The Flash Technique: What Early Research Shows

Research on the Flash Technique is real but early. A 2024 study of 654 people found disturbance dropped by more than two-thirds in about 15 minutes, and a small trial found it worked as well as abbreviated EMDR at easing a memory’s charge. No trial has yet pitted it against another active PTSD treatment, and its mechanism is still debated.

Search for this topic and most pages list every published study as a straightforward win, several maintained by the technique’s own developers. That’s worth knowing going in. The actual research is more interesting than that, and more mixed, once you look at what each study did and didn’t test.

What is the Flash Technique, in research terms?

The Flash Technique (FT) is a brief technique developed within EMDR. You hold something completely positive in mind while a facilitator periodically cues you to blink rapidly, and a disturbing memory stays at the edge of awareness the whole time, never described or examined directly. Clinical psychologist Philip Manfield introduced it in a 2017 case series describing four clients whose distress eased quickly.

Manfield designed FT as an optional tool for Phase 2 preparation, EMDR’s stabilization stage, not a replacement for full reprocessing. That detail matters for reading the research below: most studies measure a drop in SUDS, the 0-to-10 distress rating, not a cured diagnosis.

How much research actually backs it up?

Not a lot yet, and saying so plainly is more useful than padding it out. As of 2026, the evidence base is one published case series, one large uncontrolled multi-site trial, one small controlled lab comparison against EMDR, two randomized trials against an active comparator, two competing theoretical models, one related dual-task study on the mechanism, and one head-to-head randomized trial still running.

Two of those pieces, the original case series and the largest pooled trial, come from the technique’s own developer, Philip Manfield. The rest come from separate, independent research teams. Even so, no single finding here has been replicated by a second team yet. That’s normal for a technique this new, but worth knowing going in. Here’s what each piece actually found.

What did the largest study find?

The biggest single data point is a 2024 paper in Frontiers in Psychiatry by Manfield, Taylor, Dornbush, Engel, and Greenwald. It pooled four studies, two run during FT training workshops in the United States, one in Australia, one in Uganda, for a combined 654 people across 813 FT sessions.

Using a pre-, post-, and follow-up design, disturbance dropped by more than two-thirds after roughly 15 minutes of FT. No adverse effects were reported, and the gains held at follow-up. That’s a genuinely large, multi-site sample for a technique this new.

Here’s the honest caveat: none of the four sub-studies had a control group. At least two ran during FT trainings, so participants were often clinicians practicing on each other, not people who’d sought out treatment. A result this size, without a comparison arm, tells you FT is well tolerated and shows a real pre-to-post effect. It doesn’t yet tell you how that effect compares to simply resting, talking, or trying another brief technique.

Does it work as well as standard EMDR?

The closest direct test is smaller and more tightly controlled. A 2021 study in Frontiers in Psychology by Brouwers, de Jongh, and Matthijssen put 60 non-clinical adults through both FT and an abbreviated EMDR protocol, each targeting a real but everyday aversive memory.

Bayesian analysis found no meaningful difference between the two: both reduced the memory’s emotional charge and vividness by similar amounts. Participants rated FT as the more pleasant one to go through, likely because it never asks you to look straight at the hard material.

Worth flagging: this sample wasn’t clinical, wasn’t diagnosed with PTSD, and used a single memory in a single lab session. It’s a reasonable answer to “does FT do something real.” It isn’t yet an answer to “does FT treat PTSD as well as full EMDR.”

Is there a randomized trial with an actual comparison group?

Yes, and it’s the strongest clinical evidence FT currently has. A 2022 randomized-controlled trial by Yaşar and colleagues gave traffic-accident survivors either FT or the World Health Organization’s mhGAP stress-management module, an active, legitimate comparison rather than a plain waitlist.

The FT group showed significantly larger improvements in anxiety, intrusive memories, avoidance, overall traumatic stress, and quality of life. Those gains held for at least a month afterward.

A 2025 randomized trial in Current Psychology tested a similar idea in a different population: an internet-delivered FT protocol, three sessions over three days, against seven weeks of internet-delivered CBT, in breast cancer patients. Both eased traumatic stress, anxiety, and depression by similar amounts. That’s a useful data point, not proof the two approaches are interchangeable. One trial finding “no significant difference” is weaker evidence of equivalence than most headlines make it sound.

Why might the Flash Technique work, and is that settled?

Not entirely. Two explanations currently compete. A 2021 model by Sik-Lam Wong grounds FT in working-memory and neuroscience research, proposing that each blink briefly disconnects the memory from its fear response, gradually loosening its grip with repetition. That draws on the same working-memory research covered in our deeper piece on working memory theory, applied here to FT’s specific blink-based design.

A 2024 paper in the same journal by Perez-Strumolo argues something else is doing the work: Fredrickson’s broaden-and-build theory, where sustained positive emotion itself widens attention and coping resources, separate from any memory-taxing effect.

A closely related 2025 experiment sharpens the open question. It didn’t test FT by name, but it tested the design choice behind it: does covertly cueing the specific target memory during a dual-task exercise add anything? A 2025 study in the European Journal of Psychotraumatology by de Cort, Schruers, and Matthijssen ran 136 people through a trauma-film memory and a working-memory task, with or without a visual cue reactivating that memory. The cue added nothing measurable. A generic working-memory task alone worked just as well.

That’s not a strike against FT’s results. It is a real, unresolved question about why they happen.

What’s the trial to watch?

The ENHANCE trial, a protocol published in 2023 by Matthijssen and colleagues, is the one to track. It randomly assigns 130 people diagnosed with (complex) PTSD to six sessions of standard EMDR, EMDR 2.0, or the Flash Technique, tracking PTSD diagnosis and symptom severity as its main outcomes.

Recruitment began in October 2022 and was expected to wrap up around 2025. As of this writing, results aren’t published yet. This will be the first randomized trial to test FT directly against full EMDR in people formally diagnosed with PTSD, rather than a lab analog or a single-memory comparison, which is exactly the gap the studies above leave open.

Flash Technique research at a glance

Study	Design	Who was studied	What it found
Manfield et al., 2017	Case series (4 clients)	Clinical clients	Early illustrative reports, not a trial
Brouwers et al., 2021	Controlled lab study, N=60	Non-clinical adults	FT ≈ abbreviated EMDR; FT rated more pleasant
Yaşar et al., 2022	RCT vs. active comparator	Traffic-accident survivors	FT beat WHO’s mhGAP module; gains held 1+ month
Manfield et al., 2024	Open, uncontrolled, 4 sites, N=654	Mostly FT-training participants	Disturbance down 2/3+ in ~15 min; no adverse events
Breast cancer RCT, 2025	RCT vs. active comparator	Breast cancer patients	FT-based protocol ≈ 7-week iCBT
de Cort et al., 2025	Lab dual-task experiment, N=136	Non-clinical adults	Memory-specific cueing added nothing over generic dual-tasking
ENHANCE trial	RCT, N=130, results pending	Diagnosed (complex) PTSD	The head-to-head test still to come

Can you try the Flash Technique on your own?

Not really, and the research above explains why. In every study, a trained facilitator chose the target memory, tracked the person’s distress, and called out each “flash.” That’s not incidental; it’s how the technique is built. You can’t easily replicate a facilitator watching your response in real time and adjusting on the spot. See our answer to can you do EMDR on yourself? for more on that general limit.

If what you actually want is a way to work with everyday stress on your own time, that’s a different, appropriately scoped practice. EmEase, a self-guided EMDR app, offers visual and audio bilateral stimulation you can pace yourself, at app.emease.com, built for everyday tension and looping thoughts rather than clinician-cued trauma work. Our fuller look at self-administered EMDR research covers what’s known, and not known, about practicing bilateral stimulation without a clinician in the room more broadly.

What the research doesn’t yet settle

A few limits are worth naming together. Every controlled study so far is small. The largest study, at 654 people, has no control group, and the largest study with a control group, the traffic-accident trial, is a single trial run by one team. None of these findings has been replicated by a second research team yet.

No completed trial has yet compared FT against a full, standard course of EMDR in people diagnosed with PTSD, though ENHANCE should change that. And the two leading accounts of why FT works, blink-triggered fear-response disconnection and positive-emotion broadening, haven’t been reconciled with each other.

The bottom line

The Flash Technique has more research behind it than most brief clinical techniques get in their first decade, and what exists is genuinely encouraging: a large pre-to-post drop in distress, a randomized trial beating an active comparator, and rough parity with EMDR in the one direct lab test. It hasn’t yet cleared the higher bar of a completed, independent, head-to-head trial against standard treatment in diagnosed PTSD. Treat it as promising and still early, which is roughly where its own researchers place it too.