Abstract
A digital computer input device has been developed for processing neurophysiological data in real time. It consists of two high speed electronic counters and two A-D converters. They make it possible to deal simultaneously with four different signals. Some examples of the application of this apparatus have been presented: a program for the high speed digitization of interspike intervals, simultaneous analog to digital conversion of EEG and spike frequency, cross-correlation functions between 2 spike trains and between the EEG and a spike train, finally, pre- and post-stimulus time histograms.