends of the implant electrode array were also tested. There was no influence of age at implantation on the rate of wave V latency change. The main factor for EABR changes was the time in sound. Indeed, significant maturation was observed over the first 2 years of implant use only in the group with early-onset deafness. In this group maturation of wave V progressed as in the ABR model of [Eggermont, J.J., Salamy, A., 1988a

Auditory brainstem response screening for hearing loss in high risk neonates.

Science.gov (United States)

Watson, D R; McClelland, R J; Adams, D A

1996-07-01

The present paper reports the findings of a 7 year study evaluating the use of the auditory brainstem response (ABR) as the basis of a hearing screening procedure in a group of newborns at increased risk of hearing impairment. A Special Care Baby Unit (SCBU) population of 417 infants with diverse clinical backgrounds and treatment histories was tested for hearing impairment at birth using ABR audiometry. Some 332 passed the original screen at 30 dBnHL test level in both ears. Of the failure group, 18 did not survive and 32 had some degree of hearing impairment confirmed, nine of which were sensorineural in origin. An increased incidence of persistent middle ear disease was also noted in the failure group. A detailed operational analysis demonstrates that provided appropriate pass/fail criteria are adopted, the ABR technique offers excellent sensitivity and specificity for the detection of significant hearing loss in the test population. Furthermore, the study establishes that implementation of an ABR-based screening programme could reduce the average age at detection of permanent hearing loss by 7 months. A cost assessment shows that the introduction of such a targetted screening procedure could be done at a reasonable outlay.

Graded and discontinuous EphA-ephrinB expression patterns in the developing auditory brainstem.

Science.gov (United States)

Wallace, Matthew M; Harris, J Aaron; Brubaker, Donald Q; Klotz, Caitlyn A; Gabriele, Mark L

2016-05-01

Eph-ephrin interactions guide topographic mapping and pattern formation in a variety of systems. In contrast to other sensory pathways, their precise role in the assembly of central auditory circuits remains poorly understood. The auditory midbrain, or inferior colliculus (IC) is an intriguing structure for exploring guidance of patterned projections as adjacent subdivisions exhibit distinct organizational features. The central nucleus of the IC (CNIC) and deep aspects of its neighboring lateral cortex (LCIC, Layer 3) are tonotopically-organized and receive layered inputs from primarily downstream auditory sources. While less is known about more superficial aspects of the LCIC, its inputs are multimodal, lack a clear tonotopic order, and appear discontinuous, terminating in modular, patch/matrix-like distributions. Here we utilize X-Gal staining approaches in lacZ mutant mice (ephrin-B2, -B3, and EphA4) to reveal EphA-ephrinB expression patterns in the nascent IC during the period of projection shaping that precedes hearing onset. We also report early postnatal protein expression in the cochlear nuclei, the superior olivary complex, the nuclei of the lateral lemniscus, and relevant midline structures. Continuous ephrin-B2 and EphA4 expression gradients exist along frequency axes of the CNIC and LCIC Layer 3. In contrast, more superficial LCIC localization is not graded, but confined to a series of discrete ephrin-B2 and EphA4-positive Layer 2 modules. While heavily expressed in the midline, much of the auditory brainstem is devoid of ephrin-B3, including the CNIC, LCIC Layer 2 modular fields, the dorsal nucleus of the lateral lemniscus (DNLL), as well as much of the superior olivary complex and cochlear nuclei. Ephrin-B3 LCIC expression appears complementary to that of ephrin-B2 and EphA4, with protein most concentrated in presumptive extramodular zones. Described tonotopic gradients and seemingly complementary modular/extramodular patterns suggest Eph

Lateralization and Binaural Interaction of Middle-Latency and Late-Brainstem Components of the Auditory Evoked Response.

Science.gov (United States)

Dykstra, Andrew R; Burchard, Daniel; Starzynski, Christian; Riedel, Helmut; Rupp, Andre; Gutschalk, Alexander

2016-08-01

We used magnetoencephalography to examine lateralization and binaural interaction of the middle-latency and late-brainstem components of the auditory evoked response (the MLR and SN10, respectively). Click stimuli were presented either monaurally, or binaurally with left- or right-leading interaural time differences (ITDs). While early MLR components, including the N19 and P30, were larger for monaural stimuli presented contralaterally (by approximately 30 and 36 % in the left and right hemispheres, respectively), later components, including the N40 and P50, were larger ipsilaterally. In contrast, MLRs elicited by binaural clicks with left- or right-leading ITDs did not differ. Depending on filter settings, weak binaural interaction could be observed as early as the P13 but was clearly much larger for later components, beginning at the P30, indicating some degree of binaural linearity up to early stages of cortical processing. The SN10, an obscure late-brainstem component, was observed consistently in individuals and showed linear binaural additivity. The results indicate that while the MLR is lateralized in response to monaural stimuli-and not ITDs-this lateralization reverses from primarily contralateral to primarily ipsilateral as early as 40 ms post stimulus and is never as large as that seen with fMRI.

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

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.

Auditory Brainstem Implantation in Chinese Patients With Neurofibromatosis Type II: The Hong Kong Experience.

Science.gov (United States)

Thong, Jiun Fong; Sung, John K K; Wong, Terence K C; Tong, Michael C F

2016-08-01

To describe our experience and outcomes of auditory brainstem implantation (ABI) in Chinese patients with Neurofibromatosis Type II (NF2). Retrospective case review. Tertiary referral center. Patients with NF2 who received ABIs. Between 1997 and 2014, eight patients with NF2 received 9 ABIs after translabyrinthine removal of their vestibular schwannomas. One patient did not have auditory response using the ABI after activation. Environmental sounds could be differentiated by six (75%) patients after 6 months of ABI use (mean score 46% [range 28-60%]), and by five (63%) patients after 1 year (mean score 57% [range 36-76%]) and 2 years of ABI use (mean score 48% [range 24-76%]). Closed-set word identification was possible in four (50%) patients after 6 months (mean score 39% [range 12-72%]), 1 year (mean score 68% [range 48-92%]), and 2 years of ABI use (mean score 62% [range 28-100%]). No patient demonstrated open-set sentence recognition in quiet in the ABI-only condition. However, the use of ABI together with lip-reading conferred an improvement over lip-reading alone in open-set sentence recognition scores in two (25%) patients after 6 months of ABI use (mean improvement 46%), and five (63%) patients after 1 year (mean improvement 25%) and 2 years of ABI use (mean improvement 28%). At 2 years postoperatively, three (38%) patients remained ABI users. This is the only published study to date examining ABI outcomes in Cantonese-speaking Chinese NF2 patients and the data seems to show poorer outcomes compared with English-speaking and other nontonal language-speaking NF2 patients. Environmental sound awareness and lip-reading enhancement are the main benefits observed in our patients. More work is needed to improve auditory implant speech-processing strategies for tonal languages and these advancements may yield better speech perception outcomes in the future.

Effects of myelin or cell body brainstem lesions on 3-channel Lissajous' trajectories of feline auditory brainstem evoked potentials.

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Pratt, H; Zaaroor, M; Bleich, N; Starr, A

1991-06-01

Auditory brainstem evoked potentials (ABEP) were recorded from 16 awake cats to obtain 3-Channel Lissajous' Trajectories (3CLTs) using three orthogonal differential electrode configurations (nasion-midline nuchal ridge, left-right mastoids, vertex-midline under the mandible). Potentials, evoked by monaural 80 dBnHL (re, human threshold) clicks, were studied before, and up to 7 weeks after inducing neuronal lesions localized to the cochlear nucleus (CN) or the superior olivary complex (SOC), or myelin lesions localized to the fibers of the trapezoid body connecting these two structures. Neuronal lesions were induced by injection of kainic acid (KA), while myelin lesions were induced by injection of L-alpha-lysophosphatidylcholine (LPC). With CN neuronal lesions the major changes in 3CLT were in the time domain of 'b', 'c' and 'd' (components P2, P3 and P4 of single-channel ABEP). With SOC neuronal lesions the major changes were in 'c' and 'd' of 3CLT (P3 and P4 of ABEP). With trapezoid body lesions the major change was in 'c' (P3 of ABEP). The results are compatible with the peripheral generation of the first ABEP components (P1a and P1b). The second component (P2) is generated by ipsilateral CN neurones and their outputs. The third component (P3) is generated primarily by ipsilateral SOC neurones and their outputs, with the ipsilateral CN providing input. The The fourth component (P4) is generated bilaterally by the SOC neurones and their outputs, receiving their inputs from ipsilateral CN. The fifth ABEP component (P5) is generated by structures central to the SOCs and their immediate outputs. Neither focal neuronal nor myelin lesions were sufficient to produce obliteration of any component, consistent with a set of generators for each of the ABEP components, consisting of both cell bodies and their output fibers, that is distributed spatially in the brainstem.

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

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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

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

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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.

Adult plasticity in the subcortical auditory pathway of the maternal mouse.

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Jason A Miranda

Full Text Available Subcortical auditory nuclei were traditionally viewed as non-plastic in adulthood so that acoustic information could be stably conveyed to higher auditory areas. Studies in a variety of species, including humans, now suggest that prolonged acoustic training can drive long-lasting brainstem plasticity. The neurobiological mechanisms for such changes are not well understood in natural behavioral contexts due to a relative dearth of in vivo animal models in which to study this. Here, we demonstrate in a mouse model that a natural life experience with increased demands on the auditory system - motherhood - is associated with improved temporal processing in the subcortical auditory pathway. We measured the auditory brainstem response to test whether mothers and pup-naïve virgin mice differed in temporal responses to both broadband and tone stimuli, including ultrasonic frequencies found in mouse pup vocalizations. Mothers had shorter latencies for early ABR peaks, indicating plasticity in the auditory nerve and the cochlear nucleus. Shorter interpeak latency between waves IV and V also suggest plasticity in the inferior colliculus. Hormone manipulations revealed that these cannot be explained solely by estrogen levels experienced during pregnancy and parturition in mothers. In contrast, we found that pup-care experience, independent of pregnancy and parturition, contributes to shortening auditory brainstem response latencies. These results suggest that acoustic experience in the maternal context imparts plasticity on early auditory processing that lasts beyond pup weaning. In addition to establishing an animal model for exploring adult auditory brainstem plasticity in a neuroethological context, our results have broader implications for models of perceptual, behavioral and neural changes that arise during maternity, where subcortical sensorineural plasticity has not previously been considered.

Adult plasticity in the subcortical auditory pathway of the maternal mouse.

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Miranda, Jason A; Shepard, Kathryn N; McClintock, Shannon K; Liu, Robert C

2014-01-01

Subcortical auditory nuclei were traditionally viewed as non-plastic in adulthood so that acoustic information could be stably conveyed to higher auditory areas. Studies in a variety of species, including humans, now suggest that prolonged acoustic training can drive long-lasting brainstem plasticity. The neurobiological mechanisms for such changes are not well understood in natural behavioral contexts due to a relative dearth of in vivo animal models in which to study this. Here, we demonstrate in a mouse model that a natural life experience with increased demands on the auditory system - motherhood - is associated with improved temporal processing in the subcortical auditory pathway. We measured the auditory brainstem response to test whether mothers and pup-naïve virgin mice differed in temporal responses to both broadband and tone stimuli, including ultrasonic frequencies found in mouse pup vocalizations. Mothers had shorter latencies for early ABR peaks, indicating plasticity in the auditory nerve and the cochlear nucleus. Shorter interpeak latency between waves IV and V also suggest plasticity in the inferior colliculus. Hormone manipulations revealed that these cannot be explained solely by estrogen levels experienced during pregnancy and parturition in mothers. In contrast, we found that pup-care experience, independent of pregnancy and parturition, contributes to shortening auditory brainstem response latencies. These results suggest that acoustic experience in the maternal context imparts plasticity on early auditory processing that lasts beyond pup weaning. In addition to establishing an animal model for exploring adult auditory brainstem plasticity in a neuroethological context, our results have broader implications for models of perceptual, behavioral and neural changes that arise during maternity, where subcortical sensorineural plasticity has not previously been considered.

Auditory brainstem response in neonates: influence of gender and weight/gestational age ratio

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Rosanna M. Giaffredo Angrisani

2013-12-01

Full Text Available OBJECTIVE: To investigate the influence of gender and weight/gestational age ratio on the Auditory Brainstem Response (ABR in preterm (PT and term (T newborns. METHODS: 176 newborns were evaluated by ABR; 88 were preterm infants - 44 females (22 small and 22 appropriate for gestational age and 44 males (22 small and 22 appropriate for gestational age. The preterm infants were compared to 88 term infants - 44 females (22 small and 22 appropriate for gestational age and 44 males (22 small and 22 appropriate for gestational age. All newborns had bilateral presence of transient otoacoustic emissions and type A tympanometry. RESULTS: No interaural differences were found. ABR response did not differentiate newborns regarding weight/gestational age in males and females. Term newborn females showed statistically shorter absolute latencies (except on wave I than males. This finding did not occur in preterm infants, who had longer latencies than term newborns, regardless of gender. CONCLUSIONS: Gender and gestational age influence term infants' ABR, with lower responses in females. The weight/gestational age ratio did not influence ABR response in either groups.

Auditory brainstem response as a diagnostic tool for patients suffering from schizophrenia, attention deficit hyperactivity disorder, and bipolar disorder: protocol.

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Wahlström, Viktor; Åhlander, Fredrik; Wynn, Rolf

2015-02-12

Psychiatric disorders, such as schizophrenia, attention deficit hyperactivity disorder (ADHD), and bipolar disorder, may sometimes be difficult to diagnose. There is a great need for a valid and reliable diagnostic tool to aid clinicians in arriving at the diagnoses in a timely and accurate manner. Prior studies have suggested that patients suffering from schizophrenia and ADHD may process certain sound stimuli in the brainstem in an unusual manner. When these patient groups have been examined with the electrophysiological method of brainstem audiometry, some studies have found illness-specific aberrations. Such aberrations may also exist for patients suffering from bipolar disorder. In this study, we will examine whether the method of brainstem audiometry can be used as a diagnostic tool for patients suffering from schizophrenia, ADHD, and bipolar disorder. The method includes three steps: (1) auditory stimulation with specific sound stimuli, (2) simultaneous measurement of brainstem activity, and (3) automated interpretation of the resulting brain stem audiograms with data-based signal analysis. We will compare three groups of 12 individuals with confirmed diagnoses of schizophrenia, ADHD, or bipolar disorder with 12 healthy subjects under blinded conditions for a total of 48 participants. The extent to which the method can be used to reach the correct diagnosis will be investigated. The project is now in a recruiting phase. When all patients and controls have been recruited and the measurements have been performed, the data will be analyzed according to a previously arranged algorithm. We expect the recruiting phase and measurements to be completed in early 2015, the analyses to be performed in mid-2015, and the results of the study to be published in early 2016. If the results support previous findings, this will lend strength to the idea that brainstem audiometry can offer objective diagnostic support for patients suffering from schizophrenia, ADHD, and

Auditory midbrain processing is differentially modulated by auditory and visual cortices: An auditory fMRI study.

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Gao, Patrick P; Zhang, Jevin W; Fan, Shu-Juan; Sanes, Dan H; Wu, Ed X

2015-12-01

The cortex contains extensive descending projections, yet the impact of cortical input on brainstem processing remains poorly understood. In the central auditory system, the auditory cortex contains direct and indirect pathways (via brainstem cholinergic cells) to nuclei of the auditory midbrain, called the inferior colliculus (IC). While these projections modulate auditory processing throughout the IC, single neuron recordings have samples from only a small fraction of cells during stimulation of the corticofugal pathway. Furthermore, assessments of cortical feedback have not been extended to sensory modalities other than audition. To address these issues, we devised blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) paradigms to measure the sound-evoked responses throughout the rat IC and investigated the effects of bilateral ablation of either auditory or visual cortices. Auditory cortex ablation increased the gain of IC responses to noise stimuli (primarily in the central nucleus of the IC) and decreased response selectivity to forward species-specific vocalizations (versus temporally reversed ones, most prominently in the external cortex of the IC). In contrast, visual cortex ablation decreased the gain and induced a much smaller effect on response selectivity. The results suggest that auditory cortical projections normally exert a large-scale and net suppressive influence on specific IC subnuclei, while visual cortical projections provide a facilitatory influence. Meanwhile, auditory cortical projections enhance the midbrain response selectivity to species-specific vocalizations. We also probed the role of the indirect cholinergic projections in the auditory system in the descending modulation process by pharmacologically blocking muscarinic cholinergic receptors. This manipulation did not affect the gain of IC responses but significantly reduced the response selectivity to vocalizations. The results imply that auditory cortical

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

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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.

Brain-stem evoked potentials and noise effects in seagulls.

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Counter, S A

1985-01-01

Brain-stem auditory evoked potentials (BAEP) recorded from the seagull were large-amplitude, short-latency, vertex-positive deflections which originate in the eighth nerve and several brain-stem nuclei. BAEP waveforms were similar in latency and configurations to that reported for certain other lower vertebrates and some mammals. BAEP recorded at several pure tone frequencies throughout the seagull's auditory spectrum showed an area of heightened auditory sensitivity between 1 and 3 kHz. This range was also found to be the primary bandwidth of the vocalization output of young seagulls. Masking by white noise and pure tones had remarkable effects on several parameters of the BAEP. In general, the tone- and click-induced BAEP were either reduced or obliterated by both pure tone and white noise maskers of specific signal to noise ratios and high intensity levels. The masking effects observed in this study may be related to the manner in which seagulls respond to intense environmental noise. One possible conclusion is that intense environmental noise, such as aircraft engine noise, may severely alter the seagull's localization apparatus and induce sonogenic stress, both of which could cause collisions with low-flying aircraft.

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

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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.

Auditory agnosia due to long-term severe hydrocephalus caused by spina bifida - specific auditory pathway versus nonspecific auditory pathway.

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Zhang, Qing; Kaga, Kimitaka; Hayashi, Akimasa

2011-07-01

A 27-year-old female showed auditory agnosia after long-term severe hydrocephalus due to congenital spina bifida. After years of hydrocephalus, she gradually suffered from hearing loss in her right ear at 19 years of age, followed by her left ear. During the time when she retained some ability to hear, she experienced severe difficulty in distinguishing verbal, environmental, and musical instrumental sounds. However, her auditory brainstem response and distortion product otoacoustic emissions were largely intact in the left ear. Her bilateral auditory cortices were preserved, as shown by neuroimaging, whereas her auditory radiations were severely damaged owing to progressive hydrocephalus. Although she had a complete bilateral hearing loss, she felt great pleasure when exposed to music. After years of self-training to read lips, she regained fluent ability to communicate. Clinical manifestations of this patient indicate that auditory agnosia can occur after long-term hydrocephalus due to spina bifida; the secondary auditory pathway may play a role in both auditory perception and hearing rehabilitation.

Auditory temporal processing tests – Normative data for Polish-speaking adults

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Joanna Majak

2015-04-01

Full Text Available Introduction: Several subjects exposed to neurotoxins in the workplace need to be assessed for central auditory deficit. Although central auditory processing tests are widely used in other countries, they have not been standardized for the Polish population. The aim of the study has been to evaluate the range of reference values for 3 temporal processing tests: the duration pattern test (DPT, the frequency pattern test (FPT and the gaps in noise test (GIN. Material and Methods: The study included 76 normal hearing individuals (38 women, 38 men at the age of 18 to 54 years old (mean ± standard deviation: 39.4±9.1. All study participants had no history of any chronic disease and underwent a standard ENT examination. Results: The reference range for the DPT was established at 55.3% or more of correct answers, while for the FPT it stood at 56.7% or more of correct answers. The mean threshold for both ears in the GIN test was defined as 6 ms. In this study there were no significant associations between the DPT, FPT and GIN results and age or gender. Symmetry between the ears in the case of the DPT, FPT and GIN was found. Conclusions: Reference ranges obtained in this study for the DPT and FPT in the Polish population are lower than reference ranges previously published for other nations while the GIN test results correspond to those published in the related literature. Further investigations are needed to explain the discrepancies between normative values in Poland and other countries and adapt tests for occupational medicine purposes. Med Pr 2015;66(2:145–152

Diverse Intrinsic Properties Shape Functional Phenotype of Low-Frequency Neurons in the Auditory Brainstem

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Hui Hong

2018-06-01

Full Text Available In the auditory system, tonotopy is the spatial arrangement of where sounds of different frequencies are processed. Defined by the organization of neurons and their inputs, tonotopy emphasizes distinctions in neuronal structure and function across topographic gradients and is a common feature shared among vertebrates. In this study we characterized action potential firing patterns and ion channel properties from neurons located in the extremely low-frequency region of the chicken nucleus magnocellularis (NM, an auditory brainstem structure. We found that NM neurons responsible for encoding the lowest sound frequencies (termed NMc neurons have enhanced excitability and fired bursts of action potentials to sinusoidal inputs ≤10 Hz; a distinct firing pattern compared to higher-frequency neurons. This response property was due to lower amounts of voltage dependent potassium (KV conductances, unique combination of KV subunits and specialized sodium (NaV channel properties. Particularly, NMc neurons had significantly lower KV1 and KV3 currents, but higher KV2 current. NMc neurons also showed larger and faster transient NaV current (INaT with different voltage dependence of inactivation from higher-frequency neurons. In contrast, significantly smaller resurgent sodium current (INaR was present in NMc with kinetics and voltage dependence that differed from higher-frequency neurons. Immunohistochemistry showed expression of NaV1.6 channel subtypes across the tonotopic axis. However, various immunoreactive patterns were observed between regions, likely underlying some tonotopic differences in INaT and INaR. Finally, using pharmacology and computational modeling, we concluded that KV3, KV2 channels and INaR work synergistically to regulate burst firing in NMc.

Comparison of sensitivity of magnetic resonance imaging and evoked potentials in the detection of brainstem involvement in multiple sclerosis

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Comi, G.; Martinelli, V.; Medaglini, S.; Locatelli, T.; Magnani, G.; Poggi, A.; Triulzi, F.

1988-01-01

A comparison was made of the sensitivity of magnetic resonance imaging and the combined use of Brainstem Auditory Evoked Potential and Median Somatosensory Evoked Potential in the detection of brainstem dysfunction in 54 multiple sclerosis patients. 10 refs.; 2 tabs

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

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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

Multi-sensory integration in brainstem and auditory cortex.

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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

Speech-evoked brainstem frequency-following responses during verbal transformations due to word repetition.

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Galbraith, G C; Jhaveri, S P; Kuo, J

1997-01-01

Speech-evoked brainstem frequency-following responses (FFRs) were recorded to repeated presentations of the same stimulus word. Word repetition results in illusory verbal transformations (VTs) in which word perceptions can differ markedly from the actual stimulus. Previous behavioral studies support an explanation of VTs based on changes in arousal or attention. Horizontal and vertical dipole FFRs were recorded to assess responses with putative origins in the auditory nerve and central brainstem, respectively. FFRs were recorded from 18 subjects when they correctly heard the stimulus and when they reported VTs. Although horizontal and vertical dipole FFRs showed different frequency response patterns, dipoles did not differentiate between perceptual conditions. However, when subjects were divided into low- and high-VT groups (based on percentage of VT trials), a significant Condition x Group interaction resulted. This interaction showed the largest difference in FFR amplitudes during VT trials, with the low-VT group showing increased amplitudes, and the high-VT group showing decreased amplitudes, relative to trials in which the stimulus was correctly perceived. These results demonstrate measurable subject differences in the early processing of complex signals, due to possible effects of attention on the brainstem FFR. The present research shows that the FFR is useful in understanding human language as it is coded and processed in the brainstem auditory pathway.

BRAINSTEM AUDITORY EVOKED POTENTIAL AS AN INDEX OF CNS DEMYELINATION IN GUILLAIN -BARRÉ SYNDROME (GBS

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Smita Singh

2016-01-01

Full Text Available Background: Guillain-Barré Syndrome (GBS is an acute, frequently severe and fulminant polyradicular neuropathy that is autoimmune in nature. GBS manifest as rapidly evolving areflexic motor paralysis with or without sensory disturbances. It mainly involves peripheral nervous system and autonomic nervous system. There are rare evidences about the involvement of central nervous system (CNS in GBS. Aims: The main objective of the study was to assess the CNS involvement in GBS using the Brainstem Auditory Evoked Potential (BAEP. Methods & Material: The study was conducted in the clinical neurophysiology lab in the department of physiology, CSMMU Lucknow. Study group involved 26 subjects (n=26 having GBS and control group involved 30 normal subjects (n=30. BAEPS were recorded by Neuroperfect- EMG 2000 EMG/NCV/EPsytem. The data so obtained were subjected to analysis using Statistical Package for Social Sciences (SPSS Version 13.0. Results & Conclusions: There was significant increase in PIII & PV peak latencies and PI-PIII & PI-PV interpeak latencies in both left and right ear in the study group, which showed the CNS involvement in GBS which can be assessed using BAEP.

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

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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.

Auditory evoked potentials: predicting speech therapy outcomes in children with phonological disorders

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Renata Aparecida Leite

2014-03-01

Full Text Available OBJECTIVES: This study investigated whether neurophysiologic responses (auditory evoked potentials differ between typically developed children and children with phonological disorders and whether these responses are modified in children with phonological disorders after speech therapy. METHODS: The participants included 24 typically developing children (Control Group, mean age: eight years and ten months and 23 children clinically diagnosed with phonological disorders (Study Group, mean age: eight years and eleven months. Additionally, 12 study group children were enrolled in speech therapy (Study Group 1, and 11 were not enrolled in speech therapy (Study Group 2. The subjects were submitted to the following procedures: conventional audiological, auditory brainstem response, auditory middle-latency response, and P300 assessments. All participants presented with normal hearing thresholds. The study group 1 subjects were reassessed after 12 speech therapy sessions, and the study group 2 subjects were reassessed 3 months after the initial assessment. Electrophysiological results were compared between the groups. RESULTS: Latency differences were observed between the groups (the control and study groups regarding the auditory brainstem response and the P300 tests. Additionally, the P300 responses improved in the study group 1 children after speech therapy. CONCLUSION: The findings suggest that children with phonological disorders have impaired auditory brainstem and cortical region pathways that may benefit from speech therapy.

Impact of monaural frequency compression on binaural fusion at the brainstem level.

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Klauke, Isabelle; Kohl, Manuel C; Hannemann, Ronny; Kornagel, Ulrich; Strauss, Daniel J; Corona-Strauss, Farah I

2015-08-01

A classical objective measure for binaural fusion at the brainstem level is the so-called β-wave of the binaural interaction component (BIC) in the auditory brainstem response (ABR). However, in some cases it appeared that a reliable detection of this component still remains a challenge. In this study, we investigate the wavelet phase synchronization stability (WPSS) of ABR data for the analysis of binaural fusion and compare it to the BIC. In particular, we examine the impact of monaural nonlinear frequency compression on binaural fusion. As the auditory system is tonotopically organized, an interaural frequency mismatch caused by monaural frequency compression could negatively effect binaural fusion. In this study, only few subjects showed a detectable β-wave and in most cases only for low ITDs. However, we present a novel objective measure for binaural fusion that outperforms the current state-of-the-art technique (BIC): the WPSS analysis showed a significant difference between the phase stability of the sum of the monaurally evoked responses and the phase stability of the binaurally evoked ABR. This difference could be an indicator for binaural fusion in the brainstem. Furthermore, we observed that monaural frequency compression could indeed effect binaural fusion, as the WPSS results for this condition vary strongly from the results obtained without frequency compression.

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.

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.

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

Auditory brainstem evoked responses and temperature monitoring during pediatric cardiopulmonary bypass.

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Rodriguez, R A; Edmonds, H L; Auden, S M; Austin, E H

1999-09-01

To examine the effects of temperature on auditory brainstem responses (ABRs) in infants during hypothermic cardiopulmonary bypass for total circulatory arrest (TCA). The relationship between ABRs (as a surrogate measure of core-brain temperature) and body temperature as measured at several temperature monitoring sites was determined. In a prospective, observational study, ABRs were recorded non-invasively at normothermia and at every 1 or 2 degrees C change in ear-canal temperature during cooling and rewarming in 15 infants (ages: 2 days to 14 months) that required TCA. The ABR latencies and amplitudes and the lowest temperatures at which an ABR was identified (the threshold) were measured during both cooling and rewarming. Temperatures from four standard temperature monitoring sites were simultaneously recorded. The latencies of ABRs increased and amplitudes decreased with cooling (P < 0.01), but rewarming reversed these effects. The ABR threshold temperature as related to each monitoring site (ear-canal, nasopharynx, esophagus and bladder) was respectively determined as 23 +/- 2.2 degrees C, 20.8 +/- 1.7 degrees C, 14.6 +/- 3.4 degrees C, and 21.5 +/- 3.8 degrees C during cooling and 21.8 +/- 1.6 degrees C, 22.4 +/- 2.0 degrees C, 27.6 +/- 3.6 degrees C, and 23.0 +/- 2.4 degrees C during rewarming. The rewarming latencies were shorter and Q10 latencies smaller than the corresponding cooling values (P < 0.01). Esophageal and bladder sites were more susceptible to temperature variations as compared with the ear-canal and nasopharynx. No temperature site reliably predicted an electrophysiological threshold. A faster latency recovery during rewarming suggests that body temperature monitoring underestimates the effects of rewarming in the core-brain. ABRs may be helpful to monitor the effects of cooling and rewarming on the core-brain during pediatric cardiopulmonary bypass.

Binaural interaction in auditory evoked potentials: Brainstem, middle- and long-latency components

OpenAIRE

McPherson, DL; Starr, A

1993-01-01

Binaural interaction occurs in the auditory evoked potentials when the sum of the monaural auditory evoked potentials are not equivalent to the binaural evoked auditory potentials. Binaural interaction of the early- (0-10 ms), middle- (10-50 ms) and long-latency (50-200 ms) auditory evoked potentials was studied in 17 normal young adults. For the early components, binaural interaction was maximal at 7.35 ms accounting for a reduction of 21% of the amplitude of the binaural evoked potentials. ...

Acoustic stapedial reflexes in healthy neonates: normative data and test-retest reliability.

Science.gov (United States)

Kei, Joseph

2012-01-01

The acoustic stapedial reflex (ASR) test provides useful information about the function of the auditory system. While it is frequently used with adults and children in a clinical setting, its use with young infants is limited. Presently, there are few data for neonates and inadequate research into the test-retest reliability of the ASR test. This study aimed to establish normative data and evaluate the test-retest reliability of the ASR test in healthy neonates. A cross-sectional experimental design was used to establish ASR normative data and assess the test-retest reliability of ASR thresholds obtained from healthy neonates. Sixty-eight full-term neonates with mean chronological age of 2.5 days (SD = 1.8 day), who passed the automated auditory brainstem response, transient evoked otoacoustic emission, and high frequency (1 kHz) tympanometry (HFT) tests. One randomly selected ear from each neonate was tested using TEOAE (transient evoked otoacoustic emission), HFT, and ASR tests using a 1 kHz probe tone. ASR thresholds were elicited by presenting pure tones of 0.5, 2, and 4 kHz and broadband noise (BBN) separately to the test ear in an ipsilateral stimulation mode. The ASR procedure was repeated to acquire retest data within the same testing session. Descriptive statistics, χ2, and analysis of variance with repeated measures tests were used to analyze ASR data. All neonates exhibited ASR when stimulated by tonal stimuli or BBN. The mean ASRTs (acoustic stapedial reflex thresholds) for the 0.5, 2, and 4 kHz tones were 81.6 ± 7.9, 71.3 ± 7.9, and 65.4 ± 8.7 dB HL, respectively. The mean ASRT for the BBN was estimated to be smaller than 57.2 dB HL, given the limitation of the equipment. The 95th percentiles of the ASRT were 95, 85, 80, and 75 dB HL for the 0.5, 2, and 4 kHz and BBN, respectively. The test-retest reliability of the ASR test for all stimuli was high, with no significant difference in mean ASRTs across the test and retest conditions. Test

Diffusion tractography of the subcortical auditory system in a postmortem human brain

OpenAIRE

Sitek, Kevin

2017-01-01

The subcortical auditory system is challenging to identify with standard human brain imaging techniques: MRI signal decreases toward the center of the brain as well as at higher resolution, both of which are necessary for imaging small brainstem auditory structures.Using high-resolution diffusion-weighted MRI, we asked:Can we identify auditory structures and connections in high-resolution ex vivo images?Which structures and connections can be mapped in vivo?

Auditory- and visual-evoked potentials in Mexican infants are not affected by maternal supplementation with 400 mg/d docosahexaenoic acid in the second half of pregnancy.

Science.gov (United States)

Stein, Aryeh D; Wang, Meng; Rivera, Juan A; Martorell, Reynaldo; Ramakrishnan, Usha

2012-08-01

The evidence relating prenatal supplementation with DHA to offspring neurological development is limited. We investigated the effect of prenatal DHA supplementation on infant brainstem auditory-evoked responses and visual- evoked potentials in a double-blind, randomized controlled trial in Cuernavaca, Mexico. Pregnant women were supplemented daily with 400 mg DHA or placebo from gestation wk 18-22 through delivery. DHA and placebo groups did not differ in maternal characteristics at randomization or infant characteristics at birth. Brainstem auditory-evoked responses were measured at 1 and 3 mo in 749 and 664 infants, respectively, and visual-evoked potentials were measured at 3 and 6 mo in 679 and 817 infants, respectively. Left-right brainstem auditory-evoked potentials were moderately correlated (range, 0.26-0.43; all P right visual-evoked potentials were strongly correlated (range, 0.79-0.94; all P 0.10). We conclude that DHA supplementation during pregnancy did not influence brainstem auditory-evoked responses at 1 and 3 mo or visual-evoked potentials at 3 and 6 mo.

A Telehealth System for Remote Auditory Evoked Potential Monitoring

OpenAIRE

Millan, Jorge; Yunda, Leonardo

2013-01-01

A portable, Internet-based EEG/Auditory Evoked Potential (AEP) monitoring system was developed for remote electrophysiological studies during sleep. The system records EEG/AEP simultaneously at the subject?s home for increased comfort and flexibility. The system provides simultaneous recording and remote viewing of EEG, EMG and EOG waves and allows on-line averaging of auditory evoked potentials. The design allows the recording of all major AEP components (brainstem, middle and late latency E...

Dopamine in the Auditory Brainstem and Midbrain: Co-localization with Amino Acid Neurotransmitters and Gene Expression following Cochlear Trauma

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Avril Genene eHolt

2015-07-01

Full Text Available Dopamine (DA modulates the effects of amino acid neurotransmitters, including GABA and glutamate, in motor, visual, olfactory and reward systems (Hnasko et al., 2010; Stuber et al., 2010; Hnasko and Edwards, 2012. The results suggest that DA may play a similar modulatory role in the auditory pathways. Previous studies have shown that deafness results in decreased GABA release, changes in excitatory neurotransmitter levels, and increased spontaneous neuronal activity within brainstem regions related to auditory function. Modulation of the expression and localization of tyrosine hydroxylase (TH; the rate limiting enzyme in the production of DA in the IC following cochlear trauma has been previously reported (Tong et al., 2005. In the current study the possibility of co-localization of TH with amino acid neurotransmitters (AANs was examined. Changes in the gene expression of TH were compared with changes in the gene expression of markers for AANs in the cochlear nucleus (CN and IC to determine whether those deafness related changes occur concurrently. The results indicate that bilateral cochlear ablation significantly reduced TH gene expression in the CN after two months while in the IC the reduction in TH was observed at both three days and two months following ablation. Furthermore, in the CN, glycine transporter 2 (GlyT2 and the GABA transporter (GABAtp were also significantly reduced only after two months. However, in the IC, DA receptor 1 (DRDA1, vesicular glutamate transporters 2 and 3 (vGluT2, vGluT3, GABAtp and GAD67 were reduced in expression both at the three day and two month time points. A close relationship between the distribution of TH and several of the AANs was determined in both the CN and the IC. In addition, GlyT2 and vGluT3 each co-localized with TH within IC somata and dendrites. Therefore, the results of the current study suggest that DA is spatially well positioned to influence the effects of AANs on auditory neurons.

Absence of both auditory evoked potentials and auditory percepts dependent on timing cues.

Science.gov (United States)

Starr, A; McPherson, D; Patterson, J; Don, M; Luxford, W; Shannon, R; Sininger, Y; Tonakawa, L; Waring, M

1991-06-01

An 11-yr-old girl had an absence of sensory components of auditory evoked potentials (brainstem, middle and long-latency) to click and tone burst stimuli that she could clearly hear. Psychoacoustic tests revealed a marked impairment of those auditory perceptions dependent on temporal cues, that is, lateralization of binaural clicks, change of binaural masked threshold with changes in signal phase, binaural beats, detection of paired monaural clicks, monaural detection of a silent gap in a sound, and monaural threshold elevation for short duration tones. In contrast, auditory functions reflecting intensity or frequency discriminations (difference limens) were only minimally impaired. Pure tone audiometry showed a moderate (50 dB) bilateral hearing loss with a disproportionate severe loss of word intelligibility. Those auditory evoked potentials that were preserved included (1) cochlear microphonics reflecting hair cell activity; (2) cortical sustained potentials reflecting processing of slowly changing signals; and (3) long-latency cognitive components (P300, processing negativity) reflecting endogenous auditory cognitive processes. Both the evoked potential and perceptual deficits are attributed to changes in temporal encoding of acoustic signals perhaps occurring at the synapse between hair cell and eighth nerve dendrites. The results from this patient are discussed in relation to previously published cases with absent auditory evoked potentials and preserved hearing.

The role of eABR with intracochlear test electrode in decision making between cochlear and brainstem implants: preliminary results.

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Cinar, Betul Cicek; Yarali, Mehmet; Atay, Gamze; Bajin, Munir Demir; Sennaroglu, Gonca; Sennaroglu, Levent

2017-09-01

The objective of the study was to discuss the findings of intraoperative electrically evoked auditory brainstem response (eABR) test results with a recently designed intracochlear test electrode (ITE) in terms of their relation to decisions of cochlear or auditory brainstem implantation. This clinical study was conducted in Hacettepe University, Department of Otolaryngology, Head and Neck Surgery and Department of Audiology. Subjects were selected from inner ear malformation (IEM) database. Eleven subjects with profound sensorineural hearing loss were included in the current study with age range from 1 year 3 months to 4 years 3 months for children with prelingual hearing loss. There was only one 42-year-old post-lingual subject. eABR was recorded with an ITE and intraoperatively with an original cochlear implant (CI) electrode in 11 cases with different IEMs. Findings of eABR with ITE and their relation to the decision for CI or auditory brainstem implant (ABI) are discussed. Positive eABR test results were found to be dependent on close to normal cochlear structures and auditory nerve. The probability of positive result decreases with increasing degree of malformation severity. The prediction value of eABR via ITE on decision for hearing restoration was found to be questionable in this study. The results of eABR with ITE have predictive value on what we will get with the actual CI electrode. ITE appears to stimulate the cochlea like an actual CI. If the eABR is positive, the results are reliable. However, if eABR is negative, the results should be evaluated with preoperative audiological testing and MRI findings.

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.

Testing auditory sensitivity in the great cormorant (Phalacrocorax carbo sinensis)

DEFF Research Database (Denmark)

Maxwell, Alyssa; Hansen, Kirstin Anderson; Larsen, Ole Næsbye

2016-01-01

Psychoacoustic and electrophysiological methods were used to measure the in-air hearing sensitivity of the great cormorant (Phalacrocorax carbo sinensis). One individual was used to determine the behavioral thresholds, which was then compared to previously collected data on the auditory brainstem...

Auditory Neural Prostheses – A Window to the Future

Directory of Open Access Journals (Sweden)

Mohan Kameshwaran

2015-06-01

Full Text Available Hearing loss is one of the commonest congenital anomalies to affect children world-over. The incidence of congenital hearing loss is more pronounced in developing countries like the Indian sub-continent, especially with the problems of consanguinity. Hearing loss is a double tragedy, as it leads to not only deafness but also language deprivation. However, hearing loss is the only truly remediable handicap, due to remarkable advances in biomedical engineering and surgical techniques. Auditory neural prostheses help to augment or restore hearing by integration of an external circuitry with the peripheral hearing apparatus and the central circuitry of the brain. A cochlear implant (CI is a surgically implantable device that helps restore hearing in patients with severe-profound hearing loss, unresponsive to amplification by conventional hearing aids. CIs are electronic devices designed to detect mechanical sound energy and convert it into electrical signals that can be delivered to the coch­lear nerve, bypassing the damaged hair cells of the coch­lea. The only true prerequisite is an intact auditory nerve. The emphasis is on implantation as early as possible to maximize speech understanding and perception. Bilateral CI has significant benefits which include improved speech perception in noisy environments and improved sound localization. Presently, the indications for CI have widened and these expanded indications for implantation are related to age, additional handicaps, residual hearing, and special etiologies of deafness. Combined electric and acoustic stimulation (EAS / hybrid device is designed for individuals with binaural low-frequency hearing and severe-to-profound high-frequency hearing loss. Auditory brainstem implantation (ABI is a safe and effective means of hearing rehabilitation in patients with retrocochlear disorders, such as neurofibromatosis type 2 (NF2 or congenital cochlear nerve aplasia, wherein the cochlear nerve is damaged

Normative data for a computer-assisted version of the auditory three-consonant Brown-Peterson paradigm in the elderly French-Quebec population.

Science.gov (United States)

Callahan, Brandy L; Belleville, Sylvie; Ferland, Guylaine; Potvin, Olivier; Tremblay, Marie-Pier; Hudon, Carol; Macoir, Joël

2014-01-01

The Brown-Peterson task is used to assess verbal short-term memory as well as divided attention. In its auditory three-consonant version, trigrams are presented to participants who must recall the items in correct order after variable delays, during which an interference task is performed. The present study aimed to establish normative data for this test in the elderly French-Quebec population based on cross-sectional data from a retrospective, multi-center convenience sample. A total of 595 elderly native French-speakers from the province of Quebec performed the Memoria version of the auditory three-consonant Brown-Peterson test. For both series and item-by-item scoring methods, age, education, and, in most cases, recall after a 0-second interval were found to be significantly associated with recall performance after 10-second, 20-second, and 30-second interference intervals. Based on regression model results, equations to calculate Z scores are presented for the 10-second, 20-second and 30-second intervals and for each scoring method to allow estimation of expected performance based on participants' individual characteristics. As an important ceiling effect was observed at the 0-second interval, norms for this interference interval are presented in percentiles.

Effects of auditory training in individuals with high-frequency hearing loss

Directory of Open Access Journals (Sweden)

Renata Beatriz Fernandes Santos

2014-01-01

Full Text Available OBJECTIVE: To determine the effects of a formal auditory training program on the behavioral, electrophysiological and subjective aspects of auditory function in individuals with bilateral high-frequency hearing loss. METHOD: A prospective study of seven individuals aged 46 to 57 years with symmetric, moderate high-frequency hearing loss ranging from 3 to 8 kHz was conducted. Evaluations of auditory processing (sound location, verbal and non-verbal sequential memory tests, the speech-in-noise test, the staggered spondaic word test, synthetic sentence identification with competitive ipsilateral and contralateral competitive messages, random gap detection and the standard duration test, auditory brainstem response and long-latency potentials and the administration of the Abbreviated Profile of Hearing Aid Benefit questionnaire were performed in a sound booth before and immediately after formal auditory training. RESULTS: All of the participants demonstrated abnormal pre-training long-latency characteristics (abnormal latency or absence of the P3 component and these abnormal characteristics were maintained in six of the seven individuals at the post-training evaluation. No significant differences were found between ears in the quantitative analysis of auditory brainstem responses or long-latency potentials. However, the subjects demonstrated improvements on all behavioral tests. For the questionnaire, the difference on the background noise subscale achieved statistical significance. CONCLUSION: Auditory training in adults with high-frequency hearing loss led to improvements in figure-background hearing skills for verbal sounds, temporal ordination and resolution, and communication in noisy environments. Electrophysiological changes were also observed because, after the training, some long latency components that were absent pre-training were observed during the re-evaluation.

AULA-Advanced Virtual Reality Tool for the Assessment of Attention: Normative Study in Spain.

Science.gov (United States)

Iriarte, Yahaira; Diaz-Orueta, Unai; Cueto, Eduardo; Irazustabarrena, Paula; Banterla, Flavio; Climent, Gema

2016-06-01

The present study describes the obtention of normative data for the AULA test, a virtual reality tool designed to evaluate attention problems, especially in children and adolescents. The normative sample comprised 1,272 participants (48.2% female) with an age range from 6 to 16 years (M = 10.25, SD = 2.83). The AULA test administered to them shows both visual and auditory stimuli, while randomized distractors of ecological nature appear progressively. Variables provided by AULA were clustered in different categories for their posterior analysis. Differences by age and gender were analyzed, resulting in 14 groups, 7 per sex group. Differences between visual and auditory attention were also obtained. Obtained normative data are relevant for the use of AULA for evaluating attention in Spanish children and adolescents in a more ecological way. Further studies will be needed to determine sensitivity and specificity of AULA to measure attention in different clinical populations. (J. of Att. Dis. 2016; 20(6) 542-568). © The Author(s) 2012.

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.

The relationship of age, gender, and IQ with the brainstem and thalamus in healthy children and adolescents: a magnetic resonance imaging volumetric study.

Science.gov (United States)

Xie, Yuhuan; Chen, Yian Ann; De Bellis, Michael D

2012-03-01

In healthy children, there is a paucity of information on the growth of the brainstem and thalamus measured anatomically magnetic resonance imaging. The relations of age, gender, and age by gender with brainstem and thalamus volumes were analyzed from magnetic resonance brain images of 122 healthy children and adolescents (62 males, 60 females; ages 4 to 17). Results showed that age is a significant predictor of brainstem and thalamus volumes. The volume of the brainstem increases with age, while thalamus volume declines with age. The volume of the right thalamus is significantly larger than that of the left in both genders, with greater rightward asymmetry and greater thalamus to grey matter ratio in females. Males have larger brainstems, but these differences are not significant when covarying for cerebral volume. Larger thalami were associated with higher Verbal IQ. These normative pediatric data are of value to researchers who study these regions in neurodevelopmental disorders.

A Case of Generalized Auditory Agnosia with Unilateral Subcortical Brain Lesion

Science.gov (United States)

Suh, Hyee; Kim, Soo Yeon; Kim, Sook Hee; Chang, Jae Hyeok; Shin, Yong Beom; Ko, Hyun-Yoon

2012-01-01

The mechanisms and functional anatomy underlying the early stages of speech perception are still not well understood. Auditory agnosia is a deficit of auditory object processing defined as a disability to recognize spoken languages and/or nonverbal environmental sounds and music despite adequate hearing while spontaneous speech, reading and writing are preserved. Usually, either the bilateral or unilateral temporal lobe, especially the transverse gyral lesions, are responsible for auditory agnosia. Subcortical lesions without cortical damage rarely causes auditory agnosia. We present a 73-year-old right-handed male with generalized auditory agnosia caused by a unilateral subcortical lesion. He was not able to repeat or dictate but to perform fluent and comprehensible speech. He could understand and read written words and phrases. His auditory brainstem evoked potential and audiometry were intact. This case suggested that the subcortical lesion involving unilateral acoustic radiation could cause generalized auditory agnosia. PMID:23342322

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.

Biological impact of music and software-based auditory training

Science.gov (United States)

Kraus, Nina

2012-01-01

Auditory-based communication skills are developed at a young age and are maintained throughout our lives. However, some individuals – both young and old – encounter difficulties in achieving or maintaining communication proficiency. Biological signals arising from hearing sounds relate to real-life communication skills such as listening to speech in noisy environments and reading, pointing to an intersection between hearing and cognition. Musical experience, amplification, and software-based training can improve these biological signals. These findings of biological plasticity, in a variety of subject populations, relate to attention and auditory memory, and represent an integrated auditory system influenced by both sensation and cognition. Learning outcomes The reader will (1) understand that the auditory system is malleable to experience and training, (2) learn the ingredients necessary for auditory learning to successfully be applied to communication, (3) learn that the auditory brainstem response to complex sounds (cABR) is a window into the integrated auditory system, and (4) see examples of how cABR can be used to track the outcome of experience and training. PMID:22789822

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.

[A case of transient auditory agnosia and schizophrenia].

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Kanzaki, Jin; Harada, Tatsuhiko; Kanzaki, Sho

2011-03-01

We report a case of transient functional auditory agnosia and schizophrenia and discuss their relationship. A 30-year-old woman with schizophrenia reporting bilateral hearing loss was found in history taking to be able to hear but could neither understand speech nor discriminate among environmental sounds. Audiometry clarified normal but low speech discrimination. Otoacoustic emission and auditory brainstem response were normal. Magnetic resonance imaging (MRI) elsewhere evidenced no abnormal findings. We assumed that taking care of her grandparents who had been discharged from the hospital had unduly stressed her, and her condition improved shortly after she stopped caring for them, returned home and started taking a minor tranquilizer.

Auditory evoked functions in ground crew working in high noise environment of Mumbai airport.

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Thakur, L; Anand, J P; Banerjee, P K

2004-10-01

The continuous exposure to the relatively high level of noise in the surroundings of an airport is likely to affect the central pathway of the auditory system as well as the cognitive functions of the people working in that environment. The Brainstem Auditory Evoked Responses (BAER), Mid Latency Response (MLR) and P300 response of the ground crew employees working in Mumbai airport were studied to evaluate the effects of continuous exposure to high level of noise of the surroundings of the airport on these responses. BAER, P300 and MLR were recorded by using a Nicolet Compact-4 (USA) instrument. Audiometry was also monitored with the help of GSI-16 Audiometer. There was a significant increase in the peak III latency of the BAER in the subjects exposed to noise compared to controls with no change in their P300 values. The exposed group showed hearing loss at different frequencies. The exposure to the high level of noise caused a considerable decline in the auditory conduction upto the level of the brainstem with no significant change in conduction in the midbrain, subcortical areas, auditory cortex and associated areas. There was also no significant change in cognitive function as measured by P300 response.

Auditory processing in the brainstem and audiovisual integration in humans studied with fMRI

NARCIS (Netherlands)

Slabu, Lavinia Mihaela

2008-01-01

Functional magnetic resonance imaging (fMRI) is a powerful technique because of the high spatial resolution and the noninvasiveness. The applications of the fMRI to the auditory pathway remain a challenge due to the intense acoustic scanner noise of approximately 110 dB SPL. The auditory system

Subcortical pathways: Towards a better understanding of auditory disorders.

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Felix, Richard A; Gourévitch, Boris; Portfors, Christine V

2018-05-01

Hearing loss is a significant problem that affects at least 15% of the population. This percentage, however, is likely significantly higher because of a variety of auditory disorders that are not identifiable through traditional tests of peripheral hearing ability. In these disorders, individuals have difficulty understanding speech, particularly in noisy environments, even though the sounds are loud enough to hear. The underlying mechanisms leading to such deficits are not well understood. To enable the development of suitable treatments to alleviate or prevent such disorders, the affected processing pathways must be identified. Historically, mechanisms underlying speech processing have been thought to be a property of the auditory cortex and thus the study of auditory disorders has largely focused on cortical impairments and/or cognitive processes. As we review here, however, there is strong evidence to suggest that, in fact, deficits in subcortical pathways play a significant role in auditory disorders. In this review, we highlight the role of the auditory brainstem and midbrain in processing complex sounds and discuss how deficits in these regions may contribute to auditory dysfunction. We discuss current research with animal models of human hearing and then consider human studies that implicate impairments in subcortical processing that may contribute to auditory disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

Searching for the optimal stimulus eliciting auditory brainstem responses in humans

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Fobel, Oliver; Dau, Torsten

2004-01-01

-chirp, was based on estimates of human basilar membrane (BM) group delays derived from stimulus-frequency otoacoustic emissions (SFOAE) at a sound pressure level of 40 dB [Shera and Guinan, in Recent Developments in Auditory Mechanics (2000)]. The other chirp, referred to as the A-chirp, was derived from latency...

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.

Electrophysiological assessment of auditory processing disorder in children with non-syndromic cleft lip and/or palate.

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Ma, Xiaoran; McPherson, Bradley; Ma, Lian

2016-01-01

Cleft lip and/or palate is a common congenital craniofacial malformation found worldwide. A frequently associated disorder is conductive hearing loss, and this disorder has been thoroughly investigated in children with non-syndromic cleft lip and/or palate (NSCL/P). However, analysis of auditory processing function is rarely reported for this population, although this issue should not be ignored since abnormal auditory cortical structures have been found in populations with cleft disorders. The present study utilized electrophysiological tests to assess the auditory status of a large group of children with NSCL/P, and investigated whether this group had less robust central auditory processing abilities compared to craniofacially normal children. 146 children with NSCL/P who had normal peripheral hearing thresholds, and 60 craniofacially normal children aged from 6 to 15 years, were recruited. Electrophysiological tests, including auditory brainstem response (ABR), P1-N1-P2 complex, and P300 component recording, were conducted. ABR and N1 wave latencies were significantly prolonged in children with NSCL/P. An atypical developmental trend was found for long latency potentials in children with cleft compared to control group children. Children with unilateral cleft lip and palate showed a greater level of abnormal results compared with other cleft subgroups, whereas the cleft lip subgroup had the most robust responses for all tests. Children with NSCL/P may have slower than normal neural transmission times between the peripheral auditory nerve and brainstem. Possible delayed development of myelination and synaptogenesis may also influence auditory processing function in this population. Present research outcomes were consistent with previous, smaller sample size, electrophysiological studies on infants and children with cleft lip/palate disorders. In view of the these findings, and reports of educational disadvantage associated with cleft disorders, further research

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

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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).

Age and education adjusted normative data and discriminative validity for Rey's Auditory Verbal Learning Test in the elderly Greek population.

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Messinis, Lambros; Nasios, Grigorios; Mougias, Antonios; Politis, Antonis; Zampakis, Petros; Tsiamaki, Eirini; Malefaki, Sonia; Gourzis, Phillipos; Papathanasopoulos, Panagiotis

2016-01-01

Rey's Auditory Verbal Learning Test (RAVLT) is a widely used neuropsychological test to assess episodic memory. In the present study we sought to establish normative and discriminative validity data for the RAVLT in the elderly population using previously adapted learning lists for the Greek adult population. We administered the test to 258 cognitively healthy elderly participants, aged 60-89 years, and two patient groups (192 with amnestic mild cognitive impairment, aMCI, and 65 with Alzheimer's disease, AD). From the statistical analyses, we found that age and education contributed significantly to most trials of the RAVLT, whereas the influence of gender was not significant. Younger elderly participants with higher education outperformed the older elderly with lower education levels. Moreover, both clinical groups performed significantly worse on most RAVLT trials and composite measures than matched cognitively healthy controls. Furthermore, the AD group performed more poorly than the aMCI group on most RAVLT variables. Receiver operating characteristic (ROC) analysis was used to examine the utility of the RAVLT trials to discriminate cognitively healthy controls from aMCI and AD patients. Area under the curve (AUC), an index of effect size, showed that most of the RAVLT measures (individual and composite) included in this study adequately differentiated between the performance of healthy elders and aMCI/AD patients. We also provide cutoff scores in discriminating cognitively healthy controls from aMCI and AD patients, based on the sensitivity and specificity of the prescribed scores. Moreover, we present age- and education-specific normative data for individual and composite scores for the Greek adapted RAVLT in elderly subjects aged between 60 and 89 years for use in clinical and research settings.

VGLUT3 does not synergize GABA/glycine release during functional refinement of an inhibitory auditory circuit

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Daniel T Case

2014-11-01

Full Text Available The vesicular glutamate transporter VGLUT3 is expressed at several locations not normally associated with glutamate release. Although the function of this protein remains generally elusive, when expressed in non-glutamatergic synaptic terminals, VGLUT3 can not only allow glutamate co-transmission but also synergize the action of non-glutamate vesicular transporters. Interestingly, in the immature glycinergic projection between the medial nucleus of the trapezoid body (MNTB and the lateral superior olive (LSO of auditory brainstem, the transient early expression of VGLUT3 is required for normal developmental refinement. It has however been unknown whether the primary function of VGLUT3 in development of these inhibitory synapses is to enable glutamate release or to promote loading of inhibitory neurotransmitter through vesicular synergy. Using tissue from young mice in which Vglut3 had been genetically deleted, we evaluated inhibitory neurotransmission in the MNTB-LSO pathway. Our results show, in contrast to what has been seen at adult synapses, that VGLUT3 expression has little or no effect on vesicular synergy at the immature glycinergic synapse of brainstem. This finding supports the model that the primary function of increased VGLUT3 expression in the immature auditory brainstem is to enable glutamate release in a developing inhibitory circuit.

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

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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

Acoustic Trauma Changes the Parvalbumin-Positive Neurons in Rat Auditory Cortex

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Congli Liu

2018-01-01

Full Text Available Acoustic trauma is being reported to damage the auditory periphery and central system, and the compromised cortical inhibition is involved in auditory disorders, such as hyperacusis and tinnitus. Parvalbumin-containing neurons (PV neurons, a subset of GABAergic neurons, greatly shape and synchronize neural network activities. However, the change of PV neurons following acoustic trauma remains to be elucidated. The present study investigated how auditory cortical PV neurons change following unilateral 1 hour noise exposure (left ear, one octave band noise centered at 16 kHz, 116 dB SPL. Noise exposure elevated the auditory brainstem response threshold of the exposed ear when examined 7 days later. More detectable PV neurons were observed in both sides of the auditory cortex of noise-exposed rats when compared to control. The detectable PV neurons of the left auditory cortex (ipsilateral to the exposed ear to noise exposure outnumbered those of the right auditory cortex (contralateral to the exposed ear. Quantification of Western blotted bands revealed higher expression level of PV protein in the left cortex. These findings of more active PV neurons in noise-exposed rats suggested that a compensatory mechanism might be initiated to maintain a stable state of the brain.

A brainstem anosognosia of hemiparesis

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Kazuo Abe

2009-10-01

Full Text Available A woman had anosognosia for hemiplegia as a manifestation of brainstem infarction. She had no mental or neuropsychological disturbances, and had involvement of the brainstem in the frontal/parietal-subcortical circuits to the right cerebral hemisphere. Brainstem lesions that disrupt frontal/parietal-subcortical areas may affect anosognosia for hemiplegia.

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

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...

[Effect of Electroacupuncture on Expression of Catechol-O-methyltransferase in the Inferior Colliculus and Auditory Cortex in Age-related Hearing Loss Guinea Pigs].

Science.gov (United States)

Liu, Shu-Yun; Deng, Li-Qiang; Yang, Ye; Yin, Ze-Deng

2017-04-25

To observe the expression of catechol-O-methyltransferase (COMT) in inferior colliculus and auditory cortex of guinea pigs with age-related hearing loss(AHL) induced by D-galactose, so as to explore the possible mechanism of electroacupuncture(EA) underlying preventing AHL. Thirty 3-month-old guinea pigs were randomly divided into control group, model group and EA group( n =10 in each group), and ten 18-month-old guinea pigs were allocated as elderly group. The AHL model was established by subcutaneous injection of D-galactose. EA was applied to bilateral "Yifeng"(SJ 17) and "Tinggong"(SI 19) for 15 min in the EA group while modeling, once daily for 6 weeks. After treatment, the latency of auditory brainstem response(ABR) Ⅲ wave was measured by a brain-stem evoked potentiometer. The expressions of COMT in the inferior colliculus and auditory cortex were detected by Western blot. Compared with the control group, the latencies of ABR Ⅲ wave were significantly prolonged and the expressions of COMT in the inferior colliculus and auditory cortex were significantly decreased in the model group and the elderly group( P guinea pigs, which may contribute to its effect in up-regulating the expression of COMT in the inferior colliculus and auditory cortex.

The auditory enhancement effect is not reflected in the 80-Hz auditory steady-state response.

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Carcagno, Samuele; Plack, Christopher J; Portron, Arthur; Semal, Catherine; Demany, Laurent

2014-08-01

The perceptual salience of a target tone presented in a multitone background is increased by the presentation of a precursor sound consisting of the multitone background alone. It has been proposed that this "enhancement" phenomenon results from an effective amplification of the neural response to the target tone. In this study, we tested this hypothesis in humans, by comparing the auditory steady-state response (ASSR) to a target tone that was enhanced by a precursor sound with the ASSR to a target tone that was not enhanced. In order to record neural responses originating in the brainstem, the ASSR was elicited by amplitude modulating the target tone at a frequency close to 80 Hz. The results did not show evidence of an amplified neural response to enhanced tones. In a control condition, we measured the ASSR to a target tone that, instead of being perceptually enhanced by a precursor sound, was acoustically increased in level. This level increase matched the magnitude of enhancement estimated psychophysically with a forward masking paradigm in a previous experimental phase. We found that the ASSR to the tone acoustically increased in level was significantly greater than the ASSR to the tone enhanced by the precursor sound. Overall, our results suggest that the enhancement effect cannot be explained by an amplified neural response at the level of the brainstem. However, an alternative possibility is that brainstem neurons with enhanced responses do not contribute to the scalp-recorded ASSR.

Enhanced brainstem and cortical evoked response amplitudes: single-trial covariance analysis.

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Galbraith, G C

2001-06-01

The purpose of the present study was to develop analytic procedures that improve the definition of sensory evoked response components. Such procedures could benefit all recordings but would especially benefit difficult recordings where many trials are contaminated by muscle and movement artifacts. First, cross-correlation and latency adjustment analyses were applied to the human brainstem frequency-following response and cortical auditory evoked response recorded on the same trials. Lagged cross-correlation functions were computed, for each of 17 subjects, between single-trial data and templates consisting of the sinusoid stimulus waveform for the brainstem response and the subject's own smoothed averaged evoked response P2 component for the cortical response. Trials were considered in the analysis only if the maximum correlation-squared (r2) exceeded .5 (negatively correlated trials were thus included). Identical correlation coefficients may be based on signals with quite different amplitudes, but it is possible to assess amplitude by the nonnormalized covariance function. Next, an algorithm is applied in which each trial with negative covariance is matched to a trial with similar, but positive, covariance and these matched-trial pairs are deleted. When an evoked response signal is present in the data, the majority of trials positively correlate with the template. Thus, a residual of positively correlated trials remains after matched covariance trials are deleted. When these residual trials are averaged, the resulting brainstem and cortical responses show greatly enhanced amplitudes. This result supports the utility of this analysis technique in clarifying and assessing evoked response signals.

The combined effects of forward masking by noise and high click rate on monaural and binaural human auditory nerve and brainstem potentials.

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Pratt, Hillel; Polyakov, Andrey; Bleich, Naomi; Mittelman, Naomi

2004-07-01

To study effects of forward masking and rapid stimulation on human monaurally- and binaurally-evoked brainstem potentials and suggest their relation to synaptic fatigue and recovery and to neuronal action potential refractoriness. Auditory brainstem evoked potentials (ABEPs) were recorded from 12 normally- and symmetrically hearing adults, in response to each click (50 dB nHL, condensation and rarefaction) in a train of nine, with an inter-click interval of 11 ms, that followed a white noise burst of 100 ms duration (50 dB nHL). Sequences of white noise and click train were repeated at a rate of 2.89 s(-1). The interval between noise and first click in the train was 2, 11, 22, 44, 66 or 88 ms in different runs. ABEPs were averaged (8000 repetitions) using a dwell time of 25 micros/address/channel. The binaural interaction components (BICs) of ABEPs were derived and the single, centrally located equivalent dipoles of ABEP waves I and V and of the BIC major wave were estimated. The latencies of dipoles I and V of ABEP, their inter-dipole interval and the dipole magnitude of component V were significantly affected by the interval between noise and clicks and by the serial position of the click in the train. The latency and dipole magnitude of the major BIC component were significantly affected by the interval between noise and clicks. Interval from noise and the click's serial position in the train interacted to affect dipole V latency, dipole V magnitude, BIC latencies and the V-I inter-dipole latency difference. Most of the effects were fully apparent by the first few clicks in the train, and the trend (increase or decrease) was affected by the interval between noise and clicks. The changes in latency and magnitude of ABEP and BIC components with advancing position in the click train and the interactions of click position in the train with the intervals from noise indicate an interaction of fatigue and recovery, compatible with synaptic depletion and replenishing

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.

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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.

Developmental trends in auditory processing can provide early predictions of language acquisition in young infants.

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Chonchaiya, Weerasak; Tardif, Twila; Mai, Xiaoqin; Xu, Lin; Li, Mingyan; Kaciroti, Niko; Kileny, Paul R; Shao, Jie; Lozoff, Betsy

2013-03-01

Auditory processing capabilities at the subcortical level have been hypothesized to impact an individual's development of both language and reading abilities. The present study examined whether auditory processing capabilities relate to language development in healthy 9-month-old infants. Participants were 71 infants (31 boys and 40 girls) with both Auditory Brainstem Response (ABR) and language assessments. At 6 weeks and/or 9 months of age, the infants underwent ABR testing using both a standard hearing screening protocol with 30 dB clicks and a second protocol using click pairs separated by 8, 16, and 64-ms intervals presented at 80 dB. We evaluated the effects of interval duration on ABR latency and amplitude elicited by the second click. At 9 months, language development was assessed via parent report on the Chinese Communicative Development Inventory - Putonghua version (CCDI-P). Wave V latency z-scores of the 64-ms condition at 6 weeks showed strong direct relationships with Wave V latency in the same condition at 9 months. More importantly, shorter Wave V latencies at 9 months showed strong relationships with the CCDI-P composite consisting of phrases understood, gestures, and words produced. Likewise, infants who had greater decreases in Wave V latencies from 6 weeks to 9 months had higher CCDI-P composite scores. Females had higher language development scores and shorter Wave V latencies at both ages than males. Interestingly, when the ABR Wave V latencies at both ages were taken into account, the direct effects of gender on language disappeared. In conclusion, these results support the importance of low-level auditory processing capabilities for early language acquisition in a population of typically developing young infants. Moreover, the auditory brainstem response in this paradigm shows promise as an electrophysiological marker to predict individual differences in language development in young children. © 2012 Blackwell Publishing Ltd.

Normative Power

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's normative power than any other academic journal, including a special issue on "What Kind of Power?" in 2006. As the leading journal in the debate, this special issue brings together seven normative power articles published in JEPP since the 2006 special issue, together with Ian Manners' ‘Normative power......The social sciences have many different understandings of ‘normative power', but in European Union (EU) studies normative power has three particular meanings. The first meaning of normative power is its emphasis on normative theory, that is, how we judge and justify truth claims in social science...... effects of EU relations with the world in areas ranging from inter-regional relations, through traditional diplomacy, to environmental politics. Research areas of particular interest include the study of the interplay between physical, material and normative forms of power, as well as the constitutive...

Cochlear injury and adaptive plasticity of the auditory cortex

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ANNA R. eFETONI

2015-02-01

Full Text Available Growing evidence suggests that cochlear stressors as noise exposure and aging can induce homeostatic/maladaptive changes in the central auditory system from the brainstem to the cortex. Studies centered on such changes have revealed several mechanisms that operate in the context of sensory disruption after insult (noise trauma, drug- or age-related injury. The oxidative stress is central to current theories of induced sensory neural hearing loss and aging, and interventions to attenuate the hearing loss are based on antioxidant agent. The present review addresses the recent literature on the alterations in hair cells and spiral ganglion neurons due to noise-induced oxidative stress in the cochlea, as well on the impact of cochlear damage on the auditory cortex neurons. The emerging image emphasizes that noise-induced deafferentation and upward spread of cochlear damage is associated with the altered dendritic architecture of auditory pyramidal neurons. The cortical modifications may be reversed by treatment with antioxidants counteracting the cochlear redox imbalance. These findings open new therapeutic approaches to treat the functional consequences of the cortical reorganization following cochlear damage.

Effects of exposure to 2100 MHz GSM-like radiofrequency electromagnetic field on auditory system of rats

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Metin Çeliker

Full Text Available Abstract Introduction: The use of mobile phones has become widespread in recent years. Although beneficial from the communication viewpoint, the electromagnetic fields generated by mobile phones may cause unwanted biological changes in the human body. Objective: In this study, we aimed to evaluate the effects of 2100 MHz Global System for Mobile communication (GSM-like electromagnetic field, generated by an electromagnetic fields generator, on the auditory system of rats by using electrophysiological, histopathologic and immunohistochemical methods. Methods: Fourteen adult Wistar albino rats were included in the study. The rats were divided randomly into two groups of seven rats each. The study group was exposed continuously for 30 days to a 2100 MHz electromagnetic fields with a signal level (power of 5.4 dBm (3.47 mW to simulate the talk mode on a mobile phone. The control group was not exposed to the aforementioned electromagnetic fields. After 30 days, the Auditory Brainstem Responses of both groups were recorded and the rats were sacrificed. The cochlear nuclei were evaluated by histopathologic and immunohistochemical methods. Results: The Auditory Brainstem Responses records of the two groups did not differ significantly. The histopathologic analysis showed increased degeneration signs in the study group (p = 0.007. In addition, immunohistochemical analysis revealed increased apoptotic index in the study group compared to that in the control group (p = 0.002. Conclusion: The results support that long-term exposure to a GSM-like 2100 MHz electromagnetic fields causes an increase in neuronal degeneration and apoptosis in the auditory system.

Correlation of augmented startle reflex with brainstem electrophysiological responses in Tay-Sachs disease.

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Nakamura, Sadao; Saito, Yoshiaki; Ishiyama, Akihiko; Sugai, Kenji; Iso, Takashi; Inagaki, Masumi; Sasaki, Masayuki

2015-01-01

To clarify the evolution of an augmented startle reflex in Tay-Sachs disease and compare the temporal relationship between this reflex and brainstem evoked potentials. Clinical and electrophysiological data from 3 patients with Tay-Sachs disease were retrospectively collected. The augmented startle reflex appeared between the age of 3 and 17 months and disappeared between the age of 4 and 6 years. Analysis of brainstem auditory evoked potentials revealed that poor segregation of peak I, but not peak III, coincided with the disappearance of the augmented startle reflex. A blink reflex with markedly high amplitude was observed in a patient with an augmented startle reflex. The correlation between the augmented startle reflex and the preservation of peak I but not peak III supports the theory that the superior olivary nucleus is dispensable for this reflex. The blink reflex with high amplitudes may represent augmented excitability of reticular formation at the pontine tegmentum in Tay-Sachs disease, where the pattern generators for the augmented startle and blink reflexes may functionally overlap. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Aging effects on the binaural interaction component of the auditory brainstem response in the Mongolian gerbil: Effects of interaural time and level differences.

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Laumen, Geneviève; Tollin, Daniel J; Beutelmann, Rainer; Klump, Georg M

2016-07-01

The effect of interaural time difference (ITD) and interaural level difference (ILD) on wave 4 of the binaural and summed monaural auditory brainstem responses (ABRs) as well as on the DN1 component of the binaural interaction component (BIC) of the ABR in young and old Mongolian gerbils (Meriones unguiculatus) was investigated. Measurements were made at a fixed sound pressure level (SPL) and a fixed level above visually detected ABR threshold to compensate for individual hearing threshold differences. In both stimulation modes (fixed SPL and fixed level above visually detected ABR threshold) an effect of ITD on the latency and the amplitude of wave 4 as well as of the BIC was observed. With increasing absolute ITD values BIC latencies were increased and amplitudes were decreased. ILD had a much smaller effect on these measures. Old animals showed a reduced amplitude of the DN1 component. This difference was due to a smaller wave 4 in the summed monaural ABRs of old animals compared to young animals whereas wave 4 in the binaural-evoked ABR showed no age-related difference. In old animals the small amplitude of the DN1 component was correlated with small binaural-evoked wave 1 and wave 3 amplitudes. This suggests that the reduced peripheral input affects central binaural processing which is reflected in the BIC. Copyright © 2016 Elsevier B.V. All rights reserved.

Auditory agnosia as a clinical symptom of childhood adrenoleukodystrophy.

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Furushima, Wakana; Kaga, Makiko; Nakamura, Masako; Gunji, Atsuko; Inagaki, Masumi

2015-08-01

To investigate detailed auditory features in patients with auditory impairment as the first clinical symptoms of childhood adrenoleukodystrophy (CSALD). Three patients who had hearing difficulty as the first clinical signs and/or symptoms of ALD. Precise examination of the clinical characteristics of hearing and auditory function was performed, including assessments of pure tone audiometry, verbal sound discrimination, otoacoustic emission (OAE), and auditory brainstem response (ABR), as well as an environmental sound discrimination test, a sound lateralization test, and a dichotic listening test (DLT). The auditory pathway was evaluated by MRI in each patient. Poor response to calling was detected in all patients. Two patients were not aware of their hearing difficulty, and had been diagnosed with normal hearing by otolaryngologists at first. Pure-tone audiometry disclosed normal hearing in all patients. All patients showed a normal wave V ABR threshold. Three patients showed obvious difficulty in discriminating verbal sounds, environmental sounds, and sound lateralization and strong left-ear suppression in a dichotic listening test. However, once they discriminated verbal sounds, they correctly understood the meaning. Two patients showed elongation of the I-V and III-V interwave intervals in ABR, but one showed no abnormality. MRIs of these three patients revealed signal changes in auditory radiation including in other subcortical areas. The hearing features of these subjects were diagnosed as auditory agnosia and not aphasia. It should be emphasized that when patients are suspected to have hearing impairment but have no abnormalities in pure tone audiometry and/or ABR, this should not be diagnosed immediately as psychogenic response or pathomimesis, but auditory agnosia must also be considered. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Prevalence of auditory changes in newborns in a teaching hospital

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Guimarães, Valeriana de Castro

2012-01-01

Full Text Available Introduction: The precocious diagnosis and the intervention in the deafness are of basic importance in the infantile development. The loss auditory and more prevalent than other joined riots to the birth. Objective: Esteem the prevalence of auditory alterations in just-born in a hospital school. Method: Prospective transversal study that evaluated 226 just-been born, been born in a public hospital, between May of 2008 the May of 2009. Results: Of the 226 screened, 46 (20.4% had presented absence of emissions, having been directed for the second emission. Of the 26 (56.5% children who had appeared in the retest, 8 (30.8% had remained with absence and had been directed to the Otolaryngologist. Five (55.5% had appeared and had been examined by the doctor. Of these, 3 (75.0% had presented normal otoscopy, being directed for evaluation of the Evoked Potential Auditory of Brainstem (PEATE. Of the total of studied children, 198 (87.6% had had presence of emissions in one of the tests and, 2 (0.9% with deafness diagnosis. Conclusion: The prevalence of auditory alterations in the studied population was of 0,9%. The study it offers given excellent epidemiologists and it presents the first report on the subject, supplying resulted preliminary future implantation and development of a program of neonatal auditory selection.

Auditory attention: time of day and type of school

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Picolini, Mirela Machado

2010-06-01

Full Text Available Introduction: The sustained auditory attention is crucial for the development of some communication skills and learning. Objective: To evaluate the effect of time of day and type of school attended by children in their ability to sustained auditory attention. Method: We performed a prospective study of 50 volunteer children of both sexes, aged 7 years, with normal hearing, no learning or behavioral problems and no complaints of attention. These participants underwent Ability Test of Sustained Auditory Attention (SAAAT. The performance was evaluated by total score and the decrease of vigilance. Statistical analysis was used to analysis of variance (ANOVA with significance level of 5% (p<0.05. Results: The result set by the normative test for the age group evaluated showed a statistically significant difference for the errors of inattention (p=0.041, p=0.027 and total error score (p=0.033, p=0.024, in different periods assessment and school types, respectively. Conclusion: Children evaluated in the afternoon and the children studying in public schools had a poorer performance on auditory attention sustained.

Musical Sophistication and the Effect of Complexity on Auditory Discrimination in Finnish Speakers

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Dawson, Caitlin; Aalto, Daniel; Šimko, Juraj; Vainio, Martti; Tervaniemi, Mari

2017-01-01

Musical experiences and native language are both known to affect auditory processing. The present work aims to disentangle the influences of native language phonology and musicality on behavioral and subcortical sound feature processing in a population of musically diverse Finnish speakers as well as to investigate the specificity of enhancement from musical training. Finnish speakers are highly sensitive to duration cues since in Finnish, vowel and consonant duration determine word meaning. Using a correlational approach with a set of behavioral sound feature discrimination tasks, brainstem recordings, and a musical sophistication questionnaire, we find no evidence for an association between musical sophistication and more precise duration processing in Finnish speakers either in the auditory brainstem response or in behavioral tasks, but they do show an enhanced pitch discrimination compared to Finnish speakers with less musical experience and show greater duration modulation in a complex task. These results are consistent with a ceiling effect set for certain sound features which corresponds to the phonology of the native language, leaving an opportunity for music experience-based enhancement of sound features not explicitly encoded in the language (such as pitch, which is not explicitly encoded in Finnish). Finally, the pattern of duration modulation in more musically sophisticated Finnish speakers suggests integrated feature processing for greater efficiency in a real world musical situation. These results have implications for research into the specificity of plasticity in the auditory system as well as to the effects of interaction of specific language features with musical experiences. PMID:28450829

Musical Sophistication and the Effect of Complexity on Auditory Discrimination in Finnish Speakers.

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Dawson, Caitlin; Aalto, Daniel; Šimko, Juraj; Vainio, Martti; Tervaniemi, Mari

2017-01-01

Musical experiences and native language are both known to affect auditory processing. The present work aims to disentangle the influences of native language phonology and musicality on behavioral and subcortical sound feature processing in a population of musically diverse Finnish speakers as well as to investigate the specificity of enhancement from musical training. Finnish speakers are highly sensitive to duration cues since in Finnish, vowel and consonant duration determine word meaning. Using a correlational approach with a set of behavioral sound feature discrimination tasks, brainstem recordings, and a musical sophistication questionnaire, we find no evidence for an association between musical sophistication and more precise duration processing in Finnish speakers either in the auditory brainstem response or in behavioral tasks, but they do show an enhanced pitch discrimination compared to Finnish speakers with less musical experience and show greater duration modulation in a complex task. These results are consistent with a ceiling effect set for certain sound features which corresponds to the phonology of the native language, leaving an opportunity for music experience-based enhancement of sound features not explicitly encoded in the language (such as pitch, which is not explicitly encoded in Finnish). Finally, the pattern of duration modulation in more musically sophisticated Finnish speakers suggests integrated feature processing for greater efficiency in a real world musical situation. These results have implications for research into the specificity of plasticity in the auditory system as well as to the effects of interaction of specific language features with musical experiences.

Surgical management of spontaneous hypertensive brainstem hemorrhage

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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.

Evaluation of the Auditory Pathway in Traffic Policemen

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Vipul Indora

2017-04-01

Full Text Available Background: Traffic policemen working at heavy traffic junctions are continuously exposed to high level of noise and its health consequences. Objective: To assess the hearing pathway in traffic policemen by means of brainstem evoked response audiometry (BERA, mid-latency response (MLR, and slow vertex response (SVR. Methods: In this observational comparative study, BERA, MLR, and SVR were tested in 35 male traffic policemen with field posting of more than 3 years. 35 age-matched men working in our college served as controls. Results: Increase in the latencies of waves I and III of BERA, and IPL I-III were observed. Compared to controls, the MLR and SVR waves showed no significant changes in studied policemen. Conclusion: We found that chronic exposure of traffic policemen to noise resulted in delayed conduction in peripheral part of the auditory pathway, ie, auditory nerve up to the level of superior olivary nucleus; no impairment was observed at the level of sub-cortical, cortical, or the association areas.

Insult-induced adaptive plasticity of the auditory system

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Joshua R Gold

2014-05-01

Full Text Available The brain displays a remarkable capacity for both widespread and region-specific modifications in response to environmental challenges, with adaptive processes bringing about the reweighting of connections in neural networks putatively required for optimising performance and behaviour. As an avenue for investigation, studies centred around changes in the mammalian auditory system, extending from the brainstem to the cortex, have revealed a plethora of mechanisms that operate in the context of sensory disruption after insult, be it lesion-, noise trauma, drug-, or age-related. Of particular interest in recent work are those aspects of auditory processing which, after sensory disruption, change at multiple – if not all – levels of the auditory hierarchy. These include changes in excitatory, inhibitory and neuromodulatory networks, consistent with theories of homeostatic plasticity; functional alterations in gene expression and in protein levels; as well as broader network processing effects with cognitive and behavioural implications. Nevertheless, there abounds substantial debate regarding which of these processes may only be sequelae of the original insult, and which may, in fact, be maladaptively compelling further degradation of the organism’s competence to cope with its disrupted sensory context. In this review, we aim to examine how the mammalian auditory system responds in the wake of particular insults, and to disambiguate how the changes that develop might underlie a correlated class of phantom disorders, including tinnitus and hyperacusis, which putatively are brought about through maladaptive neuroplastic disruptions to auditory networks governing the spatial and temporal processing of acoustic sensory information.

A brainstem variant of reversible posterior leukoencephalopathy syndrome

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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.)

A brainstem variant of reversible posterior leukoencephalopathy syndrome

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Kitaguchi, H.; Tomimoto, H.; Terada, K.; Miki, Y.; Yamamoto, A.; Satoi, H.; Kanda, M.; Fukuyama, H.

2005-01-01

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.)

Deviance-Related Responses along the Auditory Hierarchy: Combined FFR, MLR and MMN Evidence

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Shiga, Tetsuya; Althen, Heike; Cornella, Miriam; Zarnowiec, Katarzyna; Yabe, Hirooki; Escera, Carles

2015-01-01

The mismatch negativity (MMN) provides a correlate of automatic auditory discrimination in human auditory cortex that is elicited in response to violation of any acoustic regularity. Recently, deviance-related responses were found at much earlier cortical processing stages as reflected by the middle latency response (MLR) of the auditory evoked potential, and even at the level of the auditory brainstem as reflected by the frequency following response (FFR). However, no study has reported deviance-related responses in the FFR, MLR and long latency response (LLR) concurrently in a single recording protocol. Amplitude-modulated (AM) sounds were presented to healthy human participants in a frequency oddball paradigm to investigate deviance-related responses along the auditory hierarchy in the ranges of FFR, MLR and LLR. AM frequency deviants modulated the FFR, the Na and Nb components of the MLR, and the LLR eliciting the MMN. These findings demonstrate that it is possible to elicit deviance-related responses at three different levels (FFR, MLR and LLR) in one single recording protocol, highlight the involvement of the whole auditory hierarchy in deviance detection and have implications for cognitive and clinical auditory neuroscience. Moreover, the present protocol provides a new research tool into clinical neuroscience so that the functional integrity of the auditory novelty system can now be tested as a whole in a range of clinical populations where the MMN was previously shown to be defective. PMID:26348628

Nonlinear development of the populations of neurons expressing c-Fos under sustained electrical intracochlear stimulation in the rat auditory brainstem.

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Rosskothen-Kuhl, Nicole; Illing, Robert-Benjamin

2010-08-06

The immediate-early-gene c-fos is among the first genes to be expressed following sensory-invoked neuronal activity. Its gene product c-Fos forms the limiting monomer of the heterodimeric activator protein-1 transcription factor that triggers various genes involved in neuroplastic remodeling. This study investigated the pattern of c-Fos expression in anteroventral (AVCN) and dorsal cochlear nucleus (DCN) and central inferior colliculus (CIC) after 45 min, 73 min, 2 h, 3:15 h and 5 h of unilateral electrical intracochlear stimulation (EIS) at 50 Hz in anaesthetized rats. Following EIS, tonotopic c-Fos expression was observed for each stimulation time in ipsilateral AVCN, DCN bilaterally, and contralateral CIC. By counting c-Fos positive nuclei, we discovered temporal non-linearities in the size of the respective population of c-Fos expressing neurons. In all regions investigated, the populations significantly increased from 73 min to 2 h but decreased towards 3:15 h. In AVCN, the number rose again by 5 h of EIS. Remarkably, the same was noted for neurons with large nuclei in deep DCN. In both regions, the population of responsive neurons shifted spatially: In central AVCN, the density of c-Fos positive cells increased significantly from 2 to 5h with medial and lateral regions remaining unchanged. In DCN, the density of large c-Fos positive nuclei fell in the upper and rose in the deep layers from 45 min to 5h of EIS. In conclusion, spatiotemporally varying recruitments of neuronal subpopulations into cellular networks responding to specific patterns of sensory activity take place in the auditory brainstem. Copyright 2010 Elsevier B.V. All rights reserved.

MRI findings of multiple sclerosis involving the brainstem

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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

Assessing Auditory Processing Abilities in Typically Developing School-Aged Children.

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McDermott, Erin E; Smart, Jennifer L; Boiano, Julie A; Bragg, Lisa E; Colon, Tiffany N; Hanson, Elizabeth M; Emanuel, Diana C; Kelly, Andrea S

2016-02-01

Large discrepancies exist in the literature regarding definition, diagnostic criteria, and appropriate assessment for auditory processing disorder (APD). Therefore, a battery of tests with normative data is needed. The purpose of this study is to collect normative data on a variety of tests for APD on children aged 7-12 yr, and to examine effects of outside factors on test performance. Children aged 7-12 yr with normal hearing, speech and language abilities, cognition, and attention were recruited for participation in this normative data collection. One hundred and forty-seven children were recruited using flyers and word of mouth. Of the participants recruited, 137 children qualified for the study. Participants attended schools located in areas that varied in terms of socioeconomic status, and resided in six different states. Audiological testing included a hearing screening (15 dB HL from 250 to 8000 Hz), word recognition testing, tympanometry, ipsilateral and contralateral reflexes, and transient-evoked otoacoustic emissions. The language, nonverbal IQ, phonological processing, and attention skills of each participant were screened using the Clinical Evaluation of Language Fundamentals-4 Screener, Test of Nonverbal Intelligence, Comprehensive Test of Phonological Processing, and Integrated Visual and Auditory-Continuous Performance Test, respectively. The behavioral APD battery included the following tests: Dichotic Digits Test, Frequency Pattern Test, Duration Pattern Test, Random Gap Detection Test, Compressed and Reverberated Words Test, Auditory Figure Ground (signal-to-noise ratio of +8 and +0), and Listening in Spatialized Noise-Sentences Test. Mean scores and standard deviations of each test were calculated, and analysis of variance tests were used to determine effects of factors such as gender, handedness, and birth history on each test. Normative data tables for the test battery were created for the following age groups: 7- and 8-yr-olds (n = 49), 9

Central auditory masking by an illusory tone.

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Christopher J Plack

Full Text Available Many natural sounds fluctuate over time. The detectability of sounds in a sequence can be reduced by prior stimulation in a process known as forward masking. Forward masking is thought to reflect neural adaptation or neural persistence in the auditory nervous system, but it has been unclear where in the auditory pathway this processing occurs. To address this issue, the present study used a "Huggins pitch" stimulus, the perceptual effects of which depend on central auditory processing. Huggins pitch is an illusory tonal sensation produced when the same noise is presented to the two ears except for a narrow frequency band that is different (decorrelated between the ears. The pitch sensation depends on the combination of the inputs to the two ears, a process that first occurs at the level of the superior olivary complex in the brainstem. Here it is shown that a Huggins pitch stimulus produces more forward masking in the frequency region of the decorrelation than a noise stimulus identical to the Huggins-pitch stimulus except with perfect correlation between the ears. This stimulus has a peripheral neural representation that is identical to that of the Huggins-pitch stimulus. The results show that processing in, or central to, the superior olivary complex can contribute to forward masking in human listeners.

A hardware model of the auditory periphery to transduce acoustic signals into neural activity

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Takashi eTateno

2013-11-01

Full Text Available To improve the performance of cochlear implants, we have integrated a microdevice into a model of the auditory periphery with the goal of creating a microprocessor. We constructed an artificial peripheral auditory system using a hybrid model in which polyvinylidene difluoride was used as a piezoelectric sensor to convert mechanical stimuli into electric signals. To produce frequency selectivity, the slit on a stainless steel base plate was designed such that the local resonance frequency of the membrane over the slit reflected the transfer function. In the acoustic sensor, electric signals were generated based on the piezoelectric effect from local stress in the membrane. The electrodes on the resonating plate produced relatively large electric output signals. The signals were fed into a computer model that mimicked some functions of inner hair cells, inner hair cell–auditory nerve synapses, and auditory nerve fibers. In general, the responses of the model to pure-tone burst and complex stimuli accurately represented the discharge rates of high-spontaneous-rate auditory nerve fibers across a range of frequencies greater than 1 kHz and middle to high sound pressure levels. Thus, the model provides a tool to understand information processing in the peripheral auditory system and a basic design for connecting artificial acoustic sensors to the peripheral auditory nervous system. Finally, we discuss the need for stimulus control with an appropriate model of the auditory periphery based on auditory brainstem responses that were electrically evoked by different temporal pulse patterns with the same pulse number.

Magnetic resonance imaging in the evaluation of the brainstem

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Han, J.S.; Bonstelle, C.T.; Kaufman, B.; Benson, J.E.; Alfidi, R.J.; Clampitt, M.; Van Dyke, C.; Huss, R.G.

1984-01-01

Magnetic resonance (MR) images of the brainstem region from 100 normal or asymptomatic individuals were reviewed in addition to those of 17 patients with intra-axial brainstem lesions and 15 patients with extra-axial masses around the brainstem. MR was able to demonstrate consistently the normal anatomy of the brainstem and adjacent cisterns, though the distinction between gray and white matter was seldom possible with the present technology. Masses in and around the brainstem were all accurately identified on MR and its sensitivity was superior to that of x-ray computed tomography (CT). These study results show that despite its technical limitations, MR is presently the examination of choice for the evaluation of brainstem abnormalities and eventually it will undoubtedly replace metrizamide CT cisternography

Preservation of auditory brainstem response thresholds after cochleostomy and titanium microactuator implantation in the lateral wall of cat scala tympani.

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Lesinski, S George; Prewitt, Jessica; Bray, Victor; Aravamudhan, Radhika; Bermeo Blanco, Oscar A; Farmer-Fedor, Brenda L; Ward, Jonette A

2014-04-01

The safety of implanting a titanium microactuator into the lateral wall of cat scala tympani was assessed by comparing preoperative and postoperative auditory brainstem response (ABR) thresholds for 1 to 3 months. The safety of directly stimulating cochlear perilymph with an implantable hearing system requires maintaining preoperative hearing levels. This cat study is an essential step in the development of the next generation of fully implantable hearing devices for humans. Following GLP surgical standards, a 1-mm cochleostomy was drilled into the lateral wall of the scala tympani, and a nonfunctioning titanium anchor/microactuator assembly was inserted in 8 cats. The scala media was damaged in the 1 cat. ABR thresholds with click and 4- and 8-kHz stimuli were measured preoperatively and compared with postoperative thresholds at 1, 2, and 3 months. Nonimplanted ear thresholds were also measured to establish statistical significance for threshold shifts (>28.4 dB). Two audiologists independently interpreted thresholds. Postoperatively, 7 cats implanted in the scala tympani demonstrated no significant ABR threshold shift for click stimulus; one shifted ABR thresholds to 4- and 8-kHz stimuli. The eighth cat, with surgical damage to the scala media, maintained stable click threshold but had a significant shift to 4- and 8-kHz stimuli. This cat study provides no evidence of worsening hearing thresholds after fenestration of the scala tympani and insertion of a titanium anchor/microactuator, provided there is no surgical trauma to the scala media and the implanted device is securely anchored in the cochleostomy. These 2 issues have been resolved in the development of a fully implantable hearing system for humans. The long-term hearing stability (combined with histologic studies) reaffirm that the microactuator is well tolerated by the cat cochlea.

Gamma Knife Treatment of Brainstem Metastases

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Peterson, Halloran E.; Larson, Erik W.; Fairbanks, Robert K.; MacKay, Alexander R.; Lamoreaux, Wayne T.; Call, Jason A.; Carlson, Jonathan D.; Ling, Benjamin C.; Demakas, John J.; Cooke, Barton S.; Peressini, Ben; Lee, Christopher M.

2014-01-01

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. PMID:24886816

Abnormalities in auditory efferent activities in children with selective mutism.

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Muchnik, Chava; Ari-Even Roth, Daphne; Hildesheimer, Minka; Arie, Miri; Bar-Haim, Yair; Henkin, Yael

2013-01-01

Two efferent feedback pathways to the auditory periphery may play a role in monitoring self-vocalization: the middle-ear acoustic reflex (MEAR) and the medial olivocochlear bundle (MOCB) reflex. Since most studies regarding the role of auditory efferent activity during self-vocalization were conducted in animals, human data are scarce. The working premise of the current study was that selective mutism (SM), a rare psychiatric disorder characterized by consistent failure to speak in specific social situations despite the ability to speak normally in other situations, may serve as a human model for studying the potential involvement of auditory efferent activity during self-vocalization. For this purpose, auditory efferent function was assessed in a group of 31 children with SM and compared to that of a group of 31 normally developing control children (mean age 8.9 and 8.8 years, respectively). All children exhibited normal hearing thresholds and type A tympanograms. MEAR and MOCB functions were evaluated by means of acoustic reflex thresholds and decay functions and the suppression of transient-evoked otoacoustic emissions, respectively. Auditory afferent function was tested by means of auditory brainstem responses (ABR). Results indicated a significantly higher proportion of children with abnormal MEAR and MOCB function in the SM group (58.6 and 38%, respectively) compared to controls (9.7 and 8%, respectively). The prevalence of abnormal MEAR and/or MOCB function was significantly higher in the SM group (71%) compared to controls (16%). Intact afferent function manifested in normal absolute and interpeak latencies of ABR components in all children. The finding of aberrant efferent auditory function in a large proportion of children with SM provides further support for the notion that MEAR and MOCB may play a significant role in the process of self-vocalization. © 2013 S. Karger AG, Basel.

Plasticity of peripheral auditory frequency sensitivity in Emei music frog.

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Zhang, Dian; Cui, Jianguo; Tang, Yezhong

2012-01-01

In anurans reproductive behavior is strongly seasonal. During the spring, frogs emerge from hibernation and males vocalize for mating or advertising territories. Female frogs have the ability to evaluate the quality of the males' resources on the basis of these vocalizations. Although studies revealed that central single torus semicircularis neurons in frogs exhibit season plasticity, the plasticity of peripheral auditory sensitivity in frog is unknown. In this study the seasonally plasticity of peripheral auditory sensitivity was test in the Emei music frog Babina daunchina, by comparing thresholds and latencies of auditory brainstem responses (ABRs) evoked by tone pips and clicks in the reproductive and non-reproductive seasons. The results show that both ABR thresholds and latency differ significantly between the reproductive and non-reproductive seasons. The thresholds of tone pip evoked ABRs in the non-reproductive season increased significantly about 10 dB than those in the reproductive season for frequencies from 1 KHz to 6 KHz. ABR latencies to waveform valley values for tone pips for the same frequencies using appropriate threshold stimulus levels are longer than those in the reproductive season for frequencies from 1.5 to 6 KHz range, although from 0.2 to 1.5 KHz range it is shorter in the non-reproductive season. These results demonstrated that peripheral auditory frequency sensitivity exhibits seasonal plasticity changes which may be adaptive to seasonal reproductive behavior in frogs.

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

The Role of Auditory Evoked Potentials in the Context of Cochlear Implant Provision.

Science.gov (United States)

Hoth, Sebastian; Dziemba, Oliver Christian

2017-12-01

: Auditory evoked potentials (AEP) are highly demanded during the whole process of equipping patients with cochlear implants (CI). They play an essential role in preoperative diagnostics, intraoperative testing, and postoperative monitoring of auditory performance and success. The versatility of AEP's is essentially enhanced by their property to be evokable by acoustic as well as electric stimuli. Thus, the electric responses of the auditory system following acoustic stimulation and recorded by the conventional surface technique as well as by transtympanic derivation from the promontory (Electrocochleography [ECochG]) are used for the quantitative determination of hearing loss and, additionally, electrically evoked compound actions potentials (ECAP) can be recorded with the intracochlear electrodes of the implant just adjacent to the stimulation electrode to check the functional integrity of the device and its coupling to the auditory system. The profile of ECAP thresholds is used as basis for speech processor fitting, the spread of excitation (SOE) allows the identification of electrode mislocations such as array foldover, and recovery functions may serve to optimize stimulus pulse rate. These techniques as well as those relying on scalp surface activity originating in the brainstem or the auditory cortex accompany the CI recipient during its whole life span and they offer valuable insights into functioning and possible adverse effects of the CI for clinical and scientific purposes.

Clinical Approach to Supranuclear Brainstem Saccadic Gaze Palsies

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Alexandra Lloyd-Smith Sequeira

2017-08-01

Full Text Available Failure of brainstem supranuclear centers for saccadic eye movements results in the clinical presence of a brainstem-mediated supranuclear saccadic gaze palsy (SGP, which is manifested as slowing of saccades with or without range of motion limitation of eye movements and as loss of quick phases of optokinetic nystagmus. Limitation in the range of motion of eye movements is typically worse with saccades than with smooth pursuit and is overcome with vestibular–ocular reflexive eye movements. The differential diagnosis of SGPs is broad, although acute-onset SGP is most often from brainstem infarction and chronic vertical SGP is most commonly caused by the neurodegenerative condition progressive supranuclear palsy. In this review, we discuss the brainstem anatomy and physiology of the brainstem saccade-generating network; we discuss the clinical features of SGPs, with an emphasis on insights from quantitative ocular motor recordings; and we consider the broad differential diagnosis of SGPs.

Age effects and normative data on a Dutch test battery for auditory processing disorders.

NARCIS (Netherlands)

Neijenhuis, C.A.M.; Snik, A.F.M.; Priester, G.; Kordenoordt, S. van; Broek, P. van den

2002-01-01

A test battery compiled to diagnose auditory processing disorders (APDs) in an adult population was used on a population of 9-16-year-old children. The battery consisted of eight tests (words -in noise, filtered speech, binaural fusion, dichotic digits, frequency and duration patterns, backward

Plasticity of peripheral auditory frequency sensitivity in Emei music frog.

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Dian Zhang

Full Text Available In anurans reproductive behavior is strongly seasonal. During the spring, frogs emerge from hibernation and males vocalize for mating or advertising territories. Female frogs have the ability to evaluate the quality of the males' resources on the basis of these vocalizations. Although studies revealed that central single torus semicircularis neurons in frogs exhibit season plasticity, the plasticity of peripheral auditory sensitivity in frog is unknown. In this study the seasonally plasticity of peripheral auditory sensitivity was test in the Emei music frog Babina daunchina, by comparing thresholds and latencies of auditory brainstem responses (ABRs evoked by tone pips and clicks in the reproductive and non-reproductive seasons. The results show that both ABR thresholds and latency differ significantly between the reproductive and non-reproductive seasons. The thresholds of tone pip evoked ABRs in the non-reproductive season increased significantly about 10 dB than those in the reproductive season for frequencies from 1 KHz to 6 KHz. ABR latencies to waveform valley values for tone pips for the same frequencies using appropriate threshold stimulus levels are longer than those in the reproductive season for frequencies from 1.5 to 6 KHz range, although from 0.2 to 1.5 KHz range it is shorter in the non-reproductive season. These results demonstrated that peripheral auditory frequency sensitivity exhibits seasonal plasticity changes which may be adaptive to seasonal reproductive behavior in frogs.

Five Elements of Normative Ethics - A General Theory of Normative Individualism

OpenAIRE

Pfordten, Dietmar

2012-01-01

The article tries to inquire a third way in normative ethics between consequentialism or utilitarianism and deontology or Kantianism. To find such a third way in normative ethics, one has to analyze the elements of these classical theories and to look if they are justified. In this article it is argued that an adequate normative ethics has to contain the following five elements: (1) normative individualism, i. e., the view that in the last instance moral norms and values can only be justified...

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

Baseline vestibular and auditory findings in a trial of post-concussive syndrome

Science.gov (United States)

Meehan, Anna; Searing, Elizabeth; Weaver, Lindell; Lewandowski, Andrew

2016-01-01

Previous studies have reported high rates of auditory and vestibular-balance deficits immediately following head injury. This study uses a comprehensive battery of assessments to characterize auditory and vestibular function in 71 U.S. military service members with chronic symptoms following mild traumatic brain injury that did not resolve with traditional interventions. The majority of the study population reported hearing loss (70%) and recent vestibular symptoms (83%). Central auditory deficits were most prevalent, with 58% of participants failing the SCAN3:A screening test and 45% showing abnormal responses on auditory steady-state response testing presented at a suprathreshold intensity. Only 17% of the participants had abnormal hearing (⟩25 dB hearing loss) based on the pure-tone average. Objective vestibular testing supported significant deficits in this population, regardless of whether the participant self-reported active symptoms. Composite score on the Sensory Organization Test was lower than expected from normative data (mean 69.6 ±vestibular tests, vestibulo-ocular reflex, central auditory dysfunction, mild traumatic brain injury, post-concussive symptoms, hearing15.6). High abnormality rates were found in funduscopy torsion (58%), oculomotor assessments (49%), ocular and cervical vestibular evoked myogenic potentials (46% and 33%, respectively), and monothermal calorics (40%). It is recommended that a full peripheral and central auditory, oculomotor, and vestibular-balance evaluation be completed on military service members who have sustained head trauma.

Stability of auditory discrimination and novelty processing in physiological aging.

Science.gov (United States)

Raggi, Alberto; Tasca, Domenica; Rundo, Francesco; Ferri, Raffaele

2013-01-01

Complex higher-order cognitive functions and their possible changes with aging are mandatory objectives of cognitive neuroscience. Event-related potentials (ERPs) allow investigators to probe the earliest stages of information processing. N100, Mismatch negativity (MMN) and P3a are auditory ERP components that reflect automatic sensory discrimination. The aim of the present study was to determine if N100, MMN and P3a parameters are stable in healthy aged subjects, compared to those of normal young adults. Normal young adults and older participants were assessed using standardized cognitive functional instruments and their ERPs were obtained with an auditory stimulation at two different interstimulus intervals, during a passive paradigm. All individuals were within the normal range on cognitive tests. No significant differences were found for any ERP parameters obtained from the two age groups. This study shows that aging is characterized by a stability of the auditory discrimination and novelty processing. This is important for the arrangement of normative for the detection of subtle preclinical changes due to abnormal brain aging.

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

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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

Craniofacial Pain: Brainstem Mechanisms

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Barry J Sessle

1996-01-01

Full Text Available This article reviews recent research advances in animals that have identified critical neural elements in the brainstem receiving and transmitting craniofacial nociceptive inputs, as well as some of the mechanisms involved in the modulation and plasticity of nociceptive transmission. Nociceptive neurones in the trigeminal (V brainstem sensory nuclear complex can be classified as nociceptive-specific (NS or wide dynamic range (WDR. Some of these neurones respond exclusively to sensory inputs evoked by stimulation of facial skin or oral mucosa and have features suggesting that they are critical neural elements involved in the ability to localize an acute superficial pain and sense its intensity and duration. Many of the V brainstem nociceptive neurones, however, receive convergent inputs from afferents supplying deep craniofacial tissues (eg, dural vessel, muscle and skin or mucosa. These neurones are likely involved in deep pain, including headache, because few nociceptive neurones receive inputs exclusively from afferents supplying these tissues. These extensive convergent input patterns also appear to be important factors in pain spread and referral, and in central mechanisms underlying neuroplastic changes in V neuronal properties that may occur with injury and inflammation. For example, application of the small fibre excitant and inflammatory irritant mustard oil into the temporomandibular joint, masseter or tongue musculature induces a prolonged but reversible enhancement of responses to cutaneous and deep afferent inputs of most WDR and NS neurones. These effects may be accompanied by increased electromyographic activity reflexly induced in the masticatory muscles by mustard oil, and involve endogenous N-methyl-D-aspartate and opioid neurochemical mechanisms. Such peripherally induced modulation of brainstem nociceptive neuronal properties reflects the functional plasticity of the central V system, and may be involved in the development of

Benefits and detriments of unilateral cochlear implant use on bilateral auditory development in children who are deaf

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Karen A. Gordon

2013-10-01

Full Text Available We have explored both the benefits and detriments of providing electrical input through a cochlear implant in one ear to the auditory system of young children. A cochlear implant delivers electrical pulses to stimulate the auditory nerve, providing children who are deaf with access to sound. The goals of implantation are to restrict reorganization of the deprived immature auditory brain and promote development of hearing and spoken language. It is clear that limiting the duration of deprivation is a key factor. Additional considerations are the onset, etiology, and use of residual hearing as each of these can have unique effects on auditory development in the pre-implant period. New findings show that many children receiving unilateral cochlear implants are developing mature-like brainstem and thalamo-cortical responses to sound with long term use despite these sources of variability; however, there remain considerable abnormalities in cortical function. The most apparent, determined by implanting the other ear and measuring responses to acute stimulation, is a loss of normal cortical response from the deprived ear. Recent data reveal that this can be avoided in children by early implantation of both ears simultaneously or with limited delay. We conclude that auditory development requires input early in development and from both ears.

Arterial territories of human brain: brainstem and cerebellum

International Nuclear Information System (INIS)

Tatu, L.; Moulin, T.; Bogousslavsky, J.; Duvernoy, H.

1997-01-01

The development of neuroimaging has allowed clinicians to improve clinico-anatomic correlations in patients with strokes. Brainstem and cerebellum structures are well delineated on MRI, but there is a lack of standardization in their arterial supply. We present a system of 12 brainstem and cerebellum axial sections, depicting the dominant arterial territories and the most important anatomic structures. These sections may be used as a practical tool to determine arterial territories on MRI, and may help establish consistent clinico-anatomic correlations in patients with brainstem and cerebellar ischemic strokes. (authors)

Brainstem tumors: Current management and future directions

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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.

Reverberation impairs brainstem temporal representations of voiced vowel sounds: challenging periodicity-tagged segregation of competing speech in rooms

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Mark eSayles

2015-01-01

Full Text Available The auditory system typically processes information from concurrently active sound sources (e.g., two voices speaking at once, in the presence of multiple delayed, attenuated and distorted sound-wave reflections (reverberation. Brainstem circuits help segregate these complex acoustic mixtures into auditory objects. Psychophysical studies demonstrate a strong interaction between reverberation and fundamental-frequency (F0 modulation, leading to impaired segregation of competing vowels when segregation is on the basis of F0 differences. Neurophysiological studies of complex-sound segregation have concentrated on sounds with steady F0s, in anechoic environments. However, F0 modulation and reverberation are quasi-ubiquitous.We examine the ability of 129 single units in the ventral cochlear nucleus of the anesthetized guinea pig to segregate the concurrent synthetic vowel sounds /a/ and /i/, based on temporal discharge patterns under closed-field conditions. We address the effects of added real-room reverberation, F0 modulation, and the interaction of these two factors, on brainstem neural segregation of voiced speech sounds. A firing-rate representation of single-vowels’ spectral envelopes is robust to the combination of F0 modulation and reverberation: local firing-rate maxima and minima across the tonotopic array code vowel-formant structure. However, single-vowel F0-related periodicity information in shuffled inter-spike interval distributions is significantly degraded in the combined presence of reverberation and F0 modulation. Hence, segregation of double-vowels’ spectral energy into two streams (corresponding to the two vowels, on the basis of temporal discharge patterns, is impaired by reverberation; specifically when F0 is modulated. All unit types (primary-like, chopper, onset are similarly affected. These results offer neurophysiological insights to perceptual organization of complex acoustic scenes under realistically challenging

Pediatric brainstem oligodendroglioma

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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.

Acute Noise Exposure Is Associated With Intrinsic Apoptosis in Murine Central Auditory Pathway

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Moritz Gröschel

2018-05-01

Full Text Available Noise that is capable of inducing the hearing loss (NIHL has a strong impact on the inner ear structures and causes early and most obvious pathophysiological changes in the auditory periphery. Several studies indicated that intrinsic apoptotic cell death mechanisms are the key factors inducing cellular degeneration immediately after noise exposure and are maintained for days or even weeks. In addition, studies demonstrated several changes in the central auditory system following noise exposure, consistent with early apoptosis-related pathologies. To clarify the underlying mechanisms, the present study focused on the noise-induced gene and protein expression of the pro-apoptotic protease activating factor-1 (APAF1 and the anti-apoptotic B-cell lymphoma 2 related protein a1a (BCL2A1A in the cochlear nucleus (CN, inferior colliculus (IC and auditory cortex (AC of the murine central auditory pathway. The expression of Bcl2a1a mRNA was upregulated immediately after trauma in all tissues investigated, whereas the protein levels were significantly reduced at least in the auditory brainstem. Conversely, acute noise has decreased the expression of Apaf1 gene along the auditory pathway. The changes in APAF1 protein level were not statistically significant. It is tempting to speculate that the acoustic overstimulation leads to mitochondrial dysfunction and induction of apoptosis by regulation of proapoptotic and antiapoptotic proteins. The inverse expression pattern on the mRNA level of both genes might reflect a protective response to decrease cellular damage. Our results indicate the immediate presence of intrinsic apoptosis following noise trauma. This, in turn, may significantly contribute to the development of central structural deficits. Auditory pathway-specific inhibition of intrinsic apoptosis could be a therapeutic approach for the treatment of acute (noise-induced hearing loss to prevent irreversible neuronal injury in auditory brain structures

Glycinergic transmission modulates GABAergic inhibition in the avian auditory pathway

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Matthew J Fischl

2014-03-01

Full Text Available For all neurons, a proper balance of synaptic excitation and inhibition is crucial to effect computational precision. Achievement of this balance is remarkable when one considers factors that modulate synaptic strength operate on multiple overlapping time scales and affect both pre- and postsynaptic elements. Recent studies have shown that inhibitory transmitters, glycine and GABA, are co-released in auditory nuclei involved in the computation of interaural time disparities (ITDs, a cue used to process sound source location. The co-release expressed at these synapses is heavily activity dependent, and generally occurs when input rates are high. This circuitry, in both birds and mammals, relies on inhibitory input to maintain the temporal precision necessary for ITD encoding. Studies of co-release in other brain regions suggest that GABA and glycine receptors (GlyRs interact via cross-suppressive modulation of receptor conductance. We performed in vitro whole-cell recordings in several nuclei of the chicken brainstem auditory circuit to assess whether this cross-suppressive phenomenon was evident in the avian brainstem. We evaluated the effect of pressure-puff applied glycine on synaptically evoked inhibitory currents in nucleus magnocellularis (NM and the superior olivary nucleus (SON. Glycine pre-application reduced the amplitude of inhibitory postsynaptic currents evoked during a 100Hz train stimulus in both nuclei. This apparent glycinergic modulation was blocked in the presence of strychnine. Further experiments showed that this modulation did not depend on postsynaptic biochemical interactions such as phosphatase activity, or direct interactions between GABA and glycine receptor proteins. Rather, voltage clamp experiments in which we manipulated Cl- flux during agonist application suggest that activation of one receptor will modulate the conductance of the other via local changes in Cl- ion concentration within microdomains of the

Challenge-driven attention: interacting frontal and brainstem systems

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Rajeev D S Raizada

2008-03-01

Full Text Available The world is an unpredictable place, presenting challenges that fl uctuate from moment to moment. However, the neural systems for responding to such challenges are far from fully understood. Using fMRI, we studied an audiovisual task in which the trials' diffi culty and onset times varied unpredictably. Two regions were found to increase their activation for challenging trials, with their activities strongly correlated: right frontal cortex and the brainstem. The frontal area matched regions found in previous human studies of cognitive control, and activated in a graded manner with increasing task diffi culty. The brainstem responded only to the most diffi cult trials, showing a phasic activity pattern paralleling locus coeruleus recordings in monkeys. These results reveal a bridge between animal and human studies, and suggest interacting roles for the brainstem and right frontal cortex: the brainstem may signal that an attentional challenge is occurring, while right frontal cortex allocates cognitive resources in response.

Normative interpretations of diversity

DEFF Research Database (Denmark)

Lægaard, Sune

2009-01-01

Normative interpretations of particular cases consist of normative principles or values coupled with social theoretical accounts of the empirical facts of the case. The article reviews the most prominent normative interpretations of the Muhammad cartoons controversy over the publication of drawings...... of the Prophet Muhammad in the Danish newspaper Jyllands-Posten. The controversy was seen as a case of freedom of expression, toleration, racism, (in)civility and (dis)respect, and the article notes different understandings of these principles and how the application of them to the controversy implied different...... social theoretical accounts of the case. In disagreements between different normative interpretations, appeals are often made to the ‘context', so it is also considered what roles ‘context' might play in debates over normative interpretations...

The ethics of normative power

OpenAIRE

Beiniks, Stacia

2015-01-01

peer-reviewed The question addressed by this research is; how can the concept of normative power be morally evaluated? In general terms, normative power is thought to be an ability or disposition, where A has normative power when it is able to diffuse through communicative acts a norm n to B. However, prevailing theories also assume that all uses of normative power are justified, and that this is dependent on the norm promoted being defined as valid. This alters the definition of normative...

Magnetic resonance imaging in brain-stem tumors

International Nuclear Information System (INIS)

Nomura, Mikio; Saito, Hisazumi; Akino, Minoru; Abe, Hiroshi.

1988-01-01

Four patients with brain-stem tumors underwent magnetic resonance imaging (MRI) before and after radiotherapy. The brain-stem tumors were seen as a low signal intensity on T1-weighted images and as a high signal intensity on T2-weighted images. A tumor and its anatomic involvement were more clearly visualized on MRI than on cuncurrently performed CT. Changes in tumor before and after radiotherapy could be determined by measuring the diameter of tumor on sagittal and coronal images. This allowed quantitative evaluation of the reduction of tumor in association with improvement of symptoms. The mean T1 value in the central part of tumors was shortened in all patients after radiotherapy. The results indicate that MRI may assist in determining the effect of radiotherapy for brain-stem tumors. (Namekawa, K)

Blast-Induced Tinnitus and Elevated Central Auditory and Limbic Activity in Rats: A Manganese-Enhanced MRI and Behavioral Study.

Science.gov (United States)

Ouyang, Jessica; Pace, Edward; Lepczyk, Laura; Kaufman, Michael; Zhang, Jessica; Perrine, Shane A; Zhang, Jinsheng

2017-07-07

Blast-induced tinitus is the number one service-connected disability that currently affects military personnel and veterans. To elucidate its underlying mechanisms, we subjected 13 Sprague Dawley adult rats to unilateral 14 psi blast exposure to induce tinnitus and measured auditory and limbic brain activity using manganese-enhanced MRI (MEMRI). Tinnitus was evaluated with a gap detection acoustic startle reflex paradigm, while hearing status was assessed with prepulse inhibition (PPI) and auditory brainstem responses (ABRs). Both anxiety and cognitive functioning were assessed using elevated plus maze and Morris water maze, respectively. Five weeks after blast exposure, 8 of the 13 blasted rats exhibited chronic tinnitus. While acoustic PPI remained intact and ABR thresholds recovered, the ABR wave P1-N1 amplitude reduction persisted in all blast-exposed rats. No differences in spatial cognition were observed, but blasted rats as a whole exhibited increased anxiety. MEMRI data revealed a bilateral increase in activity along the auditory pathway and in certain limbic regions of rats with tinnitus compared to age-matched controls. Taken together, our data suggest that while blast-induced tinnitus may play a role in auditory and limbic hyperactivity, the non-auditory effects of blast and potential traumatic brain injury may also exert an effect.

Brainstem disconnection

International Nuclear Information System (INIS)

Duffield, Curtis; Wootton-Gorges, Sandra L.; Jocson, Jennifer

2009-01-01

Brainstem disconnection is a very rare neonatal abnormality, with only seven cases reported. We report a unique case of a neonate who presented at delivery with hypertonia, dysmorphic facial features, and respiratory distress, as well as numerous musculoskeletal and genitourinary abnormalities. MRI of the brain showed disconnection between the pons and medulla with cerebellar hypoplasia and absent cerebellar peduncles. It aided in the description of the neurological and vascular anomalies associated with this diagnosis. (orig.)

Brainstem disconnection

Energy Technology Data Exchange (ETDEWEB)

Duffield, Curtis; Wootton-Gorges, Sandra L. [University of California Davis, Medical Center and UC Davis Children' s Hospital, Department of Radiology, Sacramento, CA (United States); Jocson, Jennifer [University of California Davis, Medical Center and UC Davis Children' s Hospital, Department of Pediatrics, Sacramento, CA (United States)

2009-12-15

Brainstem disconnection is a very rare neonatal abnormality, with only seven cases reported. We report a unique case of a neonate who presented at delivery with hypertonia, dysmorphic facial features, and respiratory distress, as well as numerous musculoskeletal and genitourinary abnormalities. MRI of the brain showed disconnection between the pons and medulla with cerebellar hypoplasia and absent cerebellar peduncles. It aided in the description of the neurological and vascular anomalies associated with this diagnosis. (orig.)

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.)

Lyme disease of the brainstem

International Nuclear Information System (INIS)

Kalina, Peter; Decker, Andrew; Kornel, Ezriel; Halperin, John J.

2005-01-01

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.)

Systematic Morphometry of Catecholamine Nuclei in the Brainstem.

Science.gov (United States)

Bucci, Domenico; Busceti, Carla L; Calierno, Maria T; Di Pietro, Paola; Madonna, Michele; Biagioni, Francesca; Ryskalin, Larisa; Limanaqi, Fiona; Nicoletti, Ferdinando; Fornai, Francesco

2017-01-01

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.

Systematic Morphometry of Catecholamine Nuclei in the Brainstem

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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.

Early postnatal virus inoculation into the scala media achieved extensive expression of exogenous green fluorescent protein in the inner ear and preserved auditory brainstem response thresholds.

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Wang, Yunfeng; Sun, Yu; Chang, Qing; Ahmad, Shoeb; Zhou, Binfei; Kim, Yeunjung; Li, Huawei; Lin, Xi

2013-01-01

Gene transfer into the inner ear is a promising approach for treating sensorineural hearing loss. The special electrochemical environment of the scala media raises a formidable challenge for effective gene delivery at the same time as keeping normal cochlear function intact. The present study aimed to define a suitable strategy for preserving hearing after viral inoculation directly into the scala media performed at various postnatal developmental stages. We assessed transgene expression of green fluorescent protein (GFP) mediated by various types of adeno-associated virus (AAV) and lentivirus (LV) in the mouse cochlea. Auditory brainstem responses were measured 30 days after inoculation to assess effects on hearing. Patterns of GFP expression confirmed extensive exogenous gene expression in various types of cells lining the endolymphatic space. The use of different viral vectors and promoters resulted in specific cellular GFP expression patterns. AAV2/1 with cytomegalovirus promoter apparently gave the best results for GFP expression in the supporting cells. Histological examination showed normal cochlear morphology and no hair cell loss after either AAV or LV injections. We found that hearing thresholds were not significantly changed when the injections were performed in mice younger than postnatal day 5, regardless of the type of virus tested. Viral inoculation and expression in the inner ear for the restoration of hearing must not damage cochlear function. Using normal hearing mice as a model, we have achieved this necessary step, which is required for the treatment of many types of congenital deafness that require early intervention. Copyright © 2013 John Wiley & Sons, Ltd.

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

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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.

Normative social influence is underdetected.

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Nolan, Jessica M; Schultz, P Wesley; Cialdini, Robert B; Goldstein, Noah J; Griskevicius, Vladas

2008-07-01

The present research investigated the persuasive impact and detectability of normative social influence. The first study surveyed 810 Californians about energy conservation and found that descriptive normative beliefs were more predictive of behavior than were other relevant beliefs, even though respondents rated such norms as least important in their conservation decisions. Study 2, a field experiment, showed that normative social influence produced the greatest change in behavior compared to information highlighting other reasons to conserve, even though respondents rated the normative information as least motivating. Results show that normative messages can be a powerful lever of persuasion but that their influence is underdetected.

Co-operatives and Normative Control

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Bregn, Kirsten; Jagd, Søren

1992-01-01

This paper explores the conditions for applying normative control in co-operatives. For normative control to be effective two conditions are found particularly important: Individuals must be morally involved and the organization must have a system of making it possible to link common norms...... and individual action. If these conditions are not fulfilled, as may be the case in many co-operatives, normative control cannot be expected to work. The problems of normative control in co-operatives may then not be caused by the use of normative control as such, but may instead be a problem of securing...

Auditory and Visual Electrophysiology of Deaf Children with Cochlear Implants: Implications for Cross-modal Plasticity.

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Corina, David P; Blau, Shane; LaMarr, Todd; Lawyer, Laurel A; Coffey-Corina, Sharon

2017-01-01

Deaf children who receive a cochlear implant early in life and engage in intensive oral/aural therapy often make great strides in spoken language acquisition. However, despite clinicians' best efforts, there is a great deal of variability in language outcomes. One concern is that cortical regions which normally support auditory processing may become reorganized for visual function, leaving fewer available resources for auditory language acquisition. The conditions under which these changes occur are not well understood, but we may begin investigating this phenomenon by looking for interactions between auditory and visual evoked cortical potentials in deaf children. If children with abnormal auditory responses show increased sensitivity to visual stimuli, this may indicate the presence of maladaptive cortical plasticity. We recorded evoked potentials, using both auditory and visual paradigms, from 25 typical hearing children and 26 deaf children (ages 2-8 years) with cochlear implants. An auditory oddball paradigm was used (85% /ba/ syllables vs. 15% frequency modulated tone sweeps) to elicit an auditory P1 component. Visual evoked potentials (VEPs) were recorded during presentation of an intermittent peripheral radial checkerboard while children watched a silent cartoon, eliciting a P1-N1 response. We observed reduced auditory P1 amplitudes and a lack of latency shift associated with normative aging in our deaf sample. We also observed shorter latencies in N1 VEPs to visual stimulus offset in deaf participants. While these data demonstrate cortical changes associated with auditory deprivation, we did not find evidence for a relationship between cortical auditory evoked potentials and the VEPs. This is consistent with descriptions of intra-modal plasticity within visual systems of deaf children, but do not provide evidence for cross-modal plasticity. In addition, we note that sign language experience had no effect on deaf children's early auditory and visual ERP

Distribution of glutamatergic, GABAergic, and glycinergic neurons in the auditory pathways of macaque monkeys.

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Ito, T; Inoue, K; Takada, M

2015-12-03

Macaque monkeys use complex communication calls and are regarded as a model for studying the coding and decoding of complex sound in the auditory system. However, little is known about the distribution of excitatory and inhibitory neurons in the auditory system of macaque monkeys. In this study, we examined the overall distribution of cell bodies that expressed mRNAs for VGLUT1, and VGLUT2 (markers for glutamatergic neurons), GAD67 (a marker for GABAergic neurons), and GLYT2 (a marker for glycinergic neurons) in the auditory system of the Japanese macaque. In addition, we performed immunohistochemistry for VGLUT1, VGLUT2, and GAD67 in order to compare the distribution of proteins and mRNAs. We found that most of the excitatory neurons in the auditory brainstem expressed VGLUT2. In contrast, the expression of VGLUT1 mRNA was restricted to the auditory cortex (AC), periolivary nuclei, and cochlear nuclei (CN). The co-expression of GAD67 and GLYT2 mRNAs was common in the ventral nucleus of the lateral lemniscus (VNLL), CN, and superior olivary complex except for the medial nucleus of the trapezoid body, which expressed GLYT2 alone. In contrast, the dorsal nucleus of the lateral lemniscus, inferior colliculus, thalamus, and AC expressed GAD67 alone. The absence of co-expression of VGLUT1 and VGLUT2 in the medial geniculate, medial superior olive, and VNLL suggests that synaptic responses in the target neurons of these nuclei may be different between rodents and macaque monkeys. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Against essential normativity of the mental

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Steglich-Petersen, Asbjørn

2008-01-01

A number of authors have recently developed and defended various versions of ‘normative essentialism’ about the mental, i.e. the claim that propositional attitudes are constitutively or essentially governed by normative principles. I present two arguments to the effect that this claim cannot be r...... essentially normative, propositional attitude ascriptions could not support normative rationality judgments, which would remove the central appeal of normative essentialism....

Inner ear anatomy in Waardenburg syndrome: radiological assessment and comparison with normative data.

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Kontorinis, Georgios; Goetz, Friedrich; Lanfermann, Heinrich; Luytenski, Stefan; Giesemann, Anja M

2014-08-01

As patients with Waardenburg syndrome (WS) represent potential candidates for cochlear implantation, their inner ear anatomy is of high significance. There is an ongoing debate whether WS is related to any inner ear dysplasias. Our objective was to evaluate radiologically the inner ear anatomy in patients with WS and identify any temporal bone malformations. A retrospective case review was carried out in a tertiary, referral center. The high resolution computed tomography (HRCT) scans of the temporal bone from 20 patients (40 ears) with WS who were managed for deafness in a tertiary referral center from 1995 to 2012 were retrospectively examined. Measurements of 15 different inner ear dimensions, involving the cochlea, the vestibule, the semicircular canals and the internal auditory meatus, as well as measurements of the vestibular aqueduct, were performed independently by two neuroradiologists. Finally, we compared the results from the WS group with a control group consisting of 50 normal hearing subjects (100 ears) and with previously reported normative values. Inner ear malformations were not found in any of the patients with WS. All measured inner ear dimensions were within the normative values compiled by our study group as well as by others. Inner ear malformations are not characteristic for all types of WS; however, certain rare subtypes might be related to inner ear deformities. Normative cochleovestibular dimensions that can help in assessing the temporal bone anatomy are provided. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Auditory-motor learning influences auditory memory for music.

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Brown, Rachel M; Palmer, Caroline

2012-05-01

In two experiments, we investigated how auditory-motor learning influences performers' memory for music. Skilled pianists learned novel melodies in four conditions: auditory only (listening), motor only (performing without sound), strongly coupled auditory-motor (normal performance), and weakly coupled auditory-motor (performing along with auditory recordings). Pianists' recognition of the learned melodies was better following auditory-only or auditory-motor (weakly coupled and strongly coupled) learning than following motor-only learning, and better following strongly coupled auditory-motor learning than following auditory-only learning. Auditory and motor imagery abilities modulated the learning effects: Pianists with high auditory imagery scores had better recognition following motor-only learning, suggesting that auditory imagery compensated for missing auditory feedback at the learning stage. Experiment 2 replicated the findings of Experiment 1 with melodies that contained greater variation in acoustic features. Melodies that were slower and less variable in tempo and intensity were remembered better following weakly coupled auditory-motor learning. These findings suggest that motor learning can aid performers' auditory recognition of music beyond auditory learning alone, and that motor learning is influenced by individual abilities in mental imagery and by variation in acoustic features.

A clinical study of brainstem infarction identified on magnetic resonance imaging

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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).

Effects of prematurity on language acquisition and auditory maturation: a systematic review.

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Rechia, Inaê Costa; Oliveira, Luciéle Dias; Crestani, Anelise Henrich; Biaggio, Eliara Pinto Vieira; Souza, Ana Paula Ramos de

2016-01-01

To verify which damages prematurity causes to hearing and language. We used the decriptors language/linguagem, hearing/audição, prematurity/prematuridade in databases LILACS, MEDLINE, Cochrane Library and Scielo. randomized controlled trials, non-randomized intervention studies and descriptive studies (cross-sectional, cohort, case-control projects). The articles were assessed independently by two authors according to the selection criteria. Twenty-six studies were selected, of which seven were published in Brazil and 19 in international literature. Nineteen studies comparing full-term and preterm infants. Two of the studies made comparisons between premature infants small for gestational age and appropriate for gestational age. In four studies, the sample consisted of children with extreme prematurity, while other studies have been conducted in children with severe and moderate prematurity. To assess hearing, these studies used otoacoustic emissions, brainstem evoked potentials, tympanometry, auditory steady-state response and visual reinforcement audiometry. For language assessment, most of the articles used the Bayley Scale of Infant and Toddler Development. Most studies reviewed observed that prematurity is directly or indirectly related to the acquisition of auditory and language abilities early in life. Thus, it could be seen that prematurity, as well as aspects related to it (gestational age, low weight at birth and complications at birth), affect maturation of the central auditory pathway and may cause negative effects on language acquisition.

Auditory and verbal memory predictors of spoken language skills in children with cochlear implants.

Science.gov (United States)

de Hoog, Brigitte E; Langereis, Margreet C; van Weerdenburg, Marjolijn; Keuning, Jos; Knoors, Harry; Verhoeven, Ludo

2016-10-01

Large variability in individual spoken language outcomes remains a persistent finding in the group of children with cochlear implants (CIs), particularly in their grammatical development. In the present study, we examined the extent of delay in lexical and morphosyntactic spoken language levels of children with CIs as compared to those of a normative sample of age-matched children with normal hearing. Furthermore, the predictive value of auditory and verbal memory factors in the spoken language performance of implanted children was analyzed. Thirty-nine profoundly deaf children with CIs were assessed using a test battery including measures of lexical, grammatical, auditory and verbal memory tests. Furthermore, child-related demographic characteristics were taken into account. The majority of the children with CIs did not reach age-equivalent lexical and morphosyntactic language skills. Multiple linear regression analyses revealed that lexical spoken language performance in children with CIs was best predicted by age at testing, phoneme perception, and auditory word closure. The morphosyntactic language outcomes of the CI group were best predicted by lexicon, auditory word closure, and auditory memory for words. Qualitatively good speech perception skills appear to be crucial for lexical and grammatical development in children with CIs. Furthermore, strongly developed vocabulary skills and verbal memory abilities predict morphosyntactic language skills. Copyright © 2016 Elsevier Ltd. All rights reserved.

Is enhanced MRI helpful in brainstem infarction?

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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.

A novel auditory ossicles membrane and the development of conductive hearing loss in Dmp1-null mice.

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Lv, Kun; Huang, Haiyang; Yi, Xing; Chertoff, Mark E; Li, Chaoyuan; Yuan, Baozhi; Hinton, Robert J; Feng, Jian Q

2017-10-01

Genetic mouse models are widely used for understanding human diseases but we know much less about the anatomical structure of the auditory ossicles in the mouse than we do about human ossicles. Furthermore, current studies have mainly focused on disease conditions such as osteomalacia and rickets in patients with hypophosphatemia rickets, although the reason that these patients develop late-onset hearing loss is unknown. In this study, we first analyzed Dmp1 lac Z knock-in auditory ossicles (in which the blue reporter is used to trace DMP1 expression in osteocytes) using X-gal staining and discovered a novel bony membrane surrounding the mouse malleus. This finding was further confirmed by 3-D micro-CT, X-ray, and alizarin red stained images. We speculate that this unique structure amplifies and facilitates sound wave transmissions in two ways: increasing the contact surface between the eardrum and malleus and accelerating the sound transmission due to its mineral content. Next, we documented a progressive deterioration in the Dmp1-null auditory ossicle structures using multiple imaging techniques. The auditory brainstem response test demonstrated a conductive hearing loss in the adult Dmp1-null mice. This finding may help to explain in part why patients with DMP1 mutations develop late-onset hearing loss, and supports the critical role of DMP1 in maintaining the integrity of the auditory ossicles and its bony membrane. Copyright © 2017 Elsevier Inc. All rights reserved.

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

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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.

Speech and non-speech processing in children with phonological disorders: an electrophysiological study

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Isabela Crivellaro Gonçalves

2011-01-01

Full Text Available OBJECTIVE: To determine whether neurophysiological auditory brainstem responses to clicks and repeated speech stimuli differ between typically developing children and children with phonological disorders. INTRODUCTION: Phonological disorders are language impairments resulting from inadequate use of adult phonological language rules and are among the most common speech and language disorders in children (prevalence: 8 - 9%. Our hypothesis is that children with phonological disorders have basic differences in the way that their brains encode acoustic signals at brainstem level when compared to normal counterparts. METHODS: We recorded click and speech evoked auditory brainstem responses in 18 typically developing children (control group and in 18 children who were clinically diagnosed with phonological disorders (research group. The age range of the children was from 7-11 years. RESULTS: The research group exhibited significantly longer latency responses to click stimuli (waves I, III and V and speech stimuli (waves V and A when compared to the control group. DISCUSSION: These results suggest that the abnormal encoding of speech sounds may be a biological marker of phonological disorders. However, these results cannot define the biological origins of phonological problems. We also observed that speech-evoked auditory brainstem responses had a higher specificity/sensitivity for identifying phonological disorders than click-evoked auditory brainstem responses. CONCLUSIONS: Early stages of the auditory pathway processing of an acoustic stimulus are not similar in typically developing children and those with phonological disorders. These findings suggest that there are brainstem auditory pathway abnormalities in children with phonological disorders.

The auditory processing battery: survey of common practices.

Science.gov (United States)

Emanuel, Diana C

2002-02-01

A survey of auditory processing (AP) diagnostic practices was mailed to all licensed audiologists in the State of Maryland and sent as an electronic mail attachment to the American Speech-Language-Hearing Association and Educational Audiology Association Internet forums. Common AP protocols (25 from the Internet, 28 from audiologists in Maryland) included requiring basic audiologic testing, using questionnaires, and administering dichotic listening, monaural low-redundancy speech, temporal processing, and electrophysiologic tests. Some audiologists also administer binaural interaction, attention, memory, and speech-language/psychological/educational tests and incorporate a classroom observation. The various AP batteries presently administered appear to be based on the availability of AP tests with well-documented normative data. Resources for obtaining AP tests are listed.

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.)

Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

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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.)

Analysis of diffuse brain injury with primary brainstem lesion on MRI

International Nuclear Information System (INIS)

Shibata, Masayoshi; Matsumae, Mitsunori; Shimoda, Masami; Ishizaka, Hideo; Shiramizu, Hideki; Morita, Seiji; Tsugane, Ryuichi

2003-01-01

It has been reported that diffuse brain injury patients with primary brainstem lesions have a poor prognosis. Predicting the existence of brainstem injury at hospital arrival is problematic in actual clinical practice. We conducted magnetic resonance imaging (MRI), to visualize brainstem lesions clearly, and retrospectively analyzed predictive factors of brainstem lesions by stepwise multiple logistic regression analysis of patient characteristics, neurological findings, laboratory data, and CT findings at arrival in each case. We compared 24 patients with brainstem lesion and 60 without using MRI obtained less than 3 weeks after admission. Items investigated were blood pressure immediately after hospital arrival, arterial blood gas analysis, existence of abnormal respiration, blow direction, Glasgow coma scale (GCS), light reflex, oculocephalic reflex, corneal reflex, intracranial pressure, jugular venous oxygen saturation, and CT findings such as existence of subarachnoid hemorrhage at the suprasellar cistern, perimesencephalic cistern and convexity, lesions on the thalamus and basal ganglia, gliding contusion, intraventricular hemorrhage and Traumatic Coma Data Bank classification. Independent predictive factors of primary brainstem lesion included impaired light reflex (odds ratio: 2.269), subarachnoid hemorrhage at convexity (odds ratio: 3.592) and suprasellar cistern (odds ratio: 2.458), and Traumatic Coma Data Bank group III (odds ratio: 11.062). (author)

Handheld tympanometer measurements in conscious dogs for the evaluation of the middle ear and auditory tube.

Science.gov (United States)

Strain, George M; Fernandes, Asia J

2015-06-01

Otitis externa is frequently accompanied by otitis media, yet it can be difficult to evaluate the tympanum, middle ear and auditory tube without the use of advanced radiographic imaging. The objective was to develop techniques for tympanometry testing in conscious dogs and to present normative data for clinical use of this equipment to enable assessment of the tympanum, middle ear and auditory tube. Sixteen hounds (14 female) from a school teaching colony. Dogs were gently restrained in a standing position. After cleaning of the ear canal, a tympanometer probe tip extension was placed in the vertical canal and automated testing performed using a handheld device. Both ears were tested in all dogs. Acceptable recordings were obtained from both ears of 13 dogs, from one ear in each of two dogs and from neither ear of one dog, resulting in data from 28 of 32 (88%) ears. Otoscopic examination confirmed the absence of inflammation or any other obvious explanation for the noncompliant dogs. No significant differences were seen between ears for any measure. Normative data are reported for peak compliance, peak compliance pressure, gradient and ear canal volume. Tympanograms can be recorded in conscious dogs to assist in the evaluation of the middle ear structures. © 2015 ESVD and ACVD.

Giant tubercular brainstem abscess: A case report

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Pragati Chigurupati

2014-01-01

Full Text Available Tubercular brain abscesses are uncommon and tubercular brainstem abscesses are rarely reported. Most of these cases occur in immunocompromised patients. We report a case of giant brainstem abscess in a 5-year-old human immunodeficiency virus-seronegative female child who presented with complaints of headache, diplopia and unsteadiness of gait since 6 months. Diagnosis was made by a magnetic resonance imaging scan of brain. The patient demonstrated a remarkable clinical recovery after microsurgery combined with a course of antituberculous therapy. Microbiological and histological findings confirmed the diagnosis of a tuberculous abscess.

Clinical and radiological features of hypertensive brainstem encephalopathy

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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

Non-normative Critique

DEFF Research Database (Denmark)

Hansen, Magnus Paulsen

2016-01-01

The close ties between modes of governing, subjectivities and critique in contemporary societies challenge the role of critical social research. The classical normative ethos of the unmasking researcher unravelling various oppressive structures of dominant vs. dominated groups in society is inade......The close ties between modes of governing, subjectivities and critique in contemporary societies challenge the role of critical social research. The classical normative ethos of the unmasking researcher unravelling various oppressive structures of dominant vs. dominated groups in society...... outlines a non-normative but critical programme based on an ethos of re-politicizing contemporary pervasive modes of governing. The analytical advantages and limitations of such a programme are demonstrated by readings of both Foucauldian studies and the works of and debates regarding the French pragmatic...

A probabilistic atlas of human brainstem pathways based on connectome imaging data.

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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

Auditory-steady-state response reliability in the audiological diagnosis after neonatal hearing screening.

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Núñez-Batalla, Faustino; Noriega-Iglesias, Sabel; Guntín-García, Maite; Carro-Fernández, Pilar; Llorente-Pendás, José Luis

2016-01-01

Conventional audiometry is the gold standard for quantifying and describing hearing loss. Alternative methods become necessary to assess subjects who are too young to respond reliably. Auditory evoked potentials constitute the most widely used method for determining hearing thresholds objectively; however, this stimulus is not frequency specific. The advent of the auditory steady-state response (ASSR) leads to more specific threshold determination. The current study describes and compares ASSR, auditory brainstem response (ABR) and conventional behavioural tone audiometry thresholds in a group of infants with various degrees of hearing loss. A comparison was made between ASSR, ABR and behavioural hearing thresholds in 35 infants detected in the neonatal hearing screening program. Mean difference scores (±SD) between ABR and high frequency ABR thresholds were 11.2 dB (±13) and 10.2 dB (±11). Pearson correlations between the ASSR and audiometry thresholds were 0.80 and 0.91 (500Hz); 0.84 and 0.82 (1000Hz); 0.85 and 0.84 (2000Hz); and 0.83 and 0.82 (4000Hz). The ASSR technique is a valuable extension of the clinical test battery for hearing-impaired children. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Familiar auditory sensory training in chronic traumatic brain injury: a case study.

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Sullivan, Emily Galassi; Guernon, Ann; Blabas, Brett; Herrold, Amy A; Pape, Theresa L-B

2018-04-01

The evaluation and treatment for patients with prolonged periods of seriously impaired consciousness following traumatic brain injury (TBI), such as a vegetative or minimally conscious state, poses considerable challenges, particularly in the chronic phases of recovery. This blinded crossover study explored the effects of familiar auditory sensory training (FAST) compared with a sham stimulation in a patient seven years post severe TBI. Baseline data were collected over 4 weeks to account for variability in status with neurobehavioral measures, including the Disorders of Consciousness scale (DOCS), Coma Near Coma scale (CNC), and Consciousness Screening Algorithm. Pre-stimulation neurophysiological assessments were completed as well, namely Brainstem Auditory Evoked Potentials (BAEP) and Somatosensory Evoked Potentials (SSEP). Results revealed that a significant improvement in the DOCS neurobehavioral findings after FAST, which was not maintained during the sham. BAEP findings also improved with maintenance of these improvements following sham stimulation as evidenced by repeat testing. The results emphasize the importance for continued evaluation and treatment of individuals in chronic states of seriously impaired consciousness with a variety of tools. Further study of auditory stimulation as a passive treatment paradigm for this population is warranted. Implications for Rehabilitation Clinicians should be equipped with treatment options to enhance neurobehavioral improvements when traditional treatment methods fail to deliver or maintain functional behavioral changes. Routine assessment is crucial to detect subtle changes in neurobehavioral function even in chronic states of disordered consciousness and determine potential preserved cognitive abilities that may not be evident due to unreliable motor responses given motoric impairments. Familiar Auditory Stimulation Training (FAST) is an ideal passive stimulation that can be supplied by families, allied health

Positron Emission Tomography Imaging Reveals Auditory and Frontal Cortical Regions Involved with Speech Perception and Loudness Adaptation.

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Georg Berding

Full Text Available Considerable progress has been made in the treatment of hearing loss with auditory implants. However, there are still many implanted patients that experience hearing deficiencies, such as limited speech understanding or vanishing perception with continuous stimulation (i.e., abnormal loudness adaptation. The present study aims to identify specific patterns of cerebral cortex activity involved with such deficiencies. We performed O-15-water positron emission tomography (PET in patients implanted with electrodes within the cochlea, brainstem, or midbrain to investigate the pattern of cortical activation in response to speech or continuous multi-tone stimuli directly inputted into the implant processor that then delivered electrical patterns through those electrodes. Statistical parametric mapping was performed on a single subject basis. Better speech understanding was correlated with a larger extent of bilateral auditory cortex activation. In contrast to speech, the continuous multi-tone stimulus elicited mainly unilateral auditory cortical activity in which greater loudness adaptation corresponded to weaker activation and even deactivation. Interestingly, greater loudness adaptation was correlated with stronger activity within the ventral prefrontal cortex, which could be up-regulated to suppress the irrelevant or aberrant signals into the auditory cortex. The ability to detect these specific cortical patterns and differences across patients and stimuli demonstrates the potential for using PET to diagnose auditory function or dysfunction in implant patients, which in turn could guide the development of appropriate stimulation strategies for improving hearing rehabilitation. Beyond hearing restoration, our study also reveals a potential role of the frontal cortex in suppressing irrelevant or aberrant activity within the auditory cortex, and thus may be relevant for understanding and treating tinnitus.

Positron Emission Tomography Imaging Reveals Auditory and Frontal Cortical Regions Involved with Speech Perception and Loudness Adaptation.

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Berding, Georg; Wilke, Florian; Rode, Thilo; Haense, Cathleen; Joseph, Gert; Meyer, Geerd J; Mamach, Martin; Lenarz, Minoo; Geworski, Lilli; Bengel, Frank M; Lenarz, Thomas; Lim, Hubert H

2015-01-01

Considerable progress has been made in the treatment of hearing loss with auditory implants. However, there are still many implanted patients that experience hearing deficiencies, such as limited speech understanding or vanishing perception with continuous stimulation (i.e., abnormal loudness adaptation). The present study aims to identify specific patterns of cerebral cortex activity involved with such deficiencies. We performed O-15-water positron emission tomography (PET) in patients implanted with electrodes within the cochlea, brainstem, or midbrain to investigate the pattern of cortical activation in response to speech or continuous multi-tone stimuli directly inputted into the implant processor that then delivered electrical patterns through those electrodes. Statistical parametric mapping was performed on a single subject basis. Better speech understanding was correlated with a larger extent of bilateral auditory cortex activation. In contrast to speech, the continuous multi-tone stimulus elicited mainly unilateral auditory cortical activity in which greater loudness adaptation corresponded to weaker activation and even deactivation. Interestingly, greater loudness adaptation was correlated with stronger activity within the ventral prefrontal cortex, which could be up-regulated to suppress the irrelevant or aberrant signals into the auditory cortex. The ability to detect these specific cortical patterns and differences across patients and stimuli demonstrates the potential for using PET to diagnose auditory function or dysfunction in implant patients, which in turn could guide the development of appropriate stimulation strategies for improving hearing rehabilitation. Beyond hearing restoration, our study also reveals a potential role of the frontal cortex in suppressing irrelevant or aberrant activity within the auditory cortex, and thus may be relevant for understanding and treating tinnitus.

Expression and function of scleraxis in the developing auditory system.

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Zoe F Mann

Full Text Available A study of genes expressed in the developing inner ear identified the bHLH transcription factor Scleraxis (Scx in the developing cochlea. Previous work has demonstrated an essential role for Scx in the differentiation and development of tendons, ligaments and cells of chondrogenic lineage. Expression in the cochlea has been shown previously, however the functional role for Scx in the cochlea is unknown. Using a Scx-GFP reporter mouse line we examined the spatial and temporal patterns of Scx expression in the developing cochlea between embryonic day 13.5 and postnatal day 25. Embryonically, Scx is expressed broadly throughout the cochlear duct and surrounding mesenchyme and at postnatal ages becomes restricted to the inner hair cells and the interdental cells of the spiral limbus. Deletion of Scx results in hearing impairment indicated by elevated auditory brainstem response (ABR thresholds and diminished distortion product otoacoustic emission (DPOAE amplitudes, across a range of frequencies. No changes in either gross cochlear morphology or expression of the Scx target genes Col2A, Bmp4 or Sox9 were observed in Scx(-/- mutants, suggesting that the auditory defects observed in these animals may be a result of unidentified Scx-dependent processes within the cochlea.

Attention effects at auditory periphery derived from human scalp potentials: displacement measure of potentials.

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Ikeda, Kazunari; Hayashi, Akiko; Sekiguchi, Takahiro; Era, Shukichi

2006-10-01

It is known in humans that electrophysiological measures such as the auditory brainstem response (ABR) are difficult to identify the attention effect at the auditory periphery, whereas the centrifugal effect has been detected by measuring otoacoustic emissions. This research developed a measure responsive to the shift of human scalp potentials within a brief post-stimulus period (13 ms), that is, displacement percentage, and applied it to an experiment to retrieve the peripheral attention effect. In the present experimental paradigm, tone pips were exposed to the left ear whereas the other ear was masked by white noise. Twelve participants each conducted two conditions of either ignoring or attending to the tone pips. Relative to averaged scalp potentials in the ignoring condition, the shift of the potentials was found within early component range during the attentive condition, and displacement percentage then revealed a significant magnitude difference between the two conditions. These results suggest that, using a measure representing the potential shift itself, the peripheral effect of attention can be detected from human scalp potentials.

Evidence for altered basal ganglia-brainstem connections in cervical dystonia.

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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.

Non-Monotonic Relation Between Noise Exposure Severity and Neuronal Hyperactivity in the Auditory Midbrain

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Lara Li Hesse

2016-08-01

Full Text Available The occurrence of tinnitus can be linked to hearing loss in the majority of cases, but there is nevertheless a large degree of unexplained heterogeneity in the relation between hearing loss and tinnitus. Part of the problem might be that hearing loss is usually quantified in terms of increased hearing thresholds, which only provides limited information about the underlying cochlear damage. Moreover, noise exposure that does not cause hearing threshold loss can still lead to hidden hearing loss (HHL, i.e. functional deafferentation of auditory nerve fibres (ANFs through loss of synaptic ribbons in inner hair cells. Whilst it is known that increased hearing thresholds can trigger increases in spontaneous neural activity in the central auditory system, i.e. a putative neural correlate of tinnitus, the central effects of HHL have not yet been investigated. Here, we exposed mice to octave-band noise at 100 and 105 dB SPL, to generate HHL and permanent increases of hearing thresholds, respectively. Deafferentation of ANFs was confirmed through measurement of auditory brainstem responses and cochlear immunohistochemistry. Acute extracellular recordings from the auditory midbrain (inferior colliculus demonstrated increases in spontaneous neuronal activity (a putative neural correlate of tinnitus in both groups. Surprisingly the increase in spontaneous activity was most pronounced in the mice with HHL, suggesting that the relation between hearing loss and neuronal hyperactivity might be more complex than currently understood. Our computational model indicated that these differences in neuronal hyperactivity could arise from different degrees of deafferentation of low-threshold ANFs in the two exposure groups.Our results demonstrate that HHL is sufficient to induce changes in central auditory processing, and they also indicate a non-monotonic relationship between cochlear damage and neuronal hyperactivity, suggesting an explanation for why tinnitus might

Normative and counter-normative stress messages and symptom reporting: implications for health promotion and a methodological artefact for stress research.

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Ferguson, Eamonn; Lawrence, Claire

2013-05-01

There is increasing use of counter-normative health messages (i.e., evidence-based health information about cause-effect relationships that run counter to shared normative beliefs, e.g., stress can lead to personal growth). The current studies examine the effect of normative and counter-normative messages about stress on levels of symptom reporting. Predictions are derived from reactance, social comparison, and self-enhancement theories. Two studies focus on the development of the messages, and two experimental studies examine the effect of manipulating normative and counter-normative messages on symptom reports. The final study controls for mere-measurement effects and explores the role of stress process variables (appraisals and coping). Exposure to a normative message (stress causes ill health) results in reduced symptom reporting compared to a counter-normative message (stress provides challenge, growth, and development) and control groups. The results suggest that people may use symptom reporting strategically to indicate coping. Based on the argument that beliefs about stress and health are stored as mental models, the theoretical associations derived from stress theory are only observed when a normative message is presented. Counter-normative stress messages may carry no tangible benefits compared to normative messages. Some stress research may suffer from inherent methodological bias when normative information is provided in information and consent sheets. Statement of contribution What is already known on this subject? At present, nothing is known about counter-normative health messages, despite the fact that they are becoming widely used as a public intervention. What does this study add? A clear operational definition of counter-normative messages. A test of three competing theories for counter-normative messages that focus of the stress-symptom link. Demonstrating for the first time, that in the domain of stress and health, counter-normative messages

Auditory-neurophysiological responses to speech during early childhood: Effects of background noise.

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White-Schwoch, Travis; Davies, Evan C; Thompson, Elaine C; Woodruff Carr, Kali; Nicol, Trent; Bradlow, Ann R; Kraus, Nina

2015-10-01

properties in this age group. These normative metrics may be useful clinically to evaluate auditory processing difficulties during early childhood. Copyright © 2015 Elsevier B.V. All rights reserved.

Intraparenchymal papillary meningioma of brainstem: case report and literature review

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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.

Mouse Panx1 Is Dispensable for Hearing Acquisition and Auditory Function.

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Zorzi, Veronica; Paciello, Fabiola; Ziraldo, Gaia; Peres, Chiara; Mazzarda, Flavia; Nardin, Chiara; Pasquini, Miriam; Chiani, Francesco; Raspa, Marcello; Scavizzi, Ferdinando; Carrer, Andrea; Crispino, Giulia; Ciubotaru, Catalin D; Monyer, Hannah; Fetoni, Anna R; M Salvatore, Anna; Mammano, Fabio

2017-01-01

Panx1 forms plasma membrane channels in brain and several other organs, including the inner ear. Biophysical properties, activation mechanisms and modulators of Panx1 channels have been characterized in detail, however the impact of Panx1 on auditory function is unclear due to conflicts in published results. To address this issue, hearing performance and cochlear function of the Panx1 -/- mouse strain, the first with a reported global ablation of Panx1 , were scrutinized. Male and female homozygous ( Panx1 -/-), hemizygous ( Panx1 +/-) and their wild type (WT) siblings ( Panx1 +/+) were used for this study. Successful ablation of Panx1 was confirmed by RT-PCR and Western immunoblotting in the cochlea and brain of Panx1 -/- mice. Furthermore, a previously validated Panx1-selective antibody revealed strong immunoreactivity in WT but not in Panx1 -/- cochleae. Hearing sensitivity, outer hair cell-based "cochlear amplifier" and cochlear nerve function, analyzed by auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) recordings, were normal in Panx1 +/- and Panx1 -/- mice. In addition, we determined that global deletion of Panx1 impacts neither on connexin expression, nor on gap-junction coupling in the developing organ of Corti. Finally, spontaneous intercellular Ca 2+ signal (ICS) activity in organotypic cochlear cultures, which is key to postnatal development of the organ of Corti and essential for hearing acquisition, was not affected by Panx1 ablation. Therefore, our results provide strong evidence that, in mice, Panx1 is dispensable for hearing acquisition and auditory function.

The Structural, Functional and Molecular Organization of the Brainstem

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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.

Glycinergic Pathways of the Central Auditory System and Adjacent Reticular Formation of the Rat.

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Hunter, Chyren

The development of techniques to visualize and identify specific transmitters of neuronal circuits has stimulated work on the characterization of pathways in the rat central nervous system that utilize the inhibitory amino acid glycine as its neurotransmitter. Glycine is a major inhibitory transmitter in the spinal cord and brainstem of vertebrates where it satisfies the major criteria for neurotransmitter action. Some of these characteristics are: uneven distribution in brain, high affinity reuptake mechanisms, inhibitory neurophysiological actions on certain neuronal populations, uneven receptor distribution and the specific antagonism of its actions by the convulsant alkaloid strychnine. Behaviorally, antagonism of glycinergic neurotransmission in the medullary reticular formation is linked to the development of myoclonus and seizures which may be initiated by auditory as well as other stimuli. In the present study, decreases in the concentration of glycine as well as the density of glycine receptors in the medulla with aging were found and may be responsible for the lowered threshold for strychnine seizures observed in older rats. Neuroanatomical pathways in the central auditory system and medullary and pontine reticular formation (RF) were investigated using retrograde transport of tritiated glycine to identify glycinergic pathways; immunohistochemical techniques were used to corroborate the location of glycine neurons. Within the central auditory system, retrograde transport studies using tritiated glycine demonstrated an ipsilateral glycinergic pathway linking nuclei of the ascending auditory system. This pathway has its cell bodies in the medial nucleus of the trapezoid body (MNTB) and projects to the ventrocaudal division of the ventral nucleus of the lateral lemniscus (VLL). Collaterals of this glycinergic projection terminate in the ipsilateral lateral superior olive (LSO). Other glycinergic pathways found were afferent to the VLL and have their origin

Integrated empirical ethics: loss of normativity?

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van der Scheer, Lieke; Widdershoven, Guy

2004-01-01

An important discussion in contemporary ethics concerns the relevance of empirical research for ethics. Specifically, two crucial questions pertain, respectively, to the possibility of inferring normative statements from descriptive statements, and to the danger of a loss of normativity if normative statements should be based on empirical research. Here we take part in the debate and defend integrated empirical ethical research: research in which normative guidelines are established on the basis of empirical research and in which the guidelines are empirically evaluated by focusing on observable consequences. We argue that in our concrete example normative statements are not derived from descriptive statements, but are developed within a process of reflection and dialogue that goes on within a specific praxis. Moreover, we show that the distinction in experience between the desirable and the undesirable precludes relativism. The normative guidelines so developed are both critical and normative: they help in choosing the right action and in evaluating that action. Finally, following Aristotle, we plead for a return to the view that morality and ethics are inherently related to one another, and for an acknowledgment of the fact that moral judgments have their origin in experience which is always related to historical and cultural circumstances.

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

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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.

Effects of chronic exposure to electromagnetic waves on the auditory system.

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Özgür, Abdulkadir; Tümkaya, Levent; Terzi, Suat; Kalkan, Yıldıray; Erdivanlı, Özlem Çelebi; Dursun, Engin

2015-08-01

The results support that chronic electromagnetic field exposure may cause damage by leading to neuronal degeneration of the auditory system. Numerous researches have been done about the risks of exposure to the electromagnetic fields that occur during the use of these devices, especially the effects on hearing. The aim of this study is to evaluate the effects of the electromagnetic waves emitted by the mobile phones through the electrophysiological and histological methods. Twelve adult Wistar albino rats were included in the study. The rats were divided into two groups of six rats. The study group was exposed to the electromagnetic waves over a period of 30 days. The control group was not given any exposure to the electromagnetic fields. After the completion of the electromagnetic wave application, the auditory brainstem responses of both groups were recorded under anesthesia. The degeneration of cochlear nuclei was graded by two different histologists, both of whom were blinded to group information. The histopathologic and immunohistochemical analysis showed neuronal degeneration signs, such as increased vacuolization in the cochlear nucleus, pyknotic cell appearance, and edema in the group exposed to the electromagnetic fields compared to the control group. The average latency of wave in the ABR was similar in both groups (p > 0.05).

Lack of protection against gentamicin ototoxicity by auditory conditioning with noise

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Alex Strose

2014-10-01

Full Text Available INTRODUCTION: Auditory conditioning consists of the pre-exposure to low levels of a potential harmful agent to protect against a subsequent harmful presentation. OBJECTIVE: To confirm if conditioning with an agent different from the used to cause the trauma can also be effective. METHOD: Experimental study with 17 guinea pigs divided as follows: group Som: exposed to 85 dB broadband noise centered at 4 kHz, 30 minutes a day for 10 consecutive days; group Cont: intramuscular administration of gentamicin 160 mg/kg a day for 10 consecutive days; group Expt: conditioned with noise similarly to group Som and, after each noise presentation, received gentamicin similarly to group Cont. The animals were evaluated by distortion product otoacoustic emissions (DPOAEs, brainstem auditory evoked potentials (BAEPs and scanning electron microscopy. RESULTS: The animals that were conditioned with noise did not show any protective effect compared to the ones that received only the ototoxic gentamicin administration. This lack of protection was observed functionally and morphologically. CONCLUSION: Conditioning with 85 dB broadband noise, 30 min a day for 10 consecutive days does not protect against an ototoxic gentamicin administration of 160 mg/kg a day for 10 consecutive days in the guinea pig.

Intraoperative Electrocochleographic Characteristics of Auditory Neuropathy Spectrum Disorder in Cochlear Implant Subjects

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William J. Riggs

2017-07-01

Full Text Available Auditory neuropathy spectrum disorder (ANSD is characterized by an apparent discrepancy between measures of cochlear and neural function based on auditory brainstem response (ABR testing. Clinical indicators of ANSD are a present cochlear microphonic (CM with small or absent wave V. Many identified ANSD patients have speech impairment severe enough that cochlear implantation (CI is indicated. To better understand the cochleae identified with ANSD that lead to a CI, we performed intraoperative round window electrocochleography (ECochG to tone bursts in children (n = 167 and adults (n = 163. Magnitudes of the responses to tones of different frequencies were summed to measure the “total response” (ECochG-TR, a metric often dominated by hair cell activity, and auditory nerve activity was estimated visually from the compound action potential (CAP and auditory nerve neurophonic (ANN as a ranked “Nerve Score”. Subjects identified as ANSD (45 ears in children, 3 in adults had higher values of ECochG-TR than adult and pediatric subjects also receiving CIs not identified as ANSD. However, nerve scores of the ANSD group were similar to the other cohorts, although dominated by the ANN to low frequencies more than in the non-ANSD groups. To high frequencies, the common morphology of ANSD cases was a large CM and summating potential, and small or absent CAP. Common morphologies in other groups were either only a CM, or a combination of CM and CAP. These results indicate that responses to high frequencies, derived primarily from hair cells, are the main source of the CM used to evaluate ANSD in the clinical setting. However, the clinical tests do not capture the wide range of neural activity seen to low frequency sounds.

Tonotopic alterations in inhibitory input to the medial nucleus of the trapezoid body in a mouse model of Fragile X syndrome.

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McCullagh, Elizabeth A; Salcedo, Ernesto; Huntsman, Molly M; Klug, Achim

2017-11-01

Hyperexcitability and the imbalance of excitation/inhibition are one of the leading causes of abnormal sensory processing in Fragile X syndrome (FXS). The precise timing and distribution of excitation and inhibition is crucial for auditory processing at the level of the auditory brainstem, which is responsible for sound localization ability. Sound localization is one of the sensory abilities disrupted by loss of the Fragile X Mental Retardation 1 (Fmr1) gene. Using triple immunofluorescence staining we tested whether there were alterations in the number and size of presynaptic structures for the three primary neurotransmitters (glutamate, glycine, and GABA) in the auditory brainstem of Fmr1 knockout mice. We found decreases in either glycinergic or GABAergic inhibition to the medial nucleus of the trapezoid body (MNTB) specific to the tonotopic location within the nucleus. MNTB is one of the primary inhibitory nuclei in the auditory brainstem and participates in the sound localization process with fast and well-timed inhibition. Thus, a decrease in inhibitory afferents to MNTB neurons should lead to greater inhibitory output to the projections from this nucleus. In contrast, we did not see any other significant alterations in balance of excitation/inhibition in any of the other auditory brainstem nuclei measured, suggesting that the alterations observed in the MNTB are both nucleus and frequency specific. We furthermore show that glycinergic inhibition may be an important contributor to imbalances in excitation and inhibition in FXS and that the auditory brainstem is a useful circuit for testing these imbalances. © 2017 Wiley Periodicals, Inc.

Dietary structured triacylglycerols containing docosahexaenoic acid given from birth affect visual and auditory performance and tissue fatty acid profiles of rats

DEFF Research Database (Denmark)

Christensen, M. M.; Lund, S. P.; Simonsen, L.

1998-01-01

To examine whether it is possible to enhance the level of 22:6(n-3) in the central nervous system, newborn rats were fed dietary supplements containing oils with either specific or random triacylglycerol structure, but similar concentrations of polyunsaturated fatty acids. In the specific structu...... in differences in learning ability, but caused changes in visual function, evidenced by higher latency of the b-wave and lower oscillatory potential, and in auditory brainstem response, evidenced by generally greater amplitude of wave la in the group fed specific structured oil....

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

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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.

Normative Power Europe

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Manners, Ian

2009-01-01

The chapter develops a normative power approach to European studies that can be applied across and beyond its constitutive disciplines in order to interrogate and transgress the ideas and spaces on/of Europe. In four parts the chapter explores the terms ‘normative', ‘power', and ‘Europe', before......' - in order to make sense of ideas of the common good. Part two looks at three different types of power - ‘relational', ‘structural', and ‘normative' - as a means of understanding the power of ideas of the common good. Part three considers three different means of understanding Europe - ‘civilizational......', ‘categorical', and ‘cultural' - to show how the power of ideas of the common good shape our means of comprehending contemporary Europe. Part four attempts to apply the approach to the question of a European counter-terrorist response. This example was chosen because of the challenges it presents...

Auditory agnosia.

Science.gov (United States)

Slevc, L Robert; Shell, Alison R

2015-01-01

Auditory agnosia refers to impairments in sound perception and identification despite intact hearing, cognitive functioning, and language abilities (reading, writing, and speaking). Auditory agnosia can be general, affecting all types of sound perception, or can be (relatively) specific to a particular domain. Verbal auditory agnosia (also known as (pure) word deafness) refers to deficits specific to speech processing, environmental sound agnosia refers to difficulties confined to non-speech environmental sounds, and amusia refers to deficits confined to music. These deficits can be apperceptive, affecting basic perceptual processes, or associative, affecting the relation of a perceived auditory object to its meaning. This chapter discusses what is known about the behavioral symptoms and lesion correlates of these different types of auditory agnosia (focusing especially on verbal auditory agnosia), evidence for the role of a rapid temporal processing deficit in some aspects of auditory agnosia, and the few attempts to treat the perceptual deficits associated with auditory agnosia. A clear picture of auditory agnosia has been slow to emerge, hampered by the considerable heterogeneity in behavioral deficits, associated brain damage, and variable assessments across cases. Despite this lack of clarity, these striking deficits in complex sound processing continue to inform our understanding of auditory perception and cognition. © 2015 Elsevier B.V. All rights reserved.

Diffusion tensor imaging of the brainstem in children with achondroplasia.

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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

Identifying cochlear implant channels with poor electrode-neuron interface: electrically-evoked auditory brainstem responses measured with the partial tripolar configuration

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Bierer, Julie Arenberg; Faulkner, Kathleen F.; Tremblay, Kelly L.

2011-01-01

Objectives The goal of this study was to compare cochlear implant behavioral measures and electrically-evoked auditory brainstem responses (EABRs) obtained with a spatially focused electrode configuration. It has been shown previously that channels with high thresholds, when measured with the tripolar configuration, exhibit relatively broad psychophysical tuning curves (Bierer and Faulkner, 2010). The elevated threshold and degraded spatial/spectral selectivity of such channels are consistent with a poor electrode-neuron interface, such as suboptimal electrode placement or reduced nerve survival. However, the psychophysical methods required to obtain these data are time intensive and may not be practical during a clinical mapping procedure, especially for young children. Here we have extended the previous investigation to determine if a physiological approach could provide a similar assessment of channel functionality. We hypothesized that, in accordance with the perceptual measures, higher EABR thresholds would correlate with steeper EABR amplitude growth functions, reflecting a degraded electrode-neuron interface. Design Data were collected from six cochlear implant listeners implanted with the HiRes 90k cochlear implant (Advanced Bionics). Single-channel thresholds and most comfortable listening levels were obtained for stimuli that varied in presumed electrical field size by using the partial tripolar configuration, for which a fraction of current (σ) from a center active electrode returns through two neighboring electrodes and the remainder through a distant indifferent electrode. EABRs were obtained in each subject for the two channels having the highest and lowest tripolar (σ=1 or 0.9) behavioral threshold. Evoked potentials were measured with both the monopolar (σ=0) and a more focused partial tripolar (σ ≥ 0.50) configuration. Results Consistent with previous studies, EABR thresholds were highly and positively correlated with behavioral thresholds

Dangerous Dogs, Constructivism and Normativity

DEFF Research Database (Denmark)

Hansen, Allan Dreyer

2010-01-01

This article argues that although there is no necessary link between constructivism and particular sets of norms, constructivism opens up a space for normativity and can be articulated through particular normative or political programs. I show how Laclau’s deconstructive constructivism can...

A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

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Fu, Xiujuan; Lu, Zuneng; Wang, Yan; Huang, Lifang; Wang, Xi; Zhang, Hong; Xiao, Zheman

2017-01-01

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. PMID:29311895

A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

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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.

Vestibular myogenic and acoustical brainstem evoked potentials in neurological practice

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O. S. Korepina

2012-01-01

Full Text Available Along with the inspection of acoustical cortex and brainstem EP in neurologic, otoneurologic and audiologic practice recently start to use so-called vestibular evoked myogenic potentials (VEMP. It is shown, that at ear stimulation by a loud sound and record of sterno-cleidomastoid contraction is possible to estimate function of the inferior vestibular nerve and vestibulospinal pathways, a sacculo-cervical reflex. In article some methodical and clinical questions of application of these kinds are presented. Combine research acoustic brainstem EP and VEMP allows to confirm effectively lesions of acoustical and vestibular ways at brainstem. The conclusion becomes, that this kind of inspection is important for revealing demielinisation and defeats in vestibulospinal tract, that quite often happens at MS, and at estimation of efficiency of treatment

Developmental profiles of the intrinsic properties and synaptic function of auditory neurons in preterm and term baboon neonates.

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Kim, Sei Eun; Lee, Seul Yi; Blanco, Cynthia L; Kim, Jun Hee

2014-08-20

The human fetus starts to hear and undergoes major developmental changes in the auditory system during the third trimester of pregnancy. Although there are significant data regarding development of the auditory system in rodents, changes in intrinsic properties and synaptic function of auditory neurons in developing primate brain at hearing onset are poorly understood. We performed whole-cell patch-clamp recordings of principal neurons in the medial nucleus of trapezoid body (MNTB) in preterm and term baboon brainstem slices to study the structural and functional maturation of auditory synapses. Each MNTB principal neuron received an excitatory input from a single calyx of Held terminal, and this one-to-one pattern of innervation was already formed in preterm baboons delivered at 67% of normal gestation. There was no difference in frequency or amplitude of spontaneous excitatory postsynaptic synaptic currents between preterm and term MNTB neurons. In contrast, the frequency of spontaneous GABA(A)/glycine receptor-mediated inhibitory postsynaptic synaptic currents, which were prevalent in preterm MNTB neurons, was significantly reduced in term MNTB neurons. Preterm MNTB neurons had a higher input resistance than term neurons and fired in bursts, whereas term MNTB neurons fired a single action potential in response to suprathreshold current injection. The maturation of intrinsic properties and dominance of excitatory inputs in the primate MNTB allow it to take on its mature role as a fast and reliable relay synapse. Copyright © 2014 the authors 0270-6474/14/3411399-06$15.00/0.

Serial auditory-evoked potentials in the diagnosis and monitoring of a child with Landau-Kleffner syndrome.

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Plyler, Erin; Harkrider, Ashley W

2013-01-01

A boy, aged 2 1/2 yr, experienced sudden deterioration of speech and language abilities. He saw multiple medical professionals across 2 yr. By almost 5 yr, his vocabulary diminished from 50 words to 4, and he was referred to our speech and hearing center. The purpose of this study was to heighten awareness of Landau-Kleffner syndrome (LKS) and emphasize the importance of an objective test battery that includes serial auditory-evoked potentials (AEPs) to audiologists who often are on the front lines of diagnosis and treatment delivery when faced with a child experiencing unexplained loss of the use of speech and language. Clinical report. Interview revealed a family history of seizure disorder. Normal social behaviors were observed. Acoustic reflexes and otoacoustic emissions were consistent with normal peripheral auditory function. The child could not complete behavioral audiometric testing or auditory processing tests, so serial AEPs were used to examine central nervous system function. Normal auditory brainstem responses, a replicable Na and absent Pa of the middle latency responses, and abnormal slow cortical potentials suggested dysfunction of auditory processing at the cortical level. The child was referred to a neurologist, who confirmed LKS. At age 7 1/2 yr, after 2 1/2 yr of antiepileptic medications, electroencephalographic (EEG) and audiometric measures normalized. Presently, the child communicates manually with limited use of oral information. Audiologists often are one of the first professionals to assess children with loss of speech and language of unknown origin. Objective, noninvasive, serial AEPs are a simple and valuable addition to the central audiometric test battery when evaluating a child with speech and language regression. The inclusion of these tests will markedly increase the chance for early and accurate referral, diagnosis, and monitoring of a child with LKS which is imperative for a positive prognosis. American Academy of Audiology.

Mouse Panx1 Is Dispensable for Hearing Acquisition and Auditory Function

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Veronica Zorzi

2017-11-01

Full Text Available Panx1 forms plasma membrane channels in brain and several other organs, including the inner ear. Biophysical properties, activation mechanisms and modulators of Panx1 channels have been characterized in detail, however the impact of Panx1 on auditory function is unclear due to conflicts in published results. To address this issue, hearing performance and cochlear function of the Panx1−/− mouse strain, the first with a reported global ablation of Panx1, were scrutinized. Male and female homozygous (Panx1−/−, hemizygous (Panx1+/− and their wild type (WT siblings (Panx1+/+ were used for this study. Successful ablation of Panx1 was confirmed by RT-PCR and Western immunoblotting in the cochlea and brain of Panx1−/− mice. Furthermore, a previously validated Panx1-selective antibody revealed strong immunoreactivity in WT but not in Panx1−/− cochleae. Hearing sensitivity, outer hair cell-based “cochlear amplifier” and cochlear nerve function, analyzed by auditory brainstem response (ABR and distortion product otoacoustic emission (DPOAE recordings, were normal in Panx1+/− and Panx1−/− mice. In addition, we determined that global deletion of Panx1 impacts neither on connexin expression, nor on gap-junction coupling in the developing organ of Corti. Finally, spontaneous intercellular Ca2+ signal (ICS activity in organotypic cochlear cultures, which is key to postnatal development of the organ of Corti and essential for hearing acquisition, was not affected by Panx1 ablation. Therefore, our results provide strong evidence that, in mice, Panx1 is dispensable for hearing acquisition and auditory function.

Stance disturbance in multiple sclerosis: brainstem lesions and posturographic assessment

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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.

Auditory Reserve and the Legacy of Auditory Experience

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Erika Skoe

2014-11-01

Full Text Available Musical training during childhood has been linked to more robust encoding of sound later in life. We take this as evidence for an auditory reserve: a mechanism by which individuals capitalize on earlier life experiences to promote auditory processing. We assert that early auditory experiences guide how the reserve develops and is maintained over the lifetime. Experiences that occur after childhood, or which are limited in nature, are theorized to affect the reserve, although their influence on sensory processing may be less long-lasting and may potentially fade over time if not repeated. This auditory reserve may help to explain individual differences in how individuals cope with auditory impoverishment or loss of sensorineural function.

A Review of Norms and Normative Multiagent Systems

Science.gov (United States)

Mahmoud, Moamin A.; Ahmad, Mohd Sharifuddin; Mustapha, Aida

2014-01-01

Norms and normative multiagent systems have become the subjects of interest for many researchers. Such interest is caused by the need for agents to exploit the norms in enhancing their performance in a community. The term norm is used to characterize the behaviours of community members. The concept of normative multiagent systems is used to facilitate collaboration and coordination among social groups of agents. Many researches have been conducted on norms that investigate the fundamental concepts, definitions, classification, and types of norms and normative multiagent systems including normative architectures and normative processes. However, very few researches have been found to comprehensively study and analyze the literature in advancing the current state of norms and normative multiagent systems. Consequently, this paper attempts to present the current state of research on norms and normative multiagent systems and propose a norm's life cycle model based on the review of the literature. Subsequently, this paper highlights the significant areas for future work. PMID:25110739

A review of norms and normative multiagent systems.

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Mahmoud, Moamin A; Ahmad, Mohd Sharifuddin; Yusoff, Mohd Zaliman Mohd; Mustapha, Aida

2014-01-01

Norms and normative multiagent systems have become the subjects of interest for many researchers. Such interest is caused by the need for agents to exploit the norms in enhancing their performance in a community. The term norm is used to characterize the behaviours of community members. The concept of normative multiagent systems is used to facilitate collaboration and coordination among social groups of agents. Many researches have been conducted on norms that investigate the fundamental concepts, definitions, classification, and types of norms and normative multiagent systems including normative architectures and normative processes. However, very few researches have been found to comprehensively study and analyze the literature in advancing the current state of norms and normative multiagent systems. Consequently, this paper attempts to present the current state of research on norms and normative multiagent systems and propose a norm's life cycle model based on the review of the literature. Subsequently, this paper highlights the significant areas for future work.

Optimal technique of linear accelerator-based stereotactic radiosurgery for tumors adjacent to brainstem.

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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 linear accelerator is only 1 modality can to establish for SRS treatment. Based on statistical evidence retrospectively, we recommend VMAT as the optimal technique for delivering treatment to tumors adjacent to brainstem. Copyright © 2016 American Association of Medical Dosimetrists. All rights reserved.

Assessment of children with suspected auditory processing disorder: a factor analysis study.

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Ahmmed, Ansar U; Ahmmed, Afsara A; Bath, Julie R; Ferguson, Melanie A; Plack, Christopher J; Moore, David R

2014-01-01

To identify the factors that may underlie the deficits in children with listening difficulties, despite normal pure-tone audiograms. These children may have auditory processing disorder (APD), but there is no universally agreed consensus as to what constitutes APD. The authors therefore refer to these children as children with suspected APD (susAPD) and aim to clarify the role of attention, cognition, memory, sensorimotor processing speed, speech, and nonspeech auditory processing in susAPD. It was expected that a factor analysis would show how nonauditory and supramodal factors relate to auditory behavioral measures in such children with susAPD. This would facilitate greater understanding of the nature of listening difficulties, thus further helping with characterizing APD and designing multimodal test batteries to diagnose APD. Factor analysis of outcomes from 110 children (68 male, 42 female; aged 6 to 11 years) with susAPD on a widely used clinical test battery (SCAN-C) and a research test battery (MRC Institute of Hearing Research Multi-center Auditory Processing "IMAP"), that have age-based normative data. The IMAP included backward masking, simultaneous masking, frequency discrimination, nonverbal intelligence, working memory, reading, alerting attention and motor reaction times to auditory and visual stimuli. SCAN-C included monaural low-redundancy speech (auditory closure and speech in noise) and dichotic listening tests (competing words and competing sentences) that assess divided auditory attention and hence executive attention. Three factors were extracted: "general auditory processing," "working memory and executive attention," and "processing speed and alerting attention." Frequency discrimination, backward masking, simultaneous masking, and monaural low-redundancy speech tests represented the "general auditory processing" factor. Dichotic listening and the IMAP cognitive tests (apart from nonverbal intelligence) were represented in the "working

Stereotactic radiosurgery for brainstem metastases: Survival, tumor control, and patient outcomes

International Nuclear Information System (INIS)

Hussain, Aamir; Brown, Paul D.; Stafford, Scott L.; Pollock, Bruce E.

2007-01-01

Purpose: Patients with brainstem metastases have limited treatment options. In this study, we reviewed outcomes after stereotactic radiosurgery (SRS) in the management of patients with brainstem metastases. Methods and Materials: Records were reviewed of 22 consecutive patients presenting with brainstem metastases who underwent SRS. The most frequent primary malignancy was the lung (n = 11), followed by breast (n = 3) and kidney (n = 2). Three patients (14%) also underwent whole-brain radiation therapy (WBRT). The median tumor volume was 0.9 mL (range, 0.1-3.3 mL); the median tumor margin dose was 16 Gy (range, 14-23 Gy). Results: Median survival time after SRS was 8.5 months. Although local tumor control was achieved in all patients with imaging follow-up (n = 19), 5 patients died from development and progression of new brain metastases. Two patients (9%) had symptom improvement after SRS, whereas 1 patient (5%) developed a new hemiparesis after SRS. Conclusions: Radiosurgery is safe and provides a high local tumor control rate for patients with small brainstem metastases. Patients with limited systemic disease and good performance status should be strongly considered for SRS

Inquiry and the normative aspect in learning

DEFF Research Database (Denmark)

Wiberg, Merete

as the interplay between intentions and life-story of the individual and culture and community. The theory of inquiry in the philosophy of Dewey offers an understanding of processes of learning as transformation from an indeterminate to a determinate situation. Furthermore, the normative aspect of learning......“Inquiry and the normative aspect of learning” In the paper it will be argued that the normative aspect of learning is to be found in the interplay between individual and world when the individual in an inquiring process tries to come to terms with the world. Normativity in learning is seen...

Effect Of Electromagnetic Waves Emitted From Mobile Phone On Brain Stem Auditory Evoked Potential In Adult Males.

Science.gov (United States)

Singh, K

2015-01-01

Mobile phone (MP) is commonly used communication tool. Electromagnetic waves (EMWs) emitted from MP may have potential health hazards. So, it was planned to study the effect of electromagnetic waves (EMWs) emitted from the mobile phone on brainstem auditory evoked potential (BAEP) in male subjects in the age group of 20-40 years. BAEPs were recorded using standard method of 10-20 system of electrode placement and sound click stimuli of specified intensity, duration and frequency.Right ear was exposed to EMW emitted from MP for about 10 min. On comparison of before and after exposure to MP in right ear (found to be dominating ear), there was significant increase in latency of II, III (p potential.

Characterising Ageing in the Human Brainstem Using Quantitative Multimodal MRI Analysis

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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.

Normative values for a functional capacity evaluation.

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Soer, Remko; van der Schans, Cees P; Geertzen, Jan H; Groothoff, Johan W; Brouwer, Sandra; Dijkstra, Pieter U; Reneman, Michiel F

2009-10-01

Soer R, van der Schans CP, Geertzen JH, Groothoff JW, Brouwer S, Dijkstra PU, Reneman MF. Normative values for a functional capacity evaluation. To establish normative values for a functional capacity evaluation (FCE) of healthy working subjects. Descriptive. Rehabilitation center. Healthy working subjects (N=701; 448 men, 253 women) between 20 and 60 years of age, working in more than 180 occupations. Subjects performed a 2-hour FCE consisting of 12 work-related tests. Subjects were classified into categories based on physical demands according to the Dictionary of Occupational Titles. Means, ranges, SDs, and percentiles were provided for normative values of FCE, and a regression analysis for outcome of the 12 tests was performed. Normative FCE values were established for 4 physical demand categories. The normative values enable comparison of patients' performances to these values. If a patient's performance exceeds the lowest scores in his/her corresponding demand category, then the patient's capacity is very likely to be sufficient to meet the workload. Further, clinicians can make more precise return-to-work recommendations and set goals for rehabilitation programs. A comparison of the normative values can be useful to the fields of rehabilitation, occupational, and insurance medicine. Further research is needed to test the validity of the normative values with respect to workplace assessments and return-to-work recommendations.

Mechanisms of spectral and temporal integration in the mustached bat inferior colliculus

Science.gov (United States)

Wenstrup, Jeffrey James; Nataraj, Kiran; Sanchez, Jason Tait

2012-01-01

This review describes mechanisms and circuitry underlying combination-sensitive response properties in the auditory brainstem and midbrain. Combination-sensitive neurons, performing a type of auditory spectro-temporal integration, respond to specific, properly timed combinations of spectral elements in vocal signals and other acoustic stimuli. While these neurons are known to occur in the auditory forebrain of many vertebrate species, the work described here establishes their origin in the auditory brainstem and midbrain. Focusing on the mustached bat, we review several major findings: (1) Combination-sensitive responses involve facilitatory interactions, inhibitory interactions, or both when activated by distinct spectral elements in complex sounds. (2) Combination-sensitive responses are created in distinct stages: inhibition arises mainly in lateral lemniscal nuclei of the auditory brainstem, while facilitation arises in the inferior colliculus (IC) of the midbrain. (3) Spectral integration underlying combination-sensitive responses requires a low-frequency input tuned well below a neuron's characteristic frequency (ChF). Low-ChF neurons in the auditory brainstem project to high-ChF regions in brainstem or IC to create combination sensitivity. (4) At their sites of origin, both facilitatory and inhibitory combination-sensitive interactions depend on glycinergic inputs and are eliminated by glycine receptor blockade. Surprisingly, facilitatory interactions in IC depend almost exclusively on glycinergic inputs and are largely independent of glutamatergic and GABAergic inputs. (5) The medial nucleus of the trapezoid body (MNTB), the lateral lemniscal nuclei, and the IC play critical roles in creating combination-sensitive responses. We propose that these mechanisms, based on work in the mustached bat, apply to a broad range of mammals and other vertebrates that depend on temporally sensitive integration of information across the audible spectrum. PMID:23109917

Normative Virtue Theory in Theological Ethics

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Nicholas Austin

2017-09-01

Full Text Available What place is there for virtue theory in theological ethics? Many question the normative significance of virtue theory in theological ethics today, leaving it to rule-based ethics to provide action-guidance. There are three key objections to the normativity of virtue theory: that virtue theory is about agents rather than actions, that virtue theory has nothing to say directly about the morality of actions, and that the virtues are too vague to be of normative or action-guiding significance. This essay, drawing on Thomas Aquinas’s account of virtue, challenges these perceptions and argues for a genuinely normative, action-guiding virtue theory within theological ethics. Theological ethics, in turn, can contribute to virtue theory, especially by its emphasis on the ecstatic nature of mature moral virtue, and through its reflection on the virtue of spiritual discernment.

Evidence that BDNF regulates heart rate by a mechanism involving increased brainstem parasympathetic neuron excitability

OpenAIRE

Wan, Ruiqian; Weigand, Letitia A.; Bateman, Ryan; Griffioen, Kathleen; Mendelowitz, David; Mattson, Mark P.

2014-01-01

Autonomic control of heart rate is mediated by cardioinhibitory parasympathetic cholinergic neurons located in the brainstem and stimulatory sympathetic noradrenergic neurons. During embryonic development the survival and cholinergic phenotype of brainstem autonomic neurons is promoted by brain-derived neurotrophic factor (BDNF). We now provide evidence that BDNF regulates heart rate by a mechanism involving increased brainstem cardioinhibitory parasympathetic activity. Mice with a BDNF haplo...

The Central Auditory Processing Kit[TM]. Book 1: Auditory Memory [and] Book 2: Auditory Discrimination, Auditory Closure, and Auditory Synthesis [and] Book 3: Auditory Figure-Ground, Auditory Cohesion, Auditory Binaural Integration, and Compensatory Strategies.

Science.gov (United States)

Mokhemar, Mary Ann

This kit for assessing central auditory processing disorders (CAPD), in children in grades 1 through 8 includes 3 books, 14 full-color cards with picture scenes, and a card depicting a phone key pad, all contained in a sturdy carrying case. The units in each of the three books correspond with auditory skill areas most commonly addressed in…

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.

Auditory Perceptual Abilities Are Associated with Specific Auditory Experience

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Yael Zaltz

2017-11-01

Full Text Available The extent to which auditory experience can shape general auditory perceptual abilities is still under constant debate. Some studies show that specific auditory expertise may have a general effect on auditory perceptual abilities, while others show a more limited influence, exhibited only in a relatively narrow range associated with the area of expertise. The current study addresses this issue by examining experience-dependent enhancement in perceptual abilities in the auditory domain. Three experiments were performed. In the first experiment, 12 pop and rock musicians and 15 non-musicians were tested in frequency discrimination (DLF, intensity discrimination, spectrum discrimination (DLS, and time discrimination (DLT. Results showed significant superiority of the musician group only for the DLF and DLT tasks, illuminating enhanced perceptual skills in the key features of pop music, in which miniscule changes in amplitude and spectrum are not critical to performance. The next two experiments attempted to differentiate between generalization and specificity in the influence of auditory experience, by comparing subgroups of specialists. First, seven guitar players and eight percussionists were tested in the DLF and DLT tasks that were found superior for musicians. Results showed superior abilities on the DLF task for guitar players, though no difference between the groups in DLT, demonstrating some dependency of auditory learning on the specific area of expertise. Subsequently, a third experiment was conducted, testing a possible influence of vowel density in native language on auditory perceptual abilities. Ten native speakers of German (a language characterized by a dense vowel system of 14 vowels, and 10 native speakers of Hebrew (characterized by a sparse vowel system of five vowels, were tested in a formant discrimination task. This is the linguistic equivalent of a DLS task. Results showed that German speakers had superior formant

Dangerous Dogs, Constructivism and Normative Implications

DEFF Research Database (Denmark)

Hansen, Allan Dreyer

The paper argues that even though there is no necessary link between constructivism and specific norms, constructivism opens a space for normativity and can be articulated with specific normative or political programs. The argument is based on Laclau’s deconstructive constructivism, but instead...

Unbound Bilirubin and Auditory Neuropathy Spectrum Disorder in Late Preterm and Term Infants with Severe Jaundice.

Science.gov (United States)

Amin, Sanjiv B; Wang, Hongyue; Laroia, Nirupama; Orlando, Mark

2016-06-01

This study evaluates whether unbound bilirubin is a better predictor of auditory neuropathy spectrum disorder (ANSD) than total serum bilirubin (TSB) or the bilirubin:albumin molar ratio (BAMR) in late preterm and term neonates with severe jaundice (TSB ≥20 mg/dL or TSB that met exchange transfusion criteria). Infants ≥34 weeks' gestation with severe jaundice during the first 2 weeks of life were eligible for the prospective observational study. A comprehensive auditory evaluation was performed within 72 hours of peak TSB. ANSD was defined as absent or abnormal auditory brainstem evoked response waveform morphology at 80-decibel click intensity in the presence of normal outer hair cell function. TSB, serum albumin, and unbound bilirubin were measured using the colorimetric, bromocresol green, and modified peroxidase method, respectively. Five of 44 infants developed ANSD. By logistic regression, peak unbound bilirubin but not peak TSB or peak BAMR was associated with ANSD (OR, 4.6; 95% CI, 1.6-13.5; P = .002). On comparing receiver operating characteristic curves, the area under the curve for unbound bilirubin (0.92) was significantly greater (P = .04) compared with the area under the curve for TSB (0.50) or BAMR (0.62). Unbound bilirubin is a more sensitive and specific predictor of ANSD than TSB or BAMR in late preterm and term infants with severe jaundice. Copyright © 2016 Elsevier Inc. All rights reserved.

Correlation of Acute and Late Brainstem Toxicities With Dose-Volume Data for Pediatric Patients With Posterior Fossa Malignancies

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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

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.

Normative Cognition in Culture and Religion

DEFF Research Database (Denmark)

Jensen, Jeppe Sinding

2013-01-01

"Normative Cognition" is a theoretical model of human cognition as driven, modulated and governed by symbolically mediated inter-subjective norms and conventions......"Normative Cognition" is a theoretical model of human cognition as driven, modulated and governed by symbolically mediated inter-subjective norms and conventions...

Cortical evoked potentials to an auditory illusion: binaural beats.

Science.gov (United States)

Pratt, Hillel; Starr, Arnold; Michalewski, Henry J; Dimitrijevic, Andrew; Bleich, Naomi; Mittelman, Nomi

2009-08-01

To define brain activity corresponding to an auditory illusion of 3 and 6Hz binaural beats in 250Hz or 1000Hz base frequencies, and compare it to the sound onset response. Event-Related Potentials (ERPs) were recorded in response to unmodulated tones of 250 or 1000Hz to one ear and 3 or 6Hz higher to the other, creating an illusion of amplitude modulations (beats) of 3Hz and 6Hz, in base frequencies of 250Hz and 1000Hz. Tones were 2000ms in duration and presented with approximately 1s intervals. Latency, amplitude and source current density estimates of ERP components to tone onset and subsequent beats-evoked oscillations were determined and compared across beat frequencies with both base frequencies. All stimuli evoked tone-onset P(50), N(100) and P(200) components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude with the low base frequency and to the low beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left lateral and inferior temporal lobe areas in all stimulus conditions. Onset-evoked components were not different across stimulus conditions; P(50) had significantly different sources than the beats-evoked oscillations; and N(100) and P(200) sources located to the same temporal lobe regions as beats-evoked oscillations, but were bilateral and also included frontal and parietal contributions. Neural activity with slightly different volley frequencies from left and right ear converges and interacts in the central auditory brainstem pathways to generate beats of neural activity to modulate activities in the left temporal lobe, giving rise to the illusion of binaural beats. Cortical potentials recorded to binaural beats are distinct from onset responses. Brain activity corresponding to an auditory illusion of low frequency beats can be recorded from the scalp.

Implicit normativity in scientific advice

DEFF Research Database (Denmark)

Folker, Anna Paldam; Andersen, Hanne; Sandøe, Peter

2008-01-01

This paper focuses on implicit normative considerations underlying scientific advice-those normative questions, decisions, or issues that scientific advisers and the general public are not fully aware of but that nevertheless have implications for the character of the advice given. Using...... nutritional science as an example, we identify three such implicit normative issues. The first concerns the aim of scientific advice: whether it is about avoiding harm or promoting good. The second concerns the intended beneficiaries of the advice: whether advice should be framed to benefit the society...... as a whole or with special concern for the most vulnerable members of the population. The third consideration involves scientific advisers' attempts to balance the strengths of the scientific evidence with the expected consequences of scientific advice. We hope to promote more explicit discussion...

Right-sided dominance of the bilateral vestibular system in the upper brainstem and thalamus.

Science.gov (United States)

Dieterich, Marianne; Kirsch, V; Brandt, T

2017-10-01

MRI diffusion tensor imaging tractography was performed on the bilateral vestibular brainstem pathways, which run from the vestibular nuclei via the paramedian and posterolateral thalamic subnuclei to the parieto-insular vestibular cortex. Twenty-one right-handed healthy subjects participated. Quantitative analysis revealed a rope-ladder-like system of vestibular pathways in the brainstem with crossings at pontine and mesencephalic levels. Three structural types of right-left fiber distributions could be delineated: (1) evenly distributed pathways at the lower pontine level from the vestibular nuclei to the pontine crossing, (2) a moderate, pontomesencephalic right-sided lateralization between the pontine and mesencephalic crossings, and (3) a further increase of the right-sided lateralization above the mesencephalic crossing leading to the thalamic vestibular subnuclei. The increasing lateralization along the brainstem was the result of an asymmetric number of pontine and mesencephalic crossing fibers which was higher for left-to-right crossings. The dominance of the right vestibular meso-diencephalic circuitry in right-handers corresponds to the right-hemispheric dominance of the vestibular cortical network. The structural asymmetry apparent in the upper brainstem might be interpreted in relation to the different functions of the vestibular system depending on their anatomical level: a symmetrical sensorimotor reflex control of eye, head, and body mediated by the lower brainstem; a lateralized right-sided upper brainstem-thalamic function as part of the dominant right-sided cortical/subcortical vestibular system that enables a global percept of body motion and orientation in space.

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.

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.

Stereotactic radiosurgery for deep intracranial arteriovenous malformations, part 1: Brainstem arteriovenous malformations.

Science.gov (United States)

Cohen-Inbar, Or; Ding, Dale; Chen, Ching-Jen; Sheehan, Jason P

2016-02-01

The management of brainstem arteriovenous malformations (AVM) are one of the greatest challenges encountered by neurosurgeons. Brainstem AVM have a higher risk of hemorrhage compared to AVM in other locations, and rupture of these lesions commonly results in devastating neurological morbidity and mortality. The potential morbidity associated with currently available treatment modalities further compounds the complexity of decision making for affected patients. Stereotactic radiosurgery (SRS) has an important role in the management of brainstem AVM. SRS offers acceptable obliteration rates with lower risks of hemorrhage occurring during the latency period. Complex nidal architecture requires a multi-disciplinary treatment approach. Nidi partly involving subpial/epipial regions of the dorsal midbrain or cerebellopontine angle should be considered for a combination of endovascular embolization, micro-surgical resection and SRS. Considering the fact that incompletely obliterated lesions (even when reduced in size) could still cause lethal hemorrhages, additional treatment, including repeat SRS and surgical resection should be considered when complete obliteration is not achieved by first SRS. Patients with brainstem AVM require continued clinical and radiological observation and follow-up after SRS, well after angiographic obliteration has been confirmed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Total and regional brain volumes in a population-based normative sample from 4 to 18 years: the NIH MRI Study of Normal Brain Development.

Science.gov (United States)

2012-01-01

Using a population-based sampling strategy, the National Institutes of Health (NIH) Magnetic Resonance Imaging Study of Normal Brain Development compiled a longitudinal normative reference database of neuroimaging and correlated clinical/behavioral data from a demographically representative sample of healthy children and adolescents aged newborn through early adulthood. The present paper reports brain volume data for 325 children, ages 4.5-18 years, from the first cross-sectional time point. Measures included volumes of whole-brain gray matter (GM) and white matter (WM), left and right lateral ventricles, frontal, temporal, parietal and occipital lobe GM and WM, subcortical GM (thalamus, caudate, putamen, and globus pallidus), cerebellum, and brainstem. Associations with cross-sectional age, sex, family income, parental education, and body mass index (BMI) were evaluated. Key observations are: 1) age-related decreases in lobar GM most prominent in parietal and occipital cortex; 2) age-related increases in lobar WM, greatest in occipital, followed by the temporal lobe; 3) age-related trajectories predominantly curvilinear in females, but linear in males; and 4) small systematic associations of brain tissue volumes with BMI but not with IQ, family income, or parental education. These findings constitute a normative reference on regional brain volumes in children and adolescents.

Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

DEFF Research Database (Denmark)

Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

2017-01-01

-spontaneous rate fibers results in a faster recovery of wave-V latency as the slow contribution of these fibers is reduced. Results showed that in young audiometrically normal listeners, a larger change in wave-V latency with increasing masker-to-probe interval was related to a greater effect of a preceding masker......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

Formal and Informal Normative Beliefs Regarding Purchasing and Using Condoms

OpenAIRE

樋口, 匡貴; 中村, 菜々子

2009-01-01

Properly using condoms is one of the most effective types of protection against HIV. To clarify the contents of normative beliefs regarding purchasing and using condoms, 390 undergraduate student volunteers were surveyed. The exploratory and confirmatory factor analyses revealed that both males and females held two types of normative beliefs, namely formal normative beliefs and informal normative beliefs, regarding purchasing and using condoms. Formal normative beliefs were concerned with the...

Further evidence for a fluid pathway during bone conduction auditory stimulation.

Science.gov (United States)

Sohmer, Haim; Freeman, Sharon

2004-07-01

This study was designed to evaluate the suggestion that during bone vibrator stimulation on skull bone (bone conduction auditory stimulation), a major connection between the site of the bone vibrator and the inner ear is a fluid pathway. A series of experiments were conducted on pairs of animals (rats or guinea pigs). The cranial cavities of each pair of animals were coupled by means of a saline filled plastic tube sealed into a craniotomy in the skull of each animal. In response to bone conduction click stimulation to the skull bone of animal I, auditory nerve-brainstem evoked responses could be recorded in animal II. Various procedures showed that these responses were initiated in animal II in response to audio-frequency sound pressures generated within the cranial cavity of animal I by the bone conduction stimulation and transferred to the cranial cavity of animal II through the fluid in the plastic tube: they were not responses to air conducted sounds generated by the bone vibrator, were not induced in animal II by vibrations conveyed to it by the plastic tube and were not electrically conducted activity from animal I. Exposing the fluid in the tube to air was not accompanied by any change in threshold. These experiments confirm that during bone conduction stimulation on the skull, audio-frequency sound pressures (alternating condensations and rarefactions) can be conveyed by a fluid pathway to the cochlea and stimulate it.

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.

Ebselen attenuates cisplatin-induced ROS generation through Nrf2 activation in auditory cells.

Science.gov (United States)

Kim, Se-Jin; Park, Channy; Han, A Lum; Youn, Myung-Ja; Lee, Jeong-Han; Kim, Yunha; Kim, Eun-Sook; Kim, Hyung-Jin; Kim, Jin-Kyung; Lee, Ho-Kyun; Chung, Sang-Young; So, Hongseob; Park, Raekil

2009-05-01

Ebselen, an organoselenium compound that acts as a glutathione peroxidase mimetic, has been demonstrated to possess antioxidant and anti-inflammatory activities. However, the molecular mechanism underlying this effect is not fully understood in auditory cells. The purpose of the present study is to investigate the protective effect of ebselen against cisplatin-induced toxicity in HEI-OC1 auditory cells, organotypic cultures of cochlear explants from two-day postnatal rats (P(2)) and adult Balb/C mice. Pretreatment with ebselen ameliorated apoptotic death induced by cisplatin in HEI-OC1 cells and organotypic cultures of Corti's organ. Ebselen pretreatment also significantly suppressed cisplatin-induced increases in intracellular reactive oxygen species (ROS), intracellular reactive nitrogen species (RNS) and lipid peroxidation levels. Ebselen dose-dependently increased the expression level of an antioxidant response element (ARE)-luciferase reporter in HEI-OC1 cells through the translocation of Nrf2 into the nucleus. Furthermore, we found that pretreatment with ebselen significantly restored Nrf2 function, whereas it ameliorated the cytotoxicity of cisplatin in cells transfectants with either a pcDNA3.1 (control) or a DN-Nrf2 (dominant-negative) plasmid. We also observed that Nrf2 activation by ebselen increased the expression of phase II antioxidant genes, including heme oxygenase (HO-1), NAD(P)H:quinine oxidoreductase, and gamma-glutamylcysteine synthetase (gamma-GCS). Treatment with ebselen resulted in an increased expression of HO-1 and intranuclear Nrf2 in hair cells of organotypic cultured cochlea. After intraperitoneal injection with cisplatin, auditory brainstem responses (ABRs) threshold was measured on 8th day in Balb/C mice. ABR threshold shift was marked occurred in mice injected with cisplatin (16 mg/kg, n=5; Click and 8-kHz stimuli, pebselen was not significantly changed. These results suggest that ebselen activates the Nrf2-ARE signaling pathway

Auditory Association Cortex Lesions Impair Auditory Short-Term Memory in Monkeys

Science.gov (United States)

Colombo, Michael; D'Amato, Michael R.; Rodman, Hillary R.; Gross, Charles G.

1990-01-01

Monkeys that were trained to perform auditory and visual short-term memory tasks (delayed matching-to-sample) received lesions of the auditory association cortex in the superior temporal gyrus. Although visual memory was completely unaffected by the lesions, auditory memory was severely impaired. Despite this impairment, all monkeys could discriminate sounds closer in frequency than those used in the auditory memory task. This result suggests that the superior temporal cortex plays a role in auditory processing and retention similar to the role the inferior temporal cortex plays in visual processing and retention.

Age-related hearing loss: Aquaporin 4 gene expression changes in the mouse cochlea and auditory midbrain

Science.gov (United States)

Christensen, Nathan; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D.

2009-01-01

Presbycusis – age-related hearing loss, is the number one communication disorder, and one of the top three chronic medical conditions of our aged population. Aquaporins, particularly aquaporin 4 (Aqp4), are membrane proteins with important roles in water and ion flux across cell membranes, including cells of the inner ear and pathways of the brain used for hearing. To more fully understand the biological bases of presbycusis, 39 CBA mice, a well-studied animal model of presbycusis, underwent non-invasive hearing testing as a function of sound frequency (auditory brainstem response – ABR thresholds, and distortion-product otoacoustic emission – DPOAE magnitudes), and were clustered into four groups based on age and hearing ability. Aqp4 gene expression, as determined by genechip microarray analysis and quantitative real-time PCR, was compared to the young adult control group in the three older groups: middle aged with good hearing, old age with mild presbycusis, and old age with severe presbycusis. Linear regression and ANOVA showed statistically significant changes in Aqp4 gene expression and ABR and DPOAE hearing status in the cochlea and auditory midbrain – inferior colliculus. Down-regulation in the cochlea was seen, and an initial down-, then up-regulation was discovered for the inferior colliculus Aqp4 expression. It is theorized that these changes in Aqp4 gene expression represent an age-related disruption of ion flux in the fluids of the cochlea that are responsible for ionic gradients underlying sound transduction in cochlear hair cells necessary for hearing. In regard to central auditory processing at the level of the auditory midbrain, aquaporin gene expression changes may affect neurotransmitter cycling involving supporting cells, thus impairing complex sound neural processing with age. PMID:19070604

Auditory hallucinations.

Science.gov (United States)

Blom, Jan Dirk

2015-01-01

Auditory hallucinations constitute a phenomenologically rich group of endogenously mediated percepts which are associated with psychiatric, neurologic, otologic, and other medical conditions, but which are also experienced by 10-15% of all healthy individuals in the general population. The group of phenomena is probably best known for its verbal auditory subtype, but it also includes musical hallucinations, echo of reading, exploding-head syndrome, and many other types. The subgroup of verbal auditory hallucinations has been studied extensively with the aid of neuroimaging techniques, and from those studies emerges an outline of a functional as well as a structural network of widely distributed brain areas involved in their mediation. The present chapter provides an overview of the various types of auditory hallucination described in the literature, summarizes our current knowledge of the auditory networks involved in their mediation, and draws on ideas from the philosophy of science and network science to reconceptualize the auditory hallucinatory experience, and point out directions for future research into its neurobiologic substrates. In addition, it provides an overview of known associations with various clinical conditions and of the existing evidence for pharmacologic and non-pharmacologic treatments. © 2015 Elsevier B.V. All rights reserved.

Social Institutions as Tools in Normative Cognition

DEFF Research Database (Denmark)

Jensen, Jeppe Sinding

Social institutions are normative cognitive tools, the functions of which should be an important subject in cognitive anthropology......Social institutions are normative cognitive tools, the functions of which should be an important subject in cognitive anthropology...

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.

NORMATIVE MODERATORS OF IMPULSE BUYING BEHAVIOR

Directory of Open Access Journals (Sweden)

Danes Jaya Negara

2003-01-01

Full Text Available Prior research has presented the moderating role of normative evaluations in the relationship between the impulsive buying trait and consumers’ buying behaviors. In this article the authors show that consumer tendency to buy something spontaneous, unreflectively and immediately can be perceived as a factor which describes buying impulsiveness. This article also shows conceptual and empirical evidence that there is some support for the moderating role of normative evaluations in the relationship between buying impulsiveness and impulse buying behaviors. Significance occurs when consumers believe that act on impulse is suitable. The result suggests that consumers’ normative evaluation can moderate the link between the trait and behavioral aspects of impulse buying.

Auditory short-term memory in the primate auditory cortex.

Science.gov (United States)

Scott, Brian H; Mishkin, Mortimer

2016-06-01

Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory. Published by Elsevier B.V.

Two Notions of Epistemic Normativity

DEFF Research Database (Denmark)

Klausen, Søren Harnow

2009-01-01

Although the dominant view of epistemic normativity is an extreme form of deontology, it is argued that there is no good reason for not also adopting a complementary consequentialist notion, which can be put to use in applied epistemology.......Although the dominant view of epistemic normativity is an extreme form of deontology, it is argued that there is no good reason for not also adopting a complementary consequentialist notion, which can be put to use in applied epistemology....

[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.

Conductive Hearing Loss Has Long-Lasting Structural and Molecular Effects on Presynaptic and Postsynaptic Structures of Auditory Nerve Synapses in the Cochlear Nucleus.

Science.gov (United States)

Clarkson, Cheryl; Antunes, Flora M; Rubio, Maria E

2016-09-28

Sound deprivation by conductive hearing loss increases hearing thresholds, but little is known about the response of the auditory brainstem during and after conductive hearing loss. Here, we show in young adult rats that 10 d of monaural conductive hearing loss (i.e., earplugging) leads to hearing deficits that persist after sound levels are restored. Hearing thresholds in response to clicks and frequencies higher than 8 kHz remain increased after a 10 d recovery period. Neural output from the cochlear nucleus measured at 10 dB above threshold is reduced and followed by an overcompensation at the level of the lateral lemniscus. We assessed whether structural and molecular substrates at auditory nerve (endbulb of Held) synapses in the cochlear nucleus could explain these long-lasting changes in hearing processing. During earplugging, vGluT1 expression in the presynaptic terminal decreased and synaptic vesicles were smaller. Together, there was an increase in postsynaptic density (PSD) thickness and an upregulation of GluA3 AMPA receptor subunits on bushy cells. After earplug removal and a 10 d recovery period, the density of synaptic vesicles increased, vesicles were also larger, and the PSD of endbulb synapses was larger and thicker. The upregulation of the GluA3 AMPAR subunit observed during earplugging was maintained after the recovery period. This suggests that GluA3 plays a role in plasticity in the cochlear nucleus. Our study demonstrates that sound deprivation has long-lasting alterations on structural and molecular presynaptic and postsynaptic components at the level of the first auditory nerve synapse in the auditory brainstem. Despite being the second most prevalent form of hearing loss, conductive hearing loss and its effects on central synapses have received relatively little attention. Here, we show that 10 d of monaural conductive hearing loss leads to an increase in hearing thresholds, to an increased central gain upstream of the cochlear nucleus at

Herpetic brainstem encephalitis: report of a post-mortem case studied electron microscopically and immunohisiochemically

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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.

169 CONTENT NORMATIVITY AND THE INTERDEPENDENCY OF ...

African Journals Online (AJOL)

Tracie1

INTERDEPENDENCY OF BELIEF AND DESIRE. Seyed Ali ... attriЛutions are constitutively normative since “it is a condition on ... the concept of Лelief is constitutively normative since .... according to the definition (14) the concept of content.

Speech-in-Noise Tests and Supra-threshold Auditory Evoked Potentials as Metrics for Noise Damage and Clinical Trial Outcome Measures.

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Le Prell, Colleen G; Brungart, Douglas S

2016-09-01

In humans, the accepted clinical standards for detecting hearing loss are the behavioral audiogram, based on the absolute detection threshold of pure-tones, and the threshold auditory brainstem response (ABR). The audiogram and the threshold ABR are reliable and sensitive measures of hearing thresholds in human listeners. However, recent results from noise-exposed animals demonstrate that noise exposure can cause substantial neurodegeneration in the peripheral auditory system without degrading pure-tone audiometric thresholds. It has been suggested that clinical measures of auditory performance conducted with stimuli presented above the detection threshold may be more sensitive than the behavioral audiogram in detecting early-stage noise-induced hearing loss in listeners with audiometric thresholds within normal limits. Supra-threshold speech-in-noise testing and supra-threshold ABR responses are reviewed here, given that they may be useful supplements to the behavioral audiogram for assessment of possible neurodegeneration in noise-exposed listeners. Supra-threshold tests may be useful for assessing the effects of noise on the human inner ear, and the effectiveness of interventions designed to prevent noise trauma. The current state of the science does not necessarily allow us to define a single set of best practice protocols. Nonetheless, we encourage investigators to incorporate these metrics into test batteries when feasible, with an effort to standardize procedures to the greatest extent possible as new reports emerge.

Bayesian segmentation of brainstem structures in MRI

DEFF Research Database (Denmark)

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

2015-01-01

the brainstem structures in novel scans. Thanks to the generative nature of the scheme, the segmentation method is robust to changes in MRI contrast or acquisition hardware. Using cross validation, we show that the algorithm can segment the structures in previously unseen T1 and FLAIR scans with great accuracy...

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

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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.

Un-National Normative Justification for European Union Foreign Policy

DEFF Research Database (Denmark)

Manners, Ian

2011-01-01

The European Union's foreign policy has traditionally been described in terms of national, supranational or transnational interests rather than being justified in terms of normative political theory. As European Commissioner Bonino declared over a decade ago, such differentiation between...... descriptive interests and normative ethics is unsustainable in European Union (EU) foreign policy. What are needed are normative justifications that can help inform political choices about foreign policy in the EU's democratic political order. In other words, what are the un-national normative justifications...

Auditory and language outcomes in children with unilateral hearing loss.

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Fitzpatrick, Elizabeth M; Gaboury, Isabelle; Durieux-Smith, Andrée; Coyle, Doug; Whittingham, JoAnne; Nassrallah, Flora

2018-03-13

measures, children with UHL performed poorer than those in the mild bilateral and normal hearing study groups. All children with hearing loss performed at lower levels compared to the normal hearing control group. However, mean standard scores for the normal hearing group in this study were above normative means for the language measures. In particular, children with UHL showed gaps compared to the normal hearing control group in functional auditory listening and in receptive and expressive language skills (three quarters of one standard deviation below) at age 48 months. Their performance in receptive vocabulary and speech production was not significantly different from that of their hearing peers. Even when identified in the first months of life, children with UHL show a tendency to lag behind their normal hearing peers in functional auditory listening and in receptive and expressive language development. Copyright © 2018 Elsevier B.V. All rights reserved.

Normativity and deflationary theories of truth

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Bruno Mölder

2008-12-01

Full Text Available It has been argued that deflationary theories of truth stumble over the normativity of truth. This paper maintains that the normativity objection does not pose problems to at least one version of deflationism, minimalism. The rest of the paper discusses truth-related norms, showing that either they do not hold or they are not troublesome for deflationism.

Mosaic Evolution of Brainstem Motor Nuclei in Catarrhine Primates

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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.

Specific brainstem and cortico-spinal reflex abnormalities in coexisting essential tremor and Parkinson's disease (ET-PD).

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Yavuz, D; Gündüz, A; Ertan, S; Apaydın, H; Şifoğlu, A; Kiziltan, G; Kiziltan, M E

2015-05-01

We aimed to analyze functional changes at brainstem and spinal levels in essential tremor (ET), Parkinson's disease (PD) and coexisting essential tremor and Parkinson's disease (ET-PD). Age- and gender-matched patients with tremor (15 ET, 7 ET with resting tremor, 25 ET-PD and 10 PD) and 12 healthy subjects were enrolled in the study. Diagnosis was established according to standardized clinical criteria. Electrophysiological studies included blink reflex (BR), auditory startle reaction (ASR) and long latency reflex (LLR). Blink reflex was normal and similar in all groups. Probability of ASR was significantly lower in ET-PD group whereas it was similar to healthy subjects in ET and PD (PET, PD and ET-PD groups. LLR III was far more common in the PD group (n=3, 13.6% in ET; n=4, 16.0% in ET-PD and n=7, 46.7% in PD; p=0.037). Despite the integrity of BR pathways, ASR and LLR show distinctive abnormalities in ET-PD. In our opinion, our electrophysiological findings support the hypothesis that ET-PD is a distinct entity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

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

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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.

Stuttering adults' lack of pre-speech auditory modulation normalizes when speaking with delayed auditory feedback.

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Daliri, Ayoub; Max, Ludo

2018-02-01

Auditory modulation during speech movement planning is limited in adults who stutter (AWS), but the functional relevance of the phenomenon itself remains unknown. We investigated for AWS and adults who do not stutter (AWNS) (a) a potential relationship between pre-speech auditory modulation and auditory feedback contributions to speech motor learning and (b) the effect on pre-speech auditory modulation of real-time versus delayed auditory feedback. Experiment I used a sensorimotor adaptation paradigm to estimate auditory-motor speech learning. Using acoustic speech recordings, we quantified subjects' formant frequency adjustments across trials when continually exposed to formant-shifted auditory feedback. In Experiment II, we used electroencephalography to determine the same subjects' extent of pre-speech auditory modulation (reductions in auditory evoked potential N1 amplitude) when probe tones were delivered prior to speaking versus not speaking. To manipulate subjects' ability to monitor real-time feedback, we included speaking conditions with non-altered auditory feedback (NAF) and delayed auditory feedback (DAF). Experiment I showed that auditory-motor learning was limited for AWS versus AWNS, and the extent of learning was negatively correlated with stuttering frequency. Experiment II yielded several key findings: (a) our prior finding of limited pre-speech auditory modulation in AWS was replicated; (b) DAF caused a decrease in auditory modulation for most AWNS but an increase for most AWS; and (c) for AWS, the amount of auditory modulation when speaking with DAF was positively correlated with stuttering frequency. Lastly, AWNS showed no correlation between pre-speech auditory modulation (Experiment II) and extent of auditory-motor learning (Experiment I) whereas AWS showed a negative correlation between these measures. Thus, findings suggest that AWS show deficits in both pre-speech auditory modulation and auditory-motor learning; however, limited pre

Eletrococleografia extratimpânica na neuropatia/dessincronia auditiva Extratympanic electrocochleography in the diagnosis of auditory neuropathy/auditory dyssynchrony

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Adriana Ribeiro Tavares Anastasio

2008-02-01

Full Text Available O potencial evocado auditivo de tronco encefálico (PEATE vem sendo amplamente utilizado como método para avaliação da função coclear em indivíduos com diagnóstico de neuropatia/dessincronia auditiva (NA/DA. Na ausência das emissões otoacústicas, muitos casos de NA/DA foram diagnosticados pela presença do microfonismo coclear (MC identificado no PEATE. OBJETIVO: Demonstrar a aplicabilidade clínica da eletrococleografia extratimpânica (Ecog-ET no diagnóstico diferencial da NA/DA quando comparada ao PEATE. MATERIAL E MÉTODO: Uma criança com 4 anos de idade, com diagnóstico de NA/DA atendida no Centro de Pesquisas Audiológicas realizou a Ecog-ET com tone burst de 2000Hz nas polaridades de rarefação e condensação. RESULTADOS: Ilustrou-se o registro da Ecog-ET. Com a utilização de protocolo apropriado, o MC pode ser evidenciado e confirmado na Ecog, com qualidade de registro superior ao obtido no PEATE. CONCLUSÃO: A Ecog-ET permitiu uma análise mais detalhada do MC quando comparada ao PEATE tendo, portanto aplicabilidade clínica na investigação da função coclear na NA/DA.The brainstem auditory evoked potential (BAEP is being extensively used as a method for the evaluation of cochlear function in individuals with diagnosis of auditory neuropathy/auditory dyssynchrony (AN/AD. In the absence of otoacoustic emissions, many cases of AN/AD have been diagnosed by the presence of CM identified in the BAEP. AIM: to demonstrate the clinical applicability of extratympanic electrocochleography (ET-Ecochg in the differential diagnosis of AN/AD compared to the BAEP. METHOD: a 4-year-old child with a diagnosis of AN/AD seen at the Audiological Research Center was submitted to ET-Ecochg with a 2000 Hz tone burst in rarefaction and condensation polarities. RESULTS: the ET-Ecochg exam was illustrated. Using an appropriate protocol, it was possible to demonstrate CM and to confirm it in the Ecochg, with a recording quality superior to

The European Union’s normative power in global politics

DEFF Research Database (Denmark)

Manners, Ian

2012-01-01

comparison. Both political and scholarly assessments argue that ‘we are one of the most important, if not the most important, normative powers in the world’ (Barroso in Peterson, 2008: 69) and that ‘Europe has tremendous normative power’ (Moravcsik, 2010: 18). The normative power approach set out here makes...... it possible to explain, understand, and judge the EU in global politics by rethinking the nature of power and actorness in a globalising, multilateralising and multipolarising era. The EU uses normative power in global politics but the question is whether it is more prone than other actors to do so? In areas...... which are core to the ‘European project’, it seems clear that the EU is more disposed to use normative power....

Effect of delayed auditory feedback on stuttering with and without central auditory processing disorders.

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Picoloto, Luana Altran; Cardoso, Ana Cláudia Vieira; Cerqueira, Amanda Venuti; Oliveira, Cristiane Moço Canhetti de

2017-12-07

To verify the effect of delayed auditory feedback on speech fluency of individuals who stutter with and without central auditory processing disorders. The participants were twenty individuals with stuttering from 7 to 17 years old and were divided into two groups: Stuttering Group with Auditory Processing Disorders (SGAPD): 10 individuals with central auditory processing disorders, and Stuttering Group (SG): 10 individuals without central auditory processing disorders. Procedures were: fluency assessment with non-altered auditory feedback (NAF) and delayed auditory feedback (DAF), assessment of the stuttering severity and central auditory processing (CAP). Phono Tools software was used to cause a delay of 100 milliseconds in the auditory feedback. The "Wilcoxon Signal Post" test was used in the intragroup analysis and "Mann-Whitney" test in the intergroup analysis. The DAF caused a statistically significant reduction in SG: in the frequency score of stuttering-like disfluencies in the analysis of the Stuttering Severity Instrument, in the amount of blocks and repetitions of monosyllabic words, and in the frequency of stuttering-like disfluencies of duration. Delayed auditory feedback did not cause statistically significant effects on SGAPD fluency, individuals with stuttering with auditory processing disorders. The effect of delayed auditory feedback in speech fluency of individuals who stutter was different in individuals of both groups, because there was an improvement in fluency only in individuals without auditory processing disorder.

Auditory, visual and auditory-visual memory and sequencing performance in typically developing children.

Science.gov (United States)

Pillai, Roshni; Yathiraj, Asha

2017-09-01

The study evaluated whether there exists a difference/relation in the way four different memory skills (memory score, sequencing score, memory span, & sequencing span) are processed through the auditory modality, visual modality and combined modalities. Four memory skills were evaluated on 30 typically developing children aged 7 years and 8 years across three modality conditions (auditory, visual, & auditory-visual). Analogous auditory and visual stimuli were presented to evaluate the three modality conditions across the two age groups. The children obtained significantly higher memory scores through the auditory modality compared to the visual modality. Likewise, their memory scores were significantly higher through the auditory-visual modality condition than through the visual modality. However, no effect of modality was observed on the sequencing scores as well as for the memory and the sequencing span. A good agreement was seen between the different modality conditions that were studied (auditory, visual, & auditory-visual) for the different memory skills measures (memory scores, sequencing scores, memory span, & sequencing span). A relatively lower agreement was noted only between the auditory and visual modalities as well as between the visual and auditory-visual modality conditions for the memory scores, measured using Bland-Altman plots. The study highlights the efficacy of using analogous stimuli to assess the auditory, visual as well as combined modalities. The study supports the view that the performance of children on different memory skills was better through the auditory modality compared to the visual modality. Copyright © 2017 Elsevier B.V. All rights reserved.

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

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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

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

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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.

Brainstem Tuberculoma in Pregnancy

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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.

Cell-based neurotrophin treatment supports long-term auditory neuron survival in the deaf guinea pig.

Science.gov (United States)

Gillespie, Lisa N; Zanin, Mark P; Shepherd, Robert K

2015-01-28

The cochlear implant provides auditory cues to profoundly deaf patients by electrically stimulating the primary auditory neurons (ANs) of the cochlea. However, ANs degenerate in deafness; the preservation of a robust AN target population, in combination with advances in cochlear implant technology, may provide improved hearing outcomes for cochlear implant patients. The exogenous delivery of neurotrophins such as brain-derived neurotrophic factor (BDNF) and neurotrophin-3 is well known to support AN survival in deafness, and cell-based therapies provide a potential clinically viable option for delivering neurotrophins into the deaf cochlea. This study utilized cells that were genetically modified to express BDNF and encapsulated in alginate microspheres, and investigated AN survival in the deaf guinea pig following (a) cell-based neurotrophin treatment in conjunction with chronic electrical stimulation from a cochlear implant, and (b) long-term cell-based neurotrophin delivery. In comparison to deafened controls, there was significantly greater AN survival following the cell-based neurotrophin treatment, and there were ongoing survival effects for at least six months. In addition, functional benefits were observed following cell-based neurotrophin treatment and chronic electrical stimulation, with a statistically significant decrease in electrically evoked auditory brainstem response thresholds observed during the experimental period. This study demonstrates that cell-based therapies, in conjunction with a cochlear implant, shows potential as a clinically transferable means of providing neurotrophin treatment to support AN survival in deafness. This technology also has the potential to deliver other therapeutic agents, and to be used in conjunction with other biomedical devices for the treatment of a variety of neurodegenerative conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

P50 Suppression in Children with Selective Mutism: A Preliminary Report

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Henkin, Yael; Feinholz, Maya; Arie, Miri; Bar-Haim, Yair

2010-01-01

Evidence suggests that children with selective mutism (SM) display significant aberrations in auditory efferent activity at the brainstem level that may underlie inefficient auditory processing during vocalization, and lead to speech avoidance. The objective of the present study was to explore auditory filtering processes at the cortical level in…

Normative and descriptive rationality: from nature to artifice and back

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Besold, T. R.; Uckelman, S. L.

2018-03-01

Rationality plays a key role in both the study of human reasoning and Artificial Intelligence (AI). Certain notions of rationality have been adopted in AI as guides for the development of intelligent machines and these notions have been given a normative function. The notions of rationality in AI are often taken to be closely related to conceptions of rationality in human contexts. In this paper, we argue that the normative role of rationality differs in the human and artificial contexts. While rationality in human-focused fields of study is normative, prescribing how humans ought to reason, the normative conception in AI is built on a notion of human rationality which is descriptive, not normative, in the human context, as AI aims at building agents which reason as humans do. In order to make this point, we review prominent notions of rationality used in psychology, cognitive science, and (the history of) philosophy, as well as in AI, and discuss some factors that contributed to rationality being assigned the differing normative statuses in the differing fields of study. We argue that while 'rationality' is a normative notion in both AI and in human reasoning, the normativity of the AI conception of 'rationality' is grounded in a descriptive account of human rationality.

Evaluation of afferent pain pathways in adrenomyeloneuropathic patients.

Science.gov (United States)

Yagüe, Sara; Veciana, Misericordia; Casasnovas, Carlos; Ruiz, Montserrat; Pedro, Jordi; Valls-Solé, Josep; Pujol, Aurora

2018-03-01

Patients with adrenomyeloneuropathy may have dysfunctions of visual, auditory, motor and somatosensory pathways. We thought on examining the nociceptive pathways by means of laser evoked potentials (LEPs), to obtain additional information on the pathophysiology of this condition. In 13 adrenomyeloneuropathic patients we examined LEPs to leg, arm and face stimulation. Normative data were obtained from 10 healthy subjects examined in the same experimental conditions. We also examined brainstem auditory evoked potentials (BAEPs), pattern reversal full-field visual evoked potentials (VEPs), motor evoked potentials (MEPs) and somatosensory evoked potentials (SEPs). Upper and lower limb MEPs and SEPs, as well as BAEPs, were abnormal in all patients, while VEPs were abnormal in 3 of them (23.1%). LEPs revealed abnormalities to stimulation of the face in 4 patients (30.7%), the forearm in 4 patients (30.7%) and the leg in 10 patients (76.9%). The pathologic process of adrenomyeloneuropathy is characterized by a preferential involvement of auditory, motor and somatosensory tracts and less severely of the visual and nociceptive pathways. This non-inflammatory distal axonopathy preferably damages large myelinated spinal tracts but there is also partial involvement of small myelinated fibres. LEPs studies can provide relevant information about afferent pain pathways involvement in adrenomyeloneuropathic patients. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Evolutionary Debunking of Normative Realism. Not a Real Threat for Realists

OpenAIRE

Pellegrino, Gianfranco

2017-01-01

A debunking argument has been recently levelled against normative realism. According to this line of reasoning, most of our normative beliefs have been strongly influenced by evolutionary forces. As evolution is a non-truth-tracking process, this influence may lead our normative beliefs off track. If so, normative realists need to provide an explanation of how it is possible that our normative beliefs track stance-independent truth, or of how their falsity could be spotted, when evolution pow...

Auditory Spatial Layout

Science.gov (United States)

Wightman, Frederic L.; Jenison, Rick

1995-01-01

All auditory sensory information is packaged in a pair of acoustical pressure waveforms, one at each ear. While there is obvious structure in these waveforms, that structure (temporal and spectral patterns) bears no simple relationship to the structure of the environmental objects that produced them. The properties of auditory objects and their layout in space must be derived completely from higher level processing of the peripheral input. This chapter begins with a discussion of the peculiarities of acoustical stimuli and how they are received by the human auditory system. A distinction is made between the ambient sound field and the effective stimulus to differentiate the perceptual distinctions among various simple classes of sound sources (ambient field) from the known perceptual consequences of the linear transformations of the sound wave from source to receiver (effective stimulus). Next, the definition of an auditory object is dealt with, specifically the question of how the various components of a sound stream become segregated into distinct auditory objects. The remainder of the chapter focuses on issues related to the spatial layout of auditory objects, both stationary and moving.

Multichannel auditory search: toward understanding control processes in polychotic auditory listening.

Science.gov (United States)

Lee, M D

2001-01-01

Two experiments are presented that serve as a framework for exploring auditory information processing. The framework is referred to as polychotic listening or auditory search, and it requires a listener to scan multiple simultaneous auditory streams for the appearance of a target word (the name of a letter such as A or M). Participants' ability to scan between two and six simultaneous auditory streams of letter and digit names for the name of a target letter was examined using six loudspeakers. The main independent variable was auditory load, or the number of active audio streams on a given trial. The primary dependent variables were target localization accuracy and reaction time. Results showed that as load increased, performance decreased. The performance decrease was evident in reaction time, accuracy, and sensitivity measures. The second study required participants to practice the same task for 10 sessions, for a total of 1800 trials. Results indicated that even with extensive practice, performance was still affected by auditory load. The present results are compared with findings in the visual search literature. The implications for the use of multiple auditory displays are discussed. Potential applications include cockpit and automobile warning displays, virtual reality systems, and training systems.

Designing normative open virtual enterprises

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Garcia, Emilia; Giret, Adriana; Botti, Vicente

2016-03-01

There is an increasing interest on developing virtual enterprises in order to deal with the globalisation of the economy, the rapid growth of information technologies and the increase of competitiveness. In this paper we deal with the development of normative open virtual enterprises (NOVEs). They are systems with a global objective that are composed of a set of heterogeneous entities and enterprises that exchange services following a specific normative context. In order to analyse and design systems of this kind the multi-agent paradigm seems suitable because it offers a specific solution for supporting the social and contractual relationships between enterprises and for formalising their business processes. This paper presents how the Regulated Open Multi-agent systems (ROMAS) methodology, an agent-oriented software methodology, can be used to analyse and design NOVEs. ROMAS offers a complete development process that allows identifying and formalising of the structure of NOVEs, their normative context and the interactions among their members. The use of ROMAS is exemplified by means of a case study that represents an automotive supply chain.

Enterovirus 71 Brainstem Encephalitis and Cognitive and Motor Deficits

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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.

Normative and Descriptive Aspects of Management Education: Differentiation and Integration

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Meirovich, Gavriel

2015-01-01

This study advocates strongly for clear differentiation and synthesis of descriptive and normative approaches in management education. There is a certain isolation of normative and descriptive theoretical frameworks presented in management courses. Normative frameworks in management explain how organizations "should be" managed, while…

Diminished auditory sensory gating during active auditory verbal hallucinations.

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Thoma, Robert J; Meier, Andrew; Houck, Jon; Clark, Vincent P; Lewine, Jeffrey D; Turner, Jessica; Calhoun, Vince; Stephen, Julia

2017-10-01

Auditory sensory gating, assessed in a paired-click paradigm, indicates the extent to which incoming stimuli are filtered, or "gated", in auditory cortex. Gating is typically computed as the ratio of the peak amplitude of the event related potential (ERP) to a second click (S2) divided by the peak amplitude of the ERP to a first click (S1). Higher gating ratios are purportedly indicative of incomplete suppression of S2 and considered to represent sensory processing dysfunction. In schizophrenia, hallucination severity is positively correlated with gating ratios, and it was hypothesized that a failure of sensory control processes early in auditory sensation (gating) may represent a larger system failure within the auditory data stream; resulting in auditory verbal hallucinations (AVH). EEG data were collected while patients (N=12) with treatment-resistant AVH pressed a button to indicate the beginning (AVH-on) and end (AVH-off) of each AVH during a paired click protocol. For each participant, separate gating ratios were computed for the P50, N100, and P200 components for each of the AVH-off and AVH-on states. AVH trait severity was assessed using the Psychotic Symptoms Rating Scales AVH Total score (PSYRATS). The results of a mixed model ANOVA revealed an overall effect for AVH state, such that gating ratios were significantly higher during the AVH-on state than during AVH-off for all three components. PSYRATS score was significantly and negatively correlated with N100 gating ratio only in the AVH-off state. These findings link onset of AVH with a failure of an empirically-defined auditory inhibition system, auditory sensory gating, and pave the way for a sensory gating model of AVH. Copyright © 2017 Elsevier B.V. All rights reserved.

Disaggregated regulation in network sections: The normative and positive theory; Disaggregierte Regulierung in Netzsektoren: Normative und positive Theorie

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Knieps, G. [Inst. fuer Verkehrswissenschaft und Regionalpolitik, Albert-Ludwigs-Univ. Freiburg i.B. (Germany)

2007-09-15

The article deals with the interaction of normative and positive theorie of regulation. Those parts of the network which need regulation could be localised and regulated with the help of the normative theory of the monopolistic bottlenecks. Using the positive theory, the basic elements of a mandate for regulation in the sense of the disaggregated economy of regulation are derived.

Effectiveness of auditory and tactile crossmodal cues in a dual-task visual and auditory scenario.

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Hopkins, Kevin; Kass, Steven J; Blalock, Lisa Durrance; Brill, J Christopher

2017-05-01

In this study, we examined how spatially informative auditory and tactile cues affected participants' performance on a visual search task while they simultaneously performed a secondary auditory task. Visual search task performance was assessed via reaction time and accuracy. Tactile and auditory cues provided the approximate location of the visual target within the search display. The inclusion of tactile and auditory cues improved performance in comparison to the no-cue baseline conditions. In comparison to the no-cue conditions, both tactile and auditory cues resulted in faster response times in the visual search only (single task) and visual-auditory (dual-task) conditions. However, the effectiveness of auditory and tactile cueing for visual task accuracy was shown to be dependent on task-type condition. Crossmodal cueing remains a viable strategy for improving task performance without increasing attentional load within a singular sensory modality. Practitioner Summary: Crossmodal cueing with dual-task performance has not been widely explored, yet has practical applications. We examined the effects of auditory and tactile crossmodal cues on visual search performance, with and without a secondary auditory task. Tactile cues aided visual search accuracy when also engaged in a secondary auditory task, whereas auditory cues did not.

On the Normative Function of Metatheoretical Endeavors

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Zachary Stein

2010-07-01

Full Text Available I reconstruct an historical understanding of metatheory that emphasizes its normative function. The pioneering work of James Mark Baldwin inspires an account of how metatheoretical constructs emerge developmentally and come to serve a discourse-regulative function—overseeing, organizing, and regulating whole fields of discourse. Then I look to Charles S. Peirce as an exemplary normatively oriented metatheorist and explain how both continue a philosophical tradition concerned with the normative function of humanity more broadly. Thus, while I think it is valuable to pursue a variety of metatheoretical endeavors, including descriptive and empirical ones—mapping the terrain of various discourses, or summarizing their contributions—I argue for a specific vision of metatheory as a normative endeavor with rich intellectual and historical precedence. Unpacking some of the implications involved with this way of viewing and doing metatheory lead to considerations about the differences between two general types of metatheory (scholastic-reductionist and cosmopolitan-comprehensivist, the role of philosophical interlocutors in the public-sphere, and the trajectory of human evolution in the coming decades.

Normative ethics does not need a foundation: it needs more science.

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Quintelier, Katinka; Van Speybroeck, Linda; Braeckman, Johan

2011-03-01

The impact of science on ethics forms since long the subject of intense debate. Although there is a growing consensus that science can describe morality and explain its evolutionary origins, there is less consensus about the ability of science to provide input to the normative domain of ethics. Whereas defenders of a scientific normative ethics appeal to naturalism, its critics either see the naturalistic fallacy committed or argue that the relevance of science to normative ethics remains undemonstrated. In this paper, we argue that current scientific normative ethicists commit no fallacy, that criticisms of scientific ethics contradict each other, and that scientific insights are relevant to normative inquiries by informing ethics about the options open to the ethical debate. Moreover, when conceiving normative ethics as being a nonfoundational ethics, science can be used to evaluate every possible norm. This stands in contrast to foundational ethics in which some norms remain beyond scientific inquiry. Finally, we state that a difference in conception of normative ethics underlies the disagreement between proponents and opponents of a scientific ethics. Our argument is based on and preceded by a reconsideration of the notions naturalistic fallacy and foundational ethics. This argument differs from previous work in scientific ethics: whereas before the philosophical project of naturalizing the normative has been stressed, here we focus on concrete consequences of biological findings for normative decisions or on the day-to-day normative relevance of these scientific insights.

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.)

Attending to auditory memory.

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Zimmermann, Jacqueline F; Moscovitch, Morris; Alain, Claude

2016-06-01

Attention to memory describes the process of attending to memory traces when the object is no longer present. It has been studied primarily for representations of visual stimuli with only few studies examining attention to sound object representations in short-term memory. Here, we review the interplay of attention and auditory memory with an emphasis on 1) attending to auditory memory in the absence of related external stimuli (i.e., reflective attention) and 2) effects of existing memory on guiding attention. Attention to auditory memory is discussed in the context of change deafness, and we argue that failures to detect changes in our auditory environments are most likely the result of a faulty comparison system of incoming and stored information. Also, objects are the primary building blocks of auditory attention, but attention can also be directed to individual features (e.g., pitch). We review short-term and long-term memory guided modulation of attention based on characteristic features, location, and/or semantic properties of auditory objects, and propose that auditory attention to memory pathways emerge after sensory memory. A neural model for auditory attention to memory is developed, which comprises two separate pathways in the parietal cortex, one involved in attention to higher-order features and the other involved in attention to sensory information. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.

Astrocyte Hypertrophy and Microglia Activation in the Rat Auditory Midbrain Is Induced by Electrical Intracochlear Stimulation.

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Rosskothen-Kuhl, Nicole; Hildebrandt, Heika; Birkenhäger, Ralf; Illing, Robert-Benjamin

2018-01-01

Neuron-glia interactions contribute to tissue homeostasis and functional plasticity in the mammalian brain, but it remains unclear how this is achieved. The potential of central auditory brain tissue for stimulation-dependent cellular remodeling was studied in hearing-experienced and neonatally deafened rats. At adulthood, both groups received an intracochlear electrode into the left cochlea and were continuously stimulated for 1 or 7 days after waking up from anesthesia. Normal hearing and deafness were assessed by auditory brainstem responses (ABRs). The effectiveness of stimulation was verified by electrically evoked ABRs as well as immunocytochemistry and in situ hybridization for the immediate early gene product Fos on sections through the auditory midbrain containing the inferior colliculus (IC). Whereas hearing-experienced animals showed a tonotopically restricted Fos response in the IC contralateral to electrical intracochlear stimulation, Fos-positive neurons were found almost throughout the contralateral IC in deaf animals. In deaf rats, the Fos response was accompanied by a massive increase of GFAP indicating astrocytic hypertrophy, and a local activation of microglial cells identified by IBA1. These glia responses led to a noticeable increase of neuron-glia approximations. Moreover, staining for the GABA synthetizing enzymes GAD65 and GAD67 rose significantly in neuronal cell bodies and presynaptic boutons in the contralateral IC of deaf rats. Activation of neurons and glial cells and tissue re-composition were in no case accompanied by cell death as would have been apparent by a Tunel reaction. These findings suggest that growth and activity of glial cells is crucial for the local adjustment of neuronal inhibition to neuronal excitation.

A Study of the Central Auditory Function in Stutters by Masking Level Difference and Synthetic Sentence Identification Tests

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Afsaneh Rajab

2007-06-01

Full Text Available Background and Aim: There are evidences that indicate a relationship between auditory processing disor¬ders and stuttering,¬ and any disorder in the central auditory function can be at least one of the underly¬ing causes of stuttering. Even though, using the most state of the art radiographic technologies, i.e. MRI, no definitive answer has been given in relative to this question. In this research, using Mask-ing Level Difference (MLD and Synthetic Sentence Identification (SSI tests, the central auditory func¬tion of stutters and normal group was evaluated.Materials and Methods: In this study was analytic cross-sectional, fifteen male patients with stutter-ing and 15 male normal cases with the age range from 16 to 40 years (average age 26.78 year were evalu¬ated. SSI-ICM, SSI-CCM and MLD tests were performed. The results were compared in both groups.Results: Although stutterers mean MLD was less than that of normal group, the different was not signifi¬cant between stutters and normal group in SSI test in right ear at negative MCRs. There was a signifi¬cant difference in ICM state, but in CCM state, there was no significant difference between the aver¬age score of two groups in various MCRs.Conclusion: The findings of this research is compatible with those of similar researches about the SSI test and the pattern of results, probably indicates a partial dysfunction of brainstem in some of the stutters.

Mechanical Characterization of Immature Porcine Brainstem in Tension at Dynamic Strain Rates.

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Zhao, Hui; Yin, Zhiyong; Li, Kui; Liao, Zhikang; Xiang, Hongyi; Zhu, Feng

2016-01-21

Many brain injury cases involve pediatric road traffic accidents, and among these, brainstem injury causes disastrous outcomes. A thorough understanding of the tensile characterization of immature brainstem tissue is crucial in modeling traumatic brain injury sustained by children, but limited experimental data in tension is available for the immature brain tissue at dynamic strain rates. We harvested brainstem tissue from immature pigs (about 4 weeks old, and at a developmental stage similar to that of human toddlers) as a byproduct from a local slaughter house and very carefully prepared the samples. Tensile tests were performed on specimens at dynamic strain rates of 2/s, 20/s, and 100/s using a biological material instrument. The constitutive models, Fung, Ogden, Gent, and exponential function, for immature brainstem tissue material property were developed for the recorded experimental data using OriginPro 8.0 software. The t test was performed for infinitesimal shear modules. The curves of stress-versus-stretch ratio were convex in shape, and inflection points were found in all the test groups at the strain of about 2.5%. The average Lagrange stress of the immature brainstem specimen at the 30% strain at the strain rates of 2, 20, and 100/s was 273±114, 515±107, and 1121±197 Pa, respectively. The adjusted R-Square (R2) of Fung, Ogden, Gent, and exponential model was 0.820≤R2≤0.933, 0.774≤R2≤0.940, 0.650≤R2≤0.922, and 0.852≤R2≤0.981, respectively. The infinitesimal shear modulus of the strain energy functions showed a significant association with the strain rate (pmaterial in dynamic tensile tests, and the tissue becomes stiffer with increased strain rate. The reported results may be useful in the study of brain injuries in children who sustain injuries in road traffic accidents. Further research in more detail should be performed in the future.

Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

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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 segmentation and corrective 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

Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

International Nuclear Information System (INIS)

Tu, Yi-Fang; Chen, Cheng-Yu; Lin, Yuh-Jey; Chang, Ying-Chao; Huang, Chao-Ching

2005-01-01

Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic-ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation. (orig.)

Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

Energy Technology Data Exchange (ETDEWEB)

Tu, Yi-Fang [National Cheng Kung University Hospital, Department of Emergency Medicine, Tainan (Taiwan); Chen, Cheng-Yu [National Defense Medical Center, Department of Radiology, Taipei (Taiwan); Lin, Yuh-Jey [National Cheng Kung University Hospital, Department of Pediatrics, Tainan (Taiwan); Chang, Ying-Chao [Kaohsiung Chang Gung Children Hospital, Department of Pediatrics, Kaohsiung (Taiwan); Huang, Chao-Ching [National Cheng Kung University Hospital, Department of Pediatrics, Tainan (Taiwan); National Cheng Kung University Hospital, Department of Institute of Molecular Medicine, Tainan (Taiwan)

2005-09-01

Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic-ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation. (orig.)

Predictive coding of visual-auditory and motor-auditory events: An electrophysiological study.

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Stekelenburg, Jeroen J; Vroomen, Jean

2015-11-11

The amplitude of auditory components of the event-related potential (ERP) is attenuated when sounds are self-generated compared to externally generated sounds. This effect has been ascribed to internal forward modals predicting the sensory consequences of one's own motor actions. Auditory potentials are also attenuated when a sound is accompanied by a video of anticipatory visual motion that reliably predicts the sound. Here, we investigated whether the neural underpinnings of prediction of upcoming auditory stimuli are similar for motor-auditory (MA) and visual-auditory (VA) events using a stimulus omission paradigm. In the MA condition, a finger tap triggered the sound of a handclap whereas in the VA condition the same sound was accompanied by a video showing the handclap. In both conditions, the auditory stimulus was omitted in either 50% or 12% of the trials. These auditory omissions induced early and mid-latency ERP components (oN1 and oN2, presumably reflecting prediction and prediction error), and subsequent higher-order error evaluation processes. The oN1 and oN2 of MA and VA were alike in amplitude, topography, and neural sources despite that the origin of the prediction stems from different brain areas (motor versus visual cortex). This suggests that MA and VA predictions activate a sensory template of the sound in auditory cortex. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2015 Elsevier B.V. All rights reserved.

Sex Differences in Neurophysiological Activation Patterns During Phonological Input Processing: An Influencing Factor for Normative Data.

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Aerts, Annelies; van Mierlo, Pieter; Hartsuiker, Robert J; Santens, Patrick; De Letter, Miet

2015-11-01

In the context of neurophysiological normative data, it has been established that aging has a significant impact on neurophysiological correlates of auditory phonological input processes, such as phoneme discrimination (PD) and word recognition (WR). Besides age, sex is another demographic factor that influences several language processes. We aimed to disentangle whether sex has a similar effect on PD and WR. Event-related potentials (ERPs) were recorded in 20 men and 24 women. During PD, three phonemic contrasts (place and manner of articulation and voicing) were compared using the attentive P300 and pre-attentive Mismatch Negativity. To investigate WR, real words were contrasted with pseudowords in a pre-attentive oddball task. Women demonstrated a larger sensitivity to spectrotemporal differences, as evidenced by larger P300 responses to the place of articulation (PoA) contrast and larger P300 and MMN responses than men in PoA-based PD. Men did not display such sensitivity. Attention played an important role, considering that women needed more attentional resources to differentiate between PoA and the other phonemic contrasts. During WR, pseudowords evoked larger amplitudes already 100 ms post-stimulus independent of sex. However, women had decreased P200 latencies, but longer N400 latencies in response to pseudowords, whereas men showed increased N400 latencies compared to women in response to real words. The current results demonstrate significant sex-related influences on phonological input processes. Therefore, existing neurophysiological normative data for age should be complemented for the factor sex.

Brainstem pathology in spasmodic dysphonia

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Simonyan, Kristina; Ludlow, Christy L.; Vortmeyer, Alexander O.

2009-01-01

Spasmodic dysphonia (SD) is a primary focal dystonia of unknown pathophysiology, characterized by involuntary spasms in the laryngeal muscles during speech production. We examined two rare cases of postmortem brainstem tissue from SD patients compared to four controls. In SD patients, small clusters of inflammation were found in the reticular formation surrounding solitary tract, spinal trigeminal and ambigual nuclei, inferior olive and pyramids. Mild neuronal degeneration and depigmentation were observed in the substantia nigra and locus coeruleus. No abnormal protein accumulations and no demyelination or axonal degeneration were found. These neuropathological findings may provide insights into the pathophysiology of SD. PMID:19795469

Normative beliefs and sexual risk in China.

Science.gov (United States)

Li, Li; Ding, Ying Ying; Wu, Zunyou; Rotheram-Borus, Mary Jane; Guo, Sam

2011-08-01

We examined normative beliefs about multiple sexual partners and social status in China and their association with risky sexual behaviors and sexually transmitted infections (STIs). Self-reported and biological markers of sexual risk were examined among 3,716 market vendors from a city in eastern China. Men who were older or with less education believed having multiple sexual partners was linked to higher social status. Adjusting for demographic characteristics, normative beliefs were significantly associated with having multiple sexual partners, while having multiple sexual partners was significantly associated with STIs. Normative beliefs regarding sexual behaviors may play an important role in individual risk behaviors. Future HIV/STI interventions must address community beliefs about the positive meaning of sexual risks, particularly among men with traditional beliefs about gender roles.

Development of the auditory system

Science.gov (United States)

Litovsky, Ruth

2015-01-01

Auditory development involves changes in the peripheral and central nervous system along the auditory pathways, and these occur naturally, and in response to stimulation. Human development occurs along a trajectory that can last decades, and is studied using behavioral psychophysics, as well as physiologic measurements with neural imaging. The auditory system constructs a perceptual space that takes information from objects and groups, segregates sounds, and provides meaning and access to communication tools such as language. Auditory signals are processed in a series of analysis stages, from peripheral to central. Coding of information has been studied for features of sound, including frequency, intensity, loudness, and location, in quiet and in the presence of maskers. In the latter case, the ability of the auditory system to perform an analysis of the scene becomes highly relevant. While some basic abilities are well developed at birth, there is a clear prolonged maturation of auditory development well into the teenage years. Maturation involves auditory pathways. However, non-auditory changes (attention, memory, cognition) play an important role in auditory development. The ability of the auditory system to adapt in response to novel stimuli is a key feature of development throughout the nervous system, known as neural plasticity. PMID:25726262

Animal models for auditory streaming

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Itatani, Naoya

2017-01-01

Sounds in the natural environment need to be assigned to acoustic sources to evaluate complex auditory scenes. Separating sources will affect the analysis of auditory features of sounds. As the benefits of assigning sounds to specific sources accrue to all species communicating acoustically, the ability for auditory scene analysis is widespread among different animals. Animal studies allow for a deeper insight into the neuronal mechanisms underlying auditory scene analysis. Here, we will review the paradigms applied in the study of auditory scene analysis and streaming of sequential sounds in animal models. We will compare the psychophysical results from the animal studies to the evidence obtained in human psychophysics of auditory streaming, i.e. in a task commonly used for measuring the capability for auditory scene analysis. Furthermore, the neuronal correlates of auditory streaming will be reviewed in different animal models and the observations of the neurons’ response measures will be related to perception. The across-species comparison will reveal whether similar demands in the analysis of acoustic scenes have resulted in similar perceptual and neuronal processing mechanisms in the wide range of species being capable of auditory scene analysis. This article is part of the themed issue ‘Auditory and visual scene analysis’. PMID:28044022

Focus Groups as Social Arenas for the Negotiation of Normativity

DEFF Research Database (Denmark)

Kristiansen, T. M.; Gronkjaer, M.

2018-01-01

Aim: This article aims to demonstrate how focus group discussions act as a social arena for the negotiation of social norms and normativity and to discuss the implications for the analysis of focus group discussions. Participants and methods: We have used sequences of group interactions from...... a focus group study on everyday life and chronic illness to demonstrate how methodological tools from conversation analysis and discursive psychology can be used to facilitate a systematic analysis of the negotiation and legitimization of social norms and normativity in focus groups. The empirical data...... consisted of six focus groups with a total of 32 participants. Results: The analysis demonstrated negotiations on normativity concerning four central aspects related to living with chronic illness: negotiating normativity about adjustment to the disease, negotiating normativity about being a dutiful...

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...... 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...

Congenital abnormality of the inner ear and internal auditory canal in a patient with deep sensorineural hearing loss: A case report

International Nuclear Information System (INIS)

Rivera, Diego; Saab, Said; Cordoba, Claudia; Montes, Guillermo; Barreto, Tatiana

2010-01-01

CT and MRI are complementary studies that have proven to be the best radiological tools in screening of children with unilateral or bilateral sensorineural hearing loss. Only about a 20% of the patients with congenital sensor neural hearing loss have manifestations in images. Due to the fact that most of these manifestations initiate in the bone, the CT is the first line of image study. MRI is indicated in the evaluation of suspected agenesis, neuropathy, aplasia or hypoplasia of the vestibulocochlear nerve, often associated with this type of hearing loss. We present a case of a 6 year old patient with deep bilateral sensor neural hearing loss, with radiological studies to determine a potential candidate for a cochlear or auditory brainstem implant as hearing rehabilitation.

Identification of clinical target areas in the brainstem of prion‐infected mice

Science.gov (United States)

Mirabile, Ilaria; Jat, Parmjit S.; Brandner, Sebastian

2015-01-01

Aims While prion infection ultimately involves the entire brain, it has long been thought that the abrupt clinical onset and rapid neurological decline in laboratory rodents relates to involvement of specific critical neuroanatomical target areas. The severity and type of clinical signs, together with the rapid progression, suggest the brainstem as a candidate location for such critical areas. In this study we aimed to correlate prion pathology with clinical phenotype in order to identify clinical target areas. Method We conducted a comprehensive survey of brainstem pathology in mice infected with two distinct prion strains, which produce different patterns of pathology, in mice overexpressing prion protein (with accelerated clinical onset) and in mice in which neuronal expression was reduced by gene targeting (which greatly delays clinical onset). Results We identified specific brainstem areas that are affected by prion pathology during the progression of the disease. In the early phase of disease the locus coeruleus, the nucleus of the solitary tract, and the pre‐Bötzinger complex were affected by prion protein deposition. This was followed by involvement of the motor and autonomic centres of the brainstem. Conclusions Neurodegeneration in the locus coeruleus, the nucleus of the solitary tract and the pre‐Bötzinger complex predominated and corresponded to the manifestation of the clinical phenotype. Because of their fundamental role in controlling autonomic function and the overlap with clinical signs in sporadic Creutzfeldt–Jakob disease, we suggest that these nuclei represent key clinical target areas in prion diseases. PMID:25311251

Energy conservation normatives in Italy: Thermotechnical Committee organizational efforts

Energy Technology Data Exchange (ETDEWEB)

Casagrande, A [Comitato Termotecnico Italiano, Milan (Italy)

1991-10-01

A recent Italian law (No. 10/91) calls for energy conservation to be implemented in building materials and HVAC systems through the creation of a suitable set of normatives. The CTI (Italian Thermotechnical Committee) has been assigned the task of creating these normatives and is currently in the organizational stage. This paper lists the proposed normatives and reports on CTI's progress in assembling groups of consultants from various sectors - public administration, end users, industrial firms, etc.

Brainstem evoked response audiometry: an investigatory tool in detecting hepatic encephalopathy in decompensated chronic liver disease.

Science.gov (United States)

Kabali, Balasubramanian; Velayutham, Gowri; Kapali, Suresh Chander

2014-01-01

It is estimated that globally there is a marked increase in liver disease with reports of rising morbidity and mortality, particularly in younger age groups. Brainstem auditory evoked potential (BAEP) was recorded in 60 decompensated chronic liver disease (DCLD) subjects who fulfilled the selection criteria and compared to 60 age and gender matched healthy subjects with normal liver functions. DCLD subjects were divided into two inter groups based on presence or absence of hepatic encephalopathy (HE). Group 1 comprises of 30 subjects of grade- I HE and Group 2 included 30 subjects without hepatic encephalopathy (NHE). Absolute and interpeak wave latencies were measured. Results were analysed by student independent t- test using SPSS software 11 version. Statistical significance was tested using P value. From the present study it can be concluded that the central nervous system is involved in liver cirrhosis evidenced by an abnormal BAEP latencies parameters. This shows that there may be progressive demyelination occurring along with axonal loss or dysfunction in liver cirrhosis HE. This study suggests that periodic evaluation of cirrhotic individuals to such test will help in monitoring the progress of encephalopathy. The prime goal of this study is early diagnosis and initiation of treatment before the onset of coma can reduce the fatality rate.

Social normative beliefs about smoking among Vietnamese adolescents.

Science.gov (United States)

Page, Randy M; Huong, Nguyen Thanh; Chi, Hoang Khanh; Tien, Truong Quang

2012-01-01

Tobacco-related deaths in Vietnam are forecast to climb from 40 000 annually to 70 000 by 2030. Previous research in Western nations has found social factors to be important determinants of adolescent smoking. Because these factors remain unexplored in Vietnamese youth, the purpose of this study was to examine social normative beliefs regarding smoking in a school-based sample of North Vietnamese adolescents and the association of these factors with smoking behavior and susceptibility to smoking. Three measures of normative beliefs regarding smoking were evaluated in cross-sectional surveys of secondary students. Of the 3 measures, parent/peer disapproval was the most consistent normative belief associated with smoking behavior and susceptibility to smoking. Youth smoking prevention programs should consider assessing and taking into account normative beliefs and develop strategies that provide accurate information about the actual prevalence of smoking, the types of individuals who smoke, and approval/disapproval of smoking by parents and peers.

Normative expectations : Employing "communities of practice" models for assessing journalism's normative claims

NARCIS (Netherlands)

Eldridge, Scott; Steel, John

2016-01-01

Journalism's relationship with the public has historically rested on an assumption of its Fourth Estate roles and as fulfilling democratic imperatives. The normative dimensions of these ideals have also long been taken as given in journalism studies, serving as a starting point for discussions of

Improvement of auditory hallucinations and reduction of primary auditory area's activation following TMS

International Nuclear Information System (INIS)

Giesel, Frederik L.; Mehndiratta, Amit; Hempel, Albrecht; Hempel, Eckhard; Kress, Kai R.; Essig, Marco; Schröder, Johannes

2012-01-01

Background: In the present case study, improvement of auditory hallucinations following transcranial magnetic stimulation (TMS) therapy was investigated with respect to activation changes of the auditory cortices. Methods: Using functional magnetic resonance imaging (fMRI), activation of the auditory cortices was assessed prior to and after a 4-week TMS series of the left superior temporal gyrus in a schizophrenic patient with medication-resistant auditory hallucinations. Results: Hallucinations decreased slightly after the third and profoundly after the fourth week of TMS. Activation in the primary auditory area decreased, whereas activation in the operculum and insula remained stable. Conclusions: Combination of TMS and repetitive fMRI is promising to elucidate the physiological changes induced by TMS.

Behavioral determination of stimulus pair discrimination of auditory acoustic and electrical stimuli using a classical conditioning and heart-rate approach.

Science.gov (United States)

Morgan, Simeon J; Paolini, Antonio G

2012-06-06

Acute animal preparations have been used in research prospectively investigating electrode designs and stimulation techniques for integration into neural auditory prostheses, such as auditory brainstem implants and auditory midbrain implants. While acute experiments can give initial insight to the effectiveness of the implant, testing the chronically implanted and awake animals provides the advantage of examining the psychophysical properties of the sensations induced using implanted devices. Several techniques such as reward-based operant conditioning, conditioned avoidance, or classical fear conditioning have been used to provide behavioral confirmation of detection of a relevant stimulus attribute. Selection of a technique involves balancing aspects including time efficiency (often poor in reward-based approaches), the ability to test a plurality of stimulus attributes simultaneously (limited in conditioned avoidance), and measure reliability of repeated stimuli (a potential constraint when physiological measures are employed). Here, a classical fear conditioning behavioral method is presented which may be used to simultaneously test both detection of a stimulus, and discrimination between two stimuli. Heart-rate is used as a measure of fear response, which reduces or eliminates the requirement for time-consuming video coding for freeze behaviour or other such measures (although such measures could be included to provide convergent evidence). Animals were conditioned using these techniques in three 2-hour conditioning sessions, each providing 48 stimulus trials. Subsequent 48-trial testing sessions were then used to test for detection of each stimulus in presented pairs, and test discrimination between the member stimuli of each pair. This behavioral method is presented in the context of its utilisation in auditory prosthetic research. The implantation of electrocardiogram telemetry devices is shown. Subsequent implantation of brain electrodes into the Cochlear

Social normative beliefs regarding cigarette smoking in Hungarian adolescents.

Science.gov (United States)

Page, Randy M; Piko, Bettina F; Balazs, Mate A; Struk, Tamara

2011-10-01

Hungary will continue to experience a high burden of disease and death from lung cancer and other tobacco-induced disease unless there is a significant reduction in youth smoking. Social factors have been found to be among the most important determinants of adolescent smoking, yet few studies have investigated social normative beliefs in Hungarian youth. The purpose of the current study was to investigate three measures of smoking normative beliefs thought to influence adolescent smoking: perceived prevalence of smoking; perceived popularity of smoking among successful/elite elements of society; and perceived disapproval by friends and family. A cross-sectional school-based survey of eighth grade (n = 258) and 12th grade (n = 288) students in Mako, Hungary was conducted to assess social normative beliefs about smoking, current smoking, ever smoking, and susceptibility to smoking. The association of the normative beliefs with the smoking behavior variables was examined through logistic regression analysis, and the underlying factor structure of the normative belief items in the current sample was determined through factor analysis. The percent of boys reporting current smoking was 40.5% in 12th grade and 27.0% in eighth grade. Among girls, the percent was 44.0% of 12th graders and 29.1% of eighth graders. Parent/peer disapproval was the most consistently associated normative belief with smoking behavior and susceptibility to smoking across both samples. Youth smoking prevention programs should consider assessing and taking into account normative beliefs and develop strategies that provide accurate information about the actual prevalence of smoking, the types of individuals who smoke, and approval/disapproval of smoking by parents and peers. © 2011 The Authors. Pediatrics International © 2011 Japan Pediatric Society.

Auditory Perspective Taking

National Research Council Canada - National Science Library

Martinson, Eric; Brock, Derek

2006-01-01

.... From this knowledge of another's auditory perspective, a conversational partner can then adapt his or her auditory output to overcome a variety of environmental challenges and insure that what is said is intelligible...

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.

Competition and convergence between auditory and cross-modal visual inputs to primary auditory cortical areas

Science.gov (United States)

Mao, Yu-Ting; Hua, Tian-Miao

2011-01-01

Sensory neocortex is capable of considerable plasticity after sensory deprivation or damage to input pathways, especially early in development. Although plasticity can often be restorative, sometimes novel, ectopic inputs invade the affected cortical area. Invading inputs from other sensory modalities may compromise the original function or even take over, imposing a new function and preventing recovery. Using ferrets whose retinal axons were rerouted into auditory thalamus at birth, we were able to examine the effect of varying the degree of ectopic, cross-modal input on reorganization of developing auditory cortex. In particular, we assayed whether the invading visual inputs and the existing auditory inputs competed for or shared postsynaptic targets and whether the convergence of input modalities would induce multisensory processing. We demonstrate that although the cross-modal inputs create new visual neurons in auditory cortex, some auditory processing remains. The degree of damage to auditory input to the medial geniculate nucleus was directly related to the proportion of visual neurons in auditory cortex, suggesting that the visual and residual auditory inputs compete for cortical territory. Visual neurons were not segregated from auditory neurons but shared target space even on individual target cells, substantially increasing the proportion of multisensory neurons. Thus spatial convergence of visual and auditory input modalities may be sufficient to expand multisensory representations. Together these findings argue that early, patterned visual activity does not drive segregation of visual and auditory afferents and suggest that auditory function might be compromised by converging visual inputs. These results indicate possible ways in which multisensory cortical areas may form during development and evolution. They also suggest that rehabilitative strategies designed to promote recovery of function after sensory deprivation or damage need to take into

Differential Recruitment of Auditory Cortices in the Consolidation of Recent Auditory Fearful Memories.

Science.gov (United States)

Cambiaghi, Marco; Grosso, Anna; Renna, Annamaria; Sacchetti, Benedetto

2016-08-17

Memories of frightening events require a protracted consolidation process. Sensory cortex, such as the auditory cortex, is involved in the formation of fearful memories with a more complex sensory stimulus pattern. It remains controversial, however, whether the auditory cortex is also required for fearful memories related to simple sensory stimuli. In the present study, we found that, 1 d after training, the temporary inactivation of either the most anterior region of the auditory cortex, including the primary (Te1) cortex, or the most posterior region, which included the secondary (Te2) component, did not affect the retention of recent memories, which is consistent with the current literature. However, at this time point, the inactivation of the entire auditory cortices completely prevented the formation of new memories. Amnesia was site specific and was not due to auditory stimuli perception or processing and strictly related to the interference with memory consolidation processes. Strikingly, at a late time interval 4 d after training, blocking the posterior part (encompassing the Te2) alone impaired memory retention, whereas the inactivation of the anterior part (encompassing the Te1) left memory unaffected. Together, these data show that the auditory cortex is necessary for the consolidation of auditory fearful memories related to simple tones in rats. Moreover, these results suggest that, at early time intervals, memory information is processed in a distributed network composed of both the anterior and the posterior auditory cortical regions, whereas, at late time intervals, memory processing is concentrated in the most posterior part containing the Te2 region. Memories of threatening experiences undergo a prolonged process of "consolidation" to be maintained for a long time. The dynamic of fearful memory consolidation is poorly understood. Here, we show that 1 d after learning, memory is processed in a distributed network composed of both primary Te1 and

Normative Judgments and Individual Essence.

Science.gov (United States)

De Freitas, Julian; Tobia, Kevin P; Newman, George E; Knobe, Joshua

2017-04-01

A growing body of research has examined how people judge the persistence of identity over time-that is, how they decide that a particular individual is the same entity from one time to the next. While a great deal of progress has been made in understanding the types of features that people typically consider when making such judgments, to date, existing work has not explored how these judgments may be shaped by normative considerations. The present studies demonstrate that normative beliefs do appear to play an important role in people's beliefs about persistence. Specifically, people are more likely to judge that the identity of a given entity (e.g., a hypothetical nation) remains the same when its features improve (e.g., the nation becomes more egalitarian) than when its features deteriorate (e.g., the nation becomes more discriminatory). Study 1 provides a basic demonstration of this effect. Study 2 shows that this effect is moderated by individual differences in normative beliefs. Study 3 examines the underlying mechanism, which is the belief that, in general, various entities are essentially good. Study 4 directly manipulates beliefs about essence to show that the positivity bias regarding essences is causally responsible for the effect. Copyright © 2016 Cognitive Science Society, Inc.

7 Tesla 22-channel wrap-around coil array for cervical spinal cord and brainstem imaging.

Science.gov (United States)

Zhang, Bei; Seifert, Alan C; Kim, Joo-Won; Borrello, Joseph; Xu, Junqian

2017-10-01

Increased signal-to-noise ratio and blood oxygenation level-dependent sensitivity at 7 Tesla (T) have the potential to enable high-resolution imaging of the human cervical spinal cord and brainstem. We propose a new two-panel radiofrequency coil design for these regions to fully exploit the advantages of ultra-high field. A two-panel array, containing four transmit/receive and 18 receive-only elements fully encircling the head and neck, was constructed following simulations demonstrating the B1+ and specific absorption rate (SAR) benefits of two-panel over one-panel arrays. This array was compared with a previously reported posterior-only array and tested for safety using a phantom. Its anatomical, functional, and diffusion MRI performance was demonstrated in vivo. The two-panel array produced more uniform B1+ across the brainstem and cervical spinal cord without compromising SAR, and achieved 70% greater receive sensitivity than the posterior-only array. The two-panel design enabled acceleration of R = 2 × 2 in two dimensions or R = 3 in a single dimension. High quality in vivo anatomical, functional, and diffusion images of the human cervical spinal cord and brainstem were acquired. We have designed and constructed a wrap-around coil array with excellent performance for cervical spinal cord and brainstem MRI at 7T, which enables simultaneous human cervical spinal cord and brainstem functional MRI. Magn Reson Med 78:1623-1634, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

THE STUDENTS’ REPRESENTATIONS OF CIVIL SERVANTS’ NORMATIVE ORIENTATION

Directory of Open Access Journals (Sweden)

Alexander A Oboznov

2017-12-01

Full Text Available The concept of the normative personal orientation seeks to specify how personnel motivation should be organized in the value-motivational sphere for professional activity execution in accordance with its social purpose. Based on the priority of the civil service social purpose, the hierarchical structure of the personal normative orientations was theoretically validated. Social motives related to serving for the benefit of the Fatherland as well as work motives associated with the achievement of some role positions are the major motives. The subordinate motives are the monetary rewards and self-development. Development of the future civil servants’ orientation is based on a conscious idea about the required motives’ subordination, that is, about the normative civil servant’s orientation. The study involved 63 students of the 2nd and 4th year studying at the Russian management institute in the specialty “Customs” and 51 students of the 1st and 2nd year studying at the Public Administration Academy of the Republic of Armenia, as well as 4 experts (two from Russia and Armenia having long-term experience in the civil service. The method is an author’s closed-questions’ inventory containing a list of 18 personal goals, that should guide the civil servant in professional work. The instruction required the selection of five most important goals. An absolute majority (from 66 to 90% of Russian and Armenian students has the motives’ subordination that is inconsistent with the normative orientation. According to the students’ view, self-development, self-creation and material benefit are the leading motives of a civil servant. The expert motives’ representations are identical to the required content of civil servant normative orientation. The authors defined the need to develop a special psychological and educational program for promoting required representations about the normative orientation of future civil servants.

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...

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

Manipulation of Auditory Inputs as Rehabilitation Therapy for Maladaptive Auditory Cortical Reorganization

Directory of Open Access Journals (Sweden)

Hidehiko Okamoto

2018-01-01

Full Text Available Neurophysiological and neuroimaging data suggest that the brains of not only children but also adults are reorganized based on sensory inputs and behaviors. Plastic changes in the brain are generally beneficial; however, maladaptive cortical reorganization in the auditory cortex may lead to hearing disorders such as tinnitus and hyperacusis. Recent studies attempted to noninvasively visualize pathological neural activity in the living human brain and reverse maladaptive cortical reorganization by the suitable manipulation of auditory inputs in order to alleviate detrimental auditory symptoms. The effects of the manipulation of auditory inputs on maladaptively reorganized brain were reviewed herein. The findings obtained indicate that rehabilitation therapy based on the manipulation of auditory inputs is an effective and safe approach for hearing disorders. The appropriate manipulation of sensory inputs guided by the visualization of pathological brain activities using recent neuroimaging techniques may contribute to the establishment of new clinical applications for affected individuals.

Measuring Normative Risk Preferences

NARCIS (Netherlands)

G.A.G. Alserda (Gosse)

2017-01-01

textabstractThe results of eliciting risk preferences depend on the elicitation method. Different methods of measuring the same variable tend to produce different results. This raises the question whether normative risk preferences can be elicited at all. Using two types of manipulation, I assess

Informational and Normative Influences in Conformity from a Neurocomputational Perspective.

Science.gov (United States)

Toelch, Ulf; Dolan, Raymond J

2015-10-01

We consider two distinct influences that drive conformity behaviour. Whereas informational influences facilitate adaptive and accurate responses, normative influences bias decisions to enhance social acceptance. We explore these influences from a perspective of perceptual and value-based decision-making models and apply these models to classical works on conformity. We argue that an informational account predicts a surprising tendency to conform. Moreover, we detail how normative influences fit into this framework and interact with social influences. Finally, we explore potential neuronal substrates for informational and normative influences based on a consideration of the neurobiological literature, highlighting conceptual shortcomings particularly with regard to a failure to segregate informational and normative influences. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparação dos estímulos clique e CE-chirp® no registro do Potencial Evocado Auditivo de Tronco Encefálico Comparison of click and CE-chirp® stimuli on Brainstem Auditory Evoked Potential recording

Directory of Open Access Journals (Sweden)

Gabriela Ribeiro Ivo Rodrigues

2012-12-01

Full Text Available OBJETIVO: Comparar as latências e as amplitudes da onda V no registro do Potencial Evocado Auditivo de Tronco Encefálico (PEATE com os estímulos clique e CE-chirp® e a presença ou ausência das ondas I, III e V em fortes intensidades. MÉTODOS: Estudo transversal com 12 adultos com limiares audiométricos PURPOSE: To compare the latencies and amplitudes of wave V on the Brainstem Auditory Evoked Potential (BAEP recording obtained with click and CE-chirp® stimuli and the presence or absence of waves I, III and V in high intensities. METHODS: Cross-sectional study with 12 adults with audiometric thresholds <15 dBHL (24 ears and mean age of 27 years. The parameters used for the recording with both stimuli in intensities of 80, 60, 40, 20 dBnHL were alternate polarity and repetition rate of 27.1 Hz. RESULTS: The CE-chirp® latencies for wave V were longer than click latencies at low intensity levels (20 and 40 dBnHL. At high intensity levels (60 and 80 dBnHL, the opposite occurred. Larger wave V amplitudes were observed with CE-chirp® in all intensity levels, except at 80 dBnHL. CONCLUSION: The CE-chirp® showed shorter latencies than those observed with clicks at high intensity levels and larger amplitudes at all intensity levels, except at 80 dBnHL. The waves I and III tended to disappear with CE-chirp® stimulation.

The EU's Normative Power in Changing World Politics

DEFF Research Database (Denmark)

Manners, Ian

2009-01-01

global order: 1) what is the concept of normative power in world politics?; 2) what is an effective EU toolbox for tackling new challenges?; 3) how does the EU go beyond self-perception and rhetoric?; 4) what is the raison d'etre of the EU?; and 5) how might normative power in EU external policies lead...

Auditory temporal preparation induced by rhythmic cues during concurrent auditory working memory tasks.

Science.gov (United States)

Cutanda, Diana; Correa, Ángel; Sanabria, Daniel

2015-06-01

The present study investigated whether participants can develop temporal preparation driven by auditory isochronous rhythms when concurrently performing an auditory working memory (WM) task. In Experiment 1, participants had to respond to an auditory target presented after a regular or an irregular sequence of auditory stimuli while concurrently performing a Sternberg-type WM task. Results showed that participants responded faster after regular compared with irregular rhythms and that this effect was not affected by WM load; however, the lack of a significant main effect of WM load made it difficult to draw any conclusion regarding the influence of the dual-task manipulation in Experiment 1. In order to enhance dual-task interference, Experiment 2 combined the auditory rhythm procedure with an auditory N-Back task, which required WM updating (monitoring and coding of the information) and was presumably more demanding than the mere rehearsal of the WM task used in Experiment 1. Results now clearly showed dual-task interference effects (slower reaction times [RTs] in the high- vs. the low-load condition). However, such interference did not affect temporal preparation induced by rhythms, with faster RTs after regular than after irregular sequences in the high-load and low-load conditions. These results revealed that secondary tasks demanding memory updating, relative to tasks just demanding rehearsal, produced larger interference effects on overall RTs in the auditory rhythm task. Nevertheless, rhythm regularity exerted a strong temporal preparation effect that survived the interference of the WM task even when both tasks competed for processing resources within the auditory modality. (c) 2015 APA, all rights reserved).

Prenatal IV Cocaine: Alterations in Auditory Information Processing

Directory of Open Access Journals (Sweden)

Charles F. Mactutus

2011-06-01

Full Text Available One clue regarding the basis of cocaine-induced deficits in attentional processing is provided by the clinical findings of changes in the infants’ startle response; observations buttressed by neurophysiological evidence of alterations in brainstem transmission time. Using the IV route of administration and doses that mimic the peak arterial levels of cocaine use in humans, the present study examined the effects of prenatal cocaine on auditory information processing via tests of the acoustic startle response (ASR, habituation, and prepulse inhibition (PPI in the offspring. Nulliparous Long-Evans female rats, implanted with an IV access port prior to breeding, were administered saline, 0.5, 1.0, or 3.0 mg/kg/injection of cocaine HCL (COC from gestation day (GD8-20 (1x/day-GD8-14, 2x/day-GD15-20. COC had no significant effects on maternal/litter parameters or growth of the offspring. At 18-20 days of age, one male and one female, randomly selected from each litter displayed an increased ASR (>30% for males at 1.0 mg/kg and >30% for females at 3.0 mg/kg. When reassessed in adulthood (D90-100, a linear dose-response increase was noted on response amplitude. At both test ages, within-session habituation was retarded by prenatal cocaine treatment. Testing the females in diestrus vs. estrus did not alter the results. Prenatal cocaine altered the PPI response function across interstimulus interval (ISI and induced significant sex-dependent changes in response latency. Idazoxan, an alpha2-adrenergic receptor antagonist, significantly enhanced the ASR, but less enhancement was noted with increasing doses of prenatal cocaine. Thus, in utero exposure to cocaine, when delivered via a protocol designed to capture prominent features of recreational usage, causes persistent, if not permanent, alterations in auditory information processing, and suggests dysfunction of the central noradrenergic circuitry modulating, if not mediating, these responses.

Short-term plasticity in auditory cognition.

Science.gov (United States)

Jääskeläinen, Iiro P; Ahveninen, Jyrki; Belliveau, John W; Raij, Tommi; Sams, Mikko

2007-12-01

Converging lines of evidence suggest that auditory system short-term plasticity can enable several perceptual and cognitive functions that have been previously considered as relatively distinct phenomena. Here we review recent findings suggesting that auditory stimulation, auditory selective attention and cross-modal effects of visual stimulation each cause transient excitatory and (surround) inhibitory modulations in the auditory cortex. These modulations might adaptively tune hierarchically organized sound feature maps of the auditory cortex (e.g. tonotopy), thus filtering relevant sounds during rapidly changing environmental and task demands. This could support auditory sensory memory, pre-attentive detection of sound novelty, enhanced perception during selective attention, influence of visual processing on auditory perception and longer-term plastic changes associated with perceptual learning.

Age-related auditory pathology in the CBA/J mouse

Science.gov (United States)

Sha, Su-Hua; Kanicki, Ariane; Dootz, Gary; Talaska, Andra E.; Halsey, Karin; Dolan, David; Altschuler, Richard; Schacht, Jochen

2008-01-01

Commercially obtained aged male CBA/J mice presented a complex pattern of hearing loss and morphological changes. A significant threshold shift in auditory brainstem responses (ABR) occurred at 3 months of age at 4 kHz without apparent loss of hair cells, rising slowly at later ages accompanied by loss of apical hair cells. A delayed high-frequency deficit started at 24 kHz around the age of 12 months. At 20 to 26 months, threshold shifts at 12 and 24 kHz and the accompanying hair cell loss at the base of the cochlea were highly variable with some animals appearing almost normal and others showing large deficits. Spiral ganglion cells degenerated by 18 months in all regions of the cochlea, with cell density reduced by approximately 25%. There was no degeneration of the stria vascularis and the endocochlear potential remained stable from 3 to 25 months of age regardless of whether the animals had normal or highly elevated ABR thresholds. The slow high frequency hearing loss combined with a modest reduction of ganglion cell density and an unchanged endocochlear potential suggest sensorineural presbycusis. The superimposed early hearing loss at low frequencies, which is not seen in animals bred in-house, may complicate the use of these animals as a presbycusis model. PMID:18573325

Auditory Processing Disorder (For Parents)

Science.gov (United States)

... role. Auditory cohesion problems: This is when higher-level listening tasks are difficult. Auditory cohesion skills — drawing inferences from conversations, understanding riddles, or comprehending verbal math problems — require heightened auditory processing and language levels. ...

The Effect of Working Memory Training on Auditory Stream Segregation in Auditory Processing Disorders Children

OpenAIRE

Abdollah Moossavi; Saeideh Mehrkian; Yones Lotfi; Soghrat Faghih zadeh; Hamed Adjedi

2015-01-01

Objectives: This study investigated the efficacy of working memory training for improving working memory capacity and related auditory stream segregation in auditory processing disorders children. Methods: Fifteen subjects (9-11 years), clinically diagnosed with auditory processing disorder participated in this non-randomized case-controlled trial. Working memory abilities and auditory stream segregation were evaluated prior to beginning and six weeks after completing the training program...

Lung inflammation induces IL-1β expression in hypoglossal neurons in rat brainstem

Science.gov (United States)

Jafri, Anjum; Belkadi, Abdelmadjid; Zaidi, Syed I. A.; Getsy, Paulina; Wilson, Christopher G.; Martin, Richard J.

2013-01-01

Perinatal inflammation is associated with respiratory morbidity. Immune modulation of brainstem respiratory control centers may provide a link for this pathobiology. We exposed 11-day old rats to intratracheal lipopolysaccharide (LPS, 0.5 µg/g) to test the hypothesis that intrapulmonary inflammation increases expression of the proinflammatory cytokine IL-1β within respiratory-related brainstem regions. Intratracheal LPS resulted in a 32% increase in IL-1β protein expression in the medulla oblongata. In situ hybridization showed increased intensity of IL-1β mRNA but no change in neuronal numbers. Co-localization experiments showed that hypoglossal neurons express IL-1β mRNA and immunostaining showed a 43% increase in IL-1β protein-expressing cells after LPS exposure. LPS treatment also significantly increased microglial cell numbers though they did not express IL-1β mRNA. LPS-induced brainstem expression of neuronal IL-1β mRNA and protein may have implications for our understanding of the vulnerability of neonatal respiratory control in response to a peripheral pro-inflammatory stimulus. PMID:23648475

The role of interpretation of existing practice in normative political argument

DEFF Research Database (Denmark)

Lægaard, Sune

2017-01-01

of contextualism and practice-dependence. The paper focuses on Andrea Sangiovanni’s methodological claims about social interpretation to illustrate both how facts can be part of the justification of principles and how interpretation is also faced with a number of problems as a way of justifying normative......In political theory concerned with normative evaluations and prescriptions facts can play two roles: (1) Facts can be of importance for the application of general normative principles to particular cases, and (2) facts can be of importance for the justification of normative principles as such...... principles. The paper finally argues that some of these problems can be avoided if one considers the two roles together; what enables interpretation of facts as part of the justification of normative principles precisely is that application and justification are not separate exercises....

The normative feedback approach for energy conservation behavior in the military community

International Nuclear Information System (INIS)

Shen, Meng; Young, Robert; Cui, Qingbin

2016-01-01

In the field of energy conservation programs, the behavior-based method, especially the normative feedback approach, has emerged as a cost-effective solution for energy savings. However it remains doubtful whether normative feedback would generate significant energy savings in absence of financial accountability and whether the normative feedback is influenced by the proximity of the comparison groups. Here we test various normative feedback approaches at the Joint Base Andrews in Maryland, with an objective of understanding this approach. We show that the normative feedback approach can lead to 3.4% energy savings, even when residents are not billed for their electricity usage. Through an analysis of covariance, this paper evaluates the effects of different proximities of comparison and concludes that a street-level comparison level can generate the highest energy savings of 5.4%. Furthermore, this paper also explores and defines the relationship between electricity savings and physical variables including home size, unit type, neighborhood, and the variation of cooling degree days. The study contributes to the understanding of how to realizing the full potential of normative feedback approach in energy savings. - Highlights: • Normative feedback leads to 3.4% energy savings even without financial incentives. • The study identifies the mere-exposure effect of normative feedback approach. • The street-level comparison doubles the energy savings compared to other levels. • Optimal normative feedback for energy saving should be compared at street-level. • Medium-sized homes in experiment show the greatest potential for energy savings.

Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

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Kutomi, Kimiko [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

2005-05-01

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)

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)

Novel Anterior Brainstem Magnetic Resonance Imaging Findings in Non-Small Cell Lung Cancer with Leptomeningeal Carcinomatosis

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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.

Modularity in Sensory Auditory Memory

OpenAIRE

Clement, Sylvain; Moroni, Christine; Samson, Séverine

2004-01-01

The goal of this paper was to review various experimental and neuropsychological studies that support the modular conception of auditory sensory memory or auditory short-term memory. Based on initial findings demonstrating that verbal sensory memory system can be dissociated from a general auditory memory store at the functional and anatomical levels. we reported a series of studies that provided evidence in favor of multiple auditory sensory stores specialized in retaining eit...

What determines auditory distraction? On the roles of local auditory changes and expectation violations.

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Jan P Röer

Full Text Available Both the acoustic variability of a distractor sequence and the degree to which it violates expectations are important determinants of auditory distraction. In four experiments we examined the relative contribution of local auditory changes on the one hand and expectation violations on the other hand in the disruption of serial recall by irrelevant sound. We present evidence for a greater disruption by auditory sequences ending in unexpected steady state distractor repetitions compared to auditory sequences with expected changing state endings even though the former contained fewer local changes. This effect was demonstrated with piano melodies (Experiment 1 and speech distractors (Experiment 2. Furthermore, it was replicated when the expectation violation occurred after the encoding of the target items (Experiment 3, indicating that the items' maintenance in short-term memory was disrupted by attentional capture and not their encoding. This seems to be primarily due to the violation of a model of the specific auditory distractor sequences because the effect vanishes and even reverses when the experiment provides no opportunity to build up a specific neural model about the distractor sequence (Experiment 4. Nevertheless, the violation of abstract long-term knowledge about auditory regularities seems to cause a small and transient capture effect: Disruption decreased markedly over the course of the experiments indicating that participants habituated to the unexpected distractor repetitions across trials. The overall pattern of results adds to the growing literature that the degree to which auditory distractors violate situation-specific expectations is a more important determinant of auditory distraction than the degree to which a distractor sequence contains local auditory changes.

Auditory-visual integration in fields of the auditory cortex.

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Kubota, Michinori; Sugimoto, Shunji; Hosokawa, Yutaka; Ojima, Hisayuki; Horikawa, Junsei

2017-03-01

While multimodal interactions have been known to exist in the early sensory cortices, the response properties and spatiotemporal organization of these interactions are poorly understood. To elucidate the characteristics of multimodal sensory interactions in the cerebral cortex, neuronal responses to visual stimuli with or without auditory stimuli were investigated in core and belt fields of guinea pig auditory cortex using real-time optical imaging with a voltage-sensitive dye. On average, visual responses consisted of short excitation followed by long inhibition. Although visual responses were observed in core and belt fields, there were regional and temporal differences in responses. The most salient visual responses were observed in the caudal belt fields, especially posterior (P) and dorsocaudal belt (DCB) fields. Visual responses emerged first in fields P and DCB and then spread rostroventrally to core and ventrocaudal belt (VCB) fields. Absolute values of positive and negative peak amplitudes of visual responses were both larger in fields P and DCB than in core and VCB fields. When combined visual and auditory stimuli were applied, fields P and DCB were more inhibited than core and VCB fields beginning approximately 110 ms after stimuli. Correspondingly, differences between responses to auditory stimuli alone and combined audiovisual stimuli became larger in fields P and DCB than in core and VCB fields after approximately 110 ms after stimuli. These data indicate that visual influences are most salient in fields P and DCB, which manifest mainly as inhibition, and that they enhance differences in auditory responses among fields. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

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Zahra Shahidipour

2014-01-01

Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

[Assessment of the efficiency of the auditory training in children with dyslalia and auditory processing disorders].

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Włodarczyk, Elżbieta; Szkiełkowska, Agata; Skarżyński, Henryk; Piłka, Adam

2011-01-01

To assess effectiveness of the auditory training in children with dyslalia and central auditory processing disorders. Material consisted of 50 children aged 7-9-years-old. Children with articulation disorders stayed under long-term speech therapy care in the Auditory and Phoniatrics Clinic. All children were examined by a laryngologist and a phoniatrician. Assessment included tonal and impedance audiometry and speech therapists' and psychologist's consultations. Additionally, a set of electrophysiological examinations was performed - registration of N2, P2, N2, P2, P300 waves and psychoacoustic test of central auditory functions: FPT - frequency pattern test. Next children took part in the regular auditory training and attended speech therapy. Speech assessment followed treatment and therapy, again psychoacoustic tests were performed and P300 cortical potentials were recorded. After that statistical analyses were performed. Analyses revealed that application of auditory training in patients with dyslalia and other central auditory disorders is very efficient. Auditory training may be a very efficient therapy supporting speech therapy in children suffering from dyslalia coexisting with articulation and central auditory disorders and in children with educational problems of audiogenic origin. Copyright © 2011 Polish Otolaryngology Society. Published by Elsevier Urban & Partner (Poland). All rights reserved.

Auditory Integration Training

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Zahra Jafari

2002-07-01

Full Text Available Auditory integration training (AIT is a hearing enhancement training process for sensory input anomalies found in individuals with autism, attention deficit hyperactive disorder, dyslexia, hyperactivity, learning disability, language impairments, pervasive developmental disorder, central auditory processing disorder, attention deficit disorder, depressin, and hyperacute hearing. AIT, recently introduced in the United States, and has received much notice of late following the release of The Sound of a Moracle, by Annabel Stehli. In her book, Mrs. Stehli describes before and after auditory integration training experiences with her daughter, who was diagnosed at age four as having autism.

Optimal technique of linear accelerator–based stereotactic radiosurgery for tumors adjacent to brainstem

International Nuclear Information System (INIS)

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 0.5 cm, and the other of 10 patients with a target-to-brainstem distance of ≥ 0.5 and < 1 cm. Comparison was then made among the following 3 types of LINAC-based radiosurgery: dynamic conformal arcs (DCA), intensity-modulated radiosurgery (IMRS), and volumetric modulated arc radiotherapy (VMAT). All techniques included multiple noncoplanar beams or arcs with or without intensity-modulated delivery. The volume of gross tumor volume (GTV) ranged from 0.2 cm 3 to 21.9 cm 3 . Regarding the dose homogeneity index (HI ICRU ) and conformity index (CI ICRU ) were without significant difference between techniques statistically. However, the average CI ICRU = 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 < 0.05). For V 4 Gy of brainstem, both VMAT (2.5%) and IMRS (2.7%) were significantly lower than DCA (4.9%), both at the p < 0.05 level. Regarding V 2 Gy of normal brain, VMAT plans had attained 6.4 ± 5%; this was significantly better

Normative Beliefs about Aggression as a Mediator of Narcissistic Exploitativeness and Cyberbullying

Science.gov (United States)

Ang, Rebecca P.; Tan, Kit-Aun; Mansor, Abu Talib

2011-01-01

The current study examined normative beliefs about aggression as a mediator between narcissistic exploitativeness and cyberbullying using two Asian adolescent samples from Singapore and Malaysia. Narcissistic exploitativeness was significantly and positively associated with cyberbullying and normative beliefs about aggression and normative beliefs…

Tracing How Normative Messages May Influence Physical Activity Intention.

Science.gov (United States)

van Bavel, René; Esposito, Gabriele; Baranowski, Tom; Duch-Brown, Néstor

2017-04-01

Normative messages have been shown to increase intention to do physical activity. We traced how "positive" and "negative" normative messages influenced physical activity intention by comparing constructs of the model of goal-directed behavior with descriptive norms (MGDB + DNs) across control and treatment groups in an experiment. For this purpose, 16-24-year-old respondents (n = 1,200) in Bulgaria, Croatia, and Romania were asked about their age, sex, and levels of physical activity before being exposed to positive and negative normative messages and completing a questionnaire with MGDB + DNs scales. Different MGDB + DNs constructs were influenced by the normative messages: compared with the control, the negative message group showed stronger attitudes (p = .003) and the positive message group showed higher positive anticipated emotions (p = .005). The positive message's effect is consistent with the literature on conformity to social norms. The negative message's effect lends itself to interpretations based on social identity and deviance regulation theories.

Reflecting on Normative Power Europe

DEFF Research Database (Denmark)

Diez, Thomas; Manners, Ian James

2014-01-01

-interested geographical expansion or military superiority. In the 1970s, François Duchêne called it a ‘civilian power’ (1972: 43); in the early 2000s it was argued that the label ‘normative power’ would be better suited (Manners 2000, 2002). Just as Duchêne’s civilian power reflected the Cold War milieu of the 1970s......There is a widespread belief that the European Union (EU) is a novel kind of power not only in its own institutional set-up but also in its external relations. It is said to rely on civilian rather than military means and to pursue the spread of particular norms rather than self......, the normative power approach signified a crystallisation of the EU in the post-Cold War era....

Contextualism in Normative Political Theory

DEFF Research Database (Denmark)

Lægaard, Sune

2016-01-01

Contextualism denotes a set of ideas about the importance of attention to context. The topic of the article is contextualism in normative political theory/philosophy, in relation to the part of political theory concerned with systematic political argument for normative claims—evaluative claims...... that can be invoked to contextualize a specific object of political discussion such as a law, an institution, or the like. Contextualism denotes any view that political theory should take context into account, but there are many different views about what this means. Contextualism can be characterized...... by way of different contrasts, which imply that the resulting conceptions of contextualism are views about different things, such as justification, the nature of political theory, or methodology. Here the focus is on characterizations of contextualism in terms of methodology and justification...

Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique.

Science.gov (United States)

Choudhri, Omar; Connolly, Ian D; Lawton, Michael T

2017-08-01

Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips. Copyright © 2017 by the Congress of Neurological Surgeons

Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area – an anterograde tract-tracing study

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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.

The normativity of artefacts

NARCIS (Netherlands)

Franssen, M.

2006-01-01

Part of the distinction between artefacts, objects made by humans for particular purposes, and natural objects is that artefacts are subject to normative judgements. A drill, say, can be a good drill or a poor drill, it can function well or correctly or it can malfunction. In this paper I

Normative reasons and the possibility of motivation | Luco | South ...

African Journals Online (AJOL)

... objects of psychological states –particularly beliefs, desires and intentions. In reply to the objection that normative reasons can never be objects of psychological states, I contend that all normative reasons are capable of being represented as the objects of psychological states. South African Journal of Philosophy 2014, ...

Neurodegenerative changes in the brainstem and olfactory bulb in people older than 50 years old: a descriptive study

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Francine Hehn de Oliveira

2015-07-01

Full Text Available With the increase in life expectancy in Brazil, concerns have grown about the most prevalent diseases in elderly people. Among these diseases are neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. Protein deposits related to the development of these diseases can pre-date the symptomatic phases by years. The tau protein is particularly interesting: it might be found in the brainstem and olfactory bulb long before it reaches the limbic cortex, at which point symptoms occur. Of the 14 brains collected in this study, the tau protein was found in the brainstems of 10 (71.42% and in olfactory bulbs of 3 out 11. Of the 7 individuals who had a final diagnosis of Alzheimer’s disease (AD, 6 presented tau deposits in some region of the brainstem. Our data support the idea of the presence of tau protein in the brainstem and olfactory bulb in the earliest stages of AD.

Bilingualism increases neural response consistency and attentional control: evidence for sensory and cognitive coupling.

Science.gov (United States)

Krizman, Jennifer; Skoe, Erika; Marian, Viorica; Kraus, Nina

2014-01-01

Auditory processing is presumed to be influenced by cognitive processes - including attentional control - in a top-down manner. In bilinguals, activation of both languages during daily communication hones inhibitory skills, which subsequently bolster attentional control. We hypothesize that the heightened attentional demands of bilingual communication strengthens connections between cognitive (i.e., attentional control) and auditory processing, leading to greater across-trial consistency in the auditory evoked response (i.e., neural consistency) in bilinguals. To assess this, we collected passively-elicited auditory evoked responses to the syllable [da] in adolescent Spanish-English bilinguals and English monolinguals and separately obtained measures of attentional control and language ability. Bilinguals demonstrated enhanced attentional control and more consistent brainstem and cortical responses. In bilinguals, but not monolinguals, brainstem consistency tracked with language proficiency and attentional control. We interpret these enhancements in neural consistency as the outcome of strengthened attentional control that emerged from experience communicating in two languages. Copyright © 2013 Elsevier Inc. All rights reserved.

A homozygous MYO7A mutation associated to Usher syndrome and unilateral auditory neuropathy spectrum disorder.

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Xia, Hong; Hu, Pengzhi; Yuan, Lamei; Xiong, Wei; Xu, Hongbo; Yi, Junhui; Yang, Zhijian; Deng, Xiong; Guo, Yi; Deng, Hao

2017-10-01

Usher syndrome (USH) is an autosomal recessive disorder characterized by sensorineural hearing loss, progressive visual loss and night blindness due to retinitis pigmentosa (RP), with or without vestibular dysfunction. The purpose of this study was to detect the causative gene in a consanguineous Chinese family with USH. A c.3696_3706del (p.R1232Sfs*72) variant in the myosin VIIa gene (MYO7A) was identified in the homozygous state by exome sequencing. The co‑segregation of the MYO7A c.3696_3706del variant with the phenotype of deafness and progressive visual loss in the USH family was confirmed by Sanger sequencing. The variant was absent in 200 healthy controls. Therefore, the c.3696_3706del variant may disrupt the interaction between myosin VIIa and other USH1 proteins, and impair melanosome transport in retinal pigment epithelial cells. Notably, bilateral auditory brainstem responses were absent in two patients of the USH family, while distortion product otoacoustic emissions were elicited in the right ears of the two patients, consistent with clinical diagnosis of unilateral auditory neuropathy spectrum disorder. These data suggested that the homozygous c.3696_3706del variant in the MYO7A gene may be the disease‑causing mutation for the disorder in this family. These findings broaden the phenotype spectrum of the MYO7A gene, and may facilitate understanding of the molecular pathogenesis of the disease, and genetic counseling for the family.

RECASTING THE NATURALISM–NORMATIVITY DEBATE: NEUROSCIENCE, NEUROPHILOSOPHY, NEUROETHICS

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Nythamar de Oliveira

2015-07-01

Full Text Available Assuming that there is a "neuroscientific turn" in moral philosophy, I will be discussing in this paper how neurophilosophy could shed light on the normative problems raised by a naturalistic project of ethical and social research, particularly related to the question of the articulation between the biological evolution of human species and the social and historical evolution of society and social groups. Taking a critical approach to naturalism and normative theories, I argue that there is a neurophenomenological deficit in naturalism (particularly in the versions of naturalism that follow the program of a naturalized epistemology and in the normative theories (particularly in the critical theory and I put forward a version of social constructivism that combines the neuroscientific and neurophilosophical models of Antonio Damasio and Jesse Prinz.

Amygdala and auditory cortex exhibit distinct sensitivity to relevant acoustic features of auditory emotions.

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Pannese, Alessia; Grandjean, Didier; Frühholz, Sascha

2016-12-01

Discriminating between auditory signals of different affective value is critical to successful social interaction. It is commonly held that acoustic decoding of such signals occurs in the auditory system, whereas affective decoding occurs in the amygdala. However, given that the amygdala receives direct subcortical projections that bypass the auditory cortex, it is possible that some acoustic decoding occurs in the amygdala as well, when the acoustic features are relevant for affective discrimination. We tested this hypothesis by combining functional neuroimaging with the neurophysiological phenomena of repetition suppression (RS) and repetition enhancement (RE) in human listeners. Our results show that both amygdala and auditory cortex responded differentially to physical voice features, suggesting that the amygdala and auditory cortex decode the affective quality of the voice not only by processing the emotional content from previously processed acoustic features, but also by processing the acoustic features themselves, when these are relevant to the identification of the voice's affective value. Specifically, we found that the auditory cortex is sensitive to spectral high-frequency voice cues when discriminating vocal anger from vocal fear and joy, whereas the amygdala is sensitive to vocal pitch when discriminating between negative vocal emotions (i.e., anger and fear). Vocal pitch is an instantaneously recognized voice feature, which is potentially transferred to the amygdala by direct subcortical projections. These results together provide evidence that, besides the auditory cortex, the amygdala too processes acoustic information, when this is relevant to the discrimination of auditory emotions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Neurochemical dynamics of acute orofacial pain in the human trigeminal brainstem nuclear complex.

Science.gov (United States)

de Matos, Nuno M P; Hock, Andreas; Wyss, Michael; Ettlin, Dominik A; Brügger, Mike

2017-11-15

The trigeminal brainstem sensory nuclear complex is the first central relay structure mediating orofacial somatosensory and nociceptive perception. Animal studies suggest a substantial involvement of neurochemical alterations at such basal CNS levels in acute and chronic pain processing. Translating this animal based knowledge to humans is challenging. Human related examining of brainstem functions are challenged by MR related peculiarities as well as applicability aspects of experimentally standardized paradigms. Based on our experience with an MR compatible human orofacial pain model, the aims of the present study were twofold: 1) from a technical perspective, the evaluation of proton magnetic resonance spectroscopy at 3 T regarding measurement accuracy of neurochemical profiles in this small brainstem nuclear complex and 2) the examination of possible neurochemical alterations induced by an experimental orofacial pain model. Data from 13 healthy volunteers aged 19-46 years were analyzed and revealed high quality spectra with significant reductions in total N-acetylaspartate (N-acetylaspartate + N-acetylaspartylglutamate) (-3.7%, p = 0.009) and GABA (-10.88%, p = 0.041) during the pain condition. These results might reflect contributions of N-acetylaspartate and N-acetylaspartylglutamate in neuronal activity-dependent physiologic processes and/or excitatory neurotransmission, whereas changes in GABA might indicate towards a reduction in tonic GABAergic functioning during nociceptive signaling. Summarized, the present study indicates the applicability of 1 H-MRS to obtain neurochemical dynamics within the human trigeminal brainstem sensory nuclear complex. Further developments are needed to pave the way towards bridging important animal based knowledge with human research to understand the neurochemistry of orofacial nociception and pain. Copyright © 2017 Elsevier Inc. All rights reserved.

Inter-trial coherence as a marker of cortical phase synchrony in children with sensorineural hearing loss and auditory neuropathy spectrum disorder fitted with hearing aids and cochlear implants

Science.gov (United States)

Nash-Kille, Amy; Sharma, Anu

2014-01-01

Objective Although brainstem dys-synchrony is a hallmark of children with auditory neuropathy spectrum disorder (ANSD), little is known about how the lack of neural synchrony manifests at more central levels. We used time-frequency single-trial EEG analyses (i.e., inter-trial coherence; ITC), to examine cortical phase synchrony in children with normal hearing (NH), sensorineural hearing loss (SNHL) and ANSD. Methods Single trial time-frequency analyses were performed on cortical auditory evoked responses from 41 NH children, 91 children with ANSD and 50 children with SNHL. The latter two groups included children who received intervention via hearing aids and cochlear implants. ITC measures were compared between groups as a function of hearing loss, intervention type, and cortical maturational status. Results In children with SNHL, ITC decreased as severity of hearing loss increased. Children with ANSD revealed lower levels of ITC relative to children with NH or SNHL, regardless of intervention. Children with ANSD who received cochlear implants showed significant improvements in ITC with increasing experience with their implants. Conclusions Cortical phase coherence is significantly reduced as a result of both severe-to-profound SNHL and ANSD. Significance ITC provides a window into the brain oscillations underlying the averaged cortical auditory evoked response. Our results provide a first description of deficits in cortical phase synchrony in children with SNHL and ANSD. PMID:24360131

Musical experience shapes top-down auditory mechanisms: evidence from masking and auditory attention performance.

Science.gov (United States)

Strait, Dana L; Kraus, Nina; Parbery-Clark, Alexandra; Ashley, Richard

2010-03-01

A growing body of research suggests that cognitive functions, such as attention and memory, drive perception by tuning sensory mechanisms to relevant acoustic features. Long-term musical experience also modulates lower-level auditory function, although the mechanisms by which this occurs remain uncertain. In order to tease apart the mechanisms that drive perceptual enhancements in musicians, we posed the question: do well-developed cognitive abilities fine-tune auditory perception in a top-down fashion? We administered a standardized battery of perceptual and cognitive tests to adult musicians and non-musicians, including tasks either more or less susceptible to cognitive control (e.g., backward versus simultaneous masking) and more or less dependent on auditory or visual processing (e.g., auditory versus visual attention). Outcomes indicate lower perceptual thresholds in musicians specifically for auditory tasks that relate with cognitive abilities, such as backward masking and auditory attention. These enhancements were observed in the absence of group differences for the simultaneous masking and visual attention tasks. Our results suggest that long-term musical practice strengthens cognitive functions and that these functions benefit auditory skills. Musical training bolsters higher-level mechanisms that, when impaired, relate to language and literacy deficits. Thus, musical training may serve to lessen the impact of these deficits by strengthening the corticofugal system for hearing. 2009 Elsevier B.V. All rights reserved.

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.)

Hunger, taste, and normative cues in predictions about food intake.

Science.gov (United States)

Vartanian, Lenny R; Reily, Natalie M; Spanos, Samantha; McGuirk, Lucy C; Herman, C Peter; Polivy, Janet

2017-09-01

Normative eating cues (portion size, social factors) have a powerful impact on people's food intake, but people often fail to acknowledge the influence of these cues, instead explaining their food intake in terms of internal (hunger) or sensory (taste) cues. This study examined whether the same biases apply when making predictions about how much food a person would eat. Participants (n = 364) read a series of vignettes describing an eating scenario and predicted how much food the target person would eat in each situation. Some scenarios consisted of a single eating cue (hunger, taste, or a normative cue) that would be expected to increase intake (e.g., high hunger) or decrease intake (e.g., a companion who eats very little). Other scenarios combined two cues that were in conflict with one another (e.g., high hunger + a companion who eats very little). In the cue-conflict scenarios involving an inhibitory internal/sensory cue (e.g., low hunger) with an augmenting normative cue (e.g., a companion who eats a lot), participants predicted a low level of food intake, suggesting a bias toward the internal/sensory cue. For scenarios involving an augmenting internal/sensory cue (e.g., high hunger) and an inhibitory normative cue (e.g., a companion who eats very little), participants predicted an intermediate level of food intake, suggesting that they were influenced by both the internal/sensory and normative cue. Overall, predictions about food intake tend to reflect a general bias toward internal/sensory cues, but also include normative cues when those cues are inhibitory. If people are systematically biased toward internal, sensory, and inhibitory cues, then they may underestimate how much food they or other people will eat in many situations, particularly when normative cues promoting eating are present. Copyright © 2017 Elsevier Ltd. All rights reserved.

Developmental programming of auditory learning

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Melania Puddu

2012-10-01

Full Text Available The basic structures involved in the development of auditory function and consequently in language acquisition are directed by genetic code, but the expression of individual genes may be altered by exposure to environmental factors, which if favorable, orient it in the proper direction, leading its development towards normality, if unfavorable, they deviate it from its physiological course. Early sensorial experience during the foetal period (i.e. intrauterine noise floor, sounds coming from the outside and attenuated by the uterine filter, particularly mother’s voice and modifications induced by it at the cochlear level represent the first example of programming in one of the earliest critical periods in development of the auditory system. This review will examine the factors that influence the developmental programming of auditory learning from the womb to the infancy. In particular it focuses on the following points: the prenatal auditory experience and the plastic phenomena presumably induced by it in the auditory system from the basilar membrane to the cortex;the involvement of these phenomena on language acquisition and on the perception of language communicative intention after birth;the consequences of auditory deprivation in critical periods of auditory development (i.e. premature interruption of foetal life.

The normativity of intentions

NARCIS (Netherlands)

Verbeek, B.J.E.

2013-01-01

Suppose you intend now to φ at some future time t. However, when t has come you do not φ. Something has gone wrong. This failing is not just a causal but also a normative failing. This raises the question how to characterize this failing. I discuss three alternative views. On the first view, the

Enterovirus 71 can directly infect the brainstem via cranial nerves and infection can be ameliorated by passive immunization.

Science.gov (United States)

Tan, Soon Hao; Ong, Kien Chai; Wong, Kum Thong

2014-11-01

Enterovirus 71 (EV71)-associated hand, foot, and mouth disease may be complicated by encephalomyelitis. We investigated EV71 brainstem infection and whether this infection could be ameliorated by passive immunization in a mouse model. Enterovirus 71 was injected into unilateral jaw/facial muscles of 2-week-old mice, and hyperimmune sera were given before or after infection. Harvested tissues were studied by light microscopy, immunohistochemistry, in situ hybridization, and viral titration. In unimmunized mice, viral antigen and RNA were detected within 24 hours after infection only in ipsilateral cranial nerves, motor trigeminal nucleus, reticular formation, and facial nucleus; viral titers were significantly higher in the brainstem than in the spinal cord samples. Mice given preinfection hyperimmune serum showed a marked reduction of ipsilateral viral antigen/RNA and viral titers in the brainstem in a dose-dependent manner. With optimum hyperimmune serum given after infection, brainstem infection was significantly reduced in a time-dependent manner. A delay in disease onset and a reduction of disease severity and mortality were also observed. Thus, EV71 can directly infect the brainstem, including the medulla, via cranial nerves, most likely by retrograde axonal transport. This may explain the sudden cardiorespiratory collapse in human patients with fatal encephalomyelitis. Moreover, our results suggest that passive immunization may still benefit EV71-infected patients who have neurologic complications.

Normative Data for Interpreting the BREAST-Q: Augmentation

Science.gov (United States)

Mundy, Lily R.; Homa, Karen; Klassen, Anne F.; Pusic, Andrea L.; Kerrigan, Carolyn L.

2016-01-01

Background The BREAST-Q is a rigorously developed, well-validated, patient-reported outcome (PRO) instrument with a module designed for evaluating breast augmentation outcomes. However, there are no published normative BREAST-Q scores, limiting interpretation. Methods Normative data were generated for the BREAST-Q Augmentation Module via the Army of Women (AOW), an online community of women (with and without breast cancer) engaged in breast-cancer related research. Members were recruited via email, with women 18 years or older without a history of breast cancer or breast surgery invited to participate. Descriptive statistics and a linear multivariate regression were performed. A separate analysis compared normative scores to findings from previously published BREAST-Q augmentation studies. Results The preoperative BREAST-Q Augmentation Module was completed by 1,211 women. Mean age was 54 ±24 years, mean body mass index (BMI) was 27 ±6, and 39% (n=467) had a bra cup size ≥D. Mean scores were Satisfaction with Breasts (54 ±19), Psychosocial Well-being (66 ±20), Sexual Well-being (49 ±20), and Physical Well-being (86 ±15). Women with a BMI of 30 or greater and bra cup size D or greater had lower scores. In comparison to AOW scores, published BREAST-Q augmentation scores were lower before and higher after surgery for all scales except Physical Well-being. Conclusions The AOW normative data represent breast-related satisfaction and well-being in woman not actively seeking breast augmentation. This data may be used as normative comparison values for those seeking and undergoing surgery as we did, demonstrating the value of breast augmentation in this patient population. PMID:28350657

Auditory short-term memory in the primate auditory cortex

OpenAIRE

Scott, Brian H.; Mishkin, Mortimer

2015-01-01

Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ���working memory��� bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive sho...

Individual differences in brainstem and basal ganglia structure predict postural control and balance loss in young and older adults.

Science.gov (United States)

Boisgontier, Matthieu P; Cheval, Boris; Chalavi, Sima; van Ruitenbeek, Peter; Leunissen, Inge; Levin, Oron; Nieuwboer, Alice; Swinnen, Stephan P

2017-02-01

It remains unclear which specific brain regions are the most critical for human postural control and balance, and whether they mediate the effect of age. Here, associations between postural performance and corticosubcortical brain regions were examined in young and older adults using multiple structural imaging and linear mixed models. Results showed that of the regions involved in posture, the brainstem was the strongest predictor of postural control and balance: lower brainstem volume predicted larger center of pressure deviation and higher odds of balance loss. Analyses of white and gray matter in the brainstem showed that the pedunculopontine nucleus area appeared to be critical for postural control in both young and older adults. In addition, the brainstem mediated the effect of age on postural control, underscoring the brainstem's fundamental role in aging. Conversely, lower basal ganglia volume predicted better postural performance, suggesting an association between greater neural resources in the basal ganglia and greater movement vigor, resulting in exaggerated postural adjustments. Finally, results showed that practice, shorter height and heavier weight (i.e., higher body mass index), higher total physical activity, and larger ankle active (but not passive) range of motion were predictive of more stable posture, irrespective of age. Copyright © 2016 Elsevier Inc. All rights reserved.

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

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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.

Integration of auditory and visual speech information

NARCIS (Netherlands)

Hall, M.; Smeele, P.M.T.; Kuhl, P.K.

1998-01-01

The integration of auditory and visual speech is observed when modes specify different places of articulation. Influences of auditory variation on integration were examined using consonant identifi-cation, plus quality and similarity ratings. Auditory identification predicted auditory-visual

Auditory Dysfunction in Patients with Cerebrovascular Disease

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Sadaharu Tabuchi

2014-01-01

Full Text Available Auditory dysfunction is a common clinical symptom that can induce profound effects on the quality of life of those affected. Cerebrovascular disease (CVD is the most prevalent neurological disorder today, but it has generally been considered a rare cause of auditory dysfunction. However, a substantial proportion of patients with stroke might have auditory dysfunction that has been underestimated due to difficulties with evaluation. The present study reviews relationships between auditory dysfunction and types of CVD including cerebral infarction, intracerebral hemorrhage, subarachnoid hemorrhage, cerebrovascular malformation, moyamoya disease, and superficial siderosis. Recent advances in the etiology, anatomy, and strategies to diagnose and treat these conditions are described. The numbers of patients with CVD accompanied by auditory dysfunction will increase as the population ages. Cerebrovascular diseases often include the auditory system, resulting in various types of auditory dysfunctions, such as unilateral or bilateral deafness, cortical deafness, pure word deafness, auditory agnosia, and auditory hallucinations, some of which are subtle and can only be detected by precise psychoacoustic and electrophysiological testing. The contribution of CVD to auditory dysfunction needs to be understood because CVD can be fatal if overlooked.

Anatomical parcellation of the brainstem and cerebellar white matter: a preliminary probabilistic tractography study at 3 T

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Habas, Christophe; Cabanis, Emmanuel A. [UPMC Paris 6, Service de NeuroImagerie, Hopital des Quinze-Vingts, Paris (France)

2007-10-15

The aims of this study were: (1) to test whether higher spatial resolution diffusion tensor images and a higher field strength (3 T) enable a more accurate delineation of the anatomical tract within the brainstem, and, in particular, (2) to try to distinguish the different components of the corticopontocerebellar paths in terms of their cortical origins. The main tracts of the brainstem of four volunteers were studied at 3 T using a probabilistic diffusion tensor imaging (DTI) axonal tracking. The resulting tractograms enabled anatomical well-delineated structures to be identified on the diffusion tensor coloured images. We tracked corticopontine, corticospinal, central tegmental, inferior and superior cerebellopeduncular, transverse, medial lemniscal and, possibly, longitudinal medial fibres. Moreover, DTI tracking allowed a broad delineation of the corticopontocerebellar paths. Diffusion tensor coloured images allow a rapid and reliable access to the white matter broad parcellation of the brainstem and of the cerebellum, which can be completed by fibre tracking. However, a more accurate and exhaustive depiction of the anatomical connectivity within the brainstem requires the application of more sophisticated techniques and tractography algorithms, such as diffusion spectrum imaging. (orig.)

Anatomical parcellation of the brainstem and cerebellar white matter: a preliminary probabilistic tractography study at 3 T

International Nuclear Information System (INIS)

Habas, Christophe; Cabanis, Emmanuel A.

2007-01-01

The aims of this study were: (1) to test whether higher spatial resolution diffusion tensor images and a higher field strength (3 T) enable a more accurate delineation of the anatomical tract within the brainstem, and, in particular, (2) to try to distinguish the different components of the corticopontocerebellar paths in terms of their cortical origins. The main tracts of the brainstem of four volunteers were studied at 3 T using a probabilistic diffusion tensor imaging (DTI) axonal tracking. The resulting tractograms enabled anatomical well-delineated structures to be identified on the diffusion tensor coloured images. We tracked corticopontine, corticospinal, central tegmental, inferior and superior cerebellopeduncular, transverse, medial lemniscal and, possibly, longitudinal medial fibres. Moreover, DTI tracking allowed a broad delineation of the corticopontocerebellar paths. Diffusion tensor coloured images allow a rapid and reliable access to the white matter broad parcellation of the brainstem and of the cerebellum, which can be completed by fibre tracking. However, a more accurate and exhaustive depiction of the anatomical connectivity within the brainstem requires the application of more sophisticated techniques and tractography algorithms, such as diffusion spectrum imaging. (orig.)

Weak responses to auditory feedback perturbation during articulation in persons who stutter: evidence for abnormal auditory-motor transformation.

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Shanqing Cai

Full Text Available Previous empirical observations have led researchers to propose that auditory feedback (the auditory perception of self-produced sounds when speaking functions abnormally in the speech motor systems of persons who stutter (PWS. Researchers have theorized that an important neural basis of stuttering is the aberrant integration of auditory information into incipient speech motor commands. Because of the circumstantial support for these hypotheses and the differences and contradictions between them, there is a need for carefully designed experiments that directly examine auditory-motor integration during speech production in PWS. In the current study, we used real-time manipulation of auditory feedback to directly investigate whether the speech motor system of PWS utilizes auditory feedback abnormally during articulation and to characterize potential deficits of this auditory-motor integration. Twenty-one PWS and 18 fluent control participants were recruited. Using a short-latency formant-perturbation system, we examined participants' compensatory responses to unanticipated perturbation of auditory feedback of the first formant frequency during the production of the monophthong [ε]. The PWS showed compensatory responses that were qualitatively similar to the controls' and had close-to-normal latencies (∼150 ms, but the magnitudes of their responses were substantially and significantly smaller than those of the control participants (by 47% on average, p<0.05. Measurements of auditory acuity indicate that the weaker-than-normal compensatory responses in PWS were not attributable to a deficit in low-level auditory processing. These findings are consistent with the hypothesis that stuttering is associated with functional defects in the inverse models responsible for the transformation from the domain of auditory targets and auditory error information into the domain of speech motor commands.

Neurath's ship: The constitutive relation between normative and descriptive theories of rationality

OpenAIRE

Waldmann, Michael R.

2011-01-01

I defend the claim that in psychological theories concerned with theoretical or practical rationality there is a constitutive relation between normative and descriptive theories: Normative theories provide idealized descriptive accounts of rational agents. However, we need to resist the temptation to collapse descriptive theories with any specific normative theory. I show how a partial separation is possible. peerReviewed

Developmental changes in children's normative reasoning across learning contexts and collaborative roles.

Science.gov (United States)

Riggs, Anne E; Young, Andrew G

2016-08-01

What influences children's normative judgments of conventional rules at different points in development? The current study explored the effects of two contextual factors on children's normative reasoning: the way in which the rules were learned and whether the rules apply to the self or others. Peer dyads practiced a novel collaborative board game comprising two complementary roles. Dyads were either taught both the prescriptive (i.e., what to do) and proscriptive (i.e., what not to do) forms of the rules, taught only the prescriptive form of the rules, or created the rules themselves. Children then judged whether third parties were violating or conforming to the rules governing their own roles and their partner's roles. Early school-aged children's (6- to 7-year-olds; N = 60) normative judgments were strongest when they had been taught the rules (with or without the proscriptive form), but were more flexible for rules they created themselves. Preschool-aged children's (4- to 5-year-olds; N = 60) normative judgments, however, were strongest when they were taught both the prescriptive and proscriptive forms of the rules. Additionally, preschoolers exhibited stronger normative judgments when the rules governed their own roles rather than their partner's roles, whereas school-aged children treated all rules as equally normative. These results demonstrate that children's normative reasoning is contingent on contextual factors of the learning environment and, moreover, highlight 2 specific areas in which children's inferences about the normativity of conventions strengthen over development. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Normative Power Europe and the Importance of the Discursive Context

DEFF Research Database (Denmark)

Larsen, Henrik

2014-01-01

Europe, with the notable exceptions of Diez (2013); Keene (2012); Forsberg (2011) and Huelss (2011) (who also discuss the meaning of the ‘normative’). Focusing on power, the question asked in this article is how the discursive context of the politics of religion affects the EU’s ability to exert......This article attempts to demonstrate the importance of the discursive context for whether and, if so, how the European Union (EU) can exert normative power in different policy areas. Surprisingly, the concept of power has not been extensively discussed in the academic literature on Normative Power...... normative power in this area. The article examines the politics of religion by looking at the case of the debate about human rights versus religion in the United Nations Human Rights Council after the year 2000. The broader point addressed in the article is whether the EU can exert normative power...

Integration of Visual Information in Auditory Cortex Promotes Auditory Scene Analysis through Multisensory Binding.

Science.gov (United States)

Atilgan, Huriye; Town, Stephen M; Wood, Katherine C; Jones, Gareth P; Maddox, Ross K; Lee, Adrian K C; Bizley, Jennifer K

2018-02-07

How and where in the brain audio-visual signals are bound to create multimodal objects remains unknown. One hypothesis is that temporal coherence between dynamic multisensory signals provides a mechanism for binding stimulus features across sensory modalities. Here, we report that when the luminance of a visual stimulus is temporally coherent with the amplitude fluctuations of one sound in a mixture, the representation of that sound is enhanced in auditory cortex. Critically, this enhancement extends to include both binding and non-binding features of the sound. We demonstrate that visual information conveyed from visual cortex via the phase of the local field potential is combined with auditory information within auditory cortex. These data provide evidence that early cross-sensory binding provides a bottom-up mechanism for the formation of cross-sensory objects and that one role for multisensory binding in auditory cortex is to support auditory scene analysis. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Interaction of language, auditory and memory brain networks in auditory verbal hallucinations

NARCIS (Netherlands)

Curcic-Blake, Branislava; Ford, Judith M.; Hubl, Daniela; Orlov, Natasza D.; Sommer, Iris E.; Waters, Flavie; Allen, Paul; Jardri, Renaud; Woodruff, Peter W.; David, Olivier; Mulert, Christoph; Woodward, Todd S.; Aleman, Andre

Auditory verbal hallucinations (AVH) occur in psychotic disorders, but also as a symptom of other conditions and even in healthy people. Several current theories on the origin of AVH converge, with neuroimaging studies suggesting that the language, auditory and memory/limbic networks are of

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

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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

Procedures for central auditory processing screening in schoolchildren.

Science.gov (United States)

Carvalho, Nádia Giulian de; Ubiali, Thalita; Amaral, Maria Isabel Ramos do; Santos, Maria Francisca Colella

2018-03-22

Central auditory processing screening in schoolchildren has led to debates in literature, both regarding the protocol to be used and the importance of actions aimed at prevention and promotion of auditory health. Defining effective screening procedures for central auditory processing is a challenge in Audiology. This study aimed to analyze the scientific research on central auditory processing screening and discuss the effectiveness of the procedures utilized. A search was performed in the SciELO and PUBMed databases by two researchers. The descriptors used in Portuguese and English were: auditory processing, screening, hearing, auditory perception, children, auditory tests and their respective terms in Portuguese. original articles involving schoolchildren, auditory screening of central auditory skills and articles in Portuguese or English. studies with adult and/or neonatal populations, peripheral auditory screening only, and duplicate articles. After applying the described criteria, 11 articles were included. At the international level, central auditory processing screening methods used were: screening test for auditory processing disorder and its revised version, screening test for auditory processing, scale of auditory behaviors, children's auditory performance scale and Feather Squadron. In the Brazilian scenario, the procedures used were the simplified auditory processing assessment and Zaidan's battery of tests. At the international level, the screening test for auditory processing and Feather Squadron batteries stand out as the most comprehensive evaluation of hearing skills. At the national level, there is a paucity of studies that use methods evaluating more than four skills, and are normalized by age group. The use of simplified auditory processing assessment and questionnaires can be complementary in the search for an easy access and low-cost alternative in the auditory screening of Brazilian schoolchildren. Interactive tools should be proposed, that

Talking back: Development of the olivocochlear efferent system.

Science.gov (United States)

Frank, Michelle M; Goodrich, Lisa V

2018-06-26

Developing sensory systems must coordinate the growth of neural circuitry spanning from receptors in the peripheral nervous system (PNS) to multilayered networks within the central nervous system (CNS). This breadth presents particular challenges, as nascent processes must navigate across the CNS-PNS boundary and coalesce into a tightly intermingled wiring pattern, thereby enabling reliable integration from the PNS to the CNS and back. In the auditory system, feedforward spiral ganglion neurons (SGNs) from the periphery collect sound information via tonotopically organized connections in the cochlea and transmit this information to the brainstem for processing via the VIII cranial nerve. In turn, feedback olivocochlear neurons (OCNs) housed in the auditory brainstem send projections into the periphery, also through the VIII nerve. OCNs are motor neuron-like efferent cells that influence auditory processing within the cochlea and protect against noise damage in adult animals. These aligned feedforward and feedback systems develop in parallel, with SGN central axons reaching the developing auditory brainstem around the same time that the OCN axons extend out toward the developing inner ear. Recent findings have begun to unravel the genetic and molecular mechanisms that guide OCN development, from their origins in a generic pool of motor neuron precursors to their specialized roles as modulators of cochlear activity. One recurrent theme is the importance of efferent-afferent interactions, as afferent SGNs guide OCNs to their final locations within the sensory epithelium, and efferent OCNs shape the activity of the developing auditory system. This article is categorized under: Nervous System Development > Vertebrates: Regional Development. © 2018 Wiley Periodicals, Inc.

Auditory prediction during speaking and listening.

Science.gov (United States)

Sato, Marc; Shiller, Douglas M

2018-02-02

In the present EEG study, the role of auditory prediction in speech was explored through the comparison of auditory cortical responses during active speaking and passive listening to the same acoustic speech signals. Two manipulations of sensory prediction accuracy were used during the speaking task: (1) a real-time change in vowel F1 feedback (reducing prediction accuracy relative to unaltered feedback) and (2) presenting a stable auditory target rather than a visual cue to speak (enhancing auditory prediction accuracy during baseline productions, and potentially enhancing the perturbing effect of altered feedback). While subjects compensated for the F1 manipulation, no difference between the auditory-cue and visual-cue conditions were found. Under visually-cued conditions, reduced N1/P2 amplitude was observed during speaking vs. listening, reflecting a motor-to-sensory prediction. In addition, a significant correlation was observed between the magnitude of behavioral compensatory F1 response and the magnitude of this speaking induced suppression (SIS) for P2 during the altered auditory feedback phase, where a stronger compensatory decrease in F1 was associated with a stronger the SIS effect. Finally, under the auditory-cued condition, an auditory repetition-suppression effect was observed in N1/P2 amplitude during the listening task but not active speaking, suggesting that auditory predictive processes during speaking and passive listening are functionally distinct. Copyright © 2018 Elsevier Inc. All rights reserved.

The Rey Auditory Verbal Learning Test forced-choice recognition task: Base-rate data and norms.

Science.gov (United States)

Poreh, Amir; Bezdicek, Ondrej; Korobkova, Irina; Levin, Jennifer B; Dines, Philipp

2016-01-01

The present study describes a novel Forced-Choice Response (FCR) index for detecting poor effort on the Rey Auditory Verbal Learning Test (RAVLT). This retrospective study analyzes the performance of 4 groups on the new index: clinically referred patients with suspected dementia, forensic patients identified as not exhibiting adequate effort on other measures of response bias, students who simulated poor effort, and a large normative sample collected in the Gulf State of Oman. Using sensitivity and specificity analyses, the study shows that much like the California Verbal Learning Test-Second Edition FCR index, the RAVLT FCR index misses a proportion of individuals with inadequate effort (low sensitivity), but those who fail this measure are highly likely to be exhibiting poor effort (high specificity). The limitations and benefits of utilizing the RAVLT FCR index in clinical practice are discussed.

Adaptation in the auditory system: an overview

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David ePérez-González

2014-02-01

Full Text Available The early stages of the auditory system need to preserve the timing information of sounds in order to extract the basic features of acoustic stimuli. At the same time, different processes of neuronal adaptation occur at several levels to further process the auditory information. For instance, auditory nerve fiber responses already experience adaptation of their firing rates, a type of response that can be found in many other auditory nuclei and may be useful for emphasizing the onset of the stimuli. However, it is at higher levels in the auditory hierarchy where more sophisticated types of neuronal processing take place. For example, stimulus-specific adaptation, where neurons show adaptation to frequent, repetitive stimuli, but maintain their responsiveness to stimuli with different physical characteristics, thus representing a distinct kind of processing that may play a role in change and deviance detection. In the auditory cortex, adaptation takes more elaborate forms, and contributes to the processing of complex sequences, auditory scene analysis and attention. Here we review the multiple types of adaptation that occur in the auditory system, which are part of the pool of resources that the neurons employ to process the auditory scene, and are critical to a proper understanding of the neuronal mechanisms that govern auditory perception.

Sequential change in MRI in two cases with small brainstem infarctions

International Nuclear Information System (INIS)

Masuda, Ryoichi; Fukuda, Osamu; Endoh, Shunro; Takaku, Akira; Suzuki, Takashi; Satoh, Shuji

1987-01-01

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. (author)

Intermittent hypercapnic hypoxia effects on the nicotinic acetylcholine receptors in the developing piglet hippocampus and brainstem.

Science.gov (United States)

Vivekanandarajah, Arunnjah; Aishah, Atqiya; Waters, Karen A; Machaalani, Rita

2017-05-01

This study investigated the effects of acute (1 day) vs repeated (4 days) exposure to intermittent hypercapnic hypoxia (IHH) on the immunohistochemical expression of α2, α3, α5, α7, α9 and β2 nicotinic acetylcholine receptor (nAChR) subunits in the developing piglet hippocampus and brainstem medulla, and how prior nicotine exposure alters the response to acute IHH. Five piglet groups included: 1day IHH (1D IHH, n=9), 4days IHH (4D IHH, n=8), controls exposed only to air cycles for 1day (1D Air, n=6) or 4days (4D Air, n=5), and pre-exposed to nicotine for 13days prior to 1day IHH (Nic+1D IHH, n=7). The exposure period alternated 6min of HH (8%O 2 , 7%CO 2 , balance N 2 ) and 6min of air over 48min, while controls were switched from air-to-air. Results showed that: 1. repeated IHH induces more changes in nAChR subunit expression than acute IHH in both the hippocampus and brainstem medulla, 2. In the hippocampus, α2 and β2 changed the most (increased) following IHH and the CA3, CA2 and DG were mostly affected. In the brainstem medulla, α2, α5, α9 and β2 were changed (decreased) in most nuclei with the hypoglossal and nucleus of the solitary tract being mostly affected. 3. Pre-exposure to nicotine enhanced the changes in the hippocampus but dampened those in the brainstem medulla. These findings indicate that the nAChRs (predominantly with the α2/β2 complex) are affected by IHH in critical hippocampal and brainstem nuclei during early brain development, and that pre-exposure to nicotine alters the pattern of susceptibility to IHH. Copyright © 2017 Elsevier B.V. All rights reserved.

Relationship between boys' normative beliefs about aggression and their physical, verbal, and indirect aggressive behaviors.

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Lim, Si Huan; Ang, Rebecca P

2009-01-01

This study examined the contribution of general normative beliefs about aggression and specific normative beliefs about retaliatory aggression in predicting physical, verbal, and indirect aggressive behaviors. Two hundred and forty-nine Grade 4 and Grade 5 boys completed the Normative Beliefs about Aggression Scale (NOBAGS) and provided self-reports on the frequency of their physical, verbal, and indirect aggressive behaviors. A series of hierarchical multiple regression analyses revealed that general normative beliefs about aggression contributed significantly in predicting all three types of aggressive behaviors. When general normative beliefs about aggression were controlled for, specific normative beliefs about retaliatory aggression against males but not specific normative beliefs about retaliatory aggression against females, contributed significantly to predict physical, verbal, and indirect aggressive behaviors. Implications for intervention programs are discussed.

Effects of Fish Oil Supplementation during the Suckling Period on Auditory Neural Conduction in n-3 Fatty Acid-Deficient Rat Pups

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vida rahimi

2014-07-01

Full Text Available Abstract Introduction: Omega 3 fatty acid especially in the form of fish oil, has structural and biological role in the body's various systems especially nervous system. Numerous studies have tried to research about it. Auditory is one of the affected systems. Omega 3 deficiency can have devastating effects on the nervous system and auditory. This study aimed to evaluate neural conduction in n-3 fatty acid-deficient rat pups following the supplementation of fish oil consumption during the suckling period Materials and Methods: In this interventional and experimental study, one sources of omega3 fatty acid (fish oil were fed to rat pups of n-3 PUFA-deficient dams to compare changes in their auditory neural conduction with that of control and n-3 PUFA-deficient groups, using Auditory Brainstem Response (ABR. The parameters of interest were P1, P3, P4 absolute latency, P1-P3, P1-P4 and P3-P4 IPL , P4/P1 amplitude ratio . The rat pups were given oral fish oil, 5 Ml /g weight for 17 days, between the age of 5 and 21 days. Results There were no significant group differences in P1 and P3 absolute latency (p > 0.05. but the result in P4 was significant(P ≤ 0.05 . The n-3 PUFA deficient +vehicle had the most prolonged (the worst P1-P4 IPL and P3-P4 IPL compared with control and n-3 PUFA deficient + FO groups. There was no significant difference in P1-P4 IPL and P3-P4 IPL between n-3 PUFA deficient + FO and control groups (p > 0.05.There was a significant effect of diet on P1-P4 IPL and P3-P4 IPL between groups (P ≤ 0.05. Conclusion: The results of present study showed the effect of omega3 deficiency on auditory neural structure during pregnancy and lactation period. Additionally, we observed the reduced devastating effects on neural conduction in n-3 fatty acid-deficient rat pups following the supplementation of fish oil during the suckling period

Developing a normative critique of international trade law: special & differential treatment

OpenAIRE

Garcia, Frank J.

2007-01-01

Although the problem of trade and inequality is central to the resolution of the WTO Doha Round and to contemporary trade policy in general, it is currently undertheorized from a normative perspective. In this paper I develop a normative critique of WTO special and differential treatment law, as a case study of how normative political theory can be applied to international economic law. Using Rawls' theory of Justice as Fairness, I argue both that special and differential treatment can play a...

Normative influence on condom use in the personal networks of female cocaine smokers.

Science.gov (United States)

Richard, A J; Bell, D C; Montoya, I D

2000-08-01

Attitudes-norms research (the theories of planned behavior and reasoned action) has been successful in accounting for many types of behavior change. One of the strengths of this approach has been to combine individual beliefs and normative influences in the explanation of behavior change. However, the conceptualization of normative influence in these theories makes very strong assumptions about self-awareness in the selection of normative referents. These assumptions are particularly problematic when applied to female cocaine smokers, who report frequent sex while under duress or while cognitively impaired. In this study the original conceptualization of normative influence and two alternatives (assuming emotion-based and interaction-based selection of normative referents) are operationalized to evaluate stage of change for condom use among women who are heavy crack cocaine users with multiple sex partners. Results show that stage of change for use of condoms with nonmain partners is best accounted for by interaction-based selection of normative referents.