Neural correlates of visual consciousness in report and no-report paradigms

Sammanfattning

Research on the neural correlates of consciousness (NCC) has increasingly questioned whether late neural activity observed in traditional report-based paradigms reflects conscious perception itself or instead post-perceptual cognitive processes associated with reporting, decision-making, and attention. The present systematic review examined ERP correlates of visual consciousness across report-based, reduced-report, and no-report paradigms, with particular focus on the Visual Awareness Negativity (VAN) and P3/P3b components. Studies were classified according to paradigm type, report requirements, ERP components investigated, and awareness-related findings. The reviewed studies consistently demonstrated that early awareness-related ERP activity generalized more successfully across paradigms minimizing explicit report requirements than late positivity components such as P3/P3b. Across multiple paradigms, including visual masking, attentional blink, and inattentional blindness paradigms, late positivity effects were substantially reduced, absent, or dissociated from awareness when reporting requirements or task relevance were minimized. By contrast, awareness-related negativities within the VAN/N2 time range persisted across several methodological conditions. Comparisons between report paradigms and paradigms progressively minimizing post-perceptual processing further suggested a methodological continuum rather than a strict report versus no-report dichotomy. Overall, the findings support interpretations proposing that late ERP components primarily reflect post-perceptual cognitive operations, whereas earlier ERP activity constitutes a more plausible candidate correlate of conscious visual perception. The review additionally highlights the importance of paradigm design in interpreting candidate NCCs and contributes to ongoing theoretical debates concerning the relationship between conscious perception, cognitive access, and report-related processing.