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Patel TR, Shahin AJ, Bhat J, Welling DB, Moberly AC. Cortical Auditory Evoked Potentials to Evaluate Cochlear Implant Candidacy in an Ear With Long-standing Hearing Loss: A Case Report. Ann Otol Rhinol Laryngol 2016; 125:858-61. [PMID: 27357975 DOI: 10.1177/0003489416656647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES We describe a novel use of cortical auditory evoked potentials in the preoperative workup to determine ear candidacy for cochlear implantation. METHODS A 71-year-old male was evaluated who had a long-deafened right ear, had never worn a hearing aid in that ear, and relied heavily on use of a left-sided hearing aid. Electroencephalographic testing was performed using free field auditory stimulation of each ear independently with pure tones at 1000 and 2000 Hz at approximately 10 dB above pure-tone thresholds for each frequency and for each ear. RESULTS Mature cortical potentials were identified through auditory stimulation of the long-deafened ear. The patient underwent successful implantation of that ear. He experienced progressively improving aided pure-tone thresholds and binaural speech recognition benefit (AzBio score of 74%). CONCLUSIONS Findings suggest that use of cortical auditory evoked potentials may serve a preoperative role in ear selection prior to cochlear implantation.
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Affiliation(s)
- Tirth R Patel
- The Ohio State University, Wexner Medical Center, Columbus, Ohio, USA
| | - Antoine J Shahin
- University of California Davis, Center for Mind and Brain, Davis, California, USA
| | - Jyoti Bhat
- The Ohio State University, Wexner Medical Center, Columbus, Ohio, USA
| | | | - Aaron C Moberly
- The Ohio State University, Wexner Medical Center, Columbus, Ohio, USA
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Boisvert I, McMahon CM, Dowell RC, Lyxell B. Long-term asymmetric hearing affects cochlear implantation outcomes differently in adults with pre- and postlingual hearing loss. PLoS One 2015; 10:e0129167. [PMID: 26043227 PMCID: PMC4456415 DOI: 10.1371/journal.pone.0129167] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Accepted: 05/05/2015] [Indexed: 02/01/2023] Open
Abstract
In many countries, a single cochlear implant is offered as a treatment for a bilateral hearing loss. In cases where there is asymmetry in the amount of sound deprivation between the ears, there is a dilemma in choosing which ear should be implanted. In many clinics, the choice of ear has been guided by an assumption that the reorganisation of the auditory pathways caused by longer duration of deafness in one ear is associated with poorer implantation outcomes for that ear. This assumption, however, is mainly derived from studies of early childhood deafness. This study compared outcomes following implantation of the better or poorer ear in cases of long-term hearing asymmetries. Audiological records of 146 adults with bilateral hearing loss using a single hearing aid were reviewed. The unaided ear had 15 to 72 years of unaided severe to profound hearing loss before unilateral cochlear implantation. 98 received the implant in their long-term sound-deprived ear. A multiple regression analysis was conducted to assess the relative contribution of potential predictors to speech recognition performance after implantation. Duration of bilateral significant hearing loss and the presence of a prelingual hearing loss explained the majority of variance in speech recognition performance following cochlear implantation. For participants with postlingual hearing loss, similar outcomes were obtained by implanting either ear. With prelingual hearing loss, poorer outcomes were obtained when implanting the long-term sound-deprived ear, but the duration of the sound deprivation in the implanted ear did not reliably predict outcomes. Contrary to an apparent clinical consensus, duration of sound deprivation in one ear has limited value in predicting speech recognition outcomes of cochlear implantation in that ear. Outcomes of cochlear implantation are more closely related to the period of time for which the brain is deprived of auditory stimulation from both ears.
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Affiliation(s)
- Isabelle Boisvert
- Department Linguistics, Macquarie University, Sydney, New South Wales, Australia
- HEARing Cooperative Research Centre, Melbourne, Victoria, Australia
- SCIC Cochlear Implant Program - An RIDBC service, Sydney, New South Wales, Australia
- Linnaeus Centre HEAD, The Swedish Institute for Disability Research, Linköping, Sweden
- * E-mail:
| | - Catherine M. McMahon
- Department Linguistics, Macquarie University, Sydney, New South Wales, Australia
- HEARing Cooperative Research Centre, Melbourne, Victoria, Australia
| | - Richard C. Dowell
- HEARing Cooperative Research Centre, Melbourne, Victoria, Australia
- Department of Audiology and Speech Pathology, The University of Melbourne, Melbourne, Victoria, Australia
- Audiology, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Björn Lyxell
- Department of Behavioural Sciences and Learning, Linköping University, Linköping, Sweden
- Linnaeus Centre HEAD, The Swedish Institute for Disability Research, Linköping, Sweden
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McNeill C, Noble W, Purdy SC, O'Brien A, Sharma M. Bilateral cochlear implants in long-term and short-term deafness. Cochlear Implants Int 2013; 13:50-3. [DOI: 10.1179/146701011x13061407457704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Alvarenga KF, Amorim RB, Agostinho-Pesse RS, Costa OA, Nascimento LT, Bevilacqua MC. Speech perception and cortical auditory evoked potentials in cochlear implant users with auditory neuropathy spectrum disorders. Int J Pediatr Otorhinolaryngol 2012; 76:1332-8. [PMID: 22796193 DOI: 10.1016/j.ijporl.2012.06.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 05/29/2012] [Accepted: 06/03/2012] [Indexed: 10/28/2022]
Abstract
OBJECTIVE To characterize the P(1) component of long latency auditory evoked potentials (LLAEPs) in cochlear implant users with auditory neuropathy spectrum disorder (ANSD) and determine firstly whether they correlate with speech perception performance and secondly whether they correlate with other variables related to cochlear implant use. METHODS This study was conducted at the Center for Audiological Research at the University of São Paulo. The sample included 14 pediatric (4-11 years of age) cochlear implant users with ANSD, of both sexes, with profound prelingual hearing loss. Patients with hypoplasia or agenesis of the auditory nerve were excluded from the study. LLAEPs produced in response to speech stimuli were recorded using a Smart EP USB Jr. system. The subjects' speech perception was evaluated using tests 5 and 6 of the Glendonald Auditory Screening Procedure (GASP). RESULTS The P(1) component was detected in 12/14 (85.7%) children with ANSD. Latency of the P(1) component correlated with duration of sensorial hearing deprivation (*p=0.007, r=0.7278), but not with duration of cochlear implant use. An analysis of groups assigned according to GASP performance (k-means clustering) revealed that aspects of prior central auditory system development reflected in the P(1) component are related to behavioral auditory skills. CONCLUSIONS In children with ANSD using cochlear implants, the P(1) component can serve as a marker of central auditory cortical development and a predictor of the implanted child's speech perception performance.
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Affiliation(s)
- Kátia F Alvarenga
- Department of Audiology and Speech Pathology at the School of Dentistry, University of São Paulo, Bauru Campus, Brazil.
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Hari R, Salmelin R. Magnetoencephalography: From SQUIDs to neuroscience. Neuroimage 20th anniversary special edition. Neuroimage 2011; 61:386-96. [PMID: 22166794 DOI: 10.1016/j.neuroimage.2011.11.074] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 11/03/2011] [Accepted: 11/25/2011] [Indexed: 10/14/2022] Open
Abstract
Magnetoencephalography (MEG), with its direct view to the cortex through the magnetically transparent skull, has developed from its conception in physics laboratories to a powerful tool of basic and clinical neuroscience. MEG provides millisecond time resolution and allows real-time tracking of brain activation sequences during sensory processing, motor planning and action, cognition, language perception and production, social interaction, and various brain disorders. Current-day neuromagnetometers house hundreds of SQUIDs, superconducting quantum interference devices, to pick up signals generated by concerted action of cortical neurons. Complementary MEG measures of neuronal involvement include evoked responses, modulation of cortical rhythms, properties of the on-going neural activity, and interareal connectivity. Future MEG breakthroughs in understanding brain dynamics are expected through advanced signal analysis and combined use of MEG with hemodynamic imaging (fMRI). Methodological development progresses most efficiently when linked with insightful neuroscientific questions.
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Affiliation(s)
- Riitta Hari
- Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto University School of Science, Espoo, Finland.
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Pitfalls in the management of monaural deafness. The Journal of Laryngology & Otology 2011; 125:741-4. [PMID: 21693077 DOI: 10.1017/s0022215111000934] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE We report a patient who underwent cochlear implantation in an ear with long-term deafness, after an acoustic neuroma had been removed surgically from the other, hitherto good ear and the cochlear nerve had subsequently been resected to relieve severe tinnitus. METHOD Case report. RESULTS The patient could not tolerate the cochlear implant, because of a moderate headache due to the stimulation level necessary for environmental sound discrimination. CONCLUSION Cochlear implantation in patients with long-term deafness should be considered carefully, even if deafness is monaural.
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Musiek FE, Daniels SB. Central auditory mechanisms associated with cochlear implantation: an overview of selected studies and comment. Cochlear Implants Int 2010; 11 Suppl 1:15-28. [PMID: 21756581 DOI: 10.1179/146701010x12671178390753] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Recently, the evaluation of the role of the central auditory system in the utilization of cochlear implants has received much attention. In order to fully understand the results of cochlear implantation, one must have an understanding of how the brain is influenced by electrical stimulation of the auditory nerve. This review provides an overview of the structure and function of the central auditory nervous system and the changes that occur as a result of cochlear implant use. Evidence of central auditory plasticity is discussed highlighting key imaging and evoked potential studies.
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Affiliation(s)
- Frank E Musiek
- Department of Communication Sciences, Neuroaudiology Lab, University of Connecticut, Storrs, CT 06269, USA.
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McNeill C, Sharma M, Purdy SC, Agung K. Cortical auditory evoked responses from an implanted ear after 50 years of profound unilateral deafness. Cochlear Implants Int 2008; 8:189-99. [PMID: 18033739 DOI: 10.1179/cim.2007.8.4.189] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
A male with unilateral deafness in the right ear since 8 years of age developed a sudden hearing loss in the left ear at age 63. A hearing aid was fitted in the left ear with limited benefit. The right ear received a cochlear implant (CI) 20 months later. Cortical auditory evoked potentials (CAEPs) and speech recognition scores (SRS) were measured in free-field three, six and nine months after implantation with the hearing aid alone, CI alone and bimodal condition (hearing aid and CI together). Three months after implantation the cortical responses for the two ears were similar, despite more than 50 years of unilateral auditory deprivation. CAEPs measured over time show evidence of binaural interaction and improvements in SRS.
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Kelly AS, Purdy SC, Thorne PR. Electrophysiological and speech perception measures of auditory processing in experienced adult cochlear implant users. Clin Neurophysiol 2005; 116:1235-46. [PMID: 15978485 DOI: 10.1016/j.clinph.2005.02.011] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2003] [Revised: 01/31/2005] [Accepted: 02/14/2005] [Indexed: 11/20/2022]
Abstract
OBJECTIVE This study determined the relationship between auditory evoked potential measures and speech perception in experienced adult cochlear implant (CI) users and compared the CI evoked potential results to those of a group of age- and sex-matched control subjects. METHODS CI subjects all used the Nucleus CI-22 implant. Middle latency response (MLR), obligatory cortical potentials (CAEP), mismatch negativity (MMN) and P3a auditory evoked potentials were recorded. Speech perception was evaluated using word and sentence tests. RESULTS Duration of deafness correlated with speech scores with poor scores reflecting greater years of deafness. Na amplitude correlated negatively with duration of deafness, with small amplitudes reflecting greater duration of deafness. Overall, N1 amplitude was smaller in CI than control subjects. Earlier P2 latencies were associated with shorter durations of deafness and higher speech scores. In general, MMN was absent or degraded in CI subjects with poor speech scores. CONCLUSIONS Auditory evoked potentials are related to speech perception ability and provide objective evidence of central auditory processing differences across experienced CI users. SIGNIFICANCE Since auditory evoked potentials relate to CI performance, they may be a useful tool for objectively evaluating the efficacy of speech processing strategies and/or auditory training approaches in both adults and children with cochlear implants.
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Affiliation(s)
- Andrea S Kelly
- Discipline of Audiology, The University of Auckland, Private Bag 92-019, Auckland, New Zealand.
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Kühn-Inacker H, Shehata-Dieler W, Müller J, Helms J. Bilateral cochlear implants: a way to optimize auditory perception abilities in deaf children? Int J Pediatr Otorhinolaryngol 2004; 68:1257-66. [PMID: 15364496 DOI: 10.1016/j.ijporl.2004.04.029] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2003] [Revised: 04/23/2004] [Accepted: 04/27/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVES The Würzburg bilateral cochlear implant (CI) program was started with the aim to improve the patients' communicative abilities in complex listening situations. In this study, the auditory skills of children using bilateral cochlear implants were evaluated. STUDY DESIGN AND SETTINGS Qualitative data based on free observations in the rehabilitation setup were collected in 39 bilaterally implanted children. A speech discrimination in noise test was performed in 18 of these children; lists of bisyllabic words were presented in noise at a signal to noise ratio (SNR) of +15 dB. RESULTS Qualitative and quantitative data show clearly that bilateral CI improves the children's communicative behaviour, especially in complex listening situations. Children examined with the speech in noise test scored significantly better under the bilateral condition compared to the unilateral condition. Integration of the second implanted side and use of binaural information was observed to be easier and faster in children with a short time lag between both implants. CONCLUSIONS To be able to obtain optimal benefit from bilateral cochlear implants, an intensive rehabilitation program is necessary. The important aspects of such a program are creating realistic expectations in older children before implantation; performing the first processor fitting of the second side with the first side switched on; and separate intensive training with the new system in order to balance out the hearing competence of the second CI with that of the first.
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Gordon KA, Papsin BC, Harrison RV. Activity-dependent developmental plasticity of the auditory brain stem in children who use cochlear implants. Ear Hear 2004; 24:485-500. [PMID: 14663348 DOI: 10.1097/01.aud.0000100203.65990.d4] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES 1) To determine if a period of early auditory deprivation influences neural activity patterns as revealed by human auditory brain stem potentials evoked by electrical stimulation from a cochlear implant. 2) To examine the potential for plasticity in the human auditory brain stem. Specifically, we asked if electrically evoked auditory potentials from the auditory nerve and brain stem in children show evidence of development as a result of implant use. 3) To assess whether a sensitive or critical period exists in auditory brain stem development. Specifically, is there an age of implantation after which there are no longer developmental changes in auditory brain stem activity as revealed by electrically evoked potentials? DESIGN The electrically evoked compound potential of the auditory nerve (ECAP) and the electrically evoked auditory brain stem response (EABR) were recorded repeatedly during the first year of implant use in each of 50 children. The children all had pre- or peri-lingual onset of severe to profound sensorineural hearing loss and received their implants at ages ranging from 12 mo to 17 yr. All children received Nucleus cochlear implant devices. All children were in therapy and in school programs that emphasized listening and required the children to wear their implants consistently. RESULTS Initial stimulation from the cochlear implant evoked clear responses from the auditory nerve and auditory brain stem in most children. There was no correlation between minimum latency, maximum amplitude, or slope of amplitude growth of initial responses with age at implantation for ECAP eN1, EABR eIII and eV components (p > 0.05). During the first year of implant use, minimum latency of these waves significantly decreased (p < 0.01, p < 0.0001, p < 0.0001, respectively). Neural conduction time, measured using the interwave latency of ECAP eN1-EABR eIII for lower brain stem and EABR eIII-eV for upper brain stem, decreased during the period of 6 to 12 mo of cochlear implant use (p < 0.01 (lower), p < 0.0001(upper)). The ECAP wave eN1 and the EABR wave eV showed significant increases in amplitude during time of implant use (p < 0.05 and p < 0.01, respectively). There were no correlations between the rate of interwave latency decrease and the rate of amplitude increases and the age at which children underwent implantation (p < 0.05). CONCLUSIONS Activity in the auditory pathways to the level of the midbrain can be evoked by acute stimulation from a cochlear implant. EABR measures are not influenced by any period of auditory deprivation. Auditory development proceeds once the implant is activated and involves improvements in neural conduction velocity and neural synchrony. Underlying mechanisms likely include improvements in synaptic efficacy and possibly increased myelination. The developmental plasticity that we have shown in the human auditory brain stem does not appear from EABR data to be limited by a critical period during childhood.
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Affiliation(s)
- Karen A Gordon
- Cochlear Implant Laboratory, Department of Otolaryngology, The Hospital for Sick Children, University of Toronto, Ontario, Canada, M5G 1X8.
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Robinson K. Implications of developmental plasticity for the language acquisition of deaf children with cochlear implants. Int J Pediatr Otorhinolaryngol 1998; 46:71-80. [PMID: 10190707 DOI: 10.1016/s0165-5876(98)00125-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The study of language acquisition in profoundly deaf children with cochlear implants informs us about the developmental plasticity of the auditory system. Sensory activity leads to neural development, and the sustained effects of sensory inactivity can lead to a loss of responsiveness. These effects may be reversed by the subsequent provision of sensory stimulation, such as that delivered by cochlear implants. Behavioral and electrophysiological research on the effects of speech deprivation on language acquisition shows that the age and modality of language acquisition is an important determinant of adult linguistic performance. Studies on profoundly deaf children deprived of speech stimulation, and then provided with a cochlear implant giving them access to the speech frequencies, shows that congenitally deaf children implanted under the age of around 5 years are likely to perform better on speech perception and speech production tasks than children implanted at an older age. Further investigation is required to understand why these large individual differences exist. In addition, other key issues for research are the effects of compensatory visual and somatosensory development prior to implantation, whether there is a maturational delay that approximates to the period of speech deprivation prior to implantation, and whether there are a number of sensitive periods that together describe the cascade of processes that underlies language acquisition.
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Affiliation(s)
- K Robinson
- Nottingham Paediatric Cochlear Implant Programme, UK.
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Electrically-Evoked Cortical Activity in Cochlear Implant Subjects Can Be Mapped Using fMRI. Neuroimage 1998. [DOI: 10.1016/s1053-8119(18)31218-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Popelár J, Hartmann R, Syka J, Klinke R. Middle latency responses to acoustical and electrical stimulation of the cochlea in cats. Hear Res 1995; 92:63-77. [PMID: 8647747 DOI: 10.1016/0378-5955(95)00199-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The middle latency responses (MLR) to acoustical stimulation (A-MLR) as well as to electrical stimulation (E-MLR) of the inner ear were recorded in pentobarbital-anaesthetised cats. Monopolar and bipolar MLR recordings were performed with electrodes located at different places on the primary auditory cortex (AI). The cochlea was electrically stimulated (ES) through a single round-window electrode or through a multichannel intracochlear implant. The slope of amplitude-intensity functions of the A-MLR was steeper when the stimulus frequency of the acoustical stimuli corresponded to the tonotopical recording place on the auditory cortex. Other response properties (waveshape, thresholds and latencies) were related to the recording site and stimulus frequency in only two-thirds of animals. Parameters of E-MLRs evoked by high-frequency ( > 4 kHz) and low-intensity ES in hearing cats, which produced an electrophonic effect, were similar to parameters of acoustically evoked MLRs. In deafened cats, the properties of responses to extracochlear ES were different from those recorded to acoustical stimulation and they were almost uniform in all cortical places. Variations in thresholds, in latencies and in the slope of the amplitude-intensity functions of the E-MLRs recorded in individual tonotopical cortical places were observed when the auditory nerve was stimulated with different configurations of electrodes through a multichannel intracochlear implant.
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Affiliation(s)
- J Popelár
- Zentrum der Physiologie, J.-W. Goethe Universität Frankfurt, Frankfurt/ Main, Germany.
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Pelizzone M. Auditory magnetic fields in cochlear-implant patients. Physiol Meas 1993; 14 Suppl 4A:A81-4. [PMID: 8274990 DOI: 10.1088/0967-3334/14/4a/014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Neuromagnetic recordings were used to check if electrical stimulation of the auditory nerve in cochlear-implant patients activates cortical auditory areas in a similar manner as acoustic stimulation in normal hearing subjects or whether the excitation processes are different. The waveform of the evoked magnetic field complex elicited by electrical stimulation of the auditory nerve as well as the distribution of the magnetic responses over the head resemble that of auditory-evoked fields elicited by acoustic stimulation of normal subjects. The location and direction of the equivalent dipole are consistent with activation of the auditory cortex. Neuromagnetic recordings could be used in the future (i) to check activation of the auditory cortices in cochlear-implant patients; (ii) to gather information about the functional properties of this activity, and (iii) to study the integrity of central auditory pathways in totally deaf patients.
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Affiliation(s)
- M Pelizzone
- Department of Otolaryngology, Cantonal University Hospital, Geneva, Switzerland
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