Abnormal Functional Connectivity Pattern of the Reward Circuitry Is Associated with Negative Symptoms and Cognitive Functions in First-Episode Schizophrenia.

Background

This study aimed to investigate the relationship between abnormal functional connectivity (FC) patterns in the reward circuitry of the brain and negative symptoms and cognitive impairment in individuals with first-episode schizophrenia (FES).

Methods

Fifty-two FES patients and 59 healthy controls (HCs) were recruited for this cross-sectional study. Thirteen brain regions associated with the reward circuitry were defined as regions of interest (ROIs), and FCs between each ROI and the whole brain were analyzed. Cognitive function was assessed by the MATRICS Consensus Cognitive Battery.

Results

Within-network analyses indicated that, compared to HCs, FES patients exhibited increased FCs between the left ventrolateral prefrontal cortex and left thalamus, which negatively correlated with negative symptoms. Whole-brain analyses revealed some weakened FCs in FES patients compared to those in HCs. The FCs between the right nucleus accumbens and right insular lobe and between the right putamen and both the left anterior cingulate cortex and left precentral gyrus positively correlated with attention/vigilance only in HCs. Additionally, the FC between the left putamen nucleus and left inferior frontal gyrus positively correlated with verbal and visual learning only in HCs.

Conclusion

These findings highlight the differential FC patterns in the reward circuitry in FES patients and indicate that the enhanced within-network FC observed in these patients may contribute to their negative symptoms. The absence of correlations between certain FCs and attention, verbal learning, and visual learning can be explained by decoupling of the reward circuitry from the cognitive control brain regions.