Playing the computer puzzle game Tetris immediately after experiencing a traumatic event appears to reduce the effects of traumatic stress. In a recent study, volunteers were exposed to distressing images. Half of the subjects were later asked to play the popular video game for 10 minutes. Those who played experienced fewer flashbacks during the week following their exposure. The researchers believe that recognizing the shapes and moving the colored blocks around in the computer game competes with visions of trauma and may interfere with the way sensory memories are formed.