"People have hacked it together, but it doesn't really work," he says. "The basic problem is Simulator Sickness. In Valkyrie or any cockpit game or driving game, what you're doing in the real world, assuming you're sitting down, more or less mimics what your brain is telling you you're doing in the game. So you don't get that disconnect, and it's that disconnect that causes sickness. So, the problem with first-person shooters is that you're running or crouching or jumping in the game but not in the real world, and because it's so realistic it can make some people (not everybody) feel nauseated if they start doing it for extended periods of time.""
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