Thus, classical or respondent conditioning is a
purely behavioral type of learning. Animals or people
conditioned in this manner do not consciously learn
the associations between the stimuli and the re-
sponses. Instead, because the pairings occur repeat-
edly, the conditioned stimulus elicits the conditioned
response unconsciously. In some instances, however,
these responses are not automatic; instead, certain
outcomes will induce the animals or humans to repeat
the behavior while other outcomes cause them not to
repeat the behavior.
Operant or Instrumental Conditioning
Operant conditioning, also known as instrumen-
tal conditioning, is based on the consequences that
follow an organism’s behavior. Behaviors that are fol-
lowed by a reward, or reinforcement, usually increase
in frequency, while behaviors that are followed by
punishments usually decrease in frequency. The con-
text in which the rewards or punishments are re-
ceived has an effect on how the association between
the behavior and the consequence following the be-
havior are learned. In addition, how often reinforce-
ment follows any particular behavior has an effect on
how well the association is learned.
The Effect of Reward or Punishment on
Behavior
American psychologist Edward Thorndike’s Law
of Effect states that depending on the outcome, some
responses get weakened while other responses get
strengthened, and this process eventually leads to
learning. Thorndike noted that when an animal was
rewarded for a certain behavior, that behavior be-
came progressively more frequent while behaviors
that did not elicit a reward weakened and became
sporadic, finally disappearing altogether. In other
words, unlike classical conditioning, what follows a
behavior or response is what is primarily important.
In his mid-twentieth-century experiments with
rats and pigeons, American psychologist B. F. Skin-
ner found that animals use their behaviors to shape
their environment, acting on the environment in
order to bring about a reward or to avoid a punish-
ment. Skinner called this type of learning operant or
instrumental conditioning. A reward or reinforce-
ment is an outcome that increases the likelihood that
an animal will repeat the behavior. There are two
types of reinforcement: positive and negative. Posi-
tive reinforcement is something given that increases
the chance that the animal or person will repeat the
behavior; for example, smiling or praise whenever a
student raises her hand is a form of positive reinforce-
ment if it results in increased hand-raising. Negative
reinforcement occurs when something is taken away;
stopping an electric shock to elicit a behavior from a
rat is an example, because whatever behavior the rat
exhibited to terminate the shock will increase.
A punishment, on the other hand, is an outcome
for which the likelihood of a future behavior de-
creases. For example, spanking or slapping a child is
an example of punishment, as is grounding, because
all three can be expected to reduce the occurrence of
the behavior that preceded them.
There are a number of ways in which someone
can manipulate an animal’s or a person’s behavior
using operant or instrumental conditioning. One of
these methods is called shaping and involves reinforc-
ing behaviors as they approach the desired goal. Sup-
pose a person wants to train a dog to jump through
a hoop. He would first reward the dog for turning to-
ward the hoop, then perhaps for approaching the
hoop. Eventually he might reward the dog only for
walking through the hoop if it is low to the ground.
Finally, he would raise the hoop off the ground and
reward the dog only for jumping through the hoop.The Role of Context
Context is extremely important for operant con-
ditioning to occur. Both animals and people must
learn that certain behaviors are appropriate in some
contexts but not in others. For instance, a young child
might learn that it is acceptable to scribble with a cray-
on on paper but not on the wall. Similarly, Skinner
found that animals can discriminate between differ-
ent stimuli in order to receive a reward. A pigeon can
discriminate between two different colored lights and
thereby learn that if it pecks a lever when a green light
is on it will receive food, but if it pecks when the red
light is on it will not receive food.
What is more, animals can discriminate between
different behaviors elicited by different contexts. For
example, a rat can learn that turning around clock-
wise in its cage will result in getting food but that in
a different cage turning counterclockwise will bring a
reward. Animals will also generalize to other stimuli,
performing the desired behavior when a slightly dif-
ferent stimulus occurs. For instance, a pigeon that
knows that pecking a lever when a green light is on
will bring food might also peck the lever when a dif-
ferent-colored light is on. Both generalization and
discrimination help animals and people learn which
behaviors are appropriate in which contexts.Reinforcement Schedules
The rate of reinforcement can also affect the fre-
quency of the desired response. Delaying reinforce-
ment slows learning down, although research shows
that humans can learn from delayed reinforcements,
and that it is often difficult to forfeit immediately pos-
itive outcomes in order to avoid adverse ones later.LEARNING 237