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Sample records for brainstem auditory evoked

  1. BAER - brainstem auditory evoked response

    Science.gov (United States)

    ... auditory potentials; Brainstem auditory evoked potentials; Evoked response audiometry; Auditory brainstem response; ABR; BAEP ... Normal results vary. Results will depend on the person and the instruments used to perform the test.

  2. Speech Evoked Auditory Brainstem Response in Stuttering

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    Ali Akbar Tahaei

    2014-01-01

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

  3. Brainstem auditory evoked potentials in children with lead exposure

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    Katia de Freitas Alvarenga

    2015-02-01

    Full Text Available Introduction: Earlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated. Objective: To investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test. Methods: Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months ± 3 years, 2 months. Results: The mean time-integrated cumulative blood lead index was 12 µg/dL (SD ± 5.7, range:2.433. All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I-III, III-V, and I-V, and the cumulative lead values. Conclusion: No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area.

  4. Brainstem auditory evoked potentials in children with lead exposure.

    Science.gov (United States)

    Alvarenga, Katia de Freitas; Morata, Thais Catalani; Lopes, Andrea Cintra; Feniman, Mariza Ribeiro; Corteletti, Lilian Cassia Bornia Jacob

    2015-01-01

    Earlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated. To investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test. Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months ± 3 years, 2 months). The mean time-integrated cumulative blood lead index was 12 μg/dL (SD ± 5.7, range: 2.433). All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I-III, III-V, and I-V, and the cumulative lead values. No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  5. EVALUATION OF BRAINSTEM AUDITORY EVOKED POTENTIAL IN MIGRAINE PATIENT

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    Sowmiya R, Vinodha R

    2015-10-01

    Full Text Available Background: Migraine is worldwide common, chronic, Neurovascular disorder, characterized by attacks of severe headache and an Aura involving neurologic symptoms. Its pathogenesis was incompletely understood whether of cortical or brainstem origin. Aim: The present study was undertaken to investigate brainstem auditory functions in Migraine patients. Materials and Methods: The subjects were recruited based on International Headache Society classification for Migraine. Subjects with episodes of headache for at least 2yrs, 2 attacks per month in last quarter year were included in the study. Forty subjects (16 Migraine with Aura & 24 cases – Migraine without aura & forty age / sex matched controls were selected. Brainstem auditory evoked potential was recorded using 4-Channel polygraph (Neuro perfect plus. Electrodes were placed according to 10 – 20 electrode placement system. Auditory stimulus in the form of click sound is delivered through the headphones. Clicks were delivered at a rate of 8-10 /sec. The intensity of the stimulus is set at 30db. About 100 averages were recorded. BAEP waveforms – Wave I, III & V latencies and the interpeak latencies were measured. The results were analysed statistically using student‘t’ test. Results: BAEP recording shows significant prolongation in latencies of Wave I, III & V and the Interpeak latency (IPL I-III, III-V & I-V in Migraine with aura. In Migraine without aura, there was significant prolongation of Wave I, III & V and III-V & I-VIPL (P<0.05. Conclusion: Prolongation suggests that there is involvement of brainstem structures in Migraine, thus BAEP can be used as an effective tool in evaluation of Migraine.

  6. 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.

  7. Modeling auditory evoked brainstem responses to transient stimuli

    DEFF Research Database (Denmark)

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

    2012-01-01

    A quantitative model is presented that describes the formation of auditory brainstem responses (ABR) to tone pulses, clicks and rising chirps as a function of stimulation level. The model computes the convolution of the instantaneous discharge rates using the “humanized” nonlinear auditory-nerve ...

  8. Brainstem auditory-evoked potential in Boxer dogs

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    Mariana Isa Poci Palumbo

    2014-10-01

    Full Text Available Brainstem auditory-evoked potential (BAEP has been widely used for different purposes in veterinary practice and is commonly used to identify inherited deafness and presbycusis. In this study, 43 Boxer dogs were evaluated using the BAEP. Deafness was diagnosed in 3 dogs (2 bilateral and 1 unilateral allowing the remaining 40 Boxers to be included for normative data analysis including an evaluation on the influence of age on the BAEP. The animals were divided into 2 groups of 20 Boxers each based on age. The mean age was 4.54 years (range, 1-8 in group I, and 9.83 years (range, 8.5-12 in group II. The mean latency for I, III, and V waves were 1.14 (±0.07, 2.64 (±0.11, and 3.48 (±0.10 ms in group I, and 1.20 (±0.12, 2.73 (±0.15, and 3.58 (±0.22 ms in group II, respectively. The mean inter-peak latencies for the I-III, III-V and I-V intervals were 1.50 (±0.15, 0.84 (±0.15, and 2.34 (±0.11 ms in group I, and 1.53 (±0.16, 0.85 (±0.15, and 2.38 (±0.19 ms in group II, respectively. Latencies of waves I and III were significant different between group I and II. For the I-III, III-V and I-V intervals, no significant differences were observed between the 2 groups. As far as we know, this is the first normative study of BAEP obtained from Boxer dogs.

  9. Brainstem auditory evoked responses in 37 dogs with otitis media before and after topical therapy.

    Science.gov (United States)

    Paterson, S

    2017-07-18

    The objective of this study was to determine whether intra-aural administration of aqueous solutions of marbofloxacin, gentamicin, tobramycin and ticarcillin (used off-licence) was associated with changes in hearing as measured by brainstem auditory evoked responses. Dogs diagnosed with otitis media (n=37) underwent brainstem auditory evoked response testing and then were treated for their ear disease. First, the external ear canal and middle ear were flushed with sterile saline followed by EDTA tris with 0·15% chlorhexidine. Then, a combination of aqueous antibiotic mixed with an aqueous solution of EDTA tris was instilled into the middle ear. Follow-up examinations were undertaken for each dog, and treatment was continued until there were no detected infectious organisms or inflammatory infiltrate. Brainstem auditory evoked response testing was repeated after resolution of the infection and discontinuation of therapy. Brainstem auditory evoked responses in dogs treated with aqueous solutions of marbofloxacin or gentamicin remained unchanged or improved after therapy of otitis media but were impaired in dogs treated with ticarcillin or tobramycin. If off-licence use of topical antibiotics is deemed necessary in cases of otitis media, aqueous solutions of marbofloxacin and gentamicin appear to be less ototoxic than aqueous solutions of ticarcillin or tobramycin. © 2017 British Small Animal Veterinary Association.

  10. Brainstem Auditory Evoked Potentials in Patients with Subarachnoid Haemorrhage

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    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.

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

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    He, Wenxin; Ding, Xiuyong; Zhang, Ruxiang; Chen, Jing; Zhang, Daoxing; Wu, Xihong

    2014-01-01

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

  12. [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 (Pbrain concussion was 73.7%, indicating dysfunction of the brainstem in those patients. BAEP might be helpful in forensic diagnosis of brain concussion.

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

    Science.gov (United States)

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

    2017-08-01

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

  14. Changes in brainstem auditory evoked potentials among North Indian females with Type 2 diabetes mellitus

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    Pooja Baweja

    2013-01-01

    Full Text Available Background: Diabetes mellitus is a complex metabolic disorder whose detrimental effects on various organ systems, including the nervous system are well known. Aim: This study was conducted to determine the changes in the brainstem auditory evoked potentials (BAEP in patients with type 2 diabetes mellitus. Materials and Methods: In this case-control study, 116 females with type 2 diabetes and 100 age matched, healthy female volunteers were selected. The brainstem auditory evoked potentials (BAEP were recorded with RMS EMG EP Marc-II Channel machine. The measures included latencies of waves I, II, III, IV, V and Interpeak latencies (IPL I-III, III-V and I-V separately for both ears. Data was analysed statistically with SPSS software v13.0. Results: It was found that IPL I-III was significantly delayed (P = 0.028 only in the right ear, while the latency of wave V and IPL I-V showed a significant delay bilaterally (P values for right ear being 0.021 and 0.0381 respectively while those for left ear being 0.028 and 0.016 respectively, in diabetic females. However, no significant difference (P > 0.05 was found between diabetic and control subjects as regards to the latencies of waves I, II, III, IV and IPL III-V bilaterally and IPL I-III unilaterally in the left ear. Also, none of the BAEP latencies were significantly correlated with either the duration of disease or with fasting blood glucose levels in diabetics. Conclusions: Therefore, it could be concluded that diabetes patients have an early involvement of central auditory pathway, which can be detected quite accurately with the help of auditory evoked potential studies.

  15. Infant temperament and the brainstem auditory evoked response in later childhood.

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    Woodward, S A; McManis, M H; Kagan, J; Deldin, P; Snidman, N; Lewis, M; Kahn, V

    2001-07-01

    Brainstem auditory evoked responses (BAERs) were evaluated on 10-12-year-old children (N = 56) who had been classified as high or low reactive to unfamiliar stimuli at 4 months of age. BAER measurement was selected because high reactive infants tend to become inhibited or fearful young children, and adult introverts have a faster latency to wave V of the BAER than do extroverts. Children previously classified as high reactive at 4 months had larger wave V components than did low reactive children, a finding that possibly suggests greater excitability in projections to the inferior colliculus. The fact that a fundamental feature of brainstem activity differentiated preadolescent children belonging to two early temperamental groups supports the value of gathering physiological data in temperament research.

  16. Comparison of binaural auditory brainstem responses and the binaural difference potential evoked by chirps and clicks.

    Science.gov (United States)

    Riedel, Helmut; Kollmeier, Birger

    2002-07-01

    Rising chirps that compensate for the dispersion of the travelling wave on the basilar membrane evoke larger monaural brainstem responses than clicks. In order to test if a similar effect applies for the early processing stages of binaural information, monaurally and binaurally evoked auditory brainstem responses were recorded for clicks and chirps for levels from 10 to 60 dB nHL in steps of 10 dB. Ten thousand sweeps were collected for every stimulus condition from 10 normal hearing subjects. Wave V amplitudes are significantly larger for chirps than for clicks for all conditions. The amplitude of the binaural difference potential, DP1-DN1, is significantly larger for chirps at the levels 30 and 40 dB nHL. Both the binaurally evoked potential and the binaural difference potential exhibit steeper growth functions for chirps than for clicks for levels up to 40 dB nHL. For higher stimulation levels the chirp responses saturate approaching the click evoked amplitude. For both stimuli the latency of DP1 is shorter than the latency of the binaural wave V, which in turn is shorter than the latency of DN1. The amplitude ratio of the binaural difference potential to the binaural response is independent of stimulus level for clicks and chirps. A possible interpretation is that with click stimulation predominantly binaural interaction from high frequency regions is seen which is compatible with a processing by contralateral inhibitory and ipsilateral excitatory (IE) cells. Contributions from low frequencies are negligible since the responses from low frequencies are not synchronized for clicks. The improved synchronization at lower frequencies using chirp stimuli yields contributions from both low and high frequency neurons enlarging the amplitudes of the binaural responses as well as the binaural difference potential. Since the constant amplitude ratio of the binaural difference potential to the binaural response makes contralateral and ipsilateral excitatory interaction

  17. Brainstem Evoked Potential Indices of Subcortical Auditory Processing After Mild Traumatic Brain Injury.

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    Vander Werff, Kathy R; Rieger, Brian

    The primary aim of this study was to assess subcortical auditory processing in individuals with chronic symptoms after mild traumatic brain injury (mTBI) by measuring auditory brainstem responses (ABRs) to standard click and complex speech stimuli. Consistent with reports in the literature of auditory problems after mTBI (despite normal-hearing thresholds), it was hypothesized that individuals with mTBI would have evidence of impaired neural encoding in the auditory brainstem compared to noninjured controls, as evidenced by delayed latencies and reduced amplitudes of ABR components. We further hypothesized that the speech-evoked ABR would be more sensitive than the click-evoked ABR to group differences because of its complex nature, particularly when recorded in a background noise condition. Click- and speech-ABRs were collected in 32 individuals diagnosed with mTBI in the past 3 to 18 months. All mTBI participants were experiencing ongoing injury symptoms for which they were seeking rehabilitation through a brain injury rehabilitation management program. The same data were collected in a group of 32 age- and gender-matched controls with no history of head injury. ABRs were recorded in both left and right ears for all participants in all conditions. Speech-ABRs were collected in both quiet and in a background of continuous 20-talker babble ipsilateral noise. Peak latencies and amplitudes were compared between groups and across subgroups of mTBI participants categorized by their behavioral auditory test performance. Click-ABR results were not significantly different between the mTBI and control groups. However, when comparing the control group to only those mTBI subjects with measurably decreased performance on auditory behavioral tests, small differences emerged, including delayed latencies for waves I, III, and V. Similarly, few significant group differences were observed for peak amplitudes and latencies of the speech-ABR when comparing at the whole group level

  18. Brainstem auditory evoked responses in man. 1: Effect of stimulus rise-fall time and duration

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    Hecox, K.; Squires, N.; Galambos, R.

    1975-01-01

    Short latency (under 10 msec) responses elicited by bursts of white noise were recorded from the scalps of human subjects. Response alterations produced by changes in the noise burst duration (on-time), inter-burst interval (off-time), and onset and offset shapes were analyzed. The latency of the most prominent response component, wave V, was markedly delayed with increases in stimulus rise time but was unaffected by changes in fall time. Increases in stimulus duration, and therefore in loudness, resulted in a systematic increase in latency. This was probably due to response recovery processes, since the effect was eliminated with increases in stimulus off-time. The amplitude of wave V was insensitive to changes in signal rise and fall times, while increasing signal on-time produced smaller amplitude responses only for sufficiently short off-times. It was concluded that wave V of the human auditory brainstem evoked response is solely an onset response.

  19. 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. ...

  20. 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.)

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

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    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.

  2. Electrically evoked auditory brainstem responses in children with sequential bilateral cochlear implants.

    NARCIS (Netherlands)

    Sparreboom, M.; Beynon, A.J.; Snik, A.F.M.; Mylanus, E.A.M.

    2010-01-01

    OBJECTIVE: To examine the effect of sequential bilateral cochlear implantation on auditory brainstem maturation and the effect of age in receiving the second implant (CI2). STUDY DESIGN: Prospective cohort study. SETTING: Tertiary academic referral center. PATIENTS: Thirty prelingually deaf

  3. A comparison of the brainstem auditory evoked response in healthy ears of unilaterally deaf dogs and bilaterally hearing dogs.

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    Plonek, M; Nicpoń, J; Kubiak, K; Wrzosek, M

    2017-03-01

    Auditory plasticity in response to unilateral deafness has been reported in various animal species. Subcortical changes occurring in unilaterally deaf young dogs using the brainstem auditory evoked response have not been evaluated yet. The aim of this study was to assess the brainstem auditory evoked response findings in dogs with unilateral hearing loss, and compare them with recordings obtained from healthy dogs. Brainstem auditory evoked responses (amplitudes and latencies of waves I, II, III, V, the V/I wave amplitude ratio, wave I-V, I-III and III-V interpeak intervals) were studied retrospectively in forty-six privately owned dogs, which were either unilaterally deaf or had bilateral hearing. The data obtained from the hearing ears in unilaterally deaf dogs were compared to values obtained from their healthy littermates. Statistically significant differences in the amplitude of wave III and the V/I wave amplitude ratio at 75 dB nHL were found between the group of unilaterally deaf puppies and the control group. The recordings of dogs with single-sided deafness were compared, and the results showed no statistically significant differences in the latencies and amplitudes of the waves between left- (AL) and right-sided (AR) deafness. The recordings of the brainstem auditory evoked response in canines with unilateral inborn deafness in this study varied compared to recordings from healthy dogs. Future studies looking into electrophysiological assessment of hearing in conjunction with imaging modalities to determine subcortical auditory plasticity and auditory lateralization in unilaterally deaf dogs are warranted.

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

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Gøtsche-Rasmussen, Kristian

    2011-01-01

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

  5. Brainstem auditory-evoked response (BAER) in client-owned pet ferrets with normal hearing.

    Science.gov (United States)

    Piazza, S; Huynh, M; Cauzinille, L

    2014-06-07

    The objective of this study was to evaluate the feasibility of brainstem auditory-evoked response (BAER) testing in pet ferrets in a clinical setting, and to describe a routine method and baseline data for normal hearing ferrets for future investigation of deafness in this species. Twenty-eight clinically normal client-owned ferrets were included. BAER measurements were recorded under general anaesthesia (isoflurane delivered by mask), from subcutaneously placed needle electrodes. A 'click' stimulus applied by insert earphone with an intensity of 90 dB sound pressure level (SPL) was used. The final BAER waveform represents an average of 500 successive responses. Morphology of the waveform was studied; amplitude and latency measures were determined and means were calculated. The BAER waveform of the normal ferret included 4 reproducible waves named I, II, III and V, as previously described in dogs and cats. Measurements of latencies are consistent with previous laboratory research using experimental ferrets. In the present study, a reliable routine protocol for clinical evaluation of the hearing function in the pet ferret was established. This procedure can be easily and safely performed in a clinical setting in ferrets as young as eight weeks of age. The prevalence of congenital deafness in ferrets is currently unknown but may be an important consideration, especially in ferrets with a white coat. BAER test is a useful screening for congenital deafness in this species. British Veterinary Association.

  6. Effects of otitis on hearing in dogs characterised by brainstem auditory evoked response testing.

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    Eger, C E; Lindsay, P

    1997-09-01

    Hearing function was measured in normal dogs and in dogs with otitis using brainstem auditory evoked response testing. Data were obtained from 86 normal ears and from 105 ears with otitis, categorised into four degrees of severity. The data were analysed to illustrate the differences between the hearing function in the normal and abnormal ears and to estimate the degree of impairment associated with differing degrees of pathology. While severe hearing loss seemed to be present in the dogs with more severe otitis, only two individuals were identified as being totally deaf in the affected ears and no dogs were identified in which the cleaning and examination processes had caused damage to hearing function. Cleaning the ear canal produced measurable improvements in hearing in several dogs, indicating the profound effect of physical obstruction of the external ear canal by debris. It is concluded that most dogs with chronic otitis externa are not totally deaf and that the hearing impairment that does occur has the characteristics of conductive hearing loss.

  7. Gender Disparities in Speech-evoked Auditory Brainstem Response in Healthy Adults.

    Science.gov (United States)

    Jalaei, Bahram; Zakaria, Mohd Normani; Mohd Azmi, Mohd Hafiz Afifi; Nik Othman, Nik Adilah; Sidek, Dinsuhaimi

    2017-04-01

    Gender disparities in speech-evoked auditory brainstem response (speech-ABR) outcomes have been reported, but the literature is limited. The present study was performed to further verify this issue and determine the influence of head size on speech-ABR results between genders. Twenty-nine healthy Malaysian subjects (14 males and 15 females) aged 19 to 30 years participated in this study. After measuring the head circumference, speech-ABR was recorded by using synthesized syllable /da/ from the right ear of each participant. Speech-ABR peaks amplitudes, peaks latencies, and composite onset measures were computed and analyzed. Significant gender disparities were noted in the transient component but not in the sustained component of speech-ABR. Statistically higher V/A amplitudes and less steeper V/A slopes were found in females. These gender differences were partially affected after controlling for the head size. Head size is not the main contributing factor for gender disparities in speech-ABR outcomes. Gender-specific normative data can be useful when recording speech-ABR for clinical purposes.

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

    Science.gov (United States)

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

    2017-10-01

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

  9. 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)

  10. Biliverdin-induced brainstem auditory evoked potential abnormalities in the jaundiced Gunn rat.

    Science.gov (United States)

    Rice, Ann C; Shapiro, Steven M

    2006-08-30

    Brainstem auditory evoked potential (BAEP) abnormalities occur in jaundiced Gunn rats given sulfadimethoxine to displace bilirubin bound to serum albumin, releasing it into the tissues. One problem with the model is that after displacement, plasma bilirubin levels drop and do not correlate with neurological dysfunction. In this report, we administered biliverdin, the immediate precursor of bilirubin, in 15- to 17-day-old Gunn rat pups to create an improved model of bilirubin-induced neurological dysfunction. Total plasma bilirubin (TB) levels were measured with a Leica bilirubinometer. Biliverdin (40 mg/kg) or phosphate-buffered saline (PBS) was administered either once and BAEPs recorded 8 h later or twice, 12 h apart, and BAEPs recorded 24 h after the initial injection. A single biliverdin injection produced a significantly decreased amplitude of BAEP wave III, 1.21+/-0.25 vs. 0.49+/-0.27 microV (control vs. biliverdin). The two-injection paradigm resulted in a significantly elevated TB (9.9+/-1.2 vs. 14.9+/-3.1 mg/dl; control vs. biliverdin), significant increases in I-II (1.15+/-0.08 vs. 1.42+/-0.09 ms) and I-III (2.17+/-0.08 vs. 2.5+/-0.13 ms) interwave intervals and a decrease in the amplitude of wave III (1.36+/-0.30 vs. 0.38+/-0.26 microV). Additionally, there were significant correlations between TB and the amplitude of wave III (r2=0.74) and TB and the I-III interwave interval (r2=0.51). In summary, biliverdin administration in jaundiced Gunn rat pups produces BAEP abnormalities consistent with those observed in the sulfadimethoxine model and human newborn hyperbilirubinemia and resulted in increased plasma bilirubin levels that correlate with the degree of neurological dysfunction.

  11. Brainstem auditory evoked response in adolescents with acoustic mycotic neuroma due to environmental exposure to toxic molds.

    Science.gov (United States)

    Anyanwu, Ebere; Campbell, Andrew W; High, William

    2002-01-01

    Indoor air contamination with toxic opportunistic molds is an emerging health risk worldwide. Some of the opportunistic molds include: Stachybotrys chartarum, Aspergillus species (A. fumigatus, A. flavus, A. niger, A. versicolor etc.), Cadosporium, Alternaria, Penicillium, Trichoderma, Fusarium graminearum etc. These molds flourish in homes that are moist and damp. Reports of floods are now evident in many parts of the world. With these global changes in climatic conditions that favor the opportunistic mode of living among these molds, some health authorities are beginning to feel concerned about the diversity and the extent to which opportunistic molds can cause adverse health effects in humans. Mycotoxicosis is the collective name for all the diseases caused by toxic molds. Frequently, we have cases of acoustic neuroma due to mycotoxicity in our Center. Mycotic neuroma probably has not been reported before and the application of brainstem auditory evoked response (BAER) techniques in acoustic mycotic neuroma have not been reported either. The aim of this study, therefore, was to report cases and measurements of acoustic mycotic neuroma in adolescents using the brainstem auditory evoked response. The patients' case history, clinical neurological and neurobehavioral questionnaires were assessed. Then, the BAERs were recorded between Cz and Ai, with a second channel, Cz-Ac. The case histories and the questionnaires were analyzed in conjunction with the outcome of the objective brainstem auditory evoked response measurements. The prevalent subjective findings in the patients were headaches, memory loss, hearing loss, lack of concentration, fatigue, sleep disturbance, facial swelling, rashes, nosebleeds, diarrhea, abdominal pains and respiratory difficulties. Objective BAER showed overall abnormalities in all the patients. Although the waveform abnormalities varied, 1-3 interpeak latencies were abnormal in all the patients. Overall results showed the presence of

  12. Association of Hemoglobin levels and Brainstem Auditory Evoked Responses in Lead-Exposed Children

    Science.gov (United States)

    Counter, S. Allen; Buchanan, Leo H.; Ortega, Fernando

    2012-01-01

    Objectives Decreased blood hemoglobin (HbB) levels and anemia have been associated with abnormal brainstem auditory evoked responses (BAER). Lead (Pb) exposure has also been associated with anemia and aberrant BAER. This study investigated the relationship between HbB level and BAER wave latency and amplitude in Pb-exposed Andean children. Design and methods Sixty-six children aged 2 to 15 years (mean age: 9.1; SD: 3.3) living in Pb-contaminated villages were screened for HbB levels, blood Pb (PbB) levels and BAER latencies and amplitudes. Results The mean HbB level observed in the study group was 11.9 g/dL (SD: 1.4; range: 8.6–14.8 g/dL). The mean HbB level corrected for altitude was 10.3 g/dL (SD: 1.4; range: 6.9–13.1 g/dL), and suggestive of anemia. The mean PbB level was 49.3 μg/dL (SD: 30.1; range: 4.4–119.1 μg/dL) and indicative of Pb poisoning. Spearman Rho correlation analyses revealed significant associations between the BAER absolute latencies and HbB level, indicating that as the HbB level decreased, the BAER wave latency increased. Children with low HbB levels (≤11 g/dL) showed significantly prolonged absolute latencies of waves I, II, III, IV and V compared to the children with normal HbB levels. Although a significant relationship between HbB and BAER waves was observed, no significant associations between PbB level and BAER parameters were found. Conclusion Low hemoglobin levels may diminish auditory sensory-neural function, and is therefore an important variable to consider when assessing BAER in children with anemia and/or Pb exposure. PMID:22735387

  13. Long-Term Evolution of Brainstem Electrical Evoked Responses to Sound after Restricted Ablation of the Auditory Cortex

    Science.gov (United States)

    Lamas, Verónica; Alvarado, Juan C.; Carro, Juan; Merchán, Miguel A.

    2013-01-01

    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. PMID:24066057

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

    Directory of Open Access Journals (Sweden)

    Verónica Lamas

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

  15. EEG and brainstem auditory evoked response potentials in adult male drug abusers with self-reported histories of aggressive behavior.

    Science.gov (United States)

    Fishbein, D H; Herning, R I; Pickworth, W B; Haertzen, C A; Hickey, J E; Jaffe, J H

    1989-10-01

    Auditory brainstem evoked response (BAER) and spontaneous electroencephalogram (EEG) were measured in 124 adult male drug abusers. We examined the relationships among psychiatric diagnoses, paper and pencil measures of aggression and hostility, and electrophysiological features. Subjects meeting criteria for antisocial personality disorder (ASP), as defined by DSM-III, were not significantly different from non-ASP subjects for either BAER or spontaneous EEG measures. The more overtly aggressive subjects had significant delays in BAER latency. Aggressive subjects also had more delta activity and less alpha activity in the spontaneous EEG, as have been observed in "psychopaths" and "criminals." Although ASP and aggression are related, these data indicate that aggressiveness may be a separate, albeit overlapping, trait. As both early aggression and a diagnosis of ASP are predictors of later drug use, the findings that only aggression was associated with EEG slowing and brainstem delays may indicate that ASP and aggression make independent contributions to vulnerability to the development of drug abuse.

  16. Assessment of brainstem auditory evoked potentials (BAEPs) in patients with acromegaly.

    Science.gov (United States)

    Pilecki, Witold; Bolanowski, Marek; Janocha, Anna; Daroszewski, Jacek; Kałuzny, Marcin; Sebzda, Tadeusz; Kałka, Dariusz; Sobieszczańska, Małgorzata

    2008-06-01

    Acromegaly is associated by various systemic complications, involving also the nervous system. Other studies revealed peripheral but not central nervous system impairment with somatosensory evoked potentials examinations in acromegaly. Aim of the present study was to assess whether brainstem transmission in acromegaly is disturbed. The study was carried out in 37 patients. The control group consisted of 47 healthy persons. In all of the subjects, peripheral transmission, reflected by peak I latency, and brainstem transmission, tested by interpeak latency I-V (IPL I-V), were examined. Peak I latency was delayed in 6 out of 37 patients (1 - bilaterally, 2 - right side, 3 - left side). The group-mean latency of peak I was 1.53 msec and 1.56 msec, for the right and left side, respectively. There were found no statistically significant differences between the right and left side, likewise in comparison with control group. In turn, as compared with the controls, IPL I-V was disturbed in 25 out of 37 patients: in most of the cases IPL I-V prolongation was observed (8 - bilateral prolongation, 11 - right side, 6 - left side). Moreover, the statistically significant difference between the brainstem sides (4.27 vs. 4.11 msec; p<0.05) was observed. In the examined patients with acromegaly, there was no peripheral disturbance in transmission, as examined by BAEPs registrations. Conversely, in nearly half of the patients with acromegaly, brainstem transmission was found to be delayed, and significant difference between responses from the both sides of the brainstem were noted.

  17. Gap prepulse inhibition and auditory brainstem evoked potentials as objective measures for tinnitus in guinea pigs.

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    Susanne eDehmel

    2012-05-01

    Full Text Available Tinnitus or ringing of the ears is a subjective phantom sensation necessitating behavioral models that objectively demonstrate the existence and quality of the tinnitus sensation. The gap detection test uses the acoustic startle response elicited by loud noise pulses and its gating or suppression by preceding sub-startling prepulses. Gaps in noise bands serve as prepulses, assuming that ongoing tinnitus masks the gap and results in impaired gap detection. This test has shown its reliability in rats, mice, and gerbils. No data exists for the guinea pig so far, although gap detection is similar across mammals and the acoustic startle response is a well-established tool in guinea pig studies of psychiatric disorders and in pharmacological studies. Here we investigated the startle behavior and prepulse inhibition (PPI of the guinea pig and showed that guinea pigs have a reliable startle response that can be suppressed by 15 ms gaps embedded in narrow noise bands preceding the startle noise pulse. After recovery of auditory brainstem response (ABR thresholds from a unilateral noise over-exposure centered at 7 kHz, guinea pigs showed diminished gap-induced reduction of the startle response in frequency bands between 8 and 18 kHz. This suggests the development of tinnitus in frequency regions that showed a temporary threshold shift (TTS after noise over-exposure. Changes in discharge rate and synchrony, two neuronal correlates of tinnitus, should be reflected in altered ABR waveforms, which would be useful to objectively detect tinnitus and its localization to auditory brainstem structures. Therefore we analyzed latencies and amplitudes of the first five ABR waves at suprathreshold sound intensities and correlated ABR abnormalities with the results of the behavioral tinnitus testing. Early ABR wave amplitudes up to N3 were increased for animals with tinnitus possibly stemming from hyperactivity and hypersynchrony underlying the tinnitus percept.

  18. Detection of binaural interaction in free-field evoked auditory brainstem responses by time-scale representations.

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    Schebsdat, Erik; Hessel, Horst; Seidler, Harald; Strauss, Daniel J

    2016-08-01

    The so called β-wave of the binaural interaction component (BIC) in auditory brainstem responses (ABR) has been shown to be an objective measure for binaural interaction (BI). This component is the arithmetical difference between the sum of the monaurally evoked ABRs and the binaurally evoked ABR. Unfortunately, these neural responses are known to be very fragile and as a result the calculated BIC. An additional issue is, that the findings of this measurement are predominantly needed in people with hearing loss who may use hearing devices like hearing aids (HA) or cochlear implants (CI), thus they are not able to use headphones (like in conventional ABR measurements) during the detection of possible BI. This is a crucial problem, because it is known that factors like the interaural time delay (ITD) between the receiving ears are responsible for solving tasks like sound source localization or sound source separation, but specially designed measurements to coordinate the fitting of HAs or CIs with respect to BI are still missing. In this paper, we introduce a new measurement setup that is able to detect BI depending on different ITDs in free-field evoked responses by using the more reliable instantaneous phase in the time-scale representation. With this pilot study we are able to demonstrate a decreasing BI with an increasing ITD using the wavelet phase synchronization stability analysis in ten normal hearing subjects.

  19. Effects of sleep deprivation on anaerobic exercise-induced changes in auditory brainstem evoked potentials.

    Science.gov (United States)

    Oztürk, Levent; Bulut, Erdoğan; Vardar, Selma Arzu; Uzun, Cem

    2007-09-01

    The present study was designed to assess how anaerobic exercise affects auditory brainstem response (ABR) parameters, and whether one night of sleep deprivation could alter these possible exercise-induced changes in ABRs. Seven healthy, audiologically normal male students (mean age 22.4 +/- 1.0 years) participated in the study. All subjects underwent anaerobic Wingate test for three times: (i) baseline, (ii) following a full-night of habitual sleep and (iii) following one night of sleep deprivation. ABR measurements were performed before and after the second and the third Wingate tests. Oral body temperatures were recorded at the beginning of all ABR measurements. The latencies of wave III and V significantly shortened by anaerobic loading performed in the day after habitual sleep (4.13 +/- 0.10 versus 4.01 +/- 0.17 ms, Pexercise latencies and altered exercise-induced changes in ABRs. The findings obtained in the present study show that acute anaerobic exercise is effective on ABR wave latencies independent from body temperature changes, and sleep deprivation has some modulatory effects on exercise-induced changes in ABR.

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

    Science.gov (United States)

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

    2009-11-15

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

  1. Can subject-specific single-fibre electrically evoked auditory brainstem response data be predicted from a model?

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    Malherbe, Tiaan K; Hanekom, Tania; Hanekom, Johan J

    2013-07-01

    This article investigates whether prediction of subject-specific physiological data is viable through an individualised computational model of a cochlear implant. Subject-specific predictions could be particularly useful to assess and quantify the peripheral factors that cause inter-subject variations in perception. The results of such model predictions could potentially be translated to clinical application through optimisation of mapping parameters for individual users, since parameters that affect perception would be reflected in the model structure and parameters. A method to create a subject-specific computational model of a guinea pig with a cochlear implant is presented. The objectives of the study are to develop a method to construct subject-specific models considering translation of the method to in vivo human models and to assess the effectiveness of subject-specific models to predict peripheral neural excitation on subject level. Neural excitation patterns predicted by the model are compared with single-fibre electrically evoked auditory brainstem responses obtained from the inferior colliculus in the same animal. Results indicate that the model can predict threshold frequency location, spatial spread of bipolar and tripolar stimulation and electrode thresholds relative to one another where electrodes are located in different cochlear structures. Absolute thresholds and spatial spread using monopolar stimulation are not predicted accurately. Improvements to the model should address this. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

  2. Effect of middle ear effusion on the brain-stem auditory evoked response of Cavalier King Charles Spaniels.

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    Harcourt-Brown, Thomas R; Parker, John E; Granger, Nicolas; Jeffery, Nick D

    2011-06-01

    Brain-stem auditory evoked responses (BAER) were assessed in 23 Cavalier King Charles Spaniels with and without middle ear effusion at sound intensities ranging from 10 to 100 dB nHL. Significant differences were found between the median BAER threshold for ears where effusions were present (60 dB nHL), compared to those without (30 dB nHL) (P=0.001). The slopes of latency-intensity functions from both groups did not differ, but the y-axis intercept when the x value was zero was greater in dogs with effusions (P=0.009), consistent with conductive hearing loss. Analysis of latency-intensity functions suggested the degree of hearing loss due to middle ear effusion was 21 dB (95% confidence between 10 and 33 dB). Waves I-V inter-wave latency at 90 dB nHL was not significantly different between the two groups. These findings demonstrate that middle ear effusion is associated with a conductive hearing loss of 10-33 dB in affected dogs despite the fact that all animals studied were considered to have normal hearing by their owners. Copyright © 2010. Published by Elsevier Ltd.

  3. A new vision on the averaging technique for the estimation of non-stationary Brainstem Auditory-Evoked Potentials: application of a metaheuristic method.

    Science.gov (United States)

    Naït-Ali, Amine; Siarry, Patrick

    2006-06-01

    The aim of this paper consists in highlighting the use of the averaging technique in some biomedical applications, such as evoked potentials (EP) extraction. We show that this technique, which is generally considered as classical, can be very efficient if the dynamic model of the signal to be estimated is a priori known. Therefore, using an appropriate model and under some specific conditions, one can show that the estimation can be performed efficiently even in case of a very low signal to noise ratio (SNR), which occurs when handling Brainstem Auditory-Evoked Potentials.

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

    Science.gov (United States)

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

    2013-01-01

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

  5. Auditory assessment of children with severe hearing loss using behavioural observation audiometry and brainstem evoked response audiometry

    OpenAIRE

    Rakhi Kumari; Priyanko Chakraborty; Jain, R K; Dhananjay Kumar

    2016-01-01

    Background: Early detection of hearing loss has been a long-standing priority in the field of audiology. Currently available auditory testing methods include both behavioural and non-behavioural or objective tests of hearing. This study was planned with an objective to assess hearing loss in children using behavioural observation audiometry and brain stem evoked response audiometry. Methods: A total of 105 cases suffering from severe to profound hearing loss were registered. After proper h...

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

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    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.

  7. Presbycusis and auditory brainstem responses: a review

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    Shilpa Khullar

    2011-06-01

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

  8. Using click-evoked auditory brainstem response thresholds in infants to estimate the corresponding pure-tone audiometry thresholds in children referred from UNHS.

    Science.gov (United States)

    Lu, Tsun-Min; Wu, Fang-Wei; Chang, Hsiuwen; Lin, Hung-Ching

    2017-04-01

    To examine whether behavioral pure-tone audiometry (PTA) thresholds in children can be accurately estimated from the corresponding infants' click-evoked auditory brainstem response (ABR) thresholds through a retrospective review of data from a universal newborn hearing screening (UNHS) program in Taiwan. According to medical records from Mackay Memorial Hospital, Taipei Hospital District, 45,450 newborns received hearing screening during January 1999-December 2011. Among these newborns, 104 (82, both ears; 22, one ear; total, 186 ears) received regular follow-up and were recruited as subjects. The relationship between infant click-evoked ABR thresholds and the corresponding child PTA thresholds was determined through Pearson correlation coefficient and linear regression analyses. The correlation coefficient between click-evoked ABR thresholds and behavioral PTA thresholds at the average of frequencies of 1-4 and 2-4 kHz was 0.76 and 0.76, respectively. Linear regression analysis showed that behavioral audiometry thresholds at the average of frequencies of 1-4 and 2-4 kHz were accurately estimated from click-evoked ABR thresholds in 57% and 58% children, respectively. Click-evoked ABR testing is a reliable tool to cautiously estimate behavioral PTA thresholds at the average of frequencies of 1-4 and 2-4 kHz. For accurately performing hearing aid fitting and auditory rehabilitation in congenitally deaf infants, a combination of frequency-specific tone-burst ABR and click-evoked ABR should be used. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Rhesus macaque model of chronic opiate dependence and neuro-AIDS: longitudinal assessment of auditory brainstem responses and visual evoked potentials.

    Science.gov (United States)

    Riazi, Mariam; Marcario, Joanne K; Samson, Frank K; Kenjale, Himanshu; Adany, Istvan; Staggs, Vincent; Ledford, Emily; Marquis, Janet; Narayan, Opendra; Cheney, Paul D

    2009-06-01

    Our work characterizes the effects of opiate (morphine) dependence on auditory brainstem and visual evoked responses in a rhesus macaque model of neuro-AIDS utilizing a chronic continuous drug delivery paradigm. The goal of this study was to clarify whether morphine is protective, or if it exacerbates simian immunodeficiency virus (SIV)-related systemic and neurological disease. Our model employs a macrophage tropic CD4/CCR5 coreceptor virus, SIV(mac)239 (R71/E17), which crosses the blood-brain barrier shortly after inoculation and closely mimics the natural disease course of human immunodeficiency virus infection. The cohort was divided into three groups: morphine only, SIV only, and SIV + morphine. Evoked potential (EP) abnormalities in subclinically infected macaques were evident as early as 8 weeks postinoculation. Prolongations in EP latencies were observed in SIV-infected macaques across all modalities. Animals with the highest cerebrospinal fluid viral loads and clinical disease showed more abnormalities than those with subclinical disease, confirming our previous work (Raymond et al., J Neurovirol 4:512-520, 1998; J Neurovirol 5:217-231, 1999; AIDS Res Hum Retroviruses 16:1163-1173, 2000). Although some differences were observed in auditory and visual evoked potentials in morphine-treated compared to morphine-untreated SIV-infected animals, the effects were relatively small and not consistent across evoked potential type. However, morphine-treated animals with subclinical disease had a clear tendency toward higher virus loads in peripheral and central nervous system tissues (Marcario et al., J Neuroimmune Pharmacol 3:12-25, 2008) suggesting that if had been possible to follow all animals to end-stage disease, a clearer pattern of evoked potential abnormality might have emerged.

  10. Identification of Dynamic Patterns of Speech-Evoked Auditory Brainstem Response Based on Ensemble Empirical Mode Decomposition and Nonlinear Time Series Analysis Methods

    Science.gov (United States)

    Mozaffarilegha, Marjan; Esteki, Ali; Ahadi, Mohsen; Nazeri, Ahmadreza

    The speech-evoked auditory brainstem response (sABR) shows how complex sounds such as speech and music are processed in the auditory system. Speech-ABR could be used to evaluate particular impairments and improvements in auditory processing system. Many researchers used linear approaches for characterizing different components of sABR signal, whereas nonlinear techniques are not applied so commonly. The primary aim of the present study is to examine the underlying dynamics of normal sABR signals. The secondary goal is to evaluate whether some chaotic features exist in this signal. We have presented a methodology for determining various components of sABR signals, by performing Ensemble Empirical Mode Decomposition (EEMD) to get the intrinsic mode functions (IMFs). Then, composite multiscale entropy (CMSE), the largest Lyapunov exponent (LLE) and deterministic nonlinear prediction are computed for each extracted IMF. EEMD decomposes sABR signal into five modes and a residue. The CMSE results of sABR signals obtained from 40 healthy people showed that 1st, and 2nd IMFs were similar to the white noise, IMF-3 with synthetic chaotic time series and 4th, and 5th IMFs with sine waveform. LLE analysis showed positive values for 3rd IMFs. Moreover, 1st, and 2nd IMFs showed overlaps with surrogate data and 3rd, 4th and 5th IMFs showed no overlap with corresponding surrogate data. Results showed the presence of noisy, chaotic and deterministic components in the signal which respectively corresponded to 1st, and 2nd IMFs, IMF-3, and 4th and 5th IMFs. While these findings provide supportive evidence of the chaos conjecture for the 3rd IMF, they do not confirm any such claims. However, they provide a first step towards an understanding of nonlinear behavior of auditory system dynamics in brainstem level.

  11. Brainstem Auditory Evoked Potentials for diagnosing Autism Spectrum Disorder, ADHD and Schizophrenia Spectrum Disorders in adults. A blinded study.

    Science.gov (United States)

    Manouilenko, Irina; Humble, Mats B; Georgieva, Jeanette; Bejerot, Susanne

    2017-11-01

    The aim of the present study was to examine the clinical utility of complex auditory brainstem response (c-ABR) and investigate if c-ABR is helpful in the diagnostic procedure. Thirty-one adult psychiatric patients, thoroughly diagnosed with autism spectrum disorder (ASD) (n=16), ADHD (n=8), or schizophrenia spectrum disorder (SSD) (n=7) and 15 healthy controls (HC), were blindly assessed with SensoDetect BERA. This c-ABR correctly identified psychiatric diagnoses in 4 patients (13%) and provided partially correct diagnoses in 11 more patients. Of the 15 HC, 6 were misclassified as psychiatric patients. The Cohen´s kappa coefficient (κ) was substantial for HC (κ=0.67), fair for SSD (κ=0.37), slight for ADHD (κ=0.09) and without agreement in ASD (κ=-0.03). In conclusion, we found the c-ABR method unhelpful and unreliable as a tool in clinical diagnostics. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Auditory brainstem implant program development.

    Science.gov (United States)

    Schwartz, Marc S; Wilkinson, Eric P

    2017-08-01

    Auditory brainstem implants (ABIs), which have previously been used to restore auditory perception to deaf patients with neurofibromatosis type 2 (NF2), are now being utilized in other situations, including treatment of congenitally deaf children with cochlear malformations or cochlear nerve deficiencies. Concurrent with this expansion of indications, the number of centers placing and expressing interest in placing ABIs has proliferated. Because ABI placement involves posterior fossa craniotomy in order to access the site of implantation on the cochlear nucleus complex of the brainstem and is not without significant risk, we aim to highlight issues important in developing and maintaining successful ABI programs that would be in the best interests of patients. Especially with pediatric patients, the ultimate benefits of implantation will be known only after years of growth and development. These benefits have yet to be fully elucidated and continue to be an area of controversy. The limited number of publications in this area were reviewed. Review of the current literature was performed. Disease processes, risk/benefit analyses, degrees of evidence, and U.S. Food and Drug Administration approvals differ among various categories of patients in whom auditory brainstem implantation could be considered for use. We suggest sets of criteria necessary for the development of successful and sustaining ABI programs, including programs for NF2 patients, postlingually deafened adult nonneurofibromatosis type 2 patients, and congenitally deaf pediatric patients. Laryngoscope, 127:1909-1915, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  13. Evaluation of the occurrence of canine congenital sensorineural deafness in puppies of predisposed dog breeds using the brainstem auditory evoked response.

    Science.gov (United States)

    Płonek, Marta; Giza, Elżbieta; Niedźwiedź, Artur; Kubiak, Krzysztof; Nicpoń, Józef; Wrzosek, Marcin

    2016-12-01

    Canine congenital sensorineural deafness (CCSD) affects predisposed breeds of dogs and is primarily caused by an atrophy of the stria vascularis of the organ of Corti. The analysis of the brainstem auditory evoked response (BAER) is a reliable method for the evaluation of hearing in animals as it allows an accurate detection of unilateral or bilateral deafness. The occurrence of unilateral and bilateral deafness using the BAER was determined in a representative group of dogs in Poland, including Bull Terriers (n = 117), Australian Cattle Dogs (n = 62), English Setters (n = 32) and the Dogo Argentino (n = 32). Overall deafness, deafness in each dog breed and an association between deafness and phenotype were studied. Among the 243 dogs tested, 156 (81%) had a normal BAER, 27 (11%) were unilaterally deaf, and 12 (5%) were bilaterally deaf. The amplitudes and latencies of waves I, II, III, V, the V/I wave amplitude ratio, and wave I-V, I-III and III-V inter-peak intervals were recorded for each dog. Unilaterally and bilaterally deaf dogs were present in all the dog breeds studied. There were 17 (14.5%) deaf Bull Terriers, three (4.8%) deaf Australian Cattle Dogs, seven (21.9%) deaf English Setters, and 12 (37.5%) deaf Dogos Argentinos. Preventive BAER screening should be routinely performed in these four breeds to prevent the spread of genes responsible for deafness.

  14. Rapid Increase in Neural Conduction Time in the Adult Human Auditory Brainstem Following Sudden Unilateral Deafness

    National Research Council Canada - National Science Library

    Maslin, M R. D; Lloyd, S K; Rutherford, S; Freeman, S; King, A; Moore, D R; Munro, K J

    2015-01-01

    .... Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma...

  15. Glial cell contributions to auditory brainstem development

    Directory of Open Access Journals (Sweden)

    Karina S Cramer

    2016-10-01

    Full Text Available Glial cells, previously thought to have generally supporting roles in the central nervous system, are emerging as essential contributors to multiple aspects of neuronal circuit function and development. This review focuses on the contributions of glial cells to the development of specialized auditory pathways in the brainstem. These pathways display specialized synapses and an unusually high degree of precision in circuitry that enables sound source localization. The development of these pathways thus requires highly coordinated molecular and cellular mechanisms. Several classes of glial cells, including astrocytes, oligodendrocytes, and microglia, have now been explored in these circuits in both avian and mammalian brainstems. Distinct populations of astrocytes are found over the course of auditory brainstem maturation. Early appearing astrocytes are associated with spatial compartments in the avian auditory brainstem. Factors from late appearing astrocytes promote synaptogenesis and dendritic maturation, and astrocytes remain integral parts of specialized auditory synapses. Oligodendrocytes play a unique role in both birds and mammals in highly regulated myelination essential for proper timing to decipher interaural cues. Microglia arise early in brainstem development and may contribute to maturation of auditory pathways. Together these studies demonstrate the importance of non-neuronal cells in the assembly of specialized auditory brainstem circuits.

  16. Auditory brain-stem responses in adrenomyeloneuropathy.

    Science.gov (United States)

    Grimes, A M; Elks, M L; Grunberger, G; Pikus, A M

    1983-09-01

    We studied three patients with adrenomyeloneuropathy. Complete audiologic assessment was obtained: two patients showed unimpaired peripheral hearing and one showed a mild high-frequency hearing loss. Auditory brain-stem responses were abnormal in both ears of all subjects, with one subject showing no response above wave I, and the other two having significant wave I to III and wave III to V interval prolongations. We concluded that auditory brain-stem response testing provides a simple, valid, reliable method for demonstrating neurologic abnormality in adrenomyeloneuropathy even prior to evidence of clinical signs.

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

    Science.gov (United States)

    Maddox, Ross K; Lee, Adrian K C

    2018-01-01

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

  18. Albumin administration protects against bilirubin-induced auditory brainstem dysfunction in Gunn rat pups

    NARCIS (Netherlands)

    Schreuder, Andrea B.; Rice, Ann C.; Vanikova, Jana; Vitek, Libor; Shapiro, Steven M.; Verkade, Henkjan J.

    2013-01-01

    Background Free bilirubin (Bf), the unbound fraction of unconjugated bilirubin (UCB), can induce neurotoxicity, including impairment of the auditory system, which can be assessed by brainstem auditory evoked potentials (BAEPs). We hypothesized that albumin might reduce the risk of neurotoxicity by

  19. Effects of Caffeine on Auditory Brainstem Response

    Directory of Open Access Journals (Sweden)

    Saleheh Soleimanian

    2008-06-01

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

  20. The auditory brainstem is a barometer of rapid auditory learning.

    Science.gov (United States)

    Skoe, E; Krizman, J; Spitzer, E; Kraus, N

    2013-07-23

    To capture patterns in the environment, neurons in the auditory brainstem rapidly alter their firing based on the statistical properties of the soundscape. How this neural sensitivity relates to behavior is unclear. We tackled this question by combining neural and behavioral measures of statistical learning, a general-purpose learning mechanism governing many complex behaviors including language acquisition. We recorded complex auditory brainstem responses (cABRs) while human adults implicitly learned to segment patterns embedded in an uninterrupted sound sequence based on their statistical characteristics. The brainstem's sensitivity to statistical structure was measured as the change in the cABR between a patterned and a pseudo-randomized sequence composed from the same set of sounds but differing in their sound-to-sound probabilities. Using this methodology, we provide the first demonstration that behavioral-indices of rapid learning relate to individual differences in brainstem physiology. We found that neural sensitivity to statistical structure manifested along a continuum, from adaptation to enhancement, where cABR enhancement (patterned>pseudo-random) tracked with greater rapid statistical learning than adaptation. Short- and long-term auditory experiences (days to years) are known to promote brainstem plasticity and here we provide a conceptual advance by showing that the brainstem is also integral to rapid learning occurring over minutes. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Construction of Hindi Speech Stimuli for Eliciting Auditory Brainstem Responses.

    Science.gov (United States)

    Ansari, Mohammad Shamim; Rangasayee, R

    2016-12-01

    Speech-evoked auditory brainstem responses (spABRs) provide considerable information of clinical relevance to describe auditory processing of complex stimuli at the sub cortical level. The substantial research data have suggested faithful representation of temporal and spectral characteristics of speech sounds. However, the spABR are known to be affected by acoustic properties of speech, language experiences and training. Hence, there exists indecisive literature with regards to brainstem speech processing. This warrants establishment of language specific speech stimulus to describe the brainstem processing in specific oral language user. The objective of current study is to develop Hindi speech stimuli for recording auditory brainstem responses. The Hindi stop speech of 40 ms containing five formants was constructed. Brainstem evoked responses to speech sound |da| were gained from 25 normal hearing (NH) adults having mean age of 20.9 years (SD = 2.7) in the age range of 18-25 years and ten subjects (HI) with mild SNHL of mean 21.3 years (SD = 3.2) in the age range of 18-25 years. The statistically significant differences in the mean identification scores of synthesized for speech stimuli |da| and |ga| between NH and HI were obtained. The mean, median, standard deviation, minimum, maximum and 95 % confidence interval for the discrete peaks and V-A complex values of electrophysiological responses to speech stimulus were measured and compared between NH and HI population. This paper delineates a comprehensive methodological approach for development of Hindi speech stimuli and recording of ABR to speech. The acoustic characteristic of stimulus |da| was faithfully represented at brainstem level in normal hearing adults. There was statistically significance difference between NH and HI individuals. This suggests that spABR offers an opportunity to segregate normal speech encoding from abnormal speech processing at sub cortical level, which implies that

  2. Functional abnormality of the auditory brainstem in high-risk late preterm infants.

    Science.gov (United States)

    Jiang, Ze D; Ping, Li L; Wilkinson, Andrew R

    2012-05-01

    To examine whether late preterm infants with perinatal problems are at risk of brainstem auditory impairment. 68 high-risk late preterm infants (gestation 33-36 weeks) with perinatal problems or conditions were studied at term using maximum length sequence brainstem auditory evoked response. The controls were 41 normal term infants and 37 low-risk late preterm infants. Compared with normal term infants, the high-risk late preterm infants demonstrated a significant abnormal increase in MLS BAER variables that mainly reflect more central function of the brainstem auditory pathway, including wave V latency, III-V and I-V interpeak intervals, and III-V/I-III interval ratio. The abnormalities were more significant at higher than at lower click rates. The slopes of MLS BAER-rate function for these variables were increased. Compared with low-risk late preterm infants, the high-risk infants showed similar, though slightly less significant, abnormalities, mainly a significant increase in III-V and I-V intervals. Maximum length sequence brainstem auditory evoked response components that mainly reflect central function of the auditory brainstem were abnormal at term in high-risk late preterm infants. More central regions of the auditory brainstem are impaired in high-risk late preterm infants, which is mainly caused by associated perinatal problems or conditions. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  3. Neurodynamics, tonality, and the auditory brainstem response.

    Science.gov (United States)

    Large, Edward W; Almonte, Felix V

    2012-04-01

    Tonal relationships are foundational in music, providing the basis upon which musical structures, such as melodies, are constructed and perceived. A recent dynamic theory of musical tonality predicts that networks of auditory neurons resonate nonlinearly to musical stimuli. Nonlinear resonance leads to stability and attraction relationships among neural frequencies, and these neural dynamics give rise to the perception of relationships among tones that we collectively refer to as tonal cognition. Because this model describes the dynamics of neural populations, it makes specific predictions about human auditory neurophysiology. Here, we show how predictions about the auditory brainstem response (ABR) are derived from the model. To illustrate, we derive a prediction about population responses to musical intervals that has been observed in the human brainstem. Our modeled ABR shows qualitative agreement with important features of the human ABR. This provides a source of evidence that fundamental principles of auditory neurodynamics might underlie the perception of tonal relationships, and forces reevaluation of the role of learning and enculturation in tonal cognition. © 2012 New York Academy of Sciences.

  4. Human auditory evoked potentials. I - Evaluation of components

    Science.gov (United States)

    Picton, T. W.; Hillyard, S. A.; Krausz, H. I.; Galambos, R.

    1974-01-01

    Fifteen distinct components can be identified in the scalp recorded average evoked potential to an abrupt auditory stimulus. The early components occurring in the first 8 msec after a stimulus represent the activation of the cochlea and the auditory nuclei of the brainstem. The middle latency components occurring between 8 and 50 msec after the stimulus probably represent activation of both auditory thalamus and cortex but can be seriously contaminated by concurrent scalp muscle reflex potentials. The longer latency components occurring between 50 and 300 msec after the stimulus are maximally recorded over fronto-central scalp regions and seem to represent widespread activation of frontal cortex.

  5. Brainstem auditory evoked potential, visual evoked potential and nerve conduction velocity and their relation with HbA1c and beta 2 microglobulin in children with insulin dependent diabetes mellitus.

    Science.gov (United States)

    Akinci, A; Deda, G; Karagöl, U; Teziç, T

    1994-01-01

    Brain stem auditory evoked response (BAER), visual evoked response (VER) and nerve conduction velocities (NCV) were studied in 18 insulin-dependent diabetic children between the ages of 3.5 and 16 years (mean 9.0 +/- 3.2 years). The results were compared with those of age-matched controls. The VER latencies of the diabetic children in the right eye and left eye were significantly prolonged when compared with the control group. NCV of n. peroneus and the latency of sensorial n. medianus were significantly impaired when compared with the control group. Although the latencies of waves III, IV and V of the right ear and the interpeak latencies of I-III, I-V, III-V of both ears were prolonged, the comparison with the control group was not significant. The beta 2 microglobulin levels of the diabetic patients were significantly higher than those of the control group. There was a positive correlation between the beta 2 microglobulin and the BAER interpeak latencies of wave III-V in both ears (r: 0.51 p sensorial) with beta 2 microglobulin (r: 0.52 p eyes separately. In our study the prolonged latencies of VER and BAER were detected in the absence of clinical abnormalities in visual and hearing systems.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Speech Auditory Brainstem Response through hearing aid stimulation.

    Science.gov (United States)

    Bellier, Ludovic; Veuillet, Evelyne; Vesson, Jean-François; Bouchet, Patrick; Caclin, Anne; Thai-Van, Hung

    2015-07-01

    Millions of people across the world are hearing impaired, and rely on hearing aids to improve their everyday life. Objective audiometry could optimize hearing aid fitting, and is of particular interest for non-communicative patients. Speech Auditory Brainstem Response (speech ABR), a fine electrophysiological marker of speech encoding, is presently seen as a promising candidate for implementing objective audiometry; yet, unlike lower-frequency auditory-evoked potentials (AEPs) such as cortical AEPs or auditory steady-state responses (ASSRs), aided-speech ABRs (i.e., speech ABRs through hearing aid stimulation) have almost never been recorded. This may be due to their high-frequency components requesting a high temporal precision of the stimulation. We assess here a new approach to record high-quality and artifact-free speech ABR while stimulating directly through hearing aids. In 4 normal-hearing adults, we recorded speech ABR evoked by a /ba/ syllable binaurally delivered through insert earphones for quality control or through hearing aids. To assess the presence of a potential stimulus artifact, recordings were also done in mute conditions with the exact same potential sources of stimulus artifacts as in the main runs. Hearing aid stimulation led to artifact-free speech ABR in each participant, with the same quality as when using insert earphones, as shown with signal-to-noise (SNR) measurements. Our new approach consisting in directly transmitting speech stimuli through hearing aids allowed for a perfect temporal precision mandatory in speech ABR recordings, and could thus constitute a decisive step in hearing impairment investigation and in hearing aid fitting improvement. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Auditory brainstem responses in term newborns with hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Mônica Jubran Chapchap

    2006-09-01

    Full Text Available Objective: To evaluate auditory brainstem responses in term newbornswith hyperbilirubinemia. Methods: Seventy-one newborns, 35 withaggravated physiological neonatal jaundice (group I, 24 with ABOblood incompatibility (group II and 12 not suffering from jaundice orany other disease were submitted to auditory brainstem responses.Statistical analysis of variance was performed to evaluate waveformreproducibility, absolute and interwave latencies, and Pearsoncoefficient was used to evaluate the association between the level ofserum bilirubin and abnormalities in the auditory brainstem responses.Results: According to the criteria assumed in the present paperwaveform alterations were more frequently found in group II than inthe control group (p = 0.023. No significant differences were observedbetween groups I and II (p = 0.083 or between control group andgroup I (p = 0.166. Wave I latency at 80 dBHL for good reproducibilityresponses and III-V interwave latency at 40 dBHL for poor reproducibilityresponses of newborns with hyperbilirubinemia showed significantfindings in relation to the control group (0.008 and 0.004 respectively.There was positive, weak (9% association between serum indirectbilirubin levels and auditory brainstem responses only when the twogroups were analyzed together. Conclusions: Neonatalhyperbilirubinemia changed the conduction of auditory stimulus interm newborns with jaundice caused by ABO blood incompatibility.There was poor positive association between plasma levels of bilirubinand abnormalities in auditory brainstem responses.

  8. Frequency-specific objective audiometry: tone-evoked brainstem responses and steady-state responses to 40 Hz and 90 Hz amplitude modulated stimuli.

    NARCIS (Netherlands)

    Reijden, C.S. van der; Mens, L.H.M.; Snik, A.F.M.

    2006-01-01

    Tone-evoked Auditory Brainstem Responses (tone-burst ABRs) and Auditory Steady-State Responses (ASSRs) with 40 or 90 Hz amplitude modulation (AM) were compared, using the same equipment and recording parameters, to determine which of these three methods most accurately approached the behavioural

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

    Science.gov (United States)

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

    2017-04-01

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

  10. Objective information-theoretic algorithm for detecting brainstem-evoked responses to complex stimuli.

    Science.gov (United States)

    Bidelman, Gavin M

    2014-09-01

    The scalp-recorded frequency-following response (FFR), an auditory-evoked potential with putative neural generators in the rostral brainstem, provides a robust representation of the neurophysiologic encoding of complex stimuli. The FFR is rapidly becoming a valuable tool for understanding the neural transcription of speech and music, language-related processing disorders, and brain plasticity at initial stages of the auditory pathway. Despite its potential clinical and empirical utility, determining the presence of a response is still dependent on the subjective interpretation by an experimenter/clinician. The purpose of the present work was to develop and validate a fully objective procedure for the automatic detection of FFRs elicited by complex auditory stimuli, including speech. Mutual information (MI) was computed between the spectrographic representation of neural FFRs and their evoking acoustic stimuli to quantify the amount of shared time-frequency information between electrophysiologic responses and stimulus acoustics. To remove human subjectivity associated with typical response evaluation, FFRs were first simulated at known signal-to-noise ratios using a computational model of the auditory periphery. The MI at which model FFRs contained +3 dB Signal-to-noise ratio was taken as the criterion threshold (θMI) for the presence of a response. θMI was then applied as a binary classifier on actual neurophysiologic responses recorded previously in human participants (n = 35). Sham recordings, in which no stimulus was presented to participants, allowed us to determine the receiver operating characteristics of the MI metric and the capabilities of the algorithm to segregate true evoked responses from sham recordings. RESULTS showed high overall accuracy (93%) in the metric's ability to identify true responses from sham recordings. The metric's overall performance was considerably better than trained human observers who, on average, accurately identified only

  11. Classification of Auditory Evoked Potentials based on the wavelet decomposition and SVM network

    Directory of Open Access Journals (Sweden)

    Michał Suchocki

    2015-12-01

    Full Text Available For electrophysiological hearing assessment and diagnosis of brain stem lesions, the most often used are auditory brainstem evoked potentials of short latency. They are characterized by successively arranged maxima as a function of time, called waves. Morphology of the course, in particular, the timing and amplitude of each wave, allow a neurologist to make diagnose, what is not an easy task. A neurologist should be experienced, concentrated, and should have very good perception. In order to support his diagnostic process, the authors have developed an algorithm implementing the automated classification of auditory evoked potentials to the group of pathological and physiological cases, the sensitivity and specificity determined for an independent test group (of 50 cases of respectively 84% and 88%.[b]Keywords[/b]: biomedical engineering, brainstem auditory evoked potentials, wavelet decomposition, support vector machine

  12. Relationship between brainstem auditory function during the neonatal period and depressed Apgar score.

    Science.gov (United States)

    Jiang, Ze Dong; Wilkinson, Andrew Robert

    2010-09-01

    To understand whether infants with depressed Apgar scores are at high risk of brainstem auditory impairment, we examined the relationship between brainstem auditory function during the neonatal period and depressed Apgar score. Brainstem auditory evoked responses (BAERs) were recorded from day 1 to day 30 in 145 term infants with Apgar scores Apgar score none of BAER response wave latencies and interpeak intervals during the first 15 days correlated significantly with the score. On day 30, all wave latencies but no intervals correlated negatively with the score (all p Apgar score, only on day 3 wave V latency and I-V and III-V intervals correlated negatively with the score (all p Apgar score, only III-V interval correlated negatively with the score (p Apgar scores. Wave V latency and I-V and III-V intervals on day 3 were all significantly longer in infants with 5-min Apgar scores 6. During the neonatal period, only on day 3 after birth a depressed 5-min Apgar score is an indicator associated with central auditory impairment. A depressed 1-min score may be associated with later peripheral auditory impairment.

  13. Binaural interaction in the auditory brainstem response: a normative study.

    Science.gov (United States)

    Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Battmer, Rolf-Dieter; Dhooge, Ingeborg J M

    2015-04-01

    Binaural interaction can be investigated using auditory evoked potentials. A binaural interaction component can be derived from the auditory brainstem response (ABR-BIC) and is considered evidence for binaural interaction at the level of the brainstem. Although click ABR-BIC has been investigated thoroughly, data on 500 Hz tone-burst (TB) ABR-BICs are scarce. In this study, characteristics of click and 500 Hz TB ABR-BICs are described. Furthermore, reliability of both click and 500 Hz TB ABR-BIC are investigated. Eighteen normal hearing young adults (eight women, ten men) were included. ABRs were recorded in response to clicks and 500 Hz TBs. ABR-BICs were derived by subtracting the binaural response from the sum of the monaural responses measured in opposite ears. Good inter-rater reliability is obtained for both click and 500 Hz TB ABR-BICs. The most reliable peak in click ABR-BIC occurs at a mean latency of 6.06 ms (SD 0.354 ms). Reliable 500 Hz TB ABR-BIC are obtained with a mean latency of 9.47 ms (SD 0.678 ms). Amplitudes are larger for 500 Hz TB ABR-BIC than for clicks. The most reliable peak in click ABR-BIC occurs at the downslope of wave V. Five hundred Hertz TB ABR-BIC is characterized by a broad positivity occurring at the level of wave V. The ABR-BIC is a useful technique to investigate binaural interaction in certain populations. Examples are bilateral hearing aid users, bilateral cochlear implant users and bimodal listeners. The latter refers to the combination of unilateral cochlear implantation and contralateral residual hearing. The majority of these patients have residual hearing in the low frequencies. The current study suggests that 500 Hz TB ABR-BIC may be a suitable technique to assess binaural interaction in this specific population of cochlear implant users. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2009-01-01

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

  15. Long Latency Auditory Evoked Potentials during Meditation.

    Science.gov (United States)

    Telles, Shirley; Deepeshwar, Singh; Naveen, Kalkuni Visweswaraiah; Pailoor, Subramanya

    2015-10-01

    The auditory sensory pathway has been studied in meditators, using midlatency and short latency auditory evoked potentials. The present study evaluated long latency auditory evoked potentials (LLAEPs) during meditation. Sixty male participants, aged between 18 and 31 years (group mean±SD, 20.5±3.8 years), were assessed in 4 mental states based on descriptions in the traditional texts. They were (a) random thinking, (b) nonmeditative focusing, (c) meditative focusing, and (d) meditation. The order of the sessions was randomly assigned. The LLAEP components studied were P1 (40-60 ms), N1 (75-115 ms), P2 (120-180 ms), and N2 (180-280 ms). For each component, the peak amplitude and peak latency were measured from the prestimulus baseline. There was significant decrease in the peak latency of the P2 component during and after meditation (Pmeditation facilitates the processing of information in the auditory association cortex, whereas the number of neurons recruited was smaller in random thinking and non-meditative focused thinking, at the level of the secondary auditory cortex, auditory association cortex and anterior cingulate cortex. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  16. Auditory-evoked potentials during coma: do they improve our prediction of awakening in comatose patients?

    Science.gov (United States)

    Rodriguez, Rosendo A; Bussière, Miguel; Froeschl, Michael; Nathan, Howard J

    2014-02-01

    The mismatch negativity (MMN), an auditory event-related potential, has been identified as a good indicator of recovery of consciousness during coma. We explored the predictive value of the MMN and other auditory-evoked potentials including brainstem and middle-latency potentials for predicting awakening in comatose patients after cardiac arrest or cardiogenic shock. Auditory brainstem, middle-latency (Pa wave), and event-related potentials (N100 and MMN waves) were recorded in 17 comatose patients and 9 surgical patients matched by age and coronary artery disease. Comatose patients were followed up daily to determine recovery of consciousness and classified as awakened and nonawakened. Among the auditory-evoked potentials, the presence or absence of MMN best discriminated between patients who awakened or those who did not. Mismatch negativity was present during coma in all patients who awakened (7/7) and in 2 of those (2/10) who did not awaken. In patients who awakened and in whom MMN was detected, 3 of those awakened between 2 and 3 days and 4 between 9 and 21 days after evoked potential examination. All awakened patients had intact N100 waves and identifiable brainstem and middle-latency waves. In nonawakened patients, N100 and Pa waves were detected in 5 cases (50%) and brainstem waves in 9 (90%). The MMN is a good predictor of awakening in comatose patients after cardiac arrest and cardiogenic shock and can be measured days before awakening encouraging ongoing life support. © 2013.

  17. DEVELOPING ‘STANDARD NOVEL ‘VAD’ TECHNIQUE’ AND ‘NOISE FREE SIGNALS’ FOR SPEECH AUDITORY BRAINSTEM RESPONSES FOR HUMAN SUBJECTS

    OpenAIRE

    Ranganadh Narayanam

    2016-01-01

    In this research as a first step we have concentrated on collecting non-intra cortical EEG data of Brainstem Speech Evoked Potentials from human subjects in an Audiology Lab in University of Ottawa. The problems we have considered are the most advanced and most essential problems of interest in Auditory Neural Signal Processing area in the world: The first problem is the Voice Activity Detection (VAD) in Speech Auditory Brainstem Responses (ABR); The second problem is to identify the best De-...

  18. Auditory brainstem response recording to multiple interleaved broadband chirps.

    Science.gov (United States)

    Cebulla, Mario; Stürzebecher, Ekkehard; Don, Manuel; Müller-Mazzotta, Jochen

    2012-01-01

    The simultaneous application of multiple stimuli that excite different frequency regions of the cochlea is a well-established method for recording frequency-specific auditory steady state responses. Because the stimuli are applied at different repetition rates, they actually do not appear exactly simultaneously. There is always a certain time difference between the multiple frequency-specific stimuli. This is true also for multiple interleaved broadband stimuli. Therefore, because of this time difference, one may expect a successful recording of responses to multiple broadband chirp stimuli even when such stimuli activate the whole cochlear partition. This article describes a technique for recording auditory brainstem responses evoked by trains of broadband chirps presented simultaneously at equal stimulus levels but at different repetition rates. The interactions between the interleaved stimulus trains were studied to lay the foundation for a rapid method of assessing temporal aspects of peripheral auditory processing. The first step in laying this foundation is to determine the characteristics of responses from an intact and normal-hearing system to these interleaved chirp trains. Subsequently, the studied interactions between the interleaved applied stimuli may provide a referential framework for future clinical studies aimed at assessing pathological populations. Two chirp trains were applied concurrently at the same stimulus level but at different repetition rates of 20/sec and 22/sec, respectively. Two overall stimulus levels were investigated: 50 and 30 dB nHL. Because of the 2 Hz difference between the repetition rates, the time difference between the stimuli of the two stimulus trains followed a periodic cycling. The cycling period of 0.5 sec contained ten 20/sec stimuli and eleven 22/sec-stimuli. The response to a single train of chirps with the repetition rate of 20/sec was also recorded. The test group consisted of 11 young adult subjects, all with

  19. Auditory Brainstem Responses in Autistic Children in Comparison with Normal Children

    Directory of Open Access Journals (Sweden)

    Saeed Sarough Farahani

    2008-12-01

    Full Text Available Background and Aim: One of the most important problems of children who suffer from autism is abnormality in receiving and integrating sensory inputs, especially hearing input. It has been shown that brainstem has a key role in receiving, encoding and integrating hearing input. Auditory brainstem response (ABR is a tool by which we can evaluate this function. The purpose of this study was to assess and to compare autistic and normal children brainstem hearing function. Materials and Methods: This case-control study was conducted on thirty (58 ears autistic and thirty (57 ears normal 6-12 years old children. The children with autism were divided into slight and severe subgroups according to Autism Diagnostic Interview-Revised questionnaire. Click-evoked ABR was recorded and compared between groups. Results: There was significant difference between two groups V and III wave latencies and I-III and I-V interpeak latencies (p<0.05. In fact, comparison of the results of autism subgroups with normal children indicated that the latencies of the severe subgroup significantly prolonged. Conclusion: Increasing latencies of ABR waves in severe subgroup maybe due to abnormality in low level of brainstem. Brainstem abnormality may result in exacerbating the symptom of autism. It is therefore suggested that ABR is included in diagnostic test batteries for these patients.

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

    Science.gov (United States)

    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

  1. The impact of maternal smoking on fast auditory brainstem responses.

    Science.gov (United States)

    Kable, Julie A; Coles, Claire D; Lynch, Mary Ellen; Carroll, Julie

    2009-01-01

    Deficits in auditory processing have been posited as one of the underlying neurodevelopmental consequences of maternal smoking during pregnancy that leads to later language and reading deficits. Fast auditory brainstem responses were used to assess differences in the sensory processing of auditory stimuli among infants with varying degrees of prenatal cigarette exposure. Maternal report of consumption of cigarettes and blood samples were collected in the hospital to assess exposure levels and participants were then seen at 6-months. To participate in the study, all infants had to pass the newborn hearing exam or a clinically administered ABR and have no known health problems. After controlling for participant age, maternal smoking during pregnancy was negatively related to latency of auditory brainstem responses. Of several potential covariates, only perinatal complications and maternal alcohol use were also related to latency of the ABR responses and maternal smoking level accounted for significant unique variance after controlling for these factors. These results suggest that the relationship between maternal smoking may lead to disruption in the sensory encoding of auditory stimuli.

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

    Energy Technology Data Exchange (ETDEWEB)

    Aldonate, J; Mercuri, C; Reta, J; Biurrun, J; Bonell, C; Gentiletti, G; Escobar, S; Acevedo, R [Laboratorio de Ingenieria en Rehabilitacion e Investigaciones Neuromusculares y Sensoriales (Argentina); Facultad de Ingenieria, Universidad Nacional de Entre Rios, Ruta 11 - Km 10, Oro Verde, Entre Rios (Argentina)

    2007-11-15

    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.

  3. English consensus protocol evaluating candidacy for auditory brainstem and cochlear implantation in neurofibromatosis type 2.

    Science.gov (United States)

    Tysome, James R; Axon, Patrick R; Donnelly, Neil P; Evans, Dafydd Gareth; Ferner, Rosalie E; O'Connor, Alec F Fitzgerald; Freeman, Simon R; Gleeson, Michael; Halliday, Dorothy; Harris, Frances; Jiang, Dan; Kerr, Richard; King, Andrew; Knight, Richard D; Lloyd, Simon K; Macfarlane, Robert; Mannion, Richard; Mawman, Deborah; O'Driscoll, Martin; Parry, Allyson; Ramsden, James; Ramsden, Richard; Rutherford, Scott A; Saeed, Shakeel R; Thomas, Nick; Vanat, Zebunnisa H

    2013-12-01

    Hearing loss resulting from bilateral vestibular schwannomas (VSs) has a significant effect on the quality of life of patients with neurofibromatosis Type 2 (NF2). A national consensus protocol was produced in England as a guide for cochlear implantation (CI) and auditory brainstem implantation (ABI) in these patients. Consensus statement. English NF2 Service. Clinicians from all 4 lead NF2 units in England. A protocol for the assessment, insertion and rehabilitation of CI and ABI in NF2 patients. Patients should undergo more detailed hearing assessment once their maximum aided speech discrimination score falls below 50% in the better hearing ear. Bamford-Kowal-Bench sentence testing scores below 50% should trigger assessment for auditory implantation, as recommended by the National Institute for Clinical Excellence guidelines on CI. Where this occurs in patients with bilateral stable VS or a unilateral stable VS where the contralateral cochlear nerve was lost at previous surgery, CI should be considered. Where VS surgery is planned, CI should be considered where cochlear nerve preservation is thought possible, otherwise an ABI should be considered. Intraoperative testing using electrically evoked auditory brainstem responses or cochlear nerve action potentials may be used to determine whether a CI or ABI is inserted. The NF2 centers in England agreed on this protocol. Multisite, prospective assessments of standardized protocols for auditory implantation in NF2 provide an essential model for evaluating candidacy and outcomes in this challenging patient population.

  4. Potenciais evocados auditivos de tronco encefálico por frequência específica e de estado estável na audiologia pediátrica: estudo de caso Frequency-specific and steady-state evoked auditory brainstem responses in pediatric audiology: case study

    Directory of Open Access Journals (Sweden)

    Gabriela Ribeiro Ivo Rodrigues

    2009-01-01

    Full Text Available Preconiza-se o diagnóstico até os três meses de idade em crianças com deficiência auditiva congênita. Após a etapa inicial de confirmação do diagnóstico, é necessário que se obtenha limiares precisos nas diferentes frequências, para que seja possível uma adequada seleção, indicação e regulagem de aparelhos de amplificação sonora. Nesse contexto, inserem-se os Potenciais Evocados Auditivos de Tronco Encefálico por Frequência Específica (PEATE-FE e, mais recentemente, os Potenciais Evocados Auditivos de Estado Estável (PEAEE. O objetivo deste estudo de caso foi apresentar os achados das duas técnicas para estimar os limiares auditivos em uma criança de três meses de idade, com perda auditiva neurossensorial bilateral, diagnosticada utilizando-se como primeiro método de avaliação os Potenciais Evocados Auditivos de Tronco Encefálico com estímulo clique, tanto por via aérea como por via óssea. As duas técnicas mostraram-se eficientes para estimar os limiares auditivos, com uma vantagem dos PEAEE com relação ao tempo de duração de exame.It is recommended that congenital hearing loss is identified as early as three months old. After the initial step of confirming the diagnosis, it is necessary to obtain accurate hearing thresholds, allowing an adequate selection, indication and regulation of hearing aids for these children. It is inserted, in this context, the Frequency-Specific Auditory Brainstem Responses (FSABR and, more recently, the Auditory Steady-State Responses (ASSR. The aim of the present study was to describe the findings of the use of both techniques to estimate the auditory thresholds of a three-month-old infant with bilateral sensorineural hearing loss diagnosed using, as primary evaluation method, the click-evoked Auditory Brainstem Responses, with both air and bone stimuli conduction. Both techniques provided reliable findings for estimating auditory thresholds. The ASSR had an advantage regarding

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

    Science.gov (United States)

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

    2010-11-30

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

  6. Neurotoxic effects of rubber factory environment. An auditory evoked potential study.

    Science.gov (United States)

    Kumar, V; Tandon, O P

    1997-01-01

    The effects of rubber factory environment on functional integrity of auditory pathway have been studied in forty rubber factory workers using Brainstem Auditory Evoked Potentials (BAEPs) technique to detect early subclinical impairments. Results indicate that 47 percent of the workers showed abnormalities in prolongations of either peak latencies or interpeak latencies when compared with age and sex matched control subjects not exposed to rubber factory environment. The percent distribution of abnormalities (ears affected) were in the order of extrusion and calendering (75%) > vulcanising (41.66%) > mixing (28.57%) > loading and dispatch (23.07%) > tubing (18.75%) sections of the factory. This incidence of abnormalities may be attributed to solvents being used in these units of rubber factory. These findings suggest that rubber factory environment does affect auditory pathway in the brainstem.

  7. The auditory brainstem response of aged guinea pigs.

    Science.gov (United States)

    Ingham, N J; Thornton, S K; Comis, S D; Withington, D J

    1998-09-01

    The auditory brainstem response (ABR) technique was used to investigate potential dysfunctions in the auditory brainstem of the pigmented guinea pig (Cavia porcellus) associated with biological ageing. Animals aged from 58 days to 4 years 3 months were tested. ABRs were recorded at stimulation intensities from 85 dB HL to -10 dB HL. The auditory thresholds were found to undergo marked elevations in old animals, by an average of 32 dB. From the traces obtained, four positive deflection waves were reliably recorded. The latency of each of the four waves was evaluated at different stimulation intensities in guinea pigs of different ages. Although there was a trend for the latencies to increase in old age, these differences were not statistically significant. Similarly, there were no significant age-related changes in the inter-peak intervals. The latency/intensity functions of the four waves produced parallel curves. However, the curve from the old age group was shifted to the right, by an average of 35 dB, indicative of conductive hearing loss. There was no evidence of retro-cochlear hearing loss. Therefore, it appears that the threshold elevations in the old animals can be accounted for by conductive hearing loss, presumably in the middle ear. In 24% of the old animals tested, no ABR could be elicited. It would appear that these animals had suffered severe sensorineural hearing loss.

  8. Resting Heart Rate and Auditory Evoked Potential

    Directory of Open Access Journals (Sweden)

    Simone Fiuza Regaçone

    2015-01-01

    Full Text Available The objective of this study was to evaluate the association between rest heart rate (HR and the components of the auditory evoked-related potentials (ERPs at rest in women. We investigated 21 healthy female university students between 18 and 24 years old. We performed complete audiological evaluation and measurement of heart rate for 10 minutes at rest (heart rate monitor Polar RS800CX and performed ERPs analysis (discrepancy in frequency and duration. There was a moderate negative correlation of the N1 and P3a with rest HR and a strong positive correlation of the P2 and N2 components with rest HR. Larger components of the ERP are associated with higher rest HR.

  9. Coordinated plasticity in brainstem and auditory cortex contributes to enhanced categorical speech perception in musicians.

    Science.gov (United States)

    Bidelman, Gavin M; Weiss, Michael W; Moreno, Sylvain; Alain, Claude

    2014-08-01

    Musicianship is associated with neuroplastic changes in brainstem and cortical structures, as well as improved acuity for behaviorally relevant sounds including speech. However, further advance in the field depends on characterizing how neuroplastic changes in brainstem and cortical speech processing relate to one another and to speech-listening behaviors. Here, we show that subcortical and cortical neural plasticity interact to yield the linguistic advantages observed with musicianship. We compared brainstem and cortical neuroelectric responses elicited by a series of vowels that differed along a categorical speech continuum in amateur musicians and non-musicians. Musicians obtained steeper identification functions and classified speech sounds more rapidly than non-musicians. Behavioral advantages coincided with more robust and temporally coherent brainstem phase-locking to salient speech cues (voice pitch and formant information) coupled with increased amplitude in cortical-evoked responses, implying an overall enhancement in the nervous system's responsiveness to speech. Musicians' subcortical and cortical neural enhancements (but not behavioral measures) were correlated with their years of formal music training. Associations between multi-level neural responses were also stronger in musically trained listeners, and were better predictors of speech perception than in non-musicians. Results suggest that musicianship modulates speech representations at multiple tiers of the auditory pathway, and strengthens the correspondence of processing between subcortical and cortical areas to allow neural activity to carry more behaviorally relevant information. We infer that musicians have a refined hierarchy of internalized representations for auditory objects at both pre-attentive and attentive levels that supplies more faithful phonemic templates to decision mechanisms governing linguistic operations. © 2014 Federation of European Neuroscience Societies and John Wiley

  10. Delayed auditory brainstem responses in prelingually deaf and late-implanted cochlear implant users

    NARCIS (Netherlands)

    Lammers, Marc; van Eijl, Ruben; van Zanten, Gijsbert; Versnel, Huib; Grolman, Wilko

    2015-01-01

    Neurophysiological studies in animals and humans suggest that severe hearing loss during early development impairs the maturation of the auditory brainstem. To date, studies in humans have mainly focused on the neural activation of the auditory brainstem in children treated with a cochlear implant

  11. Auditory brainstem maturation in normal-hearing infants born preterm : a meta-analysis

    NARCIS (Netherlands)

    Stipdonk, Lottie W; Weisglas-Kuperus, Nynke; Franken, Marie-Christine Jp; Nasserinejad, Kazem; Dudink, Jeroen; Goedegebure, André

    2016-01-01

    AIM: Children born preterm often have neurodevelopmental problems later in life. Abnormal maturation of the auditory brainstem in the presence of normal hearing might be a marker for these problems. We conducted a meta-analysis of auditory brainstem response (ABR) latencies at term age to describe

  12. Auditory Brainstem Responses in Children Treated with Cisplatin

    Directory of Open Access Journals (Sweden)

    Mohammad Kamali

    2012-03-01

    Full Text Available Background and Aim: In view of improvement in therapeutic outcome of cancer treatment in children resulting in increased survival rates and the importance of hearing in speech and language development, this research project was intended to assess the effects of cisplatin group on hearing ability in children aged 6 months to 12 years.Methods: In this cross-sectional study, hearing of 10 children on cisplatin group medication for cancer who met the inclusion criteria was examined by recording auditory brainstem responses (ABR using the three stimulants of click and 4 and 8 kHz tone bursts. All children were examined twice: before drug administration and within 72 hours after receiving the last dose. Then the results were compared with each other.Results: There was a significant difference between hearing thresholds before and after drug administration (p<0.05. Right and left ear threshold comparison revealed no significant difference.Conclusion: Ototoxic effects of cisplatin group were confirmed in this study. Insignificant difference observed in comparing right and left ear hearing thresholds could be due to small sample size. auditory brainstem responses test especially with frequency specificity proved to be a useful method in assessing cisplatin ototoxicity.

  13. Impaired neural conduction in the auditory brainstem of high-risk very preterm infants.

    Science.gov (United States)

    Jiang, Ze D; Chen, Chao

    2014-06-01

    To test the hypothesis that neural conduction in the auditory brainstem is impaired in high-risk very preterm infants. Eighty-two very preterm infants (gestation 28-32 weeks) with various perinatal problems or complications were studied at term using maximum length sequence (MLS) brainstem auditory evoked response (BAER) with click rates 91-910/s. The data were compared with those in 31 age-matched low-risk very preterm infants and 44 normal gestation (term) infants. High-risk very preterm infants showed a general increase in MLS BAER wave latencies and interpeak intervals. Wave V latency, and III-V and I-V intervals in high-risk very preterm infants were significantly longer than in normal term infants at all click rates, particularly higher rates. I-III interval was significantly longer, and III-V/I-III interval ratio was significantly greater at higher rates. These latency and intervals in high-risk very preterm infants were also longer, though relatively less significantly, than in low-risk very preterm infants. Click rate-related changes in major MLS BAER variables in high-risk infants were more significant than in the two groups of controls. There were major abnormalities in MLS BAER variables that mainly reflect central neural conduction in high-risk very preterm infants. The abnormalities were relatively less significant when compared with low-risk very preterm infants than with normal term infants. Neural conduction in the auditory brainstem, mainly the more central regions, is impaired in high-risk very preterm infants. The impairment is largely attributed to the associated perinatal problems, and partially related to very preterm birth. Copyright © 2013. Published by Elsevier Ireland Ltd.

  14. Notched-noise embedded frequency specific chirps for objective audiometry using auditory brainstem responses

    Directory of Open Access Journals (Sweden)

    Farah I. Corona-Strauss

    2012-02-01

    Full Text Available It has been shown recently that chirp-evoked auditory brainstem responses (ABRs show better performance than click stimulations, especially at low intensity levels. In this paper we present the development, test, and evaluation of a series of notched-noise embedded frequency specific chirps. ABRs were collected in healthy young control subjects using the developed stimuli. Results of the analysis of the corresponding ABRs using a time-scale phase synchronization stability (PSS measure are also reported. The resultant wave V amplitude and latency measures showed a similar behavior as for values reported in literature. The PSS of frequency specific chirp-evoked ABRs reflected the presence of the wave V for all stimulation intensities. The scales that resulted in higher PSS are in line with previous findings, where ABRs evoked by broadband chirps were analyzed, and which stated that low frequency channels are better for the recognition and analysis of chirp-evoked ABRs. We conclude that the development and test of the series of notched-noise embedded frequency specific chirps allowed the assessment of frequency specific ABRs, showing an identifiable wave V for different intensity levels. Future work may include the development of a faster automatic recognition scheme for these frequency specific ABRs.

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

    DEFF Research Database (Denmark)

    Fobel, Oliver; Dau, Torsten

    2004-01-01

    This study examines auditory brainstem responses (ABR) elicited by rising frequency chirps. Two chirp stimuli were developed and designed such as to compensate for cochlear travel-time differences across frequency, in order to maximize neural synchrony. One chirp, referred to as the O-chirp, was ......This study examines auditory brainstem responses (ABR) elicited by rising frequency chirps. Two chirp stimuli were developed and designed such as to compensate for cochlear travel-time differences across frequency, in order to maximize neural synchrony. One chirp, referred to as the O...... compared to click responses and to responses obtained with the original chirp as defined in Dau et al. [J. Acoust. Soc. Am. 107(3), 1530–1540 (2000)], referred to here as the M-chirp since it is based on a (linear) cochlea model. The main hypothesis was that, at low and medium stimulation levels, the O......- and A-chirps might produce a larger response than the original M-chirp whose parameters were essentially derived from high-level BM data. The main results of the present study are as follows: (i) All chirps evoked a larger wave-V amplitude than the click stimulus indicating that for the chirps a broader...

  16. Multi-sensory integration in brainstem and auditory cortex.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience

  17. Reduced wave amplitudes of brainstem auditory response in high-risk babies born at 28-32week gestation.

    Science.gov (United States)

    Jiang, Ze Dong; Ping, Li Li

    2016-11-01

    To examine brainstem auditory electrophysiology in high-risk babies born at 28-32week gestation by analysing the amplitudes of wave components in maximum length sequence brainstem auditory evoked response (MLS BAER). 94 preterm babies, ranging in gestation 28-32weeks, with perinatal problems (high-risk) were recruited. The amplitudes of MLS BAER wave components were studied at term age (37-42weeks postconceptional age). Compared with normal term controls, the amplitude in the high-risk preterm babies was significantly smaller at the highest click rate 910/s for wave I (pauditory neuron in such babies is depressed, mainly attributed to or related to the associated perinatal problems. Copyright © 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  18. Evaluation of an auditory brainstem response in icteric neonates

    Directory of Open Access Journals (Sweden)

    Ahmad Talebian

    2017-08-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2017-10-01

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

  1. Analysis of transient otoacoustic emissions and brainstem evoked auditory potentials in neonates with hyperbilirubinemia Análise das emissões otoacústicas transientes e dos potenciais evocados auditivos do tronco encefálico em neonatos com hiperbilirrubinemia

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    Daniela Polo Camargo da Silva

    2009-06-01

    Full Text Available Hyperbilirubinemia is toxic to the auditory pathways and to the central nervous system, leaving sequelae such as hearing loss and encephalopathy. AIM: to assess the hearing of neonates with hyperbilirubinemia, using transient evoked otoacoustic emissions (TOAEs and brainstem evoked auditory potentials (BEAP. Prospective study. MATERIALS AND METHODS: we had two groups: GI (n-25, neonates with hyperbilirubinemia; GII (n-22, neonates without hyperbilirubinemia and without risk factors for hearing loss. All the neonates had up to 60 days of life and were submitted to TOAE and BEAP. RESULTS: 12 neonates from GI and 10 from GII were girls and 13 from GI and 12 from GII were boys. TOAEs were present in all the children, however with lower amplitudes in GI, especially in the frequencies of 2 and 3KHz (p A hiperbilirrubinemia é tóxica às vias auditivas e ao sistema nervoso central, deixando sequelas como surdez e encefalopatia. OBJETIVOS: avaliar a audição de neonatos portadores de hiperbilirrubinemia, utilizando-se a pesquisa das emissões otoacústicas evocadas transientes (EOAET e dos potenciais evocados auditivos do tronco encefálico (PEATE. Estudo prospectivo. CASUÍSTICA E MÉTODOS: Constituíram-se dois grupos: GI (n-25, neonatos com hiperbilirrubinemia; GII (n-22, neonatos sem hiperbilirrubinemia e sem fatores de risco para surdez. Todos os neonatos tinham até 60 dias de vida e foram submetidos à EOAET e ao PEATE. RESULTADOS: 12 neonatos de GI e 10 de GII eram meninas e 13 de GI e 12 de GII eram meninos. As EOAET estavam presentes em todas as crianças, porém com amplitudes menores em GI, especialmente nas frequências de 2 e 3KHz (p < 0,05. No PEATE, observou-se discreto prolongamento de PV e de LI-V em GI. As alterações observadas nesses testes não se correlacionaram aos níveis séricos da bilirrubinemia. CONCLUSÕES: Em neonatos portadores de hiperbilirrubinemia, menores amplitudes das EOAET e discreto prolongamento de PV e de LI

  2. Auditory brainstem responses to stop consonants predict literacy.

    Science.gov (United States)

    Neef, Nicole E; Schaadt, Gesa; Friederici, Angela D

    2017-03-01

    Precise temporal coding of speech plays a pivotal role in sound processing throughout the central auditory system, which, in turn, influences literacy acquisition. The current study tests whether an electrophysiological measure of this precision predicts literacy skills. Complex auditory brainstem responses were analysed from 62 native German-speaking children aged 11-13years. We employed the cross-phaseogram approach to compute the quality of the electrophysiological stimulus contrast [da] and [ba]. Phase shifts were expected to vary with literacy. Receiver operating curves demonstrated a feasible sensitivity and specificity of the electrophysiological measure. A multiple regression analysis resulted in a significant prediction of literacy by delta cross-phase as well as phonological awareness. A further commonality analysis separated a unique variance that was explained by the physiological measure, from a unique variance that was explained by the behavioral measure, and common effects of both. Despite multicollinearities between literacy, phonological awareness, and subcortical differentiation of stop consonants, a combined assessment of behavior and physiology strongly increases the ability to predict literacy skills. The strong link between the neurophysiological signature of sound encoding and literacy outcome suggests that the delta cross-phase could indicate the risk of dyslexia and thereby complement subjective psychometric measures for early diagnoses. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Khullar, Shilpa; Sood, Archana; Sood, Sanjay

    2013-12-01

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

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

    Science.gov (United States)

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

    2015-07-01

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

  5. Human auditory evoked potentials. II - Effects of attention

    Science.gov (United States)

    Picton, T. W.; Hillyard, S. A.

    1974-01-01

    Attention directed toward auditory stimuli, in order to detect an occasional fainter 'signal' stimulus, caused a substantial increase in the N1 (83 msec) and P2 (161 msec) components of the auditory evoked potential without any change in preceding components. This evidence shows that human auditory attention is not mediated by a peripheral gating mechanism. The evoked response to the detected signal stimulus also contained a large P3 (450 msec) wave that was topographically distinct from the preceding components. This late positive wave could also be recorded in response to a detected omitted stimulus in a regular train and therefore seemed to index a stimulus-independent perceptual decision process.

  6. 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.

  7. 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.

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

    DEFF Research Database (Denmark)

    Tang, Y. Z.; Christensen-Dalsgaard, J.; Carr, C. E.

    2012-01-01

    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 lo...

  9. Central conduction time in auditory brainstem response and ear advantage in dichotic listening across menstrual cycle.

    Science.gov (United States)

    Hu, Xu-Jun; Lau, Chi-Chuen

    2017-01-01

    The ovarian hormones fluctuate during the menstrual cycle in women. Such fluctuation of sex hormones, in particular estrogen, is believed to affect the central conduction time in auditory function as well as the language lateralization in cognitive function. However, findings are inconsistent. The underlying mechanisms are also unclear. This paper examined if there was any relation between the central conduction time and the language lateralization at different times during the menstrual cycle. Twenty young women with normal menstrual cycle were tested four times (5 to 7 days apart) across the menstrual cycle. The test battery included the electrophysiological measurement of auditory evoked response in brainstem and the speech performance in dichotic listening with monosyllables as stimulus pairs. The dichotic listening task was conducted under the non-forced, forced-right and forced-left attention. The central conduction time was defined by the time elapsed between two auditory elicited responses along the auditory pathway. The language lateralization in dichotic listening was expressed in ear advantage, which was the right-ear score minus the left-ear score. The results showed that the effects of test time were significant on both the central conduction time and the ear advantage under the forced-left attention. Overall, the interaural difference in the central conduction time correlates with the ear advantage (non-forced attention) at the beginning of the menstrual cycle. The change in central conduction time between two test times correlates significantly with the change in ear advantage under the non-forced and forced-left attention. Conclusively, the central conduction time depends on the time during the menstrual cycle, which in turn may affect the performance in dichotic listening.

  10. Reading ability reflects individual differences in auditory brainstem function, even into adulthood.

    Science.gov (United States)

    Skoe, Erika; Brody, Lisa; Theodore, Rachel M

    2017-01-01

    Research with developmental populations suggests that the maturational state of auditory brainstem encoding is linked to reading ability. Specifically, children with poor reading skills resemble biologically younger children with respect to their auditory brainstem responses (ABRs) to speech stimulation. Because ABR development continues into adolescence, it is possible that the link between ABRs and reading ability changes or resolves as the brainstem matures. To examine these possibilities, ABRs were recorded at varying presentation rates in adults with diverse, yet unimpaired reading levels. We found that reading ability in adulthood related to ABR Wave V latency, with more juvenile response morphology linked to less proficient reading ability, as has been observed for children. These data add to the evidence indicating that auditory brainstem responses serve as an index of the sound-based skills that underlie reading, even into adulthood. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2014-02-01

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

  12. Prolonged auditory brainstem responses in infants with autism

    Science.gov (United States)

    Miron, Oren; Ari‐Even Roth, Daphne; Gabis, Lidia V.; Henkin, Yael; Shefer, Shahar; Dinstein, Ilan

    2015-01-01

    Numerous studies have attempted to identify early physiological abnormalities in infants and toddlers who later develop autism spectrum disorder (ASD). One potential measure of early neurophysiology is the auditory brainstem response (ABR), which has been reported to exhibit prolonged latencies in children with ASD. We examined whether prolonged ABR latencies appear in infancy, before the onset of ASD symptoms, and irrespective of hearing thresholds. To determine how early in development these differences appear, we retrospectively examined clinical ABR recordings of infants who were later diagnosed with ASD. Of the 118 children in the participant pool, 48 were excluded due to elevated ABR thresholds, genetic aberrations, or old testing age, leaving a sample of 70 children: 30 of which were tested at 0–3 months, and 40 were tested at toddlerhood (1.5–3.5 years). In the infant group, the ABR wave‐V was significantly prolonged in those who later developed ASD as compared with case‐matched controls (n = 30). Classification of infants who later developed ASD and case‐matched controls using this measure enabled accurate identification of ASD infants with 80% specificity and 70% sensitivity. In the group of toddlers with ASD, absolute and interpeak latencies were prolonged compared to clinical norms. Findings indicate that ABR latencies are significantly prolonged in infants who are later diagnosed with ASD irrespective of their hearing thresholds; suggesting that abnormal responses might be detected soon after birth. Further research is needed to determine if ABR might be a valid marker for ASD risk. Autism Res 2016, 9: 689–695. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research PMID:26477791

  13. Auditory evoked potentials in children and adolescents with Down syndrome.

    Science.gov (United States)

    Gregory, Letícia; Rosa, Rafael F M; Zen, Paulo R G; Sleifer, Pricila

    2018-01-01

    Down syndrome, or trisomy 21, is the most common genetic alteration in humans. The syndrome presents with several features, including hearing loss and changes in the central nervous system, which may affect language development in children and lead to school difficulties. The present study aimed to investigate group differences in the central auditory system by long-latency auditory evoked potentials and cognitive potential. An assessment of 23 children and adolescents with Down syndrome was performed, and a control group composed of 43 children and adolescents without genetic and/or neurological changes was used for comparison. All children underwent evaluation with pure tone and vocal audiometry, acoustic immitance measures, long-latency auditory evoked potentials, and cognitive potential. Longer latencies of the waves were found in the Down syndrome group than the control group, without significant differences in amplitude, suggesting that individuals with Down syndrome have difficulty in discrimination and auditory memory. It is, therefore, important to stimulate and monitor these children in order to enable adequate development and improve their life quality. We also emphasize the importance of the application of auditory evoked potentials in clinical practice, in order to contribute to the early diagnosis of hearing alterations and the development of more research in this area. © 2017 Wiley Periodicals, Inc.

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

    Directory of Open Access Journals (Sweden)

    Isman Jafar

    2010-06-01

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

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

    Science.gov (United States)

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

    2017-12-01

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

  16. Bottlenose dolphin (Tursiops truncatus) auditory brainstem responses recorded using conventional and randomized stimulation and averaging.

    Science.gov (United States)

    Finneran, James J

    2017-08-01

    Auditory brainstem response (ABR) measurements using conventional averaging (i.e., constant interstimulus interval, ISI) are limited to stimulus rates low enough to prevent overlapping of the ABRs to successive stimuli. To overcome this limitation, stimuli may be presented at high rates using pseudorandom sequences (e.g., maximum length sequences) or quasi-periodic sequences; however, these methods restrict the available stimulus sequences and require deconvolution to recover the ABR from the overlapping responses. Randomized stimulation and averaging (RSA) is an alternate method where evoked responses at high rates are obtained by averaging responses to stimuli with ISIs drawn from a random distribution. The RSA method enables precise control over stimulus jitter, is flexible with respect to stimulus sequence parameters, and does not require deconvolution to extract the ABR waveform. In this study, ABRs were measured in three normal-hearing dolphins using conventional averaging and RSA. Results show the RSA method to be effective in dolphins if the ISI jitter ≥ ∼1.5 ms and that the influence of stimulus artifacts in the averaged ABR can be substantially reduced by alternating stimulus polarity on successive presentations rather than employing digital blanking or iterative processes.

  17. Normative auditory brainstem response data for hearing threshold and neuro-otological diagnosis in the dog.

    Science.gov (United States)

    Shiu, J N; Munro, K J; Cox, C L

    1997-03-01

    There is growing interest in the application of auditory brainstem response (ABR) audiometry for hearing assessment in dogs. The technique is far from standardised, however, resulting in large discrepancies between studies. This study aimed to obtain normative data, under clearly defined conditions, for two breeds of significantly different size; head size being a potential factor determining ABR latency values. The subjects, 20 dalmatians and 20 Jack Russell terriers, were sedated prior to ABR testing, and subcutaneous scalp electrodes used to detect the evoked potential elicited by a click stimulus presented via insert earphones. The mean ABR thresholds for the two breeds, 0 and -5 decibels re normal hearing level (dB nHL), respectively, were very similar to those for humans. The latency values of the main ABR waves and the interval between them were statistically significantly smaller for the smaller breed, but there was no correlation with head size within either breed. The results provide a baseline to assist with confirmation of hearing impairment and neuro-otological diagnosis in the dog.

  18. Binaural interaction in human auditory brainstem response compared for tone-pips and rectangular clicks under conditions of auditory and visual attention.

    Science.gov (United States)

    Ikeda, Kazunari

    2015-07-01

    Binaural interaction in the auditory brainstem response (ABR) represents the discrepancy between the binaural waveform and the sum of monaural ones. A typical ABR binaural interaction in humans is a reduction of the binaural amplitude compared to the monaural sum at the wave-V latency, i.e., the DN1 component. It has been considered that the DN1 is mainly elicited by high frequency components of stimuli whereas some studies have shown the contribution of low-to-middle frequency components to the DN1. To examine this issue, the present study compared the ABR binaural interaction elicited by tone pips (1 kHz, 10-ms duration) with the one by clicks (a rectangular wave, 0.1-ms duration) presented at 80 dB peak equivalent SPL and a fixed stimulus onset interval (180 ms). The DN1 due to tone pips was vulnerable compared to the click-evoked DN1. The pip-evoked DN1 was significantly detected under auditory attention whereas it failed to reach significance under visual attention. The click-evoked DN1 was robustly present for the two attention conditions. The current results might confirm the high frequency sound contribution to the DN1 elicitation. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Cochlear Responses and Auditory Brainstem Response Functions in Adults with Auditory Neuropathy/ Dys-Synchrony and Individuals with Normal Hearing

    Directory of Open Access Journals (Sweden)

    Zahra Jafari

    2007-06-01

    Full Text Available Background and Aim: Physiologic measures of cochlear and auditory nerve function may be of assis¬tance in distinguishing between hearing disorders due primarily to auditory nerve impairment from those due primarily to cochlear hair cells dysfunction. The goal of present study was to measure of co-chlear responses (otoacoustic emissions and cochlear microphonics and auditory brainstem response in some adults with auditory neuropathy/ dys-synchrony and subjects with normal hearing. Materials and Methods: Patients were 16 adults (32 ears in age range of 14-30 years with auditory neu¬ropathy/ dys-synchrony and 16 individuals in age range of 16-30 years from both sexes. The results of transient otoacoustic emissions, cochlear microphonics and auditory brainstem response measures were compared in both groups and the effects of age, sex, ear and degree of hearing loss were studied. Results: The pure-tone average was 48.1 dB HL in auditory neuropathy/dys-synchrony group and the fre¬quency of low tone loss and flat audiograms were higher among other audiogram's shapes. Transient oto¬acoustic emissions were shown in all auditory neuropathy/dys-synchrony people except two cases and its average was near in both studied groups. The latency and amplitude of the biggest reversed co-chlear microphonics response were higher in auditory neuropathy/dys-synchrony patients than control peo¬ple significantly. The correlation between cochlear microphonics amplitude and degree of hearing loss was not significant, and age had significant effect in some cochlear microphonics measures. Audi-tory brainstem response had no response in auditory neuropathy/dys-synchrony patients even with low stim¬uli rates. Conclusion: In adults with speech understanding worsen than predicted from the degree of hearing loss that suspect to auditory neuropathy/ dys-synchrony, the frequency of low tone loss and flat audiograms are higher. Usually auditory brainstem response is absent in

  20. Motor-evoked potentials (MEP) during brainstem surgery to preserve corticospinal function.

    Science.gov (United States)

    Sarnthein, Johannes; Bozinov, Oliver; Melone, Angelina Graziella; Bertalanffy, Helmut

    2011-09-01

    Brainstem surgery bears a risk of damage to the corticospinal tract (CST). Motor-evoked potentials (MEPs) are used intraoperatively to monitor CST function in order to detect CST damage at a reversible stage and thus impede permanent neurological deficits. While the method of MEP is generally accepted, warning criteria in the context of brainstem surgery still have to be agreed on. We analyzed 104 consecutive patients who underwent microsurgical resection of lesions affecting the brainstem. Motor grade was documented prior to surgery, early postoperatively and at discharge. A baseline MEP stimulation intensity threshold was defined and intraoperative testing aimed to keep MEP response amplitude constant. MEPs were considered deteriorated and the surgical team was notified whenever the threshold was elevated by ≥20 mA or MEP response fell under 50%. On the first postoperative day, 18 patients experienced new paresis that resolved by discharge in 11. MEPs deteriorated in 39 patients, and 16 of these showed new postoperative paresis, indicating a 41% risk of new paresis. In the remaining 2/18 patients, intraoperative MEPs were stable, although new paresis appeared postoperatively. In one of these patients, intraoperative hemorrhage caused postoperative swelling, and the new motor deficit persisted until discharge. Of all 104 patients, 7 deteriorated in motor grade at discharge, 92 remained unchanged, and 5 patients have improved. Adjustment of surgical strategy contributed to good motor outcome in 33/39 patients. MEP monitoring may help significantly to prevent motor deficits during demanding neurosurgical procedures on the brainstem.

  1. Evoked response audiometry used in testing auditory organs of miners

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, T.; Klepacki, J.; Wagstyl, R.

    1980-01-01

    The evoked response audiometry method of testing hearing loss is presented and the results of comparative studies using subjective tonal audiometry and evoked response audiometry in tests of 56 healthy men with good hearing are discussed. The men were divided into three groups according to age and place of work: work place without increased noise; work place with noise and vibrations (at drilling machines); work place with noise and shocks (work at excavators in surface coal mines). The ERA-MKII audiometer produced by the Medelec-Amplaid firm was used. Audiometric threshhold curves for the three groups of tested men are given. At frequencies of 500, 1000 and 4000 Hz mean objective auditory threshhold was shifted by 4-9.5 dB in comparison to the subjective auditory threshold. (21 refs.) (In Polish)

  2. Developmental alterations of the auditory brainstem centers--pathogenetic implications in Sudden Infant Death Syndrome.

    Science.gov (United States)

    Lavezzi, Anna M; Ottaviani, Giulia; Matturri, Luigi

    2015-10-15

    Sudden Infant Death Syndrome (SIDS), despite the success of campaigns to reduce its risks, is the leading cause of infant death in the Western world. Even though the pathogenesis remains unexplained, brainstem abnormalities of the neuronal network that mediates breathing and protective responses to asphyxia, particularly in the arousal phase from sleep, are believed to play a fundamental role. This is the first study to identify, in SIDS, developmental defects of specific brainstem centers involved in hearing pathways, particularly in the cochlear and vestibular nuclei, in the superior olivary complex and in the inferior colliculus, suggesting a possible influence of the acoustic system on respiratory activity. In 49 SIDS cases and 20 controls an in-depth anatomopathological examination of the autonomic nervous system was performed, with the main aim of detecting developmental alterations of brainstem structures controlling both the respiratory and auditory activities. Overall, a significantly higher incidence of cytoarchitectural alterations of both the auditory and respiratory network components were observed in SIDS victims compared with matched controls. Even if there is not sufficient evidence to presume that developmental defects of brainstem auditory structures can affect breathing, our findings, showing that developmental deficit in the control respiratory areas are frequently accompanied by alterations of auditory structures, highlight an additional important element for the understanding the pathogenetic mechanism of SIDS. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

    Rafique, Irfan; Wennervaldt, Kasper; Melchiors, Jacob

    2016-01-01

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

  4. [Increase in intracranial pressure in monitoring brain stem auditory evoked potentials using headphones].

    Science.gov (United States)

    Schwarz, G; Pfurtscheller, G; Tritthart, H; List, W F

    1988-11-01

    Ten measurements of intracranial pressure (ICP) (ventricular n = 5, epidural n = 3) in 8 patients (3 after aneurysm surgery, 5 with head trauma) were performed before and after application of conventional headphones for stimulating brainstem auditory evoked potentials (BAEP). The effects of miniature earphones and sound tubes on ICP were also studied. In 7 of 10 measurements after application of headphones a reversible increase of ICP (mean 26 +/- 19% in patients with ICP greater than 10 mmHg was recorded; in 3 patients (ICP less than or equal to 10 mgHg) no changes of ICP were seen. Using miniature earphones and sound tubes no increase of ICP was noted in any patient, and hence these can be recommended for stimulating BAEP in case of increased ICP.

  5. Auditory brainstem responses predict auditory nerve fiber thresholds and frequency selectivity in hearing impaired chinchillas.

    Science.gov (United States)

    Henry, Kenneth S; Kale, Sushrut; Scheidt, Ryan E; Heinz, Michael G

    2011-10-01

    Noninvasive auditory brainstem responses (ABRs) are commonly used to assess cochlear pathology in both clinical and research environments. In the current study, we evaluated the relationship between ABR characteristics and more direct measures of cochlear function. We recorded ABRs and auditory nerve (AN) single-unit responses in seven chinchillas with noise-induced hearing loss. ABRs were recorded for 1-8 kHz tone burst stimuli both before and several weeks after 4 h of exposure to a 115 dB SPL, 50 Hz band of noise with a center frequency of 2 kHz. Shifts in ABR characteristics (threshold, wave I amplitude, and wave I latency) following hearing loss were compared to AN-fiber tuning curve properties (threshold and frequency selectivity) in the same animals. As expected, noise exposure generally resulted in an increase in ABR threshold and decrease in wave I amplitude at equal SPL. Wave I amplitude at equal sensation level (SL), however, was similar before and after noise exposure. In addition, noise exposure resulted in decreases in ABR wave I latency at equal SL and, to a lesser extent, at equal SPL. The shifts in ABR characteristics were significantly related to AN-fiber tuning curve properties in the same animal at the same frequency. Larger shifts in ABR thresholds and ABR wave I amplitude at equal SPL were associated with greater AN threshold elevation. Larger reductions in ABR wave I latency at equal SL, on the other hand, were associated with greater loss of AN frequency selectivity. This result is consistent with linear systems theory, which predicts shorter time delays for broader peripheral frequency tuning. Taken together with other studies, our results affirm that ABR thresholds and wave I amplitude provide useful estimates of cochlear sensitivity. Furthermore, comparisons of ABR wave I latency to normative data at the same SL may prove useful for detecting and characterizing loss of cochlear frequency selectivity. Copyright © 2011 Elsevier B.V. All

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

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    Zeena Venkatacheluvaiah Pushpalatha

    2016-01-01

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

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

    Science.gov (United States)

    Pushpalatha, Zeena Venkatacheluvaiah; Konadath, Sreeraj

    2016-01-01

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

  8. An alternative strategy for universal infant hearing screening in tertiary hospitals with a high delivery rate, within a developing country, using transient evoked oto-acoustic emissions and brainstem evoked response audiometry.

    Science.gov (United States)

    Mathur, N N; Dhawan, R

    2007-07-01

    To formulate an alternative strategy for universal infants hearing screening in an Indian tertiary referral hospital with a high delivery rate, which could be extended to similar situations in other developing countries. The system should be able to diagnose, in a timely fashion, all infants with severe and profound hearing losses. One thousand newborn were randomly selected. All underwent testing with transient evoked oto-acoustic emissions (TEOAE) in the first 48 hours of life. All TEOAE failures were followed up and repeat tests were performed at three weeks, three months and six months of age. Infants with acceptable TEOAE results at any of the four ages were discharged from the study. Infants with unacceptable TEOAE results at all the four ages underwent brainstem evoked response audiometry and oto-endoscopy. The 'pass rate' for TEOAE testing was calculated for all four ages. The time taken to perform TEOAE and brainstem evoked response audiometry was recorded for all subjects. These recordings were statistically analysed to find the most suitable strategy for universal hearing screening in our hospital. The pass rate for TEOAE was 79.0 per cent at audiometry. Obstructed and collapsed external auditory canals were the two factors that significantly affected the specificity of TEOAE in infants results are generated, such that a larger number must undergo brainstem evoked response audiometry, wasting time and resources. This can easily be avoided by delaying TEOAE screening until three months of age, when it has a substantially lower false positive outcome. We expect that implementation of this alternative strategy in our hospital will maximise the benefits of such a programme.

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

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    Shizuka Seino

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS: It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms.

  10. 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.

  11. The division of attention and the human auditory evoked potential

    Science.gov (United States)

    Hink, R. F.; Van Voorhis, S. T.; Hillyard, S. A.; Smith, T. S.

    1977-01-01

    The sensitivity of the scalp-recorded, auditory evoked potential to selective attention was examined while subjects responded to stimuli presented to one ear (focused attention) and to both ears (divided attention). The amplitude of the N1 component was found to be largest to stimuli in the ear upon which attention was to be focused, smallest to stimuli in the ear to be ignored, and intermediate to stimuli in both ears when attention was divided. The results are interpreted as supporting a capacity model of attention.

  12. 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

  13. Evaluting the effect of long-term monaural hearing aid usage via auditory brainstem response

    Directory of Open Access Journals (Sweden)

    Tayebeh Ahmadi

    2014-01-01

    Full Text Available Background and Aim: Studies have shown that long-term use of monaural hearing aid in symmetrical hearing losses may lead to physiological changes. In this research, the possibility of plasticity occurrence in bilaterally hearing impaired listeners fitted with only one hearing aid was investigated.Methods: Our study was carried out on 12 elderly listeners with a mean age of 61.92 years who had symmetrical moderate to severe sensory neural hearing loss in both ears. All of the participants had minimum monaural hearing aid experience of 2 years. We used auditory brainstem response (ABR testing in order to compare absolute latency and amplitude of wave V between the two ears of cases. Air conduction click stimuli were presented monaurally at 80, 90 and 100 dB nHL.Results: Despite the shorter absolute latency of wave V in the fitted ear, no significant difference was found between the two ears (p>0.389. The difference between wave V amplitude of both ears was greater in 90 dB nHL level (p=0.043. Women showed shorter mean latency than men and the mean amplitude of women was greater than men. Significant gender difference was observed in absolute latency of wave V (p<0.037.Conclusion: Our findings indicate that the use of monaural hearing aid in symmetrical hearing losses can induce neural plasticity within auditory brainstem pathways which can be displayed by auditory brainstem response test.

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

    Science.gov (United States)

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

    2017-08-02

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

  15. One Year of Musical Training Affects Development of Auditory Cortical-Evoked Fields in Young Children

    Science.gov (United States)

    Fujioka, Takako; Ross, Bernhard; Kakigi, Ryusuke; Pantev, Christo; Trainor, Laurel J.

    2006-01-01

    Auditory evoked responses to a violin tone and a noise-burst stimulus were recorded from 4- to 6-year-old children in four repeated measurements over a 1-year period using magnetoencephalography (MEG). Half of the subjects participated in musical lessons throughout the year; the other half had no music lessons. Auditory evoked magnetic fields…

  16. The effects of click and masker spectrum on the auditory brainstem response of bottlenose dolphins (Tursiops truncatus).

    Science.gov (United States)

    Mulsow, Jason; Finneran, James J; Houser, Dorian S; Burkard, Robert F

    2016-10-01

    Two experiments were performed that investigated the effects of (1) click level and (2) continuous broadband noise on the binaural auditory brainstem response (ABR) of normal-hearing and hearing-impaired bottlenose dolphins (Tursiops truncatus). In addition to spectrally uncompensated clicks and noise, stimuli were digitally compensated to achieve "white" spectra (flat spectral density level) or "pink" spectra (spectral density level rolling off at -3 dB/octave). For experiment 1, in all spectral conditions, ABR peak latencies increased and peak amplitudes decreased with decreasing click level, but interwave intervals changed little. Latency-intensity function (LIF) slopes ranged from -3 to -11 μs/dB. The LIF slopes of ABR peaks evoked by uncompensated clicks were steeper in dolphins with hearing loss. Click level was held constant during experiment 2, and the effect of bilaterally delivered broadband masking noise on the ABR was investigated. Clicks and noise were filtered to create a pink click/noise condition and a white click/noise condition. With increasing levels of masking noise, peak latencies increased (although only P1-P4 white reached significance), peak amplitudes decreased, and interpeak intervals increased (although not significantly). These effects are compared to results reported for terrestrial mammals, and implications for auditory health assessment and biosonar function are discussed.

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

    Directory of Open Access Journals (Sweden)

    Melissa A Tarasenko

    2014-10-01

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

  18. 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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  1. Auditory evoked responses upon awakening from sleep in human subjects.

    Science.gov (United States)

    Ferrara, M; De Gennaro, L; Ferlazzo, F; Curcio, G; Barattucci, M; Bertini, M

    2001-09-14

    The hypothesis that a state of hypoarousal upon awakening should lead to a decrease in amplitude and an increase in latency of the N1-P2 components of the Auditory Evoked Potentials (AEPs) as compared to presleep wakefulness levels, was evaluated after two nocturnal awakenings and after the final morning awakening from a 7.5-h night of sleep. The amplitude of the N1-P2 complex was reduced upon awakening as compared to presleep wakefulness levels, but only following the first nocturnal awakening, scheduled after the first 2 h of sleep. This result is interpreted as indicating a link between slow wave sleep amount, mainly present during the first part of the night, and lowered levels of brain activation upon awakening. The reaction times, recorded concomitantly to AEPs, were more sensitive to the negative effects of sleep inertia.

  2. Auditory evoked field measurement using magneto-impedance sensors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, K., E-mail: o-kabou@echo.nuee.nagoya-u.ac.jp; Tajima, S.; Song, D.; Uchiyama, T. [Graduate School of Engineering, Nagoya University, Nagoya (Japan); Hamada, N.; Cai, C. [Aichi Steel Corporation, Tokai (Japan)

    2015-05-07

    The magnetic field of the human brain is extremely weak, and it is mostly measured and monitored in the magnetoencephalography method using superconducting quantum interference devices. In this study, in order to measure the weak magnetic field of the brain, we constructed a Magneto-Impedance sensor (MI sensor) system that can cancel out the background noise without any magnetic shield. Based on our previous studies of brain wave measurements, we used two MI sensors in this system for monitoring both cerebral hemispheres. In this study, we recorded and compared the auditory evoked field signals of the subject, including the N100 (or N1) and the P300 (or P3) brain waves. The results suggest that the MI sensor can be applied to brain activity measurement.

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

    Directory of Open Access Journals (Sweden)

    Erika eSkoe

    2013-09-01

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

  4. 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.

  5. The Role of the Auditory Brainstem in Processing Musically Relevant Pitch

    Science.gov (United States)

    Bidelman, Gavin M.

    2013-01-01

    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. PMID:23717294

  6. [Loss of brain stem auditory evoked potential waves I and II during controlled hypotension].

    Science.gov (United States)

    Papadopoulos, G; Lang, M; Link, J; Schäfer, M; Schaffartzik, W; Eyrich, K; Bornfeld, N; Foerster, M H

    1995-11-01

    For surgical removal of a malignant choroid melanoma, it is necessary to reduce systolic blood pressure to around 50-60 mmHg in order to prevent choroidal haemorrhages. However, blood pressure reduction is associated with the risk of cerebral ischaemia. We report a patient with a malignant choroid melanoma in whom waves I and II of the brainstem auditory evoked potentials (BAEP) disappeared during surgery under controlled arterial hypotension and hypothermia (31.1 degrees C). The waves could be recorded again immediately after the mean arterial pressure was increased from 48 to 77 mmHg. The oesophageal temperature had dropped by 0.3 degrees C at this time. The 2-channel electroencephalogram (EEG) showed no irregularities during this time period. A bilateral, reversible, apparently blood-pressure-dependent loss of waves I and II during arterial hypotension despite a normal EEG has to our knowledge not been previously described in the literature. The isolated loss of waves I and II with maintenance of waves III, IV, and V is unusual. The literature contains reports of acoustic neurinoma patients in whom only wave V could be recorded. This is regarded as an indication of continued impulse conduction despite the loss of waves I to IV. Others have observed a patient with temporary and reversible loss of BAEP wave I due to vasospasm of the internal auditory artery that apparently occurred during or shortly after manipulation of the internal auditory meatus. Assuming anatomic peculiarities in the blood supply to the generators of the BAEP waves, a stenosis of the basilar artery could be considered as the cause of the bilateral reversible loss of waves I and II. Another potential source could be induced hypothermia, but this does not seem very likely because the patient's temperature was 0.3 degrees C lower at the return of the waves than at their loss.

  7. Auditory evoked potentials in a newborn Wistar rat model of hyperbilirubinemia.

    Science.gov (United States)

    Gökdoğan, Çağıl; Genç, Aydan; Gülbahar, Özlem; Gökdoğan, Ozan; Helvacı, Ayşe; Bezgin, Selin Üstün; Memiş, Leyla

    2016-01-01

    Hyperbilirubinemia is a common health problem in newborns. Its effects can be different according to the level and duration of the hyperbilirubinemia. The toxic effect of bilirubin on the auditory system can be seen as a sensory neural hearing loss or auditory neuropathy spectrum disorder (ANSD). The purpose of our study was to determine the effects of toxic bilirubin level on the auditory system by using Auditory Brainstem Response audiometry. Rats are used as animal models due to their low cost and easy attainability. Auditory Brainstem Response was used for auditory assessment. In this study, three groups were established: experimental, control and placebo groups. In the experimental group, which consists of rats with hyperbilirubinemia, sensory neural hearing loss was found bilaterally in 4 rats (66.67%) and unilaterally in 2 rats (16.67%) and auditory neuropathy spectrum disorder was found unilaterally in 1 rat (8.33%). Auditory Brainstem Response thresholds were significantly elevated compared to control and placebo groups (p<0.05). Hyperbilirubinemia of newborn rats may result both in sensory neural hearing loss and auditory neuropathy spectrum disorder. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  8. Auditory evoked potentials in a newborn Wistar rat model of hyperbilirubinemia

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    Çagil Gökdogan

    2016-04-01

    Full Text Available ABSTRACT INTRODUCTION: Hyperbilirubinemia is a common health problem in newborns. Its effects can be different according to the level and duration of the hyperbilirubinemia. The toxic effect of bilirubin on the auditory system can be seen as a sensory neural hearing loss or auditory neuropathy spectrum disorder (ANSD. OBJECTIVE: The purpose of our study was to determine the effects of toxic bilirubin level on the auditory system by using Auditory Brainstem Response audiometry. METHODS: Rats are used as animal models due to their low cost and easy attainability. Auditory Brainstem Response was used for auditory assessment. In this study, three groups were established: experimental, control and placebo groups. RESULTS: In the experimental group, which consists of rats with hyperbilirubinemia, sensory neural hearing loss was found bilaterally in 4 rats (66.67% and unilaterally in 2 rats (16.67% and auditory neuropathy spectrum disorder was found unilaterally in 1 rat (8.33%. Auditory Brainstem Response thresholds were significantly elevated compared to control and placebo groups (p < 0.05. CONCLUSION: Hyperbilirubinemia of newborn rats may result both in sensory neural hearing loss and auditory neuropathy spectrum disorder.

  9. Language impairment is reflected in auditory evoked fields.

    Science.gov (United States)

    Pihko, Elina; Kujala, Teija; Mickos, Annika; Alku, Paavo; Byring, Roger; Korkman, Marit

    2008-05-01

    Specific language impairment (SLI) is diagnosed when a child has problems in producing or understanding language despite having a normal IQ and there being no other obvious explanation. There can be several associated problems, and no single underlying cause has yet been identified. Some theories propose problems in auditory processing, specifically in the discrimination of sound frequency or rapid temporal frequency changes. We compared automatic cortical speech-sound processing and discrimination between a group of children with SLI and control children with normal language development (mean age: 6.6 years; range: 5-7 years). We measured auditory evoked magnetic fields using two sets of CV syllables, one with a changing consonant /da/ba/ga/ and another one with a changing vowel /su/so/sy/ in an oddball paradigm. The P1m responses for onsets of repetitive stimuli were weaker in the SLI group whereas no significant group differences were found in the mismatch responses. The results indicate that the SLI group, having weaker responses to the onsets of sounds, might have slightly depressed sensory encoding.

  10. Neurogenic vestibular evoked potentials using a tone pip auditory stimulus.

    Science.gov (United States)

    Papathanasiou, E S; Zamba-Papanicolaou, E; Pantziaris, M; Kleopas, K; Kyriakides, T; Papacostas, S; Pattichis, C; Iliopoulos, I; Piperidou, C

    2004-01-01

    To obtain neurogenic vestibular evoked potentials (NVESTEPs) with surface scalp recording using a tone pip auditory stimulus. Fourteen neurologically normal volunteers (Age range 26-45 years, 10 females and 4 males), and two patients with sensorineural hearing loss and possible multiple sclerosis respectively, were examined. Two channel recordings were obtained, the first channel being P3 referred to Fpz, and the second channel being P4 referred to Fpz. A 1 kHz tone pip stimulus with two cycles was delivered via headphones monoaurally with contralateral masking noise. A consistent negative wave with a mean absolute latency of 4.72 msec was obtained, which we have named N5. 25% of the ears tested had better responses at the ipsilateral parietal electrode. In the patient with bilateral sensorineural hearing loss, NVESTEPs was present, suggesting that the NVESTEP is not a cochlear response. In the patient with possible multiple sclerosis, an abnormal NVESTEP response and a normal BAEP response were found. Use of a tone-pip rather than a click auditory stimulus allows a lower click intensity to be used in the production of NVESTEP responses, leads to a shorter testing time, and is therefore more comfortable for the patient. This study adds to our impression that the NVESTEP may be a physiological response that can be used to assess the vestibular system and is different from the BAEP response. Further testing in patients with symptoms of dizziness and with disorders specific for the vestibular nerve is required.

  11. Protocol to collect late latency auditory evoked potentials.

    Science.gov (United States)

    Ventura, Luzia Maria Pozzobom; Alvarenga, Kátia de Freitas; Costa Filho, Orozimbo Alves

    2009-01-01

    Long Latency Auditory Evoked Potentials (LLAEP) represents a number of electrical changes occurring in the central nervous system, resulting from stimulation of the auditory sensorial pathways. Many studies approach the use of these potentials controlling the artifact created by eye movement with the use of equipment with a large number of channels. However, what happens is very different in Brazilian clinical practice, where the equipment used has a very limited number of channels. to compare the two methods used to control the artifacts created by eye movements during LLAEP capture using two recording channels. this is a prospective study with the application of two LLAEP capturing methods (eye artifact subtraction and rejection limit control) in 10 normal hearing individuals. we did not observe statistically significant differences concerning the latency values obtained with the use of both methods, only concerning amplitude values. both methods were efficient to capture the LLAEP and to control the eye movement artifact. The rejection limit control method produced greater amplitude values.

  12. Auditory- and Vestibular-Evoked Potentials Correlate with Motor and Non-Motor Features of Parkinson’s Disease

    Science.gov (United States)

    Shalash, Ali Soliman; Hassan, Dalia Mohamed; Elrassas, Hanan Hani; Salama, Mohamed Mosaad; Méndez-Hernández, Edna; Salas-Pacheco, José M.; Arias-Carrión, Oscar

    2017-01-01

    Degeneration of several brainstem nuclei has been long related to motor and non-motor symptoms (NMSs) of Parkinson’s disease (PD). Nevertheless, due to technical issues, there are only a few studies that correlate that association. Brainstem auditory-evoked potential (BAEP) and vestibular-evoked myogenic potential (VEMP) responses represent a valuable tool for brainstem assessment. Here, we investigated the abnormalities of BAEPs, ocular VEMPs (oVEMPs), and cervical VEMPs (cVEMPs) in patients with PD and its correlation to the motor and NMSs. Fifteen patients diagnosed as idiopathic PD were evaluated by Unified Parkinson’s Disease Rating Scale and its subscores, Hoehn and Yahr scale, Schwab and England scale, and Non-Motor Symptoms Scale. PD patients underwent pure-tone, speech audiometry, tympanometry, BAEP, oVEMPs, and cVEMPs, and compared to 15 age-matched control subjects. PD subjects showed abnormal BAEP wave morphology, prolonged absolute latencies of wave V and I–V interpeak latencies. Absent responses were the marked abnormality seen in oVEMP. Prolonged latencies with reduced amplitudes were seen in cVEMP responses. Rigidity and bradykinesia were correlated to the BAEP and cVEMP responses contralateral to the clinically more affected side. Contralateral and ipsilateral cVEMPs were significantly correlated to sleep (p = 0.03 and 0.001), perception (p = 0.03), memory/cognition (p = 0.025), and urinary scores (p = 0.03). The oVEMP responses showed significant correlations to cardiovascular (p = 0.01) and sexual dysfunctions (p = 0.013). PD is associated with BAEP and VEMP abnormalities that are correlated to the motor and some non-motor clinical characteristics. These abnormalities could be considered as potential electrophysiological biomarkers for brainstem dysfunction and its associated motor and non-motor features. PMID:28289399

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

    Directory of Open Access Journals (Sweden)

    Bahram Jalaei

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Ghassem Mohammadkhani

    2009-12-01

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

  15. Middle components of the auditory evoked response in bilateral temporal lobe lesions. Report on a patient with auditory agnosia

    DEFF Research Database (Denmark)

    Parving, A; Salomon, G; Elberling, Claus

    1980-01-01

    An investigation of the middle components of the auditory evoked response (10--50 msec post-stimulus) in a patient with auditory agnosia is reported. Bilateral temporal lobe infarctions were proved by means of brain scintigraphy, CAT scanning, and regional cerebral blood flow measurements. The mi...

  16. Effect of the Level of Anesthesia on the Auditory Brainstem Response in the Emei Music Frog (Babina daunchina.

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    Jianguo Cui

    Full Text Available Anesthesia is known to affect the auditory brainstem response (ABR in mice, rats, birds and lizards. The present study investigated how the level of anesthesia affects ABR recordings in an amphibian species, Babina daunchina. To do this, we compared ABRs evoked by tone pip stimuli recorded from 35 frogs when Tricaine methane sulphonate (MS-222 anesthetic immersion times varied from 0, 5 and 10 minutes after anesthesia induction at sound frequencies between 0.5 and 6 kHz. ABR thresholds increased significantly with immersion time across the 0.5 kHz to 2.5 kHz frequency range, which is the most sensitive frequency range for hearing and the main frequency range of male calls. There were no significant differences for anesthetic levels across the 3 kHz to 6 kHz range. ABR latency was significantly longer in the 10 min group than in the 0 and 5 min groups at frequencies of 0.5, 1.0, 1.5, 2.5 kHz, while ABR latency did not differ across the 3 kHz to 4 kHz range and at 2.0 kHz. Taken together, these results show that the level of anesthesia affects the amplitude, threshold and latency of ABRs in frogs.

  17. Channel-noise-induced stochastic facilitation in an auditory brainstem neuron model

    Science.gov (United States)

    Schmerl, Brett A.; McDonnell, Mark D.

    2013-11-01

    Neuronal membrane potentials fluctuate stochastically due to conductance changes caused by random transitions between the open and closed states of ion channels. Although it has previously been shown that channel noise can nontrivially affect neuronal dynamics, it is unknown whether ion-channel noise is strong enough to act as a noise source for hypothesized noise-enhanced information processing in real neuronal systems, i.e., “stochastic facilitation”. Here we demonstrate that biophysical models of channel noise can give rise to two kinds of recently discovered stochastic facilitation effects in a Hodgkin-Huxley-like model of auditory brainstem neurons. The first, known as slope-based stochastic resonance (SBSR), enables phasic neurons to emit action potentials that can encode the slope of inputs that vary slowly relative to key time constants in the model. The second, known as inverse stochastic resonance (ISR), occurs in tonically firing neurons when small levels of noise inhibit tonic firing and replace it with burstlike dynamics. Consistent with previous work, we conclude that channel noise can provide significant variability in firing dynamics, even for large numbers of channels. Moreover, our results show that possible associated computational benefits may occur due to channel noise in neurons of the auditory brainstem. This holds whether the firing dynamics in the model are phasic (SBSR can occur due to channel noise) or tonic (ISR can occur due to channel noise).

  18. Short GSM mobile phone exposure does not alter human auditory brainstem response

    Directory of Open Access Journals (Sweden)

    Thuróczy György

    2007-11-01

    Full Text Available Abstract Background There are about 1.6 billion GSM cellular phones in use throughout the world today. Numerous papers have reported various biological effects in humans exposed to electromagnetic fields emitted by mobile phones. The aim of the present study was to advance our understanding of potential adverse effects of the GSM mobile phones on the human hearing system. Methods Auditory Brainstem Response (ABR was recorded with three non-polarizing Ag-AgCl scalp electrodes in thirty young and healthy volunteers (age 18–26 years with normal hearing. ABR data were collected before, and immediately after a 10 minute exposure to 900 MHz pulsed electromagnetic field (EMF emitted by a commercial Nokia 6310 mobile phone. Fifteen subjects were exposed to genuine EMF and fifteen to sham EMF in a double blind and counterbalanced order. Possible effects of irradiation was analyzed by comparing the latency of ABR waves I, III and V before and after genuine/sham EMF exposure. Results Paired sample t-test was conducted for statistical analysis. Results revealed no significant differences in the latency of ABR waves I, III and V before and after 10 minutes of genuine/sham EMF exposure. Conclusion The present results suggest that, in our experimental conditions, a single 10 minute exposure of 900 MHz EMF emitted by a commercial mobile phone does not produce measurable immediate effects in the latency of auditory brainstem waves I, III and V.

  19. Threshold changes in auditory brainstem response (ABR) due to the administration of kanamycin in dogs.

    Science.gov (United States)

    Uzuka, Y; Furuta, T; Yamaoka, M; Ohnishi, T; Tsubone, H; Sugano, S

    1996-10-01

    Auditory brainstem response (ABR) is a useful method in evaluating auditory function in human. To investigate the ABR threshold is more effective than to pursue the trends in each component of ABR. In this study, tone burst sound stimuli were employed and the ABR threshold shift caused by kanamycin administration was investigated in dogs. In a series of monitoring of ABR against short-period auditory lesions, changes in the ABR waveform after intravenous administration of kanamycin were detected. These changes returned gradually and were reversible. The changes in ABR against long-period auditory function disorder were perceived by an increase in the ABR threshold. The ABR threshold shift occurred earlier in the high frequency sounds than in the lower frequency sounds. This is why amino glycoside antibiotics damage the cochlear hair cells in the basal layer and lead to the loss of hearing selectively for high frequency tones. These findings suggest that tracing of the ABR threshold by tone bursts could provide information that has a specificity for frequency in hearing tests and is a useful method in clinical veterinary medicine or/and toxicological tests.

  20. Effect of Sahaja yoga meditation on auditory evoked potentials (AEP) and visual contrast sensitivity (VCS) in epileptics.

    Science.gov (United States)

    Panjwani, U; Selvamurthy, W; Singh, S H; Gupta, H L; Mukhopadhyay, S; Thakur, L

    2000-03-01

    The effect of Sahaja yoga meditation on 32 patients with primary idiopathic epilepsy on regular and maintained antiepileptic medication was studied. The patients were randomly divided into 3 groups: group I practiced Sahaja Yoga meditation twice daily for 6 months under proper guidance; group II practiced postural exercises mimicking the meditation for the same duration; and group III was the control group. Visual Contrast Sensitivity (VCS), Auditory Evoked Potentials (AEP), Brainstem Auditory Evoked Potentials (BAEP), and Mid Latency Responses (MLR) were recorded initially (0 month) and at 3 and 6 months for each group. There was a significant improvement in VCS following meditation practice in group I participants. Na, the first prominent negative peak of MLR and Pa, the positive peak following Na did not register changes in latency. The Na-Pa amplitude of MLR also showed a significant increase. There were no significant changes in the absolute and interpeak latencies of BAEP. The reduced level of stress following meditation practice may make patients more responsive to specific stimuli. Sahaja Yoga meditation appears to bring about changes in some of the electrophysiological responses studied in epileptic patients.

  1. Neonate Auditory Brainstem Responses to CE-Chirp and CE-Chirp Octave Band Stimuli II: Versus Adult Auditory Brainstem Responses.

    Science.gov (United States)

    Cobb, Kensi M; Stuart, Andrew

    The purpose of the study was to examine the differences in auditory brainstem response (ABR) latency and amplitude indices to the CE-Chirp stimuli in neonates versus young adults as a function of stimulus level, rate, polarity, frequency and gender. Participants were 168 healthy neonates and 20 normal-hearing young adults. ABRs were obtained to air- and bone-conducted CE-Chirps and air-conducted CE-Chirp octave band stimuli. The effects of stimulus level, rate, and polarity were examined with air-conducted CE-Chirps. The effect of stimulus level was also examined with bone-conducted CE-Chirps and CE-Chirp octave band stimuli. The effect of gender was examined across all stimulus manipulations. In general, ABR wave V amplitudes were significantly larger (p 0.05). Significant differences in ABR latencies and amplitudes exist between newborns and young adults using CE-Chirp stimuli. These differences are consistent with differences to traditional click and tone burst stimuli and reflect maturational differences as a function of age. These findings continue to emphasize the importance of interpreting ABR results using age-based normative data.

  2. Neural synchrony in ventral cochlear nucleus neuron populations is not mediated by intrinsic processes but is stimulus induced: implications for auditory brainstem implants.

    Science.gov (United States)

    Shivdasani, Mohit N; Mauger, Stefan J; Rathbone, Graeme D; Paolini, Antonio G

    2009-12-01

    The aim of this investigation was to elucidate if neural synchrony forms part of the spike time-based theory for coding of sound information in the ventral cochlear nucleus (VCN) of the auditory brainstem. Previous research attempts to quantify the degree of neural synchrony at higher levels of the central auditory system have indicated that synchronized firing of neurons during presentation of an acoustic stimulus could play an important role in coding complex sound features. However, it is unknown whether this synchrony could in fact arise from the VCN as it is the first station in the central auditory pathway. Cross-correlation analysis was conducted on 499 pairs of multiunit clusters recorded in the urethane-anesthetized rat VCN in response to pure tones and combinations of two tones to determine the presence of neural synchrony. The shift predictor correlogram was used as a measure for determining the synchrony owing to the effects of the stimulus. Without subtraction of the shift predictor, over 65% of the pairs of multiunit clusters exhibited significant correlation in neural firing when the frequencies of the tones presented matched their characteristic frequencies (CFs). In addition, this stimulus-evoked neural synchrony was dependent on the physical distance between electrode sites, and the CF difference between multiunit clusters as the number of correlated pairs dropped significantly for electrode sites greater than 800 microm apart and for multiunit cluster pairs with a CF difference greater than 0.5 octaves. However, subtraction of the shift predictor correlograms from the raw correlograms resulted in no remaining correlation between all VCN pairs. These results suggest that while neural synchrony may be a feature of sound coding in the VCN, it is stimulus induced and not due to intrinsic neural interactions within the nucleus. These data provide important implications for stimulation strategies for the auditory brainstem implant, which is used to

  3. Cochlear, auditory brainstem responses in Type 1 diabetes: relationship with metabolic variables and diabetic complications.

    Science.gov (United States)

    Lasagni, A; Giordano, P; Lacilla, M; Raviolo, A; Trento, M; Camussi, E; Grassi, G; Charrier, L; Cavallo, F; Albera, R; Porta, M; Zanone, M M

    2016-09-01

    Few studies have analysed the presence of hearing abnormalities in diabetes. We assessed the presence of subclinical auditory alterations and their possible association with early vascular and neurological dysfunction in young adults with Type 1 diabetes of long duration. Thirty-one patients with Type 1 diabetes (mean age 33 ± 2.3 years, disease duration 25.7 ± 4.2 years) and 10 healthy controls underwent pure tone audiometry (PTA), distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) analyses. Associations with metabolic variables and chronic complications were explored. Compared with healthy controls, patients with diabetes had significantly higher mean hearing thresholds, although still within the normoacusic range. DPOAE intensities at medium frequencies (2.8-4 kHz) were significantly lower in patients with diabetes. In ABR, in addition to waves I, III and V, we observed the appearance of a visible wave IV in patients with diabetes compared with controls (prevalence 61% vs. 10%, P appearance was related to a prolonged I-V interval (4.40 ± 0.62 ms vs. 4.19 ± 0.58 ms, P trend towards an association between evidence of wave IV and the presence of somatic neuropathy or abnormal cardiovascular autonomic tests was observed. Young adults with long-term Type 1 diabetes have subclinical abnormalities in qualitative auditory perception, despite normal hearing thresholds, which might reflect neuropathic and/or vascular alterations. © 2015 Diabetes UK.

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

    Science.gov (United States)

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

    2010-01-01

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

  5. Implementation of a nation-wide automated auditory brainstem response hearing screening programme in neonatal intensive care units

    NARCIS (Netherlands)

    Straaten, H.L.M. van; Hille, E.T.M.; Kok, J.H.; Verkerk, P.H.; Baerts, W.; Bunkers, C.M.; Smink, E.W.A.; Elburg, R.M. van; Kleine, M.J.K. de; Ilsen, A.; Maingay-Visser, A.P.G.F.; Vries, L.S. de; Weisglas-Kuperus, N.

    2003-01-01

    Aim: As part of a future national neonatal hearing screening programme in the Netherlands, automated auditory brainstem response (AABR) hearing screening was implemented in seven neonatal intensive care units (NICUs). The objective was to evaluate key outcomes of this programme: participation rate,

  6. The Relationship between Brainstem Temporal Processing and Performance on Tests of Central Auditory Function in Children with Reading Disorders

    Science.gov (United States)

    Billiet, Cassandra R.; Bellis, Teri James

    2011-01-01

    Purpose: Studies using speech stimuli to elicit electrophysiologic responses have found approximately 30% of children with language-based learning problems demonstrate abnormal brainstem timing. Research is needed regarding how these responses relate to performance on behavioral tests of central auditory function. The purpose of the study was to…

  7. Aerial low-frequency hearing in captive and free-ranging harbour seals (Phoca vitulina) measured using auditory brainstem responses

    NARCIS (Netherlands)

    Lucke, K.; Hastie, Gordon D.; Ternes, Kerstin; McConnell, Bernie; Moss, Simon; Russell, Deborah J.F.; Weber, Heike; Janik, Vincent M.

    2016-01-01

    The hearing sensitivity of 18 free-ranging and 10 captive harbour seals (Phoca vitulina) to aerial sounds was measured in the presence of typical environmental noise through auditory brainstem response measurements. A focus was put on the comparative hearing sensitivity at low frequencies. Low-

  8. Cortical Auditory-Evoked Responses in Preterm Neonates: Revisited by Spectral and Temporal Analyses.

    Science.gov (United States)

    Kaminska, A; Delattre, V; Laschet, J; Dubois, J; Labidurie, M; Duval, A; Manresa, A; Magny, J-F; Hovhannisyan, S; Mokhtari, M; Ouss, L; Boissel, A; Hertz-Pannier, L; Sintsov, M; Minlebaev, M; Khazipov, R; Chiron, C

    2017-08-11

    Characteristic preterm EEG patterns of "Delta-brushes" (DBs) have been reported in the temporal cortex following auditory stimuli, but their spatio-temporal dynamics remains elusive. Using 32-electrode EEG recordings and co-registration of electrodes' position to 3D-MRI of age-matched neonates, we explored the cortical auditory-evoked responses (AERs) after 'click' stimuli in 30 healthy neonates aged 30-38 post-menstrual weeks (PMW). (1) We visually identified auditory-evoked DBs within AERs in all the babies between 30 and 33 PMW and a decreasing response rate afterwards. (2) The AERs showed an increase in EEG power from delta to gamma frequency bands over the middle and posterior temporal regions with higher values in quiet sleep and on the right. (3) Time-frequency and averaging analyses showed that the delta component of DBs, which negatively peaked around 550 and 750 ms over the middle and posterior temporal regions, respectively, was superimposed with fast (alpha-gamma) oscillations and corresponded to the late part of the cortical auditory-evoked potential (CAEP), a feature missed when using classical CAEP processing. As evoked DBs rate and AERs delta to alpha frequency power decreased until full term, auditory-evoked DBs are thus associated with the prenatal development of auditory processing and may suggest an early emerging hemispheric specialization. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. On the synthesis of multiple frequency tone burst stimuli for efficient high frequency auditory brainstem response.

    Science.gov (United States)

    Ellingson, Roger M; Dille, Marilyn L; Leek, Marjorie R; Fausti, Stephen A

    2008-01-01

    The development and digital waveform synthesis of a multiple-frequency tone-burst (MFTB) stimulus is presented. The stimulus is designed to improve the efficiency of monitoring high-frequency auditory-brainstem-response (ABR) hearing thresholds. The pure-tone-based, fractional-octave-bandwidth MFTB supports frequency selective ABR audiometry with a bandwidth that falls between the conventional click and single-frequency tone-burst stimuli. The MFTB is being used to identify high frequency hearing threshold change due to ototoxic medication which most generally starts at the ultra-highest hearing frequencies and progresses downwards but could be useful in general limited-bandwidth testing applications. Included is a Mathcad implementation and analysis of our MFTB synthesis technique and sample performance measurements of the MFTB stimulus configuration used in a clinical research ABR system.

  10. 'Compassionate use' protocol for auditory brainstem implantation in neurofibromatosis type 2: Early House Ear Institute experience.

    Science.gov (United States)

    Roberts, Daniel S; Slattery, William H; Chen, Brian S; Otto, Steve R; Schwartz, Marc S; Lekovic, Gregory P

    2017-01-01

    To report the preliminary outcomes of auditory brainstem implantation (ABI) under a compassionate use protocol for two ABI devices that are not approved by the US Food and Drug Administration. A retrospective review was performed of neurofibromatosis type 2 (NF2) patients who underwent microsurgery for vestibular schwannoma (VS) and placement of either the Cochlear ABI541 or Med-El Synchrony ABIs. Peri-operative and device- related complications were reviewed. Audiometric performance was also evaluated. Seven patients received either the Cochlear ABI541 (6) or the Med-El Synchrony ABI (1) after the resection of VS. No device or patient-related complications occurred to date. Surgical times and early audiological performance are similar to our previous experience with the Cochlear ABI24 device. Early experience with the Cochlear ABI541 and Med-El Synchrony ABI devices under a compassionate use protocol suggest that both devices are safe with comparable utility to the Cochlear ABI24 device.

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

    Science.gov (United States)

    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.

  12. Dynamics of infant cortical auditory evoked potentials (CAEPs) for tone and speech tokens.

    Science.gov (United States)

    Cone, Barbara; Whitaker, Richard

    2013-07-01

    Cortical auditory evoked potentials (CAEPs) to tones and speech sounds were obtained in infants to: (1) further knowledge of auditory development above the level of the brainstem during the first year of life; (2) establish CAEP input-output functions for tonal and speech stimuli as a function of stimulus level and (3) elaborate the data-base that establishes CAEP in infants tested while awake using clinically relevant stimuli, thus providing methodology that would have translation to pediatric audiological assessment. Hypotheses concerning CAEP development were that the latency and amplitude input-output functions would reflect immaturity in encoding stimulus level. In a second experiment, infants were tested with the same stimuli used to evoke the CAEPs. Thresholds for these stimuli were determined using observer-based psychophysical techniques. The hypothesis was that the behavioral thresholds would be correlated with CAEP input-output functions because of shared cortical response areas known to be active in sound detection. 36 infants, between the ages of 4 and 12 months (mean=8 months, s.d.=1.8 months) and 9 young adults (mean age 21 years) with normal hearing were tested. First, CAEPs amplitude and latency input-output functions were obtained for 4 tone bursts and 7 speech tokens. The tone bursts stimuli were 50 ms tokens of pure tones at 0.5, 1.0, 2.0 and 4.0 kHz. The speech sound tokens, /a/, /i/, /o/, /u/, /m/, /s/, and /∫/, were created from natural speech samples and were also 50 ms in duration. CAEPs were obtained for tone burst and speech token stimuli at 10 dB level decrements in descending order from 70 dB SPL. All CAEP tests were completed while the infants were awake and engaged in quiet play. For the second experiment, observer-based psychophysical methods were used to establish perceptual threshold for the same speech sound and tone tokens. Infant CAEP component latencies were prolonged by 100-150 ms in comparison to adults. CAEP latency

  13. Modeling binaural responses in the auditory brainstem to electric stimulation of the auditory nerve.

    Science.gov (United States)

    Chung, Yoojin; Delgutte, Bertrand; Colburn, H Steven

    2015-02-01

    Bilateral cochlear implants (CIs) provide improvements in sound localization and speech perception in noise over unilateral CIs. However, the benefits arise mainly from the perception of interaural level differences, while bilateral CI listeners' sensitivity to interaural time difference (ITD) is poorer than normal. To help understand this limitation, a set of ITD-sensitive neural models was developed to study binaural responses to electric stimulation. Our working hypothesis was that central auditory processing is normal with bilateral CIs so that the abnormality in the response to electric stimulation at the level of the auditory nerve fibers (ANFs) is the source of the limited ITD sensitivity. A descriptive model of ANF response to both acoustic and electric stimulation was implemented and used to drive a simplified biophysical model of neurons in the medial superior olive (MSO). The model's ITD sensitivity was found to depend strongly on the specific configurations of membrane and synaptic parameters for different stimulation rates. Specifically, stronger excitatory synaptic inputs and faster membrane responses were required for the model neurons to be ITD-sensitive at high stimulation rates, whereas weaker excitatory synaptic input and slower membrane responses were necessary at low stimulation rates, for both electric and acoustic stimulation. This finding raises the possibility of frequency-dependent differences in neural mechanisms of binaural processing; limitations in ITD sensitivity with bilateral CIs may be due to a mismatch between stimulation rate and cell parameters in ITD-sensitive neurons.

  14. [Auditory evoked potential and personality traits in chronic primary insomniacs].

    Science.gov (United States)

    Shen, Jian; Shui, Ren-de; Feng, Lei; Liu, Yu-Hong; He, Wei; Huang, Jing-Yi; Wang, Wei

    2009-05-01

    To investigate the personality traits and intensity dependence of auditory evoked potentials (AEPs) in chronic primary insomnia. Thirty-seven patients with chronic primary insomnia (insomnia group) and 44 healthy subjects (control group) were enrolled in the study. The AEPs were examined in insomnia and control groups; the personality traits were studied by Zuckerman's Sensation Seeking Scales (SSS) and Zuckerman-Kuhlman's Personality Questionnaire (ZKPQ); and the mood states by Plutchik-van Praag's Depression Inventory (PVP). The scores of neuroticism-anxiety and depression in insomnia group were significantly higher than those in control group (P<0.01); and the scores of impulsivity and aggression-hostility were also higher than those in control group (P<0.05); N1-P2 amplitude of AEP increased with stimulus intensity, which were significantly different in 70, 80, 90,100 dB (P<0.01). There were significant correlations between activity and N1 latency at 80 dB, activity and P2 latency at 100 dB (r=0.270, r=0.276, P<0.05); and between total scores of sensation seeking scale and N1-P2 amplitude (r=0.3746, r=0.35329, P<0.01) at 70 and 90 dB stimulus intensity in insomnia group. There were significant correlations among experience seeking and N1-P2 amplitude, experience seeking and slope rate (P<0.01) at 70, 80, 90, 100 dB stimulus intensity in insomnia group (r=0.539, r=0.3439, r=0.439, r=0.3278). There were significant correlations between sensation seeking of boredom susceptibility and slope rate (r=-0.282998, P<0.05) in insomnia group. There were significant correlations between thrill and adventure seeking and N1-P2 amplitude(r=0.2789, P<0.05) at 90 dB stimulus intensity in insomnia group; there were significant correlations between PVP and N1-P2 amplitude (r=-0.3434, r=-0.3158, P<0.05) at 70 dB and N1 latency at 80 dB in insomnia group. Chronic primary insomnia sufferers have higher levels of neuroticism-anxiety, depression, aggression-hostility and impulsivity

  15. Air and Bone Conduction Click and Tone-Burst Auditory Brainstem Thresholds Using Kalman Adaptive Processing in Nonsedated Normal-Hearing Infants.

    Science.gov (United States)

    Elsayed, Alaaeldin M; Hunter, Lisa L; Keefe, Douglas H; Feeney, M Patrick; Brown, David K; Meinzen-Derr, Jareen K; Baroch, Kelly; Sullivan-Mahoney, Maureen; Francis, Kara; Schaid, Leigh G

    2015-01-01

    To study normative thresholds and latencies for click and tone-burst auditory brainstem response (TB-ABR) for air and bone conduction in normal infants and those discharged from neonatal intensive care units, who passed newborn hearing screening and follow-up distortion product otoacoustic emission. An evoked potential system (Vivosonic Integrity) that incorporates Bluetooth electrical isolation and Kalman-weighted adaptive processing to improve signal to noise ratios was employed for this study. Results were compared with other published data. One hundred forty-five infants who passed two-stage hearing screening with transient-evoked otoacoustic emission or automated auditory brainstem response were assessed with clicks at 70 dB nHL and threshold TB-ABR. Tone bursts at frequencies between 500 and 4000 Hz were used for air and bone conduction auditory brainstem response testing using a specified staircase threshold search to establish threshold levels and wave V peak latencies. Median air conduction hearing thresholds using TB-ABR ranged from 0 to 20 dB nHL, depending on stimulus frequency. Median bone conduction thresholds were 10 dB nHL across all frequencies, and median air-bone gaps were 0 dB across all frequencies. There was no significant threshold difference between left and right ears and no significant relationship between thresholds and hearing loss risk factors, ethnicity, or gender. Older age was related to decreased latency for air conduction. Compared with previous studies, mean air conduction thresholds were found at slightly lower (better) levels, while bone conduction levels were better at 2000 Hz and higher at 500 Hz. Latency values were longer at 500 Hz than previous studies using other instrumentation. Sleep state did not affect air or bone conduction thresholds. This study demonstrated slightly better wave V thresholds for air conduction than previous infant studies. The differences found in the present study, while statistically significant

  16. Evaluation of brain stem auditory evoked potentials in stable patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Gupta Prem

    2008-01-01

    Full Text Available Though there are few studies addressing brainstem auditory evoked potentials (BAEP in patients with chronic obstructive pulmonary disease (COPD, subclinical BAEP abnormalities in stable COPD patients have not been studied. The present study aimed to evaluate the BAEP abnormalities in this study group. Materials and Methods : In the present study, 80 male subjects were included: COPD group comprised 40 smokers with stable COPD with no clinical neuropathy; 40 age-matched healthy volunteers served as the control group. Latencies of BAEP waves I, II, III, IV, and V, together with interpeak latencies (IPLs of I-III, I-V, and III-V, and amplitudes of waves I-Ia and V-Va were studied in both the groups to compare the BAEP abnormalities in COPD group; the latter were correlated with patient characteristics and Mini-Mental Status Examination Questionnaire (MMSEQ scores to seek any significant correlation. Results: Twenty-six (65% of the 40 COPD patients had BAEP abnormalities. We observed significantly prolonged latencies of waves I, III, V over left ear and waves III, IV, V over right ear; increased IPLs of I-V, III-V over left ear and of I-III, I-V, III-V over right side. Amplitudes of waves I-Ia and V-Va were decreased bilaterally. Over left ear, the latencies of wave I and III were significantly correlated with FEV 1 ; and amplitude of wave I-Ia, with smoking pack years. A weak positive correlation between amplitude of wave I-Ia and duration of illness; and a weak negative correlation between amplitude of wave V-Va and MMSEQ scores were seen over right side. Conclusions : We observed significant subclinical BAEP abnormalities on electrophysiological evaluation in studied stable COPD male patients having mild-to-moderate airflow obstruction.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. [Application of simultaneous auditory evoked potentials and functional magnetic resonance recordings for examination of central auditory system--preliminary results].

    Science.gov (United States)

    Milner, Rafał; Rusiniak, Mateusz; Wolak, Tomasz; Piatkowska-Janko, Ewa; Naumczyk, Patrycja; Bogorodzki, Piotr; Senderski, Andrzej; Ganc, Małgorzata; Skarzyński, Henryk

    2011-01-01

    Processing of auditory information in central nervous system bases on the series of quickly occurring neural processes that cannot be separately monitored using only the fMRI registration. Simultaneous recording of the auditory evoked potentials, characterized by good temporal resolution, and the functional magnetic resonance imaging with excellent spatial resolution allows studying higher auditory functions with precision both in time and space. was to implement the simultaneous AEP-fMRI recordings method for the investigation of information processing at different levels of central auditory system. Five healthy volunteers, aged 22-35 years, participated in the experiment. The study was performed using high-field (3T) MR scanner from Siemens and 64-channel electrophysiological system Neuroscan from Compumedics. Auditory evoked potentials generated by acoustic stimuli (standard and deviant tones) were registered using modified odd-ball procedure. Functional magnetic resonance recordings were performed using sparse acquisition paradigm. The results of electrophysiological registrations have been worked out by determining voltage distributions of AEP on skull and modeling their bioelectrical intracerebral generators (dipoles). FMRI activations were determined on the basis of deviant to standard and standard to deviant functional contrasts. Results obtained from electrophysiological studies have been integrated with functional outcomes. Morphology, amplitude, latency and voltage distribution of auditory evoked potentials (P1, N1, P2) to standard stimuli presented during simultaneous AEP-fMRI registrations were very similar to the responses obtained outside scanner room. Significant fMRI activations to standard stimuli were found mainly in the auditory cortex. Activations in these regions corresponded with N1 wave dipoles modeled based on auditory potentials generated by standard tones. Auditory evoked potentials to deviant stimuli were recorded only outside the MRI

  19. 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.

  20. Effects of aging on brainstem responses to toneburst auditory stimuli: a cross-sectional and longitudinal study in dogs.

    Science.gov (United States)

    Ter Haar, G; Venker-van Haagen, A J; van den Brom, W E; van Sluijs, F J; Smoorenburg, G F

    2008-01-01

    It is assumed that the hearing of dogs becomes impaired with advancing age, but little is known about the prevalence and electrophysiologic characteristics of presbycusis in this species. As in humans, hearing in dogs becomes impaired with aging across the entire frequency range, but primarily in the high-frequency area. This change can be assessed quantitatively by brainstem-evoked response audiometry (BERA). Three groups of 10 mixed-breed dogs with similar body weights but different mean ages were used. At the start of the study, the mean age was 1.9 years (range, 0.9-3.4) in group I, 5.7 years (3.5-7) in group II, and 12.7 years (11-14) in group III. In a cross-sectional study, the BERA audiograms obtained with toneburst stimuli were compared among the 3 groups. In a longitudinal study, changes in auditory thresholds of group II dogs were followed for 7 years. Thresholds were significantly higher in group III than in groups I and II at all frequencies tested, and higher in group II than in group I at 4 kHz. The audiograms in group II indicated a progressive increase in thresholds associated with aging starting around 8-10 years of age and most pronounced in the middle- to high-frequency region (8-32 kHz). Age-related hearing loss in these dogs started around 8-10 years of age and encompassed the entire frequency range, but started and progressed most rapidly in the middle- to high-frequency area. Its progression can be followed by BERA with frequency-specific stimulation.

  1. Auditory brainstem response changes during exposure to GSM-900 radiation: an experimental study.

    Science.gov (United States)

    Kaprana, Antigoni E; Chimona, Theognosia S; Papadakis, Chariton E; Velegrakis, Stylianos G; Vardiambasis, Ioannis O; Adamidis, Georgios; Velegrakis, George A

    2011-01-01

    The objective of the present study was to investigate the possible electrophysiological time-related changes in auditory pathway during mobile phone electromagnetic field exposure. Thirty healthy rabbits were enrolled in an experimental study of exposure to GSM-900 radiation for 60 min and auditory brainstem responses (ABRs) were recorded at regular time-intervals during exposure. The study subjects were radiated via an adjustable power and frequency radio transmitter for GSM-900 mobile phone emission simulation, designed and manufactured according to the needs of the experiment. The mean absolute latency of waves III-V showed a statistically significant delay (p < 0.05) after 60, 45 and 15 min of exposure to electromagnetic radiation of 900 MHz, respectively. Interwave latency I-III was found to be prolonged after 60 min of radiation exposure in correspondence to wave III absolute latency delay. Interwave latencies I-V and III-V were found with a statistically significant delay (p < 0.05) after 30 min of radiation. No statistically significant delay was found for the same ABR parameters in recordings from the ear contralateral to the radiation source at 60 min radiation exposure compared with baseline ABR. The ABR measurements returned to baseline recordings 24 h after the exposure to electromagnetic radiation of 900 MHz. The prolongation of interval latencies I-V and III-V indicates that exposure to electromagnetic fields emitted by mobile phone can affect the normal electrophysiological activity of the auditory system, and these findings fit the pattern of general responses to a stressor. Copyright © 2010 S. Karger AG, Basel.

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

    Directory of Open Access Journals (Sweden)

    Susan Abadi

    2016-09-01

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

  3. Auditory evoked potentials in patients with dementia of the Alzheimer type.

    Science.gov (United States)

    Grimes, A M; Grady, C L; Pikus, A

    1987-06-01

    Dementia of the Alzheimer type (DAT) disrupts the function of the central auditory nervous system as a result of temporal lobe pathology. Auditory brain stem response (ABR) and middle latency responses (MLR) were studied in a group of patients with DAT to determine whether a correlate of dementia existed in these electrophysiological potentials. Comparison of absolute and interwave latencies on ABR, and absolute latency and amplitude of the MLR in patients with DAT and normal aged controls showed no significant differences between groups for any measure. Further, no relationship with degree of dementia or temporal lobe involvement, as assessed through dichotic speech recognition studies, and auditory evoked potentials could be demonstrated. It was concluded that the temporal lobe atrophy and hypometabolism seen in DAT is not generally sufficient to disrupt the generating of ABR and MLR potentials; however, slow cortical and cognitive evoked potentials may be more sensitive to central auditory nervous system impairment in DAT.

  4. 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 wave, amplitude of I-Ia wave (p wave (P waves of BAEP in left ear before vs after MP. On comparison of right (having exposure routinely as found to be dominating ear) and left ears (not exposed to MP), before exposure to MP, IPL of IIl-V wave and amplitude of V-Va is more (wave (< 0.001) in left ear. After exposure to MP, the amplitude of V-Va was (p < 0.05) more in right ear compared to left ear. In conclusion, EMWs emitted from MP affects the auditory potential.

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

    Directory of Open Access Journals (Sweden)

    Gisiane Munaro

    2010-06-01

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

  6. Increased Evoked Potentials to Arousing Auditory Stimuli during Sleep: Implication for the Understanding of Dream Recall

    OpenAIRE

    Vallat, Raphael; Lajnef, Tarek; Eichenlaub, Jean-Baptiste; Berthomier, Christian; Jerbi, Karim; Morlet, Dominique; Ruby, Perrine M.

    2017-01-01

    High dream recallers (HR) show a larger brain reactivity to auditory stimuli during wakefulness and sleep as compared to low dream recallers (LR) and also more intra-sleep wakefulness (ISW), but no other modification of the sleep macrostructure. To further understand the possible causal link between brain responses, ISW and dream recall, we investigated the sleep microstructure of HR and LR, and tested whether the amplitude of auditory evoked potentials (AEPs) was predictive of arousing react...

  7. Neonatal Cortical Auditory Evoked Potentials Are Affected by Clinical Conditions Occurring in Early Prematurity.

    Science.gov (United States)

    Suppiej, Agnese; Cainelli, Elisa; Cappellari, Ambra; Ermani, Mario; Sartori, Stefano; Bisiacchi, Patrizia S

    2015-10-01

    Cortical auditory evoked potentials may serve as an early indicator of developmental problems in the auditory cortex. The aim of the study was to determine the effect on neonatal cortical auditory processing of clinical conditions occurring in early prematurity. Sixty-seven preterm infants born at 29 weeks mean gestational age (range, 23-34 weeks) were recorded at a mean postconception age of 35 weeks, before discharge from the third level neonatal intensive care unit. The average of 330 responses to standard 1000 Hz pure tones delivered in an oddball paradigm was recorded at frontal location. Data of 45 of 67 recruited premature infants were available for analysis. Mean amplitudes calculated from the data points of 30 milliseconds centered on P1 and N2 peaks in the waveforms of each subject were measured. The effect of perinatal clinical factors on cortical auditory evoked responses was evaluated. The amplitude of P1 component was significantly lower in infants with bronco-pulmonary dysplasia (P = 0.004) and retinopathy of prematurity (P = 0.03). The multivariate analysis, done to evaluate the relative weight of gestational age and bronco-pulmonary dysplasia and/or retinopathy of prematurity on cortical auditory evoked potentials components, showed an effect of clinical factors on P1 (P = 0.005) and of gestational age on N2 (P = 0.02). Cortical auditory processing seems to be influenced by clinical conditions complicating extremely preterm birth.

  8. 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...

  9. Effects of N-Acetylcysteine on Auditory Brainstem Response Threshold Shift in Rabbits Exposed to Noise and Carbon Monoxide

    OpenAIRE

    Seyedbagher Mortazavi; Masoud M. Kashani; Ali Khavanin; Abdolamir Alameh; Ramezan Mirzaee; Mehdi Akbari

    2010-01-01

    Problem statement: Noise Induced Hearing Loss (NIHL) is one of the most important occupational disease in worldwide. NIHL has been found to be potentiated by simultaneous Carbon monoxide (CO) exposure. Exposure to noise plus CO is common in occupational and environmental settings. Free radicals have been implicated in cochlear damage resulting from exposure to noise and due to CO hypoxia This study examined whether N-Acetylcysteine (NAC) administration cause attenuation of Auditory Brainstem ...

  10. Auditory evoked blink reflex in peripheral facial paresis.

    Science.gov (United States)

    Ayta, Semih; Sohtaoğlu, Melis; Uludüz, Derya; Uygunoğlu, Uğur; Tütüncü, Melih; Akalin, Mehmet Ali; Kiziltan, Meral E

    2015-02-01

    The auditory blink reflex (ABR) is a teleceptive reflex consisting of an early brief muscle contraction of the orbicularis oculi in response to sound stimuli. Constriction of the orbicularis oculi in response to auditory stimulation is accepted as a part of the startle reaction. The blink reflex and ABR might share a final common pathway, consisting of facial nerve nuclei and the facial nerve and may have common premotor neurons. In this study, the authors evaluated the value of the ABR in patients with peripheral facial palsy (PFP), cross-checking the results with commonly used blink reflex changes. In total, 83 subjects with PFP and 34 age-matched healthy volunteers were included. Auditory blink reflex was elicited in all control subjects and in 36 PFP cases on the paralytic sides (43.3%), whereas it was asymmetric in 30.1% of the patients. Auditory blink reflex positivity was significantly lower in PFP cases with increasing severity. Blink reflex results were largely correlated with ABR positivity. Auditory blink reflex is a useful readily elicited and sensitive test in PFP cases, providing parallel results to blink reflex and being affected by disease severity.

  11. Processing of speech temporal and spectral information by users of auditory brainstem implants and cochlear implants.

    Science.gov (United States)

    Azadpour, Mahan; McKay, Colette M

    2014-01-01

    Auditory brainstem implants (ABI) use the same processing strategy as was developed for cochlear implants (CI). However, the cochlear nucleus (CN), the stimulation site of ABIs, is anatomically and physiologically more complex than the auditory nerve and consists of neurons with differing roles in auditory processing. The aim of this study was to evaluate the hypotheses that ABI users are less able than CI users to access speech spectro-temporal information delivered by the existing strategies and that the sites stimulated by different locations of CI and ABI electrode arrays differ in encoding of temporal patterns in the stimulation. Six CI users and four ABI users of Nucleus implants with ACE processing strategy participated in this study. Closed-set perception of aCa syllables (16 consonants) and bVd words (11 vowels) was evaluated via experimental processing strategies that activated one, two, or four of the electrodes of the array in a CIS manner as well as subjects' clinical strategies. Three single-channel strategies presented the overall temporal envelope variations of the signal on a single-implant electrode located at the high-, medium-, and low-frequency regions of the array. Implantees' ability to discriminate within electrode temporal patterns of stimulation for phoneme perception and their ability to make use of spectral information presented by increased number of active electrodes were assessed in the single- and multiple-channel strategies, respectively. Overall percentages and information transmission of phonetic features were obtained for each experimental program. Phoneme perception performance of three ABI users was within the range of CI users in most of the experimental strategies and improved as the number of active electrodes increased. One ABI user performed close to chance with all the single and multiple electrode strategies. There was no significant difference between apical, basal, and middle CI electrodes in transmitting speech

  12. Cortical Evoked Potentials and Hearing Aids in Individuals with Auditory Dys-Synchrony.

    Science.gov (United States)

    Yuvaraj, Pradeep; Mannarukrishnaiah, Jayaram

    2015-12-01

    The purpose of the present study was to investigate the relationship between cortical processing of speech and benefit from hearing aids in individuals with auditory dys-synchrony. Data were collected from 38 individuals with auditory dys-synchrony. Participants were selected based on hearing thresholds, middle ear reflexes, otoacoustic emissions, and auditory brain stem responses. Cortical-evoked potentials were recorded for click and speech. Participants with auditory dys-synchrony were fitted with bilateral multichannel wide dynamic range compression hearing aids. Aided and unaided speech identification scores for 40 words were obtained for each participant. Hierarchical cluster analysis using Ward's method clearly showed four subgroups of participants with auditory dys-synchrony based on the hearing aid benefit score (aided minus unaided speech identification score). The difference in the mean aided and unaided speech identification scores was significantly different in participants with auditory dys-synchrony. However, the mean unaided speech identification scores were not significantly different between the four subgroups. The N2 amplitude and P1 latency of the speech-evoked cortical potentials were significantly different between the four subgroups formed based on hearing aid benefit scores. The results indicated that subgroups of individuals with auditory dys-synchrony who benefit from hearing aids exist. Individuals who benefitted from hearing aids showed decreased N2 amplitudes compared with those who did not. N2 amplitude is associated with greater suppression of background noise while processing speech.

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

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    Masoud Motalebi Kashani

    2012-10-01

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

  14. 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.

  15. Bottlenose dolphin (Tursiops truncatus) auditory brainstem responses to frequency-modulated "chirp" stimuli.

    Science.gov (United States)

    Finneran, James J; Mulsow, Jason; Jones, Ryan; Houser, Dorian S; Burkard, Robert F

    2017-08-01

    Previous studies have demonstrated that increasing-frequency chirp stimuli (up-chirps) can enhance human auditory brainstem response (ABR) amplitudes by compensating for temporal dispersion occurring along the cochlear partition. In this study, ABRs were measured in two bottlenose dolphins (Tursiops truncatus) in response to spectrally white clicks, up-chirps, and decreasing-frequency chirps (down-chirps). Chirp durations varied from 125 to 2000 μs. For all stimuli, frequency bandwidth was constant (10-180 kHz) and peak-equivalent sound pressure levels (peSPLs) were 115, 125, and 135 dB re 1 μPa. Up-chirps with durations less than ∼1000 μs generally increased ABR peak amplitudes compared to clicks with the same peSPL or energy flux spectral density level, while down-chirps with durations from above ∼250 to 500 μs decreased ABR amplitudes relative to clicks. The findings generally mirror those from human studies and suggest that the use of chirp stimuli may be an effective way to enhance broadband ABR amplitudes in larger marine mammals.

  16. Measuring the Advantage of Kalman-Weighted Averaging for Auditory Brainstem Response Hearing Evaluation in Infants.

    Science.gov (United States)

    Cone, Barbara; Norrix, Linda W

    2015-06-01

    The purposes of this study were to (a) measure the effects of Kalman-weighted averaging methods on auditory brainstem response (ABR) threshold, latency, and amplitude; (b) translate lab findings to the clinical setting; and (c) estimate cost savings when ABRs can be obtained in nonsedated infants. ABRs were recorded in 40 adults with normal hearing during induced motor noise conditions using the Kalman-weighted averaging method implemented on a commercial system, the Vivosonic Integrity (Vivosonic Inc., Toronto, Ontario, Canada). The device was then used to test 34 infants in awake and asleep states. The advantages of the Kalman-weighted averaging method were modeled in terms of time saved for conducting an ABR evaluation. Kalman-weighted ABR threshold estimates were 6-7 dB lower than with conventional methods during induced motor noise. When used to obtain ABRs in infants who were awake, the number of sweeps required to obtain a result was significantly greater than that required for a sleeping infant but well within the range for clinical application. The use of Kalman-weighted averaging provides a measurable advantage over conventional methods and may reduce costs for the pediatric audiology practice.

  17. 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.

  18. Correlation between auditory brainstem response and hearing prognosis in idiopathic sudden sensorineural hearing loss patients.

    Science.gov (United States)

    Lin, Hung-Che; Chou, Yu-Ching; Wang, Chih-Hung; Hung, Li-Wen; Shih, Cheng-Ping; Kang, Bor-Hwang; Yeh, Wen-Ying; Chen, Hsin-Chien

    2017-12-01

    To investigate the latency and amplitude of auditory brainstem response (ABR) and hearing prognosis in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). Patients with ISSNHL were classified into four different recovery groups. All patients' clinical and demographic features were analyzed. Two-channel ABRs were collected in response to click stimuli at 90dB nHL. ABR amplitudes for wave I and ABR latency for waves I, III, and V were analyzed. One hundred and two patients (54 men and 48 women) were included in the study. Hearing recovery was observed in 72 cases (70.6%). Waves I, III, and V latencies were significantly prolonged in the affected ears compared with the unaffected ears. A smaller wave I amplitude was found in the affected ear compared with the unaffected ear in the three recovery groups. There was a significant association between wave I latency and hearing outcome (p=0.009) with a prolonged trend from complete to slight hearing recovery group. There was a significant correlation between wave I latency and hearing outcome in patients with ISSNHL. The finding may provide diagnostic information and serve as a potential prognostic indicator in patients with ISSNHL. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Sensory gating of auditory evoked potentials in rats: Effects of repetitive stimulation and the interstimulus interval

    NARCIS (Netherlands)

    Bruin, N.M.W.J. de; Ellenbroek, B.A.; Schaijk, W.J. van; Cools, A.R.; Coenen, A.M.L.; Luijtelaar, E.L.J.M. van

    2001-01-01

    In the P50 gating or conditioning-testing (C-T) paradigm, the P50 response, a small positive midlatency (~50 ms after stimulus onset) component of the human auditory evoked potential (AEP), is reduced towards the second click (S2) as compared to the response to the first click (S1). This phenomenon

  20. Sensory gating of auditory evoked potentials in rats: effects of repetitive stimulation and the interstimulus interval.

    NARCIS (Netherlands)

    Bruin, N.M.W.J. de; Ellenbroek, B.A.; Schaijk, W.J. van; Cools, A.R.; Coenen, A.M.L.; Luijtelaar, E.L.J.M. van

    2001-01-01

    In the P50 gating or conditioning-testing (C-T) paradigm, the P50 response, a small positive midlatency ( approximately 50 ms after stimulus onset) component of the human auditory evoked potential (AEP), is reduced towards the second click (S2) as compared to the response to the first click (S1).

  1. The Analysis and Treatment of Problem Behavior Evoked by Auditory Stimulation

    Science.gov (United States)

    Devlin, Sarah; Healy, Olive; Leader, Geraldine; Reed, Phil

    2008-01-01

    The current study aimed to identify specific stimuli associated with music that served as an establishing operation (EO) for the problem behavior of a 6-year-old child with a diagnosis of autism. Specific EOs for problem behavior evoked by auditory stimulation could be identified. A differential negative reinforcement procedure was implemented for…

  2. Effects of diazepam on auditory evoked potentials of rats elicited in a ten-tone paradigm

    NARCIS (Netherlands)

    Jongsma, M.L.A.; Rijn, C.M. van; Schaijk, W.J. van; Coenen, A.M.L.; Dirksen, R.

    2000-01-01

    The effect of diazepam on sensory gating was studied in rats, by measuring diazepam effects on Auditory Evoked Potentials (AEPs) elicited in a ten-tone paradigm. Trains of 10 repetitive tone-pip stimuli were presented. Rats (n=8) received 4 mg.kg-1 diazepam s.c. or vehicle, counterbalanced over two

  3. Neural generators of the auditory evoked potential components P3a and P3b

    NARCIS (Netherlands)

    Wronka, E.; Kaiser, J.; Coenen, A.M.L.

    2012-01-01

    The aim of the present study was to define the scalp topography of the two subcomponents of the P3 component of the auditory evoked potential elicited in a three-stimulus oddball paradigm and to identify their cortical generators using the standardized low resolution electromagnetic tomography

  4. Analysis of gender based differences in auditory evoked potentials among healthy elderly population

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    Sharat Gupta

    2014-01-01

    Full Text Available Background: Influence of gender on auditory evoked potentials is contentious. Although there are quite a few studies documenting the gender as an influencing factor on auditory evoked potentials in younger subjects, but there is a lack of similar studies among elderly population. The present study was conducted to find out the pattern of gender based differences in auditory evoked potentials among healthy elderly subjects. Materials and Methods: A cross-sectional study was conducted on age matched, healthy males (n = 35 and females (n = 34, aged 50-70 years. The measures included latencies of waves I-V and interpeak latencies (IPL I-III, III-V and I-V separately for both ears. Data was analyzed statistically using Students unpaired t-test, using Statistical Package for Social Sciences software v13.0. Results: The values of all the latencies and IPL for both the ears were non-significantly higher (P > 0.05 in males as compared to females. These results may be attributed to the differences in head circumference between both the genders and to the changed hormonal milieu of sex hormones after menopause. Conclusions: Statistical insignificance of latencies among male and female elderly subjects excludes gender as an influencing factor on auditory evoked potentials in this age group.

  5. Rhythmic context influences the auditory evoked potentials of musicians and nonmusicians

    NARCIS (Netherlands)

    Jongsma, M.L.A.; Desain, P.W.M.; Honing, H.J.

    2004-01-01

    In this study, we investigated how rhythms are processed in the brain by measuring both behaviourally obtained ratings and auditory evoked potentials (AEPs) from the EEG. We presented probe beats on seven positions within a test bar. Two bars of either a duple- or triple meter rhythm preceded probe

  6. Temporal processing and long-latency auditory evoked potential in stutterers

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    Raquel Prestes

    Full Text Available Abstract Introduction: Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. Objective: To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. Methods: The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n = 20 and non-stutters (n = 21, compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Results: Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Conclusion: Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components.

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

    NARCIS (Netherlands)

    ter Haar, G.|info:eu-repo/dai/nl/304828750

    2009-01-01

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

  8. [Anesthesia with flunitrazepam/fentanyl and isoflurane/fentanyl. Unconscious perception and mid-latency auditory evoked potentials].

    Science.gov (United States)

    Schwender, D; Kaiser, A; Klasing, S; Faber-Züllig, E; Golling, W; Pöppel, E; Peter, K

    1994-05-01

    There is a high incidence of intraoperative awareness during cardiac surgery. Mid-latency auditory evoked potentials (MLAEP) reflect the primary cortical processing of auditory stimuli. In the present study, we investigated MLAEP and explicit and implicit memory for information presented during cardiac anaesthesia. PATIENTS AND METHODS. Institutional approval and informed consent was obtained in 30 patients scheduled for elective cardiac surgery. Anaesthesia was induced in group I (n = 10) with flunitrazepam/fentanyl (0.01 mg/kg) and maintained with flunitrazepam/fentanyl (1.2 mg/h). The patients in group II (n = 10) received etomidate (0.25 mg/kg) and fentanyl (0.005 mg/kg) for induction and isoflurane (0.6-1.2 vol%)/fentanyl (1.2 mg/h) for maintenance of general anaesthesia. Group III (n = 10) served as a control and patients were anaesthetized as in I or II. After sternotomy an audiotape that included an implicit memory task was presented to the patients in groups I and II. The story of Robinson Crusoe was told, and it was suggested to the patients that they remember Robinson Crusoe when asked what they associated with the word Friday 3-5 days postoperatively. Auditory evoked potentials were recorded awake and during general anaesthesia before and after the audiotape presentation on vertex (positive) and mastoids on both sides (negative). Auditory clicks were presented binaurally at 70 dBnHL at a rate of 9.3 Hz. Using the electrodiagnostic system Pathfinder I (Nicolet), 1000 successive stimulus responses were averaged over a 100 ms poststimulus interval and analyzed off-line. Latencies of the peak V, Na, Pa were measured. V belongs to the brainstem-generated potentials, which demonstrates that auditory stimuli were correctly transduced. Na, Pa are generated in the primary auditory cortex of the temporal lobe and are the electrophysiological correlate of the primary cortical processing of the auditory stimuli. RESULTS. None of the patients had an explicit memory

  9. Utility of auditory steady-state and brainstem responses in age-related hearing loss in rats.

    Science.gov (United States)

    Sanz-Fernández, Ricardo; Sánchez-Rodriguez, Carolina; Granizo, José Juan; Durio-Calero, Enrique; Martín-Sanz, Eduardo

    2015-01-01

    The results support the idea that auditory steady-state response (ASSR) is a more accurate test for studying age-related hearing loss (ARHL) in Sprague-Dawley rats. Differences in the rat middle ear may explain the variations of the click properties, with a displacement of the energy toward the 8 and 10 kHz frequencies compared with humans. The purpose of this study was to evaluate ARHL in older and younger Sprague-Dawley rats using auditory clicks and tone burst with auditory brainstem response (ABR), in addition to ASSR. This was a prospective cohort study with 50 animals divided into 5 groups based on their age in months. A total of 100 registers were elicited from each one of the 3 auditory measurements systems in an electrically shielded, double-walled, sound-treated cabin. Nine frequencies, from 0.5 to 16 kHz were analyzed with the auditory steady-state response and compared with the results elicited by the clicks and tone-burst ABR. Comparisons between the different frequencies showed lower thresholds in those frequencies below 2 kHz, independently of their age in months. The ARHL was detected by each one of the three auditory measurement systems, but with lower thresholds with the ASSR test. Finally, auditory clicks showed better correlations with 8 and 10 kHz elicited by ASSR, which was different to what was expected, based on human studies.

  10. Audiograms of three subterranean rodent species (gen. Fukomys) determined by auditory brainstem responses reveal extremely low high-frequency cut-offs.

    Science.gov (United States)

    Gerhardt, Patricia; Henning, Yoshiyuki; Begall, Sabine; Malkemper, E Pascal

    2017-10-12

    Life underground has shaped the auditory sense of subterranean mammals, shifting their hearing range to low frequencies. Mole-rats of the genus Fukomys have, however, been suggested to hear up to 18.5 kHz, unusually high for a subterranean rodent. We present audiograms of three mole-rat species, Fukomys anselli, Fukomys micklemi and the giant mole-rat Fukomys mechowii, based on evoked auditory brainstem potentials. All species showed low sensitivity and restricted hearing ranges at 60 dB SPL extending from 125 Hz to 4 kHz (5 octaves) with most sensitive hearing between 0.8 kHz and 1.4 kHz. The high frequency cut-offs are the lowest found in mammals to date. In contrast to predictions from middle ear morphology, F. mechowii did not show higher sensitivity in the low frequency range than F. anselli These data suggest that the hearing range of Fukomys mole-rats is highly restricted to low frequencies and similar to other subterranean mammals. © 2017. Published by The Company of Biologists Ltd.

  11. Auditory evoked fields elicited by spectral, temporal, and spectral-temporal changes in human cerebral cortex

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    Hidehiko eOkamoto

    2012-05-01

    Full Text Available Natural sounds contain complex spectral components, which are temporally modulated as time-varying signals. Recent studies have suggested that the auditory system encodes spectral and temporal sound information differently. However, it remains unresolved how the human brain processes sounds containing both spectral and temporal changes. In the present study, we investigated human auditory evoked responses elicited by spectral, temporal, and spectral-temporal sound changes by means of magnetoencephalography (MEG. The auditory evoked responses elicited by the spectral-temporal change were very similar to those elicited by the spectral change, but those elicited by the temporal change were delayed by 30 – 50 ms and differed from the others in morphology. The results suggest that human brain responses corresponding to spectral sound changes precede those corresponding to temporal sound changes, even when the spectral and temporal changes occur simultaneously.

  12. Long latency auditory evoked potentials in children with cochlear implants: systematic review.

    Science.gov (United States)

    Silva, Liliane Aparecida Fagundes; Couto, Maria Inês Vieira; Matas, Carla Gentile; Carvalho, Ana Claudia Martinho de

    2013-11-25

    The aim of this study was to analyze the findings on Cortical Auditory Evoked Potentials in children with cochlear implant through a systematic literature review. After formulation of research question and search of studies in four data bases with the following descriptors: electrophysiology (eletrofisiologia), cochlear implantation (implante coclear), child (criança), neuronal plasticity (plasticidade neuronal) and audiology (audiologia), were selected articles (original and complete) published between 2002 and 2013 in Brazilian Portuguese or English. A total of 208 studies were found; however, only 13 contemplated the established criteria and were further analyzed; was made data extraction for analysis of methodology and content of the studies. The results described suggest rapid changes in P1 component of Cortical Auditory Evoked Potentials in children with cochlear implants. Although there are few studies on the theme, cochlear implant has been shown to produce effective changes in central auditory path ways especially in children implanted before 3 years and 6 months of age.

  13. Cortical Auditory-Evoked Potential and Behavioral Evidence for Differences in Auditory Processing between Good and Poor Readers.

    Science.gov (United States)

    Barker, Matthew D; Kuruvilla-Mathew, Abin; Purdy, Suzanne C

    2017-06-01

    The relationship between auditory processing (AP) and reading is thought to be significant; however our understanding of this relationship is somewhat limited. Previous studies have investigated the relation between certain electrophysiological and behavioral measures of AP and reading abilities in children. This study attempts to further understand that relation. Differences in AP between good and poor readers were investigated using electrophysiological and behavioral measures. Thirty-two children (15 female) aged 9-11 yr were placed in either a good reader group or poor reader group, based on the scores of a nationally normed reading test in New Zealand. Children were initially tested using an automated behavioral measuring system that runs through a tablet computer known as "Feather Squadron." Following the administration of Feather Squadron, cortical auditory-evoked potentials (CAEPs) were recorded using a speech stimulus (/m/) with the HEARLab(®) Cortical Auditory Evoked Potential Analyzer. The children were evaluated on eight subsections of the Feather Squadron, and CAEP waveform peaks were visually identified and averaged. Separate Kruskal-Wallis analyses were performed for the behavioral and electrophysiological variables, with group (good versus poor readers) serving as the between-group independent variable and scores from the Feather Squadron AP tasks as well as CAEP latencies and amplitudes as dependent variables. After the children's AP status was determined, the entire group was further divided into three groups: typically developing, auditory processing disorder + reading difficulty (APD + RD), and RDs only. Statistical analyses were repeated for these subgroups. Poorer readers showed significantly worse scores than the good readers for the Tonal Pattern 1, Tonal Pattern 2, and Word Double Dichotic Right tasks. CAEP differences observed across groups indicated comorbid effects of RD and AP difficulties. N2 amplitude was significantly smaller for

  14. Is the auditory evoked P2 response a biomarker of learning?

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    Kelly eTremblay

    2014-02-01

    Full Text Available Even though auditory training exercises for humans have been shown to improve certain perceptual skills of individuals with and without hearing loss, there is a lack of knowledge pertaining to which aspects of training are responsible for the perceptual gains, and which aspects of perception are changed. To better define how auditory training impacts brain and behavior, electroencephalography and magnetoencephalography have been used to determine the time course and coincidence of cortical modulations associated with different types of training. Here we focus on P1-N1-P2 auditory evoked responses (AEP, as there are consistent reports of gains in P2 amplitude following various types of auditory training experiences; including music and speech-sound training. The purpose of this experiment was to determine if the auditory evoked P2 response is a biomarker of learning. To do this, we taught native English speakers to identify a new pre-voiced temporal cue that is not used phonemically in the English language so that coinciding changes in evoked neural activity could be characterized. To differentiate possible effects of repeated stimulus exposure and a button-pushing task from learning itself, we examined modulations in brain activity in a group of participants who learned to identify the pre-voicing contrast and compared it to participants, matched in time, and stimulus exposure, that did not. The main finding was that the amplitude of the P2 auditory evoked response increased across repeated EEG sessions for all groups, regardless of any change in perceptual performance. What’s more, these effects were retained for months. Changes in P2 amplitude were attributed to changes in neural activity associated with the acquisition process and not the learned outcome itself. A further finding was the expression of a late negativity (LN wave 600-900 ms post-stimulus onset, post-training, exclusively for the group that learned to identify the pre

  15. Is the auditory evoked P2 response a biomarker of learning?

    Science.gov (United States)

    Tremblay, Kelly L.; Ross, Bernhard; Inoue, Kayo; McClannahan, Katrina; Collet, Gregory

    2014-01-01

    Even though auditory training exercises for humans have been shown to improve certain perceptual skills of individuals with and without hearing loss, there is a lack of knowledge pertaining to which aspects of training are responsible for the perceptual gains, and which aspects of perception are changed. To better define how auditory training impacts brain and behavior, electroencephalography (EEG) and magnetoencephalography (MEG) have been used to determine the time course and coincidence of cortical modulations associated with different types of training. Here we focus on P1-N1-P2 auditory evoked responses (AEP), as there are consistent reports of gains in P2 amplitude following various types of auditory training experiences; including music and speech-sound training. The purpose of this experiment was to determine if the auditory evoked P2 response is a biomarker of learning. To do this, we taught native English speakers to identify a new pre-voiced temporal cue that is not used phonemically in the English language so that coinciding changes in evoked neural activity could be characterized. To differentiate possible effects of repeated stimulus exposure and a button-pushing task from learning itself, we examined modulations in brain activity in a group of participants who learned to identify the pre-voicing contrast and compared it to participants, matched in time, and stimulus exposure, that did not. The main finding was that the amplitude of the P2 auditory evoked response increased across repeated EEG sessions for all groups, regardless of any change in perceptual performance. What’s more, these effects are retained for months. Changes in P2 amplitude were attributed to changes in neural activity associated with the acquisition process and not the learned outcome itself. A further finding was the expression of a late negativity (LN) wave 600–900 ms post-stimulus onset, post-training exclusively for the group that learned to identify the pre

  16. In-air hearing of a diving duck: A comparison of psychoacoustic and auditory brainstem response thresholds

    Science.gov (United States)

    Crowell, Sara E.; Wells-Berlin, Alicia M.; Therrien, Ronald E.; Yannuzzi, Sally E.; Carr, Catherine E.

    2016-01-01

    Auditory sensitivity was measured in a species of diving duck that is not often kept in captivity, the lesser scaup. Behavioral (psychoacoustics) and electrophysiological [the auditory brainstem response (ABR)] methods were used to measure in-air auditory sensitivity, and the resulting audiograms were compared. Both approaches yielded audiograms with similar U-shapes and regions of greatest sensitivity (2000−3000 Hz). However, ABR thresholds were higher than psychoacoustic thresholds at all frequencies. This difference was least at the highest frequency tested using both methods (5700 Hz) and greatest at 1000 Hz, where the ABR threshold was 26.8 dB higher than the behavioral measure of threshold. This difference is commonly reported in studies involving many different species. These results highlight the usefulness of each method, depending on the testing conditions and availability of the animals.

  17. Sound-Evoked Activity Influences Myelination of Brainstem Axons in the Trapezoid Body.

    Science.gov (United States)

    Sinclair, James L; Fischl, Matthew J; Alexandrova, Olga; Heβ, Martin; Grothe, Benedikt; Leibold, Christian; Kopp-Scheinpflug, Conny

    2017-08-23

    Plasticity of myelination represents a mechanism to tune the flow of information by balancing functional requirements with metabolic and spatial constraints. The auditory system is heavily myelinated and operates at the upper limits of action potential generation frequency and speed observed in the mammalian CNS. This study aimed to characterize the development of myelin within the trapezoid body, a central auditory fiber tract, and determine the influence sensory experience has on this process in mice of both sexes. We find that in vitro conduction speed doubles following hearing onset and the ability to support high-frequency firing increases concurrently. Also in this time, the diameter of trapezoid body axons and the thickness of myelin double, reaching mature-like thickness between 25 and 35 d of age. Earplugs were used to induce ∼50 dB elevation in auditory thresholds. If introduced at hearing onset, trapezoid body fibers developed thinner axons and myelin than age-matched controls. If plugged during adulthood, the thickest trapezoid body fibers also showed a decrease in myelin. These data demonstrate the need for sensory activity in both development and maintenance of myelin and have important implications in the study of myelin plasticity and how this could relate to sensorineural hearing loss following peripheral impairment.SIGNIFICANCE STATEMENT The auditory system has many mechanisms to maximize the dynamic range of its afferent fibers, which operate at the physiological limit of action potential generation, precision, and speed. In this study we demonstrate for the first time that changes in peripheral activity modifies the thickness of myelin in sensory neurons, not only in development but also in mature animals. The current study suggests that changes in CNS myelination occur as a downstream mechanism following peripheral deficit. Given the required submillisecond temporal precision for binaural auditory processing, reduced myelination might augment

  18. Brain stem auditory evoked responses in human infants and adults

    Science.gov (United States)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  19. Localization of Kv1.3 channels in presynaptic terminals of brainstem auditory neurons.

    Science.gov (United States)

    Gazula, Valeswara-Rao; Strumbos, John G; Mei, Xiaofeng; Chen, Haijun; Rahner, Christoph; Kaczmarek, Leonard K

    2010-08-15

    Elimination of the Kv1.3 voltage-dependent potassium channel gene produces striking changes in the function of the olfactory bulb, raising the possibility that this channel also influences other sensory systems. We have examined the cellular and subcellular localization of Kv1.3 in the medial nucleus of the trapezoid body (MNTB) in the auditory brainstem, a nucleus in which neurons fire at high rates with high temporal precision. A clear gradient of Kv1.3 immunostaining along the lateral to medial tonotopic axis of the MNTB was detected. Highest levels were found in the lateral region of the MNTB, which corresponds to neurons that respond selectively to low-frequency auditory stimuli. Previous studies have demonstrated that MNTB neurons and their afferent inputs from the cochlear nucleus express three other members of the Kv1 family, Kv1.1, Kv1.2, and Kv1.6. Nevertheless, confocal microscopy of MNTB sections coimmunostained for Kv1.3 with these subunits revealed that the distribution of Kv1.3 differed significantly from other Kv1 family subunits. In particular, no axonal staining of Kv1.3 was detected, and most prominent labeling was in structures surrounding the somata of the principal neurons, suggesting specific localization to the large calyx of Held presynaptic endings that envelop the principal cells. The presence of Kv1.3 in presynaptic terminals was confirmed by coimmunolocalization with the synaptic markers synaptophysin, syntaxin, and synaptotagmin and by immunogold electron microscopy. Kv1.3 immunogold particles in the terminals were arrayed along the plasma membrane and on internal vesicular structures. To confirm these patterns of staining, we carried out immunolabeling on sections from Kv1.3(-/-) mice. No immunoreactivity could be detected in Kv1.3(-/-) mice either at the light level or in immunogold experiments. The finding of a tonotopic gradient in presynaptic terminals suggests that Kv1.3 may regulate neurotransmitter release differentially in

  20. Resurgent sodium current promotes action potential firing in the avian auditory brainstem.

    Science.gov (United States)

    Hong, Hui; Lu, Ting; Wang, Xiaoyu; Wang, Yuan; Sanchez, Jason Tait

    2017-11-28

    Auditory brainstem neurons are functionally primed to fire action potentials (APs) at markedly high-rates in order to rapidly encode acoustic information of sound. This specialization is critical for survival and the comprehension of behaviourally relevant communication functions, including sound localization and understanding speech in noise. Here, we investigated underlying ion channel mechanisms essential for high-rate AP firing in neurons of the chicken nucleus magnocellularis (NM) - the avian analog of bushy cells of the mammalian anteroventral cochlear nucleus. In addition to the established function of high-voltage activated potassium channels, we found that resurgent sodium current (INaR ) plays a role in regulating rapid firing activity of late-developing (embryonic [E] days 19-21) NM neurons. INaR of late-developing NM neurons showed similar properties with mammalian neurons in that its unique mechanism of an "open channel block state" facilitated the recovery and increased the availability of sodium (NaV ) channels after depolarization. Using a computational model of NM neurons, we demonstrated that removal of INaR reduced high-rate AP firing. We found weak INaR during a prehearing period (E11-12), which transformed to resemble late-developing INaR properties around hearing onset (E14-16). Anatomically, we detected strong NaV 1.6 expression near maturation, which became increasingly less distinct at hearing onset and prehearing periods, suggesting that multiple NaV channel subtypes may contribute to INaR during development. We conclude that INaR plays an important role in regulating rapid AP firing for NM neurons, a property that may be evolutionarily conserved for functions related to similar avian and mammalian hearing. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. The pattern of Fos expression in the rat auditory brainstem changes with the temporal structure of binaural electrical intracochlear stimulation.

    Science.gov (United States)

    Jakob, Till F; Döring, Ulrike; Illing, Robert-Benjamin

    2015-04-01

    The immediate-early-gene c-fos with its protein product Fos has been used as a powerful tool to investigate neuronal activity and plasticity following sensory stimulation. Fos combines with Jun, another IEG product, to form the dimeric transcription factor activator protein 1 (AP-1) which has been implied in a variety of cellular functions like neuronal plasticity, apoptosis, and regeneration. The intracellular emergence of Fos indicates a functional state of nerve cells directed towards molecular and morphological changes. The central auditory system is construed to detect stimulus intensity, spectral composition, and binaural balance through neurons organized in a complex network of ascending, descending and commissural pathways. Here we compare monaural and binaural electrical intracochlear stimulation (EIS) in normal hearing and early postnatally deafened rats. Binaural stimulation was done either synchronously or asynchronously. The auditory brainstem of hearing and deaf rats responds differently, with a dramatically increasing Fos expression in the deaf group so as if the network had no pre-orientation for how to organize sensory activity. Binaural EIS does not result in a trivial sum of 2 independent monaural EIS, as asynchronous stimulation invokes stronger Fos activation compared to synchronous stimulation almost everywhere in the auditory brainstem. The differential response to synchronicity of the stimulation puts emphasis on the importance of the temporal structure of EIS with respect to its potential for changing brain structure and brain function in stimulus-specific ways. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Wideband Absorbance Outcomes in Newborns: A Comparison With High-Frequency Tympanometry, Automated Brainstem Response, and Transient Evoked and Distortion Product Otoacoustic Emissions.

    Science.gov (United States)

    Aithal, Sreedevi; Kei, Joseph; Driscoll, Carlie; Khan, Asaduzzaman; Swanston, Andrew

    2015-01-01

    The purpose of this study was to evaluate the test performance of wideband absorbance (WBA) in terms of its ability to predict the outer and middle ear status as determined by nine reference standards. Automated auditory brainstem response (AABR), high-frequency (1000 Hz) tympanometry (HFT), transient evoked otoacoustic emission (TEOAE), and distortion product otoacoustic emission (DPOAE) tests were performed on 298 ears (144 right, 154 left) of 192 (108 males, 84 females) neonates with a mean age of 43.7 hours (SD = 21.3, range = 8.3 to 152.2 hr). WBA was measured from 0.25 to 8 kHz using clicks under ambient pressure conditions. Test performance of WBA was assessed in terms of its ability to identify conductive conditions in neonates when compared with nine reference standards (including four single tests and five test batteries) using the receiver operating characteristic analysis. The test performance of WBA against the test battery reference standards was better than that against single test reference standards. The area under the receiver operating characteristic curve reached a high value of 0.78 for HFT + TEOAE + DPOAE and AABR + TEOAE + DPOAE reference standards. Within the ears that passed each of the reference standards, there were no significant differences in WBA. However, for the ears that failed each of the test standards, there were significant differences in WBA. The region between 1 and 4 kHz provided the best discriminability to evaluate the conductive status compared with other frequencies. WBA is a desirable measure of conductive conditions in newborns due to its high performance in classifying ears with conductive loss as determined by the best performing surrogate gold standards (HFT + TEOAE + DPOAE and AABR + TEOAE + DPOAE).

  3. Quantifying attentional modulation of auditory-evoked cortical responses from single-trial electroencephalography

    Directory of Open Access Journals (Sweden)

    Inyong eChoi

    2013-04-01

    Full Text Available Selective auditory attention is essential for human listeners to be able to communicate in multi-source environments. Selective attention is known to modulate the neural representation of the auditory scene, boosting the representation of a target sound relative to the background, but the strength of this modulation, and the mechanisms contributing to it, are not well understood. Here, listeners performed a behavioral experiment demanding sustained, focused spatial auditory attention while we measured cortical responses using electroencephalography (EEG. We presented three concurrent melodic streams; listeners were asked to attend and analyze the melodic contour of one of the streams, randomly selected from trial to trial. In a control task, listeners heard the same sound mixtures, but performed the contour judgment task on a series of visual arrows, ignoring all auditory streams. We found that the cortical responses could be fit as weighted sum of event-related potentials evoked by the stimulus onsets in the competing streams. The weighting to a given stream was roughly 10 dB higher when it was attended compared to when another auditory stream was attended; during the visual task, the auditory gains were intermediate. We then used a template-matching classification scheme to classify single-trial EEG results. We found that in all subjects, we could determine which stream the subject was attending significantly better than by chance. By directly quantifying the effect of selective attention on auditory cortical responses, these results reveal that focused auditory attention both suppresses the response to an unattended stream and enhances the response to an attended stream. The single-trial classification results add to the growing body of literature suggesting that auditory attentional modulation is sufficiently robust that it could be used as a control mechanism in brain-computer interfaces.

  4. The roles of superficial amygdala and auditory cortex in music-evoked fear and joy.

    Science.gov (United States)

    Koelsch, Stefan; Skouras, Stavros; Fritz, Thomas; Herrera, Perfecto; Bonhage, Corinna; Küssner, Mats B; Jacobs, Arthur M

    2013-11-01

    This study investigates neural correlates of music-evoked fear and joy with fMRI. Studies on neural correlates of music-evoked fear are scant, and there are only a few studies on neural correlates of joy in general. Eighteen individuals listened to excerpts of fear-evoking, joy-evoking, as well as neutral music and rated their own emotional state in terms of valence, arousal, fear, and joy. Results show that BOLD signal intensity increased during joy, and decreased during fear (compared to the neutral condition) in bilateral auditory cortex (AC) and bilateral superficial amygdala (SF). In the right primary somatosensory cortex (area 3b) BOLD signals increased during exposure to fear-evoking music. While emotion-specific activity in AC increased with increasing duration of each trial, SF responded phasically in the beginning of the stimulus, and then SF activity declined. Psychophysiological Interaction (PPI) analysis revealed extensive emotion-specific functional connectivity of AC with insula, cingulate cortex, as well as with visual, and parietal attentional structures. These findings show that the auditory cortex functions as a central hub of an affective-attentional network that is more extensive than previously believed. PPI analyses also showed functional connectivity of SF with AC during the joy condition, taken to reflect that SF is sensitive to social signals with positive valence. During fear music, SF showed functional connectivity with visual cortex and area 7 of the superior parietal lobule, taken to reflect increased visual alertness and an involuntary shift of attention during the perception of auditory signals of danger. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. The investigation of cortical auditory evoked potentials responses in young adults having musical education.

    Science.gov (United States)

    Polat, Zahra; Ataş, Ahmet

    2014-12-01

    In the literature, music education has been shown to enhance auditory perception for children and young adults. When compared to young adult non-musicians, young adult musicians demonstrate increased auditory processing, and enhanced sensitivity to acoustic changes. The evoked response potentials associated with the interpretation of sound are enhanced in musicians. Studies show that training also changes sound perception and cortical responses. The earlier training appears to lead to larger changes in the auditory cortex. Most cortical studies in the literature have used pure tones or musical instrument sounds as stimuli signals. The aim of those studies was to investigate whether musical education would enhance auditory cortical responses when speech signals were used. In this study, the speech sounds extracted from running speech were used as sound stimuli. Non-randomized controlled study. The experimental group consists of young adults up to 21 years-old, all with a minimum of 4 years of musical education. The control group was selected from young adults of the same age without any musical education. The experiments were conducted by using a cortical evoked potential analyser and /m/, /t/ /g/ sound stimulation at the level of 65 dB SPL. In this study, P1 / N1 / P2 amplitude and latency values were measured. Significant differences were found in the amplitude values of P1 and P2 (p0.05). The results obtained in our study indicate that musical experience has an effect on the nervous system and this can be seen in cortical auditory evoked potentials recorded when the subjects hear speech.

  6. Contralateral white noise attenuates 40-Hz auditory steady-state fields but not N100m in auditory evoked fields.

    Science.gov (United States)

    Kawase, Tetsuaki; Maki, Atsuko; Kanno, Akitake; Nakasato, Nobukazu; Sato, Mika; Kobayashi, Toshimitsu

    2012-01-16

    The different response characteristics of the different auditory cortical responses under conventional central masking conditions were examined by comparing the effects of contralateral white noise on the cortical component of 40-Hz auditory steady state fields (ASSFs) and the N100 m component in auditory evoked fields (AEFs) for tone bursts using a helmet-shaped magnetoencephalography system in 8 healthy volunteers (7 males, mean age 32.6 years). The ASSFs were elicited by monaural 1000 Hz amplitude modulation tones at 80 dB SPL, with the amplitude modulated at 39 Hz. The AEFs were elicited by monaural 1000 Hz tone bursts of 60 ms duration (rise and fall times of 10 ms, plateau time of 40 ms) at 80 dB SPL. The results indicated that continuous white noise at 70 dB SPL presented to the contralateral ear did not suppress the N100 m response in either hemisphere, but significantly reduced the amplitude of the 40-Hz ASSF in both hemispheres with asymmetry in that suppression of the 40-Hz ASSF was greater in the right hemisphere. Different effects of contralateral white noise on these two responses may reflect different functional auditory processes in the cortices. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. VOICED AND UNVOICED SEPARATION IN SPEECH AUDITORY BRAINSTEM RESPONSES OF HUMAN SUBJECTS USING ZERO CROSSING RATE (ZCR) AND ENERGY OF THE SPEECH SIGNAL

    OpenAIRE

    Ranganadh Narayanam

    2017-01-01

    In speech signals two activities - voiced & unvoiced - are prominently observed, in both the cases of “production speech” from mouth, and “hearing speech” passed through ears-brainstem-and brain. These speech signals are broadly categorized into these two regions: Voiced- nearly periodic in nature; Unvoiced – random noise like in nature. For many speech applications it is most important to distinguish between Voiced and Unvoiced speech. We have collected Speech Auditory Brainstem Responses (A...

  8. Sensory gating revisited: relation between brain oscillations and auditory evoked potentials in schizophrenia.

    Science.gov (United States)

    Brockhaus-Dumke, Anke; Mueller, Ralf; Faigle, Ulrich; Klosterkoetter, Joachim

    2008-02-01

    Disturbances of auditory information processing have repeatedly been shown in schizophrenia. To contribute to a better understanding of the neurophysiological underpinnings of habituation in auditory processing and its disturbance in schizophrenia we used three different approaches to analyze auditory evoked responses, namely phase-locking (PL) analyses, single trial amplitudes, and averaged event-related potentials (P50 and N100). Given that brain oscillations reflect the neuronal correlates of information processing we hypothesized that PL and amplitudes reflect even more essential parts of auditory processing than the averaged ERP responses. In 32 schizophrenia patients and 32 matched controls EEG was continuously recorded using an auditory paired click paradigm. PL of the lower frequency bands (alpha and theta) was significantly reduced in patients whereas no significant differences were present in higher frequencies (gamma and beta). Alpha and theta PL and amplitudes showed a marked increase after the first click and to a minor degree after the second one. This habituation was more prominent in controls whereas in schizophrenia patients the response to both clicks differed only slightly. N100 suppression was significantly reduced in schizophrenia patients whereas no group differences were present with respect to the P50. This corresponded to the finding that gamma mostly contributed to the prediction of the P50 response and theta mostly to the N100 response. Our data showed that analyzing phase and amplitude in single trials provides more information on auditory information processing and reflects differences between schizophrenia patients and controls better than analyzing the averaged ERP responses.

  9. Diminished N1 auditory evoked potentials to oddball stimuli in misophonia patients

    Directory of Open Access Journals (Sweden)

    Arjan eSchröder

    2014-04-01

    Full Text Available Misophonia (hatred of sound is a newly defined psychiatric condition in which ordinary human sounds, such as breathing and eating, trigger impulsive aggression. In the current study we investigated if a dysfunction in the brain’s early auditory processing system could be present in misophonia. We screened 20 patients with misophonia with the diagnostic criteria for misophonia, and 14 matched healthy controls without misophonia, and investigated any potential deficits in auditory processing of misophonia patients using auditory event-related potentials (ERPs during an oddball task.Subjects watched a neutral silent movie while being presented a regular frequency of beep sounds in which oddball tones of 250 Hz and 4000 Hz were randomly embedded in a stream of repeated 1000 Hz standard tones. We examined the P1, N1 and P2 components locked to the onset of the tones.For misophonia patients, the N1 peak evoked by the oddball tones had a smaller mean peak amplitude than the control group. However, no significant differences were found in P1 and P2 components evoked by the oddball tones. There were no significant differences between the misophonia patients and their controls in any of the ERP components to the standard tones.The diminished N1 component to oddball tones in misophonia patients suggests an underlying neurobiological deficit in misophonia patients. This reduction might reflect a basic impairment in auditory processing in misophonia patients.

  10. Late auditory event-related evoked potential (P300) in Down's syndrome patients.

    Science.gov (United States)

    César, Carla Patrícia Hernandez Alves Ribeiro; Caovilla, Heloisa Helena; Munhoz, Mário Sérgio Lei; Ganança, Maurício Malavasi

    2010-01-01

    Down syndrome is caused by a trisomy of chromosome 21 and is associated with central auditory processing deficit, learning disability and, probably, early-onset Alzheimer's disease. To evaluate the latencies and amplitudes of evoked late auditory potential related to P300 events and their changes in young adults with Down's syndrome. Prospective case study. P300 test latency and amplitudes were evaluated in 17 individuals with Down's syndrome and 34 healthy individuals. RESULTS The P300 latency (N1, P2, N2 and P3) was longer and the N2-P3 amplitude was lower in individuals with Down syndrome when compared to those in the control group. In young adults with Down syndrome, N1, P2, N2 and P3 latencies of late auditory evoked potential related to P300 events were prolonged, and N2 - P3 amplitudes were significantly reduced, suggesting integration impairment between the auditory association area and cortical and subcortical areas of the central nervous system.

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

    Science.gov (United States)

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

    2017-08-01

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

  12. Primary Generators of Visually Evoked Field Potentials Recorded in the Macaque Auditory Cortex.

    Science.gov (United States)

    Kajikawa, Yoshinao; Smiley, John F; Schroeder, Charles E

    2017-10-18

    Prior studies have reported "local" field potential (LFP) responses to faces in the macaque auditory cortex and have suggested that such face-LFPs may be substrates of audiovisual integration. However, although field potentials (FPs) may reflect the synaptic currents of neurons near the recording electrode, due to the use of a distant reference electrode, they often reflect those of synaptic activity occurring in distant sites as well. Thus, FP recordings within a given brain region (e.g., auditory cortex) may be "contaminated" by activity generated elsewhere in the brain. To determine whether face responses are indeed generated within macaque auditory cortex, we recorded FPs and concomitant multiunit activity with linear array multielectrodes across auditory cortex in three macaques (one female), and applied current source density (CSD) analysis to the laminar FP profile. CSD analysis revealed no appreciable local generator contribution to the visual FP in auditory cortex, although we did note an increase in the amplitude of visual FP with cortical depth, suggesting that their generators are located below auditory cortex. In the underlying inferotemporal cortex, we found polarity inversions of the main visual FP components accompanied by robust CSD responses and large-amplitude multiunit activity. These results indicate that face-evoked FP responses in auditory cortex are not generated locally but are volume-conducted from other face-responsive regions. In broader terms, our results underscore the caution that, unless far-field contamination is removed, LFPs in general may reflect such "far-field" activity, in addition to, or in absence of, local synaptic responses.SIGNIFICANCE STATEMENT Field potentials (FPs) can index neuronal population activity that is not evident in action potentials. However, due to volume conduction, FPs may reflect activity in distant neurons superimposed upon that of neurons close to the recording electrode. This is problematic as the

  13. Effects of single cycle binaural beat duration on auditory evoked potentials.

    Science.gov (United States)

    Mihajloski, Todor; Bohorquez, Jorge; Özdamar, Özcan

    2014-01-01

    Binaural beat (BB) illusions are experienced as continuous central pulsations when two sounds with slightly different frequencies are delivered to each ear. It has been shown that steady-state auditory evoked potentials (AEPs) to BBs can be captured and investigated. The authors recently developed a new method of evoking transient AEPs to binaural beats using frequency modulated stimuli. This methodology was able to create single BBs in predetermined intervals with varying carrier frequencies. This study examines the effects of the BB duration and the frequency modulating component of the stimulus on the binaural beats and their evoked potentials. Normal hearing subjects were tested with a set of four durations (25, 50, 100, and 200 ms) with two stimulation configurations, binaural dichotic (binaural beats) and diotic (frequency modulation). The results obtained from the study showed that out of the given durations, the 100 ms beat, was capable of evoking the largest amplitude responses. The frequency modulation effect showed a decrease in peak amplitudes with increasing beat duration until their complete disappearance at 200 ms. Even though, at 200 ms, the frequency modulation effects were not present, the binaural beats were still perceived and captured as evoked potentials.

  14. Speaking modifies voice-evoked activity in the human auditory cortex.

    Science.gov (United States)

    Curio, G; Neuloh, G; Numminen, J; Jousmäki, V; Hari, R

    2000-04-01

    The voice we most often hear is our own, and proper interaction between speaking and hearing is essential for both acquisition and performance of spoken language. Disturbed audiovocal interactions have been implicated in aphasia, stuttering, and schizophrenic voice hallucinations, but paradigms for a noninvasive assessment of auditory self-monitoring of speaking and its possible dysfunctions are rare. Using magnetoencephalograpy we show here that self-uttered syllables transiently activate the speaker's auditory cortex around 100 ms after voice onset. These phasic responses were delayed by 11 ms in the speech-dominant left hemisphere relative to the right, whereas during listening to a replay of the same utterances the response latencies were symmetric. Moreover, the auditory cortices did not react to rare vowel changes interspersed randomly within a series of repetitively spoken vowels, in contrast to regular change-related responses evoked 100-200 ms after replayed rare vowels. Thus, speaking primes the human auditory cortex at a millisecond time scale, dampening and delaying reactions to self-produced "expected" sounds, more prominently in the speech-dominant hemisphere. Such motor-to-sensory priming of early auditory cortex responses during voicing constitutes one element of speech self-monitoring that could be compromised in central speech disorders.

  15. Effects of sequential streaming on auditory masking using psychoacoustics and auditory evoked potentials.

    Science.gov (United States)

    Verhey, Jesko L; Ernst, Stephan M A; Yasin, Ifat

    2012-03-01

    The present study was aimed at investigating the relationship between the mismatch negativity (MMN) and psychoacoustical effects of sequential streaming on comodulation masking release (CMR). The influence of sequential streaming on CMR was investigated using a psychoacoustical alternative forced-choice procedure and electroencephalography (EEG) for the same group of subjects. The psychoacoustical data showed, that adding precursors comprising of only off-signal-frequency maskers abolished the CMR. Complementary EEG data showed an MMN irrespective of the masker envelope correlation across frequency when only the off-signal-frequency masker components were present. The addition of such precursors promotes a separation of the on- and off-frequency masker components into distinct auditory objects preventing the auditory system from using comodulation as an additional cue. A frequency-specific adaptation changing the representation of the flanking bands in the streaming conditions may also contribute to the reduction of CMR in the stream conditions, however, it is unlikely that adaptation is the primary reason for the streaming effect. A neurophysiological correlate of sequential streaming was found in EEG data using MMN, but the magnitude of the MMN was not correlated with the audibility of the signal in CMR experiments. Dipole source analysis indicated different cortical regions involved in processing auditory streaming and modulation detection. In particular, neural sources for processing auditory streaming include cortical regions involved in decision-making. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Long latency auditory evoked potentials and central auditory processing in children with reading and writing alterations: Preliminary data

    Directory of Open Access Journals (Sweden)

    Soares, Aparecido José Couto

    2011-10-01

    Full Text Available Introduction: Presently, it is admitted that individuals with reading and writing alterations may present delay in the development of listening skills, which may interfere in the learning process. The assessment of the listening skills can occur in a behavioral way, through central auditory processing (CAP tests, or by electrophysiological assessment highlighting the long latency auditory evoked potentials (LLAEP. The use of the LLAEP as a means of complementary assessment of individuals with reading and writing alterations can become an important data both for further characterization of the alterations, as for the therapeutic guidance of this population. Objective: Characterize the CAP and the LLAEP in children with reading and writing alterations. Method: Research approved by the Institution's Ethic Commission under nº 305/10. The assessment of CAP and LLAEP was performed in 12 children aged between 8 and 12 years old (average of 10,6 years, with reading and writing alterations confirmed in specific evaluation. Results: The most altered CAP skills were temporal ordination and figure-ground for linguistic sounds. There were found altered results in P300 and in MMN. Conclusion: The individuals with reading and writing alterations performed below the expected on CAP tests. The MMN allowed a better characterization of the auditory function of this population. There was evidence of association between the CAP results and the alteration of the LLAEP.

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

    Science.gov (United States)

    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

  18. Brainstem Auditory Evoked Potentials' Diagnostic Accuracy for Hearing Loss: Systematic Review and Meta-Analysis

    National Research Council Canada - National Science Library

    Thirumala, Parthasarathy; Carnovale, Gregory; Loke, Yoon; Habeych, Miguel; Crammond, Donald; Balzer, Jeffrey; Sekula, Raymond

    2016-01-01

    ... The PubMed/MEDLINE and World Science databases were searched. Studies performed MVD for trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia or geniculate neuralgia and monitored intraoperative BAEPs to prevent hearing loss...

  19. Brainstem auditory evoked responses in healthy Argentine Mastiff dogs recorded with surface electrodes

    Directory of Open Access Journals (Sweden)

    M. Armașu

    2015-10-01

    Full Text Available RESUMOEvocado auditivo de respostas – BAER foi gravado utilizando eletrodos de superfície em sete cães Mastiff argentino saudáveis para estimulações monoaural e binaural em intensidades sonoras de 90 dB NPS . As latências e amplitudes das ondas I, III e V bem como os intervalos InterWave I- III , III -V e IV foram calculados. As diferenças estatísticas foram obtidas para as ondas III e latências V, amplitudes das ondas III e intervalos I- III e I-V entre mono e estimulação binaural. Por serem uma das raças geneticamente predispostas à surdez congênita, obtendo valores de referência BAER, os cães Mastiff argentino têm uma importância clínica especial.

  20. Hemispheric asymmetries for visual and auditory temporal processing: an evoked potential study.

    Science.gov (United States)

    Nicholls, Michael E R; Gora, John; Stough, Con K K

    2002-04-01

    Lateralization for temporal processing was investigated using evoked potentials to an auditory and visual gap detection task in 12 dextral adults. The auditory stimuli consisted of 300-ms bursts of white noise, half of which contained an interruption lasting 4 or 6 ms. The visual stimuli consisted of 130-ms flashes of light, half of which contained a gap lasting 6 or 8 ms. The stimuli were presented bilaterally to both ears or both visual fields. Participants made a forced two-choice discrimination using a bimanual response. Manipulations of the task had no effect on the early evoked components. However, an effect was observed for a late positive component, which occurred approximately 300-400 ms following gap presentation. This component tended to be later and lower in amplitude for the more difficult stimulus conditions. An index of the capacity to discriminate gap from no-gap stimuli was gained by calculating the difference waveform between these conditions. The peak of the difference waveform was delayed for the short-gap stimuli relative to the long-gap stimuli, reflecting decreased levels of difficulty associated with the latter stimuli. Topographic maps of the difference waveforms revealed a prominence over the left hemisphere. The visual stimuli had an occipital parietal focus whereas the auditory stimuli were parietally centered. These results confirm the importance of the left hemisphere for temporal processing and demonstrate that it is not the result of a hemispatial attentional bias or a peripheral sensory asymmetry.

  1. Modeling neural correlates of auditory attention in evoked potentials using corticothalamic feedback dynamics.

    Science.gov (United States)

    Trenado, Carlos; Haab, Lars; Strauss, Daniel J

    2007-01-01

    Auditory evoked cortical potentials (AECP) are well established as diagnostic tool in audiology and gain more and more impact in experimental neuropsychology, neuro-science, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation. The modulation of AECP due to exogenous and endogenous attention plays a major role in many clinical applications and has experimentally been studied in neuropsychology. However the relation of corticothalamic feedback dynamics to focal and non-focal attention and its large-scale effect reflected in AECPs is far from being understood. In this paper, we model neural correlates of auditory attention reflected in AECPs using corticothalamic feedback dynamics. We present a mapping of a recently developed multiscale model of evoked potentials to the hearing path and discuss for the first time its neurofunctionality in terms of corticothalamic feedback loops related to focal and non-focal attention. Our model reinforced recent experimental results related to online attention monitoring using AECPs with application as objective tinnitus decompensation measure. It is concluded that our model presents a promising approach to gain a deeper understanding of the neurodynamics of auditory attention and might be use as an efficient forward model to reinforce hypotheses that are obtained from experimental paradigms involving AECPs.

  2. Cochlear implantation versus auditory brainstem implantation in bilateral total deafness after head trauma: personal experience and review of the literature.

    Science.gov (United States)

    Medina, Marimar; Di Lella, Filippo; Di Trapani, Giuseppe; Prasad, Sampath Chandra; Bacciu, Andrea; Aristegui, Miguel; Russo, Alessandra; Sanna, Mario

    2014-02-01

    To determine the effectiveness of cochlear implant (CI) in hearing restoration after temporal bone (TB) fractures and investigate the adequacy of auditory brainstem implant (ABI) indication for TB fractures. Retrospective clinical study; a systematic review of the literature in PubMed was also performed to identify all published cases of bilateral TB fractures or bilateral deafness after head trauma treated by means of CI or ABI. Quaternary otology and skull base surgery referral center. Eleven consecutive patients presented with bilateral severe-to-profound sensorineural hearing loss after head trauma. CI as primary intervention or following a previous treatment. CI performances were evaluated in the auditory-only condition in both closed-set and open-set formats. Fourteen CI were placed, 11 as primary treatment and 3 after ABI failure. At the last follow-up, all patients gained useful open-set speech perception. In secondary CI, all patients obtained better auditory results with the CI if compared with ABI. CI performance did not decrease with time in any case. Cochlear implantation after TB fractures has proved to have excellent audiometric results. The aim of the initial evaluation of a patient with bilateral anacoustic ears from head trauma should always be to rehabilitate their hearing with a CI. The incidence of labyrinthitis ossificans, negative electrophysiologic testing, the risk of postoperative meningitis or facial nerve stimulation should not be the determinant factors that favor ABI placement.

  3. Auditory Perceptual and Visual-Spatial Characteristics of Gaze-Evoked Tinnitus

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    Jamileh Fattahi

    1996-09-01

    Full Text Available Auditory perceptual and visual-spatial characteristics of subjective tinnitus evoked by eye gaze were studied in two adult human subjects. This uncommon form of tinnitus occurred approximately 4-6 weeks following neurosurgery for gross total excision of space Occupying lesions of the cerebellopontine angle and hearing was lost in the operated ear. In both cases, the gaze evoked tinnitus was characterized as being tonal in nature, with pitch and loudness percepts remaining constant as long as the same horizontal or vertical eye directions were maintained. Tinnitus was absent when the eyes were in a neutral head referenced position with subjects looking straight ahead. The results and implications of ophthalmological, standard and modified visual field assessment, pure tone audio metric assessment, spontaneous otoacoustic emission testing and detailed psychophysical assessment of pitch and loudness are discussed

  4. Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma - a prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Lau, S.K.; Wei, W.I.; Sham, J.S.T.; Choy, D.T.K.; Hui, Y. (Queen Mary Hospital, Hong Kong (Hong Kong))

    1992-10-01

    A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway. (Author).

  5. 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

  6. Assessment of an ICA-based noise reduction method for multi-channel auditory evoked potentials

    Science.gov (United States)

    Mirahmadizoghi, Siavash; Bell, Steven; Simpson, David

    2015-03-01

    In this work a new independent component analysis (ICA) based method for noise reduction in evoked potentials is evaluated on for auditory late responses (ALR) captured with a 63-channel electroencephalogram (EEG) from 10 normal-hearing subjects. The performance of the new method is compared with a single channel alternative in terms of signal to noise ratio (SNR), the number of channels with an SNR above an empirically derived statistical critical value and an estimate of hearing threshold. The results show that the multichannel signal processing method can significantly enhance the quality of the signal and also detected hearing thresholds significantly lower than with the single channel alternative.

  7. Auditory evoked response: a new approach for the evaluation of the unborn fetus.

    Science.gov (United States)

    Pereira Luz, N; Pereira Lima, C; Germany Paula, L; Hecker Luz, J

    1980-01-01

    The authors present their preliminary results observed with sound stimulation of human fetuses, a new approach to the exploration of some brain functions during fetal life, using a behavioural procedure. By applying an adequate auditory stimulus to the abdomen of pregnant women in the last trimester of pregnancy and during labour, they were able to evoke a standard fetal heart rate and motor response. They describe the different patterns observed during labour as a preliminary report of what appears to be a new procedure for evaluation of fetal conditions in normal or abnormal environments.

  8. Interaction of Musicianship and Aging: A Comparison of Cortical Auditory Evoked Potentials

    Directory of Open Access Journals (Sweden)

    Jennifer L. O’Brien

    2015-01-01

    Full Text Available Objective. The goal of this study was to begin to explore whether the beneficial auditory neural effects of early music training persist throughout life and influence age-related changes in neurophysiological processing of sound. Design. Cortical auditory evoked potentials (CAEPs elicited by harmonic tone complexes were examined, including P1-N1-P2, mismatch negativity (MMN, and P3a. Study Sample. Data from older adult musicians (n=8 and nonmusicians (n=8 (ages 55–70 years were compared to previous data from young adult musicians (n=40 and nonmusicians (n=20 (ages 18–33 years. Results. P1-N1-P2 amplitudes and latencies did not differ between older adult musicians and nonmusicians; however, MMN and P3a latencies for harmonic tone deviances were earlier for older musicians than older nonmusicians. Comparisons of P1-N1-P2, MMN, and P3a components between older and young adult musicians and nonmusicians suggest that P1 and P2 latencies are significantly affected by age, but not musicianship, while MMN and P3a appear to be more sensitive to effects of musicianship than aging. Conclusions. Findings support beneficial influences of musicianship on central auditory function and suggest a positive interaction between aging and musicianship on the auditory neural system.

  9. Auditory brain-stem response, CT and MR imaging in a family with classical type Pelizaeus-Merzbacher Disease

    Energy Technology Data Exchange (ETDEWEB)

    Shiomi, M.; Ookuni, H.; Sugita, T.

    1987-05-01

    A family in which 5 males in successive generations were clinically suspected to be affected with the classical X-linked recessive form of Pelizaeus-Merzbacher disease (PMD) is presented. Two brothers and their maternal uncle were examined by one of the authors (MS). In two brothers, aged 3 years and 2 years, the disease became obvious within a month after birth with nystagmus and head tremor. Head control and sitting were achieved at the age of 18 months at which time they began to speak. They could not stand nor walk without support. They had dysmetria, weakness and hyper-reflexia of lower extremities, and mild mental retardation. Their maternal uncle, aged 37 years, showed psychomotor retardation from birth and subsequently developed spastic paraplegia. He had been able to walk with crutches until adolescence. He had dysmetria, scanning speech, athetoid posture of fingers and significant intellectual deficits. Auditory brainstem response in both brothers revealed well defined waves I and II, low amplitude wave III and an absence of all subsequent components. CT demonstrated mild cerebral atrophy in the elder brother and was normal in the younger brother, but in their uncle, CT showed atrophy of the brainstem, cerebellum and cerebrum, and low density of the white matter of the centrum semiovale. MRI was performed in both brothers. Although the brainstem, the internal capsule and the thalamus were myelinated, the myelination in the subcortical white matter was restricted to periventricular regions on IR sequence scans. On SE sequence, the subcortical white matter was imaged as a brighter area than the cerebral cortex. These results demonstrate that the degree of myelination in these patients was roughly equal to that of 3-to 6-month old infants.

  10. Objective detection of auditory steady-state evoked potentials based on mutual information.

    Science.gov (United States)

    Bidelman, Gavin M; Bhagat, Shaum P

    2016-01-01

    Recently, we developed a metric to objectively detect human auditory evoked potentials based on the mutual information (MI) between neural responses and stimulus spectrograms. Here, the MI algorithm is evaluated further for validity in testing the auditory steady-state response (ASSR), a sustained potential used in objective audiometry. MI was computed between spectrograms of ASSRs and their evoking stimuli to quantify the shared time-frequency information between neuroelectric activity and stimulus acoustics. MI was compared against two traditional ASSR detection metrics: F-test and magnitude-squared coherence (MSC). Using an empirically derived threshold (⊖MI=1.45), MI was applied as a binary classifier to distinguish actual biological responses recorded in human participants (n=11) from sham recordings, containing only EEG noise (i.e., non-stimulus-control condition). MI achieved high overall accuracy (>90%) in identifying true ASSRs from sham recordings, with true positive/true negative rates of 82/100%. During online averaging, comparison with two other indices (F-test, MSC) indicated that MI could detect ASSRs in roughly half the number of trials (i.e., ∼400 sweeps) as the MSC and performed comparably to the F-test, but showed slightly better signal detection performance. MI provides an alternative, more flexible metric for efficient and automated ASSR detection.

  11. Effects of stimulation intensity, gender and handedness upon auditory evoked potentials

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    Susana Camposano

    1992-03-01

    Full Text Available Left handers and women show less anatomical brain asymmetry, larger corpus callosum and more bilateral representation of specific functions. Sensory and cognitive components of cortical auditory evoked potentials (AEF have been shown to be asymmetric in right handed males and to be influenced by stimulus intensity. In this study the influence of sex, handedness and stimulus intensity upon AEP components is investigated under basal conditions of passive attention. 14 right handed males, 14 right handed females, 14 left handed males, and 14 left handed females were studied while lying awake and paying passive attention to auditory stimulation (series of 100 binaural clicks, duration 1 msec, rate 1/sec, at four intensities. Cz, C3 and C4 referenced to linked mastoids and right EOG were recorded. Analysis time was 400 msec, average evoked potentials were based on 100 clicks. Stimulus intensity and gender affect early sensory components (P1N1 and N1P2 at central leads, asymmetry is influenced only by handedness, right handers showing larger P1N1 amplitudes over the right hemisphere.

  12. Speech-evoked cortical auditory responses in children with normal hearing

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    Aseel Almeqbel

    2013-12-01

    Full Text Available Objective: Cortical auditory-evoked potentials (CAEPs, an objective measure of human speech encoding in individuals with normal or impaired auditory systems, can be used to assess the outcomes of hearing aids and cochlear implants in infants, or in young children who cannot co-operate for behavioural speech discrimination testing. The current study aimed to determine whether naturally produced speech stimuli /m/, /g/ and /t/ evoke distinct CAEP response patterns that can be reliably recorded and differentiated, based on their spectral information and whether the CAEP could be an electrophysiological measure to differentiate between these speech sounds.Method: CAEPs were recorded from 18 school-aged children with normal hearing, tested in two groups: younger (5 - 7 years and older children (8 - 12 years. Cortical responses differed in their P1 and N2 latencies and amplitudes in response to /m/, /g/ and /t/ sounds (from low-, mid- and high-frequency regions, respectively. The largest amplitude of the P1 and N2 component was for /g/ and the smallest was for /t/. The P1 latency in both age groups did not show any significant difference between these speech sounds. The N2 latency showed a significant change in the younger group but not in the older group. The N2 latency of the speech sound /g/ was always noted earlier in both groups.Conclusion: This study demonstrates that spectrally different speech sounds are encoded differentially at the cortical level, and evoke distinct CAEP response patterns. CAEP latencies and amplitudes may provide an objective indication that spectrally different speech sounds are encoded differently at the cortical level.

  13. the variability in P300 cognitive evoked potential amplitude in the auditory oddball paradigm

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    Biševac B.

    2015-01-01

    Full Text Available One of the best-studied responses of cognitive evoked potentials is a so-called 'P300', the late positive wave complex that occurs about 300-500 ms after the stimulus. It is obtained when the subject's attention is focused on a signal that is rare, especially if the signal has a motivational or emotional meaning. In the study of P300 potential, we followed the variations of potential amplitude and latency, so the objective was to examine whether there is a difference in Fz and Cz amplitudes of auditory induced cognitive evoked P300 potential depending on the performance of oddball tasks, both in male and female subjects. The study included 60 subjects (30 female respondents and 30 male respondents. P300 potential is induced by the auditory 'oddball' paradigm with 80% of non-target and 20% of target stimuli that are presented to the patient through headphones. The target tones are high tones of 2000 Hz. The standard, 1000 Hz tones the respondent should ignore but when he hears the target tones the respondent should press the button on the special handle. The value of Fz and Cz amplitudes both in male and female subjects obtained in the classical 'oddball' paradigm when the subject reacted to the signal by pressing the key with the dominant (right arm were statistically significantly lower (p>0,05 than the values of Fz and Cz amplitudes obtained when the key was pressed by the non-dominant hand. Based on this experiment it can be concluded that both in male and female subjects the performance of oddball tasks does not affect the amplitude of P300 cognitive evoked potentials.

  14. Objective measures of binaural masking level differences and comodulation masking release based on late auditory evoked potentials

    DEFF Research Database (Denmark)

    Epp, Bastian; Yasin, Ifat; Verhey, Jesko L.

    2013-01-01

    The audibility of important sounds is often hampered due to the presence of other masking sounds. The present study investigates if a correlate of the audibility of a tone masked by noise is found in late auditory evoked potentials measured from human listeners. The audibility of the target sound...... in a masking release (i: binaural masking level difference; ii: comodulation masking release) compared to a condition where those cues are not present. Late auditory evoked potentials (N1, P2) were recorded for the stimuli at a constant masker level, but different signal levels within the same set of listeners...

  15. Transient evoked otoacoustic emissions and contralateral suppressions in children with auditory listening problems.

    Science.gov (United States)

    Yalçinkaya, Fulya; Yilmaz, Suna Tokgöz; Muluk, Nuray Bayar

    2010-02-01

    Transient evoked otoacoustic emissions (TEOAEs) are reflections of cochlear energy produced during the processing of sound. The suppression effect identified as the decrease with the additional tone stimulator of the otoacoustic emission amplitude is use for assessing efferent auditory system function. The aim of this study is to investigate the contralateral suppression effect (CSE) of transient evoked otoacoustic emissions (TEOAEs) in children with auditory listening problems (ALPs) compared to normal hearing children. The study group (Group 1) was consisted of 12 ALP children (8 males and 4 females), aged 5-10 years, and associated with receptive and expressive language delay. The control group was consisted of (Group 2) 12 children with normal hearing levels, matched according to gender and age of TEOAEs and CSE of TEOAEs were investigated at 1.0-4.0 kHz in both groups. For right ear, at 1.0 and 3.0 kHz, TEOAE amplitudes of the ALP group were significantly lower than the control group. At 2.0, 4.0 and 5.0 kHz of the right ear and at 1.0-5.0 kHz of the left ear, TEOAE amplitudes were found as not different between ALP and control groups. Suppression values of the ALP group were significantly lower than the control group at 1.0-2.0 kHz of the right ear and at 2.0 kHz of the left ear. At the other frequencies, there was no significant difference between the suppression values of the ALP and control groups. Lower suppression values in ALP group at all frequencies (significant at 1.0-2.0 and 2.0 kHz in the right and left ears, respectively) showed that cochlear and cranial maturation of the ALP group may lower than the control group. Since the age profile in both group is similar, we thought that age's effect on this results is not important. Our results showed that children with ALP have auditory processing difficulties in noisy environment. For understanding the efferent auditory system, patients with auditory processing disorders may be evaluated by the help of

  16. Analog very large-scale integrated (VLSI) implementation of a model of amplitude-modulation sensitivity in the auditory brainstem.

    Science.gov (United States)

    van Schaik, A; Meddis, R

    1999-02-01

    An analog very large-scale integrated (VLSI) implementation of a model of signal processing in the auditory brainstem is presented and evaluated. The implementation is based on a model of amplitude-modulation sensitivity in the central nucleus of the inferior colliculus (CNIC) previously described by Hewitt and Meddis [J. Acoust. Soc. Am. 95, 2145-2159 (1994)]. A single chip is used to implement the three processing stages of the model; the inner-hair cell (IHC), cochlear nucleus sustained-chopper, and CNIC coincidence-detection stages. The chip incorporates two new circuits: an IHC circuit and a neuron circuit. The input to the chip is taken from a "silicon cochlea" consisting of a cascade of filters that simulate basilar membrane mechanical frequency selectivity. The chip which contains 142 neurons was evaluated using amplitude-modulated pure tones. Individual cells in the CNIC stage demonstrate bandpass rate-modulation responses using these stimuli. The frequency of modulation is represented spatially in an array of these cells as the location of the cell generating the highest rate of action potentials. The chip processes acoustic signals in real time and demonstrates the feasibility of using analog VLSI to build and test auditory models that use large numbers of component neurons.

  17. Neonate Auditory Brainstem Responses to CE-Chirp and CE-Chirp Octave Band Stimuli I: Versus Click and Tone Burst Stimuli.

    Science.gov (United States)

    Cobb, Kensi M; Stuart, Andrew

    The purpose of the study was to generate normative auditory brainstem response (ABR) wave component peak latency and amplitude values for neonates with air- and bone-conducted CE-Chirps and air-conducted CE-Chirp octave band stimuli (i.e., 500, 1000, 2000, and 4000 Hz). A second objective was to compare neonate ABRs to CE-Chirp stimuli with ABR responses to traditional click and tone burst stimuli with the same stimulus parameters. Participants were 168 healthy neonates. ABRs were obtained to air- and bone-conducted CE-Chirp and click stimuli and air-conducted CE-Chirp octave band and tone burst stimuli. The effects of stimulus level, rate, and polarity were examined with air-conducted CE-Chirps and clicks. The effect of stimulus level was also examined with bone-conducted CE-Chirps and clicks and air-conducted CE-Chirp octave band stimuli. In general, ABR wave V amplitudes to air- and bone-conducted CE-Chirp stimuli were significantly larger (p < 0.05) than those evoked to traditional click and tone burst stimuli. Systematic statistically significant (p < 0.05) wave V latency differences existed between the air- and bone-conducted CE-Chirp and CE-Chirp octave band stimuli relative to traditional click and tone burst stimuli. ABRs to air- and bone-conducted CE-Chirps and CE-Chirp octave band stimuli may be valuable in the assessment of newborn infants. However, the prognostic value of such stimuli needs to be validated.

  18. Gating of the vertex somatosensory and auditory evoked potential P50 and the correlation to skin conductance orienting response in healthy men

    DEFF Research Database (Denmark)

    Arnfred, S M; Eder, D N; Hemmingsen, R P

    2001-01-01

    A defect in auditory evoked potential (AEP) P50 gating supports the theory of information-processing deficits in schizophrenia. The relationship between gating of the mid-latency evoked potentials (EP) in the somatosensory and the auditory modalities has not been studied together before. In schiz...

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

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

    2009-01-01

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

  20. Effects of aging on inner ear morphology in dogs in relation to brainstem responses to toneburst auditory stimuli.

    Science.gov (United States)

    Ter Haar, G; de Groot, J C M J; Venker-van Haagen, A J; van Sluijs, F J; Smoorenburg, G F

    2009-01-01

    Age-related hearing loss (ARHL) is the most common form of hearing loss in humans and is increasingly recognized in dogs. Cochlear lesions in dogs with ARHL are similar to those in humans and the severity of the histological changes is reflected in tone audiograms. Ten geriatric dogs (mean age: 12.7 years) and three 9-month-old dogs serving as controls for histological analysis. Observational study. Auditory thresholds were determined by recording brainstem responses (BERA) to toneburst auditory stimuli (1, 2, 4, 8, 12, 16, 24, and 32 kHz). After euthanasia and perfusion fixation, the temporal bones were harvested and processed for histological examination of the cochleas. The numbers of outer hair cells (OHCs) and inner hair cells (IHCs) were counted and the spiral ganglion cell (SGC) packing density and stria vascularis cross-sectional area (SVCA) were determined. A combination of cochlear lesions was found in all geriatric dogs. There were significant reductions (P .001) in OHC (42%, 95% confidence interval [CI]; 24-64%) and IHC counts (21%, 95% CI; 62-90%) and SGC packing densities (323, 95% CI; 216-290) in the basal turn, SVCA was smaller in all turns. The greatest reduction in auditory sensitivity was at 8-32 kHz. ARHL in this specific population of geriatric dogs was comparable histologically to the mixed type of ARHL in humans. The predominance of histological changes in the basal cochlear turn was consistent with the large threshold shifts observed in the middle- to high-frequency region.

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

    Science.gov (United States)

    Gourévitch, Boris; Edeline, Jean-Marc

    2011-12-01

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

  2. Modulation of auditory evoked responses to spectral and temporal changes by behavioral discrimination training

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    Okamoto Hidehiko

    2009-12-01

    Full Text Available Abstract Background Due to auditory experience, musicians have better auditory expertise than non-musicians. An increased neocortical activity during auditory oddball stimulation was observed in different studies for musicians and for non-musicians after discrimination training. This suggests a modification of synaptic strength among simultaneously active neurons due to the training. We used amplitude-modulated tones (AM presented in an oddball sequence and manipulated their carrier or modulation frequencies. We investigated non-musicians in order to see if behavioral discrimination training could modify the neocortical activity generated by change detection of AM tone attributes (carrier or modulation frequency. Cortical evoked responses like N1 and mismatch negativity (MMN triggered by sound changes were recorded by a whole head magnetoencephalographic system (MEG. We investigated (i how the auditory cortex reacts to pitch difference (in carrier frequency and changes in temporal features (modulation frequency of AM tones and (ii how discrimination training modulates the neuronal activity reflecting the transient auditory responses generated in the auditory cortex. Results The results showed that, additionally to an improvement of the behavioral discrimination performance, discrimination training of carrier frequency changes significantly modulates the MMN and N1 response amplitudes after the training. This process was accompanied by an attention switch to the deviant stimulus after the training procedure identified by the occurrence of a P3a component. In contrast, the training in discrimination of modulation frequency was not sufficient to improve the behavioral discrimination performance and to alternate the cortical response (MMN to the modulation frequency change. The N1 amplitude, however, showed significant increase after and one week after the training. Similar to the training in carrier frequency discrimination, a long lasting

  3. Auditory evoked responses in musicians during passive vowel listening are modulated by functional connectivity between bilateral auditory-related brain regions.

    Science.gov (United States)

    Kühnis, Jürg; Elmer, Stefan; Jäncke, Lutz

    2014-12-01

    Currently, there is striking evidence showing that professional musical training can substantially alter the response properties of auditory-related cortical fields. Such plastic changes have previously been shown not only to abet the processing of musical sounds, but likewise spectral and temporal aspects of speech. Therefore, here we used the EEG technique and measured a sample of musicians and nonmusicians while the participants were passively exposed to artificial vowels in the context of an oddball paradigm. Thereby, we evaluated whether increased intracerebral functional connectivity between bilateral auditory-related brain regions may promote sensory specialization in musicians, as reflected by altered cortical N1 and P2 responses. This assumption builds on the reasoning that sensory specialization is dependent, at least in part, on the amount of synchronization between the two auditory-related cortices. Results clearly revealed that auditory-evoked N1 responses were shaped by musical expertise. In addition, in line with our reasoning musicians showed an overall increased intracerebral functional connectivity (as indexed by lagged phase synchronization) in theta, alpha, and beta bands. Finally, within-group correlative analyses indicated a relationship between intracerebral beta band connectivity and cortical N1 responses, however only within the musicians' group. Taken together, we provide first electrophysiological evidence for a relationship between musical expertise, auditory-evoked brain responses, and intracerebral functional connectivity among auditory-related brain regions.

  4. Effect of Pulse Rate and Polarity on the Sensitivity of Auditory Brainstem and Cochlear Implant Users to Electrical Stimulation.

    Science.gov (United States)

    Carlyon, Robert P; Deeks, John M; McKay, Colette M

    2015-10-01

    To further understand the response of the human brainstem to electrical stimulation, a series of experiments compared the effect of pulse rate and polarity on detection thresholds between auditory brainstem implant (ABI) and cochlear implant (CI) patients. Experiment 1 showed that for 400-ms pulse trains, ABI users' thresholds dropped by about 2 dB as pulse rate was increased from 71 to 500 pps, but only by an average of 0.6 dB as rate was increased further to 3500 pps. This latter decrease was much smaller than the 7.7-dB observed for CI users. A similar result was obtained for pulse trains with a 40-ms duration. Furthermore, experiment 2 showed that the threshold difference between 500- and 3500-pps pulse trains remained much smaller for ABI than for CI users, even for durations as short as 2 ms, indicating the effect of a fast-acting mechanism. Experiment 3 showed that ABI users' thresholds were lower for alternating-polarity than for fixed-polarity pulse trains, and that this difference was greater at 3500 pps than at 500 pps, consistent with the effect of pulse rate on ABI users' thresholds being influenced by charge interactions between successive biphasic pulses. Experiment 4 compared thresholds and loudness between trains of asymmetric pulses of opposite polarity, in monopolar mode, and showed that in both cases less current was needed when the anodic, rather than the cathodic, current was concentrated into a short time interval. This finding is similar to that previously observed for CI users and is consistent with ABI users being more sensitive to anodic than cathodic current. We argue that our results constrain potential explanations for the differences in the perception of electrical stimulation by CI and ABI users, and have potential implications for future ABI stimulation strategies.

  5. Clinical Application of the P1 Cortical Auditory Evoked Potential Biomarker in Children with Sensorineural Hearing Loss and Auditory Neuropathy Spectrum Disorder.

    Science.gov (United States)

    Campbell, Julia Dee; Cardon, Garrett; Sharma, Anu

    2011-05-01

    The P1 component of the cortical auditory evoked potential (CAEP) shows clearly documented age-related decreases in latency and changes in morphology in normal hearing children, providing a biomarker for development of the auditory cortical pathways in humans. In hearing-impaired children, auditory deprivation may affect the normal age-related changes in central auditory maturation. Appropriate early intervention with amplification and/or electrical stimulation can provide the necessary stimulation needed to drive progress in central auditory maturation and auditory skill development, however objective measures are needed to evaluate the effectiveness of these treatments in infants and young children. We describe three pediatric cases, where we explored the clinical utility of the P1 as an objective biomarker of auditory cortical development after early intervention. We assessed development of P1 CAEP latency and morphology in two children with sensorineural hearing loss (SNHL) who received intervention with hearing aids (case 1) and cochlear implants (case 2) and a child with Auditory Neuropathy Spectrum Disorder (ANSD) (case 3). Overall, we find that the P1 CAEP serves as useful tool for assessing the effectiveness of early intervention treatment and clinical management of pediatric hearing- impaired patients.

  6. AN EFFICIENT PEAK VALLEY DETECTION BASED VAD ALGORITHM FOR ROBUST DETECTION OF SPEECH AUDITORY BRAINSTEM RESPONSES

    OpenAIRE

    Ranganadh Narayanam

    2013-01-01

    Voice Activity Detection (VAD) problem considers detecting the presence of speech in a noisy signal. The speech/non-speech classification task is not as trivial as it appears, and most of the VAD algorithms fail when the level of background noise increases. In this research we are presenting a new technique for Voice Activity Detection (VAD) in EEG collected brain stem speech evoked potentials data [7, 8, 9]. This one is spectral subtraction method in which we have developed ou...

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

    DEFF Research Database (Denmark)

    Junius, D.; Dau, Torsten

    2005-01-01

    ), disparities occurred between the responses, reflecting a nonlinearity in the processing when neural activity is integrated across frequency. In the third experiment, the effect of within-train rate on wave-V response was investigated. The response to the chirp presented at a within-train rate of 95 Hz...... processing in the human auditory system. The findings might also be useful for the development of effective stimulation paradigms in clinical applications....

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Long-latency auditory evoked potentials with verbal and nonverbal stimuli,

    Directory of Open Access Journals (Sweden)

    Sheila Jacques Oppitz

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. OBJECTIVE: To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. METHODS: A total of 30 subjects with normal hearing were assessed, aged 18-32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000 Hz - frequent and 4000 Hz - rare; and verbal (/ba/ - frequent; /ga/, /da/, and /di/ - rare. RESULTS: Considering the component N2 for tone burst, the lowest latency found was 217.45 ms for the BA/DI stimulus; the highest latency found was 256.5 ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340 ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. CONCLUSION: There was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude.

  11. Amphibious auditory evoked potentials in four North American Testudines genera spanning the aquatic-terrestrial spectrum.

    Science.gov (United States)

    Zeyl, Jeffrey N; Johnston, Carol E

    2015-10-01

    Animals exhibit unique hearing adaptations in relation to the habitat media in which they reside. This study was a comparative analysis of auditory specialization in relation to habitat medium in Testudines, a taxon that includes both highly aquatic and fully terrestrial members. Evoked potential audiograms were collected in four species groups representing diversity along the aquatic-terrestrial spectrum: terrestrial and fossorial Gopherus polyphemus, terrestrial Terrapene carolina carolina, and aquatic Trachemys scripta and Sternotherus (S. odoratus and S. minor). Additionally, underwater sensitivity was tested in T. c. carolina, T. scripta, and Sternotherus with tympana submerged just below the water surface. In aerial audiograms, T. c. carolina were most sensitive, with thresholds 18 dB lower than Sternotherus. At 100-300 Hz, thresholds in T. c. carolina, G. polyphemus, and T. scripta were similar to each other. At 400-800 Hz, G. polyphemus thresholds were elevated to 11 dB above T. c. carolina. The underwater audiograms of T. c. carolina, T. scripta, and Sternotherus were similar. The results suggest aerial hearing adaptations in emydids and high-frequency hearing loss associated with seismic vibration detection in G. polyphemus. The underwater audiogram of T. c. carolina could reflect retention of ancestral aquatic auditory function.

  12. Sensitivity of offset and onset cortical auditory evoked potentials to signals in noise.

    Science.gov (United States)

    Baltzell, Lucas S; Billings, Curtis J

    2014-02-01

    The purpose of this study was to determine the effects of SNR and signal level on the offset response of the cortical auditory evoked potential (CAEP). Successful listening often depends on how well the auditory system can extract target signals from competing background noise. Both signal onsets and offsets are encoded neurally and contribute to successful listening in noise. Neural onset responses to signals in noise demonstrate a strong sensitivity to signal-to-noise ratio (SNR) rather than signal level; however, the sensitivity of neural offset responses to these cues is not known. We analyzed the offset response from two previously published datasets for which only the onset response was reported. For both datasets, CAEPs were recorded from young normal-hearing adults in response to a 1000-Hz tone. For the first dataset, tones were presented at seven different signal levels without background noise, while the second dataset varied both signal level and SNR. Offset responses demonstrated sensitivity to absolute signal level in quiet, SNR, and to absolute signal level in noise. Offset sensitivity to signal level when presented in noise contrasts with previously published onset results. This sensitivity suggests a potential clinical measure of cortical encoding of signal level in noise.

  13. Neural generators of the auditory evoked potential components P3a and P3b.

    Science.gov (United States)

    Wronka, Eligiusz; Kaiser, Jan; Coenen, Anton M L

    2012-01-01

    The aim of the present study was to define the scalp topography of the two subcomponents of the P3 component of the auditory evoked potential elicited in a three-stimulus oddball paradigm and to identify their cortical generators using the standardized low resolution electromagnetic tomography (sLORETA). Subjects were presented with a random sequence of auditory stimuli and instructed to respond to an infrequently occurring target stimulus inserted into a sequence of frequent standard and rare non-target stimuli. Results show that the magnitude of the frontal P3a is determined by the relative physical difference among stimuli, as it was larger for the stimulus more deviant from the standard. Major neural generators of the P3a were localized within frontal cortex and anterior cingulate gyrus. In contrast to this, the P3b, showing maximal amplitude at parietal locations, was larger for stimuli demanding a response than for the rare non-target. Major sources of the P3b included the superior parietal lobule and the posterior part of the cingulate gyrus. Our findings are in line with the hypothesis that P3a is related to alerting activity during the initial allocation of attention, while P3b is related to activation of a posterior network when the neuronal model of perceived stimulation is compared with the attentional trace.

  14. Otoacoustic emissions, auditory evoked potentials, and traits related to sex and sexual orientation.

    Science.gov (United States)

    Loehlin, John C; McFadden, Dennis

    2003-04-01

    A number of trait measures, possibly reflective of prenatal hormonal effects, were obtained in studies of otoacoustic emissions (OAEs) and auditory evoked potentials (AEPs) carried out with male and female heterosexual and homosexual/bisexual college students. Most of the measures were from a self-report questionnaire; others were from experimenters' ratings or cognitive tests (Mental Rotation Test and Water Level Test). The questionnaire, test, and rating measures included physical characteristics (e.g., height, body type, eye color); spatial abilities; sex roles and sexual orientation; childhood gender nonconformity; and, in the OAE study, presence of homosexuality or bisexuality among relatives. Correlations with sexual orientation were most often consistent with the hypothesis that male homosexuals were undermasculinized and female homosexuals overmasculinized. Some correlations of the questionnaire, test, and rating measures with auditory measures were observed, but most of these were reduced or eliminated by statistically controlling for sex. In supplementary analyses, pigmentation measures appeared to be unrelated to OAEs, and data relevant to several hypotheses in the sexual orientation literature were briefly examined, including childhood gender nonconformity, X-linkage, handedness, and the tendency of homosexuality to run in families.

  15. Long-Lasting Sound-Evoked Afterdischarge in the Auditory Midbrain.

    Science.gov (United States)

    Ono, Munenori; Bishop, Deborah C; Oliver, Douglas L

    2016-02-12

    Different forms of plasticity are known to play a critical role in the processing of information about sound. Here, we report a novel neural plastic response in the inferior colliculus, an auditory center in the midbrain of the auditory pathway. A vigorous, long-lasting sound-evoked afterdischarge (LSA) is seen in a subpopulation of both glutamatergic and GABAergic neurons in the central nucleus of the inferior colliculus of normal hearing mice. These neurons were identified with single unit recordings and optogenetics in vivo. The LSA can continue for up to several minutes after the offset of the sound. LSA is induced by long-lasting, or repetitive short-duration, innocuous sounds. Neurons with LSA showed less adaptation than the neurons without LSA. The mechanisms that cause this neural behavior are unknown but may be a function of intrinsic mechanisms or the microcircuitry of the inferior colliculus. Since LSA produces long-lasting firing in the absence of sound, it may be relevant to temporary or chronic tinnitus or to some other aftereffect of long-duration sound.

  16. Effects of Visual Speech on Early Auditory Evoked Fields - From the Viewpoint of Individual Variance.

    Directory of Open Access Journals (Sweden)

    Izumi Yahata

    Full Text Available The effects of visual speech (the moving image of the speaker's face uttering speech sound on early auditory evoked fields (AEFs were examined using a helmet-shaped magnetoencephalography system in 12 healthy volunteers (9 males, mean age 35.5 years. AEFs (N100m in response to the monosyllabic sound /be/ were recorded and analyzed under three different visual stimulus conditions, the moving image of the same speaker's face uttering /be/ (congruent visual stimuli or uttering /ge/ (incongruent visual stimuli, and visual noise (still image processed from speaker's face using a strong Gaussian filter: control condition. On average, latency of N100m was significantly shortened in the bilateral hemispheres for both congruent and incongruent auditory/visual (A/V stimuli, compared to the control A/V condition. However, the degree of N100m shortening was not significantly different between the congruent and incongruent A/V conditions, despite the significant differences in psychophysical responses between these two A/V conditions. Moreover, analysis of the magnitudes of these visual effects on AEFs in individuals showed that the lip-reading effects on AEFs tended to be well correlated between the two different audio-visual conditions (congruent vs. incongruent visual stimuli in the bilateral hemispheres but were not significantly correlated between right and left hemisphere. On the other hand, no significant correlation was observed between the magnitudes of visual speech effects and psychophysical responses. These results may indicate that the auditory-visual interaction observed on the N100m is a fundamental process which does not depend on the congruency of the visual information.

  17. Increased Evoked Potentials to Arousing Auditory Stimuli during Sleep: Implication for the Understanding of Dream Recall.

    Science.gov (United States)

    Vallat, Raphael; Lajnef, Tarek; Eichenlaub, Jean-Baptiste; Berthomier, Christian; Jerbi, Karim; Morlet, Dominique; Ruby, Perrine M

    2017-01-01

    High dream recallers (HR) show a larger brain reactivity to auditory stimuli during wakefulness and sleep as compared to low dream recallers (LR) and also more intra-sleep wakefulness (ISW), but no other modification of the sleep macrostructure. To further understand the possible causal link between brain responses, ISW and dream recall, we investigated the sleep microstructure of HR and LR, and tested whether the amplitude of auditory evoked potentials (AEPs) was predictive of arousing reactions during sleep. Participants (18 HR, 18 LR) were presented with sounds during a whole night of sleep in the lab and polysomnographic data were recorded. Sleep microstructure (arousals, rapid eye movements (REMs), muscle twitches (MTs), spindles, KCs) was assessed using visual, semi-automatic and automatic validated methods. AEPs to arousing (awakenings or arousals) and non-arousing stimuli were subsequently computed. No between-group difference in the microstructure of sleep was found. In N2 sleep, auditory arousing stimuli elicited a larger parieto-occipital positivity and an increased late frontal negativity as compared to non-arousing stimuli. As compared to LR, HR showed more arousing stimuli and more long awakenings, regardless of the sleep stage but did not show more numerous or longer arousals. These results suggest that the amplitude of the brain response to stimuli during sleep determine subsequent awakening and that awakening duration (and not arousal) is the critical parameter for dream recall. Notably, our results led us to propose that the minimum necessary duration of an awakening during sleep for a successful encoding of dreams into long-term memory is approximately 2 min.

  18. [Verbal auditory agnosia: SPECT study of the brain].

    Science.gov (United States)

    Carmona, C; Casado, I; Fernández-Rojas, J; Garín, J; Rayo, J I

    1995-01-01

    Verbal auditory agnosia are rare in clinical practice. Clinically, it characterized by impairment of comprehension and repetition of speech but reading, writing, and spontaneous speech are preserved. So it is distinguished from generalized auditory agnosia by the preserved ability to recognize non verbal sounds. We present the clinical picture of a forty-years-old, right handed woman who developed verbal auditory agnosic after an bilateral temporal ischemic infarcts due to atrial fibrillation by dilated cardiomyopathie. Neurophysiological studies by pure tone threshold audiometry: brainstem auditory evoked potentials and cortical auditory evoked potentials showed sparing of peripheral hearing and intact auditory pathway in brainstem but impaired cortical responses. Cranial CT-SCAN revealed two large hypodenses area involving both cortico-subcortical temporal lobes. Cerebral SPECT using 99mTc-HMPAO as radiotracer showed hypoperfusion just posterior in both frontal lobes nect to Roland's fissure and at level of bitemporal lobes just anterior to Sylvian's fissure.

  19. Task-specific modulation of human auditory evoked responses in a delayed-match-to-sample task

    Directory of Open Access Journals (Sweden)

    Feng eRong

    2011-05-01

    Full Text Available In this study, we focus our investigation on task-specific cognitive modulation of early cortical auditory processing in human cerebral cortex. During the experiments, we acquired whole-head magnetoencephalography (MEG data while participants were performing an auditory delayed-match-to-sample (DMS task and associated control tasks. Using a spatial filtering beamformer technique to simultaneously estimate multiple source activities inside the human brain, we observed a significant DMS-specific suppression of the auditory evoked response to the second stimulus in a sound pair, with the center of the effect being located in the vicinity of the left auditory cortex. For the right auditory cortex, a non-invariant suppression effect was observed in both DMS and control tasks. Furthermore, analysis of coherence revealed a beta band (12 ~ 20 Hz DMS-specific enhanced functional interaction between the sources in left auditory cortex and those in left inferior frontal gyrus, which has been shown to involve in short-term memory processing during the delay period of DMS task. Our findings support the view that early evoked cortical responses to incoming acoustic stimuli can be modulated by task-specific cognitive functions by means of frontal-temporal functional interactions.

  20. 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 exposure group exposure group and late gestational exposure group. Noise exposure during pregnancy influenced ABR thresholds in neonatal 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.

  1. Relationship between pure tone audiometry and tone burst auditory brainstem response at low frequencies gated with Blackman window.

    Science.gov (United States)

    Canale, Andrea; Dagna, Federico; Lacilla, Michelangelo; Piumetto, Elena; Albera, Roberto

    2012-03-01

    To assess the reliability of Blackman windowed tone burst auditory brainstem response (ABR) as a predictor of hearing threshold at low frequencies. Fifty-six subjects were divided in to three groups (normal hearing, conductive hearing loss, sensorineural hearing loss) after pure tone audiometry (PTA) testing. Then they underwent tone burst ABR using Blackman windowed stimuli at 0.5 kHz and 1 kHz. Results were compared with PTA threshold. Mean threshold differences between PTA and ABR ranged between 11 dB at 0.5 kHz and 14 dB at 1 kHz. ABR threshold was worse than PTA in each but 2 cases. Mean discrepancy between the two thresholds was about 20 dB in normal hearing, reducing in presence of hearing loss, without any differences in conductive and sensorineural cases. Tone burst ABR is a good predictor of hearing threshold at low frequencies, in case of suspected hearing loss. Further studies are recommended to evaluate an ipsilateral masking such as notched noise to ensure greater frequency specificity.

  2. Accuracy of auditory steady state and auditory brainstem responses to detect the preventive effect of polyphenols on age-related hearing loss in Sprague-Dawley rats.

    Science.gov (United States)

    Sanz-Fernández, Ricardo; Sánchez-Rodriguez, Carolina; Granizo, José Juan; Durio-Calero, Enrique; Martín-Sanz, Eduardo

    2016-02-01

    Aging causes histological, electrophysiological and molecular changes in the cochlea. The free radical theory of aging, has obtained consensus, and the mitochondrion is reported to play a key role in aging as a major source of reactive oxygen species. In the last years, there has been a significant increase in the interest in polyphenols because of the antioxidant properties and their role in the prevention of various diseases associated with oxidative stress, including aging. The aim of this study was to evaluate the preventive effect of different polyphenols on ARHL with auditory-evoked potentials. 100 Healthy female Sprague-Dawley (SD) rats were used for this study. Five groups were created based on the age of the rats, in months: 3, 6, 12, 18 and 24 months old. Two additional groups were created based on the treatment received. In the control group, 50 animals were assigned to no treatment. In the treated group, 50 animals were given a vehicle mixture of polyphenols for the half of the life before euthanization. Nine frequencies were tested (0.5-16 kHz) with ASSR and tone-burst ABR, performed on all of the rats prior to sacrifice. 100-μs auditory clicks ABRs were also recorded. A significant decrease in the audition was detected with ABR and ASSR in both treated and non-treated groups, as the different groups became older. This deterioration was more accurately measured at acute frequencies. Significantly lower thresholds were observed in the treated rats in the 6, 12 and 18-month-old group in the treated rats compared with the control group. All of the thresholds elicited using the ASSR technique were lower than the thresholds obtained using the ABR, regardless of the stimulus type. The present study demonstrated the benefits of the polyphenols, which generated a significant protection against ARHL, with significantly improved ASSR and tone-burst ABR auditory thresholds in rats receiving treatment with polyphenols.

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Analysis of electrically evoked compound action potential of the auditory nerve in children with bilateral cochlear implants.

    Science.gov (United States)

    Caldas, Fernanda Ferreira; Cardoso, Carolina Costa; Barreto, Monique Antunes de Souza Chelminski; Teixeira, Marina Santos; Hilgenberg, Anacléia Melo da Silva; Serra, Lucieny Silva Martins; Bahmad Junior, Fayez

    2016-01-01

    The cochlear implant device has the capacity to measure the electrically evoked compound action potential of the auditory nerve. The neural response telemetry is used in order to measure the electrically evoked compound action potential of the auditory nerve. To analyze the electrically evoked compound action potential, through the neural response telemetry, in children with bilateral cochlear implants. This is an analytical, prospective, longitudinal, historical cohort study. Six children, aged 1-4 years, with bilateral cochlear implant were assessed at five different intervals during their first year of cochlear implant use. There were significant differences in follow-up time (p=0.0082) and electrode position (p=0.0019) in the T-NRT measure. There was a significant difference in the interaction between time of follow-up and electrode position (p=0.0143) when measuring the N1-P1 wave amplitude between the three electrodes at each time of follow-up. The electrically evoked compound action potential measurement using neural response telemetry in children with bilateral cochlear implants during the first year of follow-up was effective in demonstrating the synchronized bilateral development of the peripheral auditory pathways in the studied population. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  5. Deconvolution of overlapping cortical auditory evoked potentials recorded using short stimulus onset-asynchrony ranges.

    Science.gov (United States)

    Bardy, Fabrice; Van Dun, Bram; Dillon, Harvey; McMahon, Catherine M

    2014-04-01

    The first aim of this study is to validate the theoretical framework of least-squares (LS) deconvolution on experimental data. The second is to investigate the waveform morphology of the cortical auditory evoked potential (CAEP) for five stimulus onset-asynchronies (SOAs) and effects of alternating stimulus frequency in normally hearing adults. Eleven adults (19-55 years) with normal hearing were investigated using tone-burst stimuli of 500 and 2000 Hz with SOAs jittered around 150, 250, 450, and 850 ms in a paired-interval paradigm with fixed or alternating stimulus frequency. The LS deconvolution technique disentangled the overlapping responses, which then provided the following insights. The CAEP amplitude reached a minimum value for SOAs jittered around 450 ms, in contrast with significantly larger amplitudes for SOAs jittered around 150 and 850 ms. Despite this, longer latencies of N1 and P2 consistently occurred for decreasing SOAs. Alternating stimulus frequency significantly increased the amplitude of the CAEP response and decreased latencies for SOAs jittered around 150 ms. Effects of SOAs and alternating stimuli on CAEP amplitude can be modelled using a quantitative model of latent inhibition. LS deconvolution allows correction for cortical response overlap. The amplitude of the CAEP is sensitive to SOA and stimulus frequency alternation. CAEPs are emerging as an important tool in the objective evaluation of hearing aid and cochlear implant fittings. Responses to closely spaced stimuli provide objective information about integration and inhibition mechanisms in the auditory cortex. Copyright © 2013 International Federation of Clinical Neurophysiology. All rights reserved.

  6. Auditory Evoked Potentials with Different Speech Stimuli: a Comparison and Standardization of Values

    Directory of Open Access Journals (Sweden)

    Didoné, Dayane Domeneghini

    2016-02-01

    Full Text Available Introduction Long Latency Auditory Evoked Potentials (LLAEP with speech sounds has been the subject of research, as these stimuli would be ideal to check individualś detection and discrimination. Objective The objective of this study is to compare and describe the values of latency and amplitude of cortical potentials for speech stimuli in adults with normal hearing. Methods The sample population included 30 normal hearing individuals aged between 18 and 32 years old with ontological disease and auditory processing. All participants underwent LLAEP search using pairs of speech stimuli (/ba/ x /ga/, /ba/ x /da/, and /ba/ x /di/. The authors studied the LLAEP using binaural stimuli at an intensity of 75dBNPS. In total, they used 300 stimuli were used (∼60 rare and 240 frequent to obtain the LLAEP. Individuals received guidance to count the rare stimuli. The authors analyzed latencies of potential P1, N1, P2, N2, and P300, as well as the ampleness of P300. Results The mean age of the group was approximately 23 years. The averages of cortical potentials vary according to different speech stimuli. The N2 latency was greater for /ba/ x /di/ and P300 latency was greater for /ba/ x /ga/. Considering the overall average amplitude, it ranged from 5.35 and 7.35uV for different speech stimuli. Conclusion It was possible to obtain the values of latency and amplitude for different speech stimuli. Furthermore, the N2 component showed higher latency with the / ba / x / di / stimulus and P300 for /ba/ x / ga /.

  7. Enhanced speech perception in noise and cortical auditory evoked potentials in professional musicians.

    Science.gov (United States)

    Meha-Bettison, Kiriana; Sharma, Mridula; Ibrahim, Ronny K; Mandikal Vasuki, Pragati Rao

    2018-01-01

    The current research investigated whether professional musicians outperformed non-musicians on auditory processing and speech-in-noise perception as assessed using behavioural and electrophysiological tasks. Spectro-temporal processing skills were assessed using a psychoacoustic test battery. Speech-in-noise perception was measured using the Listening in Spatialised Noise - Sentences (LiSN-S) test and Cortical Auditory Evoked Potentials (CAEPs) recorded to the speech syllable/da/presented in quiet and in 8-talker babble noise at 0, 5, and 10 dB signal-to-noise ratios (SNRs). Ten professional musicians and 10 non-musicians participated in this study. Musicians significantly outperformed non-musicians in the frequency discrimination task and low-cue condition of the LiSN-S test. Musicians' N1 amplitude showed no difference between 5 dB and 0 dB SNR conditions while non-musicians showed significantly lower N1 amplitude at 0 dB SNR compared to 5 dB SNR. Brain-behaviour correlation for musicians showed a significant association between CAEPs at 5 dB SNR and the low-cue condition of the LiSN-S test at 30-70 ms. Time-frequency analysis indicated musicians had significantly higher alpha power desynchronisation in the 0 dB SNR condition indicating involvement of attention. Through the use of behavioural and electrophysiological data, the results provide converging evidence for improved speech recognition in noise in musicians.

  8. Sensory deprivation regulates the development of the hyperpolarization-activated current in auditory brainstem neurons.

    Science.gov (United States)

    Hassfurth, Benjamin; Magnusson, Anna K; Grothe, Benedikt; Koch, Ursula

    2009-10-01

    Hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels are highly expressed in the superior olivary complex, the primary locus for binaural information processing. This hyperpolarization-activated current (I(h)) regulates the excitability of neurons and enhances the temporally precise analysis of the binaural acoustic cues. By using the whole-cell patch-clamp technique, we examined the properties of I(h) current in neurons of the lateral superior olive (LSO) and the medial nucleus of the trapezoid body (MNTB) before and after hearing onset. Moreover, we tested the hypothesis that I(h) currents are actively regulated by sensory input activity by performing bilateral and unilateral cochlear ablations before hearing onset, resulting in a chronic auditory deprivation. The results show that after hearing onset, I(h) currents are rapidly upregulated in LSO neurons, but change only marginally in neurons of the MNTB. We also found a striking difference in maximal current density, voltage dependence and activation time constant between the LSO and the MNTB in mature-like animals. Following bilateral cochlear ablations before hearing onset, the I(h) currents were scaled up in the LSO and scaled down in the MNTB. Consequently, in the LSO this resulted in a depolarized resting membrane potential and a lower input resistance of these neurons. This type of activity-dependent homeostatic change could thus result in an augmented response to the remaining inputs.

  9. Effect of Different References on Auditory-Evoked Potentials in Children with Cochlear Implants

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    Maojin Liang

    2017-12-01

    Full Text Available Background: Nose reference (NR, mastoid reference (MR, and montage average reference (MAR are usually used in auditory event-related potential (AEP studies with a recently developed reference electrode standardization technique (REST, which may reduce the reference effect. For children with cochlear implants (CIs, auditory deprivation may hinder normal development of the auditory cortex, and the reference effect may be different between CIs and a normal developing group.Methods: Thirteen right-side-CI children were recruited, comprising 7 males and 6 females, ages 2–5 years, with CI usage of ~1 year. Eleven sex- and age-matched healthy children were recruited for normal controls; 1,000 Hz pure tone evoked AEPs were recorded, and the data were re-referenced to NR, left mastoid reference (LMR, which is the opposite side of the implanted cochlear, MAR, and REST. CI artifact and P1–N1 complex (latency, amplitudes at Fz were analyzed.Results: Confirmed P1–N1 complex could be found in Fz using NR, LMR, MAR, and REST with a 128-electrode scalp. P1 amplitude was larger using LMR than MAR and NR, while no statistically significant difference was found between NR and MAR in the CI group; REST had no significant difference with the three other references. In the control group, no statistically significant difference was found with different references. Group difference of P1 amplitude could be found when using MR, MAR, and REST. For P1 latency, no significant difference among the four references was shown, whether in the CI or control group. Group difference in P1 latency could be found in MR and MAR. N1 amplitude in LMR was significantly lower than NR and MAR in the control group. LMR, MAR, and REST could distinguish the difference in the N1 amplitude between the CI and control group. Contralateral MR or MAR was found to be better in differentiating CI children versus controls. No group difference was found for the artifact component

  10. Impact of loudness dependency of auditory evoked potentials on the panic response to CCK-4.

    Science.gov (United States)

    Eser, Daniela; Leicht, Gregor; Baghai, Thomas; Pogarell, Oliver; Schüle, Cornelius; Karch, Susanne; Nothdurfter, Caroline; Rupprecht, Rainer; Mulert, Christoph

    2009-01-01

    Experimental panic induction with cholecystokinin-tetrapeptide (CCK-4) has been established as a model to study the pathophysiology of panic disorder. In line with the serotonin (5-HT)-hypothesis of panic disorder it has been suggested that the panicogenic effects of CCK-4 are mediated in part through the 5-HT system. The analysis of the loudness dependency of the auditory evoked potentials (LDAEP) is a valid non-invasive indicator of central serotonergic activity. We investigated the correlation between LDAEP and behavioral, cardiovascular and neuroendocrine panic responses to CCK-4in 77 healthy volunteers and explored whether differences in LDAEP paralleled subjective panic severity. Behavioral panic responses were measured with the panic symptom scale (PSS). Heart rate and ACTH/cortisol plasma concentrations were assessed concomitantly. LDAEP did not differ between panickers and nonpanickers. Furthermore, LDAEP did not correlate with the behavioral panic response. However, a significant positive correlation between LDAEP and CCK-4 induced HPA-axis activation, which was uniform in panickers and nonpanickers, could be detected. The psychological effects of CCK-4 rather are mediated by neurotransmitters others than the endogenous 5-HT system. However, the extent of the neuroendocrine activation related to the CCK-4 panic provocation was correlated with the LDAEP, thereby suggesting that central 5-HT mechanisms are involved in the HPA-axis activation during this challenge paradigm.

  11. Background noise can enhance cortical auditory evoked potentials under certain conditions

    Science.gov (United States)

    Papesh, Melissa A.; Billings, Curtis J.; Baltzell, Lucas S.

    2017-01-01

    Objective To use cortical auditory evoked potentials (CAEPs) to understand neural encoding in background noise and the conditions under which noise enhances CAEP responses. Methods CAEPs from 16 normal-hearing listeners were recorded using the speech syllable/ba/presented in quiet and speech-shaped noise at signal-to-noise ratios of 10 and 30 dB. The syllable was presented binaurally and monaurally at two presentation rates. Results The amplitudes of N1 and N2 peaks were often significantly enhanced in the presence of low-level background noise relative to quiet conditions, while P1 and P2 amplitudes were consistently reduced in noise. P1 and P2 amplitudes were significantly larger during binaural compared to monaural presentations, while N1 and N2 peaks were similar between binaural and monaural conditions. Conclusions Methodological choices impact CAEP peaks in very different ways. Negative peaks can be enhanced by background noise in certain conditions, while positive peaks are generally enhanced by binaural presentations. Significance Methodological choices significantly impact CAEPs acquired in quiet and in noise. If CAEPs are to be used as a tool to explore signal encoding in noise, scientists must be cognizant of how differences in acquisition and processing protocols selectively shape CAEP responses. PMID:25453611

  12. The effects of stimulus parameters on auditory evoked potentials of Carassius auratus.

    Science.gov (United States)

    Garabon, Jessica R; Higgs, Dennis M

    2017-11-01

    Whole-brain responses to sound are easily measured through auditory evoked potentials (AEP), but it is unclear how differences in experimental parameters affect these responses. The effect of varying parameters is especially unclear in fish studies, the majority of which use simple sound types and then extrapolate to natural conditions. The current study investigated AEPs in goldfish (Carassius auratus) using sounds of different durations (5, 10, and 20 ms) and frequencies (200, 500, 600 and 700 Hz) to test stimulus effects on latency and thresholds. We quantified differences in latency and threshold in comparison to a 10-ms test tone, a duration often used in AEP fish studies. Both response latency and threshold were significantly affected by stimulus duration, with latency patterning suggesting that AEP fires coincident with a decrease in stimulus strength. Response latency was also significantly affected by presentation frequency. These results show that stimulus type has important effects on AEP measures of hearing and call for clearer standards across different measures of AEP. Duration effects also suggest that AEP measures represent summed responses of duration-detecting neural circuit, but more effort is needed to understand the neural drivers of this commonly used technique.

  13. Middle latency auditory evoked responses in normal term infants: a longitudinal study.

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    Rogers, S H; Edwards, D A; Henderson-Smart, D J; Pettigrew, A G

    1989-05-01

    Middle latency auditory evoked responses (MLAERs) were measured in 21 normal term infants, three to five days after birth and then at 6 weeks, 7 months and 1 year of age. A polyphasic waveform was elicited during natural sleep in all infants at each recording session by monaural click stimulation at a rate of 9 per second. A 70 dBHL stimulus was found to be optimal as the MLAER became less well defined when the stimulus intensity approached the threshold hearing level. The first 60 to 70 msec of the waveform was found to be most stable, with decreasing detectability of peaks at longer latencies. There was no change in wave latency or reproducibility of MLAERs recorded during different sleep states. Waves Po and Na showed a significant decrease in latency with increasing stimulus intensity at term and/or 6 weeks of age. This was not evident for the remainder of the waveform. Waves Po, Na, Pa, Nb, Pb and Nc exhibited significant decreases in latency with age, attaining values indistinguishable from adults by 7 months of age.

  14. A Pilot Study on Cortical Auditory Evoked Potentials in Children: Aided CAEPs Reflect Improved High-Frequency Audibility with Frequency Compression Hearing Aid Technology

    National Research Council Canada - National Science Library

    Glista, Danielle; Easwar, Vijayalakshmi; Purcell, David W; Scollie, Susan

    2012-01-01

    Background. This study investigated whether cortical auditory evoked potentials (CAEPs) could reliably be recorded and interpreted using clinical testing equipment, to assess the effects of hearing aid technology on the CAEP...

  15. Auditory Evoked Potentials for the Evaluation of Hearing Sensitivity in Navy Dolphins. Assessment of Hearing Sensitivity in Adult Male Elephant Seals

    National Research Council Canada - National Science Library

    Houser, Dorian S

    2006-01-01

    A custom auditory evoked potential (AEP) system was used to assess the feasibility of rapidly testing the hearing of bottlenose dolphins by tracking the magnitude of the envelope following response (EFR...

  16. Auditory Evoked Potentials for the Evaluation of Hearing Sensitivity in Navy Dolphins. Modification P00002: Assessment of Hearing Sensitivity in Adult Male Elephant Seals

    National Research Council Canada - National Science Library

    Houser, Dorian S

    2006-01-01

    A custom auditory evoked potential (AEP) system was used to assess the feasibility of rapidly testing the hearing of bottlenose dolphins by tracking the magnitude of the envelope following response (EFR...

  17. Delayed visual maturation associated with auditory neuropathy/dyssynchrony.

    Science.gov (United States)

    Aldosari, Mohammed; Mabie, Ann; Husain, Aatif M

    2003-05-01

    Delayed visual maturation is a term used to describe infants who initially seem blind but subsequently have a marked improvement. The mechanism of visual loss and the subsequent improvement remains unknown. Auditory neuropathy/dyssynchrony is a condition of hearing impairment associated with absent or severely abnormal brainstem auditory evoked potentials but normal cochlear functions as measured by otoacoustic emissions. In this report, a 9-month-old infant who had no visual fixation for the first 3 months of life and congenital hearing impairment is described. Her brainstem auditory evoked potential study at 2.5 months of age showed no response to click stimuli presented at 90 dB nHL, whereas her otoacoustic emissions were normal. Subsequently, her vision and hearing improved. A brainstem auditory evoked potential study at 9 months of age showed reproducible waveforms. This case suggests the need for a detailed hearing evaluation of children with delayed visual maturation. Furthermore, this case highlights the need for follow-up brainstem auditory evoked potential testing prior to pursuing any audiologic intervention.

  18. Test-Retest of Long Latency Auditory Evoked Potentials (P300) with Pure Tone and Speech Stimuli.

    Science.gov (United States)

    Perez, Ana Paula; Ziliotto, Karin; Pereira, Liliane Desgualdo

    2017-04-01

    Introduction Long latency auditory evoked potentials, especially P300, have been used for clinical evaluation of mental processing. Many factors can interfere with Auditory Evoked Potential - P300 results, suggesting large intra and inter-subject variations. Objective The objective of the study was to identify the reliability of P3 components (latency and amplitude) over 4-6 weeks and the most stable auditory stimulus with the best test-retest agreement. Methods Ten normal-hearing women participated in the study. Only subjects without auditory processing problems were included. To determine the P3 components, we elicited long latency auditory evoked potential (P300) by pure tone and speech stimuli, and retested after 4-6 weeks using the same parameters. We identified P300 latency and amplitude by waveform subtraction. Results We found lower coefficient of variation values in latency than in amplitude, with less variability analysis when speech stimulus was used. There was no significant correlation in latency measures between pure tone and speech stimuli, and sessions. There was a significant intrasubject correlation between measures of latency and amplitude. Conclusion These findings show that amplitude responses are more robust for the speech stimulus when compared with its pure tone counterpart. The P300 indicated stability for latency and amplitude measures when the test-retest was applied. Reliability was higher for amplitude than for latency, with better agreement when the pure tone stimulus was used. However, further research with speech stimulus is needed to clarify how these stimuli are processed by the nervous system.

  19. Modulation of visually evoked postural responses by contextual visual, haptic and auditory information: a 'virtual reality check'.

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    Georg F Meyer

    Full Text Available Externally generated visual motion signals can cause the illusion of self-motion in space (vection and corresponding visually evoked postural responses (VEPR. These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1 visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2 real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3 visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR.

  20. The Electrically Evoked Auditory Change Complex: Preliminary Results from Nucleus Cochlear Implant Users

    Science.gov (United States)

    Brown, Carolyn J.; Etler, Christine; He, Shuman; O’Brien, Sara; Erenberg, Sheryl; Kim, Jae-Ryong; Dhuldhoya, Aayesha N.; Abbas, Paul J.

    2009-01-01

    Objectives The purpose of this study was to determine if changes in the position of the stimulating electrode in the cochlea could be used to elicit the electrically evoked auditory change complex (EACC) from Nucleus cochlear implant users. Design Nine postlingually deafened adults participated in this study. Each study participant had been using his or her Nucleus CI24 cochlear implant for at least 3 months prior to testing. The speech processor was bypassed and the output of the implanted receiver/stimulator was controlled directly. The stimulus was a 600 ms burst of a biphasic pulse train (1000 pps). In control conditions, the stimulating electrode was held constant and stimulation continued throughout the 600 ms recording interval. In experimental conditions, the EACC was elicited by introducing a change in the stimulating electrode 300 ms after the onset of the pulse train. The EACC was recorded using surface electrodes. Three recordings of 100 sweeps each were obtained for each stimulus condition. Bandpass filtering (1 – 100 Hz) was used to minimize contamination of the recordings by stimulus artifact. Averaged responses were then smoothed using a 40 ms wide boxcar filter and standard peak picking procedures were used to analyze these responses in the time domain. Results In each case, a clear onset response (P1-N1-P2) was recorded. In the experimental conditions, a second evoked potential, the EACC, was also recorded following the change in stimulating electrode. This second response had general morphologic characteristics that were very similar to those of the onset response. Increasing the separation between the two stimulating electrodes in the experimental conditions resulted in a general trend toward increased EACC amplitudes. Conclusions This report describes results of a set of experiments in which the speech processor of the cochlear implant was bypassed and the EACC was recorded in response to a change in stimulating electrode position. EACC

  1. The detection of infant cortical auditory evoked potentials (CAEPs) using statistical and visual detection techniques.

    Science.gov (United States)

    Carter, Lyndal; Golding, Maryanne; Dillon, Harvey; Seymour, John

    2010-05-01

    With the advent of newborn hearing screening programs, the need to verify the fit of hearing aids in young infants has increased. The recording of cortical auditory evoked potentials (CAEPs) for this purpose is quite feasible, but rapid developmental changes that affect response morphology and the presence of electrophysiological noise can make subjective response detection challenging. The purpose of this study was to investigate the effectiveness of an automated statistic versus experienced examiners in detecting the presence of infant CAEPs when stimuli were present and reporting the absence of CAEPs when no stimuli were present. A repeated-measures design was used where infant-generated CAEPs were interpreted by examiners and an automated statistic. There were nine male and five female infants (mean age, 12 mo; SD, 3.4) who completed behavioral and electrophysiological testing using speech-based stimuli. In total, 87 infant CAEPs were recorded to three sensation levels, 10, 20 and 30 dB relative to the behavioral thresholds and to nonstimulus trials. Three examiners were presented with these responses: (1) "in series," where waveforms were presented in order of decreasing stimulus presentation levels, and (2) "nonseries," where waveforms were randomized completely and presented as independent waveforms. The examiners were given no information about the stimulus levels and were asked to determine whether responses to auditory stimulation could be observed and their degree of certainty in making their decision. Data from the CAEP responses were also converted to multiple dependent variables and analyzed using Hotelling's T(2). Results from both methods of response detection were analyzed using a repeated measures ANOVA (analysis of variance) and parameters of signal detection theory known as d-prime (d') and the area under the receiver operating characteristic (ROC) curve. Results showed that as the stimulus level increased, the sensitivity index, d', increased

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

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    Nicolas Guevara

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

  3. 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

  4. Clinical evaluation of cochlear hearing status in dogs using evoked otoacoustic emissions.

    Science.gov (United States)

    Gonçalves, R; McBrearty, A; Pratola, L; Calvo, G; Anderson, T J; Penderis, J

    2012-06-01

    Evoked otoacoustic emission testing is the preferred test in human patients for sensorineural deafness screening in neonates and cochlear outer hair cell function monitoring in adults. This study evaluated evoked otoacoustic emission testing for cochlear function assessment in dogs within a clinical setting. Two populations of anaesthetised dogs were included. In group 1 the evoked otoacoustic emission response was compared to the brainstem auditory evoked response in 10 dogs having hearing assessment. Group 2 comprised 43 presumed normal dogs, in which the suitability of two types of evoked otoacoustic emissions, transient-evoked and distortion product otoacoustic emissions, were evaluated (brainstem auditory evoked response was not performed in this group). Valid transient-evoked otoacoustic emission and distortion-product otoacoustic emission responses were successfully recorded within the clinical setting and correctly identified deaf and hearing ears. Within presumed healthy dogs, normal otoacoustic emission response was demonstrated in more than 80% of dogs using a single, short distortion-product otoacoustic emission run and in 78% of dogs with valid transient-evoked otoacoustic emission responses using a series of three repeated transient-evoked otoacoustic emission short runs. Transient-evoked otoacoustic emission and distortion-product otoacoustic emission testing provided a rapid, non-invasive frequency-specific assessment of cochlear function. Transient-evoked otoacoustic emission and distortion product otoacoustic emission testing is suitable as a screening procedure to detect loss of cochlear function in dogs, although further investigation is needed. © 2012 British Small Animal Veterinary Association.

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

    Science.gov (United States)

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

    2016-01-01

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

  6. Changes in pitch height elicit both language-universal and language-dependent changes in neural representation of pitch in the brainstem and auditory cortex.

    Science.gov (United States)

    Krishnan, Ananthanarayan; Suresh, Chandan H; Gandour, Jackson T

    2017-03-27

    Language experience shapes encoding of pitch-relevant information at both brainstem and cortical levels of processing. Pitch height is a salient dimension that orders pitch from low to high. Herein we investigate the effects of language experience (Chinese, English) in the brainstem and cortex on (i) neural responses to variations in pitch height, (ii) presence of asymmetry in cortical pitch representation, and (iii) patterns of relative changes in magnitude of pitch height between these two levels of brain structure. Stimuli were three nonspeech homologs of Mandarin Tone 2 varying in pitch height only. The frequency-following response (FFR) and the cortical pitch-specific response (CPR) were recorded concurrently. At the Fz-linked T7/T8 site, peak latency of Na, Pb, and Nb decreased with increasing pitch height for both groups. Peak-to-peak amplitude of Na-Pb and Pb-Nb increased with increasing pitch height across groups. A language-dependent effect was restricted to Na-Pb; the Chinese had larger amplitude than the English group. At temporal sites (T7/T8), the Chinese group had larger amplitude, as compared to English, across stimuli, but also limited to the Na-Pb component and right temporal site. In the brainstem, F0 magnitude decreased with increasing pitch height; Chinese had larger magnitude across stimuli. A comparison of CPR and FFR responses revealed distinct patterns of relative changes in magnitude common to both groups. CPR amplitude increased and FFR amplitude decreased with increasing pitch height. Experience-dependent effects on CPR components vary as a function of neural sensitivity to pitch height within a particular temporal window (Na-Pb). Differences between the auditory brainstem and cortex imply distinct neural mechanisms for pitch extraction at both levels of brain structure. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Acoustic Features and Cortical Auditory Evoked Potentials according to Emotional Statues of /u/, /a/, /i/ Vowels.

    Science.gov (United States)

    Kim, Chunhyeok; Lee, Seungwan; Jin, Inki; Kim, Jinsook

    2018-01-05

    Although Ling 6 sounds are often used in the rehabilitation process, its acoustic features have not been fully analyzed and represented in cortical responses. Current study was aimed to analyze acoustic features according to gender and emotional statuses of core vowels of Ling 6 sounds, /u/, /a/, and /i/. Cortical auditory evoked potentials (CAEPs) were also observed in those vowels. Vowel sounds /u/, /a/, and /i/ out of Ling 6 sounds representing low, middle and high frequencies were recorded from normal 20 young adults. The participants watched relevant videos for 4-5 minutes in order for them to sympathize emotions with anger (A), happiness (H), and sadness (S) before producing vowels. And without any emotional salience, neutrally production was performed. The recording was extracted for 500 ms to select pure vowel portion of production. For analysis of CAEP, the latencies and amplitudes of P1, N1, P2, N2, N1-P2 were analyzed. Intensities of /u/, /a/, and /i/ were 61.47, 63.38, and 60.55 dB. The intensities of neutral (N), H, A, S were 60.60, 65.43, 64.21, and 55.75 dB for vowel /u/, vowel /a/ were 61.80, 68.98, 66.50, and 56.23 dB, and vowel /i/ were 59.34, 64.90, 61.90, and 56.05 dB. The statistical significances for vowel and emotion were found but not for gender. The fundamental frequency (F0) of vowels for N, A, H, and S were 168.04, 174.93, 182.72, and 149.76 Hz and the first formant were 743.75, 815.59, 823.32, and 667.62 Hz. The statistical significance of F0 was found by vowel, emotion, and gender. The latencies and amplitudes of CAEP components did not show any statistical significance according to vowel. Ling 6 sounds should be produced consistently in the rehabilitation process for considering their difference of intensities and frequencies according to speaker's emotions and gender. The vowels seemed to be interpreted as tonal stimuli for CAEP components of this study with similar acoustic features among them. Careful selection of materials is

  8. Acceptance of background noise, working memory capacity, and auditory evoked potentials in subjects with normal hearing.

    Science.gov (United States)

    Brännström, K Jonas; Zunic, Edita; Borovac, Aida; Ibertsson, Tina

    2012-01-01

    The acceptable noise level (ANL) test is a method for quantifying the amount of background noise that subjects accept when listening to speech. Large variations in ANL have been seen between normal-hearing subjects and between studies of normal-hearing subjects, but few explanatory variables have been identified. To explore a possible relationship between a Swedish version of the ANL test, working memory capacity (WMC), and auditory evoked potentials (AEPs). ANL, WMC, and AEP were tested in a counterbalanced order across subjects. Twenty-one normal-hearing subjects participated in the study (14 females and 7 males; aged 20-39 yr with an average of 25.7 yr). Reported data consists of age, pure-tone average (PTA), most comfortable level (MCL), background noise level (BNL), ANL (i.e., MCL - BNL), AEP latencies, AEP amplitudes, and WMC. Spearman's rank correlation coefficient was calculated between the collected variables to investigate associations. A principal component analysis (PCA) with Varimax rotation was conducted on the collected variables to explore underlying factors and estimate interactions between the tested variables. Subjects were also pooled into two groups depending on their results on the WMC test, one group with a score lower than the average and one with a score higher than the average. Comparisons between these two groups were made using the Mann-Whitney U-test with Bonferroni correction for multiple comparisons. A negative association was found between ANL and WMC but not between AEP and ANL or WMC. Furthermore, ANL is derived from MCL and BNL, and a significant positive association was found between BNL and WMC. However, no significant associations were seen between AEP latencies and amplitudes and the demographic variables, MCL, and BNL. The PCA identified two underlying factors: One that contained MCL, BNL, ANL, and WMC and another that contained latency for wave Na and amplitudes for waves V and Na-Pa. Using the variables in the first factor

  9. Identification of causal relations between haemodynamic variables, auditory evoked potentials and isoflurane by means of fuzzy logic

    DEFF Research Database (Denmark)

    Jensen, E W; Nebot, A; Caminal, P

    1999-01-01

    The aim of this study was to identify a possible relationship between haemodynamic variables, auditory evoked potentials (AEP) and inspired fraction of isoflurane (ISOFl). Two different models (isoflurane and mean arterial pressure) were identified using the fuzzy inductive reasoning (FIR......) methodology. A fuzzy model is able to identify non-linear and linear components of a causal relationship by means of optimization of information content of available data. Nine young female patients undergoing hysterectomy under general anaesthesia were included. Mean arterial pressure (MAP), heart rate (HR...

  10. Independent component analysis for cochlear implant artifacts attenuation from electrically evoked auditory steady-state response measurements

    Science.gov (United States)

    Deprez, Hanne; Gransier, Robin; Hofmann, Michael; van Wieringen, Astrid; Wouters, Jan; Moonen, Marc

    2018-02-01

    Objective. Electrically evoked auditory steady-state responses (EASSRs) are potentially useful for objective cochlear implant (CI) fitting and follow-up of the auditory maturation in infants and children with a CI. EASSRs are recorded in the electro-encephalogram (EEG) in response to electrical stimulation with continuous pulse trains, and are distorted by significant CI artifacts related to this electrical stimulation. The aim of this study is to evaluate a CI artifacts attenuation method based on independent component analysis (ICA) for three EASSR datasets. Approach. ICA has often been used to remove CI artifacts from the EEG to record transient auditory responses, such as cortical evoked auditory potentials. Independent components (ICs) corresponding to CI artifacts are then often manually identified. In this study, an ICA based CI artifacts attenuation method was developed and evaluated for EASSR measurements with varying CI artifacts and EASSR characteristics. Artifactual ICs were automatically identified based on their spectrum. Main results. For 40 Hz amplitude modulation (AM) stimulation at comfort level, in high SNR recordings, ICA succeeded in removing CI artifacts from all recording channels, without distorting the EASSR. For lower SNR recordings, with 40 Hz AM stimulation at lower levels, or 90 Hz AM stimulation, ICA either distorted the EASSR or could not remove all CI artifacts in most subjects, except for two of the seven subjects tested with low level 40 Hz AM stimulation. Noise levels were reduced after ICA was applied, and up to 29 ICs were rejected, suggesting poor ICA separation quality. Significance. We hypothesize that ICA is capable of separating CI artifacts and EASSR in case the contralateral hemisphere is EASSR dominated. For small EASSRs or large CI artifact amplitudes, ICA separation quality is insufficient to ensure complete CI artifacts attenuation without EASSR distortion.

  11. Regional influence of cocaine on evoked dopamine release in the nucleus accumbens core: A role for the caudal brainstem.

    Science.gov (United States)

    Gerth, Ashlynn I; Alhadeff, Amber L; Grill, Harvey J; Roitman, Mitchell F

    2017-01-15

    Cocaine increases dopamine concentration in the nucleus accumbens through competitive binding to the dopamine transporter (DAT). However, it also increases the frequency of dopamine release events, a finding that cannot be explained by action at the DAT alone. Rather, this effect may be mediated by cocaine-induced modulation of brain regions that project to dopamine neurons. To explore regional contributions of cocaine to dopamine signaling, we administered cocaine to the lateral or fourth ventricles and compared the effects on dopamine release in the nucleus accumbens evoked by electrical stimulation of the ventral tegmental area to that of systemically-delivered cocaine. Stimulation trains caused a sharp rise in dopamine followed by a slower return to baseline. The magnitude of dopamine release ([DA]max) as well as the latency to decay to fifty percent of the maximum (t(1/2); index of DAT activity) by each stimulation train were recorded. All routes of cocaine delivery caused an increase in [DA]max; only systemic cocaine caused an increase in t(1/2). Importantly, these data are the first to show that hindbrain (fourth ventricle)-delivered cocaine modulates phasic dopamine signaling. Fourth ventricular cocaine robustly increased cFos immunoreactivity in the nucleus of the solitary tract (NTS), suggesting a neural substrate for hindbrain cocaine-mediated effects on [DA]max. Together, the data demonstrate that cocaine-induced effects on phasic dopamine signaling are mediated via actions throughout the brain including the hindbrain. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Adriana Silveira Santos

    2009-10-01

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

  13. Transient evoked otoacoustic emissions testing for screening of sensorineural deafness in puppies

    OpenAIRE

    McBrearty, A; Penderis, J

    2011-01-01

    Background: Transient evoked otoacoustic emissions (TEOAE) are widely used for human neonatal deafness screening, but have not been reported for clinical use in dogs. \\ud \\ud Hypothesis/Objectives: To investigate the feasibility of TEOAE testing in conscious puppies and the ability of TEOAE testing to correctly identify deaf and hearing ears, as defined by brainstem auditory evoked response (BAER). \\ud \\ud Animals: Forty puppies from 10 litters. \\ud \\ud Methods: Prospective study on puppies p...

  14. Estabilidade dos potenciais evocados auditivos em indivíduos adultos com audição normal Stability of auditory evoked potentials in adults with normal hearing

    Directory of Open Access Journals (Sweden)

    Carla Gentile Matas

    2011-03-01

    Full Text Available OBJETIVO: Avaliar a estabilidade dos parâmetros dos potenciais evocados auditivos em adultos normais. MÉTODOS: Foram submetidos à avaliação audiológica e eletrofisiológica (potencial evocado auditivo de tronco encefálico - PEATE, potencial evocado auditivo de média latência - PEAML e potencial cognitivo - P300 49 indivíduos normais, de 18 a 40 anos (25 do gênero feminino e 24 do gênero masculino. Realizou-se reavaliação três meses após a avaliação. RESULTADOS: Foram observadas diferenças entre os gêneros na avaliação para as latências das ondas III e V e interpicos I-III e I-V do PEATE e amplitude N2-P3 do P300. Não foram verificadas diferenças significativas para os parâmetros do PEATE, PEAML (latência das ondas Na, Pa e amplitude Na - Pa e P300 (latência da onda P300 entre os resultados obtidos na avaliação e reavaliação. CONCLUSÃO: Exceção feita à amplitude N2-P3, observou-se estabilidade dos parâmetros de PEATE, PEAML e P300 em adultos normais após período de três meses.PURPOSE: To evaluate the stability of parameters of auditory evoked potentials in normal adults. METHODS: Forty-nine normal subjects with ages from 18 to 40 years (25 females and 24 males were submitted to audiological and electrophysiological hearing evaluation (auditory brainstem response - ABR, middle latency response - MLR, and cognitive potential - P300. Subjects were reassessed three months after the initial evaluation. RESULTS: Significant differences were observed between genders regarding the wave latencies III and V and the interpeaks I-III and I-IV of ABR, and the amplitude N2-P3 of the P300. No differences were found between the results of initial and final assessments for the parameters of the ABR, MLR (Na, Pa latencies and Na-Pa amplitude and P300 (P300 latency. CONCLUSION: Except for the N2-P3 amplitude, it was observed stability of the parameters of ABR, MLR and P300 in normal adults after a period of three months.

  15. The effects of neck flexion on cerebral potentials evoked by visual, auditory and somatosensory stimuli and focal brain blood flow in related sensory cortices.

    Science.gov (United States)

    Fujiwara, Katsuo; Kunita, Kenji; Kiyota, Naoe; Mammadova, Aida; Irei, Mariko

    2012-12-03

    A flexed neck posture leads to non-specific activation of the brain. Sensory evoked cerebral potentials and focal brain blood flow have been used to evaluate the activation of the sensory cortex. We investigated the effects of a flexed neck posture on the cerebral potentials evoked by visual, auditory and somatosensory stimuli and focal brain blood flow in the related sensory cortices. Twelve healthy young adults received right visual hemi-field, binaural auditory and left median nerve stimuli while sitting with the neck in a resting and flexed (20° flexion) position. Sensory evoked potentials were recorded from the right occipital region, Cz in accordance with the international 10-20 system, and 2 cm posterior from C4, during visual, auditory and somatosensory stimulations. The oxidative-hemoglobin concentration was measured in the respective sensory cortex using near-infrared spectroscopy. Latencies of the late component of all sensory evoked potentials significantly shortened, and the amplitude of auditory evoked potentials increased when the neck was in a flexed position. Oxidative-hemoglobin concentrations in the left and right visual cortices were higher during visual stimulation in the flexed neck position. The left visual cortex is responsible for receiving the visual information. In addition, oxidative-hemoglobin concentrations in the bilateral auditory cortex during auditory stimulation, and in the right somatosensory cortex during somatosensory stimulation, were higher in the flexed neck position. Visual, auditory and somatosensory pathways were activated by neck flexion. The sensory cortices were selectively activated, reflecting the modalities in sensory projection to the cerebral cortex and inter-hemispheric connections.

  16. 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

    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...

  17. Comparison of conventional averaged and rapid averaged, autoregressive-based extracted auditory evoked potentials for monitoring the hypnotic level during propofol induction

    DEFF Research Database (Denmark)

    Litvan, Héctor; Jensen, Erik W; Galan, Josefina

    2002-01-01

    The extraction of the middle latency auditory evoked potentials (MLAEP) is usually done by moving time averaging (MTA) over many sweeps (often 250-1,000), which could produce a delay of more than 1 min. This problem was addressed by applying an autoregressive model with exogenous input (ARX......) that enables extraction of the auditory evoked potentials (AEP) within 15 sweeps. The objective of this study was to show that an AEP could be extracted faster by ARX than by MTA and with the same reliability....

  18. Comparison of auditory evoked potentials and the A-line ARX Index for monitoring the hypnotic level during sevoflurane and propofol induction

    DEFF Research Database (Denmark)

    Litvan, H; Jensen, E W; Revuelta, M

    2002-01-01

    Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation of the a......Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation...

  19. Speech-induced suppression of evoked auditory fields in children who stutter.

    Science.gov (United States)

    Beal, Deryk S; Quraan, Maher A; Cheyne, Douglas O; Taylor, Margot J; Gracco, Vincent L; De Nil, Luc F

    2011-02-14

    Auditory responses to speech sounds that are self-initiated are suppressed compared to responses to the same speech sounds during passive listening. This phenomenon is referred to as speech-induced suppression, a potentially important feedback-mediated speech-motor control process. In an earlier study, we found that both adults who do and do not stutter demonstrated a reduced amplitude of the auditory M50 and M100 responses to speech during active production relative to passive listening. It is unknown if auditory responses to self-initiated speech-motor acts are suppressed in children or if the phenomenon differs between children who do and do not stutter. As stuttering is a developmental speech disorder, examining speech-induced suppression in children may identify possible neural differences underlying stuttering close to its time of onset. We used magnetoencephalography to determine the presence of speech-induced suppression in children and to characterize the properties of speech-induced suppression in children who stutter. We examined the auditory M50 as this was the earliest robust response reproducible across our child participants and the most likely to reflect a motor-to-auditory relation. Both children who do and do not stutter demonstrated speech-induced suppression of the auditory M50. However, children who stutter had a delayed auditory M50 peak latency to vowel sounds compared to children who do not stutter indicating a possible deficiency in their ability to efficiently integrate auditory speech information for the purpose of establishing neural representations of speech sounds. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Age-related differences in auditory evoked potentials as a function of task modulation during speech-nonspeech processing.

    Science.gov (United States)

    Rufener, Katharina Simone; Liem, Franziskus; Meyer, Martin

    2014-01-01

    Healthy aging is typically associated with impairment in various cognitive abilities such as memory, selective attention or executive functions. Less well observed is the fact that also language functions in general and speech processing in particular seems to be affected by age. This impairment is partly caused by pathologies of the peripheral auditory nervous system and central auditory decline and in some part also by a cognitive decay. This cross-sectional electroencephalography (EEG) study investigates temporally early electrophysiological correlates of auditory related selective attention in young (20-32 years) and older (60-74 years) healthy adults. In two independent tasks, we systematically modulate the subjects' focus of attention by presenting words and pseudowords as targets and white noise stimuli as distractors. Behavioral data showed no difference in task accuracy between the two age samples irrespective of the modulation of attention. However, our work is the first to show that the N1-and the P2 component evoked by speech and nonspeech stimuli are specifically modulated in older adults and young adults depending on the subjects' focus of attention. This finding is particularly interesting in that the age-related differences in AEPs may be reflecting levels of processing that are not mirrored by the behavioral measurements.

  1. Referências anatômicas na cirurgia do implante auditivo de tronco cerebral Anatomical landmarks in auditory brainstem implant surgery

    Directory of Open Access Journals (Sweden)

    Rubens Vuono Brito Neto

    2005-06-01

    Full Text Available O implante auditivo de tronco cerebral é uma opção os pacientes surdos que não têm a integridade das vias auditivas preservada. A cirurgia, por sua complexidade anatômica e funcional, requer treinamento específico em laboratório de anatomia por parte do cirurgião. OBJETIVOS: Estudar a anatomia cirúrgica da cirurgia do implante auditivo de tronco cerebral. FORMA DE ESTUDO: Estudo anatômico. MATERIAL E MÉTODO: Neste estudo dissecamos cadáver fresco preparado com solução corante injetada nas artérias e veias intra-cranianas. O local de inserção do eletrodo do implante auditivo de tronco cerebral foi estudado através do acesso translabiríntico. RESULTADOS: A técnica cirúrgica utilizada para a implantação do eletrodo de tronco cerebral é semelhante à utilizada na remoção do shwannoma vestibular. O complexo de núcleo coclear, composto pelo núcleo coclear ventral e dorsal, é o local para a colocação do eletrodo. O núcleo coclear ventral é o principal núcleo de transmissão de impulsos neurais do VIII par e seus axônios formam a principal via ascendente do nervo coclear. Tanto o núcleo ventral como o dorsal não são visíveis durante a cirurgia e sua localização depende de identificação de estruturas anatômicas adjacentes. CONCLUSÃO: A região de implantação do eletrodo do implante auditivo de tronco cerebral apresenta referências anatômicas que permitem sua fácil identificação durante a cirurgia.Auditory brainstem implant (ABI is an option for deaf patients who do not have the whole auditory pathways preserved. The surgery, because of its anatomical and functional complexity, requires specific training of the surgeon in an anatomy lab. AIM: To study the surgical anatomy of the auditory brainstem implant surgery. STUDY DESIGN: Anatomic study. MATERIAL AND METHOD: In the present study, we dissected a fresh cadaver prepared with a dye solution injected into the arteries and intracranial veins. The

  2. Multimodality evoked potentials in HTLV-I associated myelopathy.

    OpenAIRE

    Kakigi, R; Shibasaki, H; Kuroda, Y; Endo, C; Oda, K; Ikeda, A; Hashimoto, K

    1988-01-01

    Multimodality evoked potentials (EPs) consisting of somatosensory EPs (SEPs), visual EPs (VEPs) and brainstem auditory EPs (BAEPs) were studied in 16 cases with HTLV-I associated myelopathy (HAM). Median nerve SEPs were normal in all cases. In posterior tibial nerve SEPs, the potential recorded at the 12th thoracic spinal process was normal in every case but cortical components were significantly prolonged in 10 cases, although five of these showed no sensory impairment. BAEPs were normal in ...

  3. [The use of short-latency auditory evoked potentials in the diagnosis of acoustic neurinomas].

    Science.gov (United States)

    Baliazin, V A; Bakhtin, O M; Bu Khaled, Kh E; Filatova, V S

    1993-01-01

    The short-latent acoustic evoked potentials in patients with unilateral neurosensory hypoacusis due to the tumor of the acoustic nerve or other etiology were recorded. It was found that the patients had no potential in the diseased area in monaural sound stimulation, but binaural sound stimulation enabled these potentials to be recorded. With this, the short-latent acoustic evoked potentials in patients with verified neurinoma showed a reduction in the third wave to the point of its disappearance. Those in patients whose neurosensory hypoacusis were unassociated with the development of neoplasms in the area of the acoustic nerve involve the third wave whose magnitude did not differ from that recorded in the examinees with otologically normal hearing. The authors propose to measure the third wave of the short-latent acoustic evoked potential recorded in binaural sound stimulation as a possible screening of persons at a high risk for neurinoma among patients with unilateral neurosensory hypoacusis.

  4. Gap detection measured with electrically evoked auditory event-related potentials and speech-perception abilities in children with auditory neuropathy spectrum disorder.

    Science.gov (United States)

    He, Shuman; Grose, John H; Teagle, Holly F B; Woodard, Jennifer; Park, Lisa R; Hatch, Debora R; Buchman, Craig A

    2013-01-01

    This study aimed (1) to investigate the feasibility of recording the electrically evoked auditory event-related potential (eERP), including the onset P1-N1-P2 complex and the electrically evoked auditory change complex (EACC) in response to temporal gaps, in children with auditory neuropathy spectrum disorder (ANSD); and (2) to evaluate the relationship between these measures and speech-perception abilities in these subjects. Fifteen ANSD children who are Cochlear Nucleus device users participated in this study. For each subject, the speech-processor microphone was bypassed and the eERPs were elicited by direct stimulation of one mid-array electrode (electrode 12). The stimulus was a train of biphasic current pulses 800 msec in duration. Two basic stimulation conditions were used to elicit the eERP. In the no-gap condition, the entire pulse train was delivered uninterrupted to electrode 12, and the onset P1-N1-P2 complex was measured relative to the stimulus onset. In the gapped condition, the stimulus consisted of two pulse train bursts, each being 400 msec in duration, presented sequentially on the same electrode and separated by one of five gaps (i.e., 5, 10, 20, 50, and 100 msec). Open-set speech-perception ability of these subjects with ANSD was assessed using the phonetically balanced kindergarten (PBK) word lists presented at 60 dB SPL, using monitored live voice in a sound booth. The eERPs were recorded from all subjects with ANSD who participated in this study. There were no significant differences in test-retest reliability, root mean square amplitude or P1 latency for the onset P1-N1-P2 complex between subjects with good (>70% correct on PBK words) and poorer speech-perception performance. In general, the EACC showed less mature morphological characteristics than the onset P1-N1-P2 response recorded from the same subject. There was a robust correlation between the PBK word scores and the EACC thresholds for gap detection. Subjects with poorer speech

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

    Science.gov (United States)

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

    2010-10-01

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

  6. Auditory Brainstem and Middle Latency Responses Measured Pre- and Posttreatment for Hyperacusic Hearing-Impaired Persons Successfully Treated to Improve Sound Tolerance and to Expand the Dynamic Range for Loudness: Case Evidence.

    Science.gov (United States)

    Formby, Craig; Korczak, Peggy; Sherlock, LaGuinn P; Hawley, Monica L; Gold, Susan

    2017-02-01

    In this report of three cases, we consider electrophysiologic measures from three hyperacusic hearing-impaired individuals who, prior to treatment to expand their dynamic ranges for loudness, were problematic hearing aid candidates because of their diminished sound tolerance and reduced dynamic ranges. Two of these individuals were treated with structured counseling combined with low-level broadband sound therapy from bilateral sound generators and the third case received structured counseling in combination with a short-acting placebo sound therapy. Each individual was highly responsive to his or her assigned treatment as revealed by expansion of the dynamic range by at least 20 dB at one or more frequencies posttreatment. Of specific interest in this report are their latency and amplitude measures taken from tone burst-evoked auditory brainstem response (ABR) and cortically derived middle latency response (MLR) recordings, measured as a function of increasing loudness at 500 and 2,000 Hz pre- and posttreatment. The resulting ABR and MLR latency and amplitude measures for each case are considered here in terms of pre- and posttreatment predictions. The respective pre- and posttreatment predictions anticipated larger pretreatment response amplitudes and shorter pretreatment response latencies relative to typical normal control values and smaller normative-like posttreatment response amplitudes and longer posttreatment response latencies relative to the corresponding pretreatment values for each individual. From these results and predictions, we conjecture about the neural origins of the hyperacusis conditions (i.e., brainstem versus cortical) and the neuronal sites responsive to treatment. The only consistent finding in support of the pre- and posttreatment predictions and, thus, the strongest index of hyperacusis and positive treatment-related effects was measured for MLR latency responses for wave Pa at 2,000 Hz. Other response indices, including ABR wave V

  7. Effects of rotation on the sleep state-dependent midlatency auditory evoked P50 potential in the human

    Science.gov (United States)

    Dornhoffer, John L.; Mamiya, N.; Bray, P.; Skinner, Robert D.; Garcia-Rill, Edgar

    2002-01-01

    Sopite syndrome, characterized by loss of initiative, sensitivity to normally innocuous sensory stimuli, and impaired concentration amounting to a sensory gating deficit, is commonly associated with Space Motion Sickness (SMS). The amplitude of the P50 potential is a measure of level of arousal, and a paired-stimulus paradigm can be used to measure sensory gating. We used the rotary chair to elicit the sensory mismatch that occurs with SMS by overstimulating the vestibular apparatus. The effects of rotation on the manifestation of the P50 midlatency auditory evoked response were then assessed as a measure of arousal and distractibility. Results showed that rotation-induced motion sickness produced no change in the level of arousal but did produce a significant deficit in sensory gating, indicating that some of the attentional and cognitive deficits observed with SMS may be due to distractibility induced by decreased habituation to repetitive stimuli.

  8. Assessment of Electrically Evoked Auditory Brain Stem Response of 30 Implanted Patients With Nucleus Multichannel Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Dr. Soqrat Faghihzadeh

    2001-05-01

    Full Text Available Methods and Materials: Investigation of electrically evoked auditory brain stem response (EABR is a new issue, especially in implanted patients. Experiments were performed in C.I Center of Iranian Institute for Science and research expansion,1996 on 30 implanted patients with 22 spectra and MSP cochlear implant system and 30 normal subjects with the range of 3-33 years. Findings: I- EABR was obtained in the implanted patients. 2- Absolute latency of EABR waves is 1-1.5 ms shorter than ABR waves ‘P<0.05. 3-Absolute latency of wave V decreases as a function of electric stimulus magnitude (P<0.05. 4- No significant difference was observed in IPL Ill-V between ABR and EABR.

  9. Gating of the vertex somatosensory and auditory evoked potential P50 and the correlation to skin conductance orienting response in healthy men

    DEFF Research Database (Denmark)

    Arnfred, S M; Eder, D N; Hemmingsen, R P

    2001-01-01

    A defect in auditory evoked potential (AEP) P50 gating supports the theory of information-processing deficits in schizophrenia. The relationship between gating of the mid-latency evoked potentials (EP) in the somatosensory and the auditory modalities has not been studied together before. In schiz......A defect in auditory evoked potential (AEP) P50 gating supports the theory of information-processing deficits in schizophrenia. The relationship between gating of the mid-latency evoked potentials (EP) in the somatosensory and the auditory modalities has not been studied together before....... In schizophrenia, we might expect the processing deficits to act on multiple modalities. We have examined the gating of median nerve somatosensory EP (SEP) following paired stimulation identical to the AEP P50 gating paradigm using interstimulus intervals (ISI) of 500, 750 and 1000 ms and the correlation of gating...... to the skin conductance orienting response (SCOR) in 20 healthy men. We measured mid-latency vertex components (SEP: P50, N65, P85 and N100; AEP: P30, N45, P50 and N80). The gating was most pronounced at ISI 500 ms where the SEP P50 and N100 gating were 0.59 and 0.37, respectively, as compared to a gating...

  10. Comparison of auditory evoked potentials and the A-line ARX Index for monitoring the hypnotic level during sevoflurane and propofol induction

    DEFF Research Database (Denmark)

    Litvan, H; Jensen, E W; Revuelta, M

    2002-01-01

    Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation of the a...

  11. Comparison of conventional averaged and rapid averaged, autoregressive-based extracted auditory evoked potentials for monitoring the hypnotic level during propofol induction

    DEFF Research Database (Denmark)

    Litvan, Héctor; Jensen, Erik W; Galan, Josefina

    2002-01-01

    The extraction of the middle latency auditory evoked potentials (MLAEP) is usually done by moving time averaging (MTA) over many sweeps (often 250-1,000), which could produce a delay of more than 1 min. This problem was addressed by applying an autoregressive model with exogenous input (ARX) that...

  12. Intensity dependence of auditory evoked dipole source activity in polydrug ecstasy users: evidence from an 18 months longitudinal study.

    Science.gov (United States)

    Daumann, Jörg; Till, Bianca; Fischermann, Thomas; Rezk, Markus; Gouzoulis-Mayfrank, Euphrosyne

    2006-03-01

    Numerous animal studies have been able to demonstrate neurotoxic damage to central serotonergic systems after exposure to 3,4-methylenedioxymethamphetamine (MDMA, ecstasy). It has been suggested that a high loudness dependence of auditory evoked potentials (LDAEP) and, particularly, of the tangential N1/P2 source activity is associated with a low functioning of serotonergic activity. Therefore, the LDAEP may be used as a non-invasive indicator for a possible neurotoxic damage caused by the long-term use of ecstasy in recreational users. We recorded auditory evoked potentials (AEP) with a passive listening paradigm in 18 polydrug ecstasy users at baseline (t1) and after 18 months (t2). Several aspects of ecstasy use, such as frequency of use, cumulative lifetime dose or period of abstinence were associated with the LDAEP for several tangential dipoles at both measuring times. However, we failed to demonstrate any significant relationship between drug use reported at follow-up and AEP changes from baseline to follow-up. Despite some incertitude these data suggest, yet do not unambiguously con.rm, the hypothesis that abstinent ecstasy users present with diminished central serotonergic activity. This feature of information processing is potentially related to the neurotoxic potential of ecstasy. However, alternative interpretations of these data refer to possible preexisting traits and the potential impact of other illicit drugs, particularly amphetamine, since ecstasy users typically exhibit polydrug use patterns. Thus, further research with larger sample sizes and prospective study designs are needed to definitively establish a causative link between ecstasy use and neurotoxicity-related dysfunctions in sensory processing.

  13. Auditory and visual P300 evoked potentials do not predict response to valproate treatment of aggression in patients with borderline and antisocial personality disorders.

    Science.gov (United States)

    Reeves, Roy R; Struve, Frederick A; Patrick, Gloria

    2005-01-01

    In this study of patients with borderline personality disorder (BPD) or antisocial personality disorder (ASPD) hospitalized because of aggressive behavior, auditory and visual P300 evoked potentials were obtained prior to treatment with valproate. Eight ASPD patients (8 males, 0 females) and 11 BPD patients (2 males, 9 females) showed improvement, while in 7 patients with ASPD (7 males, 0 females) and 10 patients with BPD (2 males, 8 females), aggression was not improved. Differences in auditory and visual P300 latencies and amplitudes were not significant for either diagnosis, or for both diagnoses combined. These findings suggest that auditory or visual P300 evoked potentials may not be useful for predicting response of aggressive behavior to valproate treatment in patients with BPD or ASPD.

  14. Effects of continuous conditioning noise and light on the auditory- and visual-evoked potentials of the guinea pig.

    Science.gov (United States)

    Goksoy, Cuneyt; Demirtas, Serdar; Ates, Kahraman

    2005-11-02

    Neurophysiological studies aiming to explore how the brain integrates information from different brain regions are increasing in the literature. The aim of the present study is to explore intramodal (binaural, binocular) and intermodal (audio-visual) interactions in the guinea pig brain through the observation of changes in evoked potentials by generalized continuous background activity. Seven chronically prepared animals were used in the study and the recordings were made as they were awake. Epidural electrodes were implanted to the skulls by using stereotaxic methods. Continuous light for retinal or continuous white noise for cochlear receptors were used as continuous conditioning stimuli for generalized stimulation. To evoke auditory or visual potentials, click or flash were used as transient imperative stimuli. The study data suggest that (a) white noise applied to one ear modifies the response to click in the contralateral ear which is a binaural interaction; (b) continuous light applied to one eye modifies the response to flash applied to the contralateral eye which is interpreted as a binocular interaction; (c) regardless of the application side, white noise similarly modified the response to flash applied to the either eye connoting a nonspecific effect of white noise on vision, independent from spatial hearing mechanisms; (d) on the other hand, continuous light, in either eye, did not affect the response to click applied to any ear, reminding a 'one-way' interaction that continuous aural stimulation affects visual response.

  15. The auditory cortex hosts network nodes influential for emotion processing: An fMRI study on music-evoked fear and joy.

    Science.gov (United States)

    Koelsch, Stefan; Skouras, Stavros; Lohmann, Gabriele

    2018-01-01

    Sound is a potent elicitor of emotions. Auditory core, belt and parabelt regions have anatomical connections to a large array of limbic and paralimbic structures which are involved in the generation of affective activity. However, little is known about the functional role of auditory cortical regions in emotion processing. Using functional magnetic resonance imaging and music stimuli that evoke joy or fear, our study reveals that anterior and posterior regions of auditory association cortex have emotion-characteristic functional connectivity with limbic/paralimbic (insula, cingulate cortex, and striatum), somatosensory, visual, motor-related, and attentional structures. We found that these regions have remarkably high emotion-characteristic eigenvector centrality, revealing that they have influential positions within emotion-processing brain networks with "small-world" properties. By contrast, primary auditory fields showed surprisingly strong emotion-characteristic functional connectivity with intra-auditory regions. Our findings demonstrate that the auditory cortex hosts regions that are influential within networks underlying the affective processing of auditory information. We anticipate our results to incite research specifying the role of the auditory cortex-and sensory systems in general-in emotion processing, beyond the traditional view that sensory cortices have merely perceptual functions.

  16. Linear combination of auditory steady-state responses evoked by co-modulated tones

    DEFF Research Database (Denmark)

    Guérit, François; Marozeau, Jeremy; Epp, Bastian

    2017-01-01

    Up to medium intensities and in the 80–100-Hz region, the auditory steady-state response (ASSR) to a multi-tone carrier is commonly considered to be a linear sum of the dipoles from each tone specific ASSR generator. Here, this hypothesis was investigated when a unique modulation frequency is used...... for all carrier components. Listeners were presented with a co-modulated dual-frequency carrier (1 and 4 kHz), from which the modulator starting phase Ui of the 1-kHz component was systematically varied. The results support the hypothesis of a linear superposition of the dipoles originating from different...

  17. Assessment of hearing threshold in adults with hearing loss using an automated system of cortical auditory evoked potential detection

    Directory of Open Access Journals (Sweden)

    Alessandra Spada Durante

    Full Text Available Abstract Introduction: The use of hearing aids by individuals with hearing loss brings a better quality of life. Access to and benefit from these devices may be compromised in patients who present difficulties or limitations in traditional behavioral audiological evaluation, such as newborns and small children, individuals with auditory neuropathy spectrum, autism, and intellectual deficits, and in adults and the elderly with dementia. These populations (or individuals are unable to undergo a behavioral assessment, and generate a growing demand for objective methods to assess hearing. Cortical auditory evoked potentials have been used for decades to estimate hearing thresholds. Current technological advances have lead to the development of equipment that allows their clinical use, with features that enable greater accuracy, sensitivity, and specificity, and the possibility of automated detection, analysis, and recording of cortical responses. Objective: To determine and correlate behavioral auditory thresholds with cortical auditory thresholds obtained from an automated response analysis technique. Methods: The study included 52 adults, divided into two groups: 21 adults with moderate to severe hearing loss (study group; and 31 adults with normal hearing (control group. An automated system of detection, analysis, and recording of cortical responses (HEARLab® was used to record the behavioral and cortical thresholds. The subjects remained awake in an acoustically treated environment. Altogether, 150 tone bursts at 500, 1000, 2000, and 4000 Hz were presented through insert earphones in descending-ascending intensity. The lowest level at which the subject detected the sound stimulus was defined as the behavioral (hearing threshold (BT. The lowest level at which a cortical response was observed was defined as the cortical electrophysiological threshold. These two responses were correlated using linear regression. Results: The cortical

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

    Science.gov (United States)

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

    2016-01-01

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

  19. [Fitting hearing aids in early childhood based on auditory evoked potentials in steady states].

    Science.gov (United States)

    Zenker Castro, F; Fernández Belda, R; Barajas de Prat, J J

    2006-11-01

    The purpose of the Newborn Hearing Screening Program is to achieve early. Identification and appropriate intervention for hearing loss. Hearing aids are the most frequent intervention for deafness. Paediatric specific clinical protocols for fitting hearing aids always recommend accurate characterisation of hearing thresholds in newborns. In this sense, electrophysiological procedures are specially indicated in determined hearing sensibility from the first age of life since it is an objective and reliable procedure. 20 normal hearing subject and 17 hearing loss subjects participated in this study. Auditory Steady State Responses (ASSR) were obtained from all of them. Hearing aid fitting was established from the electrophysiological responses. Dynamic range, gain, compression ratio and maximum output of the hearing aid were obtained from the intensity amplitude function of the ASSR. The procedure discussed in this study is specially indicated in newborns and very young children in which other test are not suitable.

  20. A machine learning approach for distinguishing age of infants using auditory evoked potentials.

    Science.gov (United States)

    Ravan, Maryam; Reilly, James P; Trainor, Laurel J; Khodayari-Rostamabad, Ahmad

    2011-11-01

    To develop a high performance machine learning (ML) approach for predicting the age and consequently the state of brain development of infants, based on their event related potentials (ERPs) in response to an auditory stimulus. The ERP responses of twenty-nine 6-month-olds, nineteen 12-month-olds and 10 adults to an auditory stimulus were derived from electroencephalogram (EEG) recordings. The most relevant wavelet coefficients corresponding to the first- and second-order moment sequences of the ERP signals were then identified using a feature selection scheme that made no a priori assumptions about the features of interest. These features are then fed into a classifier for determination of age group. We verified that ERP data could yield features that discriminate the age group of individual subjects with high reliability. A low dimensional representation of the selected feature vectors show significant clustering behavior corresponding to the subject age group. The performance of the proposed age group prediction scheme was evaluated using the leave-one-out cross validation method and found to exceed 90% accuracy. This study indicates that ERP responses to an acoustic stimulus can be used to predict the age and consequently the state of brain development of infants. This study is of fundamental scientific significance in demonstrating that a machine classification algorithm with no a priori assumptions can classify ERP responses according to age and with further work, potentially provide useful clues in the understanding of the development of the human brain. A potential clinical use for the proposed methodology is the identification of developmental delay: an abnormal condition may be suspected if the age estimated by the proposed technique is significantly less than the chronological age of the subject. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  1. Unexpected Improvement of Hand Motor Function with a Left Temporoparietal Low-Frequency Repetitive Transcranial Magnetic Stimulation Regime Suppressing Auditory Hallucinations in a Brainstem Chronic Stroke Patient

    Directory of Open Access Journals (Sweden)

    Fanny Thomas

    2017-11-01

    Full Text Available We here report paradoxical hand function recovery in a 61-year-old male tetra-paretic chronic patient following a stroke of the brainstem (with highly degraded right and abolished left-hand finger flexion/extension disabling him to manipulate objects who experienced insidious auditory hallucinations (AHs 4 years after such event. Symptomatic treatment for AHs was provided with periodical double sessions of low-frequency repetitive transcranial magnetic stimulation (rTMS (daily 1 Hz, 2 × 1,200 pulses interleaved by 1 h interval delivered to the left temporoparietal junction across two periods of 5 and 3 weeks, respectively. At the end of each stimulation period, AHs disappeared completely. Most surprisingly and totally unexpectedly, the patient experienced beneficial improvements of long-lasting impairments in his right-hand function. Detailed examination of onset and offset of rTMS stimulation regimes strongly suggests a temporal relation with the remission and re-appearance of AHs and also with a fragile but clinically meaningful improvements of right (but not left hand function contingent to the accrual of stimulation sessions. On the basis of post-recovery magnetic resonance imaging structural and functional evidence, mechanistic hypotheses that could subtend such unexpected motor recovery are critically discussed.

  2. Least-squares (LS) deconvolution of a series of overlapping cortical auditory evoked potentials: a simulation and experimental study.

    Science.gov (United States)

    Bardy, Fabrice; Van Dun, Bram; Dillon, Harvey; Cowan, Robert

    2014-08-01

    To evaluate the viability of disentangling a series of overlapping 'cortical auditory evoked potentials' (CAEPs) elicited by different stimuli using least-squares (LS) deconvolution, and to assess the adaptation of CAEPs for different stimulus onset-asynchronies (SOAs). Optimal aperiodic stimulus sequences were designed by controlling the condition number of matrices associated with the LS deconvolution technique. First, theoretical considerations of LS deconvolution were assessed in simulations in which multiple artificial overlapping responses were recovered. Second, biological CAEPs were recorded in response to continuously repeated stimulus trains containing six different tone-bursts with frequencies 8, 4, 2, 1, 0.5, 0.25 kHz separated by SOAs jittered around 150 (120-185), 250 (220-285) and 650 (620-685) ms. The control condition had a fixed SOA of 1175 ms. In a second condition, using the same SOAs, trains of six stimuli were separated by a silence gap of 1600 ms. Twenty-four adults with normal hearing (<20 dB HL) were assessed. Results showed disentangling of a series of overlapping responses using LS deconvolution on simulated waveforms as well as on real EEG data. The use of rapid presentation and LS deconvolution did not however, allow the recovered CAEPs to have a higher signal-to-noise ratio than for slowly presented stimuli. The LS deconvolution technique enables the analysis of a series of overlapping responses in EEG. LS deconvolution is a useful technique for the study of adaptation mechanisms of CAEPs for closely spaced stimuli whose characteristics change from stimulus to stimulus. High-rate presentation is necessary to develop an understanding of how the auditory system encodes natural speech or other intrinsically high-rate stimuli.

  3. Least-squares (LS) deconvolution of a series of overlapping cortical auditory evoked potentials: a simulation and experimental study

    Science.gov (United States)

    Bardy, Fabrice; Van Dun, Bram; Dillon, Harvey; Cowan, Robert

    2014-08-01

    Objective. To evaluate the viability of disentangling a series of overlapping ‘cortical auditory evoked potentials’ (CAEPs) elicited by different stimuli using least-squares (LS) deconvolution, and to assess the adaptation of CAEPs for different stimulus onset-asynchronies (SOAs). Approach. Optimal aperiodic stimulus sequences were designed by controlling the condition number of matrices associated with the LS deconvolution technique. First, theoretical considerations of LS deconvolution were assessed in simulations in which multiple artificial overlapping responses were recovered. Second, biological CAEPs were recorded in response to continuously repeated stimulus trains containing six different tone-bursts with frequencies 8, 4, 2, 1, 0.5, 0.25 kHz separated by SOAs jittered around 150 (120-185), 250 (220-285) and 650 (620-685) ms. The control condition had a fixed SOA of 1175 ms. In a second condition, using the same SOAs, trains of six stimuli were separated by a silence gap of 1600 ms. Twenty-four adults with normal hearing (EEG data. The use of rapid presentation and LS deconvolution did not however, allow the recovered CAEPs to have a higher signal-to-noise ratio than for slowly presented stimuli. The LS deconvolution technique enables the analysis of a series of overlapping responses in EEG. Significance. LS deconvolution is a useful technique for the study of adaptation mechanisms of CAEPs for closely spaced stimuli whose characteristics change from stimulus to stimulus. High-rate presentation is necessary to develop an understanding of how the auditory system encodes natural speech or other intrinsically high-rate stimuli.

  4. Comparison of auditory evoked potentials and the A-line ARX Index for monitoring the hypnotic level during sevoflurane and propofol induction

    DEFF Research Database (Denmark)

    Litvan, H; Jensen, E W; Revuelta, M

    2002-01-01

    Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation of the a......Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation...... of the appropriate signals of the AEP could be difficult to perform during the anesthesia procedure. This problem was addressed by defining an index which reflected the peak amplitudes and latencies of the AEP, developed to improve the clinical interpretation of the AEP. This index was defined as the A-line Arx...

  5. Auditory-evoked cortical activity: contribution of brain noise, phase locking, and spectral power.

    Science.gov (United States)

    Harris, Kelly C; Vaden, Kenneth I; Dubno, Judy R

    2014-09-01

    The N1-P2 is an obligatory cortical response that can reflect the representation of spectral and temporal characteristics of an auditory stimulus. Traditionally,mean amplitudes and latencies of the prominent peaks in the averaged response are compared across experimental conditions. Analyses of the peaks in the averaged response only reflect a subset of the data contained within the electroencephalogram(EEG) signal. We used single-trial analyses techniques to identify the contribution of brain noise,neural synchrony, and spectral power to the generation of P2 amplitude and how these variables may change across age group. This information is important for appropriate interpretation of event-related potentials (ERPs) results and in understanding of age-related neural pathologies. EEG was measured from 25 younger and 25 older normal hearing adults. Age-related and individual differences in P2 response amplitudes, and variability in brain noise, phase locking value (PLV), and spectral power (4-8 Hz) were assessed from electrode FCz. Model testing and linear regression were used to determine the extent to which brain noise, PLV, and spectral power uniquely predicted P2 amplitudes and varied by age group. Younger adults had significantly larger P2 amplitudes, PLV, and power compared to older adults. Brain noise did not differ between age groups. The results of regression testing revealed that brain noise and PLV, but not spectral power were unique predictors of P2 amplitudes. Model fit was significantly better in younger than in older adults. ERP analyses are intended to provide a better understanding of the underlying neural mechanisms that contribute to individual and group differences in behavior. The current results support that age-related declines in neural synchrony contribute to smaller P2 amplitudes in older normal hearing adults. Based on our results, we discuss potential models in which differences in neural synchrony and brain noise can account for

  6. Mild Cognitive Impairment Is Characterized by Deficient Brainstem and Cortical Representations of Speech.

    Science.gov (United States)

    Bidelman, Gavin M; Lowther, Jill E; Tak, Sunghee H; Alain, Claude

    2017-03-29

    Mild cognitive impairment (MCI) is recognized as a transitional phase in the progression toward more severe forms of dementia and is an early precursor to Alzheimer's disease. Previous neuroimaging studies reveal that MCI is associated with aberrant sensory-perceptual processing in cortical brain regions subserving auditory and language function. However, whether the pathophysiology of MCI extends to speech processing before conscious awareness (brainstem) is unknown. Using a novel electrophysiological approach, we recorded both brainstem and cortical speech-evoked brain event-related potentials (ERPs) in older, hearing-matched human listeners who did and did not present with subtle cognitive impairment revealed through behavioral neuropsychological testing. We found that MCI was associated with changes in neural speech processing characterized as hypersensitivity (larger) brainstem and cortical speech encoding in MCI compared with controls in the absence of any perceptual speech deficits. Group differences also interacted with age differentially across the auditory pathway; brainstem responses became larger and cortical ERPs smaller with advancing age. Multivariate classification revealed that dual brainstem-cortical speech activity correctly identified MCI listeners with 80% accuracy, suggesting its application as a biomarker of early cognitive decline. Brainstem responses were also a more robust predictor of individuals' MCI severity than cortical activity. Our findings suggest that MCI is associated with poorer encoding and transfer of speech signals between functional levels of the auditory system and advance the pathophysiological understanding of cognitive aging by identifying subcortical deficits in auditory sensory processing mere milliseconds (declines in communication skills. Whether MCI pathophysiology extends below cerebral cortex to affect speech processing before conscious awareness (brainstem) is unknown. By recording neuroelectric brain activity to

  7. Optic and auditory pathway dysfunction in demyelinating neuropathies.

    Science.gov (United States)

    Knopp, M; Leese, R J; Martin-Lamb, D; Rajabally, Y A

    2014-07-01

    The involvement of optic and auditory pathways has rarely been studied in demyelinating polyneuropathies. We here aimed to study this further in a cohort of patients with acquired and gentic demyelinating neuropathy. We studied eight patients with hereditary neuropathy with liability to pressure palsies (HNPP), six with Charcot-Marie-Tooth disease type 1A (CMT1A), ten with chronic inflammatory demyelinating polyneuropathy (CIDP) and seven with antimyelin-associated glycoprotein (MAG) neuropathy using visual evoked potentials and brainstem auditory evoked potentials. Optic pathway dysfunction was detected in 6/7 anti-MAG neuropathy patients, about half of those with CIDP and HNPP, but only in 1/6 patients with CMT1A. Peripheral auditory nerve dysfunction appeared common in all groups except HNPP. Brainstem involvement was exceptional in all groups. We conclude optic nerve involvement may be frequent in all demyelinating polyneuropathies, particularly anti-MAG neuropathy, except in CMT1A. Peripheral auditory nerves may be spared in HNPP possibly due to absence of local compression. Evidence for central brainstem pathology appeared infrequent in all four studied neuropathies. This study suggests that acquired and genetic demyelinating polyneuropathies may be associated with optic and auditory nerve involvement, which may contribute to neurological disability, and require greater awareness. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Hearing in the Juvenile Green Sea Turtle (Chelonia mydas): A Comparison of Underwater and Aerial Hearing Using Auditory Evoked Potentials

    Science.gov (United States)

    Piniak, Wendy E. D.; Mann, David A.; Harms, Craig A.; Jones, T. Todd; Eckert, Scott A.

    2016-01-01

    Sea turtles spend much of their life in aquatic environments, but critical portions of their life cycle, such as nesting and hatching, occur in terrestrial environments, suggesting that it may be important for them to detect sounds in both air and water. In this study we compared underwater and aerial hearing sensitivities in five juvenile green sea turtles (Chelonia mydas) by measuring auditory evoked potential responses to tone pip stimuli. Green sea turtles detected acoustic stimuli in both media, responding to underwater stimuli between 50 and 1600 Hz and aerial stimuli between 50 and 800 Hz, with maximum sensitivity between 200 and 400 Hz underwater and 300 and 400 Hz in air. When underwater and aerial hearing sensitivities were compared in terms of pressure, green sea turtle aerial sound pressure thresholds were lower than underwater thresholds, however they detected a wider range of frequencies underwater. When thresholds were compared in terms of sound intensity, green sea turtle sound intensity level thresholds were 2–39 dB lower underwater particularly at frequencies below 400 Hz. Acoustic stimuli may provide important environmental cues for sea turtles. Further research is needed to determine how sea turtles behaviorally and physiologically respond to sounds in their environment. PMID:27741231

  9. Hearing in the Juvenile Green Sea Turtle (Chelonia mydas: A Comparison of Underwater and Aerial Hearing Using Auditory Evoked Potentials.

    Directory of Open Access Journals (Sweden)

    Wendy E D Piniak

    Full Text Available Sea turtles spend much of their life in aquatic environments, but critical portions of their life cycle, such as nesting and hatching, occur in terrestrial environments, suggesting that it may be important for them to detect sounds in both air and water. In this study we compared underwater and aerial hearing sensitivities in five juvenile green sea turtles (Chelonia mydas by measuring auditory evoked potential responses to tone pip stimuli. Green sea turtles detected acoustic stimuli in both media, responding to underwater stimuli between 50 and 1600 Hz and aerial stimuli between 50 and 800 Hz, with maximum sensitivity between 200 and 400 Hz underwater and 300 and 400 Hz in air. When underwater and aerial hearing sensitivities were compared in terms of pressure, green sea turtle aerial sound pressure thresholds were lower than underwater thresholds, however they detected a wider range of frequencies underwater. When thresholds were compared in terms of sound intensity, green sea turtle sound intensity level thresholds were 2-39 dB lower underwater particularly at frequencies below 400 Hz. Acoustic stimuli may provide important environmental cues for sea turtles. Further research is needed to determine how sea turtles behaviorally and physiologically respond to sounds in their environment.

  10. Audiogram of a formerly stranded long-finned pilot whale (Globicephala melas) measured using auditory evoked potentials.

    Science.gov (United States)

    Pacini, A F; Nachtigall, P E; Kloepper, L N; Linnenschmidt, M; Sogorb, A; Matias, S

    2010-09-15

    Long-finned pilot whales are highly social odontocetes found in temperate and subpolar regions. This species is particularly known for its interaction with fisheries as well as its mass strandings. Recent tagging work has provided some information about pilot whales in the wild but, even though they have been successfully kept in captivity, little is known about their sensory capabilities. This study investigates the hearing abilities of a rehabilitated 2 year old male long-finned pilot whale. A complete audiogram was collected using auditory evoked potential techniques that included measurements of nine frequencies from 4 to 100 kHz presented as sinusoidally amplitude-modulated tones. The results indicated that the region of best hearing was between 11.2 and 50 kHz and the subject had relatively poor high frequency hearing compared with other odontocete species. This study emphasizes the importance of collecting basic hearing measurements from new species, understanding diagnostic life histories as well as continuously increasing the sample size of audiometry measurements within and between odontocete species as animals become available.

  11. Cortical Auditory Evoked Potentials Reveal Changes in Audibility with Nonlinear Frequency Compression in Hearing Aids for Children: Clinical Implications.

    Science.gov (United States)

    Ching, Teresa Y C; Zhang, Vicky W; Hou, Sanna; Van Buynder, Patricia

    2016-02-01

    Hearing loss in children is detected soon after birth via newborn hearing screening. Procedures for early hearing assessment and hearing aid fitting are well established, but methods for evaluating the effectiveness of amplification for young children are limited. One promising approach to validating hearing aid fittings is to measure cortical auditory evoked potentials (CAEPs). This article provides first a brief overview of reports on the use of CAEPs for evaluation of hearing aids. Second, a study that measured CAEPs to evaluate nonlinear frequency compression (NLFC) in hearing aids for 27 children (between 6.1 and 16.8 years old) who have mild to severe hearing loss is reported. There was no significant difference in aided sensation level or the detection of CAEPs for /g/ between NLFC on and off conditions. The activation of NLFC was associated with a significant increase in aided sensation levels for /t/ and /s/. It also was associated with an increase in detection of CAEPs for /t/ and /s/. The findings support the use of CAEPs for checking audibility provided by hearing aids. Based on the current data, a clinical protocol for using CAEPs to validate audibility with amplification is presented.

  12. The Loudness Dependence of Auditory Evoked Potentials (LDAEP) in individuals at risk for developing bipolar disorders and schizophrenia.

    Science.gov (United States)

    Hagenmuller, Florence; Heekeren, Karsten; Meier, Magali; Theodoridou, Anastasia; Walitza, Susanne; Haker, Helene; Rössler, Wulf; Kawohl, Wolfram

    2016-02-01

    The Loudness Dependence of Auditory Evoked Potentials (LDAEP) is considered as an indicator of central serotonergic activity. Alteration of serotonergic neurotransmission was reported in bipolar disorders and schizophrenia. In line with previous reports on clinically manifest disorders, we expected a weaker LDAEP in subjects at risk for bipolar disorders and schizophrenia compared to healthy controls. We analyzed LDAEP of individuals at risk for developing bipolar disorders (n=27), with high-risk status (n=74) and ultra-high-risk status for schizophrenia (n=86) and healthy controls (n=47). The LDAEP did not differ between subjects at risk for schizophrenia or bipolar disorders and controls. Among subjects without medication (n=122), the at-risk-bipolar group showed a trend towards a weaker LDAEP than both the high-risk and the ultra-high-risk groups for schizophrenia. The LDAEP did not appear as a vulnerability marker for schizophrenia or bipolar disorders. This suggests that an altered LDAEP may not be measurable until the onset of clinically manifest disorder. However, the hypothesis that pathogenic mechanisms leading to bipolar disorders may differ from those leading to schizophrenia is supported. This is the first study investigating LDAEP in a population at risk for bipolar disorders. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  13. Vocal sequences suppress spiking in the bat auditory cortex while evoking concomitant steady-state local field potentials.

    Science.gov (United States)

    Hechavarría, Julio C; Beetz, M Jerome; Macias, Silvio; Kössl, Manfred

    2016-12-15

    The mechanisms by which the mammalian brain copes with information from natural vocalization streams remain poorly understood. This article shows that in highly vocal animals, such as the bat species Carollia perspicillata, the spike activity of auditory cortex neurons does not track the temporal information flow enclosed in fast time-varying vocalization streams emitted by conspecifics. For example, leading syllables of so-called distress sequences (produced by bats subjected to duress) suppress cortical spiking to lagging syllables. Local fields potentials (LFPs) recorded simultaneously to cortical spiking evoked by distress sequences carry multiplexed information, with response suppression occurring in low frequency LFPs (i.e. 2-15 Hz) and steady-state LFPs occurring at frequencies that match the rate of energy fluctuations in the incoming sound streams (i.e. >50 Hz). Such steady-state LFPs could reflect underlying synaptic activity that does not necessarily lead to cortical spiking in response to natural fast time-varying vocal sequences.

  14. Correlation analysis of the long latency auditory evoked potential N2 and cognitive P3 with the level of lead poisoning in children

    Directory of Open Access Journals (Sweden)

    Alvarenga, Kátia de Freitas

    2013-01-01

    Full Text Available Introduction: The effects of lead on children's health have been widely studied. Aim: To analyze the correlation between the long latency auditory evoked potential N2 and cognitive P3 with the level of lead poisoning in Brazilian children. Methods: This retrospective study evaluated 20 children ranging in age from 7 to 14 years at the time of audiological and electrophysiological evaluations. We performed periodic surveys of the lead concentration in the blood and basic audiological evaluations. Furthermore, we studied the auditory evoked potential long latency N2 and cognitive P3 by analyzing the absolute latency of the N2 and P3 potentials and the P3 amplitude recorded at Cz. At the time of audiological and electrophysiological evaluations, the average concentration of lead in the blood was less than 10 ug/dL. Results: In conventional audiologic evaluations, all children had hearing thresholds below 20 dBHL for the frequencies tested and normal tympanometry findings; the auditory evoked potential long latency N2 and cognitive P3 were present in 95% of children. No significant correlations were found between the blood lead concentration and latency (p = 0.821 or amplitude (p = 0.411 of the P3 potential. However, the latency of the N2 potential increased with the concentration of lead in the blood, with a significant correlation (p = 0.030. Conclusion: Among Brazilian children with low lead exposure, a significant correlation was found between blood lead levels and the average latency of the auditory evoked potential long latency N2; however, a significant correlation was not observed for the amplitude and latency of the cognitive potential P3.

  15. Auditory evoked potentials in patients with major depressive disorder measured by Emotiv system.

    Science.gov (United States)

    Wang, Dongcui; Mo, Fongming; Zhang, Yangde; Yang, Chao; Liu, Jun; Chen, Zhencheng; Zhao, Jinfeng

    2015-01-01

    In a previous study (unpublished), Emotiv headset was validated for capturing event-related potentials (ERPs) from normal subjects. In the present follow-up study, the signal quality of Emotiv headset was tested by the accuracy rate of discriminating Major Depressive Disorder (MDD) patients from the normal subjects. ERPs of 22 MDD patients and 15 normal subjects were induced by an auditory oddball task and the amplitude of N1, N2 and P3 of ERP components were specifically analyzed. The features of ERPs were statistically investigated. It is found that Emotiv headset is capable of discriminating the abnormal N1, N2 and P3 components in MDD patients. Relief-F algorithm was applied to all features for feature selection. The selected features were then input to a linear discriminant analysis (LDA) classifier with leave-one-out cross-validation to characterize the ERP features of MDD. 127 possible combinations out of the selected 7 ERP features were classified using LDA. The best classification accuracy was achieved to be 89.66%. These results suggest that MDD patients are identifiable from normal subjects by ERPs measured by Emotiv headset.

  16. Auditory evoked potentials to speech and nonspeech stimuli are associated with verbal skills in preschoolers

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    Soila Kuuluvainen

    2016-06-01

    Full Text Available Children’s obligatory auditory event-related potentials (ERPs to speech and nonspeech sounds have been shown to associate with reading performance in children at risk or with dyslexia and their controls. However, very little is known of the cognitive processes these responses reflect. To investigate this question, we recorded ERPs to semisynthetic syllables and their acoustically matched nonspeech counterparts in 63 typically developed preschoolers, and assessed their verbal skills with an extensive set of neurocognitive tests. P1 and N2 amplitudes were larger for nonspeech than speech stimuli, whereas the opposite was true for N4. Furthermore, left-lateralized P1s were associated with better phonological and prereading skills, and larger P1s to nonspeech than speech stimuli with poorer verbal reasoning performance. Moreover, left-lateralized N2s, and equal-sized N4s to both speech and nonspeech stimuli were associated with slower naming. In contrast, children with equal-sized N2 amplitudes at left and right scalp locations, and larger N4s for speech than nonspeech stimuli, performed fastest. We discuss the possibility that children’s ERPs reflect not only neural encoding of sounds, but also sound quality processing, memory-trace construction, and lexical access. The results also corroborate previous findings that speech and nonspeech sounds are processed by at least partially distinct neural substrates.

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

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    Jian-ning ZHANG

    2012-08-01

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

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

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    Musacchia, Gabriella; Strait, Dana; Kraus, Nina

    2008-01-01

    Musicians have a variety of perceptual and cortical specializations compared to non-musicians. Recent studies have shown that potentials evoked from primarily brainstem structures are enhanced in musicians, compared to non-musicians. Specifically, musicians have more robust representations of pitch periodicity and faster neural timing to sound onset when listening to sounds or both listening to and viewing a speaker. However, it is not known whether musician-related enhancements at the subcortical level are correlated with specializations in the cortex. Does musical training shape the auditory system in a coordinated manner or in disparate ways at cortical and subcortical levels? To answer this question, we recorded simultaneous brainstem and cortical evoked responses in musician and non-musician subjects. Brainstem response periodicity was related to early cortical response timing across all subjects, and this relationship was stronger in musicians. Peaks of the brainstem response evoked by sound onset and timbre cues were also related to cortical timing. Neurophysiological measures at both levels correlated with musical skill scores across all subjects. In addition, brainstem and cortical measures correlated with the age musicians began their training and the years of musical practice. Taken together, these data imply that neural representations of pitch, timing and timbre cues and cortical response timing are shaped in a coordinated manner, and indicate corticofugal modulation of subcortical afferent circuitry. PMID:18562137

  19. Acute Stress Alters Auditory Selective Attention in Humans Independent of HPA: A Study of Evoked Potentials

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    Elling, Ludger; Steinberg, Christian; Bröckelmann, Ann-Kathrin; Dobel, Christan; Bölte, Jens; Junghofer, Markus

    2011-01-01

    Background Acute stress is a stereotypical, but multimodal response to a present or imminent challenge overcharging an organism. Among the different branches of this multimodal response, the consequences of glucocorticoid secretion have been extensively investigated, mostly in connection with long-term memory (LTM). However, stress responses comprise other endocrine signaling and altered neuronal activity wholly independent of pituitary regulation. To date, knowledge of the impact of such “paracorticoidal” stress responses on higher cognitive functions is scarce. We investigated the impact of an ecological stressor on the ability to direct selective attention using event-related potentials in humans. Based on research in rodents, we assumed that a stress-induced imbalance of catecholaminergic transmission would impair this ability. Methodology/Principal Findings The stressor consisted of a single cold pressor test. Auditory negative difference (Nd) and mismatch negativity (MMN) were recorded in a tonal dichotic listening task. A time series of such tasks confirmed an increased distractibility occuring 4–7 minutes after onset of the stressor as reflected by an attenuated Nd. Salivary cortisol began to rise 8–11 minutes after onset when no further modulations in the event-related potentials (ERP) occurred, thus precluding a causal relationship. This effect may be attributed to a stress-induced activation of mesofrontal dopaminergic projections. It may also be attributed to an activation of noradrenergic projections. Known characteristics of the modulation of ERP by different stress-related ligands were used for further disambiguation of causality. The conjuncture of an attenuated Nd and an increased MMN might be interpreted as indicating a dopaminergic influence. The selective effect on the late portion of the Nd provides another tentative clue for this. Conclusions/Significance Prior studies have deliberately tracked the adrenocortical influence on cognition

  20. Dopamine modulates attentional control of auditory perception: DARPP-32 (PPP1R1B) genotype effects on behavior and cortical evoked potentials.

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    Li, Shu-Chen; Passow, Susanne; Nietfeld, Wilfried; Schröder, Julia; Bertram, Lars; Heekeren, Hauke R; Lindenberger, Ulman

    2013-07-01

    Using a specific variant of the dichotic listening paradigm, we studied the influence of dopamine on attentional modulation of auditory perception by assessing effects of allelic variation of a single-nucleotide polymorphism (SNP) rs907094 in the DARPP-32 gene (dopamine and adenosine 3', 5'-monophosphate-regulated phosphoprotein 32 kilodations; also known as PPP1R1B) on behavior and cortical evoked potentials. A frequent DARPP-32 haplotype that includes the A allele of this SNP is associated with higher mRNA expression of DARPP-32 protein isoforms, striatal dopamine receptor function, and frontal-striatal connectivity. As we hypothesized, behaviorally the A homozygotes were more flexible in selectively attending to auditory inputs than any G carriers. Moreover, this genotype also affected auditory evoked cortical potentials that reflect early sensory and late attentional processes. Specifically, analyses of event-related potentials (ERPs) revealed that amplitudes of an early component of sensory selection (N1) and a late component (N450) reflecting attentional deployment for conflict resolution were larger in A homozygotes than in any G carriers. Taken together, our data lend support for dopamine's role in modulating auditory attention both during the early sensory selection and late conflict resolution stages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Acoustic trauma slows AMPA receptor-mediated EPSCs in the auditory brainstem, reducing GluA4 subunit expression as a mechanism to rescue binaural function.

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    Pilati, Nadia; Linley, Deborah M; Selvaskandan, Haresh; Uchitel, Osvaldo; Hennig, Matthias H; Kopp-Scheinpflug, Cornelia; Forsythe, Ian D

    2016-07-01

    Lateral superior olive (LSO) principal neurons receive AMPA receptor (AMPAR) - and NMDA receptor (NMDAR)-mediated EPSCs and glycinergic IPSCs. Both EPSCs and IPSCs have slow kinetics in prehearing animals, which during developmental maturation accelerate to sub-millisecond decay time-constants. This correlates with a change in glutamate and glycine receptor subunit composition quantified via mRNA levels. The NMDAR-EPSCs accelerate over development to achieve decay time-constants of 2.5 ms. This is the fastest NMDAR-mediated EPSC reported. Acoustic trauma (AT, loud sounds) slow AMPAR-EPSC decay times, increasing GluA1 and decreasing GluA4 mRNA. Modelling of interaural intensity difference suggests that the increased EPSC duration after AT shifts interaural level difference to the right and compensates for hearing loss. Two months after AT the EPSC decay times recovered to control values. Synaptic transmission in the LSO matures by postnatal day 20, with EPSCs and IPSCs having fast kinetics. AT changes the AMPAR subunits expressed and slows the EPSC time-course at synapses in the central auditory system. Damaging levels of sound (acoustic trauma, AT) diminish peripheral synapses, but what is the impact on the central auditory pathway? Developmental maturation of synaptic function and hearing were characterized in the mouse lateral superior olive (LSO) from postnatal day 7 (P7) to P96 using voltage-clamp and auditory brainstem responses. IPSCs and EPSCs show rapid acceleration during development, so that decay kinetics converge to similar sub-millisecond time-constants (τ, 0.87 ± 0.11 and 0.77 ± 0.08 ms, respectively) in adult mice. This correlated with LSO mRNA levels for glycinergic and glutamatergic ionotropic receptor subunits, confirming a switch from Glyα2 to Glyα1 for IPSCs and increased expression of GluA3 and GluA4 subunits for EPSCs. The NMDA receptor (NMDAR)-EPSC decay τ accelerated from >40 ms in prehearing animals to 2.6 ± 0.4 ms in

  2. A prospective, randomized, double-blind trial of intranasal dexmedetomidine and oral chloral hydrate for sedated auditory brainstem response (ABR) testing.

    Science.gov (United States)

    Reynolds, Jason; Rogers, Amber; Medellin, Eduardo; Guzman, Jonathan A; Watcha, Mehernoor F

    2016-03-01

    Dexmedetomidine is increasingly used by various routes for pediatric sedation. However, there are few randomized controlled trials comparing the efficacy of dexmedetomidine to other commonly used sedatives. To compare the efficacy of sedation with intranasal dexmedetomidine to oral chloral hydrate for auditory brainstem response (ABR) testing. In this double-blind, double-dummy study, children undergoing ABR testing were randomized to receive intranasal dexmedetomidine 3 mcg · kg(-1) plus oral placebo (Group IN DEX) or oral chloral hydrate 50 mg · kg(-1) plus intranasal saline placebo (Group CH). We recorded demographic data, times from sedative administration to start and completion of testing, quality of sedation, occurrence of predefined adverse events, discharge times, and return to baseline activity on the day of testing. Testing completion rates with a single dose of medication were higher in the IN DEX group (89% vs 66% for CH, odds ratio with 95% confidence intervals 4.04 [1.3-12.6], P = 0.018). The median [95% CI)] time to successful testing start was shorter (25 [20-29] min vs 30 [20-49] min for IN DEX and CH, respectively, log rank test P = 0.02) and the proportion of children whose parents reported a return to baseline activity on the day of testing was greater for the IN DEX than the CH group (89% vs 64%, OR [95% CI] 4.71 [1.34-16.6], P = 0.02). There were no major adverse events in either group and no significant differences in the incidence of minor events. Intranasal dexmedetomidine is an effective alternative to oral chloral hydrate sedation for ABR testing, with the advantages of a higher incidence of testing completion with a single dose, shorter time to desired sedation level, and with significantly more patients reported to return to baseline activity on the same day. © 2016 John Wiley & Sons Ltd.

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

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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.

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

    Science.gov (United States)

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

    2015-01-01

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

  5. Sensitivity of cortical auditory evoked potential detection for hearing-impaired infants in response to short speech sounds

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    Bram Van Dun

    2012-01-01

    Full Text Available

    Background: Cortical auditory evoked potentials (CAEPs are an emerging tool for hearing aid fitting evaluation in young children who cannot provide reliable behavioral feedback. It is therefore useful to determine the relationship between the sensation level of speech sounds and the detection sensitivity of CAEPs.

    Design and methods: Twenty-five sensorineurally hearing impaired infants with an age range of 8 to 30 months were tested once, 18 aided and 7 unaided. First, behavioral thresholds of speech stimuli /m/, /g/, and /t/ were determined using visual reinforcement orientation audiometry (VROA. Afterwards, the same speech stimuli were presented at 55, 65, and 75 dB SPL, and CAEP recordings were made. An automatic statistical detection paradigm was used for CAEP detection.

    Results: For sensation levels above 0, 10, and 20 dB respectively, detection sensitivities were equal to 72 ± 10, 75 ± 10, and 78 ± 12%. In 79% of the cases, automatic detection p-values became smaller when the sensation level was increased by 10 dB.

    Conclusions: The results of this study suggest that the presence or absence of CAEPs can provide some indication of the audibility of a speech sound for infants with sensorineural hearing loss. The detection of a CAEP provides confidence, to a degree commensurate with the detection probability, that the infant is detecting that sound at the level presented. When testing infants where the audibility of speech sounds has not been established behaviorally, the lack of a cortical response indicates the possibility, but by no means a certainty, that the sensation level is 10 dB or less.

  6. Sensitivity of cortical auditory evoked potential detection for hearing-impaired infants in response to short speech sounds

    Directory of Open Access Journals (Sweden)

    Bram Van Dun

    2012-08-01

    Full Text Available Cortical auditory evoked potentials (CAEPs are an emerging tool for hearing aid fitting evaluation in young children who cannot provide reliable behavioral feedback. It is therefore useful to determine the relationship between the sensation level of speech sounds and the detection sensitivity of CAEPs, which is the ratio between the number of detections and the sum of detections and non-detections. Twenty-five sensorineurally hearing impaired infants with an age range of 8 to 30 months were tested once, 18 aided and 7 unaided. First, behavioral thresholds of speech stimuli /m/, /g/, and /t/ were determined using visual reinforcement orientation audiometry. Afterwards, the same speech stimuli were presented at 55, 65, and 75 dB sound pressure level, and CAEPs were recorded. An automatic statistical detection paradigm was used for CAEP detection. For sensation levels above 0, 10, and 20 dB respectively, detection sensitivities were equal to 72±10, 75±10, and 78±12%. In 79% of the cases, automatic detection P-values became smaller when the sensation level was increased by 10 dB. The results of this study suggest that the presence or absence of CAEPs can provide some indication of the audibility of a speech sound for infants with sensorineural hearing loss. The detection of a CAEP might provide confidence, to a degree commensurate with the detection probability, that the infant is detecting that sound at the level presented. When testing infants where the audibility of speech sounds has not been established behaviorally, the lack of a cortical response indicates the possibility, but by no means a certainty, that the sensation level is 10 dB or less.

  7. Otoacoustic emissions, auditory evoked potentials and self-reported gender in people affected by disorders of sex development (DSD).

    Science.gov (United States)

    Wisniewski, Amy B; Espinoza-Varas, Blas; Aston, Christopher E; Edmundson, Shelagh; Champlin, Craig A; Pasanen, Edward G; McFadden, Dennis

    2014-08-01

    Both otoacoustic emissions (OAEs) and auditory evoked potentials (AEPs) are sexually dimorphic, and both are believed to be influenced by prenatal androgen exposure. OAEs and AEPs were collected from people affected by 1 of 3 categories of disorders of sex development (DSD) - (1) women with complete androgen insensitivity syndrome (CAIS); (2) women with congenital adrenal hyperplasia (CAH); and (3) individuals with 46,XY DSD including prenatal androgen exposure who developed a male gender despite initial rearing as females (men with DSD). Gender identity (GI) and role (GR) were measured both retrospectively and at the time of study participation, using standardized questionnaires. The main objective of this study was to determine if patterns of OAEs and AEPs correlate with gender in people affected by DSD and in controls. A second objective was to assess if OAE and AEP patterns differed according to degrees of prenatal androgen exposure across groups. Control males, men with DSD, and women with CAH produced fewer spontaneous OAEs (SOAEs) - the male-typical pattern - than control females and women with CAIS. Additionally, the number of SOAEs produced correlated with gender development across all groups tested. Although some sex differences in AEPs were observed between control males and females, AEP measures did not correlate with gender development, nor did they vary according to degrees of prenatal androgen exposure, among people with DSD. Thus, OAEs, but not AEPs, may prove useful as bioassays for assessing early brain exposure to androgens and predicting gender development in people with DSD. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. The effects of polarity of click stimulation on auditory brainstem responses (ABR in patients with cochlear and retro-cochlear disorders in Amiralam and Resalat Hospitals 1995-97

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    Soltani AH

    2002-08-01

    Full Text Available Background: Auditory brainstem response (A.B.R is one of the most important electrophysiological tests in evaluating of auditory system, especially for diagnosing of auditory nerve and brainstem disorders. It is a non-invasive test and has reliability and validity characteristic. There is no contra-indication for this test. One of the most important of stimulation parameters of A.B.R is click polarity (rarefaction, condensation and alternative. Some of the investigators believed that different polarities have no effects on A.B.R are affected by different polarities. Materials and Methods: In this study, the results of ABR of 148 patients (296 ears were compared with three different polarities of rarefaction, condensation and alternative half click stimuli. The cases were categorized in three groups of normal (60 cases, cochlear (62 cases and retro-cochlear (17 cases. This classification were done according to the hearing level in pure tone audiometry results in three frequencies of 1000, 2000, 4000 Hz and to the site of the their disorders. The mean absolute latencies of waves I, III and V were obtained for each polarity. Inter-peak latency (I.P.L of wave also measured in three groups (normal, cochlear and retro-cochlear. Results: The results were showed a significant difference between absolute latency of wave I among different polarities on three above mentioned groups (P0.05. Conclusion: It was concluded that rarefaction polarity has better and more stable results of ABR tests.

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

    Science.gov (United States)

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

    2014-07-01

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

  10. A case of generalized auditory agnosia with unilateral subcortical brain lesion.

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

    2012-12-01

    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.

  11. Relação entre potenciais evocados auditivos de média latência e distúrbio de processamento auditivo: estudo de casos Relationship between auditory evoked potentials and middle latency auditory processing disorder: cases study

    Directory of Open Access Journals (Sweden)

    Ana Carla Leite Romero

    2013-04-01

    Full Text Available O Potencial Evocado Auditivo de Média Latência é um teste objetivo promissor na audiologia na pesquisa neuro-diagnóstica das disfunções do sistema auditivo. Tem como vantagens a precisão e objetividade na avaliação e por isso é útil em crianças. O presente estudo teve como objetivo analisar os potenciais evocados auditivos de média latência em dois pacientes com distúrbio de processamento auditivo e relacionar as medidas objetivas e comportamentais. Para tanto foi realizado estudo de caso de dois pacientes (P1= feminino, 12 anos; P2= masculino, 17 anos, ambos com ausência de alterações sensoriais, distúrbios neurológicos, neuropsiquiátricos. Ambos foram submetidos à anamnese, inspeção do meato acústico externo, avaliação audiológica e avaliação do exame de potencial evocado auditivo de média latência. Houve associação significante entre os resultados dos exames comportamentais e objetivos. Na anamnese, houve queixas referentes à dificuldade de escuta em ambiente ruidoso, localização sonora, desatenção, além de trocas fonológicas na escrita e na fala. Foram observadas alterações no processo de decodificação auditiva à direita em ambos os casos na avaliação comportamental do processamento auditivo e no exame de potencial evocado auditivo de média latência a resposta da via contralateral direita foi deficitária, confirmando as dificuldades dos pacientes estudados na atribuição de significado às informações acústicas em condição de competição sonora à direita nos dois casos. Para os casos estudados comprovou-se à associação entre os resultados, porém há necessidade de novos estudos com maior amostra para confirmação dos dados.The Auditory Evoked Middle Latency Response is one of the most promising objective tests in audiology and in revealing brain dysfunction and neuro-audiologic findings. The main advantages of its clinical use are precision and objectivity in evaluating children

  12. Relação entre potenciais evocados auditivos de média latência e distúrbio de processamento auditivo: estudo de casos Relationship between auditory evoked potentials and middle latency auditory processing disorder: cases study

    Directory of Open Access Journals (Sweden)

    Ana Carla Leite Romero

    2013-01-01

    Full Text Available O Potencial Evocado Auditivo de Média Latência é um teste objetivo promissor na audiologia na pesquisa neuro-diagnóstica das disfunções do sistema auditivo. Tem como vantagens a precisão e objetividade na avaliação e por isso é útil em crianças. O presente estudo teve como objetivo analisar os potenciais evocados auditivos de média latência em dois pacientes com distúrbio de processamento auditivo e relacionar as medidas objetivas e comportamentais. Para tanto foi realizado estudo de caso de dois pacientes (P1= feminino, 12 anos; P2= masculino, 17 anos, ambos com ausência de alterações sensoriais, distúrbios neurológicos, neuropsiquiátricos. Ambos foram submetidos à anamnese, inspeção do meato acústico externo, avaliação audiológica e avaliação do exame de potencial evocado auditivo de média latência. Houve associação significante entre os resultados dos exames comportamentais e objetivos. Na anamnese, houve queixas referentes à dificuldade de escuta em ambiente ruidoso, localização sonora, desatenção, além de trocas fonológicas na escrita e na fala. Foram observadas alterações no processo de decodificação auditiva à direita em ambos os casos na avaliação comportamental do processamento auditivo e no exame de potencial evocado auditivo de média latência a resposta da via contralateral direita foi deficitária, confirmando as dificuldades dos pacientes estudados na atribuição de significado às informações acústicas em condição de competição sonora à direita nos dois casos. Para os casos estudados comprovou-se à associação entre os resultados, porém há necessidade de novos estudos com maior amostra para confirmação dos dados.The Auditory Evoked Middle Latency Response is one of the most promising objective tests in audiology and in revealing brain dysfunction and neuro-audiologic findings. The main advantages of its clinical use are precision and objectivity in evaluating children

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

    Science.gov (United States)

    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.

  14. Sedation and anesthesia of hatchling leatherback sea turtles (Dermochelys coriacea) for auditory evoked potential measurement in air and in water.

    Science.gov (United States)

    Harms, Craig A; Piniak, Wendy E D; Eckert, Scott A; Stringer, Elizabeth M

    2014-03-01

    Sedation or anesthesia of hatchling leatherback sea turtles was employed to acquire auditory evoked potential (AEP) measurements in air and in water to assess their hearing sensitivity in relation to potential consequences from anthropogenic noise. To reduce artifacts in AEP collection caused by muscle movement, hatchlings were sedated with midazolam 2 or 3 mg/kg i.v. for in-air (n = 7) or in-water (n = 11) AEP measurements; hatchlings (n = 5) were anesthetized with ketamine 6 mg/kg and dexmedetomidine 30 microg/kg i.v. reversed with atipamezole 300 microg/kg, half i.m. and half i.v. for in-air AEP measurements. Midazolam-sedated turtles were also physically restrained with a light elastic wrap. For in-water AEP measurements, sedated turtles were brought to the surface every 45-60 sec, or whenever they showed intention signs for breathing, and not submerged again until they took a breath. Postprocedure temperature-corrected venous blood pH, pCO2, pO2, and HCO3- did not differ among groups, although for the midazolam-sedated in-water group, pCO2 trended lower, and in the ketamine-dexmedetomidine anesthetized group there was one turtle considered clinically acidotic (temperature-corrected pH = 7.117). Venous blood lactate was greater for hatchlings recently emerged from the nest than for turtles sedated with midazolam in air, with the other two groups falling intermediate between, but not differing significantly from the high and low lactate groups. Disruptive movements were less frequent with anesthesia than with sedation in the in-air group. Both sedation with midazolam and anesthesia with ketamine-dexmedetomidine were successful for allowing AEP measurements in hatchling leatherback sea turtles. Sedation allowed the turtle to protect its airway voluntarily while limiting flipper movement. Midazolam or ketamine-dexmedetomidine (and reversal with atipamezole) would be useful for other procedures requiring minor or major restraint in leatherback sea turtle hatchlings

  15. Electrodiagnostic evaluation of auditory function in the dog.

    Science.gov (United States)

    Scheifele, Peter M; Clark, John Greer

    2012-11-01

    Given the high incidence of deafness within several breeds of dogs, accurate hearing screening and assessment is essential. In addition to brainstem auditory evoked response (BAER) testing, 2 other electrophysiologic tests are now being examined as audiologic tools for use in veterinary medicine: otoacoustic emissions and the auditory steady state response (ASSR). To improve BAER testing of animals and ensure an accurate interpretation of test findings from one test site to another, the establishment of and adherence to clear protocols is essential. The ASSR holds promise as an objective test for rapid testing of multiple frequencies in both ears simultaneously. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Influência dos contrastes de fala nos potenciais evocados auditivos corticais The influence of speech stimuli contrast in cortical auditory evoked potentials

    Directory of Open Access Journals (Sweden)

    Kátia de Freitas Alvarenga

    2013-06-01

    Full Text Available Estudos voltados aos potenciais evocados auditivos com estímulos de fala em indivíduos ouvintes são importantes para compreender como a complexidade do estímulo influencia nas características do potencial cognitivo auditivo gerado. OBJETIVO: Caracterizar o potencial evocado auditivo cortical e o potencial cognitivo auditivo P3 com estímulos de contrastes vocálico e consonantal em indivíduos com audição normal. MÉTODO: Participaram deste estudo 31 indivíduos sem alterações auditivas, neurológicas e de linguagem na faixa etária de 7 a 30 anos. Os potenciais evocados auditivos corticais e cognitivo auditivo P3 foram registrados nos canais ativos Fz e Cz utilizando-se os contrastes de fala consonantal (/ba/-/da/ e vocálico (/i/-/a/. Desenho: Estudo de coorte, transversal e prospectivo. RESULTADOS: Houve diferença entre o contraste de fala utilizado e as latências dos componentes N2 (p = 0,00 e P3 (p = 0,00, assim como entre o canal ativo considerado (Fz/Cz e os valores de latência e amplitude de P3. Estas diferenças não ocorreram para os componentes exógenos N1 e P2. CONCLUSÃO: O contraste do estímulo de fala, vocálico ou consonantal, deve ser considerado na análise do potencial evocado cortical, componente N2, e do potencial cognitivo auditivo P3.Studies about cortical auditory evoked potentials using the speech stimuli in normal hearing individuals are important for understanding how the complexity of the stimulus influences the characteristics of the cortical potential generated. OBJECTIVE: To characterize the cortical auditory evoked potential and the P3 auditory cognitive potential with the vocalic and consonantal contrast stimuli in normally hearing individuals. METHOD: 31 individuals with no risk for hearing, neurologic and language alterations, in the age range between 7 and 30 years, participated in this study. The cortical auditory evoked potentials and the P3 auditory cognitive one were recorded in the Fz and Cz

  17. Hyperekplexia and trismus due to brainstem encephalopathy

    Science.gov (United States)

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

    1998-01-01

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

 PMID:9667574

  18. The value of brainstem evoked potential in clinical decision of a patient with hypoxic-ischemic encephalopathy O valor do potencial evocado auditivo em decisão clínica em paciente com síndrome hipóxico-isquêmica

    Directory of Open Access Journals (Sweden)

    Anna Lecticia R. Pinto

    2007-09-01

    Full Text Available Establishing a prognosis for hypoxic-ischemic encephalopathy during the neonatal period is extremely difficult, as the neuroplasticity of the developing brain makes it almost impossible to measure the affected area. This case report describes a newborn with severe perinatal asphyxia and neonatal neurological syndrome including absent suck reflex. Normal brainstem auditory evoked potential led the diagnosis towards a transitory dysfunction of deglutition, and the subject received daily stimulation in the hospital environment. Suck developed satisfactorily by day of life 30 and the patient was released without having to be tube fed. Neurophysiologic tests can be of value in the clinical decisions and analysis of functional prognosis of patients with hypoxic-ischemic encephalopathy.Estabelecer o prognóstico da encefalopatia hipóxico-isquêmica durante o período neonatal é extremamente difícil, devido à neuroplasticidade do cérebro em desenvolvimento que impede a medida exata das áreas afetadas. Este relato descreve um recém-nascido a termo com grave asfixia perinatal e síndrome neurológica pós-natal, incluindo ausência do reflexo de sucção. O potencial evocado auditivo do tronco cerebral foi normal, sugerindo o diagnóstico de disfunção transitória da deglutição. Após estimulação diária no hospital a sucção foi obtida satisfatoriamente, e o paciente recebeu alta sem necessidade de alimentação enteral. Os testes neurofisiológicos podem ser de grande valor em decisões clínicas e análise funcional prognóstica de pacientes com encefalopatia hipóxico-isquêmica.

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

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    Ji Youn Kim

    2010-04-01

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

  20. The human auditory system: a timeline of development.

    Science.gov (United States)

    Moore, Jean K; Linthicum, Fred H

    2007-09-01

    This review traces the structural maturation of the human auditory system, and compares the timeline of anatomical development with cotemporaneous physiological and behavioral events. During the embryonic period, there is formation of basic structure at all levels of the system, i.e. the inner ear, the brainstem pathway, and the cortex. The second trimester is a time of rapid growth and development, and by the end of this period, the cochlea has acquired a very adult-like configuration. During the perinatal period, the brainstem reaches a mature state, and brainstem activity is reflected in behavioral responses to sound, including phonetic discrimination, and in evoked brainstem and early middle latency responses. The perinatal period is also the time of peak development of brainstem input to the cortex through the marginal layer, and of the long latency cortical potentials, the N(2) and mismatch negativity. In early childhood, from the sixth post-natal month to age five, there is progressive maturation of the thalamic projections to the cortex and of the longer latency Pa and P(1) evoked potentials. Later childhood, from six to twelve years, is the time of maturation of the superficial cortical layers and their intracortical connections, accompanied by appearance of the N(1) potential and improved linguistic discriminative abilities. Some consideration is given to the potential negative effects of deafness-induced sound deprivation during the perinatal period and childhood.

  1. A case of bulbar type cerebral palsy: representative symptoms of dorsal brainstem syndrome.

    Science.gov (United States)

    Hiyane, Masato; Saito, Yoshiaki; Saito, Takashi; Komaki, Hirofumi; Nakagawa, Eiji; Sugai, Kenji; Sasaki, Masayuki; Sato, Noriko; Yamamoto, Toshiyuki; Imai, Yoko

    2012-10-01

    In this study, we present the case of a 2-year-old boy who exhibited facial and bulbar paralysis since birth, severe dysphagia, signs of oculomotor disturbance, jaw jerks, pyramidal signs on both toes, intellectual disability, and severe gastroesophageal reflux. His blink reflex and auditory/somatosensory evoked potentials suggested abnormalities in the lower brainstem, and magnetic resonance imaging showed a T2 hyperintense area in the pontine tegmentum. These findings combined with the patient's symptoms suggested "dorsal brainstem syndrome" and indicated a possibility of prenatal asphyxia in this patient. Nosologic issues regarding this subgroup of cerebral palsy are discussed here. Copyright © 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  2. Auditory Responses to Electric and Infrared Neural Stimulation of the Rat Cochlear Nucleus

    Science.gov (United States)

    Verma, Rohit; Guex, Amelie A.; Hancock, Kenneth E.; Durakovic, Nedim; McKay, Colette M.; Slama, Michaël C. C.; Brown, M. Christian; Lee, Daniel J.

    2014-01-01

    In an effort to improve the auditory brainstem implant, a prosthesis in which user outcomes are modest, we applied electric and infrared neural stimulation (INS) to the cochlear nucleus in a rat animal model. Electric stimulation evoked regions of neural activation in the inferior colliculus and short-latency, multipeaked auditory brainstem responses (ABRs). Pulsed INS, delivered to the surface of the cochlear nucleus via an optical fiber, evoked broad neural activation in the inferior colliculus. Strongest responses were recorded when the fiber was placed at lateral positions on the cochlear nucleus, close to the temporal bone. INS-evoked ABRs were multipeaked but longer in latency than those for electric stimulation; they resembled the responses to acoustic stimulation. After deafening, responses to electric stimulation persisted, whereas those to INS disappeared, consistent with a reported “optophonic” effect, a laser-induced acoustic artifact. Thus, for deaf individuals who use the auditory brainstem implant, INS alone did not appear promising as a new approach. PMID:24508368

  3. Auditory responses to electric and infrared neural stimulation of the rat cochlear nucleus.

    Science.gov (United States)

    Verma, Rohit U; Guex, Amélie A; Hancock, Kenneth E; Durakovic, Nedim; McKay, Colette M; Slama, Michaël C C; Brown, M Christian; Lee, Daniel J

    2014-04-01

    In an effort to improve the auditory brainstem implant, a prosthesis in which user outcomes are modest, we applied electric and infrared neural stimulation (INS) to the cochlear nucleus in a rat animal model. Electric stimulation evoked regions of neural activation in the inferior colliculus and short-latency, multipeaked auditory brainstem responses (ABRs). Pulsed INS, delivered to the surface of the cochlear nucleus via an optical fiber, evoked broad neural activation in the inferior colliculus. Strongest responses were recorded when the fiber was placed at lateral positions on the cochlear nucleus, close to the temporal bone. INS-evoked ABRs were multipeaked but longer in latency than those for electric stimulation; they resembled the responses to acoustic stimulation. After deafening, responses to electric stimulation persisted, whereas those to INS disappeared, consistent with a reported "optophonic" effect, a laser-induced acoustic artifact. Thus, for deaf individuals who use the auditory brainstem implant, INS alone did not appear promising as a new approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Autoregressive modeling with exogenous input of middle-latency auditory-evoked potentials to measure rapid changes in depth of anesthesia

    DEFF Research Database (Denmark)

    Jensen, E W; Lindholm, P; Henneberg, S W

    1996-01-01

    Obtaining an adequate depth of anesthesia is a continuous challenge to the anesthetist. With the introduction of muscle-relaxing agents the traditional signs of awareness are often obscured, or difficult to interpret. These signs include blood pressure, heart rate, pupil size, etc. However......, these factors do not describe the depth of anesthesia (DA) in a cerebral activity sense. Hence, a better measure of the DA is required. It has been suggested that Auditory-Evoked Potentials (AEP) can provide additional information about the DA. The general method of extracting AEP is by use of a Moving Time...... Average (MTA). However, the MTA is time consuming because a large number of repetitions is needed to produce an estimate of the AEP. Hence, changes occurring over a small number of sweeps will not be detected by the MTA average. We describe a system-identification method, an autoregressive model...

  5. Auditory processing in children and adolescents in situations of risk and vulnerability.

    Science.gov (United States)

    Murphy, Cristina Ferraz Borges; Pontes, Fernanda; Stivanin, Luciene; Picoli, Erica; Schochat, Eliane

    2012-01-01

    Children and adolescents who live in situations of social vulnerability present a series of health problems. Nonetheless, affirmations that sensory and cognitive abnormalities are present are a matter of controversy. The aim of this study was to investigate aspects to auditory processing, through applying the brainstem auditory evoked potential (BAEP) and behavioral auditory processing tests to children living on the streets, and comparison with a control group. Cross-sectional study in the Laboratory of Auditory Processing, School of Medicine, Universidade de São Paulo. The auditory processing tests were applied to a group of 27 individuals, subdivided into 11 children (7 to 10 years old) and 16 adolescents (11 to 16 years old), of both sexes, in situations of social vulnerability, compared with an age-matched control group of 10 children and 11 adolescents without complaints. The BAEP test was also applied to investigate the integrity of the auditory pathway. For both children and adolescents, there were significant differences between the study and control groups in most of the tests applied, with significantly worse performance in the study group, except in the pediatric speech intelligibility test. Only one child had an abnormal result in the BAEP test. The results showed that the study group (children and adolescents) presented poor performance in the behavioral auditory processing tests, despite their unaltered auditory brainstem pathways, as shown by their normal results in the BAEP test.

  6. Auditory processing in children and adolescents in situations of risk and vulnerability

    Directory of Open Access Journals (Sweden)

    Cristina Ferraz Borges Murphy

    Full Text Available CONTEXT AND OBJECTIVE: Children and adolescents who live in situations of social vulnerability present a series of health problems. Nonetheless, affirmations that sensory and cognitive abnormalities are present are a matter of controversy. The aim of this study was to investigate aspects to auditory processing, through applying the brainstem auditory evoked potential (BAEP and behavioral auditory processing tests to children living on the streets, and comparison with a control group. DESIGN AND SETTING: Cross-sectional study in the Laboratory of Auditory Processing, School of Medicine, Universidade de São Paulo. METHODS: The auditory processing tests were applied to a group of 27 individuals, subdivided into 11 children (7 to 10 years old and 16 adolescents (11 to 16 years old, of both sexes, in situations of social vulnerability, compared with an age-matched control group of 10 children and 11 adolescents without complaints. The BAEP test was also applied to investigate the integrity of the auditory pathway. RESULTS: For both children and adolescents, there were significant differences between the study and control groups in most of the tests applied, with significantly worse performance in the study group, except in the pediatric speech intelligibility test. Only one child had an abnormal result in the BAEP test. CONCLUSIONS: The results showed that the study group (children and adolescents presented poor performance in the behavioral auditory processing tests, despite their unaltered auditory brainstem pathways, as shown by their normal results in the BAEP test.

  7. A Pilot Study on Cortical Auditory Evoked Potentials in Children: Aided CAEPs Reflect Improved High-Frequency Audibility with Frequency Compression Hearing Aid Technology.

    Science.gov (United States)

    Glista, Danielle; Easwar, Vijayalakshmi; Purcell, David W; Scollie, Susan

    2012-01-01

    Background. This study investigated whether cortical auditory evoked potentials (CAEPs) could reliably be recorded and interpreted using clinical testing equipment, to assess the effects of hearing aid technology on the CAEP. Methods. Fifteen normal hearing (NH) and five hearing impaired (HI) children were included in the study. NH children were tested unaided; HI children were tested while wearing hearing aids. CAEPs were evoked with tone bursts presented at a suprathreshold level. Presence/absence of CAEPs was established based on agreement between two independent raters. Results. Present waveforms were interpreted for most NH listeners and all HI listeners, when stimuli were measured to be at an audible level. The younger NH children were found to have significantly different waveform morphology, compared to the older children, with grand averaged waveforms differing in the later part of the time window (the N2 response). Results suggest that in some children, frequency compression hearing aid processing improved audibility of specific frequencies, leading to increased rates of detectable cortical responses in HI children. Conclusions. These findings provide support for the use of CAEPs in measuring hearing aid benefit. Further research is needed to validate aided results across a larger group of HI participants and with speech-based stimuli.

  8. Neuroimaging with near-infrared spectroscopy demonstrates speech-evoked activity in the auditory cortex of deaf children following cochlear implantation.

    Science.gov (United States)

    Sevy, Alexander B G; Bortfeld, Heather; Huppert, Theodore J; Beauchamp, Michael S; Tonini, Ross E; Oghalai, John S

    2010-12-01

    Cochlear implants (CI) are commonly used to treat deafness in young children. While many factors influence the ability of a deaf child who is hearing through a CI to develop speech and language skills, an important factor is that the CI has to stimulate the auditory cortex. Obtaining behavioral measurements from young children with CIs can often be unreliable. While a variety of noninvasive techniques can be used for detecting cortical activity in response to auditory stimuli, many have critical limitations when applied to the pediatric CI population. We tested the ability of near-infrared spectroscopy (NIRS) to detect cortical responses to speech stimuli in pediatric CI users. Neuronal activity leads to changes in blood oxy- and deoxy-hemoglobin concentrations that can be detected by measuring the transmission of near-infrared light through the tissue. To verify the efficacy of NIRS, we first compared auditory cortex responses measured with NIRS and fMRI in normal-hearing adults. We then examined four different participant cohorts with NIRS alone. Speech-evoked cortical activity was observed in 100% of normal-hearing adults (11 of 11), 82% of normal-hearing children (9 of 11), 78% of deaf children who have used a CI > 4 months (28 of 36), and 78% of deaf children who completed NIRS testing on the day of CI initial activation (7 of 9). Therefore, NIRS can measure cortical responses in pediatric CI users, and has the potential to be a powerful adjunct to current CI assessment tools. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Modulation of mGlu2 Receptors, but Not PDE10A Inhibition Normalizes Pharmacologically-Induced Deviance in Auditory Evoked Potentials and Oscillations in Conscious Rats.

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    Abdallah Ahnaou

    Full Text Available Improvement of cognitive impairments represents a high medical need in the development of new antipsychotics. Aberrant EEG gamma oscillations and reductions in the P1/N1 complex peak amplitude of the auditory evoked potential (AEP are neurophysiological biomarkers for schizophrenia that indicate disruption in sensory information processing. Inhibition of phosphodiesterase (i.e. PDE10A and activation of metabotropic glutamate receptor (mGluR2 signaling are believed to provide antipsychotic efficacy in schizophrenia, but it is unclear whether this occurs with cognition-enhancing potential. The present study used the auditory paired click paradigm in passive awake Sprague Dawley rats to 1 model disruption of AEP waveforms and oscillations as observed in schizophrenia by peripheral administration of amphetamine and the N-methyl-D-aspartate (NMDA antagonist phencyclidine (PCP; 2 confirm the potential of the antipsychotics risperidone and olanzapine to attenuate these disruptions; 3 evaluate the potential of mGluR2 agonist LY404039 and PDE10 inhibitor PQ-10 to improve AEP deficits in both the amphetamine and PCP models. PCP and amphetamine disrupted auditory information processing to the first click, associated with suppression of the P1/N1 complex peak amplitude, and increased cortical gamma oscillations. Risperidone and olanzapine normalized PCP and amphetamine-induced abnormalities in AEP waveforms and aberrant gamma/alpha oscillations, respectively. LY404039 increased P1/N1 complex peak amplitudes and potently attenuated the disruptive effects of both PCP and amphetamine on AEPs amplitudes and oscillations. However, PQ-10 failed to show such effect in either models. These outcomes indicate that modulation of the mGluR2 results in effective restoration of abnormalities in AEP components in two widely used animal models of psychosis, whereas PDE10A inhibition does not.

  10. Study of psychiatric disorders and evaluation of their treatment using method of auditory evoked potential P300

    OpenAIRE

    Dapšys, Kastytis

    2011-01-01

    Recording and analysis of event-related potentials is safe and harmless method of evaluation of cognition and is suitable to follow the changes of cognitive processes induced by psychoactive drugs or other therapeutic procedures. The main aim of the work was to evaluate the influence of atypical antipsychotics risperidone and quetiapine and such nonpharmacological methods as electroconvulsive therapy and metaglossotherapy on the changes of information processing in the auditory system using e...

  11. Brainstem auditory evoked potential monitoring and neuro-endoscopy: Two tools to ensure hearing preservation and surgical success during microvascular decompression

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    Cheng-Chia Lee

    2014-06-01

    Conclusion: The results of this retrospective study emphasized the importance of BAEP monitoring and neuro-endoscopy during MVD. It is well known that BAEP monitoring can preserve hearing function, and the endoscope offers neurosurgeons a second look to identify the nerve root entry zone and confirms the position of the Teflon felt. These two tools are especially useful in difficult cases.

  12. Alterações dos potenciais evocados auditivos do tronco encefálico em pacientes com esclerose múltipla Alterations in early auditory evoked potentials in multiple sclerosis patients

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    Tania Mara Assis Lima

    2009-04-01

    Full Text Available A presença de alterações nos potenciais evocados auditivos do tronco encefálico (PEATE em indivíduos com doenças desmielinizantes sugere lesão do tronco encefálico. OBJETIVOS: O objetivo do presente estudo foi avaliar a incidência de alterações auditivas e dos PEATE em indivíduos com esclerose múltipla (EM. MATERIAL E MÉTODO: Participaram do estudo 16 pacientes do sexo feminino e 9 do sexo masculino com diagnóstico definido de EM. Testes audiométricos e pesquisa dos PEATE foram realizados em todos os indivíduos. Para a classificação dos PEATE utilizou-se a classificação proposta por Jerger (1986 na análise da morfologia das ondas. FORMA DE ESTUDO: Estudo de coorte contemporânea com corte transversal. RESULTADOS: Dos 50 PEATE realizados, 70% foram classificados como tipo I (resposta normal pela classificação de Jerger. Considerando-se como alterados os PEATE dos tipos II, III, IV ou V da classificação de Jerger em pelo menos um dos lados, encontrou-se 31,25% de alterações no sexo feminino e 44,44% no masculino, totalizando 36%. CONCLUSÕES: Estes achados enfatizam a relevância do estudo dos PEATE em casos de suspeita clínica de doenças desmielinizantes e naqueles com diagnóstico definido de EM.Alterations in early auditory evoked potentials (EAEP in individuals with demyelinating disease are suggestive of lesions in the brainstem. AIM: this study aims to evaluate the prevalence of hearing disorders and altered EAEP in multiple sclerosis (MS patients. MATERIALS AND METHOD: sixteen female and nine male patients with a defined diagnosis of multiple sclerosis took part in this study. All individuals underwent hearing and EAEP tests. The wave forms were categorized according to Jerger (1986. RESULTS: fifty EAEP tests were carried out; 70% were classified as type I (normal response according to Jerger's criteria. Altered EAEP results in at least one ear were classified into types II, III, IV or V according to Jerger

  13. The connections of the inferior colliculus and the organization of the brainstem auditory system in the greater horseshoe bat (Rhinolophus ferrumequinum).

    Science.gov (United States)

    Schweizer, H

    1981-09-01

    The connections of the inferior colliculus, the mammalian mid-brain auditory center, were determined in the greater horseshoe bat (Rhinolophus ferrumequinum), using the horseradish peroxidase method. In order to localize the auditory centers of this bat, brains were investigated with the aid of cell and fiber-stained material. The results show that most auditory centers are highly developed in this echolocating bat. However, the organization of the central auditory system does not generally differ from the mammalian scheme. This holds also for the organization of the superior olivary complex where a well-developed medial superior olivary nucleus was found. In addition to the ventral and dorsal nuclei of the lateral lemniscus a third well-developed nucleus has been defined which projects ipsilaterally to the inferior colliculus and which was called the intermediate nucleus of the lateral leminiscus. All nuclei of the central auditory pathway project ipsi-, contra-, or bilaterally to the central nucleus of the inferior colliculus with the exception of the medial nucleus of the trapezoid body and the medial geniculate body. The tonotopic organization of these projections and their possible functions are discussed in context with neurophysiological investigations.

  14. Assessment of auditory sensory processing in a neurodevelopmental animal model of schizophrenia-Gating of auditory-evoked potentials and prepulse inhibition

    DEFF Research Database (Denmark)

    Broberg, Brian Villumsen; Oranje, Bob; Yding, Birte

    2010-01-01

    of sensory information processing seen in schizophrenia patients, can be assessed by highly homologues methods in both humans and rodents, evident by the prepulse inhibition (PPI) of the auditory startle response and the P50 (termed P1 here) suppression paradigms. Treatment with the NMDA receptor antagonist...... (AEP), specifically by an increased P1 amplitude and reduced P2 (P200 in humans) gating. However, the treatment neither disrupted normal P1 gating nor reduced N1 (N100 in humans) amplitude, representing two phenomena that are usually found to be disturbed in schizophrenia. In conclusion, the current...... findings confirm measures of early information processing to show high resemblance between rodents and humans, and indicate that early postnatal PCP-treated rats show deficits in pre-attentional processing, which are distinct from those observed in schizophrenia patients....

  15. Bayesian Modeling of the Dynamics of Phase Modulations and their Application to Auditory Evoked Responses at Different Loudness Scales

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    Zeinab eMortezapouraghdam

    2016-01-01

    Full Text Available We study the effect of long-term habituation signatures of auditory selective attention reflected in the instantaneous phase information of the auditory event-related potentials (ERPs at four distinct stimuli levels of 60dB SPL, 70dB SPL, 80dB SPL and 90dB SPL. The analysis is based on the single-trial level. The effect of habituation can be observed in terms of the changes (jitter in the instantaneous phase information of ERPs. In particular, the absence of habituation is correlated with a consistently high phase synchronization over ERP trials.We estimate the changes in phase concentration over trials using a Bayesian approach, in which the phase is modeled as being drawn from a von Mises distribution with a concentration parameter which varies smoothly over trials. The smoothness assumption reflects the fact that habituation is a gradual process.We differentiate between different stimuli based on the relative changes and absolute values of the estimated concentration parameter using the proposed Bayesian model.

  16. Can the Loudness Dependence of Auditory Evoked Potentials and Suicidality Be Used to Differentiate between Depressive Patients with and without Bipolarity.

    Science.gov (United States)

    Park, Young-Min; Lee, Seung-Hwan

    2013-06-01

    This study aimed to test the hypothesis that the loudness dependence of auditory evoked potentials (LDAEP) can be used to predict the presence of bipolarity in patients with major depressive episodes. A cohort of 61 patients who met the criteria for major depressive disorder (MDD) following diagnosis using Axis I of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders-text revision, and who had no history of hypomanic or manic episodes was included in this study. The patients were stratified into two subgroups based on whether or not they achieved a positive score for the Korean versions of the Mood Disorder Questionnaire (K-MDQ). The LDAEP was evaluated by measuring the auditory event-related potentials before beginning medication with serotonergic agents. The Barratt Impulsiveness Scale (BIS) score was also higher for the positive screening group (81.24±11.87) than for the negative screening group (73.30±14.92; p=0.039, independent t-test). However, the LDAEP, Beck Depression Inventory, Hamilton Depression Rating Scale, Beck Hopelessness Scale (BHS), and Hamilton Anxiety Scale scores did not differ significantly between them. When binary logistic regression analysis was carried, the relationship between the positive or negative subgroups for K-MDQ and BIS or Beck Scale for Suicidal Ideation (BSS) score was also significant (respectively, p=0.017, p=0.038). We found that LDAEP was not significantly different between depressive patients with and without bipolarity. However, our study has revealed the difference between two subgroups based on whether or not they achieved a positive score for the K-MDQ in BIS or BSS score.

  17. Can the Loudness Dependence of Auditory Evoked Potentials and Suicidality Be Used to Differentiate between Depressive Patients with and without Bipolarity

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    Lee, Seung-Hwan

    2013-01-01

    Objective This study aimed to test the hypothesis that the loudness dependence of auditory evoked potentials (LDAEP) can be used to predict the presence of bipolarity in patients with major depressive episodes. Methods A cohort of 61 patients who met the criteria for major depressive disorder (MDD) following diagnosis using Axis I of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders-text revision, and who had no history of hypomanic or manic episodes was included in this study. The patients were stratified into two subgroups based on whether or not they achieved a positive score for the Korean versions of the Mood Disorder Questionnaire (K-MDQ). The LDAEP was evaluated by measuring the auditory event-related potentials before beginning medication with serotonergic agents. Results The Barratt Impulsiveness Scale (BIS) score was also higher for the positive screening group (81.24±11.87) than for the negative screening group (73.30±14.92; p=0.039, independent t-test). However, the LDAEP, Beck Depression Inventory, Hamilton Depression Rating Scale, Beck Hopelessness Scale (BHS), and Hamilton Anxiety Scale scores did not differ significantly between them. When binary logistic regression analysis was carried, the relationship between the positive or negative subgroups for K-MDQ and BIS or Beck Scale for Suicidal Ideation (BSS) score was also significant (respectively, p=0.017, p=0.038). Conclusion We found that LDAEP was not significantly different between depressive patients with and without bipolarity. However, our study has revealed the difference between two subgroups based on whether or not they achieved a positive score for the K-MDQ in BIS or BSS score. PMID:23798962

  18. The Corticofugal Effects of Auditory Cortex Microstimulation on Auditory Nerve and Superior Olivary Complex Responses Are Mediated via Alpha-9 Nicotinic Receptor Subunit.

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    Cristian Aedo

    Full Text Available The auditory efferent system is a complex network of descending pathways, which mainly originate in the primary auditory cortex and are directed to several auditory subcortical nuclei. These descending pathways are connected to olivocochlear neurons, which in turn make synapses with auditory nerve neurons and outer hair cells (OHC of the cochlea. The olivocochlear function can be studied using contralateral acoustic stimulation, which suppresses auditory nerve and cochlear responses. In the present work, we tested the proposal that the corticofugal effects that modulate the strength of the olivocochlear reflex on auditory nerve responses are produced through cholinergic synapses between medial olivocochlear (MOC neurons and OHCs via alpha-9/10 nicotinic receptors.We used wild type (WT and alpha-9 nicotinic receptor knock-out (KO mice, which lack cholinergic transmission between MOC neurons and OHC, to record auditory cortex evoked potentials and to evaluate the consequences of auditory cortex electrical microstimulation in the effects produced by contralateral acoustic stimulation on auditory brainstem responses (ABR.Auditory cortex evoked potentials at 15 kHz were similar in WT and KO mice. We found that auditory cortex microstimulation produces an enhancement of contralateral noise suppression of ABR waves I and III in WT mice but not in KO mice. On the other hand, corticofugal modulations of wave V amplitudes were significant in both genotypes.These findings show that the corticofugal modulation of contralateral acoustic suppressions of auditory nerve (ABR wave I and superior olivary complex (ABR wave III responses are mediated through MOC synapses.

  19. Potencial evocado cognitivo e desordem de processamento auditivo em crianças com distúrbios de leitura e escrita Cognitive evoked potentials and central auditory processing in children with reading and writing disorders

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    Gislaine Richter Minhoto Wiemes

    2012-06-01

    Full Text Available As dificuldades na aprendizagem escolar muitas vezes podem ser causadas por uma alteração do Processamento Auditivo - PA. OBJETIVO: Identificar se acima da média dos valores de latência do P300, num grupo de indivíduos com Distúrbio de Leitura e Escrita, também seriam encontradas alterações no teste Staggered Spondaic Word - SSW e no teste de Fala no Ruído que sugerissem Desordem do Processamento Auditivo - DPA. MATERIAL E MÉTODOS: Estudo de coorte transversal. Foram avaliados 21 indivíduos com distúrbio de leitura e escrita, idade entre 7 e 14 anos. RESULTADOS: Todos apresentaram resultados normais no exame otorrinolaringológico, na avaliação audiológica e Potencial Evocado Auditivo de Tronco Encefálico. Fazendo-se a média aritmética de todos os valores de latência do P300 obtidos, chegou-se à média de 334,25 ms, sendo divididos em dois grupos: grupo "A", com média da latência acima de 335 ms, e "B", com latência abaixo de 335 ms. Nos indivíduos do grupo "A", foram realizados os testes SSW e Fala no Ruído. CONCLUSÃO:O presente estudo pode concluir que foram encontradas alterações nos testes de fala dicótica (SSW e de Fala no Ruído no grupo de indivíduos com Distúrbio da Escrita e Leitura com valores de latência do P300 acima de 335 ms, sugerindo DPA.Learning disorders are often magnified by auditory processing disorders (APD. OBJECTIVE: This paper aims to verify whether individuals with reading and writing disorders and P300 latencies above the average also present altered Staggered Spondaic Word (SSW and speech-in-noise test results suggestive of APD. MATERIALS AND METHODS: This is a cross-sectional cohort study. Twenty-one individuals with reading and writing disorders aged between 7 and 14 years were enrolled. RESULTS: All subjects had normal findings on ENT examination, audiological tests, and brainstem auditory evoked potentials. The average P300 latency (334,25 ms of all patients was picked as a cutoff

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

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    Alfredo Lopes Pereira Filho

    2004-01-01

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

  1. Potenciales provocados auditivos en niños con riesgo neonatal de hipoacusia Auditory evoked potentials in children at neonatal risk for hypoacusis

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    Saúl Garza Morales

    1997-02-01

    Full Text Available Los potenciales provocados auditivos del tallo cerebral (PPATC son un método sencillo y no invasor de evaluación de la función auditiva, que se utiliza ampliamente en niños para detectar tempranamente hipoacusia. Entre abril de 1992 y mayo de 1994, se estudiaron 400 niños mexicanos que presentaban, al menos, un factor de riesgo neonatal de hipoacusia. La media de la edad de los niños estudiados fue 6,6 meses y la media de la edad gestacional al nacer, 35,1 semanas. El 51% de ellos fueron tratados con amikacina. Se registraron 1 427 factores de riesgo (3,5 por niño, entre los que predominaron la exposición a ototóxicos, la hiperbilirrubinemia y el peso al nacer menor de 1 500 g. En 27% se encontraron alteraciones auditivas de tipo periférico y en 13%, ausencia de respuesta a estímulos auditivos. El bajo peso y la menor edad gestacional al nacer, la concentración máxima de bilirrubina en el suero, la presencia de sepsis, la hemorragia subependimaria o intraventricular, la ventilación mecánica y la exposición a ototóxicos se asociaron significativamente con la presencia de hipoacusia grave o profunda.Auditory evoked potentials of the brain stem (AEPBS provide a simple, noninvasive method of evaluating hearing function and have been widely used for early detection of hypoacusis in children. Between April 1992 and May 1994, a study was done of 400 Mexican children who presented at least one neonatal risk factor for hearing impairment. The average age of the children studied was 6.6 months and their average gestational age at birth was 35.1 weeks. Just over half of them (51% had been treated with amikacin. The study found 1 427 risk factors (3.5 per child, the most common ones being exposure to ototoxic substances, hyperbilirubinemia, and birthweight of less that 1 500 g. In 27% of the children, peripheral auditory changes were found, and 13% did not respond to auditory stimuli. Low birthweight and young gestational age at birth, high

  2. Early changes in auditory function as a result of platinum chemotherapy: use of extended high-frequency audiometry and evoked distortion product otoacoustic emissions.

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    Knight, Kristin R; Kraemer, Dale F; Winter, Christiane; Neuwelt, Edward A

    2007-04-01

    The objective is to describe progressive changes in hearing and cochlear function in children and adolescents treated with platinum-based chemotherapy and to begin preliminary evaluation of the feasibility of extended high-frequency audiometry and distortion product otoacoustic emissions for ototoxicity monitoring in children. Baseline and serial measurement of conventional pure-tone audiometry (0.5 to 8 kHz) and evoked distortion product otoacoustic emissions (DPOAEs) were conducted for 32 patients age 8 months to 20 years who were treated with cisplatin and/or carboplatin chemotherapy. Seventeen children also had baseline and serial measurement of extended high-frequency (EHF) audiometry (9 to 16 kHz). Audiologic data were analyzed to determine the incidence of ototoxicity using the American Speech-Language-Hearing Association criteria, and the relationships between the different measures of ototoxicity. Of the 32 children, 20 (62.5%) acquired bilateral ototoxicity in the conventional frequency range during chemotherapy treatment, and 26 (81.3%) had bilateral decreases in DPOAE amplitudes and dynamic range. Of the 17 children with EHF audiometry results, 16 (94.1%) had bilateral ototoxicity in the EHF range. Pilot data suggest that EHF thresholds and DPOAEs show ototoxic changes before hearing loss is detected by conventional audiometry. EHF audiometry and DPOAEs have the potential to reveal earlier changes in auditory function than conventional frequency audiometry during platinum chemotherapy in children.

  3. Relationship between Serotonergic Dysfunction Based on Loudness Dependence of Auditory-Evoked Potentials and Suicide in Patients with Major Depressive Disorder.

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    Park, Young-Min

    2015-10-01

    The relationship between suicidality and the loudness dependence of auditory-evoked potentials (LDAEP) remains controversial. This article reviews the literature related to the LDAEP and suicide in patients with major depressive disorder, and suggests future research directions. Serotonergic dysfunction in suicidality seems to be more complicated than was originally thought. Studies of suicide based on the LDAEP have produced controversial results, but it is possible that these are due to differences in study designs and the smallness of samples. For example, some studies have evaluated suicide ideation and the LDAEP, while others have evaluated suicide attempts and the LDAEP. Furthermore, some of the latter studies enrolled acute suicide attempters, while others enrolled those with the history of previous suicide attempts, irrespective of whether these were acute or chronic. Thus, a more robust study design is needed in future studies, for example by evaluating the LDAEP immediately after a suicide attempt rather than in those with a history of suicide attempts and suicide ideation in order to reduce bias. Moreover, genuine suicide attempt, self-injurious behaviors, and faked suicide attempt need to be discriminated in the future.

  4. Auditory evoked potentials in premature and full-term infants Potenciais evocados auditivos em lactentes pré-termo e a termo

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    Maria Angélica de Almeida Porto

    2011-10-01

    Full Text Available Accurate information about type, degree, and configuration of hearing loss are necessary for successful audiological early interventions. Auditory brainstem response with tone burst stimuli (TB ABR and auditory steady-state response (ASSR exams provide this information. AIM: To analyze the clinical applicability of TB ABR and ASSR at 2 kHz in infants, comparing responses in full-term and premature neonates. MATERIAL AND METHOD: The study was cross-sectional, clinical and experimental. Subjects consisted of 17 premature infants and 19 full-term infants. TB ABR and ASSR exams at 2000 Hz were done during natural sleep. RESULTS: The electrophysiological minimum response obtained with TB ABR was 32.4 dBnHL (52.4 dBSPL; the ASSR minimum was 13.8 dBHL (26.4 dBSPL. The exams required 21.1 min and 22 min, respectively. Premature and full-term infant responses showed no statistically significant differences, except for auditory steady-state response duration. CONCLUSIONS: Both exams have clinical applicability at 2 kHz in infants, with 20 min of duration, on average. In general, there are no differences between premature and full-term individuals.O sucesso de uma intervenção audiológica precoce depende de informações precisas quanto ao tipo, grau e configuração da perda auditiva. O potencial evocado auditivo de tronco encefálico com o estímulo tone burst (PEATE TB e a resposta auditiva de estado estável (RAEE proporcionam tais informações. OBJETIVO: Investigar a aplicabilidade clínica, em lactentes, do PEATE TB e da RAEE na frequência de 2 kHz, comparando as respostas dos lactentes nascidos a termo e prétermo. MATERIAL E MÉTODO: O estudo (transversal, clínico e experimental foi realizado com uma casuística de 17 lactentes pré-termo e 19 a termo submetidos ao PEATE TB e RAEE em 2000 Hz. RESULTADOS: A resposta eletrofisiológica mínima obtida com o PEATE TB foi de 32,4 dBnNA (52,4 dBNPS e com a RAEE de 13,8 dBNA (26,4 dBNPS, com dura

  5. Source imaging of P300 auditory evoked potentials and clinical correlations in patients with posttraumatic stress disorder.

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    Bae, Kyung-Yeol; Kim, Do-Won; Im, Chang-Hwan; Lee, Seung-Hwan

    2011-12-01

    Posttraumatic stress disorder (PTSD) is associated with abnormal information processing. The P300 component of event-related potentials (ERPs) is known to be a useful marker of information processing. The purposes of this study were to determine the P300 current source density in PTSD patients, and its relationship with symptom severity. ERPs were recorded in 30 PTSD patients and 33 healthy controls while participants were performing the auditory oddball task. We compared P300 current source density data--obtained by standardized low-resolution brain electromagnetic tomography (sLORETA)--between the two groups. The correlation between P300 current source density and clinical symptoms (as evaluated using the Korean version of the Structured Interview for PTSD--K-SIPS and Davidson Trauma Scale--K-DTS) was conducted. In PTSD patients, the current source density of P300 is significantly reduced in the inferior frontal gyrus, precentral gyrus, insula, and anterior cingulate compared to healthy controls. Total K-DTS scores were correlated with the P300 current source density in the posterior cingulate gyrus. The K-SIP B items (re-experiencing) and K-SIB D items (increased arousal) were positively correlated with P300 current source densities in several brain regions located in the frontal, parietal, and temporal lobe (psource densities in the superior and middle frontal gyri in the frontal lobes (psource densities reflected the pathophysiology of PTSD patients. PTSD symptoms were related to different neural activities, depending on their symptom characteristics. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Latência do potencial evocado auditivo P300 em idosos P300 auditory evoked potential latency in elderly

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    Maria José Santos Cóser

    2010-06-01

    Full Text Available Distúrbios auditivos corticais no idoso podem ser avaliados pelo P300. A falta de valores contemporâneos de referência da latência do P300 em idosos saudáveis motivou este estudo. OBJETIVO: Estimar o efeito da idade sobre a latência do P300 em um grupo de idosos. MATERIAL E MÉTODO: Foram estudados 62 idosos, com limiares tonais até 40 dBNA nas frequências de 1000 e 2000 Hz, divididos em grupos de acordo com a idade (60-64, 65-69 e 70-74 anos. Foram avaliados pela pesquisa da latência do P300 em resposta ao estímulo raro de 2000 Hz e ao frequente de 1000 Hz, ambos na intensidade de 80 dBNA. FORMA DE ESTUDO: Clínico, corte transversal observacional, individual comparado, prospectivo. RESULTADOS: A latência no Grupo 60 foi 337,26 ms (DP 11,31, no Grupo 65 foi 351,86 ms (DP 29,05 e no Grupo 70 foi 370,19ms (DP 23,40. A regressão linear dos valores de latência do P300 mostrou um aumento de 2,85 ms por ano de idade. A análise estatística mostrou que os resultados obtidos foram significativos. CONCLUSÃO: A latência do P300 aumenta com a idade em uma taxa de 2,85 ms por ano entre a idade de 60 e 74 anos.Auditory cortical disorders in the elderly can be assessed by the P300. The lack of contemporary reference values of P300 latency in healthy elderly motivated this study. AIM: To estimate the effect of age on P300 latency in a group of elderly. METHODS: We studied 62 elderly patients with pure tone thresholds up to 40 dB HL at the frequencies of 1000 and 2000 Hz, divided into groups according to age (60-64, 65-69 and 70-74 years. Were assessed by the P300 latency in response to the rare stimulus of 2000 Hz and 1000 Hz frequencies, both in the intensity of 80 dB HL. STUDY DESIGN: clinical, cross-sectional observational individual compared prospective. RESULTS: The latency in Group 60 was 337.26 ms (SD 11.31 in Group 65 was 351.86 ms (SD 29.05 and in Group 70 it was 370.19 ms (SD 23.40. The linear regression of the values of P300 latency

  7. Protocolo para captação dos potenciais evocados auditivos de longa latência Protocol to collect late latency auditory evoked potentials

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    Luzia Maria Pozzobom Ventura

    2009-12-01

    Full Text Available Os potenciais evocados auditivos de longa latência (PEALLs se referem a uma série de mudanças elétricas, ocorridas no sistema nervoso central, resultante da estimulação da via sensorial auditiva. Muitos estudos abordam o uso destes potenciais, controlando o artefato gerado pelo movimento ocular com a utilização de equipamentos com grande número de canais. Porém, na prática clínica nacional, a realidade é diferente, havendo disponibilidade de equipamentos com número reduzido de canais. OBJETIVO: Comparar dois métodos de controle do artefato gerado pelo movimento ocular durante a captação dos PEALLs usando dois canais de registro. MATERIAL E MÉTODO: Estudo prospectivo pela aplicação de dois métodos de captação dos PEALLs (subtração do artefato ocular e controle do limite de rejeição em 10 adultos ouvintes normais. RESULTADOS: Não foi observada diferença estatisticamente significante entre os valores de latência obtidos com o uso dos dois métodos, apenas entre os valores de amplitude. CONCLUSÃO: Os dois métodos foram eficientes para a captação dos PEALLs e para o controle do artefato do movimento ocular. O método do controle do limite de rejeição promoveu maiores valores de amplitude.Long Latency Auditory Evoked Potentials (LLAEP represents a number of electrical changes occurring in the central nervous system, resulting from stimulation of the auditory sensorial pathways. Many studies approach the use of these potentials controlling the artifact created by eye movement with the use of equipment with a large number of channels. However, what happens is very different in Brazilian clinical practice, where the equipment used has a very limited number of channels. AIM: to compare the two methods used to control the artifacts created by eye movements during LLAEP capture using two recording channels. MATERIALS AND METHODS: this is a prospective study with the application of two LLAEP capturing methods (eye artifact

  8. The frequency modulated auditory evoked response (FMAER, a technical advance for study of childhood language disorders: cortical source localization and selected case studies

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    Duffy Frank H

    2013-01-01

    Full Text Available Abstract Background Language comprehension requires decoding of complex, rapidly changing speech streams. Detecting changes of frequency modulation (FM within speech is hypothesized as essential for accurate phoneme detection, and thus, for spoken word comprehension. Despite past demonstration of FM auditory evoked response (FMAER utility in language disorder investigations, it is seldom utilized clinically. This report's purpose is to facilitate clinical use by explaining analytic pitfalls, demonstrating sites of cortical origin, and illustrating potential utility. Results FMAERs collected from children with language disorders, including Developmental Dysphasia, Landau-Kleffner syndrome (LKS, and autism spectrum disorder (ASD and also normal controls - utilizing multi-channel reference-free recordings assisted by discrete source analysis - provided demonstratrions of cortical origin and examples of clinical utility. Recordings from inpatient epileptics with indwelling cortical electrodes provided direct assessment of FMAER origin. The FMAER is shown to normally arise from bilateral posterior superior temporal gyri and immediate temporal lobe surround. Childhood language disorders associated with prominent receptive deficits demonstrate absent left or bilateral FMAER temporal lobe responses. When receptive language is spared, the FMAER may remain present bilaterally. Analyses based upon mastoid or ear reference electrodes are shown to result in erroneous conclusions. Serial FMAER studies may dynamically track status of underlying language processing in LKS. FMAERs in ASD with language impairment may be normal or abnormal. Cortical FMAERs can locate language cortex when conventional cortical stimulation does not. Conclusion The FMAER measures the processing by the superior temporal gyri and adjacent cortex of rapid frequency modulation within an auditory stream. Clinical disorders associated with receptive deficits are shown to demonstrate absent

  9. 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.

  10. 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

  11. Effect of auditory evoked potential-guided anaesthesia on consumption of anaesthetics and early postoperative cognitive dysfunction: a randomised controlled trial.

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    Jildenstål, Pether K; Hallén, Jan L; Rawal, Narinder; Gupta, Anil; Berggren, Lars

    2011-03-01

    Post-operative cognitive dysfunction (POCD) after non-cardiac surgery is a well known problem in some categories of patients. This study aims to evaluate the influence of auditory evoked potential (AEP)-guided anaesthesia on the requirement for anaesthetic drugs and their influence on POCD. Four hundred and fifty patients aged between 18 and 92 years scheduled for ophthalmic surgery under general anaesthesia were assigned randomly to one of two groups. In group A (AEP group), the depth of anaesthesia (DoA) was aimed at an AEP index (AAI) between 15 and 25. In group C (control group), DoA was guided by clinical signs. Hypotension was treated with fluids and vasopressors using a standardised algorithm. A mini-mental test and the Cognitive Failure Questionnaire were used to evaluate cognitive function. Anaesthetic drug requirements were significantly lower in group A than in group C: propofol 92.5 ± 26.5 vs. 103.8 ± 39.5 mg (P = <0.001) and desflurane end-tidal concentration 2.5 ± 0.58 vs. 3.3 ± 0.79% (P < 0.001). In group A, 36 patients (16%) received additional fluids and vasopressors compared to 65 patients (29%) in group C (P < 0.01). AAI values differed significantly between the groups: 18 (11-21) in group A vs. 12 (10-19) in group C (P < 0.001). The number of patients with POCD was 16 in group C compared to two in group A (P < 0.001) at day 1 post-operation. AEP monitoring allows dose reduction of anaesthetic agents, leading to better cardiovascular stability and decreased requirements for intra-operative fluids and vasopressors. Cognitive decline seen following minor ophthalmic surgery, even when anaesthesia is assessed clinically, is short-lived with no long-term sequelae.

  12. An automatic algorithm for blink-artifact suppression based on iterative template matching: application to single channel recording of cortical auditory evoked potentials

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    Valderrama, Joaquin T.; de la Torre, Angel; Van Dun, Bram

    2018-02-01

    Objective. Artifact reduction in electroencephalogram (EEG) signals is usually necessary to carry out data analysis appropriately. Despite the large amount of denoising techniques available with a multichannel setup, there is a lack of efficient algorithms that remove (not only detect) blink-artifacts from a single channel EEG, which is of interest in many clinical and research applications. This paper describes and evaluates the iterative template matching and suppression (ITMS), a new method proposed for detecting and suppressing the artifact associated with the blink activity from a single channel EEG. Approach. The approach of ITMS consists of (a) an iterative process in which blink-events are detected and the blink-artifact waveform of the analyzed subject is estimated, (b) generation of a signal modeling the blink-artifact, and (c) suppression of this signal from the raw EEG. The performance of ITMS is compared with the multi-window summation of derivatives within a window (MSDW) technique using both synthesized and real EEG data. Main results. Results suggest that ITMS presents an adequate performance in detecting and suppressing blink-artifacts from a single channel EEG. When applied to the analysis of cortical auditory evoked potentials (CAEPs), ITMS provides a significant quality improvement in the resulting responses, i.e. in a cohort of 30 adults, the mean correlation coefficient improved from 0.37 to 0.65 when the blink-artifacts were detected and suppressed by ITMS. Significance. ITMS is an efficient solution to the problem of denoising blink-artifacts in single-channel EEG applications, both in clinical and research fields. The proposed ITMS algorithm is stable; automatic, since it does not require human intervention; low-invasive, because the EEG segments not contaminated by blink-artifacts remain unaltered; and easy to implement, as can be observed in the Matlab script implemeting the algorithm provided as supporting material.

  13. 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.

  14. Evoked potentials in pediatric cerebral malaria

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    Minal Bhanushali

    2011-08-01

    Full Text Available Cortical evoked potentials (EP provide localized data regarding brain function and may offer prognostic information and insights into the pathologic mechanisms of malariamediated cerebral injury. As part of a prospective cohort study, we obtained somatosensory evoked potentials (SSEPs and brainstem auditory EPs (AEPs within 24 hours of admission on 27 consecutive children admitted with cerebral malaria (CM. Children underwent follow-up for 12 months to determine if they had any long term neurologic sequelae. EPs were obtained in 27 pediatric CM admissions. Two children died. Among survivors followed an average of 514 days, 7/25 (28.0% had at least one adverse neurologic outcome. Only a single subject had absent cortical EPs on admission and this child had a good neurologic outcome. Among pediatric CM survivors, cortical EPs are generally intact and do not predict adverse neurologic outcomes. Further study is needed to determine if alterations in cortical EPs can be used to predict a fatal outcome in CM.

  15. Auditory Neuropathy: Findings of Behavioral, Physiological and Neurophysiological Tests

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    Mohammad Farhadi

    2006-12-01

    Full Text Available Background and Aim: Auditory neuropathy (AN can be diagnosed by abnormal auditory brainstem response (ABR, in the presence of normal cochlear microphonic (CM and otoacoustic emissions (OAEs.The aim of this study was to investigate the ABR and other electrodiagnostic test results of 6 patients suspicious to AN with problems in speech recognition. Materials and Methods: this cross sectional study was conducted on 6 AN patients with different ages evaluated by pure tone audiometry, speech discrimination score (SDS , immittance audiometry. ElectroCochleoGraphy , ABR, middle latency response (MLR, Late latency response (LLR, and OAEs. Results: Behavioral pure tone audiometric tests showed moderate to profound hearing loss. SDS was so poor which is not in accordance with pure tone thresholds. All patients had normal tympanogram but absent acoustic reflexes. CMs and OAEs were within normal limits. There was no contra lateral suppression of OAEs. None of cases had normal ABR or MLR although LLR was recorded in 4. Conclusion: All patients in this study are typical cases of auditory neuropathy. Despite having abnormal input, LLR remains normal that indicates differences in auditory evoked potentials related to required neural synchrony. These findings show that auditory cortex may play a role in regulating presentation of deficient signals along auditory pathways in primary steps.

  16. Neurotrophic factor intervention restores auditory function in deafened animals

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    Shinohara, Takayuki; Bredberg, Göran; Ulfendahl, Mats; Pyykkö, Ilmari; Petri Olivius, N.; Kaksonen, Risto; Lindström, Bo; Altschuler, Richard; Miller, Josef M.

    2002-02-01

    A primary cause of deafness is damage of receptor cells in the inner ear. Clinically, it has been demonstrated that effective functionality can be provided by electrical stimulation of the auditory nerve, thus bypassing damaged receptor cells. However, subsequent to sensory cell loss there is a secondary degeneration of the afferent nerve fibers, resulting in reduced effectiveness of such cochlear prostheses. The effects of neurotrophic factors were tested in a guinea pig cochlear prosthesis model. After chemical deafening to mimic the clinical situation, the neurotrophic factors brain-derived neurotrophic factor and an analogue of ciliary neurotrophic factor were infused directly into the cochlea of the inner ear for 26 days by using an osmotic pump system. An electrode introduced into the cochlea was used to elicit auditory responses just as in patients implanted with cochlear prostheses. Intervention with brain-derived neurotrophic factor and the ciliary neurotrophic factor analogue not only increased the survival of auditory spiral ganglion neurons, but significantly enhanced the functional responsiveness of the auditory system as measured by using electrically evoked auditory brainstem responses. This demonstration that neurotrophin intervention enhances threshold sensitivity within the auditory system will have great clinical importance for the treatment of deaf patients with cochlear prostheses. The findings have direct implications for the enhancement of responsiveness in deafferented peripheral nerves.

  17. 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.

  18. 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.

  19. Cortical Maturation and Behavioral Outcomes in Children with Auditory Neuropathy Spectrum Disorder

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    Sharma, Anu; Cardon, Garrett; Martin, Kathryn; Roland, Peter

    2013-01-01

    Objective Auditory Neuropathy Spectrum Disorder (ANSD) affects nearly 10% of patients with sensorineural hearing loss. While many studies report abnormalities at the level of the cochlea, auditory nerve and brainstem in children with ANSD, much less is known about their cortical development. We examined central auditory maturation in 21 children with ANSD. Design Morphology, latency and amplitude of the P1 Cortical Auditory Evoked Potential (CAEP) were used to assess auditory cortical maturation. Children’s scores on a measure of auditory skill development (IT-MAIS) were correlated with CAEPs. Study Sample Participants were 21 children with ANSD. All were hearing aid users. Results Children with ANSD exhibited differences in central auditory maturation. Overall, two-thirds of children revealed present P1 CAEP responses. Of these, approximately one third (38%) showed normal P1 response morphology, latency and amplitude, while another third (33%) showed delayed P1 response latencies and significantly smaller amplitudes. The remaining children (29%) revealed abnormal or absent P1 responses. Overall, P1 responses were significantly correlated with auditory skill development. Conclusions Our results suggest that P1 CAEP responses may be: (i) a useful indicator of the extent to which neural dys-synchrony disrupts cortical development, (ii) a good predictor of behavioral outcome in children with ANSD. PMID:21265637

  20. Multimodality evoked potentials in HTLV-I associated myelopathy.

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    Kakigi, R; Shibasaki, H; Kuroda, Y; Endo, C; Oda, K; Ikeda, A; Hashimoto, K

    1988-08-01

    Multimodality evoked potentials (EPs) consisting of somatosensory EPs (SEPs), visual EPs (VEPs) and brainstem auditory EPs (BAEPs) were studied in 16 cases with HTLV-I associated myelopathy (HAM). Median nerve SEPs were normal in all cases. In posterior tibial nerve SEPs, the potential recorded at the 12th thoracic spinal process was normal in every case but cortical components were significantly prolonged in 10 cases, although five of these showed no sensory impairment. BAEPs were normal in every case whose hearing was intact, but VEPs were abnormal in two cases whose visual acuities were normal. The present results in HAM indicate predominant lesion in the thoracic cord, and might also suggest some subclinical lesion in the visual pathway.

  1. Maturation of cortical auditory evoked potentials (CAEPs) to speech recorded from frontocentral and temporal sites: three months to eight years of age.

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    Shafer, Valerie L; Yu, Yan H; Wagner, Monica

    2015-02-01

    The goal of the current analysis was to examine the maturation of cortical auditory evoked potentials (CAEPs) from three months of age to eight years of age. The superior frontal positive-negative-positive sequence (P1, N2, P2) and the temporal site, negative-positive-negative sequence (possibly, Na, Ta, Tb of the T-complex) were examined. Event-related potentials were recorded from 63 scalp sites to a 250-ms vowel. Amplitude and latency of peaks were measured at left and right frontal sites (near Fz) and at left and right temporal sites (T7 and T8). In addition, the largest peak (typically corresponding to P1) was selected from global field power (GFP). The results revealed a large positive peak (P1) easily identified at frontal sites across all ages. The N2 emerged after 6 months of age and the following P2 between 8 and 30 months of age. The latencies of these peaks decreased exponentially with the most rapid decrease observed for P1. For amplitude, only P1 showed a clear relationship with age, becoming more positive in a somewhat linear fashion. At the temporal sites only a negative peak, which might be Na, was clearly observed at both left and right sites in children older than 14 months and peaking between 100 and 200 ms. P1 measures at frontal sites and Na peak latencies were moderately correlated. The temporal negative peak latency showed a different maturational timecourse (linear in nature) than the P1 peak, suggesting at least partial independence. Distinct Ta (positive) and Tb (negative) peaks, following Na and peaking between 120 and 220 ms were not consistently found in most age groups of children, except Ta which was present in 7 year olds. Future research, which includes manipulation of stimulus factors, and use of modeling techniques will be needed to explain the apparent, protracted maturation of the temporal site measures in the current study. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Audiometria de tronco encefálico (abr: o uso do mascaramento na avaliação de indivíduos portadores de perda auditiva unilateral Auditory brainstem response (abr: use of masking in unilateral hearing loss patients

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    Melissa M. T. Toma

    2003-06-01

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

  3. Evaluation of an auditory assessment protocol for Chinese infants with nonsyndromic cleft lip and/or palate.

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    Yang, Frank F; McPherson, Bradley; Shu, Huang

    2012-09-01

    To objectively investigate the auditory status of mainland Chinese infants with nonsyndromic cleft lip and/or palate and to evaluate an auditory assessment protocol for this group. Prospective cohort case review. A total of 42 Chinese infants with nonsyndromic cleft lip and/or palate aged 6 to 24 months. The hearing profiles of participants were acquired using otoscopy, tympanometry, transient-evoked otoacoustic emissions, and auditory brainstem response estimated hearing threshold. The efficiency of the current audiological test battery was analyzed also. Sixty-four (64.2) percent of infants with nonsyndromic cleft lip and/or palate (55.9% of ears) were suspected to have middle ear disorder, and 85.7% of all subjects (83.3% of ears) were found to have hearing loss. Of those with confirmed loss, the overall mean auditory brainstem response estimated air-conduction hearing threshold was 53.5 ± 13.6 decibel normal hearing level [db nHL]. Using auditory brainstem response thresholds as a reference standard, the diagnostic agreement with the other assessment tools for normal/abnormal results was otoscopy, 69% (κ  =  .57); tympanometry, 66.7% (κ  =  .53); and transient-evoked otoacoustic emissions, 80% (κ  =  .64). The high prevalence of middle ear disease and hearing loss in mainland Chinese infants with nonsyndromic cleft lip and/or palate in this study was in contrast to previous studies of older age groups of Chinese children conducted in Hong Kong and Singapore. The audiological assessment protocol used in our study could provide useful information; although, modifications may be necessary to ensure a complete diagnostic overview for children with craniofacial clefts.

  4. 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.

  5. Focal brainstem gliomas

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    Sabbagh, Abdulrahman J.; Alaqeel, Ahmed M.

    2015-01-01

    Improved neuronavigation guidance as well as intraoperative imaging and neurophysiologic monitoring technologies have enhanced the ability of neurosurgeons to resect focal brainstem gliomas. In contrast, diffuse brainstem gliomas are considered to be inoperable lesions. This article is a continuation of an article that discussed brainstem glioma diagnostics, imaging, and classification. Here, we address open surgical treatment of and approaches to focal, dorsally exophytic, and cervicomedullary brainstem gliomas. Intraoperative neuronavigation, intraoperative neurophysiologic monitoring, as well as intraoperative imaging are discussed as adjunctive measures to help render these procedures safer, more acute, and closer to achieving surgical goals. PMID:25864061

  6. Potenciais evocados auditivos de longa latência: um estudo comparativo entre hemisférios cerebrais Long auditory evoked potential: comparative study between cerebral hemispheres

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    Ana Claudia F. Frizzo

    2001-09-01

    Full Text Available Introdução: A partir dos primeiros registros de atividades elétricas cerebrais (EEG em resposta à apresentação de estímulos auditivos em seres humanos, durante a década de 30, pôde-se observar os potenciais evocados auditivos de longa latência - PEALLs (Mendel, 1989. Desde então, muitas pesquisas têm sido realizadas enfatizando o estudo do sistema auditivo em sua totalidade (periférico e central. Considerando a diferenciação funcional entre os hemisférios cerebrais, o presente estudo procurou identificar evidências eletrofisiológicas que constatem diferenciações interhemisféricas. Forma de estudo: Prospectivo clínico randomizado. Objetivo: O objetivo principal foi verificar a ocorrência de possíveis diferenciações entre os PEALLs dos hemisférios direito (Cz/A2 e esquerdo (Cz/A1 em um grupo de normoouvintes entre 8 e 18 anos de idade, por meio da análise comparativa dos registros dos PEALLs, quanto à latência e amplitude. Resultados: Não foram observadas diferenças estatisticamente significantes entre as medidas, exceto para o componente P2, na população masculina. Porém, não se pode negar a diferenciação funcional entre os hemisférios e deve-se considerar essa variável durante a realização da pesquisa dos PEALLs. Conclusão: Contudo, futuros trabalhos ainda serão necessários, com amostras maiores ou até mesmo com diferentes posicionamentos de eletrodos, a fim de verificarmos a existência ou não de evidências eletrofisiológicas que constatam essas diferenciações, garantindo a aplicação mais segura e efetiva deste método.Introduction: Since of the first registration of cerebral electric activities (EEG in response to the presentation hearing stimulus in human, decade 30‘s, can be observed the late components or long latency auditory evoked potentials - LLAEP (Mendel, 1989. Ever since, a lot of number of researches have been performed emphasizing the study of the hearing system (the ear and

  7. Identification of neonatal hearing impairment: evaluation of transient evoked otoacoustic emission, distortion product otoacoustic emission, and auditory brain stem response test performance.

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    Norton, S J; Gorga, M P; Widen, J E; Folsom, R C; Sininger, Y; Cone-Wesson, B; Vohr, B R; Mascher, K; Fletcher, K

    2000-10-01

    The purpose of this study was to compare the performance of transient evoked otoacoustic emissions (TEOAEs), distortion product otoacoustic emissions (DPOAEs), and auditory brain stem responses (ABRs) as tools for identification of neonatal hearing impairment. A total of 4911 infants including 4478 graduates of neonatal intensive care units, 353 well babies with one or more risk factors for hearing loss (Joint Committee on Infant Hearing, 1994) and 80 well babies without risk factor who did not pass one or more neonatal test were targeted as the potential subject pool on which test performance would be assessed. During the neonatal period, they were evaluated using TEOAEs in response to an 80 dB pSPL click, DPOAE responses to two stimulus conditions (L1 = L2 = 75 dB SPL and L1 = 65 dB SPL L2 = 50 dB SPL), and ABR elicited by a 30 dB nHL click. In an effort to describe test performance, these "at-risk" infants were asked to return for behavioral audiologic assessments, using visual reinforcement audiometry (VRA) at 8 to 12 mo corrected age, regardless of neonatal test results. Sixty-four percent of these subjects returned and reliable VRA data were obtained on 95.6% of these returnees. This approach is in contrast to previous studies in which, by necessity, efforts were made to follow only those infants who "failed" the neonatal screening tests. The accuracy of the neonatal measures in predicting hearing status at 8 to 12 mo corrected age was determined. Only those infants who provided reliable, monaural VRA test results were included in the analysis. Separate analyses were performed without regard to intercurrent events (i.e., events between the neonatal and VRA tests that could cause their results to disagree), and then after accounting for the possible influence of intercurrent events such as otitis media and late-onset or progressive hearing loss. Low refer rates were achieved for the stopping criteria used in the present study, especially when a protocol

  8. Auditory findings and electrophysiologics in individuals with G/BBB syndrome.

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    Cassab, Tatiana Vialôgo; Zanchetta, Sthella; Giacheti, Célia Maria; Zorzetto, Neivo Luiz; Richieri-Costa, Antonio

    2011-01-01

    The G/BBB syndrome is a rare condition characterized by hypertelorism, cleft lip and palate, and hypospadias. No studies were found on the hearing of individuals with this syndrome. To investigate the auditory function in patients with G/BBB syndrome, such as the occurrence of hearing loss, and central and peripheral auditory nerve conduction. Fourteen male patients aged 7-34 years with the G/BBB syndrome were assessed by otoscopy, audiometry, tympanometry and evoked auditory brainstem response (ABR). A retrospective clinical series study. Audiometric thresholds were normal in 12 (66.7%) of the sample and altered in two (33.3%), one with conductive and one with sensorineural loss. ABR results were: all patients had normal absolute wave I latencies; absolute wave III and V latencies were increased in two and six patients, respectively; interpeak latencies I-III, IV and V interpeak latencies were increased in four, three and eight patients respectively. Hearing loss can occur in the G/BBB syndrome. There is evidence of central auditory pathway involvement in the brainstem. Imaging studies are needed to clarify the clinical findings.

  9. Brain stem evoked response audiometry of former drug users.

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    Weich, Tainara Milbradt; Tochetto, Tania Maria; Seligman, Lilian

    2012-10-01

    Illicit drugs are known for their deleterious effects upon the central nervous system and more specifically for how they adversely affect hearing. This study aims to analyze and compare the hearing complaints and the results of brainstem evoked response audiometry (BERA) of former drug user support group goers. This is a cross-sectional non-experimental descriptive quantitative study. The sample consisted of 17 subjects divided by their preferred drug of use. Ten individuals were placed in the marijuana group (G1) and seven in the crack/cocaine group (G2). The subjects were further divided based on how long they had been using drugs: 1 to 5 years, 6 to 10 years, and over 15 years. They were interviewed, and assessed by pure tone audiometry, acoustic impedance tests, and BERA. No statistically significant differences were found between G1 and G2 or time of drug use in absolute latencies and interpeak intervals. However, only five of the 17 individuals had BERA results with adequate results for their ages. Marijuana and crack/cocaine may cause diffuse disorders in the brainstem and compromise the transmission of auditory stimuli regardless of how long these substances are used for.

  10. Nanofibrous scaffolds for the guidance of stem cell-derived neurons for auditory nerve regeneration.

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    Sandra Hackelberg

    Full Text Available Impairment of spiral ganglion neurons (SGNs of the auditory nerve is a major cause for hearing loss occurring independently or in addition to sensory hair cell damage. Unfortunately, mammalian SGNs lack the potential for autonomous regeneration. Stem cell based therapy is a promising approach for auditory nerve regeneration, but proper integration of exogenous cells into the auditory circuit remains a fundamental challenge. Here, we present novel nanofibrous scaffolds designed to guide the integration of human stem cell-derived neurons in the internal auditory meatus (IAM, the foramen allowing passage of the spiral ganglion to the auditory brainstem. Human embryonic stem cells (hESC were differentiated into neural precursor cells (NPCs and seeded onto aligned nanofiber mats. The NPCs terminally differentiated into glutamatergic neurons with high efficiency, and neurite projections aligned with nanofibers in vitro. Scaffolds were assembled by seeding GFP-labeled NPCs on nanofibers integrated in a polymer sheath. Biocompatibility and functionality of the NPC-seeded scaffolds were evaluated in vivo in deafened guinea pigs (Cavia porcellus. To this end, we established an ouabain-based deafening procedure that depleted an average 72% of SGNs from apex to base of the cochleae and caused profound hearing loss. Further, we developed a surgical procedure to implant seeded scaffolds directly into the guinea pig IAM. No evidence of an inflammatory response was observed, but post-surgery tissue repair appeared to be facilitated by infiltrating Schwann cells. While NPC survival was found to be poor, both subjects implanted with NPC-seeded and cell-free control scaffolds showed partial recovery of electrically-evoked auditory brainstem thresholds. Thus, while future studies must address cell survival, nanofibrous scaffolds pose a promising strategy for auditory nerve regeneration.

  11. BioMARK as electrophysiological tool for assessing children at risk for (central) auditory processing disorders without reading deficits.

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    Kumar, Prawin; Singh, Niraj Kumar

    2015-06-01

    Biological Marker of auditory processing (BioMARK) is an electrophysiological test tool widely known as Speech-evoked ABR. Several previous investigations have shown the utility of speech-evoked ABR in the diagnosis of language based processing deficits like learning disability and specific language impairment; however missing from literature is a study that has ruled out the existence of comorbidity of such conditions and carefully delineated the efficacy of speech-evoked ABR in children with children with auditory processing disorders sans reading deficits. Hence, the present study aimed at investigating Speech-evoked ABR in children with auditory processing disorders without reading problems. A total of 336 school going children in the age range of 8-12 years were screened for presence of central auditory processing deficits. Among the 51 children who were identified as at risk, 15 were randomly selected and served as experimental group. The control group comprised of fifteen age matched children. The inter-group comparison was done using MANOVA, which revealed significant prolongations of latencies of waves V and A (p = 0.001) along with marginal reductions in V/A slope (p = 0.052) and amplitude of responses to first formant (p = 0.065). The responses to higher frequencies did not differ between the groups. Speech-evoked ABR are affected in children who are at risk of central auditory processing disorders sans reading deficits which probably indicates the presence of abnormal brainstem encoding of speech signal in this population. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Potencial evocado auditivo tardio relacionado a eventos (P300 na síndrome de Down Late auditory event-related evoked potential (P300 in Down's syndrome patients

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    Carla Patrícia Hernandez Alves Ribeiro César

    2010-04-01

    Full Text Available A síndrome de Down é causada pela trissomia do cromossomo 21 e está associada com alteração do processamento auditivo, distúrbio de aprendizagem e, provavelmente, início precoce de Doença de Alzheimer. OBJETIVO: Avaliar as latências e amplitudes do potencial evocado auditivo tardio relacionado a eventos (P300 e suas alterações em indivíduos jovens adultos com síndrome de Down. MATERIAL E MÉTODO: Estudo de caso prospectivo. Latências e amplitudes do P300 foram avaliadas em 17 indivíduos com síndrome de Down e 34 indivíduos sadios. RESULTADOS: Foram identificadas latências do P300 (N1, P2, N2 e P3 prolongadas e amplitude N2 - P3 diminuída nos indivíduos com síndrome de Down quando comparados ao grupo controle. CONCLUSÃO: Em indivíduos jovens adultos com síndrome de Down ocorre aumento das latências N1, P2, N2 e P3, e diminuição significativa da amplitude N2-P3 do potencial evocado auditivo tardio relacionado a eventos (P300, sugerindo prejuízo da integração da área de associação auditiva com as áreas corticais e subcorticais do sistema nervoso central.Down syndrome is caused by a trisomy of chromosome 21 and is associated with central auditory processing deficit, learning disability and, probably, early-onset Alzheimer's disease. AIM: to evaluate the latencies and amplitudes of evoked late auditory potential related to P300 events and their changes in young adults with Down's syndrome. MATERIALS AND METHODS: Prospective case study. P300 test latency and amplitudes were evaluated in 17 individuals with Down's syndrome and 34 healthy individuals. RESULTS The P300 latency (N1, P2, N2 and P3 was longer and the N2-P3 amplitude was lower in individuals with Down syndrome when compared to those in the control group. CONCLUSION: In young adults with Down syndrome, N1, P2, N2 and P3 latencies of late auditory evoked potential related to P300 events were prolonged, and N2 - P3 amplitudes were significantly reduced

  13. The Effect of Neonatal Hyperbilirubinemia on the Auditory System

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    Dr. Zahra Jafari

    2008-12-01

    Full Text Available Background and Aim: Hyperbilirubinemia during the neonatal period is known to be an important risk factor for neonatal auditory impairment, and may reveal as a permanent brain damage, if no proper therapeutic intervention is considered. In the present study some electroacoustic and electrophysiologic tests were used to evaluate function of auditory system in a group of children with severe neonatal Jaundice. Materials and Methods: Forty five children with mean age of 16.1 14.81 months and 17 mg/dl and higher bilirubin level were studied, and the transient evoked otoacoustic emission, acoustic reflex, auditory brainstem response and auditory steady-state response tests were performed for them. Results: The mean score of bilirubin was 29.37 8.95 mg/dl. It was lower than 20 mg/dl in 22.2%, between 20-30 mg/dl in 24.4% and more than 30 mg/dl in 48.0% of children. No therapeutic intervention in 26.7%, phototherapy in 44.4%, and blood exchange in 28.9% of children were reported. 48.9% hypoxia and 26.6% preterm birth history was shown too. TEOAEs was recordable in 71.1% of cases. The normal result in acoustic reflex, ABR and ASSR tests was shown just in 11.1% of cases. The clinical symptoms of auditory neuropathy were revealed in 57.7% of children. Conclusion: Conducting auditory tests sensitive to hyperbilirubinemia place of injury is necessary to inform from functional effect and severity of disorder. Because the auditory neuropathy/ dys-synchrony is common in neonates with hyperbilirubinemic, the OAEs and ABR are the minimum essential tests to identify this disorder.

  14. Brainstem Cavernous Angioma

    Science.gov (United States)

    ... in obliteration of the angioma. [9] At a minimum, radiosurgery treatment for brainstem cavernous angioma is controversial. Given the advancement in minimally invasive surgical techniques, more and more neurosurgeons are becoming ...

  15. Effects of Noise Exposure on the Auditory Function of Ovariectomized Rats with Estrogen Deficiency.

    Science.gov (United States)

    Hu, Xujun; Wang, Ying; Lau, Chi Chuen

    2016-12-01

    The benefits of estrogen for the auditory function of women depend on a number of factors. In this study, we aimed to examine the impact of noise trauma on the auditory function of ovariectomized rats with estrogen deficiency. Twenty-eight young, female Sprague-Dawley rats were assigned to three groups (OVX+N, OVX-N, Sham+N). Rats in the OVX+N group and the OVX-N group underwent bilateral ovariectomy (OVX); the OVX+N group alone was also exposed to white noise (N) of 115 dB SPL for 8 hours a day over 14 days. The Sham+N group consisted of rats with intact ovaries that were exposed to the same noise. The auditory function of all rats was measured before treatment and after noise exposure by the signal-to-noise ratio (SNR) of distortion-product otoacoustic emissions (DPOAE) and the threshold of auditory-evoked brainstem response (ABR). The Sham+N group (intact ovaries, noise-exposed) had worse auditory function than the OVX-N group (ovariectomy, no noise). The OVX+N group had decreased SNRs of DPOAE and increased ABR thresholds relative to the Sham+N group. Noise exposure may cause greater damage to auditory function when estrogen levels are low in females.

  16. Abnormalities in auditory evoked potentials of 75 patients with Arnold-Chiari malformations types I and II Anormalidades nos potenciais evocados auditivos de 75 pacientes com os tipos I e II das malformações de Arnold-Chiari

    Directory of Open Access Journals (Sweden)

    Paulo Sergio A. Henriques Filho

    2006-09-01

    Full Text Available OBJECTIVE: To evaluate the frequency and degree of severity of abnormalities in the auditory pathways in patients with Chiari malformations type I and II. METHOD: This is a series-of-case descriptive study in which the possible presence of auditory pathways abnormalities in 75 patients (48 children and 27 adults with Chiari malformation types I and II were analyzed by means of auditory evoked potentials evaluation. The analysis was based on the determination of intervals among potentials peak values, absolute latency and amplitude ratio among potentials V and I. RESULTS: Among the 75 patients studied, 27 (36% disclosed Arnold-Chiari malformations type I and 48 (64% showed Arnold-Chiari malformations type II. Fifty-three (71% of these patients showed some degree of auditory evoked potential abnormalities. Tests were normal in the remaining 22 (29% patients. CONCLUSION: Auditory evoked potentials testing can be considered a valuable instrument for diagnosis and evaluation of brain stem functional abnormalities in patients with Arnold-Chiari malformations type I and II. The determination of the presence and degree of severity of these abnormalities can be contributory to the prevention of further handicaps in these patients either through physical therapy or by means of precocious corrective surgical intervention.OBJETIVO: Avaliar a freqüência e grau de comprometimento das vias auditivas em tronco cerebral por meio de potencial evocado auditivo, em pacientes afetados por malformações de Arnold-Chiari de tipos I e II. MÉTODO: Foi efetuado um estudo descritivo de tipo série de casos, sendo selecionados 75 pacientes (48 crianças e 27 adultos nos quais foi realizada avaliação dos potenciais evocados das vias auditivas, com base à determinação dos valores dos intervalos entre picos de potenciais, da latência absoluta e da razão entre as amplitudes dos potenciais V e I. RESULTADOS: Entre os 75 pacientes avaliados, 27 (36% apresentavam

  17. Auditory Evoked Potentials for the Evaluation of Hearing Sensitivity in Navy Dolphins. Modification P00002: Assessment of Hearing Sensitivity in Adult Male Elephant Seals

    Science.gov (United States)

    2006-12-30

    is likely frequency dependent. electrical leakage to the water. Differences between the in-air The limitations in the jawphone calibration mean that...method provides noticeable gains given the vari- moto , M., Sato, 0., Suga, N., and Yanagisawa, K. (1968). "Electrophysi- ability inherent in evoked...underwater (seawater provides an alternative dress a need for periodic hearing assessment of dolphins at low resistance path for the electrical

  18. An evoked auditory response fMRI study of the effects of rTMS on putative AVH pathways in healthy volunteers.

    LENUS (Irish Health Repository)

    Tracy, D K

    2010-01-01

    Auditory verbal hallucinations (AVH) are the most prevalent symptom in schizophrenia. They are associated with increased activation within the temporoparietal cortices and are refractory to pharmacological and psychological treatment in approximately 25% of patients. Low frequency repetitive transcranial magnetic stimulation (rTMS) over the temporoparietal cortex has been demonstrated to be effective in reducing AVH in some patients, although results have varied. The cortical mechanism by which rTMS exerts its effects remain unknown, although data from the motor system is suggestive of a local cortical inhibitory effect. We explored neuroimaging differences in healthy volunteers between application of a clinically utilized rTMS protocol and a sham rTMS equivalent when undertaking a prosodic auditory task.

  19. Auditory neuropathy/Auditory dyssynchrony - An underdiagnosed condition: A case report with review of literature

    OpenAIRE

    Vinish Agarwal; Saurabh Varshney; Sampan Singh Bist; Sanjiv Bhagat; Sarita Mishra; Vivek Jha

    2012-01-01

    Auditory neuropathy (AN)/auditory dyssynchrony (AD) is a very often missed diagnosis, hence an underdiagnosed condition in clinical practice. Auditory neuropathy is a condition in which patients, on audiologic evaluation, are found to have normal outer hair cell function and abnormal neural function at the level of the eighth nerve. These patients, on clinical testing, are found to have normal otoacoustic emissions, whereas auditory brainstem response audiometry reveals the absence of neural ...

  20. The correlation between central auditory processing in autistic children and their language processing abilities.

    Science.gov (United States)

    Azouz, Hanan Galal; Kozou, Hesham; Khalil, Mona; Abdou, Rania M; Sakr, Mohamed

    2014-12-01

    To study the auditory profile at different levels of the auditory system in children with ASD and to verify the role of (Central) auditory processing disorder as an essential pathology of the autistic disorder or as an associated co-morbidity, and to establish the correlation between CAP findings and the language delay in these cases. The study included 30 children with definite autistic disorder according to DSM-IV-TR criteria and ADI-R among those attending the outpatient neuropsychiatry clinic of Alexandria University Children Hospital at El Shatby. An informed consent was taken from all patients in this part of the study. Confidentiality of the records was maintained. All cases were subjected to complete history taking and examination; special assessment to language skills and evoked potentials were done. The results concluded that (central) auditory processing disorder is an essential pathology of the autistic disorder. Autistic children possess a dysfunctioning or an immature central auditory nervous system at both the brainstem and cortical levels. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. Short-wavelength infrared laser activates the auditory neurons: comparing the effect of 980 vs. 810 nm wavelength.

    Science.gov (United States)

    Tian, Lan; Wang, Jingxuan; Wei, Ying; Lu, Jianren; Xu, Anting; Xia, Ming

    2017-02-01

    Research on auditory neural triggering by optical stimulus has been developed as an emerging technique to elicit the auditory neural response, which may provide an alternative method to the cochlear implants. However, most previous studies have been focused on using longer-wavelength near-infrared (>1800 nm) laser. The effect comparison of different laser wavelengths in short-wavelength infrared (SWIR) range on the auditory neural stimulation has not been previously explored. In this study, the pulsed 980- and 810-nm SWIR lasers were applied as optical stimuli to irradiate the auditory neurons in the cochlea of five deafened guinea pigs and the neural response under the two laser wavelengths was compared by recording the evoked optical auditory brainstem responses (OABRs). In addition, the effect of radiant exposure, laser pulse width, and threshold with the two laser wavelengths was further investigated and compared. The one-way analysis of variance (ANOVA) was used to analyze those data. Results showed that the OABR amplitude with the 980-nm laser is higher than the amplitude with the 810-nm laser under the same radiant exposure from 10 to 102 mJ/cm(2). And the laser stimulation of 980 nm wavelength has lower threshold radiant exposure than the 810 nm wavelength at varied pulse duration in 20-500 μs range. Moreover, the 810-nm laser has a wider optimized pulse duration range than the 980-nm laser for the auditory neural stimulation.

  2. A brainstem anosognosia of hemiparesis

    Directory of Open Access Journals (Sweden)

    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.

  3. Sound detection by the longfin squid (Loligo pealeii) studied with auditory evoked potentials: sensitivity to low-frequency particle motion and not pressure

    DEFF Research Database (Denmark)

    Mooney, T. Aran; Hanlon, Roger T; Christensen-Dalsgaard, Jakob

    2010-01-01

    Although hearing has been described for many underwater species, there is much debate regarding if and how cephalopods detect sound. Here we quantify the acoustic sensitivity of the longfin squid (Loligo pealeii) using near-field acoustic and shaker-generated acceleration stimuli. Sound field...... of two wave types: (1) rapid stimulus-following waves, and (2) slower, high-amplitude waves, similar to some fish AEPs. Responses were obtained between 30 and 500 Hz with lowest thresholds between 100 and 200 Hz. At the best frequencies, AEP amplitudes were often >20 µV. Evoked potentials were...... extinguished at all frequencies if (1) water temperatures were less than 8°C, (2) statocysts were ablated, or (3) recording electrodes were placed in locations other than near the statocysts. Both the AEP response characteristics and the range of responses suggest that squid detect sound similarly to most fish...

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

    Science.gov (United States)

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

    2017-01-01

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

  5. Functional imaging of the human brainstem during somatosensory input and autonomic output

    Directory of Open Access Journals (Sweden)

    Luke Anthony Henderson

    2013-09-01

    Full Text Available Over the past half a century, many experimental animal investigations have explored the role of various brainstem regions in a variety of conditions. Despite the accumulation of a considerable body of knowledge in primarily anaesthetized preparations, relatively few investigations have explored brainstem function in awake humans. It is important that human brainstem function is explored given that many neurological conditions, from obstructive sleep apnea, chronic pain and hypertension, likely involve significant changes in the processing of information within the brainstem. Recent advances in the collection and processing of magnetic resonance images, has resulted in the possibility of exploring brainstem activity changes in awake healthy individuals and in those with various clinical conditions. We and others have begun to explore changes in brainstem activity in humans during a number of challenges, including during cutaneous and muscle pain, as well as during challenges that evoke increases in sympathetic activity. More recently we have successfully recorded sympathetic nerve activity concurrently with fMRI of the brainstem, which will allow us, for the first time to explore brainstem sites directly responsible for conditions such as hypertension. Since many conditions will involve changes in brainstem function and structure, defining brainstem changes will likely result in a greater ability to develop more effective treatment regimes.

  6. Síndrome da apneia obstrutiva do sono e o potencial auditivo P300 Obstructive sleep apnea and P300 evoked auditory potential

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Martins

    2011-12-01

    Full Text Available A Síndrome da Apneia Obstrutiva do Sono (SAOS diminui as capacidades da atenção, memória e concentração, fatores relacionados com a cognição. A análise dos parâmetros do P300 auditivo permitiria inferir disfunção cognitiva. OBJETIVO: Comparar os dados da polissonografia e do P300 auditivo em adultos, roncopatas primários com portadores de SAOS. CASUÍSTICA E MÉTODO: Estudo prospectivo em roncopatas primários (N=12 e em portadores de SAOS (N=54, submetidos à polissonografia definidos pelo índice de apneia e hipopneia (IAH. As variáveis da polissonografia e as do P300 foram comparadas, pelos testes "T" de Student, exato de Fisher, regressão logística e análise de correlação com nível de significância de 5%. RESULTADOS: O IAH apresentou correlação inversa com a oximetria em ambos os grupos. A prevalência do P300 foi menor no G.SAOS (teste exato de Fisher, p=0,027. A idade dos pacientes não influenciou a prevalência do P300 (análise de regressão; p=0,232. A amplitude do P300 foi menor do G.SAOS (teste "T" de Student; p=0,003 a latência do P300 foi semelhante em ambos os grupos (teste "T" de Student; p=0,89. CONCLUSÃO: A redução da amplitude do P300 nos portadores de SAOS sugere disfunção cognitiva induzida por diminuição da memória auditiva.The obstructive sleep apnea syndrome (OSAS reduces attention span, memory and concentration capacities, all associated with cognition. The analysis of the auditory P300 parameters could help infer cognitive dysfunction. OBJECTIVE: To compare the data from polysomnography and the auditory P300 in adults, primary snorers with OSAS patients. MATERIALS AND METHODS: Prospective study with primary snorers (N=12 and in OSAS patients (N=54, submitted to polysomnography, defined by the apnea-hypopnea index (AHI. The polysomnography and P300 variables were compared by the t-Student test, the Exact Fisher's Test, logistic regression and analysis of correlation with a significance

  7. Effects of Age and Degree of Hearing Loss on the Agreement and Correlation Between Sound Field Audiometric Thresholds and Tone Burst Auditory Brainstem Response Thresholds in Infants and Young Children

    Directory of Open Access Journals (Sweden)

    Chung-Yi Lee

    2008-11-01

    Conclusion: The evoked-potentials test, properly obtained and interpreted with respect to the effects of age and degree of hearing loss, may provide a very informative hearing threshold reference to help in behavioral audiometric evaluation in infants and young children with hearing loss.

  8. Potenciales evocados auditivos del tallo cerebral en monos rhesus (Macaca mulatta) en diferentes etapas fisiológicas en condiciones de cautiverio Brainstem's auditory evoked potentials in rhesus monkeys (Macaca mulatta) in different physiologic stages under captivity

    OpenAIRE

    A Ibáñez-Contreras; A Durand-Rivera; B Hernández-Godínez; S Reyes-Pantoja

    2011-01-01

    La audición juega un papel importante en el desarrollo de conductas más elaboradas en los organismos a medida en que se asciende en la escala filogenética. El objetivo de este estudio fue evaluar la respuesta de la vía auditiva en la especie Macaca mulatta, en diferentes etapas fisiológicas, a través de los Potenciales Evocados Auditivos del Tallo Cerebral (PEATC). Se utilizaron 30 primates no humanos de la especie Macaca mulatta divididos en dos grupos de 15 machos y 15 hembras. Cada grupo e...

  9. Corticosteroid therapy in regressive autism: a retrospective study of effects on the Frequency Modulated Auditory Evoked Response (FMAER), language, and behavior.

    Science.gov (United States)

    Duffy, Frank H; Shankardass, Aditi; McAnulty, Gloria B; Eksioglu, Yaman Z; Coulter, David; Rotenberg, Alexander; Als, Heidelise

    2014-05-15

    Up to a third of children with Autism Spectrum Disorder (ASD) manifest regressive autism (R-ASD).They show normal early development followed by loss of language and social skills. Absent evidence-based therapies, anecdotal evidence suggests improvement following use of corticosteroids. This study examined the effects of corticosteroids for R-ASD children upon the 4 Hz frequency modulated evoked response (FMAER) arising from language cortex of the superior temporal gyrus (STG) and upon EEG background activity, language, and behavior. An untreated clinical convenience sample of ASD children served as control sample. Twenty steroid-treated R-ASD (STAR) and 24 not-treated ASD patients (NSA), aged 3 - 5 years, were retrospectively identified from a large database. All study participants had two sequential FMAER and EEG studies;Landau-Kleffner syndrome diagnosis was excluded. All subjects' records contained clinical receptive and expressive language ratings based upon a priori developed metrics. The STAR group additionally was scored behaviorally regarding symptom severity as based on the Diagnostic and Statistical Manual IV (DSM-IV) ASD criteria list. EEGs were visually scored for abnormalities. FMAER responses were assessed quantitatively by spectral analysis. Treated and untreated group means and standard deviations for the FMAER, EEG, language, and behavior, were compared by paired t-test and Fisher's exact tests. The STAR group showed a significant increase in the 4 Hz FMAER spectral response and a significant reduction in response distortion compared to the NSA group. Star group subjects' language ratings were significantly improved and more STAR than NSA group subjects showed significant language improvement. Most STAR group children showed significant behavioral improvement after treatment. STAR group language and behavior improvement was retained one year after treatment. Groups did not differ in terms of minor EEG abnormalities. Steroid treatment produced no

  10. The Reduced Cochlear Output and the Failure to Adapt the Central Auditory Response Causes Tinnitus in Noise Exposed Rats

    Science.gov (United States)

    Matsumoto, Masahiro; Lee, Sze Chim; Zuccotti, Annalisa; Zimmermann, Ulrike; Jaumann, Mirko; Rohbock, Karin; Xiong, Hao; Knipper, Marlies

    2013-01-01

    Tinnitus is proposed to be caused by decreased central input from the cochlea, followed by increased spontaneous and evoked subcortical activity that is interpreted as compensation for increased responsiveness of central auditory circuits. We compared equally noise exposed rats separated into groups with and without tinnitus for differences in brain responsiveness relative to the degree of deafferentation in the periphery. We analyzed (1) the number of CtBP2/RIBEYE-positive particles in ribbon synapses of the inner hair cell (IHC) as a measure for deafferentation; (2) the fine structure of the amplitudes of auditory brainstem responses (ABR) reflecting differences in sound responses following decreased auditory nerve activity and (3) the expression of the activity-regulated gene Arc in the auditory cortex (AC) to identify long-lasting central activity following sensory deprivation. Following moderate trauma, 30% of animals exhibited tinnitus, similar to the tinnitus prevalence among hearing impaired humans. Although both tinnitus and no-tinnitus animals exhibited a reduced ABR wave I amplitude (generated by primary auditory nerve fibers