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Example 2: Making an Addictive Game

Now let us assume that we have a more exciting goal of, "Create a game that gets the player to play for as long as possible." Again, notice the goal includes the gamer. A quick brainstorm of fields of study that involve "getting someone to do something for as long as possible" yields: coercion or torture, marketing, and psychology of motivation or addiction. Psychology is the obvious choice, as psychology can explain why marketing and coercion work.

We open an introductory psychology textbook to the chapter on motivation and addiction. Two principles seem appropriate:

  1. Operant Conditioning. In a nutshell, operant conditioning is the psychological principle that states that a person is motivated to do or not do an action based on whether they have been rewarded or punished for that action in the past. Operant conditioning principles also explain how to schedule rewards in order to maximize motivation to perform the action. These principles have been discussed in the context of games in other Gamasutra articles, and I refer you to them.
  2. Maslow's Hierarchy of Needs. Maslow's theory dictates that people are first motivated to satisfy basic needs. When these are satisfied, people try to achieve higher and higher needs. The needs, according to Maslow and beginning with the most basic are: Physiological Needs such as hunger, Safety, Belonging and Love, Esteem and Approval, Self-Actualization.

We can use these two principles that have been "proven" by scientific methods, to both create addictive games and analyze the addictiveness of existing games. There are other psychological principles of motivation: chemical addiction, sexual motivation, and the Opponent Process theory may be applicable to games. However, I ignore them for brevity's sake. The Opponent Process Theory seems particularly applicable, as it deals with both success and failure and should be thought about further.

In order to briefly validate that these two principles apply to games, we need only look as far as Everquest and the Sims. Both unconsciously (or possibly consciously) utilize these principles to great effect. Everquest is well known for its addictive properties and its ability to get players to play for very long periods of time. I encourage the reader to attempt to list all of the uses of operant conditioning in EQ. A few examples are the use of variable schedule reinforcement in striking a blow, killing a monster, getting good treasure, finding good monsters, and skill crafts just to name a few. Maslow's Hierarchy also applies to EQ. Newbie players struggle for safety then as they become stronger, they begin to form friendships and look for belonging and people to party with. Finally, as the players begin to reach top levels, they begin to look for esteem and approval, often in the form of distinctive looking armor, weapons, and distinguished powers and levels. Thus players are allowed to advance up the hierarchy and are motivated to reach the top.

The Sims use of Maslow's Motivations is blatantly obvious. New characters struggle for physiological needs such as food, sleep, and bodily functions. As the players become richer, they can focus more on safety, then belonging and love, then esteem and approval; even if the love, esteem, and approval are only from other Sims. The use of operant conditioning is less obvious, but still present. Rewards take the form of home improvement, neat object animations, and friends. These rewards also follow a conditioning schedule, making game play addictive.

Implementing operant conditioning in a game in order to make it addictive is pretty easy. Simply ensure that your game doles out rewards following a variable interval/variable ratio schedule (look at Everquest, Diablo, or a slot machine in Vegas to see some successful examples of operant conditioning.) Implementing Maslow's Hierarchy in a game is a slightly more difficult, less tangible goal. Allowing players to express their "affection" to other players, allowing players to show team allegiance, and allowing players to track their own success (and ensuring that players eventually succeed) are all good ways of allowing players to feel that they are advancing up Maslow's Hierarchy, thus encouraging them to play further.

These two examples demonstrate the relative simplicity of generating principles that are both useful in a game design and game analysis.


Unfortunately, many do not agree with this approach. First, some may argue, successful games have been designed without understanding underlying principles, thus why use them at all? Certainly, many game designers, such as Will Wright, seem to have an innate ability to design games without the use of established principles (at least I assume that Will Wright did use psychology textbooks in designing The Sims.) However, arguing against using principles simply because some people have succeeded without them is similar to arguing a return to alchemy, simply because some alchemists had some success (albeit in this case, Will Wright is one damned talented alchemist.) Chemists have almost completely replaced alchemists, despite alchemists' limited success, because the chemists' approach is simply more efficient and allows a better understanding of underlying issues. This is not to say that this approach to game design will ever replace the Will Wrights of the world. This approach will simply help the rest of us.

The second argument is that game design is an art not a science, therefore, established principles should not apply. Game design is an art - however, even arts have established principles. Painters use the principles of perspective to portray three dimensions, while most scriptwriters use general principles of conflict and climax in order to keep their plots moving. Plus, the principles borrowed from other fields will never rob game design of its creativity. If, for example, we tried to create a game that only used operant conditioning sans creativity, all we would have was a dispenser with a lever that popped out food pellets using a variable reinforcement schedule. Nobody would be willing to "play" this "game." No, great amounts of creativity must be applied to these principles in order to make them fun and enjoyable. However, these principles give a basis of understanding with which to work from.

The final argument is that game designers don't have time to muck around with psychological principles. First, the two examples that I used above took about fifteen minutes each to research - certainly designers have fifteen minutes to spare. Second, by understanding fundamental principles, designers can avoid some guesswork and therefore save time in the future. Finally, if game designers are willing to share the principles that they have discovered, then other game designers will not have to "muck around" with psychological principles. Rather, they will simply be able to read about them in the context of game design.


The process of borrowing principles from other fields is as simple as stating an objective, brainstorming applicable fields, choosing appropriate principles from those fields, checking those principles against existing games, and implementing.

Would you rather be an alchemist or a chemist?

Alexander Jhin was almost a psychology major at Yale University. Instead, he became a computer science major. He has worked on the Asheron's Call and Zone.com teams and is currently the head of a small, independent, international team. He will be working for Microsoft's DirectX in the coming year. He can be reached at alexander.jhin@yale.edu and he welcomes any comments, especially negative ones.

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