Speech Recognition Materials and Ceiling Effects: Considerations for Cochlear Implant Programs

TLDR

Cochlear implant recipients have shown marked speech perception gains since FDA approval in 1984, driven by advances in technology, coding strategies, and increased residual hearing, yet pre‑ and postimplant testing recommendations have remained unchanged for over a decade. The study aimed to evaluate whether updated speech recognition testing recommendations are needed for cochlear implant patients. The authors assessed speech perception in 156 postlingually deafened implant recipients and 50 hearing aid users using monosyllabic word recognition (CNC) and sentence recognition in quiet (HINT and AzBio) and in noise (BKB‑SIN). Results showed that 28 % of implant recipients achieved perfect scores on HINT sentences in quiet, but only 0.7 % did so on AzBio sentences, and overall AzBio performance correlated better with monosyllabic and noisy sentence scores, indicating that more challenging materials are required to evaluate post‑implant speech perception and candidacy.

Abstract

Cochlear implant recipients have demonstrated remarkable increases in speech perception since US FDA approval was granted in 1984. Improved performance is due to a number of factors including improved cochlear implant technology, evolving speech coding strategies, and individuals with increasingly more residual hearing receiving implants. Despite this evolution, the same recommendations for pre- and postimplant speech recognition testing have been in place for over 10 years in the United States. To determine whether new recommendations are warranted, speech perception performance was assessed for 156 adult, postlingually deafened implant recipients as well as 50 hearing aid users on monosyllabic word recognition (CNC) and sentence recognition in quiet (HINT and AzBio sentences) and in noise (BKB-SIN). Results demonstrated that for HINT sentences in quiet, 28% of the subjects tested achieved maximum performance of 100% correct and that scores did not agree well with monosyllables (CNC) or sentence recognition in noise (BKB-SIN). For a more difficult sentence recognition material (AzBio), only 0.7% of the subjects achieved 100% performance and scores were in much better agreement with monosyllables and sentence recognition in noise. These results suggest that more difficult materials are needed to assess speech perception performance of postimplant patients - and perhaps also for determining implant candidacy.