Altered coordination between the default mode, central executive, and salience networks is linked to schizophrenia, but its role in earlier at-risk stages is unclear. Using dynamic functional connectivity and co-activation pattern analysis of resting-state fMRI, this study examined right anterior insula interactions in 19 individuals with subthreshold delusions and hallucinations (UHR), 28 with basic symptoms of self-experienced subclinical disturbances (BS), and 29 healthy controls. The right anterior insula governs transitions from the central executive to default mode network, which become dysfunctional before psychosis onset, especially when attenuated psychotic symptoms emerge.
Dopamine reduces functional connectivity between the right anterior insula, a central hub of the salience network, and the left auditory cortex planum polare. In healthy men given a placebo, higher psychotic-like experiences correlated with weaker connectivity between these regions; in those given L-DOPA, higher psychotic-like experiences correlated with stronger connectivity. The score on a measure of psychotic-like experiences explained about 30% of the variation in connectivity between the two groups. These results suggest that psychotic-like experiences are linked to dopamine-induced disruption of auditory input to the salience network, potentially leading to aberrant attribution of salience.