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 born

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 capacity of a previously neutral stimulus to elicit a reflex. If a dog is trained to salivate each time that it hears a tone of a specific 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 closely 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 elicit

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 elicit 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 associated 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 Pavlov

gave 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.