A mechanism for persistence and resolution of anxiety after exposure therapy

Exposure therapy is the most effective treatment for anxiety disorders. However, even after successful treatment, with time many experience spontaneous recovery of fear and even full relapse. Two modifications of exposure therapy, spacing sessions and using memory retrieval cues, have been shown to reduce the return of fear. Here, we will establish the mechanism of return of fear after treatment, and its prevention, across systems, cognitive, and behavioral levels. Fear conditioning and extinction are a widely used laboratory model of exposure therapy for anxiety. In prior work, we showed robust individual differences in spontaneous recovery of fear after extinction and developed a computational model that explains spontaneous recovery as resulting from selective remembering of adverse events. Here, we aim to provide 1) direct evidence for selective remembering of adverse events as a mechanism of return of fear after extinction, 2) evidence that spacing and retrieval cues reduce spontaneous recovery by reducing the relative advantage of memories of adverse events and 3) evidence that this same mechanism underlies the effect of the clinical interventions on symptoms of anxiety. We will achieve these aims through three randomized-controlled studies assessing selective remembering and spontaneous recovery after extinction behaviorally, using MEG imaging, and clinically.