Victor Pokorny¹ (), Lauren Ellman², Gregory Strauss³, Elaine Walker⁴, Scott Woods⁵, Albert Powers⁵, Philip Corlett⁵, Steven Silverstein⁶, James Waltz⁷, James Gold⁷, Jason Schiffman⁸, Vijay Mittal¹; ¹Northwestern University, ²Temple University, ³University of Georgia, ⁴Emory University, ⁵Yale University, ⁶University of Rochester, ⁷University of Maryland, ⁸University of California, Irvine

Positive symptoms, such as hallucinations and delusions, are core features of psychotic disorders and are elevated in individuals at risk for developing psychotic disorders. We, and others, have hypothesized that positive symptoms, especially hallucinations and perceptual distortions, are caused by overweighting of perceptual priors. We administered two tasks that are hypothesized to reflect overweighting of perceptual priors, a visual Mooney Faces task and an auditory Sine Wave Speech task, to over 800 adolescents and young adults oversampled for psychosis risk. Both tasks required participants to indicate whether they recognized naturalistic stimuli (faces or speech) that were heavily filtered to create ambiguous perceptual experiences. We observed a significant correlation between recognition rates produced by the Mooney Faces task and the Sine Wave Speech task (r(765)=0.32, p<.001, 95% CI [0.26,0.38]). Thus, these tasks appear to jointly reflect overweighting of perceptual priors, despite differing with respect to perceptual modality. Recognition rates from both tasks independently predicted positive symptom severity (Mooney faces: r(784)=0.19, p<.001, 95% CI [0.12,0.26]; Sine Wave Speech: r(818)=0.16, p<.001, 95% CI [0.1, 0.23]). However, a composite score (combining indices from both tasks) exhibited a stronger association than either task individually (r(760)=0.23, p<.001, 95% CI [0.16,0.29]). Our results suggest that multisensory overweighting of perceptual priors may, in part, explain the provenance of positive symptoms in those at risk for developing psychosis. Furthermore, we argue that tasks that measure such overweighting may be useful for better identifying individuals at risk for developing such disorders.

Acknowledgements: This research was funded by National Institutes of Health (R01MH120090, R01MH112613, R01MH120091, R01MH120092, R01MH116039, R21MH119438, R01MH112545, R01MH1120088, U01MH081988, R01MH112612, R01MH120089).