Japanese scientists also found that they could be short-tempered, experience problems concentrating and have trouble getting along with their mates.
Professor Akio Mori and his team studied 240 people for several months between the ages of six and 29.
He looked at their brain waves and the activity it produced while playing the games.
He said that the level of activity in the part of the brain that controlled emotion went up the longer games were played.
Hardly surprising when you think how frustrating it can be trying to finish a tricky level of your fave game!
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