Gradual relation between perceptual awareness, recognition and pupillary responses to social threat

There is substantial evidence supporting the processing of affective stimuli outside of conscious awareness in both healthy individuals and brain-damaged patients. However, the methodologies used to assess awareness are still a matter of debate, with also implications for dichotomous or gradual theories. In two experiments, we investigated how social threat is processed in healthy participants by combining the continuous flash suppression paradigm and the perceptual awareness scale, a fine-grained measure of perceptual awareness. Our findings revealed a gradual relationship between emotional recognition and perceptual awareness, with higher recognition sensitivity for fearful than angry bodies across all visual awareness levels, except during perceptual unawareness where performance was at chance level. Interestingly, angry body expressions were suppressed for a shorter duration than neutral and fearful ones. Furthermore, pupil dilation responses were influenced by affective expression, suppression duration and perceptual awareness level. In conclusion, our results highlight a gradual relationship between behavioral and pupillary responses and perceptual awareness, which is further influenced by the specific stimulus category being processed. In addition, our results illustrate that certain experimental choices, such as stimulus type or the method used to assess awareness, are important factors to be considered in consciousness studies.