Augmenting Extinction with Counterconditioning Strengthens and Sustains Neural Safety Representations in PTSD

Because extinction forms the empirical foundation of exposure therapy, strategies to enhance extinction could lead to more effective interventions for post-traumatic stress disorder (PTSD). Here, we used functional MRI to compare immediate and long-term efficacy of enhanced versus standard extinction in 54 adults with (n=32) and without (n=22) PTSD. In both control and PTSD groups, counterconditioning—an enhanced form of extinction that replaces threat with positive outcomes—was more effective than standard extinction. It reduced threat-related neural activity and promoted reinstatement of safety (extinction) patterns in the ventromedial prefrontal cortex (a region involved in learning and retrieving safety associations). However, the PTSD group continued to reinstate both threat- and safety-related neural patterns in the dorsal anterior cingulate cortex (a region involved in learning and retrieving threat associations). These findings represent novel evidence that enhanced extinction outperforms standard extinction in promoting more rapid and persistent neural representations of safety in PTSD.