I lifted this from the web, Jayrod, hope it helps
It's Not the Content...
Having played FPS games for a number of years, feeling nauseous was never an issue. However, in more recent times with the likes of Half-Life 2, Crysis and F.E.A.R, I have to confess at limiting my game time on these titles to around 30 minutes. Why? Because playing them makes me feel ill.
No, it’s not because of the game’s content, the sight of blood or the sometimes-gratuitous violence in the games that cause this feeling. The sensation is caused by Simulation sickness, which is a condition where a person suffers a condition similar to motion-sickness through playing video games or other computer simulation.
Theories
There are a few theories which surround the phenomenon. One theory – and perhaps the most common – is that the illusion of motion created by the game environment, combined with the lack of physical motion of the subject causes some level of disorientation in the Area postrema. This is the part of the brain that controls vomiting and for reconciling differences between vision and balance. In our bodies, it is the inner ear which regulates balance when we move; however when there is no movement detected by our ears but movement detected by our eyes then we have a problem. In these instances, the brain’s natural defense is to assume some form of toxin has penetrated the body and tries to expel it.
Of course, there’s no toxin; the effect is down to a clash of the senses whereby what we see on the screen cannot be tallied by the ear and vice versa. Other theories put forward suggest the blame lies at newer technologies such as widescreen TVs and monitors for distorting the field of vision in games, especially in confined environments such as alleyways or corridors.
The 'Bob' Effect
From a gamer’s view, the most likely cause of Simulation sickness is the ‘bob’ effect, which is manifest in the FPS genre by the illusion of the character’s moving, through their weapon and the scenery ‘bobbing’ up and down slightly with each step taken. As FPS games are generally fast paced, then the effect of motion is accelerated to the point where eyes and ears get out of sync with one another and so become disoriented.
Remedies
So, what can you do to combat Simulation sickness? Some remedies include:
Taking Ginger – ginger root is a very effective anti-emetic cure and sipping ginger tea can help alleviate the symptoms of nausea.
Sit Further Back from your display – increasing the height and distance you view your monitor or TV from helps readjust the field of view.
Turn off the ‘bobbing’ effect – some games allow you to turn off or reduce the amount of movement on the screen.
Reduce your mouse sensitivity – helps to minimise the amount of ‘camera’ shake.
Play in a well-lit room – dark or dimly lit playing environments can make the disorientation worse.
Move with the game – moving with the game helps give the inner ear the illusion of physical movement and so the brain can easier reconcile with the visual imagery.
Keep hydrated – dehydration can cause headaches, which could impact on the brain’s ability to keep focussed.
As with all computer games, not playing while tired and taking regular breaks from the action can also help alleviate symptoms. It might also be worthwhile paying a visit to an optometrist to make sure you don’t require glasses, while certain over-the-counter medications for motion sickness may also help.
Read more:
http://www.brighthub.com/video-games/pc/articles/8149.aspx#ixzz0UCQ84wKY
