IS HUMAN MOTION DETECTION SUBSERVED BY A SINGLE OR MULTIPLE-CHANNEL MECHANISM

Two recent versions of a single channel model of motion perception hav e had impressive success in explaining direction discrimination by hum an observers for spatially filtered noise images in two-flash apparent motion. It has been argued that the dramatic breakdown in motion perc eption which occurs when one image in the two-flash sequence is low-pa ss filtered can be explained only by a single channel model. We show t hat neither version of the single channel model which has been propose d can explain performance for noise images chosen to provide comparabl e stimulation in the spatial channels known to subserve human vision, A multi-channel model of motion perception has little difficulty in ex plaining these results. (C) 1998 Elsevier Science Ltd.