A Psychophysiological Study of Compensatory Tracking on a Digital Display

Comparable performance on a compensatory tracking task was achieved with a purely digital altimeter display and with a combined digital and scale-and-pointer display. Performance of a subsidiary, light responding, task was degraded significantly when the digital task was employed. In the presence of the subsidiary task a larger change was recorded in a number of physiological variables (heart rate, muscle activity, skin resistance and respiration) with the digital than with the counter-pointer display. Thus, both performance and physiological measures indicated that parity of performance on the primary task was achieved by increased 'effort' when using the digital display.