30. People’s Behavior Can Be Shaped

There is a story that makes the rounds in psychology classes about how a class of students at a college used the behaviorist idea of shaping to get the professor to leave the classroom in the middle of his lecture: The students arranged this among themselves ahead of time, before class started. When the professor came in to start the class, the students ignored him (no reinforcement) unless he looked toward the door. At some point in the lecture, he randomly looked toward the door. When he did, the students looked attentively at him for a moment. Every time he looked toward the door, they would look up attentively (looking up attentively was the reinforcement). Before too long, the professor was looking at the door a lot. At that point, the students stopped reinforcing by looking toward the door. Instead, they would look up attentively only if the professor took a step toward the door. At some point in the lecture, he took a step toward the door, and then the students looked up attentively.

This shaping of the professor’s behavior continued (he moves closer to the door, he moves his arm toward the door, he touches the door, and so on) until the professor actually left the room.

I’m pretty sure it’s an urban legend that was created by a psychology professor who was trying to explain shaping.

The official description of shaping is “the differential reinforcement of successive approximations.” The idea is that if you want to establish a new behavior, you have to first reinforce an earlier behavior that will lead to the behavior you are looking for. Once the earlier behavior is established using reinforcement, then you stop reinforcing that behavior and only reinforce a behavior that moves you closer to the final, desired behavior.

Using Shaping In a Presentation

It’s actually possible to use this idea of shaping in your presentation. Let’s say that you are teaching an interactive session. You want your audience to participate and be comfortable interacting with each other, but they are slow to do so. You could shape the behavior in this way: Ask the class a question and then smile or nod when a participant looks at you (attention from the presenter is the reinforcement here). Later on ask another question, but don’t smile or nod until someone raises a hand. Later on ask another question, but don’t smile or nod until someone speaks up. If you keep this up, at some point they will just be interrupting and not waiting for a question to even be asked (assuming that is what you want!).