While doing the homework for Welcome to the Fold I've noticed that there is not much in the way of literature about the concept of the role-playing game as a social and psychological phenomenon. Oh, sure, there's Mazes and Monsters*, about which the less said the better, but everything outside of that is more about role-playing in the abstract than the gamification of same. And while stuff like Knights of the Dinner Table is a great comic sociology about gamer culture (and a great zinging of the idiot sexism and prejudice that often bubbles to the surface there), that's not what I'm really aiming for.
Back in college I read John Barth's The End of the Road, about a doctor who prescribes nonsensical role-playing exercises in order to have his patients make a clean break from their former selves and start new lives. It doesn't end well, as you can imagine. But the book felt limited, more an attack on notions that were chic at the time rather than something that had a chance of outlasting its moment. (Most any book that has psychotherapy or theories of same as a major plot element runs the risk of having a very short shelf life.)
In the end, I found a far greater wealth of literature and understanding in a parallel phenomenon: that of religious cults, where the plasticity of personality is key to the cult's ascension to power. I'd already read Robert Jay Lifton in this regard — his books on thought control and brainwashing were also required reading — but it was some of his other books, like Six Lives / Six Deaths, that gave me more insight into the mechanics of specific personalities. In other words, I wanted to get more of a sense of how a specific person's personality would disintegrate and reform itself under close-knit social pressure, especially when it was for the sake of a goal that no one but them could see.
But on the whole, there doesn't seem to be much storytelling about the psychological needs that are addressed by people taking on a gamified role. Or if there is, and I'm completely missing it, then point me in the right direction below (and I'll see about adding some more folic acid to my diet on top of it).
* The nicest thing I can say about it is that if Tom Hanks can live down appearing in the movie made from it, the odds are good most any actor can redeem themselves with a little diligence.