What Is EMDR and How Does It Work?

Eye Movement Desensitization and Reprocessing, better known by its acronym EMDR, is a form of psychotherapy developed in the late 1980s to reduce the distress tied to traumatic memories. While EMDR first gained recognition as a treatment for post-traumatic stress disorder (PTSD), researchers have since studied it for a broader range of mental health concerns.

What does EMDR therapy do?

During EMDR, a person briefly focuses on a distressing memory while following a back-and-forth stimulus, usually the therapist's moving finger or light bar, and sometimes taps and/or tones. This "bilateral stimulation" is thought to tax working memory during recall, which appears to reduce how vivid and emotionally charged the memory feels over time.

The guiding theory (the "adaptive information processing" model) holds that overwhelming experiences can be stored in an unprocessed form, leaving them a lasting source of distress. EMDR aims to help the brain reprocess and integrate these memories so they lose their emotional intensity.

Is EMDR therapy good for PTSD?

Yes. PTSD is where the evidence for EMDR is strongest. More than 30 randomized controlled trials support its use, and most international clinical practice guidelines, along with the World Health Organization, recommend EMDR as a first-line treatment for PTSD.

EMDR was developed by psychologist Francine Shapiro, who noticed while walking in a park that side-to-side eye movements seemed to lessen the intensity of her own distressing thoughts. Unlike therapies that work mainly by changing thoughts and behaviors, EMDR focuses on the distressing memory itself and how it is stored.

Some well-known figures have spoken publicly about EMDR. For example, Miley Cyrus has described it helping with stage fright, and Prince Harry has credited it with helping him cope with anxiety and grief. These accounts can raise awareness, but individual results vary widely.

How many EMDR sessions are needed for PTSD?

EMDR is usually delivered one-on-one, typically once weekly, over roughly four to 12 sessions, though some people need fewer and others more. Session length is often 60 minutes. Some protocols use twice-weekly sessions to shorten the overall timeline. The right number depends on the complexity of the trauma and individual response.

What to expect after an EMDR session

Many people feel tired or emotionally tender after a session, and processing can continue between appointments. Gentle, calming activities afterward can help. Therapists often suggest using the grounding and relaxation techniques taught early in treatment, and bringing any strong reactions back to the next session. There is no strict list of forbidden activities, but easing back into the day rather than jumping into something highly stressful is a reasonable approach.

Are there side effects?

EMDR is generally considered safe, and serious adverse events are rare in trials. That said, side effects are not always systematically tracked in research, so the full picture is still being studied. Reported effects are usually mild and temporary and can include:

A short-term increase in distress or emotional reactivity, sometimes between sessions
Vivid dreams or, occasionally, nightmares
Fatigue after a session

A temporary flare in symptoms during trauma-focused work is common and is not a sign that treatment is failing — it can be part of the process and should be discussed with the therapist.

A note on "the body releasing trauma"

You may see claims online that specific physical signs — trembling, waves of heat or chills, spontaneous yawning, or bouts of crying — mean the body is "releasing" trauma. These ideas come largely from body-based approaches such as Somatic Experiencing and are not established features of how EMDR works. People do sometimes notice physical sensations and emotional releases during trauma therapy, but there is no validated checklist of "trauma release" signs, and their presence or absence does not measure progress.

How to tell if EMDR is working

Progress usually shows up as distressing memories feeling less intense and less intrusive, less hypervigilance, and steadier mood and emotional regulation over time. For straightforward trauma, some people improve within a handful of sessions; more complex or repeated trauma often takes longer. Many clinicians find EMDR can work relatively quickly, but timelines are individual.

Who may not be a good candidate for EMDR?

EMDR is not right for everyone or every moment. People in an unsafe situation (such as ongoing abuse) generally need safety and stabilization first. Historically, conditions such as active psychosis, severe dissociation, or uncontrolled substance use were treated as reasons to avoid trauma-focused therapy, out of concern that intense processing could be destabilizing.

Importantly, the evidence here is evolving: Recent trials suggest EMDR can be delivered safely and effectively even in people with psychotic disorders when done by trained clinicians, though a temporary rise in symptoms can occur. The bottom line is that suitability and timing should be decided together with a qualified mental health professional who can tailor the approach to the individual.

Recap: the key points

What it is: EMDR is a structured psychotherapy in which a person briefly focuses on a distressing memory while following a back-and-forth stimulus, with the goal of reducing how vivid and emotionally charged that memory feels.
Where it works best: PTSD has the strongest evidence — over 30 randomized trials and first-line status in most international guidelines and the WHO.
Beyond PTSD: Research into depression, anxiety, OCD, chronic pain, and addiction is promising but still preliminary.
What treatment looks like: One-on-one, often once weekly, over roughly 4 to 12 sessions depending on the complexity of the trauma.
Safety and side effects: Generally safe, with mostly mild, temporary effects such as fatigue, vivid dreams, or a short-lived increase in distress. A brief flare in symptoms can be part of the process.
A caution on "releasing trauma": Specific physical "trauma release" signs are not an established part of how EMDR works and don't measure progress.
Who should be cautious: People in unsafe situations usually need stabilization first; suitability and timing are best decided with a qualified clinician.