"Tetris can prevent post-traumatic stress disorder," reports The Daily Telegraph. An early stage study found that people who'd been in traffic accidents who played the popular computer game while waiting in A&E for treatment had fewer intrusive memories during the following week.

Researchers believe the brain lays down visual memories in the hours after a traumatic event. These can resurface as intrusive and distressing flashback memories during the days and weeks following the event. Intrusive memories of this sort are one symptom of post-traumatic stress disorder (PTSD).

Tetris, or similar games of its type such as Candy Crush, require a high degree of visual attention. The idea of the study is that these types of activities may lessen people's intrusive thoughts after a trauma, such as a car crash. This in turn might lower their risk of developing PTSD.

It's important to point out that the treatment with Tetris was not intended to wipe out people's memories of the accident. They were still able to remember the accident when they voluntarily thought about it. The treatment is designed to reduce unwanted, intrusive and distressing memories which pop up when people are trying to do other things.

The study authors say the computer game could act as a "cognitive vaccine" to help prevent psychological illness. There are many different types of trauma experience and this technique may not be appropriate for all of them.

Where did the story come from?

The study was carried out by researchers from the University of Oxford, Ruhr-Universitat Bochum, University of East Anglia, Karolinska Institutet in Sweden and Oxford Health NHS Foundation Trust.

It was funded by grants to the researchers from the National Institute for Health Research, Medical Research Council, Karolinska Institutet and Wellcome Trust.

The study was published in the peer-reviewed journal Molecular Psychiatry, on an open-access basis so it is free to read online.

The study was widely reported in the UK media; with some inaccuracies. The Sun claimed that playing Tetris "can protect soldiers from debilitating post-traumatic stress disorder". But the study did not include soldiers in combat. Also, most of the reports said the study showed Tetris could prevent PTSD, although this was not demonstrated by the study results.

What kind of research was this?

This was a small randomised controlled trial (RCT). RCTs are the best way to compare the effects of one treatment with another. In this case, researchers wanted to know if playing Tetris would have more effect than a control intervention, in which people wrote down their activities in the A&E department on a worksheet.

However, this was an early stage trial primarily designed as a proof-of-concept; that is to see if a treatment could have potential. Further larger trials would be warranted.

What did the research involve?

Researchers recruited 71 adults (average age 40) admitted to A&E within six hours of being involved in or witnessing a road traffic accident – either as drivers, passengers, pedestrians, cyclists or motorcyclists.

Study participants had to be fully alert and sufficiently well and mobile enough to play a computer game. Those who had lost consciousness for more than five minutes, had previous severe mental illness, were intoxicated or experiencing suicidal thoughts were excluded.

Half the people were randomly allocated to play Tetris for around 20 minutes and half to the control group. Everyone received diaries to complete for seven days, in which they noted any intrusive memories about the accident.

They were also assessed for symptoms of post-trauma distress after one week, and for PTSD symptoms after a month. Researchers looked for differences in numbers of intrusive memories and post-trauma symptoms, between the two groups.

People assigned to play Tetris were shown how to do it, then asked to play for a minimum of 10 minutes without interruption. They were first prompted to think about the most distressing image that came to mind when they thought about the accident. Researchers say they believe that this memory "trigger" may be crucial to the success of the treatment.

Those in the control group were not given a memory trigger, but simply asked to log on a work sheet everything they'd done since arriving at A&E, and how long it had taken.

All follow-up was self-completed. Participants posted back the intrusive memory diaries, and completed questionnaires online or via the post. They were also asked to complete a questionnaire about their experience of the intervention.

What were the basic results?

People from the Tetris group had fewer intrusive memories during the week after the accident:

people who played Tetris had an average 8.7 intrusive memories (standard deviation 11.55)

people in the control group had an average 23.3 intrusive memories (standard deviation 32.99)

This was the main measure the study was designed to assess. However, researchers also looked at people's post traumatic distress symptoms and anxiety and depression symptoms, one week and one month after the accident. They found no difference between the two groups on all but one symptom (about intrusive memories) after one week, and no differences at all after one month.

In feedback, people said they found playing Tetris very easy, very helpful, and not distressing or burdensome. The researchers say there were no adverse events from the treatment.

How did the researchers interpret the results?

The researchers said the intervention was "feasible and acceptable" for use in A&E, because it is short, low cost, simple and flexible to administer. The say other visual games, such as Candy Crush, or simply drawing, could also be used.

Their previous research suggested that the important thing is that the task is visually demanding, as opposed to a verbally demanding task such as filling in crosswords or reading.

They explain the lack of difference in effects after one month by saying the trial was not big enough to show an effect at that point, and call for bigger studies, "designed to test whether effects extend to one month or longer".

They conclude that the intervention "offers a low-intensity means that could substantially improve the mental health of those who have experienced psychological trauma."

Conclusion

Involvement in a traumatic event such as a traffic accident can have long-lasting effects on mental health. Some people have months or years of distressing, intrusive flash-backs, feelings of guilt or helplessness, anxiety and depression. At present, there are no treatments that can be given straight away to prevent such long-term effects.

The lack of long-term effects in the study results mean we need to be cautious about claims that playing Tetris could "prevent" PTSD. Limitations of the study – such as an untested control intervention, and the relatively small number of participants – mean this is an experimental study to establish a theory, not proof that the treatment works.

Intrusive memories are not the only symptom of PTSD but are thought to be an important part of it. We don't know whether interfering with the laying down of these intense, distressing visual images can prevent PTSD.

However, a simple treatment to reduce the recurrence of these memories – even in the short term – might reduce people's suffering in the immediate aftermath of a trauma.

The same researchers published a paper looking at use of Tetris after trauma, as we reported back in 2009, but in that case they relied on "inducing" trauma by asking people to watch films of traumatic events. This is the first time the intervention has been tested in people who have actually experienced real life trauma.

However, there are many different types and severities of trauma that could carry a risk of PTSD. This study, though assessing real life trauma, only looked at adults involved in a road traffic accident but who were fully conscious and able and willing to play a computer game.

We need to take care not to generalise the possibilities of such an intervention too far at this stage. The appropriateness of offering computer games may be very different for people who are victims of assault, for example. The potential effects and even harms could be different in these people.

Even relatively "minor" traumatic experiences such as a dog bite or a nasty fall can trigger a pattern of intrusive memories in some people. Treatments such as cognitive behavioural therapy may help people experiencing long-term mental health problems after traumatic experiences.

And, interestingly, the concept behind this study chimes with a relatively new treatment concept for PTSD known as eye movement desensitisation and reprocessing (EMDR), which involves a similarly visual intensive process.

Read more about the treatment of PTSD.

Analysis by Bazian

Edited by NHS Website