Theories of personality

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chapter 9
Learning
Learning Objectives:
1. What are the two types of stimuli and responses that
form the basis of classical conditioning?
Behaviorism
• Part of the LEARNING PERSPECTIVE
• Focus on observable behaviors, rather than what
goes on in the mind
• The environment determines our behaviors
• Conditioning = the association between environmental stimuli
and behavioral responses
• Learning = conditioning
• Classical conditioning
• Operant conditioning
• John Watson
• Founded behaviorism
• Psychology should only consider observable behaviors, so
humans can be studied objectively
chapter 9
John Watson
Famous Quote:
“Give me a dozen healthy infants, well-formed,
and my own special world to bring them up in,
and I’ll guarantee to take any one at random and
train him to be any type of specialist I might
select—doctor, lawyer, artist, merchant-chief,
and yes, beggar-man and thief, regardless of his
talents, penchants, tendencies, abilities,
vocations, and race of his ancestors.”
chapter 9
Definitions
• What is Learning?
• A relatively permanent change in behavior due to experience
• What is Conditioning?
• The association between environmental stimuli and the
organism’s responses
chapter 9
Classical conditioning
The process by which a previously neutral stimulus
acquires the capacity to elicit a response
through association with a stimulus
that already elicits a similar response
chapter 9
Classical conditioning
Ivan Pavlov
• studies on dog salivation
• observed that dogs salivated BEFORE food was placed in its mouth
• conditional “reflex”
 Translated into conditioned
chapter 9
Classical Conditioning
Unconditioned stimulus (US)
Elicits a response in the absence of
learning
Unconditioned response (UR)
The reflexive response to a stimulus
in the absence of learning
S-R Pair that is instinctive/innate
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Classical Conditioning
Learning occurs when a neutral stimulus is then regularly
paired with an unconditioned stimulus.
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Classical Conditioning
Conditioned stimulus (CS)
An initially neutral stimulus that
comes to elicit a conditioned
response after being paired with an
unconditioned stimulus
Conditioned response (CR)
A response that is elicited by the
conditioned stimulus
– Occurs after the CS has been
associated with the US
– Similar to the US
– A learned response
S-R Pair is learned
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Classical Conditioning:
Eye-Blink Experiment
whistle
Puff of air from
straw
Eye-blink
What are the unconditioned stimulus (US) and
unconditioned response (UR) ?
chapter 9
Classical Conditioning:
Eye-Blink Experiment
Puff of air from
straw
US
Eye-blink
UR
chapter 9
Classical Conditioning:
Eye-Blink Experiment
whistle
Puff of air from
straw
What are the conditioned stimulus and
conditioned response?
Eye-blink
chapter 9
Classical Conditioning:
Eye-Blink Experiment
+
whistle
Puff of air from
straw
Eye-blink
Neutral Stimulus
US
UR
chapter 9
Classical Conditioning:
Eye-Blink Experiment
whistle
CS
Eye-blink
CR
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Another example
When Alan feeds his fish, he first turns on the aquarium
light and then puts in the fish food. After a while he
notices that they swim to the top as soon as he turns on
the aquarium light. What is the conditioned stimulus
1.
2.
3.
4.
Fish food
The aquarium light
The aquarium
Alan
Last Class in Review
• Behaviorism (learning perspective)
• Observable behaviors
• Learning = Conditioning
– Environment determines behaviors
• John Watson
• Learning
– Relatively permanent change in behavior
• Classical Conditioning
–
–
–
–
Unconditioned Stimulus – elicits reflexive behavior
Unconditioned Response – reflexive behavior
Conditioned Stimulus – elicits learned behavior
Conditioned Response – learned behavior
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Learning
Learning Objectives:
1. How does the process of extinction work in classical
conditioning? What is spontaneous recovery?
2. What do stimulus generalization and discrimination
refer to in classical conditioning?
3. How can classical conditioning help us to learn
emotional responses to objects, people, and places?
4. How do the principles of classical conditioning
contribute to food aversions and reactions to medical
treatments?
•
•
Classical Conditioning
Review
Geraldine has an automobile accident at the corner of 32nd street and
Cherry Ave. Whenever she approaches the intersection now, she
begins to feel uncomfortable; her heart begins to beat faster, she gets
butterflies in her stomach, and her palms become sweaty.
– US:
– UR:
– CS:
– CR:
Calvin was chased and assaulted by an aggressive rooster when he
was barely three years old. As an adult he still gets little blips in his
stomach when he hears the word rooster and he claims that birds make
him nervous.
– US:
– UR:
– CS:
– CR:
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Principles of classical
conditioning
Extinction
Spontaneous recovery
Higher-order conditioning
Stimulus generalization
Stimulus discrimination
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Extinction
Whistle
Eye-blink
CS
CR
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Extinction
The weakening and eventual
disappearance of a learned
response
In classical conditioning, it
occurs when the conditioned
stimulus is no longer paired
with the unconditioned
stimulus.
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Extinction
The weakening and eventual
disappearance of a learned
response
In classical conditioning, it
occurs when the conditioned
stimulus is no longer paired
with the unconditioned
stimulus.
Spontaneous Recovery
• The reappearance of a learned response
after its apparent extinction
• Eye-Blink Example:
We extinguished your learned response of eye-blinking
(CR) to a whistle by not pairing the whistle (CS) with the
puff of air (US); however, if tomorrow you are walking
down the street and hear a policeman blow a whistle
your eye might blink (CR). This would be spontaneous
recovery, or the reappearance of a response, after
extinction has occurred.
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Higher-order conditioning
A neutral stimulus can become a conditioned
stimulus by being paired with an existing
conditioned stimulus.
Neutral stimulus
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Higher-order conditioning
A neutral stimulus can become a conditioned
stimulus by being paired with an existing
conditioned stimulus.
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Stimulus generalization
In classical conditioning, occurs when a new
stimulus that resembles the conditioned stimulus
elicits the conditioned response
Teapot
whistle
Similar to
CS
Eye-blink
CR
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Stimulus discrimination
The tendency to respond differently to two or more
similar stimuli
In classical conditioning, occurs when a stimulus
similar to the conditioned stimulus fails to evoke a
conditioned response
Train
whistle
Eye-blink
Similar to
CS
CR does
not occur
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What is learned in
classical conditioning?
We learn that the first stimulus predicts the
second.
For classical conditioning to be most effective,
the stimulus to be conditioned should precede
the unconditioned stimulus.
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Learning to like
Where do sentimental feelings come
from?
Objects have been associated in the past
with positive feelings.
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Classical Conditioning and Emotions
Pre-9/11
Neutral Stimulus
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Classical Conditioning and Emotions
Sadness
Neutral Stimulus
Anxiety
Fear
Events of 9/11
US
UR
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Classical Conditioning and Emotions
CS
CR
Sadness
Anxiety
Fear
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Classical Conditioning in
Advertisements
Advertisers use attractive women, pop icons, and
popular music to attract us to products
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Learning to fear
We can learn fear through association.
Phobias
“Little Albert” experiment –
- Watson and Raynor
- Established rat phobia in 11-month old boy though classical conditioning
- Fear generalized to other furry objects (stimulus generalization)
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Unlearning fear
Counterconditioning
The process of pairing a conditioned stimulus with a stimulus that
elicits an incompatible response.
Systematic Desensitization
A variation on counterconditioning developed for the treatment of
phobias
Rod’s Story
From the time he was 5, Rod’s favorite food was peanut butter. Some days he
would eat it right out of the jar. Other days he would make elaborate
sandwiches with layers of peanut butter, jelly and bananas. His mother would
allow him to eat only 2 of these at any one time. There were days when Rod
waited for hours to have his peanut butter at night, on top of ice cream. He
would keep eating the peanut butter off the top and piling on more, until his
mom said, “That’s enough, Rod”. Rod’s favorite times were when he and his
dog would eat peanut butter together. He would take a spoonful for himself and
give one to the dog. The only thing that stopped him from eating the whole
thing was his mother’s warning that it would make the dog sick.
Then came a day when his mom was called to help a neighbor and told Rod “I’ll
be back in an hour. You be good”. Rod new exactly what he would do, he got
out a full jar of Peanut butter, a spoon, and sat down with his dog. They ate the
PB spoonful by spoonful until the jar was al gone. When Rod’s mother
returned she found him on the couch. He said he felt sick and the dog looked
sick too. As Rod became more nauseated, he had to vomit. For the first time
in his entire life he hated the taste of PB. He couldn’t even stand the thought of
eating it. Ten years passed before he was able to eat it again. Although he can
eat it now, his passion for it has never returned.
Adapted from Rod Plotnick, Intro to Psychology 2nd edition
chapter 9
Taste Aversions
Food Aversions
- What are the unconditioned stimulus
and unconditioned response?
- What are the conditioned stimulus and
conditioned response?
chapter 9
Classical conditioning and medical treatments
Cancer patients undergoing chemotherapy often react to waiting
rooms with nausea
Why?
What are the conditioned stimulus and conditioned response?
What are the unconditioned stimulus and response?
How might placebos sometimes give patients real relief?
Applying Classical Conditioning
• While caring for your friend’s dog, you notice that it displays a
fear-like posture as you roll up the newspaper. You try this
several more times and become convinced that this dog is
generally afraid of the rolled-up newspapers
US:
UR:
CS
CR:
• If the dog was also afraid of magazines (and wasn’t ever hit with
a magazine), what might this be an example of
Applying Classical Conditioning
• Joan, an animal trainer, has been phobic about monkeys since
an earlier attack. However, because of the money, she has
agreed to work with monkeys for a movie studio. At first, just
going anywhere near the cages makes Joan tense, sweaty, and
apprehensive. Lately though things have changed. Working
with such cuddly, affectionate, human-like creatures is causing
Joan to wonder why she ever felt such extreme distress.
US:
UR:
CS:
CR:
• What other principles of classical conditioning are at play here?
Applying Classical Conditioning
• At a red light, Bob and Fred automatically tensed and
felt chills when they heard the screech of tires behind
them. Later, while watching a car race, Bob
remarked how the screeching of tires was having little
effect on him. Fred agreed and wondered why they
reacted at all, because neither had as much as a
dent on his driving record.
• What principles of classical conditioning do you see
here?
Applying Classical Conditioning
•
Early in their relationship, the mere sight of Donna excited Jack. This
gradually died out; however, as Donna behaved tolerantly, but
indifferently. When the relationship ended, Jack was bored with Donna
and didn’t even think about her for the next year. Now, he was
surprised at how excited he was becoming at seeing Donna through
the window of a bus.
US:
UR
CS:
CR:
•
What principles of classical conditioning do you see here?
Applying Classical Conditioning
• Bill couldn’t ever remember being so sick and
nauseated. He would never go to that restaurant
again or eat chicken again. All he could think about
was the good dinner his mother was going to prepare
for his homecoming. When he walked in the kitchen,
he became flushed and felt nauseated when he saw
a brown turkey sitting on the dinner table.
US:
UR:
CS:
CR:
• What principles of classical conditioning do you see
here?
Last Class in Review
• Principles of Classical Conditioning
– Extinction
• CS is no longer paired with US and the CR eventually disappears
– Spontaneous Recovery
• Reappearance of CR after apparent extinction
– Higher-order conditioning
• Pairing of a neutral stimulus with CS, where neutral stimulus become new
CS
– Stimulus generalization
• When a stimulus that is different, but similar to CS, elicits the CR
– Stimulus Discrimination
• When a stimulus that is similar to the CS, fails to elicit the CR
• What is learned with Classical Conditioning
– That 1 stimulus predicts a second
– Emotions
• Learning to like –objects and places evoke emotions, advertisements
• Learning to fear – “Little Albert” experiment
– Counterconditioning
• Taste Aversions
• Medical Treatments
Operant Conditioning
•
Learning Objectives:
1. What are 3 types of consequences that a behavior might
produce?
2. What is the difference between positive reinforcement and
negative reinforcement in operant conditioning?
3. How do extinction, generalization, and discrimination take
place in operant conditioning? How are these processes
different than in classical conditioning?
4. What is the difference between a continuous and
intermittent schedule of reinforcement?
5. How could you use shaping of approximations to train a
chicken to play tic-tac-toe?
6. What are 6 reasons punishments usually fail to change
behavior?
7. Under what circumstances might rewards backfire?
chapter 9
Operant conditioning
(aka Instrumental Learning)
The process by which a response/behavior
becomes more or less likely to occur
depending on its consequences
Let’s consider our example:
John’s behavior (choosing the apple)
became MORE likely because of the
consequence (getting praise and a toy)
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Operant conditioning
(aka Instrumental Learning)
How is this different than Classical
Conditioning?
- For classical conditioning it does NOT matter
what happens after the behavior
- Classical conditioning more reflexive
- Operant conditioning more complex and voluntary
- “operating” on the environment
Operant Conditioning:
Edward Thorndike (1874-1949)
• Famous experiment
– How cats escape from puzzle boxes
• Law of Effect
– Responses closely followed by satisfying
consequences are more likely to recur
– Responses followed by aversive
consequences they are less likely to recur
Operant Conditioning:
B.F. Skinner (1904-1990)
• Radical Behavioralism
– Reworked Thorndike’s Law of Effect into
Operant Conditioning
– Distinguished from John Watson and
Classical Conditioning
– To understand behavior we must focus on
the external causes and consequences
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Consequences of behavior
1.
Neutral consequence:
neither increases nor
decreases the probability
that the response will
recur.
2.
Reinforcement:
strengthens the response
or makes it more likely to
recur
3.
Using the potty
Punishment: weakens a
response or makes it less
likely to recur
Response become
more likely
Detention
Sleeping in class
Response becomes
less likely
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Reinforcement
A stimulus strengthens or increases the
probability of the response that it follows.
Primary reinforcers are inherently reinforcing and typically satisfy
a physiological need.
- Food, water, caressing, comfortable air temperature
Secondary reinforcers are stimuli that have acquired reinforcing
properties through associations with other reinforcers.
- money, praise, good grades, awards
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Types of reinforcement
Positive reinforcement (+)
When a pleasant consequence
follows a response, making the
response more likely to recur.
Negative reinforcement (-)
When an unpleasant consequence
is removed following a response,
making the response more likely
to recur.
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Types of reinforcement
Positive reinforcement (+)
When a pleasant consequence
follows a response, making the
response more likely to recur.
Negative reinforcement (-)
When an unpleasant consequence
is removed following a response,
making the response more likely
to recur.
Toy = pleasant
consequence
John is more
likely to choose
the apple in the
future
Aspirin removed
headache (unpleasant
event)
Teacher more likely
to take aspirin in the
future
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Punishment
The process by which a stimulus weakens or
reduces the probability of the response that it
follows.
Primary punishers are inherently punishing.
- pain (e.g. hitting), extreme heat/cold
Secondary punishers are stimuli that have acquired punishing
properties through associations with other punishers.
- criticism, demerits, scolding, bad grades, fines
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Types of punishment
Positive punishment
When an unpleasant consequence
follows a response, making the
response less likely to recur.
Negative punishment
When an pleasant consequence is
removed following a response,
making the response less likely to
recur.
chapter 9
Types of punishment
Jail = unpleasant
consequence
Positive punishment
When an unpleasant consequence
follows a response, making the
response less likely to recur.
Man less likely to
commit crime again
Time Out = Removal of
pleasant consequences
(toys, time with friends)
Negative punishment
When an pleasant consequence is
removed following a response,
making the response less likely to
recur.
Aggressive Behavior
Aggressive Behavior
less likely
Rewards and Punishments
Positive
(adding)
Negative
(subtracting)
Reinforcement
Giving a
pleasant
consequence
Punishment
Giving an
unpleasant
consequence
Taking away an
unpleasant
consequence
Taking away a
pleasant
consequence
Increase Response
Decrease Response
Rewards and Punishments
Positive
Stimulus
Increase Behavior
Decrease Behavior
Positive
Reinforcement
(add stimulus)
Negative
Punishment
(remove stimulus)
Negative
Negative
Reinforcement
Stimulus (remove stimulus)
Positive
Punishment
(add stimulus)
chapter 9
Your turn
Your first time camping in the woods, you are bitten over
45 times by mosquitoes, resulting in lots of swollen,
itchy bumps on your arms, legs, and back. You never
want to go camping again. What kind of consequence
did you confront on your first camping experience?
1.
2.
3.
4.
Positive reinforcement
Negative reinforcement
Positive punishment
Negative punishment
chapter 9
The Skinner box
A cage equipped with device that delivers food or water
when an animal makes a desired response
chapter 9
The Skinner box
• At first the animal accidentally presses the lever and is rewarded with food or
water
• After this behavior occurs accidentally several times, the animal learns that if
he presses the lever, food will follow
•The behavior (pressing the lever) increases because food is a reinforcement
chapter 9
Principles of operant
conditioning
Extinction
In operant conditioning, occurs when a response is no longer followed by a
reinforcer
“My first extinction curve showed up by accident. A rat was pressing the
lever in an experiment on satiation when the pellet dispenser jammed. I
was not there at the time, and when I returned I found a beautiful curve.
The rat had gone on pressing although no pellets were received.…”
B.F. Skinner
No
toy
Apple choosing behavior
decreases and eventually
disappears
Spontaneous Recovery
The reappearance of a learned and extinguished behavior
chapter 9
Principles of operant
conditioning
Stimulus generalization
The tendency for a behavioral response that has been reinforced (or
punished) in the presence of one stimulus to occur (or be suppressed) in
the presence of a similar stimulus
Substitute teacher
(stimulus similar to
regular teacher)
Stimulus discrimination
The tendency of responses to occur in the presence of one stimulus but
not another that differs from it on some dimension
Aunt Martha
(stimulus different
than teacher)
Behavior
doesn’t
occur
chapter 9
Principles of operant
conditioning
Stimulus generalization
Pigeon pecks to get reward
in response to both circle
(original stimulus) and oval
(similar stimulus)
Stimulus discrimination
To teach stimulus discrimination:
FOOD
Pigeon learns to
discriminate between the 2
stimuli and peck only in
when the circle is shown
NO
FOOD
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Schedules of reinforcement
Continuous
Every occurrence of a response is reinforced.
- learning is most rapid
- extinction rapid
Intermittent (partial)
Only some occurrences of a response are reinforced.
- Response more resistant to extinction
- Fixed-ratio, fixed-interval, variable-ratio, variable-interval
chapter 9
Schedules of
reinforcement
Simple reinforcement
schedules produce
characteristic
response patterns.
chapter 9
Continuous vs. Partial reinforcement
and Extinction
Intermittent Reinforcement Schedules
• Can you think of any behaviors that might be
explained by intermittent reinforcement?
– Lucky charms/Superstitions
•
•
•
a batter wears a certain hat and gets a home run
a gambler lights up a cigarette and gets blackjack
“Find a penny pick it up, all the day you’ll have good luck”
– Why are these so resistant to extinction?
• They are reinforced on an intermittent schedule
chapter 9
Shaping
An operant conditioning procedure used to
teach complex behaviors by reinforcing
successive approximations of a desired
response
• Getting an animal to do tricks
• Getting a toddler to say water
– Successive Approximations
• Behavioral responses that are reinforced that are increasingly similar
to the desired response
Instinctive drift: the tendency for an organism
to revert to instinctive behavior
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Behavior modification
(aka applied behavioral analysis)
The application of operant conditioning
techniques in a real-world setting
To teach new responses
To reduce or eliminate maladaptive or problematic behavior
What types of situations might this be used in?
• Toilet Training
• Elimination of bad habits (smoking, nail biting)
• Therapy for autistics
chapter 9
Behavior modification
for Autism
1.
2.
3.
4.
Select a target behavior (making eye contact)
Have child sit in chair facing you
Give command “Look at me” every 5-10 seconds
Reward the child with praise and food for correctly
looking you
•
5.
6.
(adapted from Lovas, 1981)
Remember successive approximations
Repeat step 3 until the child is repeatedly following
the command “Look at me”.
Gradually increase the duration of eye contact to 23 second with praise throughout the time at first
and then only after the requisite amount of time
has passed.
chapter 9
What conditions are needed for
punishment to work?
1. It needs to immediately follow the behavior
2. It is better if it is mild rather than harsh
3. It needs to be consistent
chapter 9
Why do punishments often fail?
1.
If the punishment is administered inappropriately
•
2.
When the recipient responds with anxiety, fear, or rage
•
3.
Blind rage, shouting obscenities
Classical conditioning may cause the punishment to generalize to
the place, person, or circumstances surrounding the punishment
Punishments are often only effective temporarily or
under certain circumstances
•
Only when parents are around
4.
When it does not immediately follow the behavior
5.
When it does not inform the recipient how it might be
avoided in the future
6.
When a consequence thought to be a punishment proves
to be reinforcing
chapter 9
When are rewards bad?
If external reinforcers undermine internal
reinforcers
External reinforcers
Reinforcers not inherently related to the behavior being reinforced
- money, praise, gold stars
Internal reinforcers
Reinforcers inherently related to the behavior being reinforced
- enjoyment, satisfaction
Last Class in Review
• Operant Conditioning
– The process through which a behavior becomes more or less likely
depending on its consequences
– Edward Thorndike
• Cat puzzle boxes
• Law of Effect
– BF Skinner
• Radical behavioralism
• Skinner box
– Consequences of Behavior
• Neutral
• Reinforcement – increases behavior (Positive vs Negative, Primary vs Secondary)
• Punishment – decreases behavior (Positive vs. Negative, Primary vs Secondary)
– Principles of Operant Conditioning
• Extinction, Stimulus Generalization, Stimulus Discrimination, Schedules of
Reinforcement, Shaping (Behavior Modification)
– Conditions needed for Punishments to work
• Why punishments fail
• When are rewards bad
Learning Objectives
•
Learning (finishing up)
1.
2.
What is latent learning and observational learning?
What did the Bobo Doll Study show?
Operant Conditioning Review
• Tim asks his mom for a toy at the store. She says
no. Tim starts to scream and cry and continues to do
so until his mom gets him a toy. Immediately upon
receiving the toy, Tim stops crying. In this example
what is the positive reinforcement and negative
reinforcement?
– Positive reinforcement:
– Negative reinforcement:
Operant Conditioning Review
• Jenny and Johnny’s moms are both trying to potty
train their children. Jenny’s mom gives Jenny a
cookie everytime she goes on the potty, while
Johnny’s mom give Johnny a sticker and praise
everytime he goes on the potty. Who is using the
primary reinforcer and who is using the secondary
reinforcer?
– Primary reinforcer:
– Secondary reinforcer:
Moving on from Behaviorism
• Edward Tolman
Which way
should I go?
Where is that
cheese?
chapter 9
Latent learning
Tolman & Honzik experiment:
3 groups of rats in maze:
1. Always found food at end of maze
2. Never found food
3. No food for 10 days, 11th day
received food
Learning is not ALWAYS
immediately expressed in
performance
A form of learning that is not
immediately expressed as an
overt responses, it occurs
without obvious reinforcement
chapter 9
Social learning theory
Social cognitive theories emphasize how behavior is learned
and maintained.
We learn through observation and imitation of others in a social context
Emphasis on cognitive processes such as plans, expectations, and beliefs
Agree with Behaviorists that learning occurs through operant and classical
conditioning
BUT ADD that for humans cognitive processes (plans,
expectations, beliefs) affect how we learn and what information
we learn
Observational Learning
Observational learning involves learning new
responses by observing the behavior of another
rather than through direct experience
- knowledge results from seeing a model behave in
certain ways and experiencing the consequences
chapter 9
Bandura’s Bobo doll study
Nursery school children watched a film of two men
(Johnny and Rocky) playing with toys.
Johnny refuses to share, and Rocky hits him, getting
all the toys.
Children who watched the video were significantly
more violent afterward than children in a control
group.
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