Ivan Pavlov - Behavioral Psychology - The Canon

Psychology: Essential Thinkers, Classic Theories, and How They Inform Your World - Andrea Bonior 2016

Ivan Pavlov
Behavioral Psychology
The Canon


BORN 1849, Ryazan, Russian Empire


DIED 1946, Leningrad, Soviet Union


Educated at St. Petersburg University



Ivan Pavlov began his career as a researcher of the salivation response in dogs. His exploration of classical conditioning was a departure from past animal research, not only because of its focus on behavior but also because the dogs were studied for long periods of time without having to be killed for the sake of the experiments. Pavlov soon noticed the phenomenon of psychic secretions—drooling that happened even before food was in the dogs’ mouths. When he began to explore repeated patterns of behavior, he started calling this type of salivation a conditional response (the word conditional, in the original Russian, was translated as conditioned in English, and the term conditioned response has been used ever since).

To understand the fundamentals of Pavlov’s conditioning theory, you need to know a few additional key terms. An unconditioned stimulus is a stimulus (such as meat powder) that will automatically evoke a response (such as salivation in dogs), naturally and without the need for any conditioning to have occurred. A conditioned stimulus is a stimulus (such as a musical tone) that may eventually evoke a response (such as salivation in dogs), but first it will need to be paired often enough with an unconditioned stimulus (such as meat powder).

In his work with dogs, Pavlov showed that, at first, a conditioned stimulus will not automatically evoke a response. For example, dogs have no reason to associate a musical tone with food, and so a musical tone, in theory, won’t make dogs drool any more than a crayon would. But Pavlov’s eureka moment came after he repeatedly paired a conditioned stimulus (a musical tone) with an unconditioned stimulus (meat powder), often enough that the musical tone eventually evoked the salivation response on its own. In other words, even though dogs have no reason to associate a musical tone with food, the tone can be associated with food often enough that it will cause dogs to salivate even when no food has been presented.

Another key component of Pavlov’s theory is his finding that the more times a conditioned stimulus and an unconditioned stimulus are paired, the stronger the association becomes, and the stronger the response that the conditioned stimulus can trigger all on its own. Pavlov showed that repeated pairings are key and that there also has to be temporal contiguity—in other words, the presentation of the unconditioned stimulus (the meat powder) has to closely follow the presentation of the conditioned stimulus (the musical tone). If they’re presented at the same time, or in reverse order, the attempt at conditioning will fail.

Pavlov believed that trace conditioning can occasionally occur if the experience of the conditioned stimulus has already faded before the unconditioned stimulus is presented. He also observed the complete extinction of the response (salivation in dogs) after the conditioned stimulus (the meat powder) had been presented enough times on its own, without the presentation of the unconditioned stimulus (the musical tone), so that the dogs gradually learned that the musical tone was no longer going to bring them food, and their salivary glands eventually stopped reacting to the musical tone. (Nevertheless, Pavlov showed that spontaneous recovery of the association between the conditioned stimulus and the unconditioned stimulus can sometimes take place.)

Pavlov also discovered that the conditioned stimulus need not be presented in exactly the same way each time in order to evoke the conditioned response. Its presentation just has to be similar enough each time. He attributed this phenomenon to what he called stimulus generalization. In other words, the tone doesn’t always have to be exactly the same pitch. Pavlov also taught the dogs what he called discrimination, or the ability to differentiate between gradations of the same stimulus; in this case, the dogs learned that a high-pitched sound from a tuning fork would bring food, and a lower-pitched sound would not. But Pavlov noticed that if he forced the dogs to discriminate too much, by using pitches that were too similar, they would exhibit what he referred to as experimental neurosis and become quite anxious and discouraged.

Pavlov’s holy grail was higher-order conditioning, or using a conditioned stimulus (such as a musical tone) as if it were an unconditioned stimulus (such as meat powder) as the basis for an altogether new round of conditioning. He found, however, that with each level of higher-order conditioning, the response (salivation) lost some of its strength. He believed that second-order conditioning, just one level up from the original conditioning protocol, is attainable but that third-order conditioning is virtually impossible. Nevertheless, the idea of higher-order conditioning served as the foundation for the concept of behavioral chaining, whereby links are created between different layers of stimuli and responses.


Pavlov was not without his detractors. Since he was first and foremost a physiologist, some academics of his day felt that his conditioning experiments strayed too far from real science. Psychologists today, of course, beg to differ.


Though Pavlov is not usually considered to be the true founder of behaviorism, you could certainly make the case that he should be given this distinction. His theories directly influenced John B. Watson, the originator of the term behaviorism, who took a keen interest in classical conditioning. Conditioning theories that came later (such as B. F. Skinner’s operant, or instrumental, conditioning), and that involve reward-oriented behavior rather automatic behavior, also drew on Pavlov’s original ideas. Pavlov emphasized the importance of the role of the environment over that of the mind when it comes to the reasons behind our actions, and behaviorism followed his lead for decades afterward.


Any automatic physiological response in humans is subject to conditioning, which has effects that may be helpful or not so helpful. Sexual arousal, for instance, is often conditioned to occur in direct relation to stimuli that have been associated in the past with sexual arousal. Maybe a couple has a special word, song, or physical signal that serves to set the mood. A less pleasant conditioned response has to do with nausea. Perhaps you once got food poisoning after eating bad mussels, and now the very sight of mussels is enough to turn your stomach. There is even a connection between classical conditioning and the body’s response to drugs and alcohol. Let’s take alcohol tolerance. The term tolerance refers to the need to drink more and more just to get the same effects that a single drink used to provide. Tolerance is thought to occur in part because the body develops a physiological reaction that tries to counteract the effects of alcohol when drinking begins. The body learns to secrete alcohol antagonists, and it takes note of the characteristics of alcohol (notably its smell and its taste) in order to become adept at this process. When someone with a significant alcohol tolerance cracks open a beer, his or her body anticipates the likely effects and goes into action, just as it’s been conditioned to do. The same physiological phenomenon is at work when someone uses heroin after a period of abstinence and then dies from an overdose, even though the amount used was not greater than before. In this case, the body, which has stopped automatically counteracting the substance, is caught off guard.