The theory on the root cause is that the eyes and the body are reporting different things, (i.e. the eyes say “you just moved” and the body says “nuh-uh, you’re just sitting here”), which causes the brain to go “this is so weird! You must have been poisoned! Time to throw up!”.
But... I am not sure if it’s 100% right.
I’ve looked into it a lot (and I mean *a lot*), because I don’t like getting sick, and I can say this for certain:
- Tiredness affects it. More tired = get sick faster.
- Reticules can help
- It can sneak up on you without warning
- Consuming ginger helps a little. Drugs help a lot but they make you too drowsy to play. And who wants to take drugs in order to play a game? Seriously.
Things that are mysteriously ok:
- I played through the whole of Portal (I really liked this game)
- I played through half of Mirror’s Edge (with the little red dot on the screen switched on)
- I played all the way through Doom and Doom 2 when I was a teenager
- On-rails shooter games, e.g. Time Crisis, House of the Dead, etc
- Elite Dangerous. I think it's because my brain has no real-life experience of space flight
- Most FPS (including Doom 1 and 2)
- That FPS on Nintendo DS that’s set in a mental hospital, I could’t even play that!
- Minecraft, Gone Home, other first-person games that are not shooters.
- I can’t get past the opening cutscene of Bioshock
- Portal 2 :( I really wanted to play it too!
- Stacking, by Doublefine Games, even though it is weird 3rd person - I think it’s the angle
- I got halfway through The Unfinished Swan then suddenly got incredibly sick without warning. Like, I was completely floored for a whole afternoon, world spinning.
- The poo-spraying missions in Saints Row 2 - the rest of the game is fine, as long as I’m driving and not a passenger.
- One time a rotating door in a hotel lobby in real life had the same effect on me, just briefly.
Finally, this condition affects many East-Asian people, and I think that is why there are so many more third-person games released in Japan, and so few first-person games