Figure 1.

Trial schematic of the experiment. A fixation cross was presented center screen for 500 ms after which a visual cue was presented for 2000 ms, indicating the desired motion for that trial (counter-clockwise, clockwise, vertical, horizontal, free-view). This was then replaced by eight iterations of either the V1, V2 (visual only) or V1 + A1, V2 + A2 (visual and auditory) frame cycle (500 ms per frame), yielding 8 s of ambiguous perception. Participants were then instructed to record whether they were able to generate the requested motion for at least some part of the trial, and, to rate the perceptual stability of the trial.