1. The study

A Dutch and British team, Suzy J.M.A. Matthijssen (Altrecht GGz & Utrecht University), Thomas Brouwers, Celeste van Roozendaal, Tessa Vuister and Ad de Jongh (ACTA Amsterdam, Salford University, University of Worcester), published this research in 2021 in the European Journal of Psychotraumatology (Matthijssen et al., 2021).

EMDR 2.0 differs from the standard protocol in three main enhancements: (1) explicitly motivating the patient to actively hold the memory in working memory, (2) maximising the load on working memory by combining several simultaneous tasks (variable eye movements, counting, tapping, smells, tastes, verbal surprises), and (3) inducing arousal through hand claps or sudden gestures. The hypothesis was that more intense taxing of working memory would speed up reprocessing and reduce the number of sets required.

3. Where its conclusions stop

This study is methodologically sound (preregistered, randomised, with Bayesian analyses), and its conclusions should be read within their limits.

• Non-clinical sample. The participants did not have PTSD. They had chosen a disturbing memory, without meeting diagnostic criteria. Traumatic memories in patients with PTSD are generally more resistant and more avoided, and require more sets; this is precisely the situation for which EMDR 2.0 was developed. Generalisation to clinical practice therefore remains a hypothesis still to be demonstrated.
• Single session of up to 20 minutes. In clinical practice, sessions last 50 to 90 minutes, often over several appointments. This time constraint makes it impossible to measure real differences in efficiency on complex traumatic memories that would resist rapid resolution.
• No check that the memory was held in working memory. EMDR 2.0 relies on patients’ ability to actively keep their memory in mind while carrying out complex tasks. This was not checked: some participants in the EMDR 2.0 group said they had been glad to concentrate on the tasks so as to stop thinking about the memory, which suggests that some were unable to keep it in mind.
• Follow-up limited to 4 weeks. The effects at 4 weeks are stable in both groups, and nothing is known beyond that point. For real trauma, durability at 6 or 12 months would be essential to document.
• “More effective” should be read with care: on clinical outcomes, EMDR 2.0 performed on a par with standard EMDR. On the reduction of SUD and vividness, the two protocols are equal. EMDR 2.0’s advantage lies in efficiency (fewer sets for the same result), with equivalent effectiveness.

These results are consistent with the literature on working memory theory applied to EMDR (Van den Hout & Engelhard, 2012, link) and with previous studies showing that more intense working-memory taxation produces larger decreases in memory emotionality.

Clinical vignette

Fictional case, built from common clinical situations.

Isabelle, 42, seeks help for post-traumatic stress following a car accident three years earlier. She has had several cycles of standard EMDR without managing to bring the SUD on the core memory below 6. In session, she describes a tendency to “switch off” mentally as soon as the eye movements begin, a classic dissociative avoidance phenomenon that the therapist recognises as a major obstacle to reprocessing.

Having read the research on EMDR 2.0, the therapist decides to integrate elements of the enhanced protocol: he begins by explicitly motivating Isabelle to actively hold the image of the accident in mind during the tasks, then introduces sets combining diagonal eye movements, counting under her breath and, occasionally, a brief and unexpected hand clap, the principle of which he has explained to her beforehand, with her agreement. The effects are noticeable from the second enhanced session: Isabelle reports lower vividness and a SUD down to 3, and above all describes, for the first time, a sense of “distance” from the traumatic image.

This case illustrates the use of EMDR 2.0 as a second-line option for resistant patients, alongside standard EMDR as the usual approach. Had Isabelle also presented with structural dissociation, the therapist would have prioritised strengthened stabilisation before increasing the load on working memory, as overload can paradoxically encourage dissociation in the most vulnerable profiles.

Frequently asked questions

Should I switch to EMDR 2.0 for all my patients?

Standard EMDR remains the first-line choice. This study compares the two protocols only in non-clinical participants with negative memories. To date, no data justify replacing standard EMDR with EMDR 2.0 as a first-line treatment for patients with PTSD. EMDR 2.0 is an option worth exploring, particularly for patients who respond little or insufficiently to classic EMDR: an individualised clinical decision rather than a systematic change of protocol.

Is EMDR 2.0 suitable for all trauma profiles?

The question remains open. The authors state that EMDR 2.0 was developed for patients who actively avoid activating their traumatic memory. This trial, conducted with volunteers, leaves open the question of dissociative profiles: as a matter of clinical prudence, appropriate preparation remains advisable before increasing the load on working memory in these patients. Clinical caution is therefore called for with patients presenting with significant dissociation, severe complex PTSD or associated personality disorders.

What is a “set” in EMDR, and why does the number of sets matter?

A set is a sequence of bilateral stimulation (around 30 seconds of eye movements, tapping or auditory stimulation) during which the patient simultaneously holds the traumatic memory in mind. Each round begins with a return to the target and ends when the patient reports no new associations. The number of sets is an indicator of efficiency: fewer sets for the same result potentially means less exposure time and a reduced emotional burden, which can be decisive for patients who struggle to tolerate the procedure.