It doesn't sound like it should work. You're not even saying much to the therapist. You're just picturing an image or "movie" of a traumatic event in your life while you move your eyes back and forth. Yet it's making news for achieving remarkable results for survivors of trauma, such as Prince Harry.
What I'm describing is eye movement desensitization and reprocessing (EMDR) therapy. And it's your eyes moving back and forth, or both hands tapping your shoulders in Prince Harry's case, that researchers believe is the key to helping your brain finally allow you to move on from the most emotionally painful moments of your life. The scientific name for it is bilateral stimulation, meaning stimulating both sides of the body.
Researchers believe EMDR stimulates both hemispheres of the brain and recreates conditions similar to when we're sleeping, when the brain processes memories. EMDR appears to help a client relax enough that the traumatic memory can leave the "fight, flight or freeze" part of the brain and be put away in "long-term storage," where it's not as vivid.
I've had clients who've been "stuck" for years reliving a trauma in their mind be able to move on. They notice progress after just a few sessions. Teenagers, from what I've observed, seem to make progress the fastest.
EMDR is widely used among therapists in Washington State. It's also recommended by the VA for service members returning from war zones. "EMDR has the strongest recommendation for being an effective treatment...of PTSD," according to the VA's National Center for PTSD.
An EMDR client in Wisconsin talked with his local TV station about how the therapy worked for him. Please note: He discusses surviving childhood domestic violence at the beginning of the video.
Prince Harry undergoes EMDR therapy on-camera
in this image from his Apple TV+ program The Me You Can't See. His form of bilateral stimulation is tapping his shoulders.