Altered Functional Brain Network Structure between Patients with High and Low Generalized Anxiety Disorder

Area of Science:

• Neuroscience
• Psychiatry
• Computational Neuroscience

Background:

• Generalized anxiety disorder (GAD) affects millions globally, yet its underlying neural mechanisms remain incompletely understood.
• Previous research suggests alterations in brain connectivity may be associated with GAD severity.

Purpose of the Study:

• To investigate differences in functional brain network structures between individuals with high (HGAD) and low (LGAD) levels of generalized anxiety disorder.
• To explore the relationship between GAD severity and specific brain network metrics.

Main Methods:

• Resting-state electroencephalogram (EEG) was recorded from 30 LGAD and 21 HGAD patients.
• Functional connectivity was assessed using the Phase Lag Index (PLI) to construct brain networks.
• Network properties, including characteristic path length, clustering coefficient, and small-world attributes, were calculated.

Main Results:

• HGAD patients showed significantly increased PLI in alpha2 rhythms and decreased PLI in theta and alpha1 rhythms compared to LGAD patients.
• Small-world attributes were below one for all rhythms in both groups, indicating a deviation from optimal network organization.
• HGAD patients exhibited significantly lower small-world values in theta and alpha2 rhythms than LGAD patients.

Conclusions:

• Brain functional network structure deteriorates with increasing generalized anxiety disorder severity.
• The findings highlight specific alterations in brain network dynamics associated with GAD, particularly in theta and alpha rhythms.
• These insights may inform the development of targeted interventions for GAD by addressing underlying neural network changes.