Functional connectivity changes in obsessive-compulsive disorder following exposure and response prevention.

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Obsessive-compulsive disorder (OCD) is associated with altered functional connectivity (FC) in brain networks, including the default mode (DMN), salience (SN), and central executive network (CEN).
• The evolution of these brain connectivity patterns following treatment for OCD remains poorly understood.

Purpose of the Study:

• To investigate changes in static and dynamic resting-state functional connectivity (FC) within and between the DMN, SN, and CEN in adults with OCD before and after intensive exposure and response prevention (ERP) therapy.
• To explore the relationship between connectivity patterns and symptom severity, as well as treatment outcomes.

Main Methods:

• Utilized independent component analysis (ICA) and sliding-window approaches to assess static and dynamic FC in 25 adults with OCD and 21 healthy controls (HCs).
• Data were collected at baseline, one week, and three months following the Bergen 4-Day Treatment (B4DT) ERP program.

Main Results:

• At baseline, adults with OCD exhibited altered static FC within the DMN and SN and distinct dynamic connectivity states compared to HCs.
• Following the 4-day ERP treatment, abnormal static and dynamic connectivity patterns in OCD patients normalized and were sustained at three months.
• Increased state transitions correlated with reduced OCD, anxiety, and depressive symptoms. Higher baseline SN-CEN connectivity was linked to greater symptom severity, while post-treatment reductions in CEN and CEN-SN connectivity correlated with improved depressive symptoms.

Conclusions:

• Intensive ERP treatment effectively normalizes both static and dynamic functional connectivity within and between the triple networks in adults with OCD.
• Dynamic FC metrics, in addition to static measures, show promise as clinically relevant biomarkers for assessing therapeutic response in OCD.