A new study from the Center for Visual Studies at the University of Rochester in New York, indicates that playing action first person shooters like Unreal Tournament and even Call of Duty 2 improves visual perception. Non-fps games however yielded little effect in the experiment.
In 2002, Daphne Bavelier, a cognitive neuroscientist at the University of Rochester in New York state, found that playing action video games improved visual attention skills (ScienceNOW, 18 April 2002). This time she compared avid gamers with nongamers on a type of visual perception called contrast sensitivity. It allows people to make out objects in dim lighting and to distinguish objects from a busy background.
The article also implies that the research will continue further on the specifics and differences of the effects of playing various types of first person shooters.