PULSE-RATE MATCHING BY COCHLEAR IMPLANT PATIENTS - EFFECTS OF LOUDNESS RANDOMIZATION AND ELECTRODE POSITION

Objective: To assess the accuracy with which cochlear implant patients are able to match two stimuli on the basis of pulse rate pitch. Desig n: Patients were required to adjust the pulse rate of a comparison sti mulus to match that of a fixed reference stimulus. The comparison and the reference stimuli differed in loudness or were presented to differ ent electrodes. Results: Patients were able to match stimuli on the ba sis of pulse rate, with varying degrees of accuracy. Deviations from t he 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 method ological limitations, conclusions regarding pitch equivalence are limi ted. However, patients vary significantly in their ability to utilize temporal information.