The relationship between EAP and EABR thresholds and levels used to program the nucleus 24 speech processor: data...

Area of Science:

• Audiology
• Biomedical Engineering
• Neuroscience

Background:

• Cochlear implant programming relies on behavioral thresholds (T-level and C-level).
• Physiological measures like EAP and EABR offer objective data.
• Accurate programming is crucial for effective cochlear implant function.

Purpose of the Study:

• To investigate the relationship between EAP and EABR thresholds and T- and C-levels in Nucleus 24 cochlear implant users.
• To assess the accuracy of predicting T- and C-levels using physiological measures.
• To explore methods for improving prediction accuracy.

Main Methods:

• Recruited 44 adult Nucleus 24 cochlear implant users.
• Measured EAP thresholds using Neural Response Telemetry.
• Measured EABR thresholds in 14 subjects using standard evoked potential techniques.
• Compared physiological thresholds with behavioral T- and C-levels across multiple electrodes.

Main Results:

• EAP thresholds showed a weak correlation with T- and C-levels.
• A technique combining EAP thresholds with T- and C-level data improved prediction accuracy (r=0.83 for T-level, r=0.77 for C-level).
• EABR thresholds yielded similar predictive accuracy and were generally lower than EAP thresholds.

Conclusions:

• EAP and EABR thresholds can be used with limited behavioral data to predict cochlear implant programming levels.
• Physiological measures offer a valuable adjunct to behavioral testing for programming.
• These findings support objective measures in optimizing cochlear implant fitting.