Competing mechanisms in the perception of apparent motion: Effects of zero-hertz and time-varying energy

Anstis, et al. (1985) have reported that under certain conditions the visual system adapts and the perception of apparent motion breaks down. The present research indicates that breakdown is actually a result of same-place mechanisms successfully competing with motion-detecting mechanisms. Thus, the perception of stationarity (with flicker) can occur at the start of a trial and spontaneously switch to the perception of motion, or vice versa. The response of same-place mechanisms depends on the zero-hertz energy at each location of an apparent motion stimulus, whereas the response of motion mechanisms depends on the time-varying energy. Average luminance, luminance contrast, the temporal symmetry of the apparent motion display, and relative phase are manipulated to investigate competition between same-place and motion-detecting mechanisms.