Abnormal dynamic functional connectivity density in patients with generalized anxiety disorder

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Generalized anxiety disorder (GAD) is characterized by abnormal static functional connectivity (FC) between brain regions.
• Dynamic changes in FC in GAD patients remain largely unexplored.

Purpose of the Study:

• To investigate whole-brain dynamic FC changes in GAD patients.
• To assess the temporal variability of FC using dynamic FC density (dFCD).
• To correlate dynamic connectivity patterns with GAD symptom severity.

Main Methods:

• Combined global FC density (FCD) and sliding window correlation analyses.
• Calculated the standard deviation of dynamic FCD (dFCD) to measure temporal variability.
• Utilized support vector regression to predict symptom severity based on dynamic connectivity.

Main Results:

• GAD patients exhibited higher dFCD variability in the bilateral dorsomedial prefrontal cortex (dmPFC) and left hippocampus.
• Lower dFCD variability was observed in the right postcentral gyrus of GAD patients.
• Abnormal dFCD variability in the left dmPFC significantly predicted anxiety.

Conclusions:

• Altered time-varying connectivity in frontolimbic and sensorimotor areas suggests disrupted neural communication in GAD.
• Findings deepen the understanding of the neural underpinnings of GAD.
• Future research should address sliding window parameters and medication effects in larger, medication-free samples.