Ethos Before Analytics

Gamasutra has published a fascinating and insightful piece written by designer Chris Birke that looks at the correlation between neuroscience and game design, particularly because he believes that many developers are "farming" us with dopamine-triggering rewards systems rather than striving to push the medium with thought-provoking stories, artistic merit, and good old fashioned fun. It's a great read, with a few role-playing games used as examples from time to time:
Most behaviorists don't use the words "Skinner Box." Skinner himself didn't want to be remembered as a device, preferring to call it an "operant conditioning chamber." It is a cage used to isolate the subject (usually a pigeon, or a rat) with only a button to operate and a stimulus (a light, for example) to be learned. Pressing the operant (button) releases a reward (food), but that's reliant on pressing it correctly in response to the stimulus.

It was with this that Skinner explored the nature of learning and, further, how to maximize or disrupt the compulsive behaviors of his subjects. The results, in short, showed that the schedule of rewards in response to stimulus greatly affected how animals (like you and me) responded to their training. The most compulsive behavior was not driven by "fixed ratio" rewards, where a stimulus meant a consistent prize for correct actions, but instead by a semi-random "variable ratio" schedule. Maybe you would win, or maybe not. Keep trying, just in case -- you'll figure it out eventually.

If you have been designing games at all in the past few years you ought to be familiar with this. Applying and combining the results of these studies have been proven to work. No one can deny the incredible feeling you get upon hearing the familiar "ting" (YouTube link) of a rare ring dropping off an enemy in Diablo. It's the combined reward of the long term chase for better stats with the instant gratification of a high pitched chime over the clank and groans of battle. It's rare and semi-random.

You can't argue the benefit of front-loading content onto the learning curve like in Rift (or any other MMO) either. Dishing out rewarding content more slowly in the late game not only maximizes its use, it's fitting nicely to the documented results of the most compelling reward scheduling. Just add some compelling random combat encounters to keep it fresh. Reviews (for example, Gamespot's Review) call this out as good design, because it's more fun that way, right?

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By this theory, the largest dopamine rush accompanies the first few times you play. If you've ever felt a compulsion to rush home and play a game all day, you are likely getting a hint of what a strong addiction feels like. Afterwards, the combined effects of acclimation and inhibition curb further dopamine release.

Can a game lay down enough conditioning over time that begin to match the levels of reinforcement seen in drugs that immediately release dopamine? Perhaps, and we have strong profit motivation to see if this is true. It's reasonable to assume some people can be trained to compulsively play games.