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Operant Conditioning
Module 19
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Learning
Operant Conditioning Overview Skinner’s Experiments
Extending Skinner’s Understanding
Skinner’s Legacy
Contrasting Classical & Operant Conditioning
3Edward L. Thorndike ( 1874–1949)
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Thorndike’s Puzzle Box link
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Early Operant Conditioning
• E. L. Thorndike (1898)
• Puzzle boxes and cats
Scratch at bars
Push at ceiling
Dig at floorSituation:stimuliinside ofpuzzle box
Howl
Etc.
Etc.
Press lever
First Trialin Box
Scratch at bars
Push at ceiling
Dig at floorSituation:stimuliinside ofpuzzle box
Howl
Etc.
Etc.
Press lever
After ManyTrials in Box
6B. F. Skinner (1904–1990)
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B.F. Skinner and Operant Conditioning
• Classical conditioning involves an automatic response to a stimulus
• Operant conditioning involves learning how to control one’s response to elicit a reward or avoid a punishment (to press a lever for example)
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Skinner’s ExperimentsSkinner’s experiments extend Thorndike’s
thinking, especially his law of effect. This law states that rewarded behavior is likely to
occur again.
Yale University Library
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Operant Conditioning
Operant Behavior operates (acts) on environment produces consequences
Respondent Behavior occurs as an automatic response to
stimulus behavior learned through classical
conditioning
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Operant Chamber
Skinner Box chamber with a
bar or key that an animal manipulates to obtain a food or water reinforcer
contains devices to record responses
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Operant Chamber
Examples.
Walter D
awn/ Photo R
esearchers, Inc.From The Essentials of Conditioning and Learning, 3rd
Edition by Michael P. Domjan, 2005. Used with permission by Thomson Learning, Wadsworth Division
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The “Skinner Box”
• Rats placed in “Skinner boxes”
• Shaped to get closer and closer to the bar in order to receive food
• Eventually required to press the bar to receive food
• Food is a reinforcer
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Shaping
Shaping is the operant conditioning procedure in which reinforcers guide behavior towards the desired target behavior through successive approximations. link
A rat shaped to sniff mines. A manatee shaped to discriminateobjects of different shapes, colors and sizes.
Kham
is Ram
adhan/ Panapress/ Getty Im
ages
Fred Bavendam
/ Peter Arnold, Inc.
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p. 228
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p. 228
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Types of Reinforcers
Reinforcement: Any event that strengthens the
behavior it follows.
A heat lamp positively
reinforces a meerkat’s behavior
in the cold.
Reuters/ C
orbis
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Types of Reinforcement
• Positive reinforcer (+)– Adds something
rewarding following a behavior, making that behavior more likely to occur again
– Giving a dog a treat for fetching a ball is an example
• Negative reinforcer (-)– Removes something
unpleasant that was already in the environment following a behavior, making that behavior more likely to occur again
– Taking an aspirin to relieve a headache is an example
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Adapted from: The Psychology of Memory and Learning by Hintzman. © 1978 by W.H. Freeman and Company. Used with permission.
Escape Conditioning Avoidance Conditioning
Escape and Avoidance: Two types of negative reinforcement
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Learned Helplessness
• Failure to try to avoid an unpleasant stimulus because in the past it was unavoidable
• Possible model for depression in humans
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Kinds of Reinforcement and Punishment
Positive +(adding stimulus)
Negative –(removing stimulus)
Reinforcement(label afterwards to describe increase in behavior)
Punishment(label afterwards to describe decrease in behavior)
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Kinds of Reinforcement and Punishment
Positive +(adding stimulus)
Negative –(removing stimulus)
Reinforcement(label afterwards to describe increase in behavior)
Pos. Reinf.(Adding pleasant
consequence)
Punishment(label afterwards to describe decrease in behavior)
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Kinds of Reinforcement and Punishment
Positive +(adding stimulus)
Negative –(removing stimulus)
Reinforcement(label afterwards to describe increase in behavior)
Pos. Reinf.(Adding pleasant
consequence)
Neg. Reinf.(Removing Aversive
Stimuli)
Punishment(label afterwards to describe decrease in behavior)
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Kinds of Reinforcement and Punishment
Positive +(adding stimulus)
Negative –(removing stimulus)
Reinforcement(label afterwards to describe increase in behavior)
Pos. Reinf.(Adding pleasant
consequence)
Neg. Reinf.(Removing Aversive
Stimuli)
Punishment(label afterwards to describe decrease in behavior)
Pos. Pun.(Adding aversive stimuli)
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Kinds of Reinforcement and Punishment
Positive +(adding stimulus)
Negative –(removing stimulus)
Reinforcement(label afterwards to describe increase in behavior)
Pos. Reinf.(Adding pleasant
consequence)
Neg. Reinf.(Removing Aversive
Stimuli)
Punishment(label afterwards to describe decrease in behavior)
Pos. Pun.(Adding aversive stimuli)
Neg. Pun.(Removing pleasant
stimuli)
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Examples
Link 1
Link 2
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Negative Reinforcement and Punishment
Negative reinforcement: Removing an unpleasant stimulus
Punishment
1. Unpleasant stimulus
2. Removal of unpleasant stimulus
=
=
1. Introducing an unpleasant stimulus
2. Withholding a pleasant stimulus
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Figure 6.18 Positive reinforcement versus negative reinforcement
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Figure 6.20 Comparison of negative reinforcement and punishment
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IMPORTANT!!• Negative reinforcement is NOT punishment.
• Negative reinforcement is the REMOVAL of unpleasant stimulus when target behavior is observed (a positive consequence of behavior – increases behavior)
• Punishment is the introduction of an aversive (unpleasant) stimulus or removal of a pleasant stimulus as a consequence of behavior – ( a negative consequence of behavior - decreases behavior.
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Punishment
An aversive event that decreases the behavior it follows.
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1. Primary Reinforcer: An innately reinforcing stimulus like food or drink. (satisfies a biological need
2. Conditioned (secondary) Reinforcer: A learned reinforcer that gets its reinforcing power through association with the primary reinforcer.
Primary & Secondary Reinforcers
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1. Immediate Reinforcer: A reinforcer that occurs instantly after a behavior. A rat gets a food pellet for a bar press.
2. Delayed Reinforcer: A reinforcer that is delayed in time for a certain behavior. A paycheck that comes at the end of a week.
Immediate & Delayed Reinforcers
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Reinforcement Schedules
1. Continuous Reinforcement: Reinforces the desired response each time it occurs.
2. Partial (intermittent) Reinforcement: Reinforces a response only part of the time. Though this results in slower acquisition in the beginning, it shows greater resistance to extinction later on.
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Schedules of Reinforcement
• Partial reinforcement lies between continuous reinforcement and extinction
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Schedules of Reinforcement Fixed Ratio (FR)
reinforces a response only after a specified number of responses
faster you respond the more rewards you get
different ratios very high rate of
responding like piecework pay
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Schedules of Reinforcement Variable Ratio (VR)
reinforces a response after an unpredictable number of responses
like gambling, fishing very hard to
extinguish because of unpredictability
Skinner link 3:58
SLOT machines show SLOwesT extinction.
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Schedules of Reinforcement Fixed Interval (FI)
reinforces a response only after a specified (fixed) time has elapsed
response occurs more frequently as the anticipated time for reward draws near
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Schedules of Reinforcement Variable Interval
(VI) reinforces a
response at unpredictable time intervals
produces slow steady responding
like pop quiz
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Variable Interval(VI)
Variable Ratio(VR)
Fixed Interval(FI)
Fixed Ratio(FR)
Based on Number of necessary responses
Based on Time that must
first pass
Predictable
Unpredictable (“On the
Average”)
Intermittent Reinforcement Schedules Summary
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Schedules of Reinforcement
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• You do not have to write down the following examples.
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FI, VI, FR, or VR?1. When I bake cookies, I can only put one set in at a
time, so after 10 minutes my first set of cookies is done. After another ten minutes, my second set of cookies is done. I get to eat a cookie after each set is done baking.
2. After every 10 math problems that I complete, I allow myself a 5 minute break.
3. I look over my notes every night because I never know how much time will go by before my next pop quiz.
4. When hunting season comes around, sometimes I’ll spend all day sitting in the woods waiting to get a shot at a big buck. It’s worth it though when I get a nice 10 point.
5. Today in Psychology class we were talking about Schedules of Reinforcement and everyone was eagerly raising their hands and participating. Miranda raised her hand a couple of times and was eventually called on.
1. FI
2. FR
3. VI
4. VI
5. VR
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FI, VI, FR, or VR?6. Madison spanks her son if she has to ask him three
times to clean up his room.7. Emily has a spelling test every Friday. She usually
does well and gets a star sticker.8. Steve’s a big gambling man. He plays the slot
machines all day hoping for a big win.9. Snakes get hungry at certain times of the day. They
might watch any number of prey go by before they decide to strike.
10. Mr. Bertani receives a salary paycheck every 2 weeks. (Miss Suter doesn’t ).
11. Christina works at a tanning salon. For every 2 bottles of lotion she sells, she gets 1 dollar in commission.
12. Mike is trying to study for his upcoming Psychology quiz. He reads five pages, then takes a break. He resumes reading and takes another break after he has completed 5 more pages.
6. FR7. FI
8. VR
9. VI
10. FI
11. FR
12. FR
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FI, VI, FR, or VR?13. Megan is fundraising to try to raise money so she can
go on the annual band trip. She goes door to door in her neighborhood trying to sell popcorn tins. She eventually sells some.
14. Kylie is a business girl who works in the big city. Her boss is busy, so he only checks her work periodically.
15. Mark is a lawyer who owns his own practice. His customers makes payments at irregular times.
16. Jessica is a dental assistant and gets a raise every year at the same time and never in between.
17. Andrew works at a GM factory and is in charge of attaching 3 parts. After he gets his parts attached, he gets some free time before the next car moves down the line.
18. Brittany is a telemarketer trying to sell life insurance. After so many calls, someone will eventually buy.
13. VR
14. VI
15. VI
16. FI
17. FR
18. VR
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Updating Skinner’s Understanding
• Skinner’s emphasis on external control of behavior made him an influential, but controversial figure.
• Many psychologists criticized Skinner for underestimating the importance of cognitive and biological constraints.
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Cognitive Approach
This approach emphasizes abstract and subtle learning that could not be achieved through conditioning or social learning alone.
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Cognition & Operant Conditioning
Evidence of cognitive processes during operant learning comes from rats during a maze
exploration in which they navigate the maze without an obvious reward. Rats seem to
develop cognitive maps (E.C. Tolman), or mental representations, of the layout of the maze
(environment).
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Latent Learning
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Intrinsic Motivation
Intrinsic Motivation: The desire to perform a behavior for its own sake.
Extrinsic Motivation: The desire to perform a behavior due to promised rewards or threats of punishments.
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Biological Predisposition
Biological constraints predispose
organisms to learn associations that are naturally adaptive.
Marian Breland Bailey
Ph
oto
: Bob
Baile
y
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Skinner’s Legacy
Skinner argued that behaviors were shaped by external influences instead of inner thoughts and
feelings. Critics argued that Skinner dehumanized people by neglecting their free will.
Falk/ Photo Researchers, Inc.
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Applications of Operant Conditioning
Skinner introduced the concept of teaching machines that shape learning in small steps and provide reinforcements
for correct rewards.
In School
LW
A-JD
L/ C
orbis
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Applications of Operant Conditioning
Reinforcers affect productivity. Many companies now allow employees to share
profits and participate in company ownership.
At work
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Applications of Operant Conditioning
At Home
In children, reinforcing good behavior increases the occurrence of these behaviors.
Ignoring unwanted behaviors decreases their occurrence.
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EXPLORING PSYCHOLOGY(7th Edition in Modules)
David MyersPowerPoint Slides
Aneeq AhmadHenderson State
University, Amy Jones, Bernstein, Schallhorn with
Garber edits
Worth Publishers, © 2008
