Abstract
Transcranial magnetic stimulation (TMS) of the occipital pole is known to suppress perception of visual targets, when applied 100 ms after the target. TMS can also induce a brief phosphene. Here we report a novel TMS induced phenomenon: an illusory repetition of visual events happening either shortly before or shortly after magnetic stimulation. These illusory percepts are not phosphenes: they have the same features as the original stimulus, effectively function as primes, and their perceived features are modulated by visual context. The timing of the phenomenon strongly suggests that the brain tries to interpret the neural activity induced by magnetic stimulation, and uses visual information presented shortly before or after TMS to construct a visual percept. This active construction of conscious perception is affected by events happening up to 450 ms afterwards, strongly suggesting that visual awareness is an extremely sluggish process. We believe the phenomenon we present here offers new possibilities to study the neural mechanisms of conscious visual perception and its timecourse.