Overly Strong Priors for Socially Meaningful Visual Signals Are Linked to Psychosis Proneness in Healthy Individuals
Heiner Stuke, Elisabeth Kress, Veith Weilnhammer, Philipp Sterzer, Katharina Schmack
Frontiers in Psychology April 8, 2021 Peer reviewed DOI: 10.3389/fpsyg.2021.583637 via OpenAlex 41 citations
Summary
People with stronger tendencies toward hallucinations and delusions are more likely to perceive faces in visual noise and to detect invisible direct gaze, supporting the theory that psychosis involves overweighing high-level prior expectations over sensory evidence. In 39 healthy individuals varying in psychosis proneness, the tendency to see faces in noise correlated with hallucination proneness (r = 0.50) and delusion proneness (r = 0.46). The tendency to detect invisible direct gaze also correlated with hallucination proneness (r = 0.43) but not conclusively with delusion proneness. These findings suggest that overly strong priors for socially meaningful stimuli may represent an early processing alteration in psychosis.
Study at a glance
| Design | cross-sectional study |
|---|---|
| Sample size | 39 |
| Population | healthy individuals with varying degrees of psychosis proneness |
| Key finding | Overly strong priors for detecting faces in noise and invisible direct gaze are associated with hallucination and delusion proneness in healthy individuals. |
Abstract
According to the predictive coding theory of psychosis, hallucinations and delusions are explained by an overweighing of high-level prior expectations relative to sensory information that leads to false perceptions of meaningful signals. However, it is currently unclear whether the hypothesized overweighing of priors (1) represents a pervasive alteration that extends to the visual modality and (2) takes already effect at early automatic processing stages. Here, we addressed these questions by studying visual perception of socially meaningful stimuli in healthy individuals with varying degrees of psychosis proneness ( n = 39). In a first task, we quantified participants’ prior for detecting faces in visual noise using a Bayesian decision model. In a second task, we measured participants’ prior for detecting direct gaze stimuli that were rendered invisible by continuous flash suppression. We found that the prior for detecting faces in noise correlated with hallucination proneness ( r = 0.50, p = 0.001, Bayes factor 1/20.1) as well as delusion proneness ( r = 0.46, p = 0.003, BF 1/9.4). The prior for detecting invisible direct gaze was significantly associated with hallucination proneness ( r = 0.43, p = 0.009, BF 1/3.8) but not conclusively with delusion proneness ( r = 0.30, p = 0.079, BF 1.7). Our results provide evidence for the idea that overly strong high-level priors for automatically detecting socially meaningful stimuli might constitute a processing alteration in psychosis.