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Discovering Psychology: Updated Edition


Learning is the eighth program in the Discovering Psychology series. This program discusses the basic principles of how we learn; classical, instrumental, and operant conditioning; and the role that stimuli and consequences play in learned behavior and habits. You'll explore how renowned researchers Ivan Pavlov, B. F. Skinner, Edward Thorndike, and John B. Watson contributed to what we know about human and animal learning.

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Experiment: How Pigeons Learn Self Control

In the study of behavior, operant behavior is affected by the environment, and operative conditioning is used to reinforce behavioral change. Behavioral psychologist Dr. Howard Rachlin used operant conditioning to study ways of developing self-control in pigeons.

Dr. Rachlin chose to use pigeons because they can be a particularly impulsive subject. The experiment prompted the pigeons to peck one button once for a small bit of food, and another button 15 times for a larger amount. When presented with a choice between a small but immediate portion of food or a large but delayed portion of food, pigeons chose the small, short-term reward. But when Dr. Rachlin’s team put a pigeon in a box with two buttons that both required 15 pecks for any amount of food at all, the pigeon ultimately chose the button that offered the larger amount.

Eventually, the pigeons learned to choose a larger amount of food by pecking a button 15 times and then waiting four seconds for the food, as opposed to choosing a more immediate but smaller reward. Dr. Rachlin’s experiment illustrated that a pattern of behavior can reinforce the choices that lead to self-control. Parallel human experiences include healthy behavioral changes such as cultivating good exercise habits, quitting smoking, or finding alternative outlets for anger and stress.

Mary Ann Chapman expands on Dr. Rachlin’s findings, and how the principles of operant conditioning can be used to overcome bad habits or addictions.


Classical Conditioning: A form of learning in which behavior or conditional response comes to be elicited by a stimulus that has acquired its power through an association with a biological stimulus, such as food, or repetition. Also called Pavlovian conditioning, after the Russian physiologist, Ivan Petrovich Pavlov, whose experiments with dogs revolutionized the concept of memory and response.

Instrumental Conditioning: Learning about the relationship between a response and its consequences.

Law of Effect: The basic law of learning that states that the power of a stimulus to evoke a response is strengthened when the response is rewarded, and weakened when it is not rewarded.

Operant Behavior/Conditioning: A variation on instrumental conditioning in which behavior operates upon the environment and produces consequences, and conditioning manifests as the change that takes place when those consequences have a particular effect.

Reflex: A natural reaction to an external stimulus that causes a physical response. Also an unlearned response induced by specific stimuli that have biological relevance to the organism.