TOEFL Speaking Task 3

The concept of 'behavioral momentum' refers to the tendency of established behaviors to persist even when faced with challenges or changes in the environment. Just as physical momentum keeps an object moving, behavioral momentum describes how a strong history of reinforcement for a particular behavior makes it resistant to disruption. When a behavior has been consistently reinforced, it becomes more likely to continue, even if the original reinforcement is no longer available or the situation changes. This principle is often used in psychology to understand why habits are hard to break and how interventions can be designed to alter persistent behaviors.

Professor: Now, let me give you an example from a study I conducted. We had two groups of rats pressing a lever for food. For Group A, we provided a high rate of reinforcement—every press got a pellet. For Group B, reinforcement was intermittent—only every fifth press. After two weeks, we introduced a distraction: we started playing a loud noise intermittently during the sessions. The rats in Group B, with the weaker reinforcement history, stopped pressing the lever almost immediately when the noise started. But Group A, with the dense reinforcement schedule, continued pressing the lever despite the noise. Even when we stopped giving food altogether for a short period, Group A kept pressing for a while, whereas Group B gave up quickly. This shows how a strong history of reinforcement creates momentum—it makes the behavior resistant to disruption.