There's nothing quite as intensely manic as reaching the final levels of Tetris and struggling to control those high-speed tetrominoes that plummet to the bottom of your screen like hell-bent comets from the sky. But despite the high-pressure nature of the famous arcade game - or perhaps even because of it - research suggests that playing Tetris and other games like it can help reduce the intrusiveness of emotional memories associated with trauma-related clinical disorders, such as post-traumatic stress disorder (PTSD).

"This work is the first to our knowledge to show that a ‘simple cognitive blockade’ could reduce intrusive memories of experimental trauma via memory reconsolidation processes," said Emily Holmes, senior author of the study. "This is particularly interesting because intrusive memories are the hallmark symptom of PTSD."

Researchers from the Medical Research Council Cognition and Brain Sciences Unit in the UK wanted to investigate whether it was possible to improve upon conventional recommended treatments for PTSD, including various forms of psychotherapy, which often commence at least one month after the patient has experienced a traumatic episode.

A previous study by some of the same researchers had already shown that playing Tetris within four hours of viewing traumatic material could reduce involuntary memory flashbacks to the disturbing content, but the practical applications of these findings were limited.

Obviously, it's not very likely that victims of traumatic personal episodes such as assaults or serious car accidents will be agreeable to playing video games in the hours directly following the incident. So Holmes and her team increased the timeframe to see if traumatic memories could be disrupted 24 hours after having been experienced. In the experiment, volunteers were shown films that contained scenes of traumatic content as a way of “experimentally inducing intrusive memories”.

Twenty-four hours later, the volunteers returned and had their memories of the traumatic film reactivated by watching a series of still images from the film. After the trauma refresher, half the group got to play Tetris, while the other half were asked to simply sit quietly. The volunteers then completed a personal diary over the course of the next week, where they referenced any memories of the traumatic content to which they had been exposed.

The findings, published in Psychological Science, show that the volunteers who played Tetris experienced significantly fewer intrusive memories than those who hadn't been similarly distracted.

Importantly, the 'reactivation' of the traumatic memories (in this case induced by watching stills from the film) alongside the video game session appears to have been a crucial pairing in disrupting the future involuntary recall of negative experiences. Other experiments conducted by the group ran the reactivation and Tetris sessions in isolation, but it was only when they were combined that the volunteers experienced fewer intrusive memories over time.

The researchers theorise that games like Tetris constitute an engaging visuospatial task capable of creating a 'cognitive blockade' that can disrupt the subsequent reconsolidation of visual intrusive memories. Consequently, the recall and impact of negative emotional memories associated with the trauma is lessened in the future.

“Our findings suggest that, although people may wish to forget traumatic memories, they may benefit from bringing them back to mind, at least under certain conditions - those which render them less intrusive,” said co-author Ella James.