Paranoid beliefs are associated with sensory imprecision in gaze processing

Background. The ability to detect gaze direction is fundamental to social interaction, providing cues about others’ goals, intentions, and attentional focus. Disruptions to this process are observed in psychiatric conditions such as schizophrenia, where persecutory delusions or paranoid thinking are common. A recent study using a paradigm known as breaking continuous flash suppression (b-CFS) has shown that healthy individuals who believe they are being watched on CCTV show alterations in the automatic processing of gaze; their visual system discriminates direct from averted gaze almost a second faster than controls. Importantly, this hypersensitivity does not extend to other stimuli, suggesting a belief about being watched may directly facilitate gaze processing. Methods. In the present study, we examined whether trait paranoia, involving persistent beliefs about persecution and being watched, has a similar influence on gaze processing. A neurotypical participant sample was divided into two groups: low paranoia (N=26) and high paranoia (N=24), and were tested on the b-CFS face detection paradigm. Results. Low-paranoia participants showed normal automatic gaze processing, specifically, they showed the direct gaze advantage. The high-paranoia group did not show a direct gaze advantage or any hypersensitivity to gaze. Moreover, the severity of paranoia and particularly self-reference ideation predicted the effects. Conclusions. These results are in line with hierarchical Bayesian inference accounts of perception and belief formation; individuals who have a stronger tendency to believe they are being watched experience gaze differently, with greater ambiguity in determining where the other person is looking.