Principles of BehaviorSixth Edition

Richard W. MalottWestern Michigan University

Power Point by Nikki Hoffmeister

Chapter 8

Shaping

Example

• Andrew entered Big State Hospital when he was 21

• From the day he entered, he didn’t say a word – 19 years of silence

• He attended Dawn’s group therapy session with patients who did speak

• In one session Dawn accidentally dropped a stick of chewing gum from her purse

• Andrew showed interest in the gum

Andrew

• In the next group session, Dawn held the gum in front of Andrew’s face and waited until he looked at it

• Then she immediately gave him the gum• After 2 weeks, he reliably looked at the

gum when she held it in front of his face

Next Step

• Dawn waited until Andrew moved his lips slightly before giving him the gum

• After he was doing this reliably, she waited until he made a sound before giving him the gum

Before

Andrew has no gum

BehaviorInitial:

Andrew moves his lips

After

Andrew has gum

Differential Reinforcement

Before:

Andrew has no gum

After:

Andrew has no gum

Behavior

Intermediate:

Andrew moves his lips

Behavior

Intermediate:

Andrew makes croaking sound

After:

Andrew has gum

Terminal Behavior

• Then Dawn prompted him to say “gum gum”

• His croaking sound faintly resembled “gum”

• Dawn immediately reinforced this response

• She then reinforced closer and closer approximations to the word “gum”

Differential Reinforcement

Before:

Andrew has no gum

After:

Andrew has no gum

Behavior

Intermediate:

Andrew makes croaking sound

Behavior

Terminal:

Andrew says gum

After:

Andrew has gum

Results

• Andrew clearly said, “Gum, please,” after 6 weeks of this intervention.

• After that day he would answer any question Dawn asked.

• He also chatted with his nurse outside of therapy sessions.

Analysis

• Because he didn’t talk, everyone assumed he couldn’t.

• So they interpreted his gestures and signs.• When 2 responses produce the same

reinforcers, we tend to do the one needing the least effort.

• But the contingencies changed when Dawn required more and more effortful vocal and verbal behavior before she delivered the reinforcer.

Shaping with Reinforcement

Operant Level:• The frequency of responding before

reinforcement.

Terminal Behavior:• Behavior not occurring in the repertoire or

not occurring at the desired frequency; the goal of the intervention.

What is Initial Behavior?

Initial Behavior:• Behavior that resembles the terminal

behavior • along some meaningful dimension • and occurs at least with a minimal

frequency.

What is Intermediate Behavior?

Intermediate Behavior:• Behavior that more closely approximates

the terminal behavior.

So What is Shaping with Reinforcement?

Shaping with Reinforcement:• The differential reinforcement of only the

behavior • that more and more closely resembles the

terminal behavior.

When do you use shaping?

• When you want to bring about new responses.• Reinforce the initial behavior until it occurs

frequently.• Then abandon that response.• Select and differentially reinforce another

response that approximates the terminal behavior.

• Continue until the terminal behavior occurs, and reinforce it until it occurs frequently.

Shaping Reinforcement

Before:Andrew has no gum

After:

Andrew has no gum

BehaviorInitial:

Not applicableIntermediate:

Moves lips onlyTerminal:

Says words unclearly

BehaviorInitial:

Andrew moves lipsIntermediate:

Makes croaking soundTerminal:

Says words clearly

After:

Andrew has gum

Example

• Dicky, the autistic boy, needed glasses.• The glasses were aversive for Dicky, and

he would not wear them.• Mont Wolf and his team of behavior

analysts spent 2-3 20-minute sessions with Dicky in his room.

Procedure

• They reinforced Dicky’s carrying his glasses,

• bringing them closer and closer toward his face,

• and actually putting them on.• A gradual shaping process.

Shaping Reinforcement

Before:Dicky has no candy or fruit

After:

Dicky has no candy or fruit

BehaviorInitial:

Not applicableIntermediate:

Only carries glassesTerminal:

Glasses only near face

BehaviorInitial:

Carries glassesIntermediate:

Glasses near faceTerminal:

Puts on glasses

After:

Dicky has fruit or candy

Is wearing glasses a behavior?

• No.• It fails the dead man test.• So we talk about putting the glasses on or

taking them off.

Results

• After 30 minutes of shaping, Dicky was putting on the glasses properly and looking through the lenses at various toys.

• Soon he put his glasses on any time they requested.

Example• 13-year old Melanie was aphonic.

– She spoke in a low, raspy whisper• Behavior analysts used praise to shape the

loudness of her vocal responses.• First they shaped breathing, then humming, then

saying consonants, then reading, and finally conversing.

• They helped her speak loudly and clearly.• During a 2-year follow up they realized her vocal

responses were still loud and clear.

Shaping with Reinforcement

Before:

Melanie gets no praise

After:

Melanie gets no praise

BehaviorInitial:

Converses very lightlyIntermediate:

Converses lightlyTerminal:

Converses Moderately

BehaviorInitial:

Converses lightlyIntermediate:

Converses moderatelyTerminal:

Converses loudly

After:

Melanie gets praise

What is Shaping with Punishment?

Shaping with Punishment:• The differential punishment of all behavior

except that which more and more closely resembles the terminal behavior.

Example

• Juke taught himself how to do a headstand.

• He started with his legs over his head, leaning against a wall.

• Once he could hold his feet against the wall for 1 minute, he raised the criterion.

• He tried to stand on his head without touching the wall; but he fell.

• But he got better and better.

What was the contingency?

• Both shaping with reinforcement,– Right moves caused him to feel good about himself

• and shaping with punishment.– Wrong moves caused him to fall or almost fall

• As with all punishment contingencies, the general response class needs some history of reinforcement.– Some reinforcement needed to maintain Juke’s

standing on his head or the punishment of falling would suppress all efforts

Example

• Little Rod was in his crib• His favorite toy, a rattle, is in the far corner• He squirms toward it and finally scores• During the next few weeks he gets better

at squirming• The squirm evolved into a crawl• His crawl evolved into a toddle, and then a

walk

Differential Reinforcement

Before:Rod has no rattle in his hand

After:

Rod has no rattle in his hand

Behavior:

Rod does a weak squirm

Behavior:

Rod squirms forcefully

After:

Rod has a rattle in his hand

Shaping Along the Force Dimension

Before:Rod has no rattle in his hand

AfterInitial:

No rattleIntermediate:

Rattle in 10 secondsTerminal:

Rattle in 6 seconds

BehaviorInitial:

Weak forceIntermediate:

ForcefulTerminal:

Very forceful

BehaviorInitial:

ForcefulIntermediate:

Very forcefulTerminal:

Super forceful

AfterInitial:

Rattle in 10 secondsIntermediate:

Rattle in 6 secondsTerminal:

Rattle in 4 seconds

Natural Shaping

• The natural environment differentially reinforced squirming

• Force was the response dimension• Rod got the reinforcing rattle only if he

squirmed with sufficient force• The more forcefully Rod squirmed, the

more quickly he got to the rattle• Getting to the rattle quickly is more

reinforcing than getting it slowly

Shaping Along the Topography Dimension

Before:Rod has no rattle in his hand

AfterInitial:

Rattle in 10 secondsIntermediate:

Rattle in 4 secondsTerminal:

Rattle in 2 seconds

BehaviorInitial:

Weak squirmIntermediate:

Rod squirmsTerminal:

Rod toddles

BehaviorInitial:

Rod squirmsIntermediate:

Rod toddlesTerminal:

Rod runs

AfterInitial:

Rattle in 4 secondsIntermediate:

Rattle in 2 secondsTerminal:

Rattle in 1 seconds

What is Fixed-Outcome Shaping?

Fixed-Outcome Shaping:• Shaping that involves • no change in the value of • the reinforcer, • or aversive condition, • as the performance criterion more and

more closely resembles the terminal behavior.

What is Variable-Outcome Shaping?

Variable-Outcome Shaping:• Shaping that involves a change in the

value of • the reinforcer, • or aversive condition, • as performance more and more closely

resembles the • terminal behavior.

Example: Fixed-Outcome Shaping