Background:
Patients with schizophrenia are observed to have marked deficits across several social cognition domains including theory of mind (TOM), social perception and emotion processing. These deficits are observed at illness onset (TOM, Polowsky et al. 2002) and across illness phase (TOM, Janssen et al. 2003), and differ in presentation from those observed in other diagnostic groups (eg depression, Garety & Freeman 1999; affective disorder, Loughland et al. 2002), suggesting they may represent a trait marker for the disorder. The aim of this paper was to review current findings with regard to social cognition deficits in schizophrenia and to examine the evidence that these deficits may represent a vulnerability marker.
Method:
A narrative review of the research literature was undertaken and supplemented with the current research findings of the author that investigate emotion-processing deficits in people with schizophrenia, first-degree relatives, affective disorder and healthy non-psychiatric controls.
Results:
Findings from TOM, social context and emotion processing provide evidence that healthy first-degree relatives and other at-risk groups show similar, but less severe, social cognition deficits to those observed in schizophrenia (Cornblatt & Keilp 1994; Frenkel et al. 1995; Toomey et al. 1999; Loughland et al. 2004).
Conclusions:
The results support the notion of a social cognition vulnerability marker for schizophrenia disorder. Differential patterns of performance on social cognition tasks may help detect those potentially at risk of developing schizophrenia and provide a potential method for developing endophenotypes for examining diagnostic, genetic and therapeutic issues in schizophrenia.
