copyright © allyn and bacon 2006 1 chapter 6 learning this multimedia product and its contents are...

Copyright © Allyn and Bacon 2006

11

Chapter 6Chapter 6

LearningLearning

This multimedia product and its contents are protected under copyright law. The following are prohibited by law: any public performance or display, including transmission of any image over a network; preparation of any derivative work, including the extraction, in whole or part, of any images; any rental, lease, or lending of the program. ISBN: 0-205-42428-7

22Copyright © Allyn and Bacon 2006

LearningLearning

Learning – A process through which experience produces lasting change in behavior or mental processes

Behavioral learning – Forms of learning that can be described in terms of stimuli and responses


LearningLearning

Three types of Learning

• Classical Conditioning

• Operant or Instrumental Learning

• Cognitive or Social Learning


Classical conditioning is a basic form of learning in which

a stimulus that produces an innate reflex becomes

associated with a previously neutral stimulus, which then acquires the power to elicit

essentially the same response

What Sort of Learning Does What Sort of Learning Does Classical Conditioning Explain?Classical Conditioning Explain?


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DemonstrationDemonstration


The Essentials of Classical The Essentials of Classical ConditioningConditioning

Neutral stimulus – Any stimulus that produces no conditioned response prior to learning

Acquisition – Initial learning stage in classical conditioning; conditioned response becomes elicited by the conditioned stimulus



Unconditioned Unconditioned response (UCR)response (UCR)

Unconditioned Unconditioned stimulus (UCS)stimulus (UCS)

Conditioned Conditioned response (CR)response (CR)

Conditioned Conditioned stimulus (CS)stimulus (CS)



Unconditioned response (UCR)

Unconditioned Unconditioned stimulus (UCS)stimulus (UCS)

Conditioned response (CR)

Conditioned stimulus (CS)

The stimulus that elicits an unconditioned response



Unconditioned Unconditioned response (UCR)response (UCR)

Unconditioned stimulus (UCS)



The response elicited by an unconditioned stimulus without prior learning






Conditioned Conditioned stimulus (CS)stimulus (CS)

A previously neutral stimulus that comes to elicit the conditioned response





Conditioned Conditioned response (CR)response (CR)


A response elicited by a previously neutral stimulus that has become associated with the unconditioned stimulus


Classical ConditioningClassical ConditioningPrior to conditioning

Conditioning

After conditioning

Neutral stimulus(tone)

(Orientation to soundbut no response)

Unconditioned stimulus(food powder in mouth)

Unconditioned response(salivation)

Neutral stimulusCS (tone)

Unconditioned stimulus(food powder)

+Conditioned response

(salivation)

Conditioned stimulus(tone)

Conditioned response(salivation)


Classical ConditioningClassical Conditioning

Extinction – Weakening of a conditioned association in the absence of an unconditioned stimulus or reinforcer

Spontaneous recovery –Reappearance of an extinguished conditioned response after a time delay


Acquisition, Extinction, and Acquisition, Extinction, and Spontaneous RecoverySpontaneous Recovery

(1)Acquisition(CS + UCS)

(3)Spontaneous Recovery(CS alone)

Res

t per

iod(2)

Extinction(CS alone)

(Time)

Trials

Str

engt

h of

the

CR

(Wea

k)(S

tron

g)


Classical Conditioning:Classical Conditioning:Generalization and DiscriminationGeneralization and Discrimination

Stimulus generalization involves giving a conditioned response to stimuli that are similar to the CS

Stimulus discrimination involves responding to one stimulus butnot to stimuli that are similar

Confusing stimuli may cause experimental neurosis


Applications of Classical ConditioningApplications of Classical Conditioning

Taste-aversion learning – Biological tendency in which an organism learns to avoid food with a certain taste after a single experience, if eating it is followed by illness


One Final Thought on PavlovOne Final Thought on Pavlov

Why are some stimuli-consequence combinations readily learned while other combinations are highly resistant to learning?

What any organism can or cannot learn in a given setting is due in part to its evolutionary history


How Do We LearnHow Do We LearnNew Behaviors byNew Behaviors by

Operant Conditioning?Operant Conditioning?

In operant conditioning, the consequences of behavior,

such as rewards and punishments, influence the

chance that our behavior will occur again


Skinner’s Radical BehaviorismSkinner’s Radical Behaviorism

B.F. Skinner believed that the most powerful influences on behavior are its consequences


How Do We LearnHow Do We LearnNew Behaviors byNew Behaviors by

Operant Conditioning?Operant Conditioning?

Trial-and-error learning – Learner gradually discovers the correct response by attempting many behaviors and noting which ones produce the desired consequences


Reinforcement vs PunishmentReinforcement vs Punishment

• Reinforcement

• Anything that increases a behavior or response

• Punishment

• Anything that decreases or stops a behavior/response


Types of ConsequencesTypes of Consequences

Positive

(Add)

Negative

(Remove)

Reinforcement Apply reward to increase behavior

(e.g., Getting A’s for studying hard)

Remove aversive stimulus to

increase behavior

(e.g., Advil relieves headache)

Punishment Apply negative consequence to

decrease behavior

(e.g., Spanking)

Remove desirable stimulus to

decrease behavior

(e.g., Time Out)


Four Kinds of ConsequencesFour Kinds of Consequences

Positive(Add)

Negative(Subtract)

STIMULUS

DecreaseBehavior

PositivePunishment

Getting speeding ticketleads to less speeding

PositivePunishment

Missing dinner leads to less staying out late

IncreaseBehavior

PositiveReinforcementBonus for working hard leads to more hard work

NegativeReinforcement

Aspirin relieving headache

leads to more aspirin use

GO

AL


Class DemonstrationClass Demonstration

Establishing a behavior using operant conditioning

• Select a target behavior; be very specific

• Using shaping reinforcing successive approximations of the behavior

• Be careful to reinforce only the target behavior


Types of ReinforcersTypes of Reinforcers

Primary reinforcers – Reinforcers, such as food and sex, that have an innate basis because of their biological value to an organism


Types of ReinforcersTypes of Reinforcers

Secondary reinforcers – Stimuli, such as money or tokens, that acquire their reinforcing power by their learned association with primary reinforcers (also called conditioned reinforcers)


Schedules of ReinforcementSchedules of Reinforcement

Continuous reinforcement – Reinforcement schedule in which all correct responses are reinforced

Partial reinforcement – Reinforcement schedule in which some, but not all, correct responses are reinforced (also called intermittent reinforcement)



Ratio schedules – Provide reward after a certain number of responses

Interval schedules – Provide reward after a certain time interval

Fixed Ratio (FR)Fixed Ratio (FR)

Fixed Interval (FI)Fixed Interval (FI)

Variable Ratio (VR)Variable Ratio (VR)

Variable Interval (VI)Variable Interval (VI)



Fixed Ratio (FR)Fixed Ratio (FR)

Fixed Interval (FI)

Variable Ratio (VR)

Variable Interval (VI)

Rewards appear after a certain set number of responses

e.g. factory workers getting paid after every 10 cases of product are completed



Fixed Ratio (FR)

Fixed Interval (FI)

Variable Ratio Variable Ratio (VR)(VR)


Rewards appear after a certain number of responses, but that number varies from trial to trial

e.g. slot machine pay-offs



Fixed Ratio (FR)

Fixed Interval Fixed Interval (FI)(FI)

Variable Ratio (VR)


Rewards appear after a certain fixed amount of time, regardless of number of responses

e.g. weekly or monthly paychecks



Fixed Ratio (FR)

Fixed Interval (FI)

Variable Ratio (VR)

Variable Interval Variable Interval (VI)(VI)

Rewards appear after a certain amount of time, but that amount varies from trial to trial

e.g. random visits from the boss who delivers praise


How does this differ from extinction in classical conditioning?

Contingencies of ReinforcementContingencies of Reinforcement

Extinction – In operant conditioning, a process by which a response that has been learned is weakened by the absence or removal of reinforcement


PunishmentPunishment

Punishment – An aversive stimulus which diminishes the strength of the response it follows

How does this differ from negative reinforcement?


Punishment vs. Negative Punishment vs. Negative ReinforcementReinforcement

Loud Noise Press Lever

Press Lever

Loud Noise Removed

Loud Noise Applied

Response ConsequenceNegative Reinforcement

Punishment

No Noise


Types of PunishmentTypes of Punishment

Positive punishment – The application of an aversive stimulus after a response

Negative punishment –The removal of an attractive stimulus after a response


Problems of PunishmentProblems of Punishment

Power usually disappears when threat of punishment is removed

PunishmentOften triggers aggression

May inhibit learning new and better responses

Is often applied unequally

When does punishment work?


Alternatives to PunishmentAlternatives to Punishment

Extinction

Reinforcing preferred activitiesPremack principle

Prompting and shaping


Operant and Classical Conditioning Operant and Classical Conditioning ComparedCompared

Classical conditioning involves the association of two stimuli (UCS + CS) before the response or behavior

Operant conditioning involves a reinforcing (reward) or punishing stimulus after a response or behavior


Using Classical and Operant Conditioning Using Classical and Operant Conditioning to Initiate and Sustain Behavior Changeto Initiate and Sustain Behavior Change

Classical Conditioning connects command with behavior

• UCS = tug on leash or pressure on hind legs

• UCR = dog sits

• CS = command (i.e., “Rocky sit”)

• CR = dog sits

Operant conditioning behavior is repeated

• Give praise or food reward following CR

• Use intermittent reinforcement to prevent extinction


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Cognitive Cognitive Learning ModelsLearning Models


Kohler: Insight LearningKohler: Insight Learning

Wolfgang Kohler

Disenchanted with behaviorists explanation for learning

Believed that cognition, or mental processes must be essential to learning

Observational studies of chimpanzees


Insight LearningInsight Learning

Problem – bananas hung outside of chimp’s reach

Initial solutions

Pile up boxes and climb on top

Use sticks to knock the fruit down



Insight learningsolve complex problems by combining simpler,

previously learned responsesProblem-solving occurs through sudden

reorganization of perceptions

Placed bananas higher up – neither previously learned solutions sufficient to get the fruit



When unable to reach the fruitFirst – threw the sticks away and kicked the wall

Later, piled up the boxes, grabbed the stick, climbed on the boxes and knocked the fruit down with the stick

Cannot be explained through either operant or classical conditioning alone


Kohler’s ChimpsKohler’s Chimps


Tolman: Cognitive MapsTolman: Cognitive Maps

Cognitive mapsMental representations or images that help

organisms navigate through the world

Reinforcement has a greater impact on performance than on learning

i.e., reinforcement serves to motivate the animal to demonstrate what it has learned


Diagram of a Tolman MazeDiagram of a Tolman Maze


Cognitive MapsCognitive Maps

Three groups of rats

1) No reinforcement

2) Reinforced on every trial

3) No reinforcement for first ten trials; reinforced on all subsequent trials


Error Curve Error Curve by Day and Food Deprivationby Day and Food Deprivation


Maze LearningMaze Learning

StartFood/ Goal

Box

A B


Cognitive MapsCognitive Maps

Tolman hypothesized that the rats developed cognitive maps of the mazei.e., Visual/spatial Image or representation of physical

space that is used to navigate through the environment

Demonstrated latent learning – learning that takes place in the absence of reinforcementreinforcement necessary to demonstrate acquisition


Bandura: Social Learning TheoryBandura: Social Learning Theory

Observational LearningAcquisition of behaviors that results from

observation rather than direct experience

E.g., Children learn do cartwheels and

handstands Learn what clothes to wear to fit in (e.g.,

midriffs; low-riser jeans) Learn aggressive behavior


Social Learning TheorySocial Learning Theory

Modeling – imitation and reproduction of behaviors of models

Model must be salient (i.e., are attractive, have high status, and are similar to observer)

Parents, peers, siblings, celebrities



Vicarious reinforcement Learn about the consequences of a behavior by

observing a model engage in the behavior and experience consequences

Outcome ExpectanciesLearned association between a specific

behavior and a specific consequence ORBelief about the consequences of our behavior



Outcome expectancies

Alcohol makes me relaxed and sociableWearing brown polyester will make me a social

outcastIf I study for the exam, I will get a good gradeIf I eat those cookies, I will feel goodHaving sex without a condom will result in

enhanced pleasure



Positive outcome expectanciesBelief that the behavior will result in reinforcing

or rewarding outcomes

Negative outcome expectanciesBelief that the behavior will result in punishing

or negative outcomes



Expectancies influence subsequent behavior

Positive expectancy (i.e., belief that behavior results in reinforcing outcomes) engage in or repeat behavior

Negative expectancy (i.e., belief that behavior results in punishing outcomes) avoid or discontinue behavior


Aggressive BehaviorAggressive Behavior

Children observed a model behave aggressively toward the BOBO doll

Were more likely to behave aggressively when given the opportunity to play with the BOBO doll

Especially when the model was reinforced for his/her aggressive behavior

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