Audio-visual integration during speech perception in prelingually deafened Japanese children revealed by the McGurk effect.

OBJECTIVE: To investigate the McGurk effect in profoundly deafened Japanese children with cochlear implants (CI) and in normal-hearing children. This was done to identify how children with profound deafness using CI established audiovisual integration during the speech acquisition period. METHODS: Twenty-four prelingually deafened children with CI and 12 age-matched normal-hearing children participated in this study. Responses to audiovisual stimuli were compared between deafened and normal-hearing controls. Additionally, responses of the children with CI younger than 6 years of age were compared with those of the children with CI at least 6 years of age at the time of the test. RESULTS: Responses to stimuli combining auditory labials and visual non-labials were significantly different between deafened children with CI and normal-hearing controls (p<0.05). Additionally, the McGurk effect tended to be more induced in deafened children older than 6 years of age than in their younger counterparts. CONCLUSIONS: The McGurk effect was more significantly induced in prelingually deafened Japanese children with CI than in normal-hearing, age-matched Japanese children. Despite having good speech-perception skills and auditory input through their CI, from early childhood, deafened children may use more visual information in speech perception than normal-hearing children. As children using CI need to communicate based on insufficient speech signals coded by CI, additional activities of higher-order brain function may be necessary to compensate for the incomplete auditory input. This study provided information on the influence of deafness on the development of audiovisual integration related to speech, which could contribute to our further understanding of the strategies used in spoken language communication by prelingually deafened children.

Electrically evoked auditory brainstem response-based evaluation of the spatial distribution of auditory neuronal tissue in common cavity deformities.

OBJECTIVE: In a common cavity (CC) deformity, the cochlea and vestibule are confluent to form a single cavity without internal architecture, and distribution of auditory neuronal tissue is unclear. The purposes of this study are to reveal the spatial distribution of auditory neuronal tissue in CC deformity using electrically evoked auditory brainstem response (EABR) during cochlear implantation. STUDY DESIGN: Retrospective case review. SETTING: Cochlear implant (CI) center at a tertiary referral hospital. PATIENTS: Five patients with CC deformity who underwent cochlear implantation and intraoperative EABR testing. MAIN OUTCOME MEASURES: Spatial distribution of electrodes that elicited an evoked wave V (eV) in EABR testing was evaluated in each CC deformity. RESULTS: Electrically evoked auditory brainstem response testing demonstrated that electrodes attached on the inner wall of the anteroinferior cavity of the CC deformity successfully elicited a reproducible eV in all cases, and the latency of each eV was an approximately 4 ms, which is similar to those reported in patients without an inner ear malformation. Interestingly, in Case 1 with the lowest percentage of eV-positive electrodes (31.8%), CI-aided audiometric thresholds were changed, depending on the frequency allocation to eV-positive electrodes in the programming. Cochlear implant-mediated facial nerve stimulation was observed in 3 of 5 cases, and results of EABR testing were useful for optimizing the device program to decrease facial nerve stimulation without sacrificing CI-mediated auditory performance. CONCLUSION: The results of EABR testing suggested that auditory neuronal elements are distributed to the anteroinferior part of CC deformity, mainly around or near the inner wall of the cavity. In cases with CC deformity, EABR testing is useful to achieve the optimal electrode array placement and to adjust programming parameters of the implanted device, which might be essential to maximize CI outcomes and to decrease facial nerve stimulation.

Cochlear implantation in children with congenital cytomegalovirus infection accompanied by psycho-neurological disorders.

CONCLUSION: Cochlear implantation was effective for deaf children with congenital cytomegalovirus (CMV) infection, but their cochlear implant (CI) outcomes were often impaired, depending on the types of CMV-associated psycho-neurological disorders. Evaluation of cognitive development and autistic tendency of implantees might be useful to predict their CI outcomes. OBJECTIVES: To reveal the influence of CMV-associated psycho-neurological disorders on CI outcomes. METHODS: This was a retrospective evaluation of 11 implantees with congenital CMV infection (CMV-CIs) and 14 implantees with autosomal recessive hearing loss (genetic-CIs). RESULTS: Nine of 11 CMV-CIs suffered from psycho-neurological disorders; one from attention deficit hyperactivity disorder, two from pervasive developmental disorder, and six from mental retardation. Aided hearing thresholds with CIs in the two groups did not differ, but two autistic and two mentally retarded CMV-CIs showed significantly low scores in speech discrimination tests. Language-Social (L-S) developmental quotients (DQs) evaluated by the Kyoto Scale of Psychological development were improved after the implantation in both groups, but the postoperative increase of L-S DQs was significantly smaller in the CMV-CIs than that of genetic-CIs. Interestingly, the postoperative L-S and Cognitive-Adaptive (C-A) DQs showed statistically significant correlation in all cases except for two autistic CMV-CIs whose L-S DQs were much lower than those expected from their C-A DQs.