Don't tell anyone: the importance of no-report paradigms in neuroscience of consciousness.

The neural correlates of perceptual awareness are usually investigated by comparing experimental conditions in which subjects are aware or not aware of the delivered stimulus. This, however implies that subjects report their experience, possibly biasing the neural responses with the post-perceptual processes involved. This Neuro Forum article reviews evidence from an electroencephalography (EEG) study by Cohen and colleagues (Cohen M. et al. Journal of Neuroscience 40 (25) 4925-4935) addressing the importance of no-report paradigms in the neuroscience of consciousness. In particular, authors shows of P3b, one of the proposed canonical "signatures" of the conscious processing, is strongly elicited only when subjects have to report their experience, proposing a reconsideration in the approach to the neuroscience of consciousness.