I play first-person shooters online. After 3 years of playing I became so good that I was often accused of cheating. However the experience was of significant benefit for my alertness in traffic : I am a pedestrian and my brain has become wired to see every car as a potential threat (thanks to videogames). Anyhow, my main point is this :
While walking, I saved my identical twin brother from two potentially fatal accidents ! Also, on 7 other occasions I was able to spot a misbehaving car long before my brother did.
He does not play video games. We are identical in every other way, even down to our choice of physics degrees and tastes. He is essentially my clone.
As a physicist, I can assure you that these car incidents are not a coincidence.
As for the detrimental effects of videogames, I see none : I have no problems with my social life. I get straight 'A's in all my courses, including several rather advanced graduate quantum mechanics courses. I play less than 1 hour per day, and not every day. By spreading out the 'reflex training' in games my brain can better assimilate the game-knowledge when it 're-wires' its short term memory during sleep. Make sure you get the full 8-hours of sleep, as many students will tell you, this is an essential ingredient for achieving high marks in your studies and for retaining the knowledge over the many years required in a University degree. Otherwise many learned facts eventually 'evaporate' from your brain.
John Talbot
Physics Dept.
University of Ottawa
Canada
http://laserstars.org