||Background: Posttraumatic stress disorder (PTSD) may develop after exposure to a traumatic event. Eye Movement
Desensitization and Reprocessing (EMDR) is an evidence-based psychological treatment for PTSD. It is yet unclear
whether eye movements also reduce stress reactivity in PTSD patients. This study aims to test whether eye
movements, as provided during Eye Movement Desensitization (EMD), are more effective in reducing stress
reactivity in PTSD patients as compared to a retrieval-only control condition.
Methods: The study includes participants who meet criteria of PTSD of the public psychological services in Jakarta
and Bandung, Indonesia. One hundred and ten participants are randomly assigned to either an (1) Eye Movement
Desensitization group (n = 55) or (2) retrieval-only control group (n = 55). Participants are assessed at baseline (T0),
post-treatment (T1), 1 month (T2), and at 3 months follow-up (T3). Participants are exposed to a script-driven
imagery procedure at T0 and T1. The primary outcome is heart rate variability (HRV) stress reactivity during scriptdriven imagery. Secondary outcomes include heart rate (HR), pre-ejection period (PEP), saliva cortisol levels, PTSD
symptoms, neurocognitive functioning, symptoms of anxiety and depression, perceived stress level, and quality of
Discussion: If the EMD intervention is effective in reducing stress reactivity outcomes, this would give us more
insight into the underlying mechanisms of EMDR’s effectiveness in PTSD symptom reduction.
Trial registration: ISRCTN registry ISRCTN55239132. Registered on 19 December 2017.