Pulse rate matching by cochlear implant patients: effects of loudness randomization and electrode position
1Department of Audiology, St. Paul's Hospital, Vancouver, British Columbia, Canada.
Objective:
To assess the accuracy with which cochlear implant patients are able to match two stimuli on the basis of pulse rate pitch.
Design:
Patients were required to adjust the pulse rate of a comparison stimulus to match that of a fixed reference stimulus. The comparison and the reference stimuli differed in loudness or were presented to different electrodes.
Results:
Patients were able to match stimuli on the basis of pulse rate, with varying degrees of accuracy. Deviations from the target and the amount of variability were greater when stimuli were presented to different electrodes. The results also provide evidence regarding level-dependent pitch shifts.
Conclusions:
Because of methodological limitations, conclusions regarding pitch equivalence are limited. However, patients vary significantly in their ability to utilize temporal information.
