EMDR — Eye Movement Desensitization and Reprocessing — is a structured psychotherapy approach used to help people recover from trauma and distressing life experiences. Developed by psychologist Francine Shapiro in the late 1980s, it’s now among the most studied trauma treatments in the field, with endorsements from the APA, WHO, and VA/DoD clinical guidelines.
The bilateral stimulation component — typically guided eye movements, though audio tones and tactile taps are also used — seems unusual before you understand what it’s doing. This page explains the mechanism, walks through the eight-phase protocol, and describes what sessions actually look like from a patient’s perspective.
What EMDR Is Actually Doing
The theoretical foundation is called Adaptive Information Processing. The core idea: traumatic memories sometimes get stored in an unprocessed form — preserved with their original sensory details, emotions, and body sensations intact, as if the nervous system never properly filed them. When something in the present triggers that memory, it activates not as a neutral recollection but with much of its original emotional charge.
EMDR uses bilateral stimulation while a person holds the traumatic material in mind. The current model suggests it activates the brain’s natural information-processing system — similar in some ways to what happens during REM sleep, when memories are consolidated and integrated. The distress associated with the target memory typically decreases over processing, and the negative beliefs attached to it tend to shift.
The 8 Phases of EMDR Therapy
EMDR follows a structured eight-phase protocol. These aren’t eight sessions — some phases span multiple meetings, some occur within a single one. The timeline depends on the complexity of what’s being processed and how the person responds.
Phase 1 — History-taking and treatment planning. The therapist builds a comprehensive picture of current symptoms, relevant history, and which memories will be targeted. For complex presentations this can take several meetings.
Phase 2 — Preparation. Before any processing begins, the therapist works to build distress tolerance — grounding techniques, stabilization resources, a therapeutic relationship that feels safe. Processing doesn’t start until someone has adequate stability in place.
Phase 3 — Assessment. A specific target memory is identified. The therapist helps the person identify the image representing the worst part of the memory, the negative belief they hold about themselves in connection to it, the positive belief they’d prefer to hold, and how distressing it currently feels on a 0–10 scale.
Phase 4 — Desensitization. The bilateral stimulation phase. The person holds the target memory in mind while the therapist guides the eye movements. After each set, the person reports what came up — an image, a thought, a body sensation. The therapist follows the material wherever the processing naturally leads. Distress levels are monitored throughout.
Phase 5 — Installation. Once distress around the target has reduced, the therapist works to strengthen the positive belief the person identified, also using bilateral stimulation.
Phase 6 — Body scan. The person holds both the target memory and the positive belief in mind simultaneously and scans their body for residual tension. Processing continues until the body scan is clear.
Phase 7 — Closure. Every session ends with closure, regardless of where processing landed. Grounding techniques return the person to equilibrium. Incomplete processing across sessions is normal — the person always leaves in a stable state.
Phase 8 — Reevaluation. At the start of subsequent sessions, the therapist reviews what was processed. Has distress remained low? What new material has surfaced? This informs what gets targeted next.
What an EMDR Session Actually Looks Like
Processing sessions typically run 60 to 90 minutes. The therapist moves two fingers horizontally across the person’s visual field; the person tracks the movement. Some therapists use handheld tappers or alternating audio tones — the bilateral stimulation mechanism is the same. Sets run approximately 20 to 30 seconds, followed by: “What are you noticing?” The person reports whatever came up without editing it. The therapist responds briefly and begins the next set.
Sessions feel different from standard talk therapy — less narrative, more attention to what’s happening internally in real time. Some people experience intense emotion during processing; others describe a gradual shift without obvious release. The distress associated with a target memory often changes noticeably within a single session. Between-session processing continues — heightened emotions or vivid dreams in the days following are common, which is why the preparation phase matters.
What EMDR Is Used to Treat
PTSD is the primary indication with the strongest evidence base. EMDR is also used for specific phobias, panic disorder, complicated grief, and anxiety and depression with roots in adverse experiences. Research continues on additional applications.
For adults navigating PTSD or complex trauma in Massachusetts, understanding what evidence-based treatment options look like — including EMDR through qualified providers — is part of finding the right fit. Trauma and PTSD treatment at Waterside Behavioral Health uses structured, clinician-led approaches to help adults process and recover from traumatic experiences.
Is EMDR Evidence-Based?
Yes. The APA, WHO, VA, and DoD all include EMDR in their trauma treatment guidelines. The evidence is strongest for single-incident PTSD; research on complex presentations is ongoing. For a deeper look, see our post on whether EMDR is evidence-based.
How to Find a Qualified EMDR Therapist
EMDRIA — the EMDR International Association — maintains training and certification standards. An EMDRIA-certified therapist has completed an approved training program and a specific number of supervised hours. EMDR is a structured protocol implemented very differently by someone with proper training versus someone who attended a brief workshop. For more on what certification means and how to evaluate a provider, see our post on finding a qualified EMDR therapist.
Frequently Asked Questions
How many EMDR sessions does it take?
Highly variable. Single-incident trauma may respond in 6 to 12 sessions. Complex trauma with multiple targets typically takes considerably longer. The preparation phase alone can span several sessions before processing begins.
Is EMDR better than CBT for PTSD?
The research doesn’t support a clear winner. Both have strong evidence for PTSD. They work differently — CBT involves explicit discussion and restructuring of trauma-related thoughts; EMDR is less talk-based and more focused on bilateral-stimulation-assisted processing. Some people respond better to one than the other. A good clinician can help identify the better fit.
Can EMDR make things worse before they get better?
Sometimes. Processing disturbing material can temporarily increase distress between sessions — more vivid dreams, heightened emotions, new memories surfacing. This is exactly why the preparation phase exists. A well-trained therapist won’t begin processing until someone has adequate stabilization resources in place.
Understanding Your Options
EMDR is one tool in a broader set of evidence-based approaches for trauma. For adults in Massachusetts dealing with PTSD or complex trauma, finding the right treatment means understanding what’s available and what level of care fits what you’re navigating.
Our team at Waterside Behavioral Health in Plymouth, MA works with adults through structured, clinician-led trauma treatment. An evaluation is the starting point — it determines what approach and what level of care fits your situation.

