Onset Of Deafness Research Articles

Underlying dimensions of real-time word recognition in cochlear implant users

Word recognition is a gateway to language, linking sound to meaning. Prior work has characterized its cognitive mechanisms as a form of competition between similar-sounding words. However, it has not identified dimensions along which this competition varies across people. We sought to identify these dimensions in a population of cochlear implant users with heterogenous backgrounds and audiological profiles, and in a lifespan sample of people without hearing loss. Our study characterizes the process of lexical competition using the Visual World Paradigm. A principal component analysis reveals that people’s ability to resolve lexical competition varies along three dimensions that mirror prior small-scale studies. These dimensions capture the degree to which lexical access is delayed (“Wait-and-See”), the degree to which competition fully resolves (“Sustained-Activation”), and the overall rate of activation. Each dimension is predicted by a different auditory skills and demographic factors (onset of deafness, age, cochlear implant experience). Moreover, each dimension predicts outcomes (speech perception in quiet and noise, subjective listening success) over and above auditory fidelity. Higher degrees of Wait-and-See and Sustained-Activation predict poorer outcomes. These results suggest the mechanisms of word recognition vary along a few underlying dimensions which help explain variable performance among listeners encountering auditory challenge.

Genome-wide association study for age-related hearing loss in CFW mice.

Age-related hearing impairment is the most common cause of hearing loss and is one of the most prevalent conditions affecting the elderly globally. It is influenced by a combination of environmental and genetic factors. The mouse and human inner ears are functionally and genetically homologous. Investigating the genetic basis of age-related hearing loss (ARHL) in an outbred mouse model may lead to a better understanding of the molecular mechanisms of this condition. We used Carworth Farms White (CFW) outbred mice, because they are genetically diverse and exhibit variation in the onset and severity of ARHL. The goal of this study was to identify genetic loci involved in regulating ARHL. Hearing at a range of frequencies was measured using Auditory Brainstem Response (ABR) thresholds in 946 male and female CFW mice at the age of 1, 6, and 10 months. We obtained genotypes at 4.18 million single nucleotide polymorphisms (SNP) using low-coverage (mean coverage 0.27x) whole-genome sequencing followed by imputation using STITCH. To determine the accuracy of the genotypes we sequenced 8 samples at >30x coverage and used calls from those samples to estimate the discordance rate, which was 0.45%. We performed genetic analysis for the ABR thresholds for each frequency at each age, and for the time of onset of deafness for each frequency. The SNP heritability ranged from 0 to 42% for different traits. Genome-wide association analysis identified several regions associated with ARHL that contained potential candidate genes, including Dnah11, Rapgef5, Cpne4, Prkag2, and Nek11. We confirmed, using functional study, that Prkag2 deficiency causes age-related hearing loss at high frequency in mice; this makes Prkag2 a candidate gene for further studies. This work helps to identify genetic risk factors for ARHL and to define novel therapeutic targets for the treatment and prevention of ARHL.

Functional Outcomes from Cochlear Implants in Children with Acquired Hearing Loss: Case Studies

Purpose: Early identification of postlingual hearing loss (HL) and knowing its probable cause is of great significance. Causes that result in irreversible profound HL require immediate radiological investigation and intervention to decide the best listening device.Methods: Case reports of three children with acquired HL using cochlear implant (CI) are being presented to understand the functional outcomes in domains of audition and language skills after 12 months of CI use. The age of onset of deafness and implantation were not identical. Etiology of deafness was meningitis in two cases and viral infection in the other. Consent was obtained from the parents for participating in the study. Case history review was conducted to collect demographic and audiological details of the participants. Functional benefits from CI in those children were assessed in the domains of auditory and language skills using standardized assessment tools respectively.Results: Improvements in all domains of auditory and language skills were observed. However, the degree of benefits depended on the duration of deafness, etiology of deafness, age at onset of deafness, age at implantation and effectiveness of intervention.Conclusions: The results of the study can be used during pre-implant CI counselling to facilitate development of real expectations about the functional benefits of CI in children with acquired HL due to various reasons and showed the importance of early cochlear implantation following the diagnosis. These case presentations give an understanding of the various factors that can affect the functional outcome from CI in children with post-lingual HL.

Fundamental dimensions of real-time spoken word recognition in cochlear implant users

Spoken word recognition is a sophisticated cognitive process that maps incoming speech to meaning. For young, normal-hearing adults, word recognition is served by a competition process which plays out incrementally as speech unfolds. Candidates that match the input are activated and compete as mismatching candidates are suppressed. It remains unclear how this process changes in other listeners. Previous results from small-scale studies suggest three dimensions: 1) the speed of activating words (Activation Rate), affected by development and aging; 2) the degree of ultimate competitor suppression (Sustained Activation), affected by hearing loss; and 3) the delay of competition entirely (Wait-and-See), affected by severe hearing loss. To investigate these dimensions, a large, heterogenous group of cochlear implant users (N = 101) completed a Visual World Paradigm task. A principal component analysis supported these three dimensions. Each dimension was predicted by different demographic or auditory factors (onset of deafness, auditory fidelity, age), and each predicted outcomes over and above auditory fidelity. This suggests that these are orthogonal dimensions along which listeners vary, not all-or-nothing strategies. This work identifies the degrees of freedom that can extend theories of word recognition to account for a range of experiences and contexts.

Abnormal Innervation, Demyelination, and Degeneration of Spiral Ganglion Neurons as Well as Disruption of Heminodes are Involved in the Onset of Deafness in Cx26 Null Mice.

GJB2 gene mutations are the most common causes of autosomal recessive non-syndromic hereditary deafness. For individuals suffering from severe to profound GJB2-related deafness, cochlear implants have emerged as the sole remedy for auditory improvement. Some previous studies have highlighted the crucial role of preserving cochlear neural components in achieving favorable outcomes after cochlear implantation. Thus, we generated a conditional knockout mouse model (Cx26-CKO) in which Cx26 was completely deleted in the cochlear supporting cells driven by the Sox2 promoter. The Cx26-CKO mice showed severe hearing loss and massive loss of hair cells and Deiter's cells, which represented the extreme form of human deafness caused by GJB2 gene mutations. In addition, multiple pathological changes in the peripheral auditory nervous system were found, including abnormal innervation, demyelination, and degeneration of spiral ganglion neurons as well as disruption of heminodes in Cx26-CKO mice. These findings provide invaluable insights into the deafness mechanism and the treatment for severe deafness in Cx26-null mice.

TMTC4 is a hair cell-specific human deafness gene.

Transmembrane and tetratricopeptide repeat 4 (Tmtc4) is a deafness gene in mice. Tmtc4-KO mice have rapidly progressive postnatal hearing loss due to overactivation of the unfolded protein response (UPR); however, the cellular basis and human relevance of Tmtc4-associated hearing loss in the cochlea was not heretofore appreciated. We created a hair cell-specific conditional KO mouse that phenocopies the constitutive KO with postnatal onset deafness, demonstrating that Tmtc4 is a hair cell-specific deafness gene. Furthermore, we identified a human family in which Tmtc4 variants segregate with adult-onset progressive hearing loss. Lymphoblastoid cells derived from multiple affected and unaffected family members, as well as human embryonic kidney cells engineered to harbor each of the variants, demonstrated that the human Tmtc4 variants confer hypersensitivity of the UPR toward apoptosis. These findings provide evidence that TMTC4 is a deafness gene in humans and further implicate the UPR in progressive hearing loss.

Bilateral simultaneous cochlear implants in children: Best timing of surgery and long-term auditory outcomes

PurposeEvaluate the hearing outcomes of bilateral deaf children implanted simultaneously and define the most appropriate timing for surgery. Materials and methodsAudiological CI results were retrieved in both the short-term and long-term period and compared by stratifying the patients into different subcohorts according to their age at surgery. Additional data collected were age at implant activation, etiology and timing of onset of deafness, presence of psychomotor delay. Resultsfifty-six bilaterally implanted children were included. The short-term outcomes differed significantly when comparing groups of different ages at implantation: younger patients achieved better aided pure tone audiometry results. Considering long-term follow-up, a significant correlation was identified between an early age at implantation and the hearing outcome at ages 2 to 5 years. Perceptive levels were better at 4 years of age in the younger group. No significant differences were found between children implanted at before 12 months and between 12 and 16 months of age. ConclusionsThe results of the analyzed follow-up data support the hypothesis that children implanted at before 24 months are expected to have better hearing performances. Nevertheless, these results are referred to a widely heterogeneous group of patients and the duration of auditory deprivation should be considered.

14 A Culturally and Linguistically Informed Approach to the Development of a Cognitive Screener for Deaf Adults using American Sign Language

Objective:When assessing individuals from diverse backgrounds, APA ethical principles emphasize the consideration of language and culture when selecting appropriate measures. Research among hearing, English-speaking individuals has shown the effects in identifying cognitive deficits when language, culture, and educational background are not considered in the selection and administration of measures (Ardilla, 2007). Among the Deaf community in the US, a minority group with a unique culture and language (American Sign Language: ASL), there have been few attempts to adapt existing English cognitive measures. Factors complicating this include research resources given the limited number of neuropsychologists and researchers who understand both the complexities of the measures as well as the linguistic and cultural factors within the Deaf population. The goal of the current project is to develop a culturally informed interpretation of a cognitive screening tool for appropriate use with older Deaf adults.Participants and Methods:Item selection was informed by MMSE data from Dean et al. (2009) and methods utilized by Atkinson et al. (2015). Items selection occurred through consultation with three neuropsychologists and graduate peers with either native signing abilities or demonstrated ASL fluency, as well as Deaf identities, cultural affiliation and or community engagement. Selection considered the potential for translation errors, particularly related to equivalence of translation from a spoken modality to a signed. Items were categorized into the following domains: Orientation, Attention, Memory, Language, Executive Functioning, Visuospatial, and Performance Validity. Two native signers (Deaf interpreters) provided formal translation of the items. The measure was piloted with 20 deaf and hard of hearing (DHH) adult signers (ages M=41.10, SD=5.50, Range=31-48). Items were prerecorded to standardize the administration, which was shown to participants through the screenshare function of Zoom software.Results:The average performance was 100.80 (SD=3.91)/ 105 possible points. Within the memory domain, some errors, especially for word selection on delayed recall, were noted which may be related to sign choice and dialect. Additionally, with culture-specific episodic memory items, participants 35% of participants were unable to provide a correct answer with qualitative responses indicating this information may be more familiar to a subset of the Deaf community that had attended Gallaudet University in Washington, D.C. There was a significant positive relationship between ASL fluency, determined by the ASL-Comprehension Test, and performance on the cognitive screener (r(18)=.54, p=.01) while age of onset of deafness (r(18)=-.16, p=.51) and age of ASL acquisition (r(18)= .21, p=.37), were not significant.Conclusions:Results of this preliminary project yielded a measure that benefited from inclusion of content experts in the field during the process of interpretation and translation. It appears appropriate for Deaf signers who are proficient in ASL. The pattern of correlations suggests the measure may be appropriate for use with fluent signers with experience in ASL acquisition. Further development of the measure should focus on appropriate items that address the diversity of the Deaf experience as well as continue to explore inclusive translation approaches.

Development of an Optimized Protocol for Cochlear Implant Care to Increase Cochlear Implant Access.

To develop an evidence-based protocol for audiology-based, cochlear implant (CI) programming in the first year after activation. Retrospective case review. CI program at a tertiary medical center. One-hundred seventy-one patients (178 ears; mean age at implantation, 62.3 yr; 44.4% female) implanted between 2016 and 2021 with postlingual onset of deafness and no history of CI revision surgery. Patients included here had confirmed CI programming optimization based on CI-aided thresholds in the 20- to 30-dB-HL range as well as upper stimulation levels guided by electrically evoked stapedial reflex thresholds. Consonant-nucleus-consonant monosyllabic word recognition scores in the CI-alone and bilateral best-aided conditions at five time points: preoperative evaluation, and 1, 3, 6, and 12 months after activation. For both the CI-alone and bilateral best-aided conditions, consonant-nucleus-consonant word recognition significantly improved from preoperative evaluation to all postactivation time points. For the CI-alone condition, no significant differences were observed between 3 and 6 months, or from 6 to 12 months after activation. In contrast, for the bilateral best-aided condition, significant differences were observed between 1 and 3 months, and 3 and 6 months, but no difference in scores between 6 and 12 months. Based on the current data set and associated analyses, CI centers programming adult patients could eliminate either the 3- or 6-month visit from their clinical follow-up schedule if patient mapping of lower and upper stimulation levels is validated via CI-aided audiometric thresholds and electrically evoked stapedial reflex thresholds, respectively.

Factors that influence outcomes and device use for pediatric cochlear implant recipients with unilateral hearing loss.

Candidacy criteria for cochlear implantation in the United States has expanded to include children with single-sided deafness (SSD) who are at least 5 years of age. Pediatric cochlear implant (CI) users with SSD experience improved speech recognition with increased daily device use. There are few studies that report the hearing hour percentage (HHP) or the incidence of non-use for pediatric CI recipients with SSD. The aim of this study was to investigate factors that impact outcomes in children with SSD who use CIs. A secondary aim was to identify factors that impact daily device use in this population. A clinical database query revealed 97 pediatric CI recipients with SSD who underwent implantation between 2014 and 2022 and had records of datalogs. The clinical test battery included speech recognition assessment for CNC words with the CI-alone and BKB-SIN with the CI plus the normal-hearing ear (combined condition). The target and masker for the BKB-SIN were presented in collocated and spatially separated conditions to evaluate spatial release from masking (SRM). Linear mixed-effects models evaluated the influence of time since activation, duration of deafness, HHP, and age at activation on performance (CNC and SRM). A separate linear mixed-effects model evaluated the main effects of age at testing, time since activation, duration of deafness, and onset of deafness (stable, progressive, or sudden) on HHP. Longer time since activation, shorter duration of deafness, and higher HHP were significantly correlated with better CNC word scores. Younger age at device activation was not found to be a significant predictor of CNC outcomes. There was a significant relationship between HHP and SRM, with children who had higher HHP experiencing greater SRM. There was a significant negative correlation between time since activation and age at test with HHP. Children with sudden hearing loss had a higher HHP than children with progressive and congenital hearing losses. The present data presented here do not support a cut-off age or duration of deafness for pediatric cochlear implantation in cases of SSD. Instead, they expand on our understanding of the benefits of CI use in this population by reviewing the factors that influence outcomes in this growing patient population. Higher HHP, or greater percentage of time spent each day using bilateral input, was associated with better outcomes in the CI-alone and in the combined condition. Younger children and those within the first months of use had higher HHP. Clinicians should discuss these factors and how they may influence CI outcomes with potential candidates with SSD and their families. Ongoing work is investigating the long-term outcomes in this patient population, including whether increasing HHP after a period of limited CI use results in improved outcomes.

Audiological and radiological study of eight polish patients with alpha-mannosidosis

Alpha-mannosidase catalyze lysosomal cleaving of mannose residues from glycoproteins. The enzyme is encoded by the MAN2B1 gene. Biallelic pathogenic variants cause enzymatic deficiency, which clinically results in alpha-mannosidosis (AM), an autosomal recessively inherited condition. Typical features observed in AM patients include intellectual disability, loss of speech, dysmorphic features, progressive motor problems, ataxia, hearing impairment and recurrent otitis. The cause of the latter is mainly attributed to immunodeficiency.The aim of our study was to demonstrate the otolaryngologic and hearing outcomes in patients with AM.The study group consisted of 8 AM patients: 6 males and 2 females, aged 2.5–37 yrs. The clinical course, dysmorphic ENT features, hearing status and the HRCT scans of the temporal bones were analyzed. MS Excel for Windows and Statistica software package were used for the comparison of interaural audiometric loss, mean hearing loss and mean hearing threshold for each patient's audiometric frequency tested.We identified ENT dysmorphic features in all of our AM patients, while the hearing loss was detected in 6 out of our 8 patients. For those cases, the onset of deafness was noted in the first decade of life, this impairment was sensorineural, of cochlear origin, bilateral, of a moderate degree (mean loss 62.76 dB; median 60 dB, standard deviation 12.5 dB), symmetrical and stable. The shape of the audiometric curves of our patients can be described as slightly sloping towards the higher tested frequencies, with a marked improvement at 4 kHz. The radiological examination revealed normal structures of the ears, with the exception of one case where a persistent otitis generated a cochlear gap. We therefore concluded that the hearing loss in our AM patients derived from cochlear impairment unrelated with recurrent otitis.

Short periods of perinatal acoustic experience alter the developmental trajectory of auditory cortex

Compared to hearing subjects, psychophysical studies have revealed specific superior visual abilities following hearing loss early in development. The neural substrate for these superior abilities resides in auditory cortex that have been reorganized through crossmodal plasticity. Furthermore, the cartography of auditory cortex is altered following the loss of auditory input early in life. This study examined how perinatal exposure to brief periods of acoustic stimulation alters the developmental trajectory of auditory cortex. Movement detection, localization in the visual periphery, and face discrimination learning are superior in congenitally deaf cats. To examine the role of acoustic experience in mediating these enhanced functions, hearing animals were chemically deafened at increasing ages postnatal. Animals had 1–16 weeks of acoustic exposure prior to deafness onset. Overall, >9 weeks of acoustic experience resulted in no enhanced visual abilities. With >4 weeks of acoustic exposure, enhanced motion detection was not evident. As acoustic experience increased during development, the overall size of auditory cortex, and the size of individual auditory areas also expanded. These results demonstrate that increasingly longer periods of perinatal acoustic experience result in reduced enhanced visual abilities and an increased size of auditory cortex.

Biallelic mutations in pakistani families with autosomal recessive prelingual nonsyndromic hearing loss.

Nonsyndromic autosomal recessive hearing loss (DFNB) is an etiologically heterogeneous disorder group showing a wide spectrum of onset ages and severity. DFNB genes are very diverse in their types and functions, making molecular diagnosis difficult. DFNB is particularly frequent in Pakistan, which may be partly due to consanguinity. This study was performed to determine the genetic causes in Pakistani DFNB families with prelingual onset and to establish genotype-phenotype correlation. Whole exome sequencing and subsequent genetic analysis were performed for 11 Pakistani DFNB families including eight consanguineous families. We identified eight pathogenic or likely pathogenic mutations in LOXHD1, GJB2, SLC26A4, MYO15A, and TMC1 from six families. The GJB2 mutations were identified in two families each with compound heterozygous mutations and a homozygous mutation. The compound heterozygous mutations in LOXHD1 ([p.D278Y] + [p.D1219E]) and GJB2 [p.M1?] + [p.G12Vfs*2]) were novel. The four missense or start-loss mutations were located at well conserved residues, and most in silico analysis predicted their pathogenicity. In addition to causative mutations, we found compound heterozygous mutations in PTPRQ as variants of uncertain significance. This study identified biallelic mutations as the underlying cause of early onset DFNB in six Pakistani families. This study will be helpful in providing an exact molecular diagnosis and treatment of prelingual onset deafness patients.

Whole genome sequencing for newborns—The devil is in the details

Whole genome sequencing for newborns—The devil is in the details

Surdité dans l’artérite à cellules géantes : à propos d’une observation

IntroductionHearing loss is a rare manifestation in giant cell arteritis. The different types of deafness are possible with a predominance of sensorineural deafness. Case reportWe report a 75-year-old woman who presented with typical manifestations of giant cell arteritis associated concomitantly with the occurrence of bilateral mixed hearing loss confirmed on the audiogram. Corticosteroids allowed a rapidly favorable clinical and biological outcome. The follow-up audiogram at 3 months was markedly improved and showed a decrease in sensorineural hearing loss and disappearance of conductive hearing loss. ConclusionAny rapid onset deafness in an inflammatory context in the elderly should lead to a search for giant cell arteritis. The diagnosis can be difficult in the absence of other typical manifestations, especially since the biopsy of the temporal artery most often comes back negative. Corticosteroids are usually effective.

Academic Resilience Among Deaf Learners During E-Learning in the COVID-19 Era

This study aimed to assess the contributory roles of parental involvement (PI), parental acceptance/rejection (PAR), academic self-efficacy (ASE), computer user self-efficacy (CUSE) vis-à-vis gender and the onset of deafness on the academic resilience (AR) of deaf learners who participated in e-learning during the pandemic. The Bioecological Systems Theory provided a framework for the study. Data was collected using a structured questionnaire from 292 (Male: n = 164; Female: n = 128; Mage = 16.5) deaf learners from 3 provinces in South Africa. Data generated was analysed with IBM SPSS 22 and IBM AMOS 26.0 packages. All the fit measures of the SEM fell within the acceptable range (χ2 = 69.15, df = 28, χ2/df = 2.46, IFI = 0.91, CFI = 0.94, GFI = 0.93, NFI = 0.96, and RMSEA = 0.062). According to the findings, PAR, ASE and CUSE had a directly significant relationship on the AR of deaf learners who participated in e-learning during the lockdowns. An indirect significant relationship was observed between the latent variables and academic resilience when observed through the onset of deafness. Based on the findings, appropriate recommendations were made.

Clinical Features and Influencing Factors for the Prognosis of Patients With Sudden Deafness.

BackgroundsStudies on risk factors influencing the prognosis of patients with sudden onset deafness are lacking.MethodsFrom March 2018 to March 2021, 500 patients, from the Tongde Hospital in Zhejiang Province, with sudden onset deafness were enrolled. We collected clinical information from the hospital medical records, including certain demographic characteristics, information related to sudden-onset deafness, and laboratory parameters. Univariate and multivariate analyses were performed to determine independent prognostic risk factors for patients with sudden deafness. Additionally, we also employed orthogonal partial least squares discriminant analysis (OPLS-DA) to analyze the data of these enrolled patients.ResultsThe baseline clinical characteristics of the enrolled patients were analyzed. Based on their prognoses, the included patients were divided into the overall effective and ineffective groups. Between these two groups, the univariate and multivariate analyses were performed. Age, type of hearing curve at the initial diagnosis, acute phase, and sudden deafness site were found to be independently associated with the prognoses of patients with sudden deafness (all P < 0.05). Through the OPLS-DA, the sudden deafness site was found to be an indicator with the highest predictive power.ConclusionsAge, type of hearing curve at the initial diagnosis, acute phase, and sudden deafness site were all independently correlated with the prognoses of patients with sudden deafness and, therefore, need to be emphasized.

Sound source localization patterns and bilateral cochlear implants: Age at onset of deafness effects.

The ability to determine a sound’s location is critical in everyday life. However, sound source localization is severely compromised for patients with hearing loss who receive bilateral cochlear implants (BiCIs). Several patient factors relate to poorer performance in listeners with BiCIs, associated with auditory deprivation, experience, and age. Critically, characteristic errors are made by patients with BiCIs (e.g., medial responses at lateral target locations), and the relationship between patient factors and the type of errors made by patients has seldom been investigated across individuals. In the present study, several different types of analysis were used to understand localization errors and their relationship with patient-dependent factors (selected based on their robustness of prediction). Binaural hearing experience is required for developing accurate localization skills, auditory deprivation is associated with degradation of the auditory periphery, and aging leads to poorer temporal resolution. Therefore, it was hypothesized that earlier onsets of deafness would be associated with poorer localization acuity and longer periods without BiCI stimulation or older age would lead to greater amounts of variability in localization responses. A novel machine learning approach was introduced to characterize the types of errors made by listeners with BiCIs, making them simple to interpret and generalizable to everyday experience. Sound localization performance was measured in 48 listeners with BiCIs using pink noise trains presented in free-field. Our results suggest that older age at testing and earlier onset of deafness are associated with greater average error, particularly for sound sources near the center of the head, consistent with previous research. The machine learning analysis revealed that variability of localization responses tended to be greater for individuals with earlier compared to later onsets of deafness. These results suggest that early bilateral hearing is essential for best sound source localization outcomes in listeners with BiCIs.

Влияние временного диапазона между последовательными оперативными вмешательствами при бинауральной кохлеарной имплантации

Bilateral cochlear implantation is becoming an optimal method of hearing and speech rehabilitation in patients with bilateral sensorineural hearing loss. Therefore, today, general principles for selecting patients for this type of treatment are being developed all over the world, approaches are being formed to determine indications and contraindications. The key argument for determining indications for bilateral cochlear implantation is the patient’s rehabilitation potential, which in turn is formed from a combination of various factors. One of the most significant of them is the time factor—namely, the time interval between the onset of deafness and the performance of surgery. For patients with the first cochlear implantation, the prognosis of rehabilitation is inversely related to the duration of this time delay. And for patients who are planning to install a second cochlear implant with sequential binaural cochlear implantation, the influence of the time factor is still a matter of debate. In our work, we present a description of our successful experience in the rehabilitation of patients with bilateral sensorineural hearing loss of the IV degree (profound) with a large time range (more than 5 years) between successive surgical interventions—cochlear implantations.

Cortical Auditory Evoked Potential in Adults With Cochlear Implants: A Comparison With Adults With Normal Hearing.

Background and ObjectivesTo examine the maturational status of the auditory cortex in adults with cochlear implants (CIs) using the latencies of the P1, N1, and P2 components of cortical auditory-evoked potentials (CAEPs).Subjects and MethodsA total of 25 adults with CIs and 25 age-matched, normal-hearing control subjects participated in this study. Specifically, patients with CIs were divided into three groups depending on their age of deafness onset: Group A comprised patients with prelingual deafness who had received CI during early childhood (n=7), Group B comprised patients with early childhood-onset, progressive deafness who had received CI during childhood (n=6), and Group C comprised patients with adult-onset deafness (n=12). The P1, N1, and P2 latencies of their CAEPs were then compared between CI patients and normal-hearing subjects.ResultsAll participants showed clear CAEP responses. P1 and N1 latencies in Group A and Group C patients were significantly longer than those in the control group. Meanwhile, Group B patients had significantly longer N1 and P2 latencies, as compared with those in the control group.ConclusionsPatients with prelingual deafness and those with early-childhood onset, progressive deafness who received CI developed primary and higher-order auditory areas postoperatively when they became adults. However, their auditory cortex maturational statuses seemed to be worse than that of normal-hearing individuals. Furthermore, adult patients with late-onset deafness might experience degenerative auditory cortex changes during the auditory deprivation period between deafness onset and cochlear implantation.