Distance- and hierarchy-dependent functional dysconnectivity in schizophrenia and its association with cortical...

Area of Science:

• Neuroscience
• Brain Imaging
• Psychiatry

Background:

• Schizophrenia is linked to widespread brain functional dysconnectivity.
• The spatial scale and structural basis of these alterations are not fully understood.
• Standard methods struggle to capture short-range connectivity relevant to local dysfunction.

Purpose of the Study:

• To investigate the spatial scale and structural correlates of functional dysconnectivity in schizophrenia.
• To apply a distance-dependent analysis of functional connectivity strength (FCS).
• To examine microstructural differences associated with functional alterations.

Main Methods:

• Utilized vertex-wise, distance-dependent analysis of resting-state fMRI data from 86 schizophrenia patients and 99 controls.
• Partitioned FCS by geodesic distance and analyzed by cortical hierarchy.
• Assessed T1/T2 ratio and individualized data-driven functional connectivity density (idFCD) as microstructural proxies.

Main Results:

• Schizophrenia patients showed reduced short-range FCS in the dorsal primary somatosensory cortex, co-localizing with microstructural abnormalities.
• Increased longer-range FCS was observed in transmodal regions (e.g., precuneus) without associated microstructural differences.
• Hierarchical analysis revealed structure-function disruption in primary networks and increased relative FCS in transmodal regions.

Conclusions:

• Schizophrenia exhibits distinct cortical dysconnectivity patterns: short-range reductions in primary sensory areas with microstructural changes, and longer-range increases in transmodal regions.
• These findings highlight the role of short-range connectivity disruptions in primary areas.
• This study offers a complementary framework to conventional analyses by integrating distance-dependent functional measures with microstructural data.