Tracking performance with advanced and delayed visual displays.

Abstract

Human operator performance in continuous pursuit tracking when the stimulus either disappeared prior to the appropriate response time or appeared subsequently to that time was investigated. Tracking was one-dimensional, the stimulus appeared to vary randomly, and feedback of results wasn't provided. The stimulus, consisting of the sum of three low-frequency sine waves, appeared on recording paper tape, moving at 1.0 cm/sec. Masks hid the display in steps up to 1.0 secs, before or 0.5 secs. after the position of a manually-controlled pointer. Timing performance was measured by the peaks of cross-correlations of stimulus/response data pairs which had been successively shifted in time. Tracking performance was measured by RMS error. Timing was increasingly too early for advanced displays but followed closely the actual appearance time of delayed displays. RMS tracking error increased with increasingly advanced and delayed displays. Practice effects were negligible.