Structural connectivity of the salience-executive loop in schizophrenia.

Previously, differences have been shown in effective connectivity of the salience network between healthy controls and patients with schizophrenia. Specifically, the right anterior insula (rAI) fails to modulate the dorsolateral prefrontal cortex (DLPFC). In 35 controls and 31 patients with schizophrenia, we extended these findings by investigating the white matter connectivity of this pathway using tractography, and its relationship with the disrupted effective connectivity. We showed increased fractional anisotropy in the pathway connecting the rAI with the DLPFC, which related to reduced effective connectivity. This may be due to either secondary changes in white matter or a primary defect in structural integrity resulting from deficient axonal pruning. This novel finding warrants further investigation of white matter connectivity in schizophrenia and the mechanisms underlying this pathophysiology.