Can Playing Tetris Ease Traumatic Flashbacks? What the New Lancet Psychiatry Trial Shows

By Dr. Lee Wen Pei, Psychiatrist · 8 October 2026

Short answer: possibly, for some people. In a randomised trial published in The Lancet Psychiatry in March 2026, healthcare workers who briefly recalled one traumatic image and then played Tetris for 20 minutes had about 70% fewer intrusive memories after four weeks than people who listened to music or had usual care.[1] The benefit lasted six months. But the reminder step is essential, the sample was narrow, and this is not a replacement for PTSD treatment.

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When a picture won’t leave your head

In my clinic, people rarely describe trauma as a story. They describe a picture.

The face of the other driver just before the crash. A patient’s eyes in the last minute of resuscitation. The colour of a room. These images come back without warning, while queuing at the bank or lying in bed at 2am. They feel as sharp as the day it happened.

Psychiatrists call these intrusive memories. Most people know them as flashbacks. They are the hallmark symptom of post-traumatic stress disorder (PTSD), but you don’t need a PTSD diagnosis to have them. Plenty of people carry a few stubborn images for months or years and never see anyone about it.

So when I saw a headline saying that playing Tetris, the old falling-blocks game, could reduce these flashbacks, I was sceptical. I went and read the full paper. This article is what I found.

What did the Tetris study do?

The trial is called GAINS-02. It was led by Professor Emily Holmes and colleagues and published in The Lancet Psychiatry in March 2026.[1]

They recruited 99 healthcare workers from the UK’s National Health Service. All had worked in hospitals that admitted COVID-19 patients and had been through at least one traumatic event at work. To join, each person had to report at least three intrusive memories in the week before screening.

Participants were split into three groups:

1. The Tetris group (40 people). One guided online session, then free to use the method on their own for six months.
2. A music group (39 people). The same guided session, but they listened to music for 20 minutes instead of playing Tetris.
3. Usual care (20 people). They carried on with whatever support they already had.

The music group matters. It means the researchers weren’t just comparing Tetris against “nothing”. Both groups got the same attention, the same platform and the same amount of contact. Neither group was told which one was the real treatment.

What happened in a Tetris session?

The guided session lasted about an hour over video call. It was run by trained research assistants, not therapists.

Participants wrote down their intrusive memories and picked one. They brought that image to mind for a few seconds. They did not describe the event or talk through what happened. Then they learned a technique called mental rotation and played Tetris for 20 minutes.[1]

After that, they could repeat the routine whenever they liked: recall one image briefly, rate how vivid it was, play 20 minutes of Tetris. On average, people used it about seven more times on their own.

What did they find?

Figures from Beckenstrom et al., Lancet Psychiatry 2026.[1]

By week four, the typical person in the Tetris group was down to less than one intrusive memory a week. In both the music group and the usual-care group, the typical number was still five.

The effect lasted. By six months, 28 of the 40 people in the Tetris group (70%) reported no intrusive memories at all.[1]

Other symptoms improved too. Overall PTSD symptom scores dropped more in the Tetris group, and in the first month anxiety, low mood, sleep and day-to-day functioning also got better.

One detail caught my eye as a clinician. A memory was more likely to stop intruding when the person scored higher at Tetris and when the recalled image was less vivid. In other words, the more fully the game occupied the mind, the better it seemed to work.

Why Tetris, of all things?

The idea comes from how memory works.

When we recall a memory, it doesn’t just play back like a video. For a short while after recall, the memory becomes soft and changeable, and then the brain stores it again. Researchers call this reconsolidation.[3]

Trauma flashbacks are mostly visual. They live in the part of the mind that handles mental pictures, sometimes called the mind’s eye. That space has limited capacity. It can only hold so much at once.

Tetris uses exactly that space. You have to picture shapes, turn them and fit them together. So if you briefly bring up the traumatic image and then play Tetris, the game competes with the image for room in the mind’s eye while the memory is being stored again. The memory gets saved back in a weaker, less vivid form. It is less likely to jump out at you later.

The important part: you don’t erase what happened. You still remember the event. What fades is the sharp, intrusive picture that keeps ambushing you.

What is mental rotation?

This is how the participants were taught to play.

Imagine holding an L-shaped puzzle piece. One way to fit it into a gap is to keep turning the real piece in your hand until it clicks. That’s trial and error.

The other way is to keep your hands still and picture the L-shape spinning in your head. “Turn it this way… no. This way… yes, that fits.” Only then do you put it down.

In Tetris, that means: when a block appears, turn it in your mind first, decide where it should go, then press the buttons to move it there. Participants still played the real game. Mental rotation was simply the way they were asked to play it, so the mind’s eye stayed busy the whole time instead of the thumbs doing the work.

Is the Tetris method like EMDR?

Partly. I practise EMDR (eye movement desensitisation and reprocessing), and the resemblance struck me straight away.

In EMDR, the client holds a disturbing image in mind while following the therapist’s hand with their eyes, or listening to alternating tones. One well-supported explanation is that this taxes working memory. The image has to compete for limited mental space, so it becomes less vivid and less upsetting, and it is stored again in that softer form.

That is very close to the Tetris idea. Both methods only need the memory to be briefly switched on. Neither requires you to tell the whole story. Both seem to work by making the image less vivid.

But the differences are real:

• Timing. In EMDR, the image and the eye movements happen at the same time. In the Tetris method, the brief recall comes first and the game follows.
• Depth. EMDR is a full therapy. It works with the beliefs attached to the trauma (“I am to blame”, “I am not safe”), the emotions, and the links to older memories. The Tetris method doesn’t touch any of that. It targets one picture at a time.
• Who does it. EMDR needs a trained therapist. The Tetris method was self-run after a single session with a non-clinician.

There is also an open question here. The Tetris researchers argue the task must be visual. Yet EMDR also works with sounds or taps instead of eye movements. That suggests something more than visual competition may be going on, at least in EMDR.

The way I see it, the Tetris method is a stripped-down cousin of one part of EMDR. It may help with the flashback itself. It isn’t designed to help with the meaning a trauma leaves behind.

What do earlier Tetris studies tell us?

This trial didn’t appear out of nowhere. Holmes’ group and others have studied the Tetris idea for over 15 years.[2] Reading through that work, a few lessons stand out.

The reminder is essential. In a 2015 study, Tetris almost eliminated flashbacks of a distressing film, but only when people saw a brief reminder of the film first. Tetris without the reminder did nothing. The reminder without Tetris did nothing either.[3] A 2019 German study also found Tetris with no reminder had no effect.[8]

Timing matters. Playing Tetris before a distressing event didn’t help. It needs to come after the memory has been briefly called up.[4]

It has worked in the real world. In a 2017 trial in an Oxford emergency department, people who had just been in a road accident got a reminder plus about 20 minutes of Tetris within six hours. They had fewer flashbacks in the following week.[5] A 2024 case series of 12 frontline NHS staff saw flashbacks drop by about 59%.[11]

It may not need to be Tetris. A 2025 study found a different, custom-built visual puzzle also reduced flashbacks.[12] That supports the idea that the kind of mental work matters more than the brand of game.

But “visual only” is less certain than it sounds. One 2017 study found a word game worked about as well as Tetris, possibly because it was harder.[6] How demanding the task is may matter as much as whether it is visual.

Not every study worked. A Dutch team testing a different game app found no effect.[7] A Norwegian replication with 149 students found no difference between groups.[9] An Australian study found that visual tasks reduced how often flashbacks happened, but not how distressing they were when they did come.[10]

I include the negative studies on purpose. A method that works in one trial and fails in another is worth taking seriously, but not worth overselling.

What are the limitations of the Tetris study?

I find this study genuinely encouraging. I also have reservations, and I think readers deserve to hear them.

Most participants weren’t diagnosed with PTSD. Nobody had a clinical interview. Everything was self-reported. About half scored in the probable-PTSD range on a questionnaire, and that group did improve, but this was an extra analysis after the fact. These were people with troublesome recurring memories, not necessarily the patients I see with established PTSD.

The trauma was mostly distant, and often ongoing. Two-thirds of participants were more than three months past their trauma. About half were still being exposed to traumatic events at work during the study. That’s realistic for healthcare workers, and the method still helped. But it is a specific group.

Complex trauma is a different problem. Many people carry trauma from childhood, from abuse, or from years of difficult relationships. Their suffering isn’t just a few vivid pictures. It’s shame, mistrust, a sense of being broken. A method aimed at one image at a time was never designed for that.

The sample was narrow. 86% were women and 90% were White.[1] We don’t yet know how this works in Malaysian or other Asian populations.

Commercial interests. Several authors work for the company that built the digital platform, and Professor Holmes founded a company around the method. That doesn’t make the results wrong. It does mean independent replication matters.

How to try the Tetris method safely

What follows is my reading of the research, not an official protocol. It isn’t a replacement for proper assessment or treatment.

The key point is simple. The visual task must come right after a brief reminder of the intrusive image. You don’t need to recall the whole incident. A few seconds of the picture is enough.

1. Pick one image. Choose one specific flashback picture, not the whole event.
2. Bring it to mind briefly. A few seconds. Don’t replay the story, analyse it, or push it away.
3. Play Tetris for about 20 minutes, soon after. Before each move, turn the block in your head first, decide where it goes, then press the buttons.
4. Keep a simple tally. Note how many times that image intrudes each day. Watch the trend over a few weeks.
5. Repeat as needed. One image per session. Target another image, or a new one, another day.

A practical idea I’ve been thinking about: when a flashback pops up on its own, the image is already “switched on”. That moment could be the cue to play. This hasn’t been tested as such, so treat it as something to try rather than something proven.

Other activities that might work

The research mainly supports Tetris. In theory, any task that keeps your mind’s eye busy with shapes and space could help: jigsaw puzzles, tangrams, a Rubik’s cube, building Lego from a diagram, drawing or copying shapes.

Things that probably won’t do the same job: scrolling social media, watching videos, podcasts, music, or chatting. They distract you, but they don’t occupy the mind’s eye in the same way. In the trial itself, music didn’t work.

When to see a professional instead

• If even a few seconds of the image is overwhelming.
• If you feel numb, spaced out, or “not really there” (dissociation).
• If the trauma goes back to childhood or was repeated over years.
• If shame, guilt, low mood or thoughts of self-harm are part of the picture.
• If the “brief reminder” keeps turning into long periods of going over the event.

In these situations, trauma-focused therapies such as EMDR or trauma-focused CBT remain the treatments with the strongest evidence. A visual task might still be a useful extra between sessions, but it shouldn’t carry the whole load.

Also keep your expectations realistic. The evidence says flashbacks tend to come less often. It doesn’t promise they’ll hurt less when they do come.[10]

What I hope future research will show

• Trials in people properly diagnosed with PTSD, using clinical interviews.
• Results in complex and childhood trauma.
• Studies in Malaysia and other Asian countries, and in more diverse samples overall.
• Whether using a spontaneous flashback as the cue works as well as deliberate recall.
• Whether the task truly needs to be visual, or simply demanding enough.
• Independent replication by teams with no commercial stake.
• Whether it adds anything when combined with EMDR or trauma-focused CBT.
• Whether it can reduce the pain of a flashback, not just how often it comes.

Frequently asked questions

Can playing Tetris really reduce traumatic flashbacks?

In the 2026 GAINS-02 trial, a brief image reminder followed by 20 minutes of Tetris cut intrusive memories by about 70% at week 4 compared with music or usual care, and the effect lasted to six months.[1] Tetris alone, without the reminder, has not worked in earlier studies.[3]

How does the Tetris method work?

A recalled memory is briefly changeable before it is stored again. Tetris competes with the traumatic image for space in the mind’s eye during that window, so the image is stored back less vividly and intrudes less often. You still remember the event.

Is the Tetris method the same as EMDR?

No. Both briefly activate a memory and seem to reduce its vividness, but EMDR is a full therapy with a trained therapist that also works on beliefs, emotions and linked memories. The Tetris method targets one image at a time.

Can Tetris replace PTSD treatment?

No. Most trial participants had no formal PTSD diagnosis, and the method hasn’t been tested in complex or childhood trauma. Trauma-focused therapies remain the best-supported treatments.

When should I see a professional instead?

If recalling the image is overwhelming, if you feel numb or spaced out, if the trauma is from childhood or repeated, if shame, low mood or self-harm thoughts are present, or if the brief reminder turns into long rumination.

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A final thought

What I like about this research is how humble the tool is. A game most of us played as children, used in a deliberate way, appears to loosen the grip of an image that has been haunting someone for months.

It won’t replace therapy. It won’t heal the deeper wounds trauma can leave. But for someone whose day keeps being interrupted by the same picture, it might be a small, practical thing to try. If the pictures keep coming, or there’s more underneath them, please reach out to a mental health professional.

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References

1. Beckenstrom AC, Bonsall MB, Markham A, et al. A digital imagery-competing task intervention for stopping intrusive memories in trauma-exposed health-care staff during the COVID-19 pandemic in the UK: a Bayesian adaptive randomised clinical trial. Lancet Psychiatry. 2026;13(3):233-247. doi:10.1016/S2215-0366(25)00397-9 · PMID 41720573
2. Holmes EA, et al. Key steps in developing a cognitive vaccine against traumatic flashbacks: visuospatial Tetris versus verbal Pub Quiz. PLoS One. 2010;5(11):e13706. doi:10.1371/journal.pone.0013706
3. James EL, et al. Computer game play reduces intrusive memories of experimental trauma via reconsolidation-update mechanisms. Psychol Sci. 2015;26(8):1201-15. doi:10.1177/0956797615583071
4. James EL, et al. Playing the computer game Tetris prior to viewing traumatic film material and subsequent intrusive memories: examining proactive interference. J Behav Ther Exp Psychiatry. 2016;53:25-33. doi:10.1016/j.jbtep.2015.11.004
5. Iyadurai L, et al. Preventing intrusive memories after trauma via a brief intervention involving Tetris computer game play in the emergency department: a proof-of-concept randomized controlled trial. Mol Psychiatry. 2018;23(3):674-682. doi:10.1038/mp.2017.23
6. Hagenaars MA, et al. Tetris and Word games lead to fewer intrusive memories when applied several days after analogue trauma. Eur J Psychotraumatol. 2017;8(sup1):1386959. doi:10.1080/20008198.2017.1386959
7. Asselbergs J, et al. Development and testing of TraumaGameplay: an iterative experimental approach using the trauma film paradigm. Eur J Psychotraumatol. 2018;9(1):1424447. doi:10.1080/20008198.2018.1424447
8. Brühl A, et al. Preventive efforts in the aftermath of analogue trauma: the effects of Tetris and exercise on intrusive images. J Behav Ther Exp Psychiatry. 2019;64:31-35. doi:10.1016/j.jbtep.2019.01.004
9. Brennen T, et al. Investigating the frequency of intrusive memories after 24 hours using a visuospatial interference intervention: a follow-up and extension. Eur J Psychotraumatol. 2021;12(1):1953788. doi:10.1080/20008198.2021.1953788
10. Badawi A, et al. Visuospatial working memory tasks may not reduce the intensity or distress of intrusive memories. Front Psychiatry. 2022;13:769957. doi:10.3389/fpsyt.2022.769957
11. Kubickova V, et al. Reducing the number of intrusive memories of work-related traumatic events in frontline health care staff during the COVID-19 pandemic: case series. JMIR Hum Factors. 2024;11:e55562. doi:10.2196/55562
12. Matura JM, et al. Comparing a new visuospatial intervention administered 3 days after a trauma film to reduce the occurrence of intrusive visual memories. Front Psychol. 2025;15:1454086. doi:10.3389/fpsyg.2024.1454086

Study details verified against PubMed and the open-access full text (PMC12916470).

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This article provides general mental health information and is not a substitute for individual medical assessment.

Dr. Lee Wen Pei
Psychiatrist
Moodie 解忧处方笺