Social cognition link to positive psychotic symptoms
medwireNews: Impaired social cognition in young people is a marker of psychotic, rather than affective, conditions and is specific to positive symptoms, research suggests.
All 115 patients in the study, who were an average age of 21 years, completed the Reading the Mind in the Eyes Test (RMET). The 23 patients with psychosis got significantly fewer correct answers relative to the 52 patients with depression and the 40 with bipolar disorder, who did not differ from each other.
The difference between patients with psychotic and affective disorders was evident for RMET questions previously rated as easy, as well as for difficult ones, report Adam Guastella (University of Sydney, Australia) and colleagues.
The team notes that the findings cannot establish the existence and direction of causality, but says: “One possibility is that social cognitive deficits, such as impaired Theory of Mind, may interrupt one's ability to quickly process and accurately assess social information, which, in turn, could contribute to the development and exacerbation of delusional and paranoid thinking.”
Both positive and negative symptoms on the Brief Psychiatric Rating Scale correlated with RMET performance. However, in a predictive model that included patients’ results on a battery of neurocognitive tests, only positive symptoms were significantly associated with RMET performance; this explained 5.9% of the variance in positive symptoms over and above the 9.7% accounted for by demographics and neurocognitive test results.
By contrast, demographics and neurocognitive findings explained 23.9% of the variance in negative symptoms, and RMET performance did not improve on this.
“This suggests that the unique contribution that the RMET performance provides to symptom presentation seems specific to the positive symptoms of psychosis,” Guastella et al write in Schizophrenia Research.
They note that results on almost all of the neurocognitive tests correlated with RMET performance, and suggest that the “more traditional” tests of neurocognition account for the link between social cognition and negative symptoms.
The researchers suggest that future studies should examine the link between social cognition and symptoms in relation to social functioning. “This is of particular interest,” they say, “as social functioning is a key goal of targeted social cognition treatment efforts.”
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By Eleanor McDermid, Senior medwireNews Reporter