“Tetris” is one mighty powerful distraction. Play it for a while, and the game stays in your head long after it’s out of your hands.

I grow weary from having “Tetris dreams” disturb my sleep at night, and so I tend to put the game away for a months at a time after an intense round, but now research out of the University of Oxford suggests those dreams are valuable — they may help keep me sane following a psychologically traumatic event.

The key is Tetris’ ability to distract the brain from processing the traumatic images that flood one’s mind for several hours right after the event. These images can form the foundation for disturbing flashbacks and post-traumatic stress disorder, or PTSD, an affliction also evident in combat-tested military personnel.

According to the Oxford researchers, Tetris influences the same cognition that’s agitated during psychological trauma. Playing the game soon after such trauma may reduce the frequency and intensity of flashbacks and prevent the onset of PTSD because Tetris makes persistent, repeated demands of our “visuospatial skills” to move and place the fast-falling blocks — too many demands, it turns out, for the brain to process other images at the same time.

The research findings are based on observations of just 40 test subjects, so plenty more work needs to be done before the Army starts handing Nintendo DSes to troops just coming off the battlefield, or before hospitals install game consoles in their trauma wards.

In the meantime, maybe someone can do something about these Tetris dreams I keep having.