Reinforcers and Punishers

In operant conditioning, there are four basic contingencies that can be used
to modify the frequency of occurrence of nonreflexive behavior. A contingency
refers to the relation between the situation, a behavior, and the consequence
of the behavior. A reinforcer is a consequence that makes a behavior
more likely in the future, whereas a punisher is a consequence that makes a
behavior less likely in the future. Reinforcers and punishers both come in
both positive and negative forms. A positive consequence is the presentation
of a stimulus or event as a result of the behavior, and a negative consequence
is the removal of a stimulus or event as a result of the behavior. Correctly
used, the terms “positive” and “negative” refer only to whether the
event is presented or removed, not whether the action is judged good or
bad.
A positive reinforcer is a consequence that increases the future likelihood
of the behavior that produced it. For example, if a parent were to praise a
child at dinner for eating properly with a fork, and as a result the child used
the fork properly more often, then praise would have served as a positive reinforcer.
The vast majority of scientists studying learning recommend positive
reinforcement as the best technique to promote learning. One can
attempt to increase the desired appropriate behavior through positive reinforcement,
rather than focusing on the undesired or inappropriate behavior.
If the appropriate behavior becomes more frequent, then chances are
that the inappropriate behavior will have become less frequent as well, due
to the fact that there are only so many things that a person can do at one
time.
A negative reinforcer is a consequence that increases the future likelihood
of the behavior that removed it. For example, in many cars, a buzzer or
bell sounds until the driver puts on the seatbelt. In this case, putting on the
seatbelt is negatively reinforced by the removal of the noise. Another example
of negative reinforcement occurs when a child is having a tantrum in a
grocery store until given candy. The removal of the screaming would serve
as a negative reinforcer for the parent’s behavior: In the future when the
child was screaming, the parent would probably be more likely to give the
child candy. Furthermore, the parent is providing positive reinforcement
for screaming by presenting a consequence (candy) for a behavior (screaming)
that makes the behavior more likely to occur in similar situations in the
future. This example should make clear that reinforcement is defined in
terms of the presentation or removal of an event increasing the likelihood
of a behavior in the future, not in terms of intentions or opinions. Most parents
would not consider the behavior inadvertently created and maintained
in this way to be “positive.”
Positive punishment refers to the presentation of an event that decreases
the likelihood of the behavior that produced it. For example, if a person
touches a hot stove, the pain that ensues makes it much less likely that the
person will touch the stove under those conditions in the future. In this case,
the behavior (touching the stove) produces a stimulus (pain) that makes the
behavior less frequent. Negative punishment, on the other hand, refers to
the removal of an event that decreases the likelihood of the behavior that
produced it. For example, if a birdwatcher walking through the woods
makes a loud move that causes all of the birds to fly away, then the watcher
would be less likely to move like that in the future. In this way, watchers learn
to move quietly to avoid disturbing the birds they are trying to observe.
Negative reinforcement, positive punishment, and negative punishment
all involve what is called aversive control. An aversive stimulus is anything
that an organism will attempt to escape from or try to avoid if possible.
Aversive control refers to learning produced through the use of an aversive
stimulus. For example, parents sometimes use spanking or hitting in an attempt
to teach their child not to do something, such as hitting another
child. This type of approach has been shown to have a number of undesirable
outcomes, however. One problem is that the appropriate or desired alternative
behavior is not taught. In other words, the child does not learn
what should be done instead of what was done. Another problem is that the
use of aversive stimuli can produce aggression. Humans and nonhumans
alike often respond to painful stimuli with an increased likelihood of aggression.
The aggression may or may not be directed toward the person or thing
that hurt them. Additionally, the use of aversive control can produce avoidance—
children who have been spanked or hit may try to stay away from the
person who hurt them. Furthermore, through observation, children who
have been spanked may be more likely to use physical harm to others as an
attempted solution when they encounter conflict. Indeed, corporal punishment
(the use of spanking or other physical force intended to cause a child to
experience pain, but not injury, for the purpose of correction) has been
linked to many undesirable outcomes for children, some of which extend well
into adulthood. Beginning in the 1970’s, American psychologist Murray
Straus and his colleagues investigated the impact of corporal punishment
on children. Their findings indicated that the use of corporal punishment is
associated with an increase in later antisocial behavior, a decrease in cognitive
development relative to children who are not spanked, and an increased
likelihood of spousal abuse as an adult, in addition to several other detrimental
outcomes.