Eye-Movement does not reduce ratings of vividness and emotionality or the number of intrusive thoughts of unpleasant memories: Implications for Eye-Movement Desensitisation and Reprocessing (EMDR)

Eye-Movement Desensitisation and Reprocessing (EMDR) is a psychotherapy that incorporates the use of saccadic Eye-Movements (EM) to alleviate distress caused by traumatic memories. Although EMDR is recognised as a front-line treatment for individuals suffering from Posttraumatic Stress Disorder (PTSD), the mechanisms underlying the efficacy of the EM component remain a point of contention. The aim of the current research was to investigate first, whether EM reduced ratings of memory vividness and emotionality by taxing Working Memory (WM) capacity, and second, to examine whether EM lowered the number of intrusive thoughts under two opposing suppression conditions. In two experiments, 244 non-clinical participants were asked to recall an unpleasant memory while simultaneously engaging in fast-EM, slow-EM or a no-EM control. Participants then received an instruction to intentionally avoid thinking about the memory, or to think about whatever came to mind. Relative to no-EM, fast-EM and slow-EM had no significant effect on vividness and emotionality ratings, nor did they influence the number of intrusive thoughts. In addition, the level of suppression intent had no impact on memory outcomes. Overall, the results from these two experiments oppose earlier findings in support of WM theory, and a significant body of research that has demonstrated the efficacy of the EM component. Implications for the EM component in EMDR are discussed, and an alternative explanation for EM is offered.