EMDR (Eye Movement Desensitization and Reprocessing) is a structured therapy where you recall distressing memories while following a form of side-to-side stimulation, typically guided eye movements. This combination helps your brain reprocess traumatic memories so they lose their emotional charge. A typical course runs about six to nine weekly sessions, each lasting 50 to 60 minutes, and the therapy follows eight distinct phases from start to finish.
The Core Idea Behind EMDR
EMDR rests on a theory called Adaptive Information Processing. The basic premise: when something traumatic happens, your brain sometimes stores the memory in a raw, unprocessed form. That stored memory keeps its original intensity, so a sound, image, or thought can trigger the same fear, helplessness, or panic you felt during the event itself. The memory is essentially “stuck.”
Bilateral stimulation, the back-and-forth element of EMDR, appears to unlock this stuck processing. Brain imaging research shows that alternating stimulation activates memory-related areas in the temporal lobes while simultaneously quieting the parts of the prefrontal cortex responsible for emotion regulation and self-monitoring. In practical terms, this seems to put the brain in a relaxed, open state where it can revisit a painful memory without the usual defensive reactions. The memory gets filed away properly, connected to more adaptive beliefs about yourself, and stripped of its original distress.
The Eight Phases of Treatment
Phase 1: History and Planning
Your therapist takes a detailed history to understand your symptoms, triggers, and the events driving them. Together, you identify specific memories to target and decide on a treatment sequence. The memories considered most foundational to your current problems are typically prioritized first. This phase may also involve a technique called “floatback,” where you trace a current emotional reaction backward to its earliest memory origin.
Phase 2: Preparation
Before any memory processing begins, your therapist explains exactly what EMDR involves, answers your questions, and teaches you specific coping techniques for managing emotional distress. These self-regulation tools matter because processing can temporarily bring up strong feelings, and you need reliable ways to stabilize yourself both during and between sessions. This phase also builds the therapeutic relationship so you feel safe enough to engage with difficult material.
Phase 3: Assessment
You and your therapist activate the target memory by identifying its key components: the most vivid image associated with it, the negative belief it created about you (something like “I’m not safe” or “It was my fault”), and the positive belief you’d rather hold instead. You rate how true the positive belief feels on a 1-to-7 scale and how disturbing the memory feels on a 0-to-10 scale. You also note where you feel the distress physically in your body. These ratings create a baseline to track progress.
Phase 4: Desensitization
This is the active processing phase and the heart of EMDR. You hold the target memory in mind, including its image, negative belief, and physical sensations, while following bilateral stimulation. The most common form is watching your therapist’s finger move back and forth, but therapists also use alternating tones through headphones or handheld vibrating devices that pulse left-right.
After each set of eye movements (usually lasting 20 to 30 seconds), your therapist asks you to take a deep breath, let go of the material, and report whatever came up: new images, thoughts, emotions, or body sensations. Based on your response, the therapist guides your next focus of attention and may adjust the speed, length, or type of stimulation. You’re instructed to stay open to whatever arises without trying to control it. Processing continues until the memory’s disturbance rating drops to zero or as low as it can go.
Phase 5: Installation
Once the distress from the memory has cleared, the therapist pairs the memory with your chosen positive belief. You hold both together during another set of bilateral stimulation, strengthening the new association until the positive belief feels fully true (a 7 on the 1-to-7 scale). The goal is that when the memory comes to mind afterward, it connects to the healthier belief rather than the old one.
Phase 6: Body Scan
You think about the original memory along with the new positive belief and scan your body for any remaining tension, tightness, or unusual sensation. If anything surfaces, the therapist targets it with additional sets of bilateral stimulation until the physical residue clears. Trauma often lives in the body as much as the mind, so this step ensures the reprocessing is thorough.
Phase 7: Closure
If the memory hasn’t been fully processed by the end of a session, the therapist uses the self-control techniques from the preparation phase to bring you back to a stable, calm state. You’ll be told what to expect between sessions (sometimes new memories, dreams, or emotions surface as processing continues on its own) and may be asked to keep a brief log of any disturbances that come up, which can become targets in future sessions.
Phase 8: Reevaluation
At the start of each new session, the therapist checks in on previously processed memories to confirm the treatment effects held. If distress has returned or new related material has emerged, those become the next focus. This phase ensures nothing falls through the cracks.
What a Session Actually Feels Like
People often describe EMDR as surprisingly different from talk therapy. You don’t need to narrate your trauma in detail or analyze it extensively. Instead, much of the processing happens internally while you follow the bilateral stimulation. Some people experience the memory shifting rapidly: the image may become less vivid, emotions may change from fear to sadness to calm, or entirely new associations may surface.
Sessions can be emotionally intense, especially early on. It’s normal to feel a temporary spike in distress as a memory is activated before it begins to resolve. Some people feel tired or emotionally raw after a session. Between sessions, you might notice vivid dreams, new memories surfacing, or shifts in how you react to old triggers. These are generally signs that processing is continuing.
How Effective EMDR Tends to Be
The results for PTSD are strong. In a study at Kaiser Permanente, 100% of people with a single traumatic event and 77% of those with multiple traumas no longer met the criteria for PTSD after an average of six 50-minute sessions. Other randomized controlled trials found that 84% to 90% of single-trauma survivors lost their PTSD diagnosis after just three 90-minute sessions. In a head-to-head comparison with a commonly prescribed antidepressant, 91% of the EMDR group no longer had PTSD at follow-up, compared with 72% in the medication group.
These numbers are for PTSD specifically, which is where EMDR has the deepest evidence base. The therapy is increasingly used for anxiety, phobias, grief, and other conditions, though the research for those applications is still developing.
Why You Shouldn’t Try It Alone
Videos and apps offering DIY EMDR are easy to find online, but self-administering the memory-processing phases carries real risk. Francine Shapiro, who developed EMDR, warned that processing can cause a short-term surge in distress that occasionally includes a temporary increase in suicidal thoughts, particularly when dissociated memories, emotions, or physical sensations resurface unexpectedly. She stated directly that inadequate screening, preparation, or implementation “can have literally fatal consequences.”
The preparation phases exist for a reason. A trained therapist evaluates whether you’re ready for processing, ensures you can use self-regulation techniques effectively, and monitors your response in real time to adjust the approach. Even in research trials testing internet-delivered EMDR, participants had weekly contact with a clinical psychologist and were never fully unsupervised. The calming exercises from Phase 2 are generally safe to practice on your own, but the active memory reprocessing phases are not designed for solo use.
Types of Bilateral Stimulation
While the classic image of EMDR involves following a therapist’s finger with your eyes, that’s only one option. Therapists also use auditory tones that alternate between left and right ears through headphones, or small handheld devices that vibrate in an alternating pattern. All three types produce similar effects in the brain: increased activity in memory-processing regions and decreased activity in areas tied to emotional reactivity and self-monitoring. Your therapist may try different forms to find what works best for you, and some people find tactile or auditory stimulation more comfortable than sustained eye movements.