Visual Onset and Offset Latencies

Abstract

An experiment was designed to test the hypothesis that the latency of response to the offset of light can sometimes be shorter than the latency of response to the onset. The subjects’ task involved the temporal order discrimination of the offset of one light and the onset of another. The results indicated that offsets were perceived about 40 ms earlier than onsets. Reasons were suggested for the shorter onset latencies found by other investigators, and a model was proposed to account for changes in the relative latencies of onsets and offsets as a function of stimulus duration and intensity.