Video games have racked up their fair share of controversy over the years, with some saying that they desensitize people to violence, others claiming they warrant their own health warning labels, and yet others labeling them a public health threat.

　　However, there are also a number of studies that extol the positive effects of games. Researchers at the University of Rochester in New York have announced findings claiming that playing games, specifically those oriented around action, improve contrast sensitivity function (CSF); that is, the ability to detect subtle differences in shades of grey.

　　While the same researchers had previously found that games improved visual acuity and peripheral vision, the ability to improve contrast sensitivity is significant, given that it was previously held among the scientific community that it could not be improved. CSF ability is often affected by old age or amblyopia--commonly known as lazy eye. Previously, it was possible to ease the symptoms only with glasses or surgery, rather than address the root cause by improving the performance of the eye itself.

　　The research focused on 13 individuals split into two groups playing video games for a total of 50 hours over nine weeks. One group was given action games, including Call of Duty 2 and Unreal Tournament, whilst the other played non-action games, which do not require such precise gameplay actions, such as The Sims.

　　Those in the action group showed a 43 percent improvement in CSF compared to those in the non-action group, whose average was 11 percent. More startlingly, the effect was said to last for months, even after the games themselves had stopped being played.

　　Researcher Daphne Bavelier, professor of brain and cognitive sciences at the University of Rochester, was understandably pleased with the results of the study. "Video game training...may become a useful complement to eye-correction techniques that are routinely used in the clinic to improve eyesight," she said. However, she also noted that "not all video games induce such a benefit, calling for special care in the choice of a clinically relevant training regimen."