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Data and scripts for "Bifurcation in brain dynamics reveals a signature of conscious processing independent of report" by Claire Sergent1,2,*, Martina Corazzol1,2,¶, Ghislaine Labouret1,2,3,¶, François Stockart1,2, Mark Wexler1,2, Jean Rémi King4, Florent Meyniel5, Daniel Pressnitzer4; Nature Communcations 2020

Does conscious perception occur during initial sensory processing, or does it arise later in a supra modal fashion? If conscious access truly depends on supra modal processes, we may be able to induce “asensory perception”, where only the semantic features of a meaningful stimulus are accessed, untied to its sensory attributes. Here we tested this prediction by degrading the low-level sensory representations of visual words in the brain using pattern masking, and subsequently presenting audio words that were either semantically related to the masked word or not. We hypothesized these retrospective semantic cues would reactivate the remaining traces of the masked word in the brain, and induce awareness of any information that was not disrupted by masking. We have already conducted several experiments to test this hypothesis. Previous experiments on (retro-)perception of masked words included congruent and incongruent (semantically related or unrelated) auditory cues presented before or after the presentation of the visual stimuli. We asked about word identification, visual feature discrimination (position or case) and visibility or confidence depending on the experiment. Results were consistent across experiments regardless of whether the cue appeared before or after the target: in congruent trials participants reported seeing the target more often, performed better at the word identification task, but showed no effect of congruency on visual feature discrimination. We currently feel two additional control experiments in pre- and retro-cueing are necessary to better define the boundaries of the observed effect, and study potential differences in behavior according to time-order of target and cue. The proposed experimental design here uses repetition priming instead of semantic priming, in pre- and retro-cueing. We hypothesize that the effect of repetition priming will be different from that of semantic priming from prior experiments: in repetition priming, participants had increased performance at position discrimination in pre-cueing but not retro-cueing. Pilot studies in repetition priming did not include a measure of visibility, and position discrimination showed smaller effects than case discrimination and was a less reliable protocol for controlling participant’s eye-movements. Here we pre-register a replication of these repetition-priming studies, in which we use case discrimination, include visibility ratings, and use separate groups of participants for pre- and retro- cueing conditions. It is unclear whether the observed difference in detection and performance between congruent and incongruent trials was due to a positive effect of congruency or a negative effect of incongruency. Here, we switched the use of incongruent cues with using the reversed audio from congruent ones to remove any meaning or word-like structure from the incongruent condition.