Within-electrode temporal envelope processing predicts multi-channel speech outcomes across cochlear implant pulse
Biorxiv : the Preprint Server for Biology
|July 10, 2026
Summary
Cochlear implants (CIs) performance depends on stimulation pulse rate. Lower rates impair hearing cues, while higher rates show listener-specific effects, impacting speech understanding.
Area of Science:
- Neuroscience
- Audiology
- Biomedical Engineering
Background:
- Cochlear implants (CIs) restore hearing by stimulating auditory neurons.
- Effective speech recognition relies on processing amplitude envelopes across frequency bands.
Purpose of the Study:
- To investigate how stimulation pulse rate affects temporal envelope processing and speech cue perception in post-lingually deaf CI users.
- To evaluate amplitude modulation (AM) detection and consonant identification across various pulse rates.
Main Methods:
- Assessed AM detection thresholds and consonant identification in ten CI users.
- Utilized standard clinical multi-channel and single-channel strategies.
- Examined pulse rate effects ranging from 125 to 4000 pulses per second (pps).
Main Results:
- Performance significantly declined at 125 pps, indicating perceptual limits rather than sampling issues.
- AM detection showed a non-significant reduction at 4000 pps.
- Consonant recognition was stable between 250-2000 pps, with individual variations observed.
- Strong correlations between single-channel and multi-channel performance were found.
Conclusions:
- Within-electrode temporal envelope processing significantly contributes to multi-channel speech perception.
- Individual variability in pulse rate effects is clinically relevant for CI users.
- Stimulation pulse rate is a critical factor influencing CI efficacy.