Extraordinary Speech and Language Outcomes After Auditory Brainstem Implantation: Guidance From a Case Study.

PURPOSE: Large individual differences and poor speech recognition outcomes are routinely observed in most patients who have received auditory brainstem implants (ABIs). A case report of an ABI recipient with exceptionally good speech recognition outcomes presents an opportunity to better understand the core information processing mechanisms that underlie variability and individual differences in outcomes. METHOD: A case study is reported of an adult ABI recipient (ID-006) with postlingually acquired, Neurofibromatosis Type 2 (NF2)-related hearing loss who displayed exceptional postoperative speech recognition scores. A novel battery of assessment measures was used to evaluate ID-006's auditory, cognitive, and linguistic information processing skills. RESULTS: Seventeen years following ABI activation, ID-006 scored 77.6% correct on the AzBio Sentences in quiet. On auditory processing tasks, ID-006 scored higher on tasks with meaningful sentences and much lower on tasks that relied exclusively on audibility. ID-006 also demonstrated exceptionally strong abilities on several cognitive and linguistic information processing tasks. CONCLUSIONS: Results from a novel battery of information processing tests suggest that ID-006 relies extensively on top-down predictive processing and cognitive control strategies to efficiently encode and process auditory information provided by his ABI. Results suggest that current measures of outcomes and benefits should be expanded beyond conventional speech recognition measures to include more sensitive and robust measures of speech recognition as well as neurocognitive measures such as executive function, working memory, and lexical access.

Speed of Information Processing and Verbal Working Memory in Children and Adolescents With Cochlear Implants.

BACKGROUND: Verbal working memory delays are found in many deaf children with cochlear implants compared with normal-hearing peers, but the factors contributing to these delays are not well understood. This study investigated differences between cochlear implant users and normal-hearing peers in memory scanning speed during a challenging verbal working memory task. To better understand variability in verbal working memory capacity within each sample, associations between memory scanning speed, speech recognition, and language were also investigated. METHODS: Twenty-five prelingually deaf, early implanted children (age, 8-17 yr) with cochlear implants and 25 normal-hearing peers completed the Wechsler Intelligence Scale for Children, Fifth Edition, Letter-Number Sequencing (LNS) working memory task. Timing measures were made for response latency and average pause duration between letters/numbers recalled during the task. Participants also completed measures of speech recognition, vocabulary, and language comprehension. RESULTS: Children with cochlear implants had longer pause durations than normal-hearing peers during three-span LNS sequences, but the groups did not differ in response latencies or in pause durations during two-span LNS sequences. In the sample of cochlear implant users, poorer speech recognition was correlated with longer pause durations during two-span sequences, whereas poorer vocabulary and weaker language comprehension were correlated with longer response latencies during two-span sequences. Response latencies and pause durations were unrelated to language in the normal-hearing sample. CONCLUSION: Children with cochlear implants have slower verbal working memory scanning speed than children with normal hearing. More robust phonological-lexical representations of language in memory may facilitate faster memory scanning speed and better working memory in cochlear implant users.

Exceptional Speech Recognition Outcomes After Cochlear Implantation: Lessons From Two Case Studies.

PURPOSE: Individual differences and variability in outcomes following cochlear implantation (CI) in patients with hearing loss remain significant unresolved clinical problems. Case reports of specific individuals allow for detailed examination of the information processing mechanisms underlying variability in outcomes. Two adults who displayed exceptionally good postoperative CI outcomes shortly after activation were administered a novel battery of auditory, speech recognition, and neurocognitive processing tests. METHOD: A case study of two adult CI recipients with postlingually acquired hearing loss who displayed excellent postoperative speech recognition scores within 3 months of initial activation. Preoperative City University of New York sentence testing and a postoperative battery of sensitive speech recognition tests were combined with auditory and visual neurocognitive information processing tests to uncover their strengths, weaknesses, and milestones. RESULTS: Preactivation CUNY auditory-only (A) scores were < 5% correct while the auditory + visual (A + V) scores were > 74%. Acoustically with their CIs, both participants' scores on speech recognition, environmental sound identification and speech in noise tests exceeded average CI users scores by 1-2 standard deviations. On nonacoustic visual measures of language and neurocognitive functioning, both participants achieved above average scores compared with normal hearing adults in vocabulary knowledge, rapid phonological coding of visually presented words and nonwords, verbal working memory, and executive functioning. CONCLUSIONS: Measures of multisensory (A + V) speech recognition and visual neurocognitive functioning were associated with excellent speech recognition outcomes in two postlingual adult CI recipients. These neurocognitive information processing domains may underlie the exceptional speech recognition performance of these two patients and offer new directions for research explaining variability in postimplant outcomes. Results further suggest that current clinical outcome measures should be expanded beyond the conventional speech recognition measures to include more sensitive robust tests of speech recognition as well as neurocognitive measures of working memory, vocabulary, lexical access, and executive functioning.

Remote Assessment of Verbal Memory in Youth With Cochlear Implants During the COVID-19 Pandemic.

Purpose Youth with cochlear implants (CIs) are at risk for delays in verbal short-term memory (STM)/working memory (WM), which adversely affect language, neurocognitive, and behavioral outcomes. Assessment of verbal STM/WM is critical for identifying and addressing these delays, but standard assessment procedures require face-to-face (FTF) administration. The purpose of this study was to determine the feasibility and validity of remote testing methods (teleassessment) of verbal STM/WM in youth with CIs as a method of addressing COVID-19-related restrictions on FTF test administration. Method Tests of verbal STM/WM for nonwords, digit spans, letter-number sequences, sentences, and stories were individually administered by speech-language pathologists over a teleassessment platform to 28 youth (aged 9-22 years) with CIs and 36 same-aged normal-hearing peers. Examiners, parents, and participants completed quality and satisfaction ratings with the teleassessment procedure. Teleassessment scores were compared to results of tests obtained at FTF visits an average of 1.6 years earlier. Results Quality and satisfaction ratings for teleassessment were high and in almost all cases did not differ between the CI and normal-hearing samples. Youth with CIs scored lower than normal-hearing peers on measures of verbal STM/WM, and scores for digit span and letter-number sequencing did not differbetween teleassessment and FTF methods. Correlations across teleassessment and FTF visits were strong for digit span, letter-number sequencing, and sentence memory, but were more modest for nonword repetition. Conclusion With some caveats, teleassessment of verbal STM/WM was feasible and valid for youth with CIs.