How does a figure appear and disappear in visual perception?
9 simple outline figures served as stimuli. Each figure was for 60 msec. projected onto a screen 2 m. from the subject. 1 to 5 fixation areas were chosen for the figures; they were unmarked. After training all subjects reported experience of movement, i.e., fixating a given figure at a given fixation area, subjects reported experiencing the figure as lengthening/expanding from the fixation area to full size and immediately thereafter shortening/contracting to the fixation area. Subjects only saw the figure at its full size for a very short movement. When the fixation area was changed for a figure, the experienced movement also changed, but the fully developed figure remained the same. The durations of subjects' experiened movements of the figures, and thereby the durations of subjects' perception of the figures, were measured in milliseconds. For a given subject the durations of perception of all 9 figures were the same. The durations are characteristic of each subject and have proved to remain constant after a period of 1 yr.
D000328:Adult; D005403:Fixation, Ocular; D005556:Form Perception; D006801:Humans; D007088:Illusions; D009039:Motion Perception; D009903:Optical Illusions; D012858:Size Perception