[Social cognition in schizophrenia and autism spectrum disorder: Points of convergence and functional differences]

Schizophrenia and autistic spectrum disorder (ASD) are two neurodevelopmental disorders that have different symptom presentations, ages of onset and developmental courses. Both schizophrenia and ASD are characterized by marked deficit in communication, social interactions, affects and emotions. Social cognitive impairments in ASD and schizophrenia were demonstrated separately in both disorders. It was reported that these impairments have direct relation with social deficits of both disorders. The apparent similarity between social cognition impairments in ASD and schizophrenia highlights questions about the existence of common or different neurocognitive mechanisms related to social dysfunctions. In order to examine these questions, the present article provides a comprehensive review of all published studies which directly compare individuals with ASD and schizophrenia on the same cognitive tasks of social cognition.

The article search was made on Pubmed, PsycInfo and ScienceDirect, with the items: "autism", "Asperger syndrome", "schizophrenia", "social cognition", "theory of mind", "emotional processing", "social perception", "attributions style". All published studies which compared individuals with ASD and schizophrenia, (diagnosed according to DSM-IV (APA, 1994) criteria and IQ≥70), included control group were considered. The cognitive tasks were categorized according to four domains of social cognition defined by SCOPE (Pinkham et al., 2013): theory of mind (ToM), emotional processing (EP), social perception (SP) and attributional style/bias. The results were analyzed in terms of performances, cognitive profile and patterns of neural activations. Twenty-one published studies and two meta-analytic reviews were analyzed.

Cognitive performance analysis confirms the convergence of abnormalities of people with autism and people with schizophrenia on 1st and 2nd order theory of mind, emotion processing and social perception. Quantitative results show reduced performance in ASD compared to SZ and Ct groups. Differences were observed between ASD and SZ regarding social situation comprehension, visual orientation and visuospatial exploration strategies, and attributional style highlighting different strategies on intentional process. Brain imaging studies show that people with autism present a reduced cerebral activity in several key regions of theory of mind (cingulate regions, superior temporal sulcus, paracentral lobule), and emotional treatment (primary and secondary somatosensory regions), while people with SZ exhibit an inappropriate increased activity in these regions.

The present revue of the studies which directly compare individuals with ASD and schizophrenia on different domains of social cognition indicates that both disorders exhibit differences and similarities with regard to behavioral performances. Results in neuroimaging indicate different neurocognitive mechanisms underlie apparently similar social-cognitive impairments. Further studies are needed to better explore and describe divergent neurocognitive mechanisms in ASD and schizophrenia in order to provide treatment and remediation methods that take into account the specificities of neurocognitive processes in the two disorders.