Targeted memory reactivation for enhancing exposure therapy

Abstract

Prior research has demonstrated that memory consolidation can be enhanced by coupling learning with an olfactory or auditory contextual cue, then presenting that cue again during subsequent sleep. This process, known as targeted memory reactivation (TMR), has been investigated in basic research but has not been translated into clinical application. The current study investigated whether TMR could be used to augment exposure therapy by promoting consolidation of extinction learning. 109 participants with marked fear of spiders, contamination, or enclosed spaces were given standardized in-vivo exposure therapy in the presence of a contextual odor. Following treatment, they were randomized to one of three conditions: (1) EXPCUE, involving sleep in the presence of the contextual odor previously presented during exposure, (2) NOVCUE, involving sleep in the presence of a novel odor, or (3) CNTL, involving sleep without any odor. Electrodermal and fear responding to behavioral approach tests, as well as self- reported anxiety and disgust, were assessed at baseline, post-treatment, one-week, and one-month follow-up visits. We predicted that at follow-up the EXPCUE condition would exhibit lower anxiety than the NOVCUE and CNTL conditions, and that self- reported peak anxiety during the last exposure trial would moderate the relationship between condition and anxiety at follow-up. These hypotheses were not supported, as there were no between-group differences in primary outcomes and the predicted moderation effects were not observed. In contrast to hypothesis, the EXPCUE group exhibited a reduced rate of anxiety decrease in comparison to the NOVCUE or CNTL conditions as measured by self-report questionnaires. Results suggest that TMR does not enhance consolidation of extinction learning during exposure therapy.