Differential Effects of Autistic Traits and Psychotic-Like Experiences on the Interpretation and Inference of Social...

Theory of mind (ToM), the ability of mental state attribution, is an important aspect of social cognition. The autism-psychosis diametrical model suggests that there is an opposite impact of autistic traits and psychotic-like experiences (PLE) upon ToM, with autistic traits associated with under-mentalizing and PLE linked to over-mentalizing. This exploratory study aimed to examine the diametrical model at both subclinical and clinical levels.

We recruited 240 college students (Study 1), 28 patients with chronic schizophrenia and their demographically-matched controls (Study 2). The animated shapes task was used to assess ToM ability. This task was a non-verbal task involving the interpretation of geometric figure interactions in random and ToM conditions. All participants completed the Community Assessment of Psychic Experiences (CAPE) and the Autism-Spectrum Quotient (AQ) to measure PLE and autistic traits. The positive symptom subscale (PANSS-P) and the dimensional autism severity score (PAUSS) of the PANSS were additionally used to assess the severity of positive symptoms and autistic phenotypes in clinical populations.

Patients with chronic schizophrenia demonstrated a mixed pattern of ToM impairment, combining over-mentalizing for random movements and under-mentalizing for movements involving mental state. Correlational analysis preliminarily suggested that regardless of diagnostic status, PLE was associated with over-mentalizing, that is, more intentionality attribution to random movement. Autistic-like symptoms among patients were related to less intentionality with less appropriate answers in ToM condition. However, the interaction of the two symptoms, or the co-occurrence of PLE and autistic traits had no significant beneficial effect on ToM performances.

Autistic traits and positive psychotic symptoms may have differential effects on mentalizing, but there is no support that ToM impairments would be attenuated in individuals with mixed symptom expressions.