Altered Dynamic Functional Connectivity in Early Psychosis Between the Salience Network and Visual Network

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Early psychosis is characterized by altered static functional connectivity between the salience network (SN) and cognitive networks.
• It remains unclear if these alterations extend to dynamic functional connectivity (dFC) or involve lower-order sensory networks.

Purpose of the Study:

• To investigate the temporal dynamics of SN functional connectivity in early psychosis.
• To examine dFC alterations between the SN and both higher-order (default mode network) and lower-order (visual) networks.

Main Methods:

• Utilized sliding window analysis on fMRI data from 26 individuals with first-episode schizophrenia (FES), 20 at clinical high risk for psychosis (CHR), and 37 healthy controls (HC).
• Focused on core SN regions: bilateral anterior insula (AI) and anterior cingulate cortex (ACC).
• Assessed dFC with whole-brain voxels, including visual and default mode network regions.

Main Results:

• FES and CHR groups exhibited reduced dFC variability between bilateral AI/ACC and visual network regions compared to HC.
• The FES group showed less ACC-visual network dFC variability than the CHR group.
• Increased dFC variability was observed between the right AI and the left precuneus (DMN) in both FES and CHR groups.

Conclusions:

• Confirms abnormal dynamic functional interactions between the SN and the default mode network in psychosis.
• Highlights disrupted communication between the SN and lower-order sensory networks as a significant aspect of psychosis' neural underpinnings.