Subjects: Behavioral health
Flashbacks are vivid, recurring, intrusive and unwanted mental images of a past traumatic experience. They are a sine qua non of Post-Traumatic Stress Disorder (PTSD). Although drugs and cognitive/behavioral interventions are available to treat PTSD, clinicians would prefer to utilize some sort of early intervention to prevent flashbacks from developing in the first place.
The team responsible for the discovery was led by Emily Holmes. The write-up appears in the November issue of PLoS One. Holmes and colleagues had reasoned that the human brain has a limited capacity to process memories, and that memory consolidation following a traumatic experience is typically complete within 6 hours after the event. Holmes’ team also knew that playing Tetris involved the same kind of mental processing as that involved with flashback formation. So they figured if they had people play Tetris during that 6-hour window after the traumatic event, it might interfere with memory consolidation of the traumatic experience. That in turn, would reduce or eliminate the flashbacks.
The idea worked like a charm.
The Experiment: Holmes’ team had 40 subjects watch a 12-minute film depicting traumatic scenes of injury and death, and then randomized the group to either play the classic video game after the movie ended, or to sit there and do nothing. The groups were similar with respect to age, gender and pre-existing psychological make-up.
Subjects in both groups kept track of any flashbacks for a week using a diary. Then, they underwent a formal clinical assessment and various memory tests.
The scientists observed that Tetris appeared to act like a “cognitive vaccine.” Subjects who played the game after watching the movie had fewer flashbacks during follow-up. Amazingly, the Tetris players’ memory of the movie and the associated trauma was the same as the control group. They just had fewer flashbacks.
Extra Credit: To elucidate the mechanisms behind Tetris’ beneficial impact, Holmes’ group performed a follow-up study comparing Tetris with Pub Quiz in a head-to-head match-up. The latter computer game has different mental processing demands than Tetris, and it turned out to actually increase the frequency of flashbacks and other PTSD symptoms.
The authors hypothesized that discussions and debriefing sessions, which constitute the traditional therapeutic intervention in the immediate (that is, within 6 hours) aftermath of a traumatic experience may actually do more harm than good. That’s because these interventions may actually enhance memory consolidation of the traumatic event.