"My freshman college roommate bought Civilization when it came out in '91," my friend Rob recalls. "We brought it back to his dad's place. His dad had just moved some stuff, so there was only one chair in front of a desk with the computer. Mike installed Civ and started playing. Another friend and I stood behind him, watching and kibitzing. I asked what time it was; my friend said 8:30 p.m. Next thing we knew, Mike's dad woke up and asked us what the hell we were doing, standing around a desk at 5:30 in the morning."

Immersion: intense focus, loss of self, distorted time sense, effortless action.

Game designers and reviewers universally recognize immersion as a signal virtue of games, perhaps the central virtue. Nonetheless, they seldom analyze the idea. Possibly, recognizing the elusiveness of immersion, they fear (in Alexander Pope's phrase) breaking a butterfly upon a wheel.

The ones who write a lot about immersion are tenure-track academics in the humanities, the new breed of "videogame theorists." They break butterflies for a living. Yet, you'd look hard to find anyone less likely to explain immersion. Why? Let the analysis draw you in ... come, drift free of your body ...

This is Your Brain on Immersion

For starters, academic game theorists argue endlessly the importance of "narrative."

Many gamers can name a favorite story presented in a computer or videogame, whether the Zelda or Fighting Fantasy series, roleplaying games from BioWare or Origin, a classic adventure like Grim Fandango or The Longest Journey, or even the old Sierra Quest series or Infocom text adventures. These games use a storyline to assign meaning to your actions. Playing your own favorite game, did you feel caught up in a compelling narrative, the way you'd be mesmerized by a terrific book or movie? It felt like that, didn't it?

Except it didn't, really. When the game ended and you returned to reality, you felt spent, maybe exhausted, as if after a workout. In contrast, when the novel or movie ended, you probably felt like you'd awakened from a powerful dream. (The exceptions are horror and action stories, which can wring you just as dry as a game.) In both cases, you felt stiff, but the game immersion left you shaky for hours. Some kinds of games might have influenced your behavior long afterward. How many Quake or Unreal players, immediately after they finish a marathon deathmatch, head to the kitchen for a snack - and peer carefully around the door jamb, scouting for enemies? Are you nodding? Uh-huh. Bet that didn't happen after you watched Return of the King.

Think how you feel when, after a long struggle through a shooter level, you reach some non-player character and suddenly the game shifts to a cut scene that advances the narrative. Maybe you're interested, maybe relieved or annoyed; regardless, you sit back, draw breath and feel different. Your mode of thinking has abruptly changed. You're no longer immersed.

This happens even in non-shooters, and even when the game's story is good. The narrative may inform your actions - for instance, it may present you with a choice of allies or victims - but obviously you aren't sitting back and giving yourself over to the storyteller, as you do when reading a good novel.

Narratives and games inspire contrasting kinds of immersion; different brain-states. Caught up in a story, you are cooperative, yielding, in a state akin to hypnosis. In a game you are ceaselessly active, in a state of flow. Proposed in the 1990 book Flow: The Psychology of Optimal Experience by Hungarian-born psychologist Mihaly Csikszentmihalyi (pronounced, he says, "chicks send me high"), flow is the zone, the groove - an enjoyable feeling of oneness with the activity.