Until recently, psychologists thought trauma permanently altered brain chemistry. We now believe that eye movement somehow liberates the natural healing process to reverse such effects. It seems that eye movement stimulates the neurochemical communication between the two hemispheres of the brain, which results in the trauma no longer containing the negative emotional charge that was originally associated with it.
Researchers in the Human Resource Institute’s Trauma Center (Brookline, MA) have been using SPECT brain-scan imaging to map changes that occur from EMDR treatments. They found that traumatic material appears to be held in the right parietal region, which is concerned with body states and is mostly nonverbal. Following EMDR, areas of the left frontal regions that have to do with verbal processing and future planning come back online. Although the brain has a natural mechanism for processing disturbing events, when a traumatic experience is overwhelming, the brain may not be able to process it in the same way. This is why severely traumatized people often find themselves struck with disturbing memories long after the traumatic event. Research suggests that an important part of the natural trauma processing happens during rapid eye movement (REM) sleep, which provides alternating stimulation of the right and left hemispheres of the brain. This may help explain why EMDR therapy seems to jump-start the brain’s natural healing ability, allowing the traumatic memory to become less and less disturbing.
EMDR is now the most researched treatment for Posttraumatic Stress Disorder (PTSD), and many scientific studies have shown it is effective and long-lasting. For example in December 1995, a study by Wilson, Becker, and Tinker was published in the Journal of Consulting and Clinical Psychology, where 80 subjects diagnosed with PTSD showed significant improvement after EMDR therapy. Treatment benefits were unchanged at a 15-month follow-up.
Access to a current list of EMDR related research citations can be found online at:
Some additional research resources include:
For more EMDR research information, contact the EMDR International Association (EMDRIA; www.emdria.org).