Digital memory recorder in electromyography and nerve conduction studies.

Specifications are given: (i) for a 3-channel digital memory that, when connected to an inkjet writer, allows action potentials from muscle and nerve to be recorded without distortion (upper limiting frequency 10,000 Hz); (ii) for a 14-channel digital memory connected to a 14-channel inkjet writer for the measurement of the territory of the motor units by recording simultaneously from 14 leads of a multi-electrode spaced over the cross-section of the muscle; (iii) for a digital circuit that rejects signals that exceed a given amplitude and duration and interfere with electronic averaging of potentials from sensory nerve less than 1 muV in amplitude.