Agenda

Outcome studies and stringent meta-analyses show that EMDR is effective in the treatment of PTSD. Observations from controlled laboratory experiments corroborate the clinical findings. Making eye movements during recall of an aversive memory reduces its vividness and emotionality; not only during recall+eye movements, but also during later recollections, without eye movements.

We took the opportunity to experimentally test some hypothesis about how EMDR works. The findings are surprisingly consistent. First, effects of EMDR are not merely due to imaginary exposure: a short period of “recall only” does not affect negative memories, but a short period of “recall+ eye movements” does. Second, proponents of EMDR suggest that the bilateral stimulation, inherent in horizontal eye movements, is essential. Data indicate it is not. Vertical eye movements are as effective as horizontal eye movements. Furthermore,  various ‘dual tasks” that do not involve eye movements do the same job. Working memory theory provides a third explanation. It survived a series of critical tests. Data have implications for e.g. the indication of EMDR, the use of auditory stimulation vs. eye movements, eye movements during the recall of positive memories, individual differences in the impact of eye movements etc. In the key note, we will clarify conceptual notions, present data from laboratory and clinical studies and suggest implications that are potentially surprising and clinically relevant.

Dr. Marcel van den Hout is professor at the faculty of Social Sciences of Utrecht University, department of Clinical and Health Psychology