Optimizing exposure: Between-session mental rehearsal as an augmentation strategy.

Exposure therapy is widely empirically supported as a treatment for anxiety disorders, but clinically significant response rates hover around 50%. This study explores strategies for consolidating the exposure memory as a way of improving efficacy. Between-session mental rehearsal of exposure learning was examined as a way of enhancing the effects of exposure therapy. Sixty-two spider-fearful individuals completed baseline questionnaires and a behavioral approach test with a live tarantula, followed by two sessions of in vivo exposures, and a post-assessment one-week later that repeated the baseline questionnaires and behavioral approach test. Skin conductance, subjective distress, and number of steps completed were recorded at each behavioral approach test. Participants were randomized to mental rehearsal or control (non-specific) rehearsal that was prompted on three occasions after each exposure session. Participants in both conditions improved from baseline to post-assessment, but mental rehearsal participants showed significantly greater improvement than control participants across questionnaire measurements of spider fear, subjective distress, and number of steps completed during the behavioral approach test. Findings suggest that between-session mental rehearsal is an effective supplement to exposure therapy. As such, mental rehearsal may be a promising avenue toward increasing treatment response rates across many psychiatric disorders that benefit from exposure therapy.