What is EMDR therapy?

EMDR stands for Eye Movement Desensitisation and Reprocessing, which is a mouthful, and the name is arguably the least helpful thing about it. It sounds clinical and slightly gimmicky, and it puts the eye movements front and centre when the eye movements may be the least important part.

Here is the plain version.

EMDR is a structured therapy for trauma. You bring to mind a distressing memory, briefly and in a controlled way, while doing something that divides your attention, usually following your therapist's fingers moving side to side. You do this in short bursts, pausing between each one to notice what has shifted. Over a number of these bursts, the memory tends to lose its charge. It stays true. It stops hurting the way it did.

That is the whole thing, mechanically. Everything else is detail, caveat and argument, and there is a lot of all three.

Where it came from

The origin story is genuinely unusual, and it matters, because it shapes why the therapy is both widely used and widely argued about.

In 1987, a psychologist named Francine Shapiro was walking through a park, turning over some troubling thoughts, when she noticed that the thoughts seemed to lose their intensity. She realised her eyes had been moving rapidly back and forth. She went away and tested the effect deliberately, first on volunteers, then in a controlled study of people with trauma symptoms, published in 1989.

She called it EMD, for Eye Movement Desensitisation. A couple of years later she renamed it, adding the Reprocessing, because it had become clear that something more than simple desensitisation was going on. People were not just becoming less reactive to the memory. They were arriving at new insights about it, shifts in how they understood themselves.

Most therapies are built from a theory and then tested. EMDR was noticed first, on a walk, and had its theory attached afterwards. That sequence is the root of a lot of the scepticism that still surrounds it, and I have written about that scepticism separately, because it deserves its own piece rather than a paragraph here.

The idea underneath it

EMDR's explanation for itself is called the Adaptive Information Processing model, and you do not need the jargon to grasp it.

The claim is that the brain has a natural system for digesting experience. Something happens, the brain processes it, extracts what is useful, files it as a memory, and lets the distress fade. Most of the time this works so well you never notice it.

A traumatic event can overwhelm that system. When it does, the memory does not get filed properly. It stays stored in something close to its raw state, still carrying the images, the beliefs, the emotions and the physical sensations that were present at the time.

That is why a trauma memory does not behave like an ordinary memory. An ordinary bad memory is unpleasant to recall. A trauma memory can drop you straight back into the event, complete with the racing heart and the fear, triggered by a smell or a sound or a particular quality of light. On this model, that is because the memory is not in the past. It never got put there.

EMDR, in this account, is a way of switching the digestion system back on for a memory that got stuck, so the brain can finish a job it started and could not complete. The memory remains. What changes is that it becomes something that happened to you, rather than something that is still happening.

Whether that model is correct, and in particular whether the eye movements are doing anything special, is contested. I will come back to it.

What actually happens: the eight phases

EMDR is delivered in eight phases. That sounds bureaucratic, but only three of them are the processing itself. The rest is what makes the processing safe, and skipping it is where harm happens.

The first two phases are history and preparation. Your therapist takes a full history, works out what is actually driving the problem, and draws up a list of memories to target. Then, crucially, they build your capacity to cope with difficult feeling: a mental calm place you can retreat to, grounding techniques, ways of bringing yourself back down. This can take one session or many, and for people with severe or complex trauma it can take a long time. It is not a preamble. It is the foundation.

The middle phases are the work. You pick a specific memory, identify the worst image, name the negative belief it left you with ("I am powerless", "it was my fault", "I am not safe"), and name the belief you would rather hold instead. You rate how disturbing the memory feels right now, and then you begin the sets of bilateral stimulation, holding the memory in mind while your attention is divided. You pause, say what you noticed, and go again, until the distress drops away. Then you strengthen the positive belief, and scan your body for any physical residue and process that too.

The final phases are closure and reevaluation. Closure brings you back to a settled state before you leave the room, every time, whether or not the memory is finished. Reevaluation is the start of the next session, where your therapist asks what came up during the week, because the brain carries on processing between sessions and what surfaces becomes the next piece of work.

If you want the detailed walk-through of the phases and the competing theories of why it works, I have written a fuller piece on how EMDR works. This is the overview.

The bilateral stimulation, briefly

The side-to-side eye movements are the famous part, but they are not the only option. The same alternating, left-right stimulation can be delivered as taps on your hands or knees, or as tones alternating between your ears through headphones. Some people close their eyes and use sound or touch. Your therapist should tailor this to you.

This flexibility is also why EMDR adapts reasonably well to video calls, which I have covered separately.

What it is used for

EMDR was built for PTSD, and PTSD is where the evidence is genuinely strong. It is recommended by NICE and by the World Health Organisation, it is available on the NHS, and it is supported by a large body of randomised controlled trials. For a single traumatic event in an otherwise stable adult, it can work remarkably fast, sometimes in a handful of sessions.

It is now offered for a great deal more than PTSD: depression, anxiety, phobias, OCD, eating disorders, addiction, grief, low self-esteem. Some of this may prove justified. Much of it currently runs ahead of the evidence, resting on the assumption that if a condition has trauma underneath it, and most conditions can, then EMDR should help.

My honest advice is to be more sceptical the further you get from trauma. The evidence base for PTSD is not the evidence base for OCD or eating disorders, and anyone who quotes you EMDR's PTSD credentials while selling you EMDR for something else is blurring a line that matters. I have written separate pieces on several of these applications, each trying to say plainly where the evidence actually sits.

The honest caveat about the eye movements

You should know this up front, because you will meet it eventually.

There is a real, ongoing scientific argument about whether the eye movements, the thing the therapy is named after, actually do anything. Studies that strip out the eye movements and keep everything else have often found little difference. Critics argue that EMDR works because of the things it shares with other trauma therapies, controlled exposure to the memory, changing the belief attached to it, a structured and contained process, a good therapeutic relationship, and that the finger-waving is decoration.

This is not a fringe objection and I take it seriously. But notice what it does and does not undermine. It is a serious problem for the theory. It is not a reason to avoid the treatment. The trials measure the whole package, and the whole package reduces PTSD symptoms about as well as the leading alternative. If it turns out the active ingredients are the ordinary ones, the treatment still works by the same amount.

So the fair summary is this: EMDR works for trauma, we are not certain why, and the part it is named after may not be the part that matters.

Is it right for you?

If you have PTSD, particularly from a single event, EMDR is a well-evidenced, NHS-available option worth discussing with your GP, and some people find it more tolerable than therapies that require them to narrate the event aloud in detail.

If you have complex or childhood trauma, EMDR can help, but the preparation matters enormously and you want a therapist experienced with dissociation, not just anyone with an EMDR certificate.

If you are considering it for something other than trauma, go in with your eyes open about how thin the evidence may be, and ask what the first-line treatment is before you commit.

And in all cases, the quality of the therapist matters more than the label on the therapy. A good EMDR therapist spends real time on the first two phases before any eye movements happen, has a plan for when things get difficult, and wants to hear honestly how your week actually went. If someone rushes you to the eye movements because that is the exciting bit, that is the warning sign to watch for.

EMDR therapy is not magic, and it is not a gimmick. It is a structured, effective trauma treatment with a strange origin, a contested mechanism, and a genuinely good track record in the one area it was built for. Knowing all three of those things at once is the honest starting point.

This is general information, not clinical advice. If you are considering EMDR, speak to your GP or an accredited EMDR therapist about whether it suits your situation. If you are in crisis, contact NHS 111 or Samaritans on 116 123.

References

Boardman, M., & Schwartz, A. (2023). The EMDR Workbook for Trauma and PTSD. New Harbinger Publications.

Brayer, R. (2023). The Art and Science of EMDR: Helping Clinicians Bridge the Gap. PESI Publishing.

Croitoru, T. (2014). The EMDR Revolution: Change Your Life One Memory at a Time. Morgan James Publishing.

National Institute for Health and Care Excellence. (2018). Post-traumatic stress disorder (NG116). https://www.nice.org.uk/guidance/ng116

Shapiro, F. (2017). Eye Movement Desensitization and Reprocessing (EMDR) Therapy: Basic Principles, Protocols, and Procedures (3rd ed.). Guilford Press.

World Health Organization. (2013). Guidelines for the management of conditions specifically related to stress. WHO.