468 Part VI Learning-Cognitive Theories
a rat does not generalize to fear of a block; and fourth, fear of a furry white rat can
generalize to other animals as well as to other white hairy or furry objects.
The key to this classical conditioning experiment was the pairing of a con-
ditioned stimulus (the white rat) with an unconditioned stimulus (fear of a loud
sudden sound) until the presence of the conditioned stimulus (the white rat) was
sufficient to elicit the unconditioned stimulus (fear).Operant Conditioning
Although classical conditioning is responsible for some human learning, Skinner
believed that most human behaviors are learned through operant conditioning. The
key to operant conditioning is the immediate reinforcement of a response. The
organism first does something and then is reinforced by the environment. Reinforce-
ment, in turn, increases the probability that the same behavior will occur again. This
conditioning is called operant conditioning because the organism operates on the
environment to produce a specific effect. Operant conditioning changes the fre-
quency of a response or the probability that a response will occur. The reinforcement
does not cause the behavior, but it increases the likelihood that it will be repeated.Shaping
With most cases of operant conditioning, the desired behavior is too complex to be
emitted without first being shaped by the environment. Shaping is a procedure in
which the experimenter or the environment first rewards gross approximations of the
behavior, then closer approximations, and finally the desired behavior itself. Through
this process of reinforcing successive approximations, the experimenter or the envi-
ronment gradually shapes the final complex set of behaviors (Skinner, 1953).
Shaping can be illustrated by the example of training a severely mentally
challenged boy to dress himself. The child’s ultimate behavior is putting on all his
own clothes. If the parent withheld reinforcement until this target behavior occurred,
the child would never successfully complete the chore. To train the boy, the parent
must break down the complex behavior of dressing into simple segments. First, the
parent gives the child a reward, say, candy, whenever the boy approximates the
behavior of positioning his left hand near the inside of the left sleeve of his shirt.
Once that behavior is sufficiently reinforced, the parent withholds reward until the
child places his hand into the proper sleeve. Then the parent rewards the child only
for putting his left arm entirely through the sleeve. Following this, the same
procedures are used with the right sleeve, the buttons, trousers, socks, and shoes.
After the child learns to dress himself completely, reinforcement need not follow
every successful trial. By this time, in fact, the ability to put on all his clothes will
probably become a reward in itself. Quite apparently, the child can reach the final
target behavior only if the parent breaks up the complex behavior into its compo-
nent parts and then reinforces successive approximations to each response.
In this example, as in all instances of operant conditioning, three conditions are
present: the antecedent (A), the behavior (B), and the consequence (C). The anteced-
ent (A) refers to the environment or setting in which the behavior takes place. In our
example, this environment would be the home or any other place the child might be
putting on clothes. The second essential condition in this example is the boy’s behavior