Auditory Attention Ability under Dichotic Dual-Task Situation in Adults with Listening Difficulties.

INTRODUCTION: Recent studies have reported poor cognition, such as attention and working memory, in adults with listening difficulties (LiD). However, they do not adequately describe the actual state of poor attention ability in adults with LiD. We examined the state of auditory attention in adults with and without LiD in tasks requiring multiple attention controls. METHODS: Twenty-one adults who had normal hearing but complained about LiD encountered during everyday life and 22 healthy controls were included. We presented a target detection task using an odd-ball format for one ear and a sentence repetition task for the other ear. In the target detection task, participants listened to the 1,000-Hz tone served as the standard stimulus, while they had to accept a 2,000-Hz tone presented as the deviant stimulus. In the sentence repetition task, short sentences were presented. The stimuli presented to them were played on a personal computer at the most comfortable level. The participants heard these stimuli through headphones. They were required to press a key for standard stimuli in the target detection task and repeat what they heard immediately in the repetition task. We compared the response accuracy for each ear task between adults with and without LiD. RESULTS: Our results showed that there were significant differences between the participant groups in the auditory dual-task under the dichotic listening situation. When examined individually, four adults with LiD had decreased scores in both the sentence repetition and target detection task, while the other nine participants showed a bias toward either task. Furthermore, the analysis of reaction time for pressing button revealed that the standard deviation of reaction time was extended in participants who scored poorly in either of the ear tasks. On the other hand, all adults without LiD were able to conduct the auditory dual-task exactly and promptly. CONCLUSION: The results suggest that adults with LiD have difficulties in appropriately allocating various cognitive abilities required for each task. We concluded that auditory attention is an important ability to conduct the auditory dual-task, and this is applicable for adults with LiD. Therefore, we believe that it is necessary to use auditory tests that require complex attentional abilities in listening, such as those required in daily life, to assess adults with LiD.

Evoked Potentials by Tone Burst on the Auditory Cortices in Cats -Comparison of Off Responses in Awake and Anesthetized Conditions.

BACKGROUND: Auditory Brainstem Response (ABR) recording in awake is essential to detect off-responses. This study clarified whether after-termination responses on ABR were offset responses, off-responses or a mixture of the two. METHODS: Evoked potentials in the auditory cortex of cats in response to tone burst stimuli were recorded, and off responses were examined with chronically implanted electrodes. RESULTS: When the fall time at the end of sound stimuli was 5ms or longer, the amplitude of click responses was extremely small. Under this condition, evoked potentials in response to two types of tone bursts (long and short) were recorded.By calculating the differences in evoked potentials between the two-tone bursts, off responses were separated. Off responses were generated during wakefulness by auditory cortex stimulation but were not observed under anesthesia. Pronounced off responses, which were middle latency responses exhibiting bis positive waves, were obtained in response to sound stimuli with a frequency of 2 kHz or higher. Vertex stimulation did not induce off responses either during wakefulness or under anesthesia. CONCLUSION: Off responses are derived from synchronous responses of neurons in the auditory cortex, which are generated when the neurons detect attenuation in the stimulus strength at the end of tone burst stimuli.

Autosomal dominant optic atrophy with OPA1 gene mutations accompanied by auditory neuropathy and other systemic complications in a Japanese cohort.

Purpose: This study aimed to describe the genetic and clinical characteristics of four Japanese patients with autosomal dominant optic atrophy (DOA) accompanied by auditory neuropathy and other systemic complications (i.e., DOA-plus disease). Methods: Four patients from four independent families underwent comprehensive ophthalmic and auditory examinations and were diagnosed with DOA-plus disease. The disease-causing gene variants in the OPA1 gene were identified by direct sequencing. The genetic and clinical data of 48 DOA patients without systemic complications-that is, with simple DOA-were compared to those of DOA-plus patients. Results: DOA-plus patients noticed a decrease in vision before the age of 14 and hearing impairment 3 to 13 years after the development of visual symptoms. Two patients had progressive external ophthalmoplegia, and one patient had vestibular dysfunction and ataxia. The DOA-plus phenotypes accounted for 13.3% (4/30) of the families with the OPA1 gene mutations. Each DOA-plus patient harbored one of the monoallelic mutations in the OPA1 gene: c.1334G>A, p.R445H, c.1618A>C, p.T540P, and c.892A>C, p.S298R. Missense mutations accounted for 100% (4/4) of the DOA-plus families and only 11.5% (3/26) of the families with simple DOA. Conclusions: All the patients with the DOA-plus phenotype carried one of the missense mutations in the OPA1 gene. They all had typical ocular symptoms and signs of DOA in their first or second decade, and other systemic complications-such as auditory neuropathy, vestibular dysfunction, and ataxia-followed the ocular symptoms. We should consider the occurrence of extraocular complications in cases with DOA, especially when they carry the missense mutations in the OPA1 gene.

Deterioration in Distortion Product Otoacoustic Emissions in Auditory Neuropathy Patients With Distinct Clinical and Genetic Backgrounds.

OBJECTIVES: Auditory neuropathy (AN) is a clinical disorder characterized by the absence of auditory brainstem response and presence of otoacoustic emissions. A gradual loss of otoacoustic emissions has been reported for some cases of AN. Such cases could be diagnosed as cochlear hearing loss and lead to misunderstanding of the pathology when patients first visit clinics after the loss of otoacoustic emissions. The purpose of this study was to investigate the time course of changes in distortion product otoacoustic emissions (DPOAEs) in association with patients' genetic and clinical backgrounds, including the use of hearing aids. DESIGN: DPOAE measurements from 31 patients with AN were assessed. Genetic analyses for GJB2, OTOF, and mitochondrial m.1555A> G and m.3243A> G mutations were conducted for all cases, and the analyses for CDH23 and OPA1 were conducted for the selected cases. Patients who were younger than 10 years of age at the time of AN diagnosis were designated as the pediatric AN group (22 cases), and those who were 18 years of age or older were designated as the adult AN group (9 cases). DPOAE was measured at least twice in all patients. The response rate for DPOAEs was defined and analyzed. RESULTS: The pediatric AN group comprised 10 patients with OTOF mutations, 1 with GJB2 mutations, 1 with OPA1 mutation, and 10 with indefinite causes. Twelve ears (27%) showed no change in DPOAE, 20 ears (46%) showed a decrease in DPOAE, and 12 ears (27%) lost DPOAE. Loss of DPOAE occurred in one ear (2%) at 0 years of age and four ears (9%) at 1 year of age. The time courses of DPOAEs in patients with OTOF mutations were divided into those with early loss and those with no change, indicating that the mechanism for deterioration of DPOAEs includes not only the OTOF mutations but also other common modifier factors. Most, but not all, AN patients who used hearing aids showed deterioration of DPOAEs after the start of using hearing aids. A few AN patients also showed deterioration of DPOAEs before using hearing aids. The adult AN group comprised 2 patients with OPA1 mutations, 2 with OTOF mutations, and 5 with indefinite causes. Four ears (22%) showed no change in DPOAE, 13 ears (72%) showed a decrease, and one ear (6%) showed a loss of DPOAE. Although the ratio of DPOAE decrease was higher in the adult AN group than in the pediatric AN group, the ratio of DPOAE loss was lower in the adult AN group. DPOAE was not lost in all four ears with OPA1 mutations and in all four ears with OTOF mutations in the adult group. CONCLUSIONS: DPOAE was decreased or lost in approximately 70% of pediatric and about 80% of adult AN patients. Eleven percent of pediatric AN patients lost DPOAEs by 1 year of age. Genetic factors were thought to have influenced the time course of DPOAEs in the pediatric AN group. In most adult AN patients, DPOAE was rarely lost regardless of the genetic cause.

Temporal Bone Histopathology of Atypical Cogan Syndrome.

Cogan's syndrome is a rare disorder first clinically defined in 1945, characterized by nonsyphilitic interstitial keratitis and progressive audiovestibular symptoms. Later, patients with audiovestibular dysfunction and various types of inflammatory eye disease were classified as having atypical Cogan's syndrome. The etiology and pathogenesis of Cogan's syndrome remain largely unknown. Here, we report a case of atypical Cogan's syndrome with a histological assessment of the temporal bone during the acute disease period. Temporal bone histology was compared to age- and gender-matched normal control, and our findings revealed endolymphatic hydrops and degenerative changes in various parts of the inner ear. Laryngoscope, 2024.

The error patterns of phonemes in children with prelingual hearing loss: A comparison between hearing aid and cochlear implant users.

OBJECTIVE: To reveal differences in error pattern of phonemes and articulation between children using cochlear implants (CIs) and those using hearing aids (HAs) due to prelingual hearing disorder and help the education of children with prelingual hearing loss. METHOD: Children with prelingual hearing loss who were receiving auditory-verbal preschool education at an auditory center for hearing-impaired children (Fujimidai Auditory Center, Tokyo, Japan) from 2010 to 2020 were analyzed retrospectively. All participants underwent pure tone audiometry and monosyllabic intelligibility tests. The error answers were categorized into five patterns which was characterized by the substitution, addition, omission, failure, and no response according to consonant errors. In addition, the consonant errors classified into the manner of articulation and the differences of error patterns were analyzed between the HA and the CI group descriptively. RESULTS: A total of 43 children with bilateral HAs and 46 children with bimodal CIs or bilateral CIs were enrolled. No significant between-group differences in median phoneme intelligibility were found. The most common error pattern was substitution in both HA and CI groups. The error number of addition pattern in the HA group was smaller than in the CI group. In both groups, the most common errors of articulation were flap errors, and the most common error patterns were flaps to nasals, nasals to nasals, plosives to plosives. In the HA group, plosives and nasals tended not to be recognized and in the CI group plosives were prone to be added to vowels. CONCLUSIONS: There were some different error patterns of articulation and consonant substitution between groups. Clarifying differences of phoneme that are difficult to hear and tend to be misheard would help for creating an effective approach to auditory training for children with hearing loss.

Prediction of Cochlear Implant Effectiveness With Surface-Based Morphometry.

OBJECTIVE: This study aimed to determine whether surface-based morphometry of preoperative whole-brain three-dimensional T1-weighted magnetic resonance imaging (MRI) images can predict the clinical outcomes of cochlear implantation. STUDY DESIGN: This was an observational, multicenter study using preoperative MRI data. SETTING: The study was conducted at tertiary care referral centers. PATIENTS: Sixty-four patients with severe to profound hearing loss (≥70 dB bilaterally), who were scheduled for cochlear implant (CI) surgery, were enrolled. The patients included 19 with congenital hearing loss and 45 with acquired hearing loss. INTERVENTIONS: Participants underwent CI surgery. Before surgery, high-resolution three-dimensional T1-weighted brain MRI was performed, and the images were analyzed using FreeSurfer. MAIN OUTCOME MEASURES: The primary outcome was monosyllable audibility under quiet conditions 6 months after surgery. Cortical thickness residuals within 34 regions of interest (ROIs) as per the Desikan-Killiany cortical atlas were calculated based on age and healthy-hearing control regression lines. RESULTS: Rank logistic regression analysis detected significant associations between CI effectiveness and five right hemisphere ROIs and five left hemisphere ROIs. Predictive modeling using the cortical thickness of the right entorhinal cortex and left medial orbitofrontal cortex revealed a significant correlation with speech discrimination ability. This correlation was higher in patients with acquired hearing loss than in those with congenital hearing loss. CONCLUSIONS: Preoperative surface-based morphometry could potentially predict CI outcomes and assist in patient selection and clinical decision making. However, further research with larger, more diverse samples is necessary to confirm these findings and determine their generalizability.

Developmental changes in the responsiveness of rat spiral ganglion neurons to neurotrophic factors in dissociated culture: differential responses for survival, neuritogenesis and neuronal morphology.

The way that the development of the inner ear innervation is regulated by various neurotrophic factors and/or their combinations at different postnatal developmental stages remains largely unclear. Moreover, survival and neuritogenesis in deafferented adult neurons is important for cochlear implant function. To address these issues, developmental changes in the responsiveness of postnatal rat spiral ganglion neurons (SGNs) to neurotrophin-3 (NT-3), brain-derived neurotrophic factor (BDNF) and leukemia inhibitory factor (LIF) were examined by using a dissociated cell culture system. SGNs at postnatal day (P) 0, P5 and P20 (young adult) were cultured with the addition of NT-3, BDNF, or LIF or of a combination of NT-3 and BDNF (N + B) or of NT-3, BDNF and LIF (ALL factors). SGNs were analyzed for three parameters: survival, longest neurite length (LNL) and neuronal morphology. At P0, SGNs required exposure to N + B or ALL factors for enhanced survival and the ALL factors combination showed a synergistic effect much greater than the sum of the individual factors. At P5, SGNs responded to a wider range of treatment conditions for enhanced survival and combinations showed only an additive improvement over individual factors. The survival percentage of untreated SGNs was highest at P20 but combinations of neurotrophic factors were no more effective than individual factors. LNL of each SGN was enhanced by LIF alone or ALL factors at P0 and P5 but was suppressed by NT-3, BDNF and N + B at P5 in a dose-dependent manner. The LNL at P20 was enhanced by ALL factors and suppressed by N + B. Treatment with ALL factors increased the proportion of SGNs that had two or more primary neurites in all age groups. These findings suggest that NT-3, BDNF, LIF and their combinations predominantly support different ontogenetic events at different developmental stages in the innervation of the inner ear.

Auditory brainstem implantation improves speech recognition in neurofibromatosis type II patients.

This prospective study aimed to determine speech understanding in neurofibromatosis type II (NF2) patients following implantation of a MED-EL COMBI 40+ auditory brainstem implant (ABI). Patients (n = 32) were enrolled postsurgically. Nonauditory side effects were evaluated at fitting and audiological performance was determined using the Sound Effects Recognition Test (SERT), Monosyllable-Trochee-Polysyllable (MTP) test and open-set sentence tests. Subjective benefits were determined by questionnaire. ABI activation was documented in 27 patients, 2 patients were too ill for testing and 3 patients were without any auditory perception. SERT and MTP outcomes under auditory-only conditions improved significantly between first fitting and 12-month follow-up. Open-set sentence recognition improved from 5% at first fitting to 37% after 12 months. The number of active electrodes had no significant effect on performance. All questionnaire respondents were 'satisfied' to 'very satisfied' with their ABI. An ABI is an effective treatment option in NF2 patients with the potential to provide open-set speech recognition and subjective benefits. To our knowledge, the data presented herein is exceptional in terms of the open-set speech perception achieved in NF2 patients.

Evaluation of vestibular and dynamic visual acuity in adults with congenital deafness.

This study compared vestibular and dynamic visual acuity in 19 adult athletes with deafness participating in Deaflympics to those of 25 young adults with normal hearing. Balance capability was evaluated using a one-leg standing test with eyes open and stabilometry. Caloric tests and vestibular evoked myogenic potential tests were conducted to test vestibular function. Visual function was evaluated using a dynamic visual acuity test. No significant difference was found between results of the one-leg standing test with eyes open and stabilometry with eyes open. Athletes with deafness performed better than normal hearing young adults with eyes closed. The caloric test indicated hypofunction of the lateral semicircular canal function in 5 of the 19 athletes with deafness. Balance-function tests showed normal results for both groups. The results for athletes with deafness on visual acuity were better than those of controls. Young Deaflympics athletes with deafness can adjust their balance function as well as or better than normal hearing young adults using dynamic visual acuity.

[Problem and assignment for distinguishing the Usher syndrome type].

Usher syndrome is an autosomal-recessive disorder that causes bilateral sensorineural hearing loss, retinitis pigmentosa (RP), and occasionally vestibular dysfunction. Usher syndrome types 1, 2, and 3 can be distinguished by differences in audiovestibular features. The objectives of this retrospective study were to evaluate 26 patients with Usher syndrome clinically. The 26 patients (male: 12 cases, female: 14 cases) with Usher syndrome, with a clinical diagnosis based on symptoms of bilateral sensorineural hearing loss and RP, had been registered from 13 hospitals as a multicenter study. We assessed the clinical history and performed audiovestibular and ophthalmologic examinations, and genetic testing. Eleven of the patients were classified as having Usher type 1 (38.5%), 6 with Usher type 2 (23.1%), and 9 with Usher type 3 (38.5%). However, many patients with atypical Usher type 1 (70%) and type 2 (83.3%) were found compared with Usher type 3 (10%). The conductive rate of vestibular examinations including the caloric test (50%) was low. There were many variations in the clinical symptoms in Usher syndrome patients, therefore the classification of Usher types 1, 2, and 3 has been complicated. We have proposed a flowchart for the diagnosis of Usher types 1, 2, and 3.

Comparison of vestibular ocular reflex and gross motor development in children with semicircular canal aplasia and hypoplasia.

OBJECTIVE: To examine the effect of vestibular ocular reflex on gross motor development in children with semicircular canal aplasia and hypoplasia. STUDY DESIGN: Case series. MATERIALS AND METHODS: Children with congenital hearing loss underwent temporal bone computed tomography to assess their inner ear morphology. In this study, we examined eight children with bilateral complete aplasia of semicircular canals and seven children with bilateral hypoplasia of semicircular canals. Their vestibular ocular reflex was assessed using a damped rotational chair test. Their gross motor development was assessed by examining their ages of acquisition of head control and independent walking. RESULTS: All eight children with semicircular canal aplasia were diagnosed as having CHARGE syndrome and five children were found to have CHD7 mutations. Cochlear morphological examination showed that cochlear hypoplasia type III was the most common in eight of 16 ears in children with semicircular canal aplasia. In semicircular canal hypoplasia, incomplete partition type II was found in seven of 14 ears. All eight children with semicircular canal aplasia showed no response in the damped rotational chair test. Even the three children followed up were unresponsive in all tests. In the group with semicircular canal hypoplasia, three children showed normal responses, one child showed no response, and three children showed poor responses. The mean age of acquisition of head control was 9.1 ± 6.3 months and that of independent walking was 31 ± 8.1 months in children with semicircular canal aplasia. The mean age of acquisition of head control was 6.0 ± 2.8 months and that of independent walking was 19.9 ± 4.9 months in children with semicircular canal hypoplasia. CONCLUSIONS: We found that children with semicircular canal aplasia have severe dysfunction of the vestibular ocular reflex, and vestibular sensory cells derived from the semicircular canal may not be present. Semicircular canal hypoplasia is associated with dysfunction of the vestibular ocular reflex, but vestibular sensory cells may be present, and rotary nystagmus develops with growth similar to that observed in normal children previously reported. Semicircular canal aplasia is associated with CHARGE syndrome, and affected children tended to have a slower gross motor development. It was suggested that the combination of visual impairment and mental retardation may delay the development of central-level integrated functions and may further delay motor development.

Efficacy of transtympanic infusion of dexamethasone into the tympanic cavity in mice with acute sensorineural hearing loss associated with cytomegalovirus infection.

BACKGROUND: There is no report on acute sensorineural hearing loss with congenital cytomegalovirus (cCMV) infection in basic experiments. AIMS/OBJECTIVES: The aim of this study was to evaluate the effect of dexamethasone, an anti-inflammatory steroid, on acute sensorineural hearing loss in the mouse cytomegalovirus (MCMV) infection model mice. MATERIAL AND METHODS: Sensorineural hearing loss model mice were divided into two groups, one with and one without intratympanic dexamethasone. Dexamethasone was injected into the tympanic cavity of only the right ear, and hearing ability was assessed at the ages of three, six, and eight weeks by auditory brainstem response measurement. RESULTS: Among the 23 mice intratympanically injected with dexamethasone (15 µg/mouse) at the age of three weeks, five (21.7%) had a hearing improvement of at least 10 dB and 18 (78.3%) had no improvement at the age of six weeks. Among the 19 mice that did not receive a dexamethasone injection, one (5.3%) showed improvement and 18 (94.7%) showed no improvement (p = 0.129). CONCLUSIONS AND SIGNIFICANCE: In this study, transtympanic infusion of dexamethasone into the tympanic cavity was effective in some mice with sensorineural hearing loss, suggesting that, in addition to angiogenesis, anti-inflammatory activity might be a mechanism of treatment for hearing loss.

Cervical vestibular evoked myogenic potentials in 3-month-old infants: Comparative characteristics and feasibility for infant vestibular screening.

Objective: We compared the characteristics of air-conducted sound cervical vestibular evoked myogenic potential (ACS-cVEMP) and bone-conducted vibration cVEMP (BCV-cVEMP) among 3-month-old infants with normal hearing and sensorineural hearing loss (SNHL), and healthy adults to explore the feasibility and optimal strategies for infant vestibular screening. Methods: 29 infants (58 ears) were divided into two groups according to hearing (group I: normal hearing ears; group II: SNHL ears), 20 healthy adults were defined as group III. The results of response rate, P13 and N23 latency, P13-N23 interval, amplitudes, and corrected interaural asymmetry ratio (IAR) were recorded and compared among three groups. Results: The response rates of ACS-cVEMP in three groups were 88.89, 62.00, 100%, respectively. The P13 and N23 latencies, and P13-N23 interval did not differ significantly between group I and II (p = 0.866, p = 0.190, p = 0.252). A significant difference was found between group I and III (p = 0.016, p < 0.001, p < 0.001). No significant difference was observed in raw or corrected amplitude between group I and II (p = 0.741, p = 0.525), while raw and corrected amplitudes in group III were significantly larger than group I (p < 0.001, p < 0.001). For BCV-cVEMP, the response rates in three groups were 100, 86.36, 100%, respectively, No significant difference existed in the P13 and N23 latency, or P13-N23 interval between group I and II (p = 0.665, p = 0.925, p = 0.806), however, P13 and N23 latencies were significantly longer in group III than group I (p < 0.001, p = 0.018), but not in P13-N23 interval (p = 0.110). There was no significant difference in raw or corrected amplitude between group I and II (p = 0.771, p = 0.155) or in raw amplitude between group I and III (p = 0.093), however, a significant difference existed in corrected amplitude between group I and III (p < 0.001). Conclusions: Compared with adults, 3-month-old infants with normal hearing presented with equivalent response rates, shorter P13 and N23 latencies, smaller corrected amplitudes, and a wider IAR range for both ACS and BCV-cVEMP. SNHL infants had equivalent response rates of BCV-cVEMP, lower response rates of ACS-cVEMP than normal hearing infants. When responses were present, characteristics of ACS and BCV-cVEMP in SNHL infants were similar with normal hearing infants. ACS combined with BCV-cVEMP are recommended to improve the accuracy of vestibular screening.

Acoustic overstimulation-induced apoptosis in fibrocytes of the cochlear spiral limbus of mice.

Fibrocytes of the spiral limbus are thought to play a significant role in maintaining ion homeostasis in the cochlea. The present study measured physiological and morphological changes in spiral limbus of mice in response to noise exposure. 6-week-old male C3H/HeJJcl mice were exposed to octave-band noise (120 dB SPL) for 2 h and evaluated at a series of times thereafter, up to 8 weeks. Permanent hearing loss resulted in the mice, as assessed by auditory brainstem response (ABR) recordings. The fibrocytes loss was found in the spiral limbus of the apical turn, which has been proved to be induced by apoptosis. These results suggest that noise exposure might result in apoptosis of fibrocytes in spiral limbus, which suggest a mechanism for noise-induced hearing loss.

Charcot-Marie-Tooth Disease With Long-Term Follow-Up on Auditory Neuropathy-After Cochlear Implantation Or Hearing Aid Use.

OBJECTIVE: To study the pathophysiology of Charcot-Marie-Tooth disease (CMT) with auditory neuropathy (AN) and to follow up cochlear implant or hearing aid use over the long term. STUDY DESIGN: Clinical capsule report. PATIENTS: Two adult CMT patients with AN. INTERVENTION: Cochlear implantation for case 1 and hearing aid use for case 2. RESULT: Case 1 was a 50-year-old man who was diagnosed as having CMT at 15 years of age. He noted his hearing impairment at the age of 22. We considered that he had AN as a complication on the basis of the findings of normal distortion product otoacoustic emission and the absence of auditory brainstem response on both ears. We performed cochlear implantation for his progressive hearing loss when he was 41 years old. His postoperative discrimination scores for words and sentences in the CI-2004 test 4 years after cochlear implantation were 80% and 93%, respectively. His sound discrimination scores were 23/24 in the test with picture matching and 9/24 in that without picture matching 8 years after cochlear implantation.Case 2 was a 38-year-old woman who was neurologically diagnosed as having CMT with AN as a complication on the basis of auditory brainstem response and distortion product otoacoustic emission test findings. During 15 years of follow-up, her discrimination score decreased gradually. She is currently wearing a hearing aid. CONCLUSIONS: We found a significant improvement in case 1 and a slight increase in hearing level in case 2. The pathoneurological findings of CMT might be either demyelination or axonal degeneration depending on the type of genetic abnormality (e.g., PMP22 and MPZ mutations). The symptoms and courses vary among patients with CMT. Therefore, the selection of an appropriate intervention for hearing loss depending on the severity and course is very important.

Patterns of hearing changes in women and men from denarians to nonagenarians.

BACKGROUND: Hearing loss needs to be diagnosed and treated early, especially in older individuals, since presbycusis potentially increases the risk of depression and dementia. However, standard data on hearing thresholds across the life-span in Japanese individuals are lacking. METHODS: In a retrospective consecutive sample of 10681 native-Japanese speakers (37.3% men; 10-99 years; left-right hearing threshold difference of <15 dB for all tested pure tones; free of external, middle, or inner ear disease), we determined standard age-decade and sex-specific pure-tone air-conduction (125, 250, 500, 1000, 2000, 4000, and 8000 Hz) hearing threshold norms. The main outcome measures were pure-tone averages for both ears by age-decade and sex. FINDINGS: For participants in their 20s, hearing thresholds at higher frequencies (>1000 Hz) were significantly worse in men than in women. For participants ≥70 years, hearing thresholds at low frequencies were higher in women. Hearing thresholds at 1000, 2000, and 4000 Hz tended to deteriorate, starting in the teenage years through the 50s, with some decades showing significantly worse decline. Sex differences were absent in the youngest and oldest groups. INTERPRETATION: Standard age- and sex-specific audiometric data reported here for Japanese individuals over nine age-decades are based on the largest dataset analyzed to date. While hearing thresholds of men and women in the very young and the very old age groups were indistinguishable in their cohorts, patterns of hearing changes for other age cohorts differed by direction and sex. FUNDING: The authors had no outside funding for this study.

Subcortical deafness as a subtype of auditory agnosia after injury of bilateral auditory radiations caused by two cerebrovascular accidents - normal auditory brainstem responses with I-VII waves and abolished consciousness of hearing.

BACKGROUND: In central auditory disorders caused by damage of the cerebral hemispheres, there are cortical deafness and auditory agnosia. Although clinical cases of cortical deafness have been reported, little is known about the hearing problems and localized lesions associated with cortical deafness. AIMS/OBJECTIVES: The aims of our research are to elucidate lesion sites associated with cortical deafness and to clarify why patients with cerebral lesions are not aware of any sound at all. MATERIALS AND METHODS: Three patients diagnosed as having total loss of hearing participated in this study. We conducted pure-tone audiometry, speech audiometry, distortion product otoacoustic emission (DPOAE), auditory brainstem response (ABR), and brain magnetic resonance imaging (MRI) to diagnose cortical deafness with aphasia tests of these patients. RESULTS: Our studies showed that waves VI and VII as well as waves I to V have normal peak latencies in ABRs in all three patients. In brain MRI, we found complete damage of proximal parts of bilateral auditory radiations in the three patients. CONCLUSIONS: We propose 'subcortical deafness' as a subtype of auditory agnosia.

EABR measurements during cochlear implantation in one-year-old, infant, child, adult, and elderly patients.

BACKGROUND: Clinical application of electrically-evoked intracochlear auditory brainstem responses (eABRs) for evaluation of brainstem maturity or aging changes has not been well investigated. AIM/OBJECTIVE: We compare the eV latencies of intraoperative eABR measurements in one-year-olds, infants, children, adults, and the elderly, with the goal of investigating the changes in the brainstem auditory pathway due to development and aging. MATERIALS AND METHODS: We studied 58 ears of 51 patients who underwent cochlear implantation between 2013 and 2019 using MED-EL's Concerto or Synchrony implants with Flex28 or Flex soft electrodes. EABRs were recorded during cochlear implantation. The stimuli were delivered by the MED-EL Maestro to the apical, middle, and basal turn electrodes at stimulus levels 1000, 800, and 600 cu, with a pulse width of 30 µs. RESULTS: In eABRs recorded from electrodes installed at both the mastoid and nape, there was no difference in latency between age groups within each stimulus level. CONCLUSION AND SIGNIFICANCE: ABR latency was not affected by development after age one and aging of the brainstem auditory pathway. Our study will be useful as a control in identifying abnormal eABR wave configurations in patients with cochlear malformations, cochlear nerve deficiencies, or auditory neuropathy, regardless of age.

Cochlear Implantation in Cases of Inner Ear Malformation: A Novel and Simple Grading, Intracochlear EABR, and Outcomes of Hearing.

OBJECTIVE: To propose a simple grading of inner ear malformation (IEM) and investigate intracochlear electrical auditory brainstem response (EABR) and outcomes for hearing in terms of the novel grading system. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Sixty patients with IEMs who received cochlear implants. INTERVENTION: Grading according to observation of modiolus deficiency and/or internal auditory canal (IAC) cochlear nerve deficiency (CND). MAIN OUTCOME MEASURE: Intracochlear EABR and categories of auditory performance (CAP) scores were assessed; children in school were categorized according to the type of school attended. RESULTS: Among 60 patients, 38% were classified as Grade I (modiolus present + normal cochlear nerve), 22% as grade II (modiolus deficiency + normal cochlear nerve), 33% as grade III (modiolus present + IAC CND), and 7% as grade IV (modiolus deficiency + IAC CND). During the operation, 93% of Grade I, 36% of Grade II, 23% of Grade III, and 50% of Grade IV patients showed typical EABR waves. CAP scores of 4 or more were obtained from 91% of Grade I, 62% of Grade II, 35% of Grade III, and 25% of Grade IV. Whereas none of children in Grades III and IV entered main stream school, 55% of Grade I and 25% of Grade II entered mainstream schools. CONCLUSIONS: Outcomes of hearing with cochlear implantations in IEM children depend on the severity of IEM and IAC CND. Our novel grading of IEM is simple and can be useful for understanding the severity of IEM.