http://www.clickertraining.com/taxonomy/term/222/9 The weakening of behavior through non-reinforcement or “ignoring” the behavior. In extinction, nothing is added or removed from the environment. For example, a treat lies on the other side of a fence. A dog reaches his paw under, but cannot reach the treat. Because reaching for the treat doesn’t work—because it isn’t reinforced through success—the dog will eventually quit reaching for the treat. en