Can imagery rescripting and imaginal extinction attenuate the return of conditioned fear?

Standard extinction (SE) is the most widely implemented intervention for reducing conditioned and generalized fear, indexed by psychophysiological skin conductance responses, and subjective self-report responses such as expectancy and valence ratings; however, the possibility of fear return still remains. Hence, novel interventions may be used to augment the efficiency of SE. Imagery rescripting (ImRS), based on the premise of unconditioned stimulus (UCS) devaluation, encompasses the devaluation of the cognitive representation of the UCS in a positive direction. Imaginal extinction (IE), based on the principles of UCS expectancy evaluation, involves vivid imagination of the conditioned stimuli during extinction. In the current study, we compared the efficacy of imagery rescripting + extinction, imaginal extinction, and standard extinction in attenuating the return of conditioned and generalized fear. Seventy-two healthy individuals were randomly assigned to ImRS, IE, or SE groups. Day 1 comprised the fear acquisition and generalization phases. On day 2, the intervention and generalization testing phases were conducted. On day 15, the return of fear due to spontaneous recovery was assessed. Our study is the first known to compare the efficacy of ImRS and IE in attenuating the return of generalized fear response. We found that the three interventions effectively attenuated conditioned responses on Day 15, highlighting a potentially distinct effect of imagery rescripting on UCS devaluation. The current study therefore provides preliminary evidence that combining imagery rescripting with extinction may influence both expectancy-based and evaluative aspects of conditioned fear, as compared to imaginal extinction and standard extinction.