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Modular Motion assisted Memory Desensitization and Reconsolidation (3MDR)

Why is a new treatment needed?

Over the past 20 years, a number of treatments have been shown to result in clinically meaningful improvements for many military personnel and veterans with PTSD.

These include trauma-focused interventions Cognitive Processing Therapy (CPT) and Prolonged Exposure (PE).  

Unfortunately, these and other first-line treatments do not help every PTSD sufferer and many continue to experience distressing symptoms despite having received the best-evidenced treatments currently available.  

It is, therefore, vital that better treatments are developed for military personnel and veterans suffering from treatment-resistant PTSD.

What is 3MDR?

Modular Motion assisted Memory Desensitization and Reconsolidation (3MDR) is a new treatment, developed in The Netherlands, that incorporates key elements of successful treatments such as Virtual Reality Exposure (VRE) and Eye Movement Desensitization Reprocessing (EMDR) and adds motion through walking on a treadmill.

Exposure to self-selected images of deployment, enhanced with walking, music and emotion-provoking pictures aims to eliminate avoidance during exposure and promote presence.

Participants walk a repetitive cycle whilst talking and viewing their images.

This is an important distinction between 3MDR and traditional trauma-focused techniques as patients learn to move through their avoidance and face their fears by, literally, approaching their traumatic memories.

The treatment uses the Motek Gait Real-time Analysis Interactive Lab (GRAIL) system with its dual-belt treadmill, motion-capture system, and synchronized Virtual Reality (VR) environment, which comprises a 180° projection screen with four projectors and a surround sound system.

How does it work?

No-one knows exactly how 3MDR works and it is likely that similar mechanisms to other trauma-focused interventions are involved.

In addition, it is hypothesised that by introducing dual tasks (for example, walking and viewing images) that use working memory resources, there is less memory available for other memory processes, making the recollection of memories less vivid and less emotional.

​Preliminary results from research conducted by the originators of 3MDR in the Netherlands regarding the efficacy of 3MDR in veterans with treatment-resistant, combat-related PTSD are promising, with a decrease in PTSD symptoms and no dropout rates.

Who took part?

Participants were aged 18 or over, had provided informed consent, meet DSM5 criteria for combat-related PTSD and treatment-resistance.

This was defined as having received prior trauma-focused psychological treatment without loss of PTSD diagnosis.​

What did the study involve?

  • ​A phone call from a member of the research team to check eligibility, discuss the details of the study, and answer any questions.
  • Participants gave informed consent and then self-monitored their symptoms on a daily basis for two weeks.
  • Face-to-face interviews took place with a researcher at Cardiff University to explore participants’ backgrounds, experiences and trauma-related symptoms, supplemented by self-completed questionnaires.
  • The 3MDR therapy was delivered weekly over nine weeks (two weeks preparation, six weeks 3MDR and one concluding session) by experienced psychological therapists. Participants were randomly allocated to receive 3MDR therapy immediately or after a wait of 12 weeks.
  • Follow-up interviews, involving similar questions, were conducted at 12 weeks and 26 weeks after randomisation.

The Cardiff University 3MDR study finished in May 2020.

For more information, please visit the resources below.

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