Prepared by the Couples TLC Editorial Team | Clinically reviewed by Jack S. Gershfeld, LMFT
Francine Shapiro was walking through a park in 1987, turning over some distressing thoughts, when she noticed that her eyes were moving rapidly from side to side and that the thoughts had lost some of their charge. Most people would have filed this under odd and continued the walk. Shapiro, then a doctoral student, went home and started testing it on other people.
That origin story is repeated so often in EMDR training that it has taken on a slightly mythical quality, and it does the treatment a certain amount of damage. It sounds accidental. It sounds like something someone made up. And the mechanism, when you first hear it described, sounds implausible enough that a fair number of intelligent people dismiss the whole thing before they get to the part that matters, which is that the treatment has since accumulated one of the larger evidence bases in trauma psychology and is recommended for post traumatic stress disorder by the World Health Organization, the American Psychological Association, the UK’s National Institute for Health and Care Excellence, and the Department of Veterans Affairs.
You can be skeptical about why EMDR works while accepting that it does. Quite a few researchers occupy exactly that position.
What the treatment is actually for
EMDR stands for eye movement desensitization and reprocessing, and it is designed to address a specific problem: memories that have not been filed correctly.
The working theory, which Shapiro called adaptive information processing, is that the brain has a natural system for metabolizing difficult experience, in much the same way that the body has a system for healing a wound. Most bad experiences get processed. They lose their sensory intensity, they get connected to other knowledge, and they settle into the past tense.
Traumatic memories sometimes do not. They stay stored in something close to their original state, with the raw sensory and emotional content intact and unlinked to the rest of what the person knows. This is why a flashback does not feel like remembering. It feels like happening. The memory has never been updated with the information that it is over.
EMDR aims to restart the processing that got stuck. The target is not the event itself, which cannot be changed, but the way the memory is stored and the beliefs about the self that got encoded alongside it.
The eight phases, described honestly
EMDR is often reduced in popular description to “the eye movement thing,” which understates it considerably. The protocol has eight phases and the eye movements occupy a fraction of the total time.
History taking and treatment planning. The therapist builds a picture of the person’s history and identifies specific memories to target, along with present triggers and future situations the person wants to handle differently. In complex cases this phase alone can take several sessions.
Preparation. This is the stabilization phase, and it is the one that gets rushed by inexperienced practitioners and rushed by clients who want to get to the real work. It involves building resources: grounding techniques, a calm place exercise, containment strategies, and enough of a therapeutic relationship that the person can tolerate what is coming. For someone with a single incident trauma this might take one session. For someone with a childhood abuse history it might take months, and that is appropriate rather than a delay.
Assessment. The therapist and client identify the specific components of the target memory: the worst image, the negative belief attached to it, the preferred belief, the emotion, and where it is felt in the body. Baseline ratings are taken for how disturbing the memory feels and how true the positive belief feels.
Desensitization. This is the phase with the bilateral stimulation. The client holds the memory in mind while following the therapist’s fingers with their eyes, or receiving alternating taps, or listening to alternating tones. Sets are short. Between sets, the therapist asks what came up, and the client reports whatever surfaced, which might be an image, a sensation, a thought, or another memory entirely. The therapist mostly stays out of the way and lets the associative process run.
Installation. The preferred belief is strengthened and paired with the memory.
Body scan. The client checks for residual physical tension associated with the memory, since somatic residue often remains after the cognitive and emotional charge has dropped.
Closure. Every session ends with the client stabilized, whether or not the target was fully processed.
Reevaluation. The next session begins by checking what has held.
What the bilateral stimulation is doing
Nobody knows for certain, and any source that tells you otherwise is overselling.
The two leading explanations are worth knowing. The working memory hypothesis holds that following a moving target taxes working memory capacity while the person simultaneously holds a vivid memory in mind. Because the two tasks compete for limited resources, the memory becomes less vivid and less emotionally intense, and it is then re-stored in that weakened form. There is solid experimental support for this, including studies showing that other demanding dual tasks produce similar effects.
The orienting response hypothesis proposes that the eye movements trigger an investigatory reflex that, on finding no actual threat, produces a relaxation response, allowing the memory to be processed in a physiologically calmer state.
There is also a longstanding debate about whether the bilateral stimulation contributes anything beyond the rest of the protocol. Several dismantling studies have found comparable outcomes with and without the eye movements, which would suggest the active ingredients are exposure to the memory, the structured protocol, and the therapeutic relationship. Other studies have found the eye movements do add something. The question is not settled.
What is worth holding onto is that a treatment can be effective while its mechanism remains disputed. Lithium was used for decades before anyone could explain it properly.
Where the evidence stands
EMDR has been tested in a large number of randomized controlled trials and multiple meta-analyses. The broad picture is consistent. For post traumatic stress disorder arising from discrete, identifiable traumatic events, EMDR produces large reductions in symptoms and performs roughly on par with trauma-focused cognitive behavioral therapy, which is the other treatment with comparably strong support. Some trials find EMDR reaches results in fewer sessions, partly because it does not require homework or detailed verbal narration of the trauma.
That last point is clinically significant. For people who cannot bring themselves to describe what happened in words, and there are many, a treatment that does not require them to do so removes a real barrier.
The evidence for complex trauma, meaning prolonged and repeated interpersonal trauma usually beginning in childhood, is thinner and more cautious. This is not unique to EMDR. It is true across the trauma treatment literature. Standard protocols developed on single incident trauma do not transfer cleanly to someone with hundreds of overlapping events, a fragmented sense of self, and no memory of ever feeling safe. Practitioners working in this territory typically extend the preparation phase substantially, work within a phase-based framework, and accept a longer timeline. Anyone promising rapid resolution of a childhood abuse history in a handful of sessions is not describing responsible practice.
What EMDR does not do
Being clear about the limits is the fastest way to set expectations that will survive contact with the actual treatment.
EMDR does not delete memories. Clients routinely worry about this and it does not happen. What changes is the charge, not the content. People report remembering the event perfectly well while no longer being hijacked by it.
EMDR does not usually feel pleasant while it is happening. Processing sessions can be intensely emotional and people are often tired afterward. Material sometimes continues to surface between sessions.
EMDR does not repair a relationship. This is the limitation most relevant to anyone reading this as part of a wider inquiry into childhood trauma. Reprocessing a memory can reduce flashbacks and quiet the constant scanning that wears a person down, both of which help a marriage indirectly. It does not, on its own, change the pursue and withdraw cycle two people have been running for fifteen years. That pattern is interactional and lives between two nervous systems rather than inside one, which is why the damage childhood trauma does to adult love responds best to interventions aimed at the bond itself. The relational pattern is part of the wider effect of childhood trauma on adult relationships.
The research on attachment-based couple work makes this point from the other direction. Sue Johnson’s studies with couples affected by trauma, including the randomized trial led by Jane Dalton with female survivors of childhood abuse published in 2013, and the earlier work with Heather MacIntosh on childhood sexual abuse survivors, treated the relationship as the site of healing rather than as a bystander to individual recovery. Many people benefit from both approaches. Sequencing varies by person, and it is a reasonable thing to discuss openly with a clinician.
How to find a practitioner who knows what they are doing
Training quality varies more than most people expect. EMDR is taught in a two-part basic training followed by consultation hours, and full certification through EMDRIA in the United States, or the equivalent national association elsewhere, requires substantially more supervised experience than the basic training alone.
Ask whether they are certified rather than simply trained. Ask how many clients with your kind of history they have worked with. Ask how they handle stabilization, and listen for whether they treat it as a serious phase or a formality. Ask what happens if you become overwhelmed mid-session, because the answer will tell you a great deal about how carefully they work.
If your history involves childhood abuse specifically, learning how to choose a trauma-informed therapist can help you screen for the additional skills complex trauma treatment requires. If you are not yet steady enough to approach a memory directly, somatic exercises for nervous-system regulation may be a sensible place to begin rather than a delay.
A reasonable expectation
EMDR is a well-supported, well-structured treatment for post traumatic stress that helps a substantial proportion of the people who try it, that has a disputed mechanism and an uncontested outcome record for single incident trauma, and that requires more care and more time when the trauma began in childhood.
That is a genuinely good thing to be able to say about any psychological treatment. It is also considerably less than the transformation sometimes promised online, and knowing the difference in advance is part of what makes the treatment work.
Frequently Asked Questions
What is EMDR therapy for post-traumatic stress?
EMDR stands for Eye Movement Desensitization and Reprocessing. It is a structured trauma treatment that helps the brain process distressing memories so they feel less immediate, emotionally intense, and disruptive.
How does EMDR therapy work?
During EMDR, a person briefly focuses on a traumatic memory while participating in bilateral stimulation, such as guided eye movements, alternating taps, or tones. This process may help reduce the memory’s emotional intensity and allow it to be stored as something that happened in the past.
What are the eight phases of EMDR therapy?
The eight phases are history taking, preparation, assessment, desensitization, installation, body scan, closure, and reevaluation. Preparation and stabilization may require additional time for people with complex trauma or histories of childhood abuse.
Is EMDR effective for post traumatic stress disorder?
Research shows that EMDR can significantly reduce PTSD symptoms, particularly when the trauma involves a specific event. Its effectiveness is generally considered comparable to trauma-focused cognitive behavioral therapy, although individual results and treatment timelines vary.
Can EMDR be used to treat complex trauma?
EMDR may help people with complex trauma, but treatment often requires more preparation, careful pacing, and a longer timeline. A qualified therapist may use a phase-based approach to help the person develop emotional regulation and grounding skills before processing traumatic memories.
Does EMDR erase traumatic memories?
EMDR does not erase memories or make people forget what happened. It aims to reduce the emotional and physical distress connected to a memory so the person can remember the experience without feeling as though it is happening again.