"We were really surprised," Dr. Bavelier said, adding that as little as 10 hours of play substantially increased visual skills among novice players. "You get better at a lot of things, not just the game," she said.

"Please, keep doing your homework," said Dr. Bavelier, the mother of 6-year-old twins and a 2-year-old.

Dr. Jeremy Wolfe, the director of the Visual Attention Laboratory at Harvard Medical School (news - web sites), who was not involved in the study, said he was intrigued at the idea that "socially dubious games might improve something like general intelligence."


"It might give every 14-year-old something to tell his parents," Dr. Wolfe said. " `Hey, don't make me study. Give me another grenade.' "

Still, he noted that an increased capacity for visual attention was helpful in tasks as diverse as flying, driving, radiology and airport screening.

They carried out four experiments on undergraduates, all of them male because no female shooter game fans could be found on campus.