Video games are not all bad, according to a report from U.S. shrinks.

Amongst other things, playing video games improves manual dexterity among surgeons, making them faster and less likely to make mistakes, the Annual Convention of the American Psychological Association was told.

Psychologist Douglas Gentile of Iowa State University said that there are several dimensions in which games have effects, including their content, how they are played, and how much. He said that games are not 'good' or 'bad,' but are powerful educational tools and have many effects we might not have expected they could.

Gentile said that Laparoscopic surgeons who played video games were 27 percent faster at advanced surgical procedures, and made 37 percent fewer errors, compared to their non-gaming colleagues. However, it was not all good. Students who played violent games were more hostile, less forgiving, and more apt to view violence as normal, than peers who played non-violent games.

Students who played "pro-social" games got into fewer fights at school and were more helpful to other students, the researchers reported.