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CHAPTER 8
LEARNING
What’s In This Chapter?
(Objectives for this Unit)
• This chapter on learning is the
perspective known as Behavioral
• Essential Questions to be asked:
• What is learning?
• Which part of our behavior is
learned?
• What are the types of learning?
"The object of teaching a child
is to enable the child to get
along without the teacher."
unknown
What is Learning?
• A relatively permanent change in an
organism’s behavior due to experience.
Association
 We learn by association
 Our minds naturally connect events that occur in
sequence
 Aristotle 2000 years ago
 John Locke and David Hume 200 years ago
 Associative Learning
 learning that two events occur together
 two stimuli
 a response and its consequences
 Ex. Upward arm motions correlate to positive
position
Conditioning
• Conditioning:
– The acquisition of specific patterns of
behavior in the presence of well-defined
stimuli.
• Classical Conditioning(C.C.):
– a response naturally elicited by one
stimulus comes to be elicited by a different,
formerly neutral stimulus
Ex. Snails on 310
Classical or Pavlovian
Conditioning
 We learn to
associate two
stimuli
Classical Conditioning Terms
• Neutral stimulus:
– A stimulus that does not elicit a specific
response.
• Conditioned stimulus (CS):
– A neutral stimulus that acquires the ability to
elicit a specific response
• Conditioned response (CR):
– A response similar to the UR that is elicited by
the CS.
Classical Conditioning Terms
• Unconditioned stimulus (US):
– A stimulus that always elicits a specific
response in the absence of any training.
• Unconditioned response (UR):
– A response that is always elicited by a specific
stimulus in the absence of any training.
Classical Conditioning
 Ivan Pavlov
 1849-1936
 Russian physician/
neurophysiologist
 Nobel Prize in 1904
 studied digestive
secretions
 First studies on
associative learning
CLASSICAL CONDITIONING
• Nearly all automatic, involuntary responses (UR)
can become a conditioned response:
– heartbeat, sweating, stomach secretion, blood
pressure, brain waves etc.
• For conditioning to be effective, the conditioned
stimulus should occur before the unconditioned
stimulus, not after.
• the conditioned stimulus becomes a kind of
signal for the unconditioned stimulus.
ALL HANDS ON DECK
• 1. Sara is watching a storm. A bolt of lightning is followed
immediately by a huge crash of thunder and makes her
jump. This happens several more times. The storm starts
to move away and there is a gap between the lightening
bolt and the sound of thunder, yet Sara jumps at the
lightening bolt.
• What is the:
• UCS
• UCR
• CS
• CR
ALL HANDS ON DECK
• Steve's mouth waters whenever he eats
anything with lemon in. One day, while
seeing an advertisement showing lemons,
his mouth begins to water.
• What is the:
• UCS
• UCR
• CS
• CR
Can you name the Stimulus?
Classical Conditioning in
Real Life
• Learning to like
• Learning to fear
• Accounting for Taste
• Reacting to Medical Treatment
Classical Conditioning
UCS
(passionate
kiss)
CS
(onion
breath)
CS
(onion
breath)
UCR
(sexual
arousal)
UCS
(passionate
Kiss)
CR
(sexual
arousal)
UCR
(sexual
arousal)
Nausea Conditioning in
Cancer Patients
UCS
(drug)
UCR
(nausea)
CS
(waiting
room)
UCS
(drug)
UCR
(nausea)
CS
(waiting
room)
CR
(nausea)
Acquisition
• Initial stage of classical conditioning with
associating a neutral stimulus with an
unconditional stimulus so that the neutral
stimulus comes to elicit a conditioned response.
– Ex. Flatworms
Principles of Conditioning
•
•
•
•
Discrimination
Generalization
Extinction
Spontaneous recovery
Classical Conditioning
 Discrimination
 in classical conditioning, the learned
ability to distinguish between a CS
and other stimuli that do not signal a
UCS
 Ex. Different types of dogs or snakes
Classical Conditioning
 Generalization
 tendency for stimuli similar to CS
to elicit similar responses
 the extension of the conditioned
response from the original stimulus to
similar stimuli.
 Ex. Children fear cars, truck, and other
moving vehicles
Modification of Original
Classical Conditioning
• Response generalization:
• Stimulus discrimination:
Classical Conditioning
 Extinction
 diminishing of a CR
 in classical conditioning, when a
UCS does not follow a CS
Persistence of Classical
Conditioning
• Spontaneous recovery: the reappearance
of the CR after a pause in extinction trials
Classical Conditioning
Strength
of CR
Acquisition
(CS+UCS)
Extinction
(CS alone)
Spontaneous
recovery of
CR
Extinction
(CS alone)
Pause
•
•
•
•
•
•
ALL HANDS ON DECK
Think about the following scenarios and try to
apply some of the aspects of classical
conditioning:
1. How we acquire likes or dislikes for certain
foods.
2. How classical conditioning may be used to
treat conditions such as alcoholism.
3. How advertisers use classical conditioning.
4. How phobias and fears can be acquired.
5. How phobias and fears could be treated.
Behaviorism
 John B. Watson
 The case of baby Albert”
 Subject: 11 month old baby
Classical Conditioning in
Humans
• J. B. Watson classically conditions “Little
Albert” to fear white rats.
• Case study
• Identify the u.s., u.r., c.s., c.r.
• Discrimination and generalization
The Case of Baby Albert
Classical Conditioning in
Humans
• Mary Cover Jones reconditions “Peter” to
not fear rabbits.
• This procedure evolved into
desensitization therapy.
• The Case of Baby Peter
• Ucs, cs, ucr, cr
Common Examples of Classical
Conditioning
• Phobias:
– Irrational fears
• Conditioned food (taste) aversion:
– Classically conditioning a novel flavor to
illness
– Biological predispositions for serve as
protective measures
Classical Conditioning Is
Selective
• Martin Seligman has used the concept of
preparedness to account for the fact that
certain conditioned responses are
acquired very easily.
• The ease with which we develop
conditioned taste aversions illustrates
preparedness.
Classical Conditioning Is
Selective
• Animals are biologically prepared to learn
conditioned taste aversions
• Taste aversions can occur with only one
pairing of the taste of a tainted food and
later illness.
Reasons Taste Aversion Is
Unique
• Taste aversion only requires one pairing of
the NS with the US.
• Several hours can occur between the
presentation of the NS and the US and the
association between the two stimuli will
occur.
OPERANT CONDITIONING
Learning By Consequences
Thorndike’s Law of Effect
• Behavior consistently rewarded will
become learned behavior.
• Contemporary psychologists refer to this
as the principle of reinforcement
Operant Conditioning
• We learn to
associate a
response and its
consequence
• Key to learning
trained behavior
that doesn’t begin
naturally within an
organism
– Ex. Pigeon flapping
its wings or pecking
for food
Operant Conditioning
• Operant (O.C.):
– behaviors are emitted (in the presence of
specific stimuli) to earn rewards or avoid
punishments
• The behavior is more likely or less likely to
occur based on its consequences.
• B. F. Skinner modified Pavlov’s concept and
Thorndike’s law of effect.
• Skinner used reinforcement
and punishment to enhance
learning.
Operant/Instrumental Conditioning
• Operant or instrumental conditioning is learning
to make or withhold a certain response because
of its consequences.
• Operant behaviors are different from the
responses involved in classical conditioning
– They are voluntarily emitted
– Those involved in classical conditioning are
elicited by stimuli.
Operant Conditioning: Shaping
• Shaping: procedure in which reinforcers guide
behavior closer and closer approximations of a
desired goal
– The organism is learning associations between its
behavior and resulting events
– Ex.
Operant Conditioning Terms
• Reinforcer:
– An event or stimulus that makes the behavior
it follows more likely to occur again.
– Best when not delayed but immediately
following the behavior
Types of Reinforcement
•
•
•
•
Primary reinforcers
Secondary reinforcers
Positive reinforcers
Negative reinforcers
A Closer Look At Reinforcement
• Primary reinforcer:
– A reinforcer that is rewarding in itself, such as
food, water, and sex.
• Secondary reinforcer:
– A reinforcer that acquires its reinforcing power
through association with a primary reinforcer.
– Money: #1 secondary reinforcer
A Closer Look At Reinforcement
• Positive reinforcer:
– A pleasant event that follows an operant
response and increases the likelihood that the
response will recur.
• Negative reinforcer: strengthens a given
response by removing an aversive stimuli.
Operant Conditioning Terms
• Punishment: Any event that decreases the
likelihood that the behavior preceding it will
occur again.
Skinner’s Box
Chamber containing a bar or a key that an animal
can manipulate to obtain a reward
SKINNER BOX
Secondary
reinforcer
Primary
reinforcer
punishment
Secondary
reinforcer
Primary
reinforcer
What Is Punishment?
• The aim of punishment is to decrease the
likelihood that an ongoing behavior will
recur.
• Punishment must be swift, sufficient, and
certain for it to be effective.
A Closer Look at Punishment
• Punishment is generally not as effective as
the skillful application of reinforcement.
• Avoidance training is an alternative
strategy to using punishment.
• Avoidance training:
– Learning a desirable behavior to prevent the
occurrence of something unpleasant.
Negative side effects of
punishment
• Slows down learning; punishing for errors
• May suppress good behavior too; why
should I try at all
• Cat’s away syndrome
• I’m a bad person
• Only training method used only training
method learned; cyclical effect
• Unfortunate effect on the punisher
Reinforcement vs. Punishment
• Reinforcement increases the rate of
responding.
• Punishment decreases the rate of
responding.
Two Major Types of
Reinforcement
•
•
•
•
Interval: time/clock: 7am-12pm-6pm
Ratio: amount: 1:1, 2:1, 3:1
Schedules can be:
Continuous:
– each response is reinforced and thus learned
more quickly but not as long lasting
• Intermittent/partial:
– reinforcement does not follow every response
but the behavior lasts longer
Schedules of Reinforcement
• Intermittent reinforcement: stronger schedule
– Reinforcement which rewards are given for some
correct responses but not for every one;
– This generates behavior that persists longer than
behavior learned by continuous reinforcement and
thus is more resistant to extinction (behavior no
longer occurs).
• Partial reinforcement encourages learners to keep
"testing" for a reward.
• The type of partial reinforcement schedule also matters.
Schedules of Reinforcement
Interval Schedules
• A fixed-interval schedule:
– Reinforcement given for the first correct
response after a fixed time period, tends to
result in a flurry of responding right before a
reward is due.
• A variable-interval schedule:
– Reinforces the first correct response after an
unpredictable period of time, tends to result in
a slow but steady pattern of responding as the
learner keeps testing for the next payoff.
Schedules of Reinforcement
Ratio Schedules
• A fixed-ratio schedule:
– behavior is rewarded after a fixed number of
correct responses,
– so the result is usually a high rate of
responding because faster responses yield
quicker payoffs.
Schedules of Reinforcement
• A variable-ratio schedule:
– Provides reinforcement after a varying
number of correct responses.
– Encourages a high rate of response that is
especially persistent because the person
keeps harboring the hope that the next
response will bring a reward.
Examples of Schedules
• Continuous reinforcement:
– Putting money in a parking meter to avoid a
parking ticket
• Fixed-ratio schedule:
– Being paid for producing a specific number of
items (as in a factory setting)
Examples of Schedules
• Variable-ratio schedule:
– Playing a slot machine
• Fixed-interval schedule:
– Receiving a salary paycheck every two weeks
• Variable-interval schedule:
– Surprise quizzes
Other Types of Learning
•
•
•
•
•
•
•
Cognitive learning
Learned Helplessness
Latent learning
Cognitive maps
Insight
Learning sets
Social learning theory
Learned Helplessness
• Failure to take steps to avoid or escape
from an unpleasant or aversive stimulus
that occurs as a result of previous
exposure to unavoidable painful stimuli.
Cognitive Learning
• Cognitive learning:
– Learning that depends on mental processes
that are not directly observable
• Latent learning:
– Learning that is not immediately reflected in a
behavioral change
– Occurs once there is incentive to demonstrate
the behavior
Cognitive Learning
• Extrinsic motivation: a desire to perform a
behavior due to promised rewards or threats of
punishment
• Intrinsic motivation: a desire to perform a
behavior for its own sake and to be effective
– Bribing people to do this they already enjoy doing will
reduce their level of intrinsic motivation
Cognitive Learning
• Cognitive map:
– A learned mental
image of a spatial
environment that
may be called on
to solve problems
when stimuli in the
environment
change.
Insight Learning
• Insight:
– Learning that occurs rapidly as a result of
understanding all the elements of a problem.
Learning Sets
• The ability to become increasingly more
effective in solving problems as more
problems are solved.
– i.e., “learning how to learn”
Social Learning Theory
• A view of learning that
emphasizes the ability to
learn by observing or
witnessing/imitating a
model or receiving
instructions, without
firsthand experience by
the observer.
• Observational learning:
Albert Bandura
Social Learning Theory
• Modeling: the process of observing and imitating
a specific behavior
– Ex. Little brother wearing his hat like older brother
– Ex. Bandura’s research on aggression
– Ex. Prosocial behavior: positive, constructive, an
helpful behavior
• Mirror neurons: frontal lobe neurons that fire
when performing certain actions or when
observing another doing so.
– Has to do with learning language as well
Practice Test
1. In __________ reinforcement, the reinforcer follows
every correct response.
a. intermittent
b. partial
c. negative
d. continuous
2. In Pavlov's experiments with dogs, salivation was the
a. conditioned response.
b. unconditioned stimulus.
c. conditioned stimulus.
d. unconditioned response.
3. The presentation of an aversive stimulus or the removal of
a positive stimulus are both examples of
a. negative reinforcement.
b. punishment.
c. positive reinforcement.
d. secondary reinforcement.
4. In classical conditioning, learning is evident when a
a. stimulus automatically produces a response without a prior
history of experience.
b. stimulus which did not initially produce a response now
elicits that response.
c. spontaneously emitted response increases in frequency as
a result of its consequences.
d. subject repeats an action he or she has observed in another
and is praised for it.
5. In Thorndike's law of effect, events critical for
conditioning
a. occur after the response.
b. occur before the response.
c. occur simultaneously with the response.
d. are unrelated to the response except during extinction.
6. If you have a snake phobia because you once heard a
loud noise while looking at a snake, for you a snake is
a(n)
a. US.
b. CS.
c. UR.
d. CR.
7. A series of responses that gradually approach a desired
pattern of behavior are called
a. adaptations.
b. gradients.
c. successive approximations.
d. conditioning trials.
8. If the conditioned stimulus is presented many times
without reinforcement, we can expect
a. an increase in stimulus generalization.
b. the strength of the UR to increase.
c. an increase in response generalization.
d. extinction to occur.
9. A child has learned to avoid a furry, black cat. However,
she still plays with her grandmother's short-haired tabby.
Her response demonstrates
a. negative transfer.
b. extinction.
c. discrimination.
d. successive approximation.
10. Punishment is most effective in suppressing behavior
when it is
a. immediate, consistent, and intense.
b. delayed, consistent, and mild.
c. immediate, consistent, and mild.
d. delayed, inconsistent, and intense.