Electrically Evoked Auditory Potentials Recorded at Three Levels of the Auditory Pathway From Multichannel Cochlear Implant Subjects: Characterization and Comparison to Behavioral Measures

Abstract

Results of varied stimulus levels and implanted electrode sites were used to characterize the electrophysiologic responses of the EABR, EAMLR, and ELAR with regard to latency, amplitude and evoked potential thresholds (EPT). Comparisons between the EPTs and behavioral measures suggest that thresholds of either the Wave V, the Na-Pa complex, or the N1-P2 complex may be used to select stimulus levels that are audible for subjects, although the location of the EPT within the behavioral dynamic range varied across subjects. The poorest performers on measures of speech recognition had the smallest behavioral dynamic range (BDR) and the smallest BDR difference scores (difference in BDR at the fastest rate compared to the slowest rate). Of the evoked potentials studied, the EAMLR was the most closely associated with better speech perception performance based on measures of normalized amplitude and evoked potential threshold.