Time to prove that all those video games I've played do have a purpose! While playing a variety of games, I've observed an interesting application of a real human tendency. For those who are not familiar with the idea of tunnel vision, it's the loss of peripheral vision, creating a "tunnel-like" field of view that narrows around the eye's point of focus. This can be caused by a number of issues with the eyes or brain, but the most common cause is high adrenaline production caused by the fight or flight response.
Anyway, I personally think tunnel vision applies to many situations where concentration is required. In fact, it is often observed in gamers, when their field of view narrows around whatever screen they are using. However, it is even further observed in first person shooters, where only the screen around their weapon's crosshairs is in the field of view. This condition of extreme concentration is often referred to as "FPS goggles" by gamers. I've also experienced this, and find it difficult to switch from a small FOV game such as an FPS or TPS (third person shooter), to a game where you must have awareness of the entire screen such as real-time strategy. Because of my recent obsession with Mass Effect and Bioshock, my Dota 2 game has suffered (at least in the short term). I think that observing the effects of extreme concentration on the mind and body could be helpful in the future, as we live in a world where we need to get stuff done.