Slotting the colored blocks of Tetris into their places is both satisfying and addicting. But it could also be healing. If the findings of one small study pan out, a simple game of Tetris could prevent traumatic from taking hold in brain and reoccurring as flashbacks, reports Jessica Griggs for New Scientist.

Griggs explains the problem the game might help alleviate:

If an event is particularly traumatic, vivid memories of it can reoccur. These intrusive flashbacks are distressing for anyone, but in a proportion of cases they can persist and contribute to PTSD. For example, about half of people who have been raped go on to develop PTSD, as do a number of asylum seekers and people who have been tortured. About 20 per cent of people who have been in a serious car accident are affected by the condition.

The standard of care for post-traumatic stress disorder is typically revisiting memories in order to overcome them, but in the future, drugs could help sufferers forget. But in 2009, a research group led by Emily Holmes at the medical Research Council Cognition and Brain Sciences Unite in Cambridge, UK, found that playing Tetris within four hours of experiencing a traumatic event led to fewer flashbacks according to Jamie Condliffe at Gizmodo.

Of course, playing a game within a few hours after experiencing a traumatic event — a rape, for example — isn’t really possible. So, Holmes and her colleagues decided to see if the effect could also take hold if the game was played a day later. A night's worth of sleep gives the brain a chance consolidate memories, or store them more permanently in the mind. First, the team showed video clips of distressing events to 56 people. "They were clips from public safety videos, for example, so they were designed to stay with you," Holmes told New Scientist.

A day later, the study participants came back into the lab and looked at still images from the clip to make the memory fresh. Recalling the memory makes it more malleable in the brain, which is why therapy can work. Holmes likened the process to warming up plastic and remolding the material.

Then, half the participants played 12 minutes of Tetris. The other half sat and waited. Over the next week, the Tetris-playing group reported fewer intrusive memories of the disturbing video, which were defined as spontaneous and unbidden scenes appearing in their mind. On average they experienced between one and two of those intrusive memories or flashbacks, whereas the group that did nothing experienced five flashbacks on average. The team published their findings in the journal Psychological Science.

Tetris isn’t some magical bad-memory erasing game — the researchers suspect that any visually stimulating and enjoyable game might work. However, they also write that the videos are a poor substitute for genuine traumatic experiences.

Still, if playing a game helps, it would be a simple intervention. A short game-playing time could be offered to people who have been raped while they wait at a police station or to asylum seekers at a detention center, Griggs writes for New Scientist.

"Think of it like hand washing," Holmes told New Scientist. "Hand washing is not a fancy intervention, but it can reduce all sorts of illness. This is similar — if the experimental result translates, it could be a cheap preventative measure informed by science."