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Exam 2 Results
• Top Score: 49• Mean: 35.80• Bimodal: 34 and 37• Median: 36• Standard Deviation: 5.81• To calculate your approximate grade, divide 49 by
your score.– Example:
• 36/49 = 73.5% = C
2
Learning
Chapter 8
3
Learning
How Do We Learn?
Classical Conditioning Pavlov’s Experiments Extending Pavlov’s
Understanding Pavlov’s Legacy
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Learning
Operant Conditioning Skinner’s Experiments Extending Skinner’s
Understanding Skinner’s Legacy Contrasting Classical & Operant
Conditioning
5
Learning
Learning by Observation Bandura’s Experiments Applications of Observational
Learning
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Definition
Learning is a relatively permanent change in anorganism’s behavior due to experience.
Learning is more flexible in comparison to thegenetically-programmed behaviors of Chinooks,
for example.
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How Do We Learn?
We learn by association. Our mindsnaturally connect events that occur in
sequence.2000 years ago, Aristotle suggested thislaw of association. Then 200 years agoLocke and Hume reiterated this law.
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Stimulus-Stimulus Learning
Learning to associate one stimuluswith another.
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Stimulus-Stimulus Learning
Learning to associate one stimuluswith another.
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Response-Consequence Learning
Learning to associate a responsewith a consequence.
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Response-Consequence Learning
Learning to associate a responsewith a consequence.
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Ideas of classical conditioning originate from oldphilosophical theories. However, it was the
Russian physiologist Ivan Pavlov who elucidatedclassical conditioning. His work provided a basisfor later behaviorists like John Watson and B. F.
Skinner.
Classical Conditioning
Ivan Pavlov (1849-1936)
Sovf
oto
3
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Pavlov’s Experiments
Before conditioning, food (UnconditionedStimulus, US) produces salivation
(Unconditioned Response, UR). However, thetone (neutral stimulus) does not.
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Pavlov’s Experiments
During conditioning, the neutral stimulus (tone)and the US (food) are paired, resulting in
salivation (UR). After conditioning, the neutralstimulus (now Conditioned Stimulus, CS) elicits
salivation (now Conditioned Response, CR)
15
AcquisitionAcquisition is the initial stage in classical
conditioning in which an association between aneutral stimulus and an unconditioned
stimulus takes place.
In most cases, for conditioning to occur, theneutral stimulus needs to come before theunconditioned stimulus.
The time in between the two stimuli shouldbe about half a second.
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Acquisition
The CS needs to come half a second before the USfor acquisition to occur.
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Extinction
When the US (food) does not follow the CS(tone), CR (salivation) begins to decrease and
eventually causes extinction.
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Spontaneous Recovery
After a rest period, an extinguished CR (salivation)spontaneously recovers, but if the CS (tone) persists
alone, the CR becomes extinct again.
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19
Stimulus Generalization
Tendency to respond tostimuli similar to the CS is
called generalization.Pavlov conditioned thedog’s salivation (CR) by
using miniature vibrators(CS) on the thigh. When he
subsequently stimulatedother parts of the dog’s
body, salivation dropped.20
Stimulus Discrimination
Discrimination is the learned ability to distinguishbetween a conditioned stimulus and other stimuli that
do not signal an unconditioned stimulus.
21
Extending Pavlov’s Understanding
Pavlov and Watson considered consciousness,or mind, unfit for the scientific study of
psychology. However, they underestimatedthe importance of cognitive processes and
biological constraints.
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Cognitive Processes
Early behaviorists believed that learnedbehaviors of various animals could be reduced
to mindless mechanisms.
However, later behaviorists suggested thatanimals learn the predictability of a stimulus,
meaning they learn expectancy or awareness of astimulus (Rescorla, 1988).
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Biological Predispositions
Pavlov and Watson believed that laws oflearning were similar for all animals.
Therefore, a pigeon and a person do not differin their learning.
However, behaviorists later suggested thatlearning is constrained by an animal’s biology.
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Biological Predispositions
John Garcia
Garcia showed that the durationbetween the CS and the US may be
long (hours), but yet result inconditioning. A biologically adaptiveCS (taste) led to conditioning and not
to others (light or sound).
Courtesy of John Garcia
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Biological Predispositions
Even humans can develop classically toconditioned nausea.
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Pavlov’s greatest contributionto psychology is isolating
elementary behaviors frommore complex ones through
objective scientificprocedures.
Pavlov’s Legacy
Ivan Pavlov(1849-1936)
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Watson used classicalconditioning procedures to
develop advertisingcampaigns for a number of
organizations, includingMaxwell House, making the“coffee break” an American
custom.
Applications of ClassicalConditioning
John Broadus Watson
Brown Brothers
See also, “Little Albert” experiment28
Two Famous John Watson Quotes• “Psychology as the behaviorist views it is a purely objective experimental branch
of natural science. Its theoretical goal is the prediction and control of behavior.Introspection forms no essential part of its methods, nor is the scientific value ofits data dependent upon the readiness with which they lend themselves tointerpretation in terms of consciousness. The behaviorist, in his efforts to get aunitary scheme of animal response, recognizes no dividing line between manand brute. The behavior of man, with all of its refinement and complexity, formsonly a part of the behaviorist's total scheme of investigation.”
• “Give me a dozen healthy infants, well-formed, and my own specifiedworld to bring them up in and I'll guarantee to take any one at randomand train him to become any type of specialist I might select -- doctor,lawyer, artist, merchant-chief and, yes, even beggar-man and thief,regardless of his talents, penchants, tendencies, abilities, vocations,and race of his ancestors. I am going beyond my facts and I admit it,but so have the advocates of the contrary and they have been doing itfor many thousands of years.”(1930)
29
Alcoholics may be conditioned (aversively)by reversing their positive-associations withalcohol.
Through classical conditioning, a drug (plusits taste) that affects the immune responsemay cause the taste of the drug to invoke theimmune response.
Applications of ClassicalConditioning
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Operant & Classical Conditioning
1. Classical conditioningforms associationsbetween stimuli (CSand US). Operantconditioning, on theother hand, forms anassociation betweenbehaviors and theresulting events.
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31
Operant & Classical Conditioning
Classical conditioning involves respondentbehavior that occurs as an automaticresponse to a certain stimulus. Operantconditioning involves operant behavior, abehavior that operates on the environment,producing rewarding or punishing stimuli.
32
Skinner’s ExperimentsSkinner’s experiments extend Thorndike’s
thinking, especially his law of effect. This lawstates that rewarded behavior is likely to occur
again.
Yale U
niversity Library
33
Operant Chamber
Using Thorndike's law of effect as a startingpoint, Skinner developed the Operant chamber,
or the Skinner box, to study operantconditioning.
Walter D
awn/ Photo Researchers, Inc. Fr
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34
Operant Chamber
The operant chamber,or Skinner box, comeswith a bar or key that
an animal manipulatesto obtain a reinforcer
like food or water. Thebar or key is connectedto devices that recordthe animal’s response.
35
Shaping
Shaping is the operant conditioning procedurein which reinforcers guide behavior towards the
desired target behavior through successiveapproximations.
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.
36
Types of Reinforcers
Any event that strengthens the behavior itfollows. A heat lamp positively reinforces a
meerkat’s behavior in the cold.
Reuters/ Corbis
7
37
Primary Reinforcer: An innately reinforcingstimulus like food or drink.
Conditioned Reinforcer: A learnedreinforcer that gets its reinforcing powerthrough association with the primaryreinforcer.
Primary & Secondary Reinforcers
38
Immediate Reinforcer: A reinforcer thatoccurs instantly after a behavior. A rat getsa food pellet for a bar press.
Delayed Reinforcer: A reinforcer that isdelayed in time for a certain behavior. Apaycheck that comes at the end of a week.
Immediate & Delayed Reinforcers
We may be inclined to engage in small immediatereinforcers (watching TV) rather than large delayedreinforcers (getting an A in a course) which require
consistent study.
39
Reinforcement Schedules
1. Continuous Reinforcement: Reinforces thedesired response each time it occurs.
2. Partial Reinforcement: Reinforces aresponse only part of the time. Though thisresults in slower acquisition in thebeginning, it shows greater resistance toextinction later on.
40
Ratio Schedules
Fixed-ratio schedule: Reinforces a responseonly after a specified number of responses.e.g., piecework pay.
Variable-ratio schedule: Reinforces aresponse after an unpredictable number ofresponses. This is hard to extinguish becauseof the unpredictability. (e.g., behaviors likegambling, fishing.)
41
Interval Schedules
Fixed-interval schedule: Reinforces aresponse only after a specified time haselapsed. (e.g., preparing for an examonly when the exam draws close.)
Variable-interval schedule: Reinforces aresponse at unpredictable timeintervals, which produces slow, steadyresponses. (e.g., pop quiz.)
42
Schedules of Reinforcement
8
43
Punishment
An aversive event that decreases the behavior itfollows.
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Punishment
1. Results in unwanted fears.2. Conveys no information to the organism.3. Justifies pain to others.4. Causes unwanted behaviors to reappear in its
absence.5. Causes aggression towards the agent.6. Causes one unwanted behavior to appear in
place of another.
Although there may be some justification foroccasional punishment (Larzelaere & Baumrind,
2002), it usually leads to negative effects.
45
Extending Skinner’s Understanding
Skinner believed in inner thought processes andbiological underpinnings, but many
psychologists criticize him for discountingthem.
46
Cognition & Operant Conditioning
Evidence of cognitive processes during operantlearning comes from rats during a maze
exploration in which they navigate the mazewithout an obvious reward. Rats seem to
develop cognitive maps, or mentalrepresentations, of the layout of the maze
(environment).
47
Latent Learning
Such cognitive maps are based on latentlearning, which becomes apparent when anincentive is given (Tolman & Honzik, 1930).
48
MotivationIntrinsic Motivation:The desire to perform abehavior for its ownsake.
Extrinsic Motivation:The desire to perform abehavior due topromised rewards orthreats of punishments.
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49
Biological Predisposition
Biological constraintspredispose organisms to
learn associations thatare naturally adaptive.Breland and Breland(1961) showed that
animals drift towardstheir biologically
predisposed instinctivebehaviors.
Marian Breland Bailey
Photo: Bob Bailey
50
Skinner’s Legacy
Skinner argued that behaviors were shaped byexternal influences instead of inner thoughts and
feelings. Critics argued that Skinnerdehumanized people by neglecting their free will.
Falk/ Photo Researchers, Inc.
51
Applications of OperantConditioning
Skinner introduced the concept of teachingmachines that shape learning in small steps and
provide reinforcements for correct rewards.
In School
LWA
-JDL/ C
orbis
52
Applications of OperantConditioning
Reinforcement principles can enhance athleticperformance.
In Sports
53
Applications of OperantConditioning
Reinforcers affect productivity. Many companiesnow allow employees to share profits and
participate in company ownership.
At work 54
Applications of OperantConditioning
In children, reinforcing good behavior increasesthe occurrence of these behaviors. Ignoring
unwanted behavior decreases their occurrence.
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55
Operant vs. Classical Conditioning
56
Learning by Observation
Higher animals,especially humans,
learn through observingand imitating others.
The monkey on theright imitates the
monkey on the left intouching the pictures ina certain order to obtain
a reward.
© H
erb Terrace
©H
erb Terrace
57
Mirror Neurons
Neuroscientists discovered mirror neurons inthe brains of animals and humans that are active
during observational learning.
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Imitation Onset
Learning by observationbegins early in life. This
14-month-old childimitates the adult on TV
in pulling a toy apart.
Mel
tzof
f, A
.N. (
1998
). Im
itatio
n of
tele
vise
d m
odel
s by
infa
nts.
Chi
ld D
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ent,
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1229
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tos C
ourte
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f A.N
. Mel
tzof
f and
M. H
anuk
.
59
Bandura's Experiments
Bandura's Bobo dollstudy (1961) indicated
that individuals(children) learn
through imitatingothers who receive
rewards andpunishments.
Cour
tesy
of A
lber
t Ban
dura
, Sta
nfor
d U
nive
rsity
60
Applications of ObservationalLearning
Unfortunately,Bandura’s studies
show that antisocialmodels (family,
neighborhood or TV)may have antisocial
effects.
11
61
Positive Observational Learning
Fortunately, prosocial (positive, helpful) modelsmay have prosocial effects.
Bob
Dae
mm
rich/
The
Imag
e W
orks
62
Television and ObservationalLearning
Gentile et al., (2004)shows that children in
elementary schoolwho are exposed toviolent television,videos, and video
games expressincreased aggression.
Ron
Cha
pple
/ Tax
i/ G
etty
Imag
es
63
Modeling Violence
Research shows that viewing media violenceleads to an increased expression of aggression.
Children modeling after pro wrestlers
Bob
Dae
mm
rich/
The
Imag
e W
orks
Gla
ssm
an/ T
he Im
age
Wor
ks