PRESENT STATUS AND FUTURE DEVELOPMENT OF THE COCHLEAR PROSTHESIS

SUMMARY- Presently devised single channel devices generate relatively primitive sensa-tion of hearing. They provide some enhancement of communication skills for the totally deaf. Definite psychological advantages for the totally deaf have been observed. Pitch discrimination is by the mechanism of "periodicity pitch. " No "place " pitch encoding is possible. The recog-nition of complex sounds is not possible. Multiple segments of auditory nerve must be stimulated in a manner which will simulate the complex patterns of neural activity necessary for speech discrimination. Electrodes can be optimized and the pathophysiological consequences of elec-trical stimulation can be determined in experimental animals. The perceptual consequences of electrical stimulation, however, can best be determined in man himself. How much we will have to rely on known and future methods of aural rehabilitation will depend upon how well perceptual speech patterns can be generated by electrical stimulation of the auditory nerve. Speech discrimination by ear alone has not been possible with the aid of any cochlear prosthetic device so far devised. The limited sensation of hear