Project V is concerned with the behavioral analysis of the biophysical mechanisms underlying cochlear implant function. Behaviorally trained cats will be deafened unilaterally and implanted with an experimental 11- electrode point-source array. Auditory function under conditions of intracochlear electrical stimulation will be assessed using standard psychophysical paradigms to ascertain absolute threshold, loudness growth, dynamic range, and difference limens for frequency and intensity. Once trained, behavioral performance of a given animal on a given task will be determined for multiple electrical field coupling configurations. Following stabilization of an animal's behavioral performance, electrophysiological recordings of single-cell activity will be obtained in acute experiments, using the same stimuli and testing paradigms that had been employed behaviorally. Animals will then be sacrificed, and their cochleas will be processed histologically to determine the number and spatial positions of surviving spiral ganglion cells. The behavioral, physiological and anatomic data will then be merged and analyzed in the context of neural-behavioral models designed to account for perceptual performance on the basis of patterns of neural activity and tailored to reflect the anatomic condition of the spiral ganglion in the tested animal.

Project Start
Project End
Budget Start
Budget End
Support Year
2
Fiscal Year
1991
Total Cost
Indirect Cost
Name
University of Texas Medical Br Galveston
Department
Type
DUNS #
041367053
City
Galveston
State
TX
Country
United States
Zip Code
77555