Alternatively, we can use punishment to eliminate unwanted behaviors.
In theory, the frequency of a behavior is reduced when it is followed by an
aversive stimulus, such as an electric shock, or the removal of a positive stimu-
lus, such as taking away toys. The effects of punishment can be demonstrated
in laboratory animals, and therapists have had some success applying this
technique in special cases. But research shows the effectiveness of punishment
is limited for several reasons.
First, punishment does not teach appropriate behaviors, it can only de-
crease the frequency of undesired ones. Rather than simply punish a child forhitting another student, it ’s better to help the child learn alternative ways to
deal with frustrating situations. Second, to be effective, punishment must be
delivered immediately and consistently. A parent needs to punish the problem
behavior as soon as possible, not “when your father gets home. ”The punish-
ment must also be fairly intense and should be administered after every in-
stance of the undesired behavior. Parents who sometimes let their children
use bad language but other times decide that to punish such talk will proba-
bly have little success in changing their children ’s vocabulary. Third, punish-
ment can have negative side effects. Although parents or therapists intend to
suppress a certain response, a child might associate other behaviors with the
punishment. A child who is punished for hitting a toy against a window may
stop playing with toys altogether. In addition, through classical conditioning,
aversive feelings that accompany the punishment may be associated with the
person doing the punishing. Children who are spanked by their parents may
associate the parent with the pain of the spanking. Another side effect is that
undesirable behaviors may be learned through modeling. Children who are
spanked may learn that physical aggression is okay as long as you are bigger
and stronger. Punishment can also create negative emotions, such as fear and
anxiety, strong enough to interfere with learning appropriate responses.
Taken together, these factors make punishment one of the least desirablechoices for behavior therapists seeking to change problem behaviors. At
most, punishment can temporarily suppress an undesirable response long en-
ough for the therapist to begin reinforcing a desired behavior.
Shaping
Suppose you are hired to work with patients in a psychiatric hospital. Your job
is to get reluctant patients more involved in some of the activities on the ward.
You start with one patient who has never participated in any of the ward activ-
ities. Your goal is to get him into daily art therapy sessions. Positive reinforce-
ment seems the right tool. Every time the patient joins in one of the voluntary
art sessions, you will reward him with coupons for free items in the hospital
store. The patient skips art therapy the first day. So no reward. He skips arttherapy the rest of the week. Still no reward. You wait 2 months, and still the
patient has not attended one of the sessions. By now, one of the problems en-
countered when using operant conditioning is apparent to you: A behaviorcan be reinforced only after it is emitted.
Does this mean operant conditioning is useless in this situation?
Fortunately, the answer is “No.” A behavior therapist working with theBasic Principles of Conditioning 349