Abstract
One of the most compelling visual phenomena is motion-induced blindness (MIB; Bonneh et al. 2001), a paradigm in which a distinctly visible stimulus (yellow dot) is made to periodically disappear by its placement within an otherwise coherently moving pattern (rotating blue crosses). MIB has been widely utilized to investigate the neural and cognitive mechanisms responsible for visual awareness. We wondered whether MIB might in fact occur outside of awareness and attention. Following an approach related to that used to study inattention and binocular rivalry (Brascamp & Blake 2012), we probed observers' (n=8) perceptual states after periods during which MIB was presented outside of awareness (suppressed by continuous flash suppression), was unattended (due to a concurrent rapid serial visual presentation task), or both. If the representation of the target fluctuates during this manipulation period (even without awareness and/or attention), it should sometimes be perceptually suppressed after this period due to MIB, resulting in longer reaction times (RT) to report the target item. We found that our manipulations (CFS and/or inattention) had no significant effect on RTs for detecting the target (F3,21=0.08, p=0.97). This suggests that the dynamics of MIB were unaffected by removing awareness, attention, or both. We also devised a baseline condition in which the target dot was physically absent during the manipulation period. In the case of CFS, this condition was perceptually identical to the main condition. Nevertheless, baseline RTs were reliably faster for all of our manipulations, including CFS (F1,7=22.37, p<0.005). Finally, to ensure that target suppression was due to MIB and not CFS, we ran a control in which the normally rotating MIB pattern was stationary and found no effect of CFS (t7=-0.94, p=0.38). Taken together, these results suggest that the phenomenon of motion-induced blindness is unaffected by the removal of awareness, attention, or both.
Meeting abstract presented at VSS 2013