NATURE OF AVERAGE EVOKED POTENTIALS TO SOUND AND OTHER STIMULI IN MAN *

Since Geisler, Frishkopf, and Rosenblithl claimed to have recorded cortical responses to auditory stimulation in man by means of a computer averaging technic, there has been considerable interest in the possible application of these methods to problems of central auditory function. In spite of a general acceptance of these findings and their implications for the study of the auditory system,2 a careful assessment of this work and of the more extensive treatment by Geisler3 reveals a number of puzzling features among the variables that seem to affect the response. In an initial attempt to reproduce this response, we also encountered unexpected observations which suggested that the phenomenon should receive some additional study. This was undertaken in experiments now to be described.