Attentional influences on the dynamics of motion-induced blindness

Motion-induced blindness (MIB) is a visual phenomenon in which a highly salient, peripheral, visual target spontaneously disappears from visual awareness (and subsequently reappears) when superimposed on a globally moving background of distracters. Here, we investigated the influence of attention on these fluctuations in perception in two experiments. In the first experiment, directing spatial attention to the MIB target (and thus away from the distracters) led to an increased probability of disappearance of the target. This counter-intuitive effect of attention enhancing disappearance is nonetheless consistent with earlier reports that increased target salience enhances disappearance. Conversely, in a second experiment withdrawing attention from the entire MIB display (both target and distracters) led to a decrease in perceptual disappearances and reappearances, as well as prolonged periods of invisibility. Taken together these findings suggest that the global availability of attention facilitates competition between target and moving distracters, while the local direction of attention toward or away from the target can influence the outcome of that competition. Thus, in common with other related perceptual phenomena, attention has complex effects on the dynamics of target-distracter interactions associated with motion-induced blindness.