High-Variability Sentence Recognition in Long-Term Cochlear Implant Users: Associations With Rapid Phonological...

Area of Science:

• Neuroscience
• Audiology
• Cognitive Psychology

Background:

• Cochlear implants (CI) are sophisticated devices for hearing restoration.
• Understanding the cognitive demands of speech processing in CI users is crucial.
• Long-term CI use may impact phonological coding and executive functions (EF).

Purpose of the Study:

• To compare rapid phonological coding and EF reliance between long-term CI users and normal-hearing (NH) peers.
• To investigate the association between phonological coding, EF, and sentence recognition in challenging listening conditions.
• To test hypotheses regarding CI users' performance on high-variability speech tasks.

Main Methods:

• Cross-sectional study of 49 long-term CI users and 56 NH individuals (ages 9-29).
• Utilized tests for rapid phonological coding (nonword repetition), conventional sentence recognition, and high-variability sentence recognition.
• Assessed executive functions including verbal working memory, cognitive fluency, and inhibition.

Main Results:

• CI users performed significantly worse on high-variability sentence recognition than NH peers, even after controlling for basic recognition skills.
• Stronger correlations between rapid phonological coding and high-variability sentence recognition were observed in CI users compared to NH peers.
• While direct EF correlations were not significant after correction, verbal working memory showed potential links to sentence recognition in CI users.

Conclusions:

• Findings support dual-channel speech processing models, highlighting a fast-automatic channel and a compensatory slow-effortful channel.
• CI users demonstrate greater reliance on rapid phonological coding for challenging speech perception.
• Further research into verbal working memory in CI users is recommended for clinical insights.