Mechanism of EMDR- How it works

Curious about how EMDR actually works? 🎙️ Our latest podcast episode dives into the debate and science behind this powerful therapeutic approach. Discover why it's so much more than just eye movements and how it helps people worldwide. Join me, Tim Vermilion, on EMDR News Podcast as I unpack the real story. Listen now! #EMDR #MentalHealth #Therapy #Podcast

00:00 Welcome and Big Question
00:47 What People Think EMDR Is
01:37 Protocol Not Just Eyes
02:17 Working Memory Explained
03:42 Two Myths Debunked
05:02 Memory Feelings vs Facts
05:59 Body and Orienting Response
06:54 Memory Updating Theories
07:44 Brain Scans Reality Check
08:33 AIP Model for Clinicians
09:20 Putting It All Together
10:22 Dinner Party Summary
10:59 Disclaimer and Wrap Up

Transcript

Doc V 0:00

All right. Welcome back to the EMDR News Podcast. I'm Tim Vermilion, clinician-focused, research-informed, signal over noise. That's the whole deal here. If you haven't already liked and followed, please do. I'll wait Today I want to take on a question I get all the time from clients, from clinicians, from my own family and friends, honestly. How does EMDR actually work? And I'll be straight with you up front. The satisfying answer and the true answer are not the same answer. So if you came for the eye movements heal the trauma, the end, I'm gonna disappoint you a little. Stick with me anyway. The real story's better. So let's start with what everybody pictures. You think of EMDR, you think of the therapist's hand going back and forth, or the little tones, or those buzzers people hold, one in each hand. The bilateral stimulation, that's the part you can see, so naturally people assume that's the mechanism. Here's the thing, that's part of it. It is not the whole thing. And the honest headline is the mechanism is still debated. We're still arguing about exactly how it works. Now, before anybody panics and clicks away, we're debating the mechanism is not the same as it doesn't work. I want to nail that down early. EMDR is a researched, guideline-supported treatment for PTSD that has been shown to work with other populations and clinical presentations. The debate is about how, not whether. Hold onto that because I'm gonna come back to it. Okay, so why isn't it just the eye movements? Because EMDR isn't a trick with the eyes. It's a whole structured therapy. Eight phases. You take a history, you prep the person, you pick a target memory, you light that memory up, you do the sets of stimulation, you install a healthier belief, body scan, closure, and then you circle back the next session and check your work. So when somebody asks, "How does it work?" You've actually got to split the question. The eye movements are one ingredient. The full protocol is the whole meal. Those are not the same thing, and a lot of confusion comes from mushing them together. So what can I tell you with a straight face? The strongest evidence at the component level points to working memory and dual attention, and that sounds technical, so let me just say it like a human. Your working memory is limited. You cannot hold everything in your head at full volume at the same time. Nobody can. So picture this. You pull up a distressing memory, and at the same time, you're doing something demanding, following a moving target, say. Now, those two things are fighting over the same little patch of mental real estate. And what happens in study after study is when people recall an emotional memory while they're doing that taxing task, afterward, they rate it lower, less vivid, less intense, sometimes a little harder to grab, a little less detailed, fewer of those intrusive image qualities. So the memory changes, but careful, the experience of it changes. That's the word I want you to hang on to: experience. It feels less sharp, less overwhelming, less charged. Let me slow all the way down. What does that not mean? It does not mean the memory got erased. It does not mean it got more accurate, and it definitely does not mean we just explained full PTSD recovery in one neat sentence. All it means is one well-supported piece seems to turn down the vividness and the intensity under the conditions people have actually studied. That's a real result. I just refuse to inflate it past its size. Okay, let me knock down the two explanations you've probably heard because both of them go too far in opposite directions. Number one, the famous both sides of the brain story. The eye movements supposedly sync up your two hemispheres. It's so tidy. It's so satisfying. It would make such a good infographic, and it's usually way too confident. There's real research on eye movements and memory, but using hemisphere synchronization as your public explanation, the evidence doesn't carry that. So if that's the version you've been telling people, I've been there too. Time to retire it. Number two cuts the other direction. This is the idea that the bilateral stimulation is the magic ingredient, and everything else in EMDR is just decoration. That one also overreaches. Yeah, some studies show eye movements beating certain control tasks, but other studies, a totally different demanding task does about the same thing. And some of the clinical comparisons muddy whether the eye movements add anything extra beyond just retrieving the memory and being in good treatment. So here's how I'd actually say it precisely. Eye movements can be one effective dual attention task while the memory's switched on. They may matter, but they're not the whole therapy, and they are not a proven single mechanism. One ingredient, not the secret sauce. Now, there's a boundary here I will plant a flag on every single time: memory experience versus memory accuracy. If a treatment changes how vivid or how emotional a memory feels, that tells you exactly nothing about whether the memory is true, and it doesn't make freshly surfaced memory material accurate either. The research literature actually carries real cautions about this. Memory quality, false memory, especially in legal situations, recovered memory situations. And I want to thread this carefully because it cuts both ways. It is not EMDR plants false memories. It doesn't routinely do that. That's a scare story, and it's wrong. The sober version is just this. EMDR may change how a painful memory feels. It is not a tool for proving what happened and being honest about that, that's a trust thing. I can explain the mechanism without promising anybody certainty about their own past. All right. Second lane. This one's the body. A whole stack of studies pick up changes in arousal during and after EMDR. Heart rate, skin conductance, heart rate variability, breathing, EEG, all the autonomic stuff your nervous system does without asking you. And one way people frame it is the orienting response. Something novel, something rhythmic grabs your attention, keeps you anchored right here in the present while you're also touching that old memory. So your system kind of clocks it. You're remembering this. You're not reliving it And leash on again. Those arousal changes might be helping the processing, or they might just be reflecting it, or they might show up after the processing already started. We don't fully know. So the careful version is arousal regulation and orienting may contribute. May, love that word. Use it a lot. Third frame, and this one I genuinely like, memory updating. So during EMDR, the old memory's lit up, but new information can get in at the same time. You're safe now. You're allowed a different belief about yourself. You've got your adult brain online, and you keep getting that signal. This is a memory, not the thing happening again. So you're not just hitting replay. You're pulling the memory up inside a room where new associations can actually stick to it. The lab words for that are extinction and reconsolidation, theories about how old emotional learning can get rewritten when you reactivate a memory and feed in new info. Great bridges to the wider memory science, but bridges, not the destination. I'm not going to stand here and tell you EMDR has been proven to run on reconsolidation. The honest line is that kind of updating is a plausible contributor. And then the brain scans. Oh, people love the brain scans. Nothing makes a claim feel more official than a colorful brain with a glowing spot on it. I get it. They're persuasive. Here's the truth. The scans add biological plausibility. They do not settle the question. Across the imaging, MRI, fMRI, SPECT, EEG, researchers have reported changes in prefrontal, limbic, hippocampal, thalamic activity around EMDR. But a lot of those studies are small or single cases or uncontrolled or built to spot a correlation, not to prove a cause. So the good version is preliminary brain correlates have been reported. The version I won't say is brain scans prove how EMDR works. That's a canyon between those two, and I'm not jumping it. Now let me bring in AIP, because if you're a clinician, you've been waiting for it. The adaptive information processing model. That's EMDR's main clinical framework. Core idea, symptoms can be tied to memories that never got fully processed at the time. They're kind of stuck in there raw, and EMDR is trying to link them up with more adaptive information so they quit firing off the same distress in your present-day life. And I lean on AIP all the time because it's how clinicians actually think. Case formulation, treatment planning, making sense of why some thirty-year-old memory is still emotionally live. But I'll put the same boundary on it. AIP is the clinical model. It's how we organize the work. It is not a finished map of the brain. Useful framework, not proven mechanism. Both things are true. So Where does all this leave us? If you want my honest best answer, it's plural. It's a few things working together. You activate the memory, you tax attention and working memory. You're regulating arousal. You're keeping the person in the present. New associations form, the emotional meaning shifts, and the whole thing's happening inside a structured protocol with a real clinician in a real relationship. if you want the one strong pillar, it's that working memory dual attention effect on vividness and emotion. The arousal piece, the orienting, the extinction and reconsolidation stuff, those sit in the plausible contributor column. AIP's the clinical model. The brain imaging is early, and not one of those gets to stand up and claim it's the whole story. I know. It's several interacting processes inside a structured therapy is never going to outmarket the eye movements heal the trauma. It won't fit on a mug, but it's a lot more accurate, and accurate is the brand here. So let me leave you with the version you can actually repeat at a dinner party without me wincing. The mechanism's still debated, but the strongest evidence says that recalling something distressing while your attention is also tied up by eye movements or another demanding task can take the edge off how vivid and how intense that memory feels. And a few other things, the arousal regulation, the orienting, the memory updating, the structure of the therapy itself, they probably pitch in too. That keeps the center without overclaiming it, and that's about as honest as the science currently lets us be. Quick reminder before I let you go, this is educational. It is not therapy, it's not supervision, it's not emergency care, and it's no substitute for talking to your own provider. The full article with all the VA, PubMed, and EMDRIA sources is in the show notes if you want to go check my work. Please do, actually. That's it for this one. Thanks for spending the time with me. I'll catch you on the next one. Take care.