I was reminded of this the other night while playing Wolfenstein 3D on XBLA. If I'm playing a 3-D, exploratory sort of video game, even an FPS, I tend to take my time -- I like to check every nook and cranny for goodies and enemies, and those end-of-level par time comparisons are way out of my normal playing style's league.
I lead myself to believe that I am being very thorough and aware of my surroundings, but every so often something sneaks up on me. And when I turn back to what my mental map indicates should be an empty area, and there's some nasty entity attacking as I turn, I jump. I panic and retreat for a moment before my finger finds the fire button again, and after the skirmish is over, my heart is going a mile a minute.
My wife is also usually laughing at my weird, apparently unmotivated spasm -- the game sounds no different to her, nor is she in the same mental space I am occupying. So she sees the same enemy I'm seeing onscreen, but she is no more surprised by it than by any other enemy I run into. To her, I'm inexplicably terrified of the umpteenth Cacodemon I've seen on this level.
What's interesting is that this reaction can happen in any sort of context, as long as I don't expect the surprise. Playing Dungeon Master in primitive, square-dancing 3-D on the Atari ST was capable of eliciting it, and just the other night Wolfenstein 3D did it to me. It even happens when I'm playing these kinds of games on a handheld -- even though the screen is only a few inches across, it still draws my head into its artificial environment enough to startle me when the unexpected happens. So it's a mental phenomenon, surely -- it's "virtual reality" in its true sense, where my consciousness is fooled enough to respond naturally and reflexively to a sudden threat. It only lasts a split-second, but it's real enough to qualify.
This happens less often with newer games, where enemies have audible signatures as they move about in the surround sound space, but I can still be tricked into rushing into an area I think I've already cleaned out because it LOOKS like an area I've already cleaned out, complete with planted corpses. I open the familiar-looking door, and am met with a horde of enemies. With any luck, I have the presence of mind to shut the door. Or fire back. Or run until my wits are gathered.
It's fun! But as I get older I may have to watch this sort of thing. Who knows what kind of cardiac effect a sudden Nazi guard in my face will cause when I'm 75?