The Effect of Dual Attention in an EMDR Intervention

Research to date indicates that trauma-focused treatments are safe and effective for PTSD, even when higher-risk comorbidities (e.g., psychosis or substance use) are present. In particular, there are data pointing to the efficacy of prolonged exposure therapy and eye movement desensitization and reprocessing (EMDR) therapy. Clinical practice guidelines specifically recommend trauma-focused treatment with exposure and/or cognitive restructuring components. Regarding EMDR interventions, there are increasing results supporting its efficacy. Some interesting clinical advantages presented by EMDR as opposed to cognitive-behavioral therapies are 1) the efficacy found despite less exposure to the traumatic memory, 2) the exclusion of homework, 3) as well as the rapid reduction in subjective disturbance produced even after a single session of EMDR therapy. However, the mechanisms producing the improvement and, in particular, the effect of bilateral stimulation are not precisely known. More research is needed in this regard since bilateral stimulation is the most controversial part and with less evidence found. In addition to this, there are very few studies that have analyzed the differential efficacy of the presence or absence of bilateral stimulation or of the different types of stimulation possible. As for the comparison between types of stimulation (bilateral with eye movements, or focusing on a fixed point), greater treatment effects have been found for EMDR with fixation on an immobile hand compared to eye movements. The aim of this study is to examine the effectiveness of a comprehensive intervention protocol for people who have experienced traumatic events and present post-traumatic symptomatology. In addition, this study will compare the efficacy of traumatic memory processing with and without dual attention.

The protocol will be developed following the three stages of recovery from trauma: first, focusing on establishing the therapeutic alliance and safety; second, focusing on recounting and re-processing the traumatic event; and third, focusing on reconnecting with others and with life despite the trauma experienced. This study will analyze the differences of type of traumatic processing; 1. using bilateral stimulation, 2. using fixed-point focusing and 3. closing the eyes (only exposure to the traumatic memory, without dual attention).