Consciousness remains a formidable challenge. Different theories of consciousness have proposed different mechanisms to account for phenomenal experience. Here, appealing to Global Workspace Theory, Higher-Order Theories, Social Theories, and Predictive Processing, we introduce a novel framework -the Self-Organizing Metarerpresentational Account (SOMA), in which consciousness is viewed as something that the brain learns to do. The brain continuously and unconsciously learns to redescribe its own activity to itself, so developing systems of metarepresentations that qualify target first-order representations. Experiences only occur in experiencers that have learned to know they possess certain first-order states and that have learned to care more about certain states than about others. Thus, consciousness is the brain's (unconscious, embodied, enactive, non-conceptual) theory about itself.

Can people categorize complex visual scenes unconsciously? The possibility of unconscious perception remains controversial. Here, we addressed this question using psychophysical methods applied to unmasked visual stimuli presented for extremely short durations (in the μsec range) by means of a custom-built modern tachistoscope. Our experiment was composed of two phases. In the first phase, natural or urban scenes were either absent or present (for varying durations) on the tachistoscope screen, and participants were simply asked to evaluate their subjective perception using a 3-points scale (absence of stimulus, stimulus detection or stimulus identification). Participants' responses were tracked by means of two staircases. The first psychometric function aimed at defining participants' proportion of subjective detection responses (i.e., not having seen anything vs. having seen something without being able to identify it), while the second staircase tracked the proportion of subjective identification rates (i.e., being unaware of the stimulus' category vs. being aware of it). In the second phase, the same participants performed an objective categorization task in which they had to decide, on each trial, whether the image was a natural vs. an urban scene. A third staircase was used in this phase so as to build a psychometric curve reflecting the objective categorization performance of each participant. In this second phase, participants also rated their subjective perception of each stimulus on every trial, exactly as in the first phase of the experiment. Our main result is that objective categorization performance, here assumed to reflect the contribution of both conscious and unconscious trials, cannot be explained based exclusively on conscious trials. This clearly suggests that the categorization of complex visual scenes is possible even when participants report being unable to consciously perceive the contents of the stimulus.

The goals of this study were (1) to develop a novel type of no-report paradigm capable of capturing people's phenomenal experience when they see complex images, and (2) to explore the extent to which such images can be processed in the absence of consciousness. To this end, we took advantage of a powerful technique derived from electroencephalography: the steady state visual evoked potentials (SSVEP) technique. We used faces embedded in sequences of non-face stimuli, which we manipulated the contrast of so as to create subliminal and supraliminal conditions. Our results are twofold. On the one hand, they indicate that the SSVEP response, which signalled the ability of the brain to categorize faces, was strongly reduced, but nevertheless maintained, when participants reported being unable to see the stimuli. In this condition, the response was confined to early visual stages, whereas it propagated through the ventral stream in conditions in which image contrast increased. On the other hand, the method appears as useful to consider as a novel instance of a no-report paradigm because it requires no overt behavioural response and because its outputs (signal magnitude and scalp topography) predict people's self-reported phenomenal experience.

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