1. A method to assess vision function, comprising: providing a sequence of test images on a display to a test subject, said display coupled to a computer, during a stimulus interval; and providing a response pattern image on said display to said test subject for each of said sequence of test images during a response interval after said stimulus interval; wherein: each of said sequence of test images includes multiple stimulus patterns arranged around a fixation target; said response pattern image includes multiple response targets, each of which corresponds to a location of each of said multiple stimulus patterns; at least one of said multiple stimulus patterns differs from others of said multiple stimulus patterns; and an assessment of a vision function of said test subject is based at least partially on a selection by said test subject during said response interval, for each of said sequence of test images, of at least one of said multiple response targets of said response pattern image that said test subject indicates corresponds to a location of said at least one of said multiple stimulus patterns that differs from others of said multiple stimulus patterns.