Detection of motion discontinuities between complex motions

Three main experiments were performed to evaluate the ability of human observers to detect non-homogeneity in a motion field caused by the presence of two adjacent complex motions, having a common motion component. The detection performance varied significantly depending on the common motion component in the motion field. The highest detection rate was observed when the common motion component was radial or rotational flow. The results imply that the selectivity to the presence of a complex motion in the optic flow depends both on the sensitivity of specialized mechanisms tuned to different complex motions and on inhibition of the units tuned to similar motions.