Signal preprocessing system for the small intestinal electromyogram.

The intestinal EMG obtained from chronically implanted electrodes in canine preparations provides for the evaluation of intestinal motor activity and its control. The basic electrical rhythm (BER) and spike components on the EMG signal provide evidence of control activity and a measure of contraction intensity, respectively. A hardware system is presented in which these two components are separated by filters and the contraction spikes counted in fixed epochs to yield a contraction spike per unit time record against time. The signal is also available in parallel binary form at the end of each epoch, together with a data-ready signal for direct acquisition by computer. Tests of system performance and operating protocols are given. The preprocessor is used as a fast front end to a digital signal processing system specifically built for intestinal EMG analyses.