lecture 6 decreasing the frequency of behavior – extinction and differential reinforcement...

Lecture6 decreasing THE FREQUENCY OF BEHAVIOR –

Extinction and Differential Reinforcement

Behavior Analysis

Review

Most behavior problems fall into one of two categories Behavior that doesn’t occur enough Behavior that occurs too much

So far we have addressed how to increase the frequency of behavior Reinforcement Prompting, Fading, Shaping and Chaining are procedures used with

reinforcement to increase behavior rate

Now we will learn how to decrease the frequency of behavior

In other words, in certain behavior problems the target behavior occurs too much, we need to learn how to reduce the amount of times the target behavior occurs

Review

Can we think of any examples? Parents often complain that their kids

Talk on the phone too much Eat too much Go out too much Complain too much Cost too much

Teachers may complain that their students Walk around the room too much Fight too much Cry too much Call out answers too much

With these problems the task is not to strengthen behavior, but to weaken it!

Today's lesson

Today we discuss two procedures used for reducing the frequency of behavior Extinction Differential reinforcement

Extinction

Operant behavior is maintained by its consequences.

Therefore, preventing the consequences that maintain a behavior should weaken it. In other words, problematic behavior is likely to pay off

because the consequences following the behavior are reinforcing

Therefore if we stop the reinforcing consequences then we would expect the behavior to occur less often

This is extinction

Extinction: withholding the reinforcers that maintain a target behavior

Extinction

Behaviorists often talk about a behavior as having been‘extinguished’

When they say this they mean that the frequency of the behavior has been reduced by the extinction procedure

Note: extinction does not mean that the behavior no longer occurs or is ‘extinct

The effect of extinction is to reduce the frequency of the target behavior

Example

Nellie taps her fingers during work 5 or 6 times day.One day a co worker asks Nellie if she is ok. This

leads to a conversation about Nellie’s feelings that Nellie finds reinforcing.

The finger tapping therefore increase to around 30-40 times per day.

Then the co-worker moves to a different job.The reinforcer is no longer available. So the finger tapping reduces to pre intervention

rates: 5 or 6 times per dayLets look at some case studies:

Bill, the crier

When young children cry after falling over, crying is to be expected.

However sometimes young children cry for no reason, which may annoy others and interfere with their own healthy development.

Bill was one such child

Bill, the crier

Bill was a normal healthy boy He had above average intelligence and good social

skills However Bill cried more than any other child in

school, around 5 to 10 times per morning Near enough anything was enough to make Bill cry,

and when he cried, the whole school knew about it Bill would only stop crying after the teacher

comforted him for several minutes Teachers began to wonder if Bill cried because of the

attention he received when he cried

Hart et al (1964)

Betty Hart agreed that attention might be the reinforcer and decided to see if extinction might help

To begin with, teachers measured each time Bill cried with a pocket counter The target behavior was defined as crying that last for 5

seconds and could be heard from 50 foot away

At the end of each day someone recorded the total number of crying episodes on a cumulative graph The teachers did this for 10 days to get a baseline, there

was no effort to modify Bills behavior

Hart et al (1964)

After 10 days, treatment consisted of putting crying on extinction This meant that when Bill cried teachers were to look his

way to make sure that Bill was not hurt, after which they were to pay no attention to him

Each time Bill had an unpleasant experience and did not cry, then the teacher was to give Bill praise and attention

The results indicated that the frequency of crying fell dramatically, so that after 5 days of extinction Bill was crying only two times per day

In order to make sure that it was the intervention that powered the change, the researchers employed an ABAB design. The results held up.

Lets draw the graph!

Extinction

Extinction is basically a very simple procedure: prevent the target behavior from occurring by withholding consequences and it declines

But, as with reinforcement, it can be difficult to successfully apply In fact it can be pretty easy to make a mess of things

There are some rules for extinction that will help you Define the target behavior Identify the reinforcers that maintain the target behavior Withhold all reinforcement of the target behavior Monitor the results

Define the target behavior

Defining the target behavior is just as important when it comes to decreasing the rate of behavior as it is when attempting to increase the rate of behavior

You must always have a very clear and operational idea of what the target behavior is

Identify the reinforcers that maintain the target behavior

If operant behavior occurs on a regular basis, you can safely assume that it is being reinforced.

To put the behavior on extinction, you have to identify the reinforcer, so that you know what to withhold.

However this is easier said than done For example, it is unlikely that a child will say ‘I cry

because in the past crying has produced adult attention’.

Therefore in order to find the reinforcer you have to work it out by observing the behavior and its consequences for a time

A number of consequences may follow a behavior, it is very important to pinpoint the consequence that is functioning as a reinforcer

Withhold all reinforcement of the target behavior

Extinction involves the target behavior not being reinforced

However doing so can sometimes be difficultFor example, it is difficult to withhold

attention if Bill has fallen over and hurt himself


A more serious example occurs when reinforcement becomes too difficult to control. For example, imagine that every time Jonny shouts out in class,

his fellow students laugh. Laughing is the reinforcer here. To put this into extinction you would have to stop the kids laughing at Jonny’s remarks every time he shouts out. This would be very difficult.

Notice the words ‘every time’ there. Extinction only works if the reinforcer is with held every time the behavior occurs.

Because occasional reinforcement can maintain behavior at very high rates and can even make the behavior more difficult to eliminate


This phenomenon is called

Partial reinforcement effect: increased resistance to extinction following intermittent

reinforcement.

This means that it is not a good idea to start extinction unless you can be sure that you can withhold all reinforcement of the target behavior A good example of PRE is gambling behavior

Monitor the results

The only way to make sure that extinction is working is to monitor the results.

For example if you have gone with the wrong consequence that doesn‘t actually function as a reinforcer then the only way to know is to monitor the results

Problems with extinction – uncontrolled reinforcement

The problem, as previously mentioned, is that the target behavior may produce reinforcement from a number of sources. And those sources may be difficult to control

Another problem occurs when the activity is reinforcing in itself. This makes extinction impossible. For example, how do you extinguish a behavior when

you can’t reduce the level of reinforcement?

Problems with extinction –slowness

Sometimes extinction can be very slowThis is a problem because the longer it take for a

behavior to extinguish, the more likely people will give up.

Also, imagine that the target behavior is severe, like head banging. By the time the extinction procedure has worked the kid could be blind!

It is therefore hard to justify using extinction when the behavior is harmful

Another example is destruction of property – it is hard to use extinction when things are being destroyed!

Problems with extinction – side effects

Extinction can produce some dramatic side effects that can be problematic

The long term effect of extinction is a steady and pronounced reduction in the frequency of a target behavior

But the immediate effect of putting a behavior on extinction is a sudden increase the target behavior For example, Bill might start crying a huge amount of times

before the reductions in target behavior began

This is called an extinction burstExtinction burst: a sharp increase in the frequency of

the behavior on extinction


Extinction bursts can be a problem because you might easily conclude that the extinction procedure wasn’t working, and give up.

It is therefore important to understand, and to inform every party that the behavior may get worse before it gets better

Otherwise people are likely to go back to reinforcing the behavior, which may make the behavior occur at a higher rate


There are two further side effects of extinction: Resurgence Spontaneous recovery

Resurgence occurs when behavior that used to produce reinforcement in the past reappears

Resurgence: the reappearance, during extinction, of previously effective behavior.


Imagine little harry learns at home that throwing things across the room gets him what he wants.

Then he learns in school that there are more socially acceptable ways to get things i.e. be polite.

Harry grows up and gets married, but his wife annoys him but leaving shoes around the place.

Harry politely asks her to stop, but one day she forgets (being polite is put into extinction).

The next time his wife leaves shoes around the place Harry yells and throw things across the room.

Here a behavior which used to produce reinforcement has reappeared


Resurgence can be compared to Freud’s idea of regression. Freud suggested that immature behavior may reappear later in life.

From a behaviorist perspective, any behavior that once produced reinforcement may reappear if another way of obtaining reinforcement is put on extinction

Behaviorists therefore have to be very careful not to reinforce unacceptable behavior that has resurged, or it will strengthen


Sometimes after the successful completion of an extinction procedure, the behavior suddenly reappears without warning, this is called spontaneous recovery

Spontaneous recovery: the reappearance of the target behavior following its extinction

Spontaneous recovery is not a problem, as long as the behavior is not reinforced when it reappears.


The difference between resurgence and spontaneous recovery is that in spontaneous recovery the behavior that reappears is the behavior on extinction

Whereas with resurgence the behavior that reappears is some other behavior that has produced reinforcement in the past

As you can see there are problems with extinction. However these problems can often be overcome is they are used with other procedures. One of these is called differential reinforcement.

Differential Reinforcement

Differential Reinforcement is an umbrella term for several procedures in which the rate of target behavior is changed by the combined used of extinction and reinforcement

Differential Reinforcement: any procedure that combines reinforcement and extinction to change

the frequency of a target behavior.

Note: you can use DR to increase of decrease the target behavior, today we concentrate on the latter

Kinds of Differential Reinforcement

Although it may be difficult to understand how reinforcement could reduce the frequency of a behavior, some examples of the kinds of DR will help clarify the situation

Lets start simple, we are dealing with problems where the behavior occurs too often.

If we want the behavior to occur less often, then it can be a good idea to provide reinforcement for the behavior when it occurs less often. This is called differential reinforcement of low rate (DRL)

DRL

DRL: the procedure of reinforcing the target behavior when it occurs at a low rate.

‘But how can we reinforce behavior without making it occur less often?’

It sounds crazy but the key difference is that were not just reinforcing the behavior, were reinforcing the behavior only when it occurs at a low rate.

Lets think of an example

DRL

Imagine we have a child (Mike) who eats too fast We want him to eat more slowly

This could mean that he currently puts food in his mouth ten times a minute

Using DRL we would choose a lower number, say 4 lots of food per minute, and reinforce that behavior.

Therefore we are reinforcing the act of eating slowly

Differential Reinforcement of Alternate Behavior (DRA)

The idea behind DRA is to put the target behavior on extinction, whilst reinforcing some other behavior.

DRA: the procedure of reinforcing an alternate behavior instead of the target behavior

In DRA reinforcers that were available for the target behavior become contingent of some more acceptable alternate behavior.

For example, whereas attention used to be given to a child for screaming, now attention is not given for screaming, but is given for playing quietly with toys

Differential Reinforcement of Incompatible behavior (DRI)

Imagine I asked you to sit down and walk across the room at the same time? Impossible right?

Well that forms the basis for DRIOne way to reduce the frequency of an

unwanted behavior is to reinforce other behavior that is incompatible with that behaviorDRI: the procedure of reinforcing a behavior that is incompatible with the target behavior

Differential Reinforcement of Incompatible behavior (DRI)

For example, the chief reason why kids get out of their seat in school is the attention that they get from the teacher Some teachers can reduce the frequency of such behavior by ignoring it:

putting it on extinction

However this may take some time, especially if the students have received attention for wandering for some time. DRI speeds up this process and avoids the negative side effects of extinction

This is because DRI creates a situation where the child can still get reinforcement, but they are getting it for a behavior that is incompatible with the target behavior. Now students get attention for being in their seats

DRI and DRA are very similar. The difference being that in DRA the ‘other’ behavior being reinforced is not necessarily incompatible with the target behavior

Rules for using differential reinforcement

Define the target behaviorPut the undesirable target behavior on

extinctionReinforce the desirable target behaviorMonitor the results

Define the target behavior

With DR, there are generally two target behaviors. You're trying to reduce the frequency of one behavior and increase the frequency of another.

In some cases the target behaviors are different rates of the same activity e.g. eating fast versus eating slow

Put the undesirable target behavior on extinction

Here you need to identify the reinforcers that are maintaining the problematic behavior.

When you have done this you must prevent those reinforcers from following the unwanted behavior

Reinforce the desirable target behavior

While you have the undesirable behavior on extinction, you reinforce the desirable behavior

So you put the behavior you want to weaken on extinction, and you reinforce the behavior you want to strengthen

Monitor the results

You need to make sure that your intervention is producing the desired results.

For example your reinforcer may be wrong, or bootleg reinforcement may be causing problems.

You will only know these things if you measure what's happening.

Flash card

Extinction withholding the reinforcers that maintain a target behavior

Partial reinforcement effect increased resistance to extinction following intermittent

reinforcement

Extinction burst a sharp increase in the frequency of the behavior on extinction

Resurgence reappearance during extinction of previously effective behavior

Spontaneous recovery reappearance of target behavior following its extinction

Flash card

Differential Reinforcement procedure that combines extinction and reinforcement

to change the frequency of a target behavior

DRL procedure of reinforcing the target behavior only when

it occurs at a low rate

DRA procedure of reinforcing an alternative behavior instead

of the target behavior

DRI procedure of reinforcing a behavior that is incompatible

with the target behavior

Flash card

DRL stands for: Differential reinforcement of low rates

DRA stands for: Differential reinforcement of alternative behavior

DRI stands for: Differential reinforcement of incompatible behavior

lecture 6 decreasing the frequency of behavior – extinction and differential reinforcement...

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