The relationship between cognitive insight and cognitive performance among individuals with at-risk mental state for developing psychosis.

Impairments in cognitive insight-the capacity to appraise and modify one's own distorted beliefs-are believed to be associated with the formation of psychosis. Nevertheless, the association between cognitive insight and cognitive function among people with at-risk mental state (ARMS) for developing psychotic illness has not been made clear. In this study, we used the Beck Cognitive Insight Scale (BCIS) to assess cognitive insight and the Brief Assessment of Cognition in Schizophrenia (BACS) and the Wisconsin Card Sorting Test (WCST) to assess cognitive functions. Fifty subjects with ARMS and 29 healthy volunteers were recruited as participants. The scores for the two groups on the BCIS, BACS, and WCST were compared and Spearman's rank correlations between the domains of the BCIS and cognitive performance were examined in each group. No significant differences were found in BCIS scores between these groups, whereas all of the cognitive function scores were poorer in the participants with ARMS. In the ARMS group, higher self-certainty on the BCIS was significantly correlated with lower performance in the mean number of categories achieved (ρ=-0.31, P=0.03) and perseverative errors of the Nelson type (ρ=0.29, P=0.04) on the WCST. This indicates that excessively high self-certainty might be linked with weaknesses in cognitive flexibility or set-shifting ability in people with ARMS.