Unconscious perception of race shapes conscious race categorization in the brain

The visual perception of race is a process that occurs within the first 200 ms of face presentation (de lissa et al., 2021). Such a fast decisional process implies very early activation of neural pathways sensitive to what must be relatively low-level visual aspects of faces. Of particular relevance to the fields of social and visual neuroscience is the finding that a reliable reaction time advantage is typically observed for the categorization of ‘other’ race faces compared to ‘same’ race faces (relative to the observer). To further clarify the timeline of activation and interplay between neural and behavioural indices of the Other-Race Categorization Advantage (ORCA), we employed a masked priming paradigm in combination with electroencephalography (EEG) to explore the relationship between the two. West Caucasian (WC) and East Asian (EA) faces were presented as masked primes and visible targets while participants performed a race categorization task. Significant facilitation and interference effects were observed for both congruent and incongruent race-primes, respectively, whereas the ORCA was enhanced in both congruent and incongruent conditions. While clear priming effects were observed in the N170 and N250 brain potentials, the N250 exhibited the clearest index of prime congruity. Correlational analyses between reaction times and EEG suggest an early integration of prime and target which has differential effects related to the speed at which same and other race faces are processed. Such effects have implications for a possible separation or divergence of neural pathways activated during explicit race categorization. Additionally, a heightened unconscious perception of other race faces has the potential for profound behavioural effects unrelated to race categorization.