'Social dysmetria' in first-episode psychosis patients

The 'embodied cognition' hypothesis suggests a close relationship between internal self-representations and the outward expression of social behaviours and emotions. Given self-awareness disturbances in patients with first-rank symptoms (FRS), we hypothesized that these patients would show abnormal social behaviours. In this study, we examined the social interactive skills of patients with first-episode psychosis during an interview, together with changes in performance over time.

We analysed previously unreported data from 227 patients with first-episode psychosis (90 with, and 137 without, FRS) who took part in the WHO multicentre study on the Determinants of Outcome of Severe Mental Disorders. They were assessed on the Psychological Impairment Rating Schedule (PIRS) and examined again after 2 years.

A principal component analysis on the Psychosocial Impairment Rating Schedule produced two factors (interactive skills; withdrawal from interactions). Patients with FRS showed greater impairments in the domain linked to 'interactive skills', which remained 2 years after the first experience of a psychotic illness. These findings were not explained by clinical characteristics, or presence of non-FRS delusions.

Self-awareness deficits, as indexed by the FRS symptom cluster, are linked to deficits in social interactive behaviours. These abnormalities are indicative of 'social dysmetria' in this group, which involves difficulties conveying motor aspects of behaviours, volition and affect to facilitate mutual communication. These findings point to the utility of behavioural assessment scales in clinical and research settings.