This is why you have to play cs.

kinda old but still true!

"Researchers now say they may have found a way to improve contrast sensitivity naturally with the help of an unlikely source—video games."

"Those who played the action-packed video games such as  Unreal Tournament 2004 by Atari and  Call of Duty 2 by Infinity Ward experienced an improvement in contrast sensitivity, while those playing  The Sims 2 by Electronic Arts did not."

source: http://www.scientificamerican.com/blog/post.cfm?id=what-are-video-games-good-for-possi-2009-03-29