P020 Exploring the Roles of Individual Rapid Eye Movement Sleep Parameters in Emotional Memory Processing

Abstract Background Maladaptive emotional memory processing is thought to underpin intrusion symptoms experienced by individuals with post-traumatic stress disorder (PTSD). Curtailment of rapid eye movement sleep (REMS) impairs emotional memory consolidation (EMC) and is proposed to contribute to the development of PTSD. However, the effects of altered REMS quality remain less explored. The present study aims to investigate the potential ability of REM percentage, REM latency, and REMS fragmentation to predict EMC. Methods The study forms part of a larger study investigating the effects of suvorexant and temazepam on REMS and EMC. Healthy participants view a series of emotionally positive, negative and neutral images, undergo overnight polysomnography with a study drug or placebo, and are assessed for recognition 48 hours after viewing the images. REMS architecture metrics are derived from polysomnographic data. EMC is calculated based on signal detection theory (d′ = z(hit rate) − z(false alarm rate)). Results Data collection is ongoing with 11 participants’ data being collected. A one-way ANOVA reveals a main effect of valence, with positive and negative images being recognised better than the neutral (p(positive-neutral) = .039, p(negative-neutral) = .039). REMS parameters do not significantly predict EMC when accounting for image valence, possibly due to low statistical power. Discussion Given existing literature supporting the contribution of REMS on emotional memory processing, promoting high-quality REMS may help facilitate adaptive EMC. Further data is required to examine this effect.