Effect Of Cochlear Implantation Research Articles

Neural Processing of Musical and Vocal Emotions Through Cochlear Implants Simulation.

Cochlear implants (CIs) partially restore the sense of hearing in the deaf. However, the ability to recognize emotions in speech and music is reduced due to the implant's electrical signal limitations and the patient's altered neural pathways. Electrophysiological correlations of these limitations are not yet well established. Here we aimed to characterize the effect of CIs on auditory emotion processing and, for the first time, directly compare vocal and musical emotion processing through a CI-simulator. We recorded 16 normal hearing participants' electroencephalographic activity while listening to vocal and musical emotional bursts in their original form and in a degraded (CI-simulated) condition. We found prolonged P50 latency and reduced N100-P200 complex amplitude in the CI-simulated condition. This points to a limitation in encoding sound signals processed through CI simulation. When comparing the processing of vocal and musical bursts, we found a delay in latency with the musical bursts compared to the vocal bursts in both conditions (original and CI-simulated). This suggests that despite the cochlear implants' limitations, the auditory cortex can distinguish between vocal and musical stimuli. In addition, it adds to the literature supporting the complexity of musical emotion. Replicating this study with actual CI users might lead to characterizing emotional processing in CI users and could ultimately help develop optimal rehabilitation programs or device processing strategies to improve CI users' quality of life.

Hearing rehabilitation with cochlear implants and cognitive abilities

The relevance of assessing cognitive functioning is increasing against the background of the continuing demographic changes. Up to a few years ago the focus was on the effects of cochlear implantation in children born deaf in comparison to healthy individuals. Currently, the question arises whether hearing rehabilitation in the elderly, e.g. by postlingual cochlear implantation, has a protective effect on cognitive functioning and therefore on the risk of onset of dementia. This review describes the association of cognitive functioning with hearing disorders and cochlear implantation. Historical aspects of intelligence testing are illustrated. Knowledge on cognitive aspects in elderly persons with hearing disorders and cochlear implants is rare in the currently available literature. Initial findings indicate apositive correlation between hearing improvement and cognitive functioning. Further studies are urgently required in order to elucidate appropriate guidelines for the treatment of patients with cognitive deficits and hearing impairment.

Cochlear implantation combined with subtotal resection of temporal bone in treatment of nasopharyngeal carcinoma after radiotherapy of temporal bone necrosis

Objective To investigate the effects of cochlear implantation combined with subtotal resection of temporal bone in treatment of nasopharyngeal carcinoma after radiotherapy of temporal bone necrosis. Methods A prospective study method was used, and 76 cases of nasopharyngeal carcinoma after radiotherapy of temporal bone necrosis from February 2013 to October 2015 in our hospital for diagnosis and treatment were selected. According to the open control paired principle,the patients were equally divided into observation group and control group, each of 38 cases. Both groups received subtotal temporal bone resection in the treatment, and the observation group received cochlear implant therapy. The surgical effect and hearing improvement of two groups were observed. Results All patients successfully completed surgery. In the observation group, the patients showed normal reactions to intraoperative electrode detection and postoperative electrode impedance, without electrode slippage. There were no statistical differences between the two groups in postoperative pneumothorax and other complication (P > 0.05). The sound intensity level of hearing test in postoperative 1 month in the observation group and control group were (21.23±5.22) dB and (28.42±4.19) dB, which was significantly lower than that in the preoperative 1d [(38.24±4.98) dB and (38.12±5.00) dB], with significantly statistical difference (P < 0.05). The postoperative 1 month of hearing and speech score in the observation group were (87.24±2.98) points and (82.10±3.91) points respectively, which were significantly higher than those in the control group [(73.02±5.30) points and (71.84 ±3.11) points] (P < 0.05). The two groups of postoperative 1 months of hearing and speech scores were also significantly higher than those in the preoperative 1 d [observation group: (34.29±3.49) points and (32.10±5.30) points; control group: (33.20±4.14) points and (31.98±4.92) points] (P < 0.05). Conclusion Cochlear implantation combined with subtotal resection of temporal bone in treatment of nasopharyngeal carcinoma after radiotherapy of temporal bone necrosis shows high safety and success rate, which can promote the improvement of hearing and speech ability, and be widely used in clinic. Key words: Nasopharyngeal neoplasms; Temporal bone; Osteonecrosis; Cochlear implants; Subtotal resection; Hearing

The effects of cochlear implantation on vestibular function in 1–4 years old children

ObjectivesAlthough cochlear implants offer an effective hearing restoration option in children with severe to profound hearing loss, concern continues to exist regarding the possible effects of cochlear implantation on the vestibular system and balance. MethodsIn a prospective cohort study, 27 children with bilateral profound hearing loss (all candidates for cochlear implantation) were evaluated for their vestibular function before and after cochlear implantation. Vestibular evaluations consisted of Vestibular Evoked Myogenic Potentials, caloric testing and the Head-Impulse Test. ResultsMean age at the time of cochlear implantation was 27.19 months. Without considering vestibular evaluation results, one of the ears was selected for surgery. Vestibular tests after surgery were not indicative of any statistically significant change in vestibular system or balance. ConclusionThis limited data shows that cochlear implantation did not impair the vestibular system of these patients. By the results of our study we may conclude that round window implantation does not have any disturbing impact on vestibular function in children. The generalization of this result needs further research.

Cochlear implant-related three-dimensional characteristics determined by micro-computed tomography reconstruction.

To explore the structural characteristics of the cochlea in three-dimensional (3D) detail using 3D micro-computed tomography (mCT) image reconstruction of the osseous labyrinth, with the aim of improving the structural design of electrodes, the selection of stimulation sites, and the effectiveness of cochlear implantation. Three temporal bones were selected from among adult donors' temporal bone specimens. A micro-CT apparatus (GE eXplore) was used to scan three specimens with a voxel resolution of 45 μm. We obtained about 460 slices/specimen, which produced abundant data. The osseous labyrinth images of three specimens were reconstructed from mCT. The cochlea and its spiral characteristics were measured precisely using Able Software 3D-DOCTOR. The 3D images of the osseous labyrinth, including the cochlea, vestibule, and semicircular canals, were reconstructed. The 3D models of the cochlea showed the spatial relationships and surface structural characteristics. Quantitative data concerning the cochlea and its spiral structural characteristics were analyzed with regard to cochlear implantation. The 3D reconstruction of mCT images clearly displayed the detailed spiral structural characteristics of the osseous labyrinth. Quantitative data regarding the cochlea and its spiral structural characteristics could help to improve electrode structural design, signal processing, and the effectiveness of cochlear implantation. Clin. Anat. 30:39-43, 2017. © 2016 Wiley Periodicals, Inc.

Hearing Instruments for Unilateral Severe-to-Profound Sensorineural Hearing Loss in Adults: A Systematic Review and Meta-Analysis

Objectives:A systematic review of the literature and meta-analysis was conducted to assess the nature and quality of the evidence for the use of hearing instruments in adults with a unilateral severe to profound sensorineural hearing loss.Design:The PubMed, EMBASE, MEDLINE, Cochrane, CINAHL, and DARE databases were searched with no restrictions on language. The search included articles from the start of each database until February 11, 2015. Studies were included that (a) assessed the impact of any form of hearing instrument, including devices that reroute signals between the ears or restore aspects of hearing to a deaf ear, in adults with a sensorineural severe to profound loss in one ear and normal or near-normal hearing in the other ear; (b) compared different devices or compared a device with placebo or the unaided condition; (c) measured outcomes in terms of speech perception, spatial listening, or quality of life; (d) were prospective controlled or observational studies. Studies that met prospectively defined criteria were subjected to random effects meta-analyses.Results:Twenty-seven studies reported in 30 articles were included. The evidence was graded as low-to-moderate quality having been obtained primarily from observational before-after comparisons. The meta-analysis identified statistically significant benefits to speech perception in noise for devices that rerouted the speech signals of interest from the worse ear to the better ear using either air or bone conduction (mean benefit, 2.5 dB). However, these devices also degraded speech understanding significantly and to a similar extent (mean deficit, 3.1 dB) when noise was rerouted to the better ear. Data on the effects of cochlear implantation on speech perception could not be pooled as the prospectively defined criteria for meta-analysis were not met. Inconsistency in the assessment of outcomes relating to sound localization also precluded the synthesis of evidence across studies. Evidence for the relative efficacy of different devices was sparse but a statistically significant advantage was observed for rerouting speech signals using abutment-mounted bone conduction devices when compared with outcomes after preoperative trials of air conduction devices when speech and noise were colocated (mean benefit, 1.5 dB). Patients reported significant improvements in hearing-related quality of life with both rerouting devices and following cochlear implantation. Only two studies measured health-related quality of life and findings were inconclusive.Conclusions:Devices that reroute sounds from an ear with a severe to profound hearing loss to an ear with minimal hearing loss may improve speech perception in noise when signals of interest are located toward the impaired ear. However, the same device may also degrade speech perception as all signals are rerouted indiscriminately, including noise. Although the restoration of functional hearing in both ears through cochlear implantation could be expected to provide benefits to speech perception, the inability to synthesize evidence across existing studies means that such a conclusion cannot yet be made. For the same reason, it remains unclear whether cochlear implantation can improve the ability to localize sounds despite restoring bilateral input. Prospective controlled studies that measure outcomes consistently and control for selection and observation biases are required to improve the quality of the evidence for the provision of hearing instruments to patients with unilateral deafness and to support any future recommendations for the clinical management of these patients.

Effect of cochlear implantation on sound localization for patients with unilateral sensorineural hearing loss

The aim of this review was to examine the current literature regarding application of cochlear implantation on patients with unilateral sensorineural hearing loss (USNHL) for improvement on sound localization. The literature were searched in the PubMed database with 'cochlear implantation AND single-sided deafness' or 'cochlear implantation AND unilateral deafness' as keywords. The publication date of the articles was up to 2015-2-12. A total of 12 articles were included. The results show that the ability of sound localization for most of the USNHL subjects (90%) with cochlear implantation was significantly improved than that without CI, which suggests that CI is a superior auditory rehabilitation treatment than BAHA and CROS hearing aids for patients with USNHL, because of the re-establishment of the benefits of binaural hearing. In addition, the benefit of CI for USNHL requires a period of auditory experience or training. About 30% subjects showed significantly improvement on sound localization ability after CI worked for three months. For most of the patients (90%), the sound localization ability improved after CI worked for six months. When CI worked for nine months, all the subjects would show improvement on sound localization ability. Sound localization of the USNHL subjects with a CI is based primarily on interaural level differences (ILD) while interaural time differences (ITD) provide little advantage or probably not perceptible at all. The younger subject suffers from USNHL, the stronger the plasticity of the auditory center shows, which results in more obvious degeneration of the affected side and adaptive enhancement of the contralateral side of the auditory pathway. Similarly, the longer duration of USNHL lead to more obvious degeneration of the affected side and adaptive enhancement of the contralateral side. An adaptive enhancement of auditory pathway corresponding to the healthy ear will rely more on the monaural spatial cues that available to the intact ear to improve the sound localization in the horizontal plane. Contrarily, the degeneration of auditory pathway corresponding to the USNHL may be limited to re-reorganize from auditory deprivation even after CI, which may increase the risk that a few subjects cannot re-establish the binaural benefits after CI. Therefore, patients with USNHL should accept CI as soon as possible to obtain good binaural benefits, especially for sound localization.

Minimally invasive surgical techniques of cochlear implantation withround window pathways in young children

Objective:To discuss the minimally invasive surgical techniques and the effect of cochlear implantation with round window pathways in young children(≤3 years).Method:One hundred and sixty patients with bilateral profound sensorineural hearin loss received MED-EL cochlear implantation,including 144 cases of normal middle and inner ear,4 cases of Mondini deformity,12 cases of large vestibular aqueduct syndrome.Result:Of 160 patients underwent CIs,148 patients were performed with round window pathways,the rate was 92.5%. Iit's difficult to exposure round window in 12 patients,performing from promontory.All electrodes of 158 cases with unilateral CI and 2 cases with bilateral CI were implanted successfully,in which the CI went normally and electrode array were protected well.All implant devices had worked normally and all patients had performed well during an average follow-up period of 8 month-3 years.Post-operatively complications of cerebrospinal fluid leakage,facial nerve injury haven't been found.Conclusion:Cochlear implantation could be performed in patients wit with round window pathways,and it is a safe and effective way in young children.

The effects of cochlear implantation in Japanese single-sided deafness patients: five case reports

Conclusion Cochlear implantation (CI) for Japanese single-sided deafness patients resulted in improved speech perception, increased sound localization accuracy, and reduced tinnitus handicap. Objectives This study reports results for five adult SSD cases with CI, focusing on the benefits they obtained in terms of speech recognition, sound localization, and tinnitus handicap. Methods Five Japanese patients meeting the eligibility criteria were included in this study. All patients were implanted with a fully inserted MED-EL Concerto FLEX28® implant (MED-EL, Innsbruck, Austria). Speech perception outcomes in noise, as well as sound localization and tinnitus disturbance, were assessed pre-surgically and at 1, 3, 6, and 12 months after CI activation. Results The Japanese monosyllable test score in noise improved gradually after implantation. In some cases, speech perception ability appeared unstable, particularly in the first 1–6 months after implantation. The sound localization ability showed marked improvement in all cases, with the disturbance to daily life caused by tinnitus also decreasing in all cases from the early post-operative period.

Music-based rehabilitation in cochlear implant users: Insights from brain-plasticity research

Music-based rehabilitation in cochlear implant users: Insights from brain-plasticity research

Language Development in Profoundly Prelingually Deaf Children with Cochlear Implantation: Long-Term Outcomes

Received March 9, 2016 Revised May 5, 2016 Accepted May 9, 2016 Address for correspondence Kyu-Yup Lee, MD Department of OtorhinolaryngologyHead and Neck Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu 41944, Korea Tel +82-53-420-6322 Fax +82-53-420-4524 E-mail kylee@knu.ac.kr Background and ObjectivesZZIt is well established that cochlear implantation provides significant benefits for prelingually profound deaf children. However, there are few studies that examined the long-term outcome of cochlear implantation beyond 10 years in prelingually deaf children. The purpose of this study was to examine the long-term benefit of cochlear implantation for children with more than 10 years of experience of using cochlear implantation, regarding auditory performance and academic status. We then determined the age effect of cochlear implantation on auditory performance for prelingually deaf children. Subjects and MethodZZThe longitudinal development of auditory performance of 119 deaf children was analyzed after cochlear implantation. Among the 119 children, 58 were included for analysis. ResultsZZThe children who received cochlear implanst at younger age showed significantly better auditory performance. Age at which implantation had been performed had a significant effect on the development of auditory performance before 4 years of age. Many children continued to demonstrate improvements of auditory performance upto five years of implant use. Some showed development of auditory performance upto 10 years cochlear implantation. ConclusionZZThe present result indicates that speech perception and performance for children continue to improve over time from 5 upto 10 years while using cochlear implant. The use of earlier cochlear implantation was demonstrated to provide better auditory performance. The age at which implantation was performed was one of the important factors influencing the long-term outcome of cochlear implantation. Korean J Otorhinolaryngol-Head Neck Surg 2016;59(7):502-9

Presence of cytomegalovirus in the perilymphatic fluid of patients with profound sensorineural hearing loss caused by congenital cytomegalovirus infection

Conclusion: Not all patients diagnosed with congenital infection using umbilical cord assay were found to be positive for CMV-DNA by perilymphatic fluid assay. In addition, a CMV-DNA-positive result was observed in one patient who had not been diagnosed with congenital infection. Sampling of perilymphatic fluid from a large population of patients with congenital SNHL caused by congenital CMV infection or of unknown etiology is required to determine the prevalence of CMV-related profound HL. Objectives: Sensorineural hearing loss (SNHL) is one of the most frequent manifestations in patients with congenital cytomegalovirus (CMV) infection. Using dried umbilical cord, a PCR-based assay was recently developed for the retrospective detection of congenital CMV infection. This study analyzed the presence of CMV in the perilymphatic fluid and evaluated differences in the effect of cochlear implantation between CMV-positive and -negative groups. Method: Perilymphatic fluid was collected from each patient at the time of cochlear implantation and analyzed for the presence of CMV using a PCR method. Results: The perilymphatic fluid in two of the five patients suffering from congenital CMV infection and in one of the 17 patients without congenital CMV infection was found to be positive for CMV.

Why repetition? Repetitive babbling, auditory feedback, and cochlear implantation

This study investigated the reduplicated, or repetitive vocalizations of hearing infants and infants with profound hearing loss with and without cochlear implants using a new measure of repetition in order to address questions not only about the effects of cochlear implantation on repetitive babbling, but also about the reason repetitive vocalizations occur at all and why they emerge around 7 or 8months of age in hearing infants. Participants were 16 infants with profound hearing loss and 27 hearing infants who participated at a mean age of 9.9months and/or a mean age of 17.7months. Mean age at cochlear implantation for infants with profound hearing loss was 12.9months, and mean duration of implant use was 4.2months. The data show that before cochlear implantation, repetitive vocalizations were rare. However, 4months after cochlear implant activation, infants with hearing loss produced both repetitive vocalizations and repetitions per vocalization at levels commensurate with their hearing peers. The results support the hypothesis that repetition emerges as a means of vocal exploration during the time when hearing infants (and infants with cochlear implants) form auditory–motor representations and neural connections between cortical areas active in syllable production and syllable perception, during the transition from nonlinguistic to linguistic vocalization.

Effect of cochlear implantation on bilateral perceived tinnitus of postlingually deafened patients

The aim of the study was to evaluate the effects of cochlear implantation on bilateral perceived tinnitus of postlingually deafened patients. Total of 32 postlingually deafened cochlear implant recipients (13 males, 19 females; 31 unilateral,1 bilateral cochlear implantation) with bilateral tinnitus were assessed by Tinnitus Handicap Inventory (THI) before and after implantation. Furthermore, characteristics information of tinnitus were recorded to analyze the variety of tinnitus. Intensity of tinnitus in ispilateral and contralateral ears was investigated when cochlear implant was switched on and off. Statistical analysis was performed by SPSS 18.0. Twenty-two patients (71.0%) got a decreased THI score of more than 20 points after the operation. The average THI score of pre-operation was 56.4±18.1, and post-operation score was 24.7±22.7. A paired-samples t test analysis showed a significant difference of the THI total scores (t=8.037, P<0.05). Tinnitus in the ipsilateral ear improved in 81.9% (27/33) patients and 18.2% (6/33) unchanged. Tinnitus in the contralateral ear improved in 71.0% (22/31) patients, 16.1% (5/31) unchanged and 12.9% (4/31) worsen. Tinnitus of ipsilateral ears improved or abolished in 97.0% (32/33) patients, while 83.9% (26/31) of contralateral ear got reduction or absence of loudness when cochlear implant was switched on. As an electrical stimulation treatment method, cochlear implant has the inhibitory effect on tinnitus. However, cases of tinnitus aggravation were found, further data is still necessary before considering CI as a treatment of tinnitus.

Relationship between intracochlear electrode position and tinnitus in cochlear implantees

Conclusion: Cochlear implant electrode position has an impact on the rate of tinnitus suppression and generation. Objective: Suppression of pre-operative tinnitus or a generation of a new tinnitus in cochlear implantees is a known effect of cochlear implantation. The aim of the current study was to evaluate different cochlear implant electrode positions and their relationship with tinnitus suppression and tinnitus generation. Method: This study retrospectively evaluated four groups of CI recipients with radiologically evaluated electrode positions in relation to their subjective tinnitus quality, as evaluated by an analogue loudness scale (ALS) and a questionnaire. Group 1 consisted of 19 patients with a scalar change of the electrode position. Group 2 consisted of 18 patients with a scala tympani position and a perimodiolar electrode. Group 3 consisted of 10 patients with a scala tympani position and a lateral wall electrode. Group 4 consisted of eight patients with a scala vestibuli position. Results: An overall tinnitus suppression rate of 45.9% and a generation of a new tinnitus or the deterioration of an existing one of 5.6% were observed. A significant difference in tinnitus suppression was found between groups 1 and groups 2, 3, and 4 in tinnitus suppression and tinnitus generation.

Putting Research into Practice for Autism Spectrum Disorder

Putting Research into Practice for Autism Spectrum Disorder

The economic and societal benefits of adult cochlear implant implantation: A pilot exploratory study

BackgroundCochlear implantation has been shown to result in significant improvements in communication and quality of life, but little is known about the effect of cochlear implantation and changes in a person's employment status and earning potential. The purpose of this study is to measure the extent to which personal income changes in people who receive a cochlear implant.MethodsWe mailed a survey to a random selection of 150 cochlear implantees who receive health services in a large urban setting. Of the 93 respondents, 65 were eligible for inclusion. Demographics, current income and income prior to implantation were recorded into income categories.ResultsWith a 6.6-year mean duration from cochlear implantation, it was found that 31% of respondents had increased income enough to move income brackets, with a mean category rise of $10 021. Forty participants reported working pre-implant, while 49 reported working post-implant.ImplicationsOur results suggest preliminary evidence for an association between cochlear implantation and income. Increased accesses to cochlear implantation may provide opportunities for competitive employment and associated economic benefits for the individual, their families, and society.

Assessing Deaf Awareness Training: Knowledge and Attitudes of Recent Genetic Counseling Graduates

Research suggests that when healthcare providers lack cultural competence, minority groups, including the Deaf community, are adversely affected. Although most genetic counseling programs incorporate cultural competency training into their curricula, the extent and impact of Deaf awareness training is unknown. The purpose of this study is to assess Deaf awareness training of recent graduates and its impact on knowledge of deafness and Deaf culture, and attitudes toward deaf people. Genetic counselors who graduated within the past 5years were invited to participate in an anonymous, online survey. Of the 135 respondents, 26% reported no Deaf awareness training and 51% reported limited training (1-2h) conducted primarily by program instructors. Nearly one-third felt their Deaf awareness training was insufficient. Respondents lacked knowledge regarding effects of cochlear implants on residual hearing, communication between deaf children and hearing parents, and working with sign language interpreters. However, scores on knowledge of deafness and Deaf culture items and scores on attitudes toward deaf people scale did not differ significantly between respondents who had Deaf awareness training and those who did not. These findings suggest that genetic counseling students may not receive adequate Deaf awareness training. Future efforts should focus on increasing Deaf awareness in genetic counseling students, and investigating whether this change improves genetic counseling experiences for Deaf individuals.

Cochlear Implantation in Ménière's Disease.

Though the effects of cochlear implantation (CI) on patients with hearing loss has been well described, its effect on the auditory and vestibular symptoms in patients with Ménière's disease (MD) has not been firmly established. To determine whether CI in patients with MD improves hearing performance as measured by standard post-CI audiometric testing and to describe the impact of CI on subjective auditory and vestibular quality-of-life measures. Retrospective review of all patients with MD 18 years or older who met diagnostic criteria for definite MD and underwent CI at Wake Forest University Baptist Medical Center, a tertiary care academic medical center, from 2000 through 2012. Patients were invited to answer questions regarding their current hearing ability, subjective perception of symptoms, and functional status related to their MD before and after CI. Patient records were reviewed for pertinent information. Results were then analyzed for statistical significance. Pre-CI and post-CI sentence testing scores, frequency and severity of MD vestibular and auditory symptoms via the MD Functional Level Scale (FLS), and hearing quality of life via the Hearing Handicap Index were reviewed. Eleven CIs were performed in 10 patients. Mean long-term follow-up was 41 months. The mean age at first implantation was 64 years. The mean sentence testing scores in quiet improved from 22.8% before CI to 77.0% after CI (P < .001) at the most recent follow-up. Mean (SD) pre-CI and post-CI MD-FLS vestibular scores were similar: 3.9 (1.9) and 3.4 (1.9) (P = .52). Patients with MD who undergo CI are capable of achieving substantial receptive communication improvement comparable to the gains experienced by patients without MD. Implantation seems to neither adversely alter the natural history of vestibular function nor notable exacerbate auditory symptoms.

Some neuromyths concerning the effectiveness of cochlear implants: Inferring function from dysfunction

Cochlear implants provide profoundly deaf infants and young children with access to critical temporal and spectral patterns of speech needed for language development. Despite the enormous benefits of cochlear implants, many controversial questions remain. I will consider ten pressing issues that are the focus of current efforts in the field: (1) individual variability in speech and language outcomes, (2) neuroplasticity and early implantation, (3) learning and linguistic experience, (4) linguistic vs indexical channels in speech perception, (5) bilateral vs. unilateral implantation, (6) Contribution of other neural and cognitive systems, (7) early predictors of outcomes and risk factors, (8) workload and mental effort, (9) speech in noise, and (10) acoustic simulations in normal-hearing listeners. These issues raise important theoretical questions about basic processes in speech perception and spoken language processing. Cochlear implant research may be viewed as a “model system” enabling inferences about normal function from the study of dysfunction providing additional converging support for the proposal that the ear does not function in isolation from the rest of the brain; it is an inseparable component of a complex adaptive self-organizing system that evolved to support the perception and production of spoken language. [Work supported by NIH Grants: R01 DC-XYZ and DC-ABC to Indiana University.]