EMDR therapy changes the brain. EMDR therapy has been recognized as an evidence-based method for over a decade.

Research has shown EMDR-related neurobiological changes in the brain during therapy itself via EEG imaging which was the first time in which neurobiological changes occurring during any psychotherapy session had been reported, making EMDR the first psychotherapy with a proven neurobiological effects. 

The effectiveness of EMDR in the treatment of PTSD had been supported by SPECT studies, which have shown that after comparing the brain activity before and after therapy. The results of these studies indicate a post-treatment reversal of the prefrontal and limbic abnormalities found in patients with PTSD.

Source: Correlates of EMDR Therapy in Functional and Structural Neuroimaging: A Critical Summary of Recent Findings in the Journal of EMDR Practice and Research Jan 2013