The Premack Principle

How do you find a reinforcer that will "work" with a particular individual? One technique is to observe what the individual chooses to do voluntarily. As a rule, preferred behaviors can be used to reinforce unpreferred behaviors. This is called the Premack principle after psychologist David Premack who proposed the rule. A formal statement of the Premack principle is as follows: high-probability behaviors (those performed frequently under conditions of free choice) can be used to reinforce low-probability behaviors.

What is the Premack principle?

If a rat likes to run on a wheel, you can reinforce a bar-press by allowing it to run on its wheel only after a bar-press. If you have a hamster that always wants to escape from its cage, then you can reinforce the hamster for climbing onto your hand by offering your hand as a way to escape from the cage. The preferred behavior (escaping) is a reinforcer for the non-preferred behavior (climbing onto the hand of a human). This actually works.

Parents sometimes use a variation of the Premack principle. If they want children to eat vegetables (sometimes a non-preferred behavior) they can make a rule that vegetables must be consumed before the children get to eat a dessert (usually a preferred behavior). Similarly, children may be asked to do their homework (sometimes a non-preferred behavior) before watching TV or playing video games (usually a preferred behavior).

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Copyright © 2007 Russ Dewey