Changes in Brain Network Connections after Exposure and Response Prevention Therapy for OCD in Adolescents and Adults

Functional alterations of tripartite neural networks during cognitive control (i.e., frontoparietal network [FPN], cingulo-opercular network [CON], and default mode network [DMN]) occur in patients with obsessive-compulsive disorder (OCD), and may contribute to illness expression. However, the degree to which changes in these networks are elicited by gold standard treatment (e.g., exposure and response prevention; EX/RP) remains unknown. Understanding how EX/RP modulates network connectivity in adolescent versus adult patients with OCD may aid the identification of developmentally-sensitive treatment targets that enhance cognitive control. A total of 169 adolescent (13-17 years) and adult (25-40 years; 57% female) patients with OCD (n=111) and healthy controls (HC; n=58) were randomized to either EX/RP or an active control therapy (stress management training; SMT). Participants performed a flanker task during functional magnetic resonance imaging (fMRI) pre- and post-treatment. To retain sensitivity to individual differences in connectivity, Group Iterative Multiple Model Estimation (GIMME) was used to assess functional connectivity (i.e. density) within and between brain networks. Significant increases in FPN density and decreases in FPN-DMN density were observed from pre- to post-treatment in patients who received EX/RP. The opposite patterns of change occurred in those who received SMT. These treatment-related changes in network density did not differ across age group. Results suggest EX/RP-specific changes in task-based connectivity in patients with OCD. Given baseline differences between HC and patients by age group, these treatment-related changes may indicate restoration of healthy FPN and DMN development across patients, providing targets for improving response to EX/RP.