Spontaneous Eye Blinks Map the Probability of Perceptual Reinterpretation During Visual and Auditory Ambiguity.

Spontaneous eye blinks are modulated around perceptual events. Our previous study, using a visual ambiguous stimulus, indicated that blink probability decreases before a reported perceptual switch. In the current study, we tested our hypothesis that an absence of blinks marks a time in which perceptual switches are facilitated in- and outside the visual domain. In three experiments, presenting either a visual motion quartet in light or darkness or a bistable auditory streaming stimulus, we found a co-occurrence of blink rate reduction with increased perceptual switch probability. In the visual domain, perceptual switches induced by a short interruption of visual input (blank) allowed an estimate of the timing of the perceptual event with respect to the motor response. This provided the first evidence that the blink reduction was not a consequence of the perceptual switch. Importantly, by showing that the time between switches and the previous blink was significantly longer than the inter-blink interval, our studies allowed to conclude that perceptual switches did not happen at random but followed a prolonged period of nonblinking. Correspondingly, blink rate and switch rate showed an inverse relationship. Our study supports the idea that the absence or presence of blinks maps perceptual processes independent of the sensory modality.