Behavioral theory is a psychological approach that emphasizes the role of conditioning in learning and motivation. Conditioning occurs when an animal or person learns to associate a particular stimulus with a particular response. The most common type of conditioning is classical conditioning, which was first described by Russian physiologist Ivan Pavlov. In classical conditioning, a neutral stimulus (such as a bell) is paired with an unconditioned stimulus (such as food) that naturally leads to an unconditioned response (such as salivation). After repeated pairings, the neutral stimulus comes to elicit the unconditioned response, and the animal or person is said to be conditioned to the stimulus.Behavioral theories of learning and motivation have been very influential in psychology, particularly in the areas of education and therapy. Behaviorists such as B.F. Skinner believed that all behavior is determined by its consequences—that is, whether it is reinforced or punished. According to this view, we learn to repeat behaviors that are reinforced and to avoid those that are punished. Behavior therapy, a type of psychological treatment that is based on behavioral theory, uses principles of conditioning to help people change unwanted behaviors.