Face pareidolia in schizophrenia.

Background: Faces convey valuable daily life social signals. As in most psychiatric conditions, non-verbal social cognition or its components including face processing may be aberrant in schizophrenia (SZ). Social participation of individuals with SZ is vital for their quality of life, and remediation of social abilities in this population is of high relevance both for society and clinical care.

Method: Tuning to faces in non-face images such as shadows, grilled toasts, or ink blots is called face pareidolia. Humans possess high sensitivity to facial signals: even fetuses and infants are well tuned to coarse face cues. Here we assessed face tuning in individuals with SZ and person-by-person matched controls by using a new experimental tool, a set of food-plate images bordering on the Giuseppe Arcimboldo style. The key benefit of these images is that single components do not trigger face processing.

Results And Conclusions: The outcome indicates that individuals with SZ exhibit aberrant face tuning in face-like non-face images (χ(1) = 17.44, p = 0.0001) that can hamper adaptive interaction with peers and social participation hindering, in turn, clinical remediation. Face response rate in SZ patients was related to the scores on the event arrangement task tapping social cognition (Pearson product-moment correlation, r = 0.602, p = 0.01) and on picture completion task assessing visual perceptual organization (Spearman's rho = 0.614, p = 0.009). Therefore, poor performance on the face tuning task is unlikely to be accounted for by deviant general cognitive abilities, but rather by impairments in perceptual integration and social cognition. Comparison of these findings with data in autism and other neuropsychiatric conditions provides novel insights on the origins of face tuning in SZ and triggers brain imaging research.