Engaging effort improves efficiency during spoken word recognition in cochlear implant users

Area of Science:

• Auditory Neuroscience
• Speech Perception
• Human-Computer Interaction

Background:

• Word recognition relies on lexical competition, which is altered by challenging listening conditions like noise or hearing loss.
• In cochlear implant (CI) users, lexical competition dynamics (timing, resolution, activation rate) are affected, leading to listening effort.
• The relationship between specific lexical competition dimensions and listening effort in CI users remains unclear.

Purpose of the Study:

• To investigate the relationship between dimensions of lexical competition and listening effort in cochlear implant users.
• To determine how effort magnitude and timing relate to word recognition outcomes in this population.

Main Methods:

• Seventy-nine cochlear implant users participated in the study.
• Pupillometry was used to measure listening effort (peak pupil size difference).
• The Visual World Paradigm assessed lexical competition dynamics (Wait-and-See, Sustained Activation, Activation Rate).

Main Results:

• Higher listening effort (greater peak pupil size) correlated with a lower 'Wait-and-See' score, indicating earlier lexical competition onset.
• Earlier engagement of listening effort predicted better word and sentence recognition.
• Age and spectral fidelity predicted the timing of effort, but not its magnitude.

Conclusions:

• The timing of lexical competition, influenced by effort, is crucial for successful word recognition in cochlear implant users.
• A dissociation exists between the magnitude and timing of listening effort, suggesting distinct roles in speech processing.
• Effort timing, influenced by factors like age and acoustic conditions, is a key predictor of auditory performance in CI users.