Scientists have discovered that men regress to their caveman instincts when playing computer games, because the area of the brain linked with the desire to conquer becomes activated.
This, they believe, is why men are more likely to become obsessed with their computer consoles than women.
Both sexes were monitored during a study, in which they had to play video games while hooked up to an MRI scanner to record brain activity.
The MRI data showed that the brain’s mesocorticolimbic centre, the region typically associated with reward and addiction, was stimulated in both men and women.
However, male brains showed a significantly greater activation that only grew as they proceeded with their game.
Dr Reiss, of Stanford University, California, said the research also suggested males are more likely to feel rewarded by computer games.
He said: "These gender differences might help explain why males are more attracted to, and more likely to become 'hooked' on, video games than females".