Classical Conditioning: Responding to Signals

Imagine that you are reading a menu in a restaurant and your mouth begins to water. Is this an example of classical conditioning? Yes., it is. You were not bom with a tendency to salivate when looking at a menu. This is behavior acquired through experience., and., consequently, a kind of learning. Salivating to words on paper is a conditioned reflex.

Classical conditioning was the first kind of learning to be studied experimentally.

The pioneer researcher into classical conditioning was Ivan Pavlov (1849—1936), a Russian physiologist. Classical conditioning is characterized by the capadty of a previously neutral stimulus to elidt a reflex. If a dog is trained to salivate each time that it hears a tone of a spedfic frequency, then the tone is the previously neutral stimulus and the act of salivating is the reflex. Pavlov achieved his results primarily with a number of dogs that were trained to patiently cooperate with the researcher while being restrained in harnesses in the laboratory.

There are four basic terms, all dosely related, that you need to learn as the foundation stones of your understanding of classical conditioning. These are (1) the unconditioned stimulus, (2) the conditioned stimulus, (3) the unconditioned reflex, and (4) the conditioned reflex.

The unconditioned stimulus is a stimulus that has an inborn power to elidt a reflex. Food in the mouth is such a stimulus. The physiology of the body is such that when salivary glands are stimulated by food, saliva will flow.

The conditioned stimulus is created by the learning process. It acquires a power that is sometimes (not always) similar to that of the unconditioned stimulus.

If a tone precedes food in the mouth a number of times, then the tone may acquire the power to elidt saliva. If a dog salivates when it hears a tone, then the tone is a conditioned stimulus. It can be argued that the dog has assodated the tone with food and that the tone has become a signal conveying the meaning that food is coming soon. Indeed, this is one of the important meanings that Pavlovgave to classical conditioning. He thought of conditioned stimuli as signals.

The unconditioned reflex is an inborn response pattern. A dog has an inborn tendency to salivate when food is placed in its mouth. Salivating under these conditions is an unconditioned reflex. The word response is sometimes used in place of the word reflex. This usage, although common, is somewhat imprecise.

A response to a stimulus is a behavior pattern that suggests a higher level of organization and complexity than that associated with a reflex. Salivating when reading a menu’s description of a hamburger is a reflex. Ordering the item and asking that the meat be well done is a response.

A conditioned reflex is a learned response pattern. If a dog salivates to a tone, then the elicited flow of saliva is a conditioned reflex.

Several important features of classical conditioning should be noted. First, the word conditioning implies a kind of learning that does not require reflection and reasoning. The learning takes place primarily through a process of association.

Infants are capable of classical conditioning. If a baby’s mouth begins to make

sucking motions when a milk bottle is in view, then the sucking motions are conditioned

reflexes.

Second, as indicated above, classical conditioning is not limited to dogs and animals. Although Pavlov used dogs as research subjects, the results of his research can be generalized to human beings.

Third., conditioned reflexes are involuntary. They are outside of the conscious control of the subject.

There are various behavioral patterns associated with classical conditioning.

Three of these are extinction, stimulus generalization, and discrimination.

Extinction takes place when the conditioned stimulus is presented a number of times without the unconditioned stimulus. If a conditioned dog is presented with a tone., it will salivate. However., if the tone is presented without food a sufficient number of times, the tone will cease to elicit the conditioned reflex. The dog has, in effect., unlearned the conditioned reflex. Extinction should not be confused with forgetting. Extinction is an active process that is designed to eliminate a conditioned reflex. The process of actively extinguishing a conditioned reflex is taken advantage of in desensitization therapy.

Stimulus generalization occurs when a stimulus that is similar to an original conditioned stimulus elicits a conditioned reflex. For example., let’s say that a dog is trained to salivate to a pitch that is the equivalent of middle С on the piano. If a pitch the equivalent of D.. a note that is dose to C. is sounded., the dog wiU also salivate. As the pitch goes higher., there may be some salivation. If the pitch gets high enough, salivation will stop. This is discrimination, the subject’s ability to tell the difference between an original conditioned stimulus and other stimuli.

In a classical experiment. Rosalie Raynor, an assistant to John Б. Watson, trained a child to be afraid of a white rat. In subsequent testing, the child., known in the research literature as Little Albert., showed fear reactions (conditioned reflexes) when he saw a different white rat. a Santa Claus mask (with white fur), or a rolled-up white terrydoth dishtowel. This research provides an example of stimulus generalization in a human being.