Applying the peak-end rule to improve exposure outcomes in fear and anxiety

This study investigates whether the peak-end rule, i.e. biased retrospective evaluations of affective episodes being most strongly influenced by the peak and end intensity, applies to a brief exposure episode involving a fear-evoking stimulus. Thirty-six spider-fearful participants underwent a virtual reality exposure episode to a spider, which ended with either high or low fear levels. Consistent with the peak-end rule, participants whose episode ended with low fear retrospectively rated the episode as less unpleasant and frightening and, at follow-up, reported greater willingness to re-experience it. They also showed reduced avoidance behaviour, particularly in a VR-based behavioural approach task. These findings provide preliminary support for applying the peak-end rule to optimise exposure-based interventions. Ending exposure sessions with lower fear may enhance patients' retrospective evaluations and willingness to re-engage, potentially improving treatment adherence. Future research should investigate whether these effects can be replicated in full-length exposure sessions and whether they contribute to long-term therapeutic efficacy.