1. Lesson 24 What is behavior?

2. In school, behavior means being good or bad. To a scientist, behavior means all kinds of actions. It means how we react to stimuli. It also means how we learn.

3. Scientists study behavior. They try to find out why we behave the way we do. They also try to find out how behavior can be changed.

4. One of the scientists who studied behavior was a Russian scientist named Ivan Pavlov. About a hundred years ago, Pavlov experimented with dogs.

5. He knew that dogs drool every time they see or smell food. This is a normal reflex response. Pavlov wanted to find out if this reflex could be changed. This is what he did:

6. Pavlov rang a bell every time he brought food to the dog. Each time he brought food, the dog drooled. Remember: food always makes dogs drool. He did this many times.

7. Then…………He just rang the bell. He did not give the dog any food. What do you think happened? The dog drooled, even though there was no food in front of him!

8. The dog had learned that the bell always meant food. The bell had now taken the place of food as a stimulus that causes drooling.

9. A behavior where one stimulus takes the place of another stimulus is called a conditioned response. Pavlov’s dog was conditioned to respond to a new kind of stimulus.

10. Conditioning is a very simple form of learning.