Attenuating fearful memories through modulation of learning: Effects of modified consolidation and cued extinction on intrusions

Abstract

Exposure-based therapies for PTSD are thought to reduce intrusive memories through extinction processes. Methods that enhance extinction may translate to improved treatment. Rat research suggests cueing a memory with a conditioned stimulus (CS) cue and then modifying the retrieved memory within a specific reconsolidation window, enhances extinction. In humans, two studies (Schiller et al., 2010; Kindt & Soeter, 2013) using basic learning paradigms show discrepant findings. Using a distressing film paradigm, participants (N = 148) completed fear acquisition and extinction. At extinction, they were randomized to: CS cue within reconsolidation window; CS cue outside window, or non-CS cue within window. Intrusions were assessed 24 hr after extinction. Participants receiving the CS cue and completing extinction within the reconsolidation window had more intrusions (M = 2.40, SD = 2.54) than those cued outside (M = 1.65, SD = 1.70) or those receiving a non-CS cue (M = 1.24, SD = 1.26), F(2,145) = 4.52, p = .01, d = 0.55. Consistent with the reconsolidation hypothesis, presenting a CS cue does appear to activate a specific period of time during which a memory can be updated. However, the CS cue caused increased rather than decreased frequency of intrusions. Understanding parameters of pre-extinction cueing may help us better understand reconsolidation as a potential memory updating mechanism.