What Actually Happens in Your Brain When You Begin EMDR

Lianne Perry, MA, MSc., RCC

A quiet moment of orienting after waking.

Many people come into their first EMDR sessions curious, hopeful, and a little unsure.

They often ask some version of the same question.“What is actually happening in my brain when we do this?”

It is a fair question. EMDR can look simple from the outside, but a lot is going on under the surface.

Before anything changes, safety comes first

One of the most important things to understand about EMDR is that it does not start with diving into painful memories. It starts with your nervous system.

Before we ever process past experiences, we spend time building stability. We get to know how your body responds to stress. We practice grounding, containment, and ways to bring your system back to a sense of safety.

From a brain perspective, this matters because your nervous system needs to feel resourced enough to tolerate new information. If your system is constantly in survival mode, your brain will prioritize protection over processing.

This early phase is not a delay. It is what allows deeper work to happen safely later.

When EMDR begins, your brain does something different

When EMDR processing starts, we are not forcing your brain to relive the past. We are helping it do what it naturally knows how to do.

Under stress or trauma, certain memories can get stuck. They are stored with the original emotions, body sensations, and beliefs intact. This is why something small in the present can suddenly feel overwhelming, even if you logically know you are safe.

During EMDR, bilateral stimulation helps your brain shift how those memories are held. Instead of staying frozen in a threat based loop, your brain begins to link the past to the present.

In simple terms, your brain starts updating the file.

What clients often notice in session

Behind the scenes, this process can feel surprisingly subtle.

Some people notice images shifting, becoming more distant or less vivid. Others notice changes in body sensations, like tension easing or warmth spreading. Sometimes thoughts or insights appear that feel new or more balanced.

Often, clients say things like:“I know this happened, but it does not feel the same anymore.”Or“It feels like something has settled.”

This is your brain integrating information rather than reacting to it.

Why you do not have to talk everything through

One of the most misunderstood parts of EMDR is the idea that you must explain or describe everything in detail.

You do not.

Your brain does the work whether or not you have words for it. You can notice sensations, emotions, or shifts without needing a narrative. This is especially helpful for people whose experiences are fuzzy, fragmented, or difficult to put into language.

Healing does not require perfect memory. It requires your nervous system to complete what it could not finish at the time.

What is changing underneath

From a nervous system perspective, EMDR helps reduce the intensity of old threat responses. Your brain learns that the experience is over. Your body no longer needs to stay on high alert.

This is why people often notice changes outside of session. Triggers feel less intense. Reactions feel slower. Choices feel clearer.

The past does not disappear. It simply takes up less space.

Why the pace matters

One of the most important parts of EMDR is pacing.

Your brain integrates best when it is not overwhelmed. This is why sessions often move in waves, processing a little, then grounding again. We follow your nervous system rather than pushing through it.

Healing is not about forcing resolution. It is about allowing your system to reorganize at a pace it can handle.

What EMDR is really doing

At its core, EMDR helps your brain do something very human.

It helps you remember without re experiencing it. It helps your body recognize that you are safer now. It helps old experiences move from the present tense into the past.

For many people, this creates a sense of relief that feels hard to describe but very real.

Not dramatic. Not sudden. Just quieter inside.

Joey’s Take 🐾🐾

Was I asleep? Yes. Did I hear a suspicious noise? Also, yes. I investigated, realized I'm safe, and returned to my regular programming.

Sometimes I get startled by something unexpected. I shake it off, check my surroundings, and then move on.

Turns out, brains are not that different.

About Lianne

I’m Lianne Perry, a Registered Clinical Counsellor in BC who works online with clients across Canada. I specialize in trauma, anxiety, and life transitions, and I’m certified in EMDR, a powerful approach that helps people heal without having to relive every detail of the past. My sessions are grounded, collaborative, and often a mix of talk therapy and practical tools. When I’m not in session, you’ll probably find me hiking with my Aussie, Joey, or sitting by the ocean, my favourite co therapist.