"A 2014 meta-analysis of clinical trials showed that the therapeutic technique known as eye movement desensitization and reprocessing (EMDR) can reduce symptoms of post-traumatic stress disorder (PTSD). The meta-analysis also established that longer durations of EMDR treatment correlated with better outcomes.
The meta-analysis by Ying-Ren Chen and colleagues in the journal PLOS One evaluated 26 randomized controlled trials of EMDR in people with PTSD. Chen and colleagues found that EMDR reduced PTSD symptoms, depression, anxiety, and subjective distress.
EMDR is a psychotherapeutic technique intended to reduce the distress that a patient feels about a traumatic memory. The patient is encouraged to recall the traumatic event while focusing on an external stimulus. Typically this would mean using their eyes to track the therapist’s hand moving back and forth from left to right. This process can help patients reprocess the trauma and alleviate the stress that they feel upon recalling the traumatic memory.
Chen and colleagues found that EMDR sessions that lasted longer than one hour were more effective than those that lasted less than an hour. Another finding that was that groups led by therapists who were experienced in PTSD group therapy were more effective than groups led by therapists without that experience.
Other more recent research has established that traumatic memories can be reprocessed or even extinguished by making use of the memory reconsolidation window. Five minutes to one hour after a patient engages in active emotional recall of a traumatic memory, a window of time opens in which that memory is subject to reinterpretation and revision.
An experienced therapist can create a safe environment for a patient to recall traumatic events and find alternative ways of interpreting the experience—for example, by focusing on their strength in surviving the experience. This process resembles EMDR in many ways, but without the eye movements.
In a 2017 article in the journal Psychiatry Research, BNN Editor-in-Chief Robert M. Post and colleague Robert Kegan discuss the possibility of using the reconsolidation window to reprocess stressors that led to a depressive episode."