Auditory, Visual, and Cognitive Abilities in Normal-Hearing Adults, Hearing Aid Users, and Cochlear Implant Users.

OBJECTIVES: Speech understanding is considered a bimodal and bidirectional process, whereby visual information (i.e., speechreading) and also cognitive functions (i.e., top-down processes) are involved. Therefore, the purpose of the present study is twofold: (1) to investigate the auditory (A), visual (V), and cognitive (C) abilities in normal-hearing individuals, hearing aid (HA) users, and cochlear implant (CI) users, and (2) to determine an auditory, visual, cognitive (AVC)-profile providing a comprehensive overview of a person's speech processing abilities, containing a broader variety of factors involved in speech understanding. DESIGN: Three matched groups of subjects participated in this study: (1) 31 normal-hearing adults (mean age = 58.76), (2) 31 adults with moderate to severe hearing loss using HAs (mean age = 59.31), (3) 31 adults with a severe to profound hearing loss using a CI (mean age = 58.86). The audiological assessments consisted of pure-tone audiometry, speech audiometry in quiet and in noise. For evaluation of the (audio-) visual speech processing abilities, the Test for (Audio) Visual Speech perception was used. The cognitive test battery consisted of the letter-number sequencing task, the letter detection test, and an auditory Stroop test, measuring working memory and processing speed, selective attention, and cognitive flexibility and inhibition, respectively. Differences between the three groups were examined using a one-way analysis of variance or Kruskal-Wallis test, depending on the normality of the variables. Furthermore, a principal component analysis was conducted to determine the AVC-profile. RESULTS: Normal-hearing individuals scored better for both auditory, and cognitive abilities compared to HA users and CI users, listening in a best aided condition. No significant differences were found for speech understanding in a visual condition, despite a larger audiovisual gain for the HA users and CI users. Furthermore, an AVC-profile was composed based on the different auditory, visual, and cognitive assessments. On the basis of that profile, it is possible to determine one comprehensive score for auditory, visual, and cognitive functioning. In the future, these scores could be used in auditory rehabilitation to determine specific strengths and weaknesses per individual patient for the different abilities related to the process of speech understanding in daily life. CONCLUSIONS: It is suggested to evaluate individuals with hearing loss from a broader perspective, considering more than only the typical auditory abilities. Also, cognitive and visual abilities are important to take into account to have a more complete overview of the speech understanding abilities in daily life.

Dual-Task Interference in the Assessment of Listening Effort: Results of Normal-Hearing Adults, Cochlear Implant Users, and Hearing Aid Users.

PURPOSE: The purpose of the current study was to assess dual-task interference (i.e., changes between the dual-task and baseline condition) in a listening effort dual-task paradigm in normal-hearing (NH) adults, hearing aid (HA) users, and cochlear implant (CI) users. METHOD: Three groups of 31 participants were included: (a) NH adults, (b) HA users, and (c) CI users. The dual-task paradigm consisted of a primary speech understanding task in a quiet condition, and a favorable and unfavorable noise condition, and a secondary visual memory task. Dual-task interference was calculated for both tasks, and participants were classified based on their patterns of interference. Descriptive analyses were established and differences between the three groups were examined. RESULTS: The descriptive results showed varying patterns of dual-task interference between the three listening conditions. Most participants showed the pattern of visual memory interference (i.e., worse results for the secondary task in the dual-task condition and no difference for the primary task) in the quiet condition, whereas the pattern of speech understanding priority trade-off (i.e., worse results for the secondary task in the dual-task condition and better results for the primary task) was most prominent in the unfavorable noise condition. Particularly, in HA and CI users, this shift was seen. However, the patterns of dual-task interference were not statistically different between the three groups. CONCLUSIONS: Results of this study may provide additional insight into the interpretation of dual-task paradigms for measuring listening effort in diverse participant groups. It highlights the importance of considering both the primary and secondary tasks for accurate interpretation of results. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.26409088.

Cochlear Implantation in Single-Sided Deafness and Asymmetric Hearing Loss: 12 Months Follow-up Results of a European Multicenter Evaluation.

People with single-sided deafness (SSD) or asymmetric hearing loss (AHL) have particular difficulty understanding speech in noisy listening situations and in sound localization. The objective of this multicenter study is to evaluate the effect of a cochlear implant (CI) in adults with single-sided deafness (SSD) or asymmetric hearing loss (AHL), particularly regarding sound localization and speech intelligibility with additional interest in electric-acoustic pitch matching. A prospective longitudinal study at 7 European tertiary referral centers was conducted including 19 SSD and 16 AHL subjects undergoing cochlear implantation. Sound localization accuracy was investigated in terms of root mean square error and signed bias before and after implantation. Speech recognition in quiet and speech reception thresholds in noise for several spatial configurations were assessed preoperatively and at several post-activation time points. Pitch perception with CI was tracked using pitch matching. Data up to 12 months post activation were collected. In both SSD and AHL subjects, CI significantly improved sound localization for sound sources on the implant side, and thus overall sound localization. Speech recognition in quiet with the implant ear improved significantly. In noise, a significant head shadow effect was found for SSD subjects only. However, the evaluation of AHL subjects was limited by the small sample size. No uniform development of pitch perception with the implant ear was observed. The benefits shown in this study confirm and expand the existing body of evidence for the effectiveness of CI in SSD and AHL. Particularly, improved localization was shown to result from increased localization accuracy on the implant side.