Auditory Responses in Tay-Sachs Disease

It is demonstrated that local diagnosis of the hearing impairment and evaluating of the degenerating process in the central nervous system in Tay-Sachs disease may be possible by means of various kinds of audiometric methods applicable to young children, such as cerebral evoked response audiometry using a computer as well as startle response, auropalpebral reflex (APR) and cochleopupillary reflex (CPR) audiometries. Thresholds of startle response, APR, CPR during sleep and cerebral evoked potentials in response to sound stimuli were measured in three patients with Tay-Sachs disease. The thresholds of the startle response, APR and CPR were found to be comparable to those in normal newborn infants and normal young children, whereas no auditory cerebral evoked responses were detected by an average response computer even at the maximum intensity except for a case with the threshold of 80 dB. Since the startle response as well as APR and CPR may be integrated at the level of the brain stem and the cerebral evoked response may arise from the cerebral cortex over a wide area, it is suggested that the lack of the auditory cerebral evoked response probably reflects a predominant degeneration of the higher supranuclear auditory pathways.