No Stopping and No Slowing: Removing Visual Attention with No Effect on Reversals of Phenomenal Appearance

We investigated whether visual selective attention contributes to the reversals of phenomenal appearance that characterize multi-stable displays. We employed a rotating-ring display that reverses appearance only at certain phases of its rotation (i.e., when in full-frontal view). During this critical window of time, observers were required to perform a shape discrimination task, thus diverting attention from the rotating ring. Our results showed that perceptual reversals were neither stopped nor slowed by this manipulation. In contrast, interrupting the display during the critical times increased the frequency of perceptual alternations significantly. Our results go beyond earlier findings that sustained withdrawal of attention slows, but does not stop, perceptual reversals. Accordingly, the available evidence strongly suggests that visual selective attention plays no causal role in multi-stable perception.