Perceiving the shape of the world : the usefulness of motion perspective information under brief exposure durations
The aim of the experiments reported here was to examine the effectiveness of motion perspective to provide sufficient proximal information for subjects to discriminate between various types of stimulus presentations presented at brief exposure durations. Throughout, the duration of presentation was limited to under one second - the duration of simulated movement ranging from one space-time transformation to fifteen space-time transformations. With the exception of Experiment 1, the technique of stimulus generation made use of random-dot patterns. The stimulus patterns were complex, in general consisting of 11,112 spots randomly distributed in an array of 796 (horizontal) by 770 (vertical) possible spot locations. In addition to 'signal' dots which were transformed to new positions according to the rules of perspective, individual frames in the film displays also contained a large amount of visual 'noise' in the form of dots which appeared randomly in the array.