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1. Gazzaniga Heatherton Halpern Psychological Science FOURTH
EDITION Chapter 6 Learning 2013 W. W. Norton & Company,
Inc.
2. Learning B. F. Skinner, who was inspired by the work of
Watson and Pavlov, has been one of the most influential people in
contemporary psychology Skinner believed that, to be scientists,
psychologists had to study observable actions and focus on the
behaviors people and nonhuman animals display
3. 6.1 What Ideas Guide the Study of Learning? Define classical
conditioning. Differentiate between US, UR, CS, and CR. Describe
the role of learning in the development and treatment of phobias
and drug addiction. Discuss the evolutionary significance of
classical conditioning. Describe the Rescorla-Wagner model of
classical conditioning.
4. 6.1 What Ideas Guide the Study of Learning? Skinner and
other behaviorists dismissed the importance of introspection and
mental states in favor of basic learning principles and scientific
approaches to psychology. Learning theories have been used to
improve quality of life and to train humans and nonhuman animals to
learn new tasks.
5. Learning Results from Experience Learning: a relatively
enduring change in behavior, resulting from experience Associations
develop through conditioning, a process in which environmental
stimuli and behavioral responses become connected classical
(Pavlovian) conditioning: learning that two types of events occur
together operant (instrumental) conditioning: learning that a
behavior leads to a particular outcome
6. Learning Results from Experience Learning Theory arose in
the early twentieth century in response to Freudian and
introspective approaches John B. Watson argued that only observable
behavior was a valid indicator of psychological activity, and that
the infant mind was a tabula rasa, or blank slate He stated that
the environment and its effects were the sole determinants of
learning Behaviorism was the dominant paradigm into the 1960s, and
had a huge influence on every area of psychology
7. Behavioral Responses Are Conditioned Watson was influenced
by Ivan Pavlovs research on the salivary reflex, an automatic
response when food stimulus is presented to a hungry animal Pavlov
noticed the dogs salivated as soon as they saw the bowls that
usually contained food, suggesting a learnedresponse Twitmyer made
a similar observation of the kneejerk reflex in humans: when paired
with a bell, subjects can be conditioned to demonstrate the
knee-jerk response without other triggers
8. Pavlovs Experiments Classical (Pavlovian) conditioning: A
neutral object comes to elicit a response when it is associated
with a stimulus that already produces that response A typical
Pavlovian experiment involves: Conditioning trials: neutral
stimulus AND unconditioned stimulus are paired to produce reflex,
e.g. salivation Neutral stimulus: anything the animal can see or
hear as long as it is NOT associated with the reflex being tested,
e.g. ringing bell Unconditioned stimulus (US): a stimulus that
elicits a response, such as a reflex, without any prior learning,
e.g. food Critical trials: neutral stimulus alone is tested, and
effect on the reflex is measured
9. Terminology of Pavlovs Experiments Unconditioned response
(UR): a response that does not have to be learned, such as a reflex
Unconditioned stimulus (US): a stimulus that elicits a response,
such as a reflex, without any prior learning Conditioned stimulus
(CS): a stimulus that elicits a response only after learning has
taken place Conditioned response (CR): a response to a conditioned
stimulus; a response that has been learned Can you think of any
learned associations that have classically conditioned you?
10. Acquisition, Extinction, and Spontaneous Recovery Pavlov
was influenced by Darwinand believed that conditioning is the basis
of adaptive behaviors Acquisition: the gradual formation of an
association between the CS and US The critical element in the
acquisition of a learned association is time, or contiguity The CR
is stronger when there is a very brief delay between the CS and the
US For example, scary music begins to play right before a
frightening scene in a movienot during or after
11. Acquisition, Extinction, and Spontaneous Recovery How long
do learned behaviors persist? Animals must learn when associations
are no longer adaptive extinction: a form of learning that the
prior association no longer holds. The CR is weakened when the CS
is repeated without the US, and eventually extinguishes Spontaneous
recovery: a previously extinguished response reemerges after the
presentation of the CS The recovery will fade unless the CS is
again paired with the US Extinction inhibits the associative bond,
but does not eliminate it
12. Generalization, Discrimination, and Second Order
Conditioning In a learning situation, how does the brain determine
which stimulus is relevant? stimulus generalization: responding to
stimuli that are similar but not identical to the CS produce the CR
stimulus discrimination: a differentiation between two similar
stimuli when only one of them is consistently associated with the
US Second-order conditioning: a CS becomes associated with other
stimuli associated with the US. This phenomenon helps account for
the complexity of learned associations
13. Phobias and Addictions Have Learned Components Classical
conditioning helps explain many behavioral phenomena. Among the
examples are phobias and addictions.
14. Phobias and Their Treatment Phobia: an acquired fear out of
proportion to the real threat of an object or of a situation Fear
conditioning: the process of classically conditioning animals to
fear neutral objects The responses include specific physiological
and behavioral reactions freezing: may be a hardwired response to
fear that helps animals deal with predators
15. Phobias and their Treatment In 1919, John B. Watson became
one of the first researchers to demonstrate the role of classical
conditioning in the development of phobias by devising the Little
Albert experiment At the time, the prominent theory of phobias
wasbased on Freudian ideas about unconscious repressed sexual
desires Watson proposed that phobias could be explained by simple
learning principles, such as classical conditioning
16. Phobias and their Treatment The Little Albert Research
Method: Little Albert was presented with neutral objects (a white
rat and costume masks) that provoked a neutral response During
conditioning trials, when Albert reached for the white rat (CS) a
loud clanging sound (US) scared him (UR) Results: Eventually, the
pairing of the rat (CS) and the clanging sound (US) led to the rats
producing fear (CR) on its own. The fear response generalized to
other stimuli presented with the rat initially, such as the costume
masks Conclusion: Classical conditioning can cause people to fear
neutral objects
17. Phobias and their Treatment Watson planned to conduct
extinction trials to remove the learned phobias but Alberts mother
removed him from the study Do you think this type of research is
ethical? Watsons colleague, Mary Cover Jones, used classic
conditioning techniques to develop effective behavioral therapies
to treat phobias Counterconditioning exposing a patient to small
doses of the feared stimulus while they engage in an enjoyable
task
18. Phobias and their Treatment Systematic desensitization:a
formal treatment based on counterconditioning Developed by
behavioral therapist Joseph Wolpe in 1997 CS CR1 (fear) connection
can be broken by developing a CS CR2 (relaxation) connection
Psychologists now believe that exposure to the feared stimulus is
more important than relaxation
19. Drug Addiction Classical conditioning also plays an
important role in drug addiction. Environmental cues associated
with drug use can induce conditioned cravings Unsatisfied cravings
may result in withdrawal, an unpleasant state of tension and
anxiety, coupled with changes in heart rate and blood pressure The
sight of drug cues leads to activation of the prefrontal cortex and
various regions of the limbic system and produces an expectation
that the drug high will follow
20. Drug Addiction Psychologist Shepard Siegel (2005) believed
exposing addicts to drug cues was an important part of treating
addiction Exposure helps extinguish responses to the cues and
prevents them from triggering cravings Siegel and his colleagues
conducted research into the relationship between drug tolerance and
situation The body has learned to expect the drug in that location
and compensates by altering neurochemistry or physiology to
metabolize it Conversely, if addicts take their usual large doses
in novel settings, they are more likely to overdose because their
bodies will not respond sufficiently to compensate
21. Classical Conditioning Involves More Than Events Occurring
at the Same Time Pavlovs original explanation for classical
conditioning was that any two events presented in contiguity would
produce a learned association Pavlov and his followers believed
that the associations strength was determined by factors such as
the intensity of the conditioned and unconditioned stimuli However,
in the mid-1960s, a number of challenges to Pavlovs theory
suggested that some conditioned stimuli were more likely than
others to produce learning Contiguity was not sufficient to create
CS-US associations
22. Evolutionary Significance Psychologist John Garcia and
colleagues showed that certain pairings of stimuli are more likely
to become associated than others conditioned food aversion:the
association between eating a food and getting sick Response occurs
even if the illness was caused by a virus or some other condition
Especially likely to occur if the food was not part of the persons
usual diet. A food aversion can be formed in one trial Animals that
associate a certain flavor with illness, and therefore avoid that
flavor, are more likely to survive and pass along their genes
23. Evolutionary Significance Learned adaptive responses may
reflect the survival value that different auditory and visual
stimuli have based on potential dangers associated with the stimuli
What evolutionary value do you see in this learned behavior?
Biological preparedness: Psychologist Martin Seligman (1970) argued
that animals are genetically programmed to fear specific objects
People are predisposed to wariness of outgroup members (Olsson,
Ebert, Banaji, & Phelps, 2005)
24. Learning Involves Cognition Classical conditioning is a way
that animals come to predict the occurrence of eventswhich prompted
psychologists to take a cognitive perspective on learning Robert
Rescorla argued that for learning to take place, the conditioned
stimulus must accurately predict the unconditioned stimulus
Rescorla-Wagner model: states that the strength of the CS-US
association is determined by the extent to which the unconditioned
stimulus is unexpected or surprising
25. Learning Involves Cognition Other aspects of classical
conditioning consistent with the Rescorla-Wagner model: Orienting
response: occurs when an animal encounters a novel stimulus
Blocking effect: once a conditioned stimulus is learned, it can
prevent the acquisition of a new conditioned stimulus Occasion
setter: a stimulus associated with a CS that acts as a trigger for
the CS
26. Critical Thinking Skill: Avoiding the Association of Events
with Other Events That Occur at the Same Time People, and
apparently other animals, have a strong need to understand what
causes or predicts events. Their resulting associations can lead
people to cling to superstitions What misfortunes could actually
occur in the situations shown on the following slide?
27. 6.2 How Does Operant Conditioning Differ from Classical
Conditioning? Define operant conditioning. Distinguish between
positive reinforcement, negative reinforcement, positive
punishment, and negative punishment. Distinguish between schedules
of reinforcement. Identify biological and cognitive factors that
influence operant conditioning.
28. 6.2 How Does Operant Conditioning Differ from Classical
Conditioning? Operant (instrumental) conditioning: a learning
process in which the consequences of an action determine the
likelihood that it will be performed in the future B. F. Skinner
chose the term operant to express the idea that animals operate on
their environments to produce effects. Edward Thorndike performed
the first reported carefully controlled experiments in comparative
animal psychology using a puzzle box. Law of Effect: Any behavior
that leads to a satisfying state of affairs is likely to occur
again, and any behavior that leads to an annoying state of affairs
is less likely to occur again.
29. Reinforcement Increases Behavior Thirty years after
Thorndike, Skinner developed a more formal learning theory based on
the law of effect He objected to the subjective aspects of
Thorndikes law of effect: States of satisfaction are not observable
empirically Skinner believed that behavior occurs because it has
been reinforced reinforcer: a stimulus that follows a response and
increases the likelihood that the response will be repeated
30. The Skinner Box An operant chamber that allowed repeated
conditioning trials without requiring interaction from the
experimenter Contained one lever connected to a food supply and
another connected to a water supply
31. Shaping Sometimes animals take a long time to perform the
precise desired action. What can be done? Shaping: an
operant-conditioning technique that consists of reinforcing
behaviors that are increasingly similar to the desired behavior
successive approximations: anybehavior that even slightly resembles
the desired behavior Suppose you wanted to teach yourself to do
something. Which behavior would you choose, and how would you go
about shaping it?
32. Reinforcers Can Be Conditioned primary reinforcers: satisfy
biological needs such as food or water secondary reinforcers:
events or objects established through classical conditioning that
serve as reinforcers but do not satisfy biological needs, e.g.
money or compliments
33. Reinforcer Potency David Premack theorized about how a
reinforcers value could be determined The key is the amount of time
an organism, when free to do anything, engages in a specific
behavior associated with the reinforcer Premack principle: Using a
more valued activity can reinforce the performance of a less valued
activity How do you think you could use this principle on
yourself?
34. Both Reinforcement and Punishment Can Be Positive or
Negative Reinforcement and punishment have the opposite effects on
behavior Reinforcement increases a behaviors probability Punishment
decreases its probability Both reinforcement and punishment can be
positive or negative This designation depends on whether something
is given or removed, not on whether any part of the process is good
or bad
35. Positive and Negative Reinforcement Reinforcement positive
or negative increases the likelihood of a behavior positive
reinforcement: the administration of a stimulus to increase the
probability of a behaviors being repeated, e.g. a reward negative
reinforcement: the removal of a stimulus to increase the
probability of a behaviors being repeated, e.g. requiring a rat to
press a lever to turn off a shock
36. Positive and Negative Punishment Punishment reduces the
probability that a behavior will recur positive punishment: the
administration of a stimulus to decrease the probability of a
behaviors recurring, e.g. receiving a ticket for speeding negative
punishment: the removal of a stimulus to decrease the probability
of a behaviors recurring, e.g. taking away driving privileges for
bad behavior
37. Effectiveness of Parental Punishment For punishment to be
effective, it must be reasonable, unpleasant, and applied
immediately so that the relationship between the unwanted behavior
and the punishment is clear How might this go wrong? Punishment
often fails to offset the reinforcing aspects of the undesired
behavior Research indicates that physical punishment is often
ineffective, compared with grounding and time-outs Many
psychologists believe that positive reinforcement is the most
effective way of increasing desired behaviors while encouraging
positive parent/child bonding
38. Operant Conditioning is Influenced by Schedules of
Reinforcement How often should reinforcers be given? continuous
reinforcement: a type of learning in which behavior is reinforced
each time it occurs partial reinforcement: a type of learning
inwhich behavior is reinforced intermittently Partial
reinforcements effect on conditioning depends on the reinforcement
schedule
39. Ratio and Interval Schedules Partial reinforcement can be
administered according to either the number of behavioral responses
or the passage of time ratio schedule: Reinforcement is based on
the number of times the behavior occurs interval schedule:
Reinforcement is provided after a specific unit of time Ratio
reinforcement generally leads to greater responding than does
interval reinforcement
40. Fixed and Variable Schedules Partial reinforcement can also
be given on a fixed schedule or a variable schedule fixed schedule:
Reinforcement is provided after a specific number of occurrences or
after a specific amount of time variable schedule: Reinforcement is
provided at different rates or at different times
41. Behavioral Persistence Continuous reinforcement is highly
effective for teaching a behavior. If the reinforcement is stopped,
however, the behavior extinguishes quickly variable-ratio schedule:
persistent behavior thatonly sometimesresults in reward
partial-reinforcement extinction effect: Behavior is more
persistent under partial reinforcement than under continuous
reinforcement Can this explain why gambling is so addictive?
42. Psychology: Knowledge You Can Use Can Behavior Modification
Help Me Stick with an Exercise Program? Consider these steps:
Identify a behavior you wish to change Set goals Monitor your
behavior Select a reinforcer and decide on a reinforcement schedule
Reinforce the desired behavior Modify your goals, reinforcements,
or reinforcement schedules, as needed
43. Behavior Modification Behavior modification: the use of
operantconditioning techniques to eliminate unwanted behaviors and
replace them withdesirable ones Token economies operate on the
principle of secondary reinforcement. Tokens are earned for
completing tasks and lost for bad behavior. Tokens can later be
traded for objects or privileges
44. Biology and Cognition Influence Operant Conditioning
Behaviorists such as Skinner believed that all behavior could be
explained by straightforward conditioning principles However, a
great deal about behavior remains unexplained Biology constrains
learning, and reinforcement does not always have to be present for
learning to take place
45. Biological Constraints Animals have a hard time learning
behaviors that run counter to their evolutionary adaptation Marian
and Keller Breland used operant-conditioning techniques to train
animals but ran into difficulty when the tasks were incompatible
with innate adaptive behaviors Conditioning is most effective when
the association between the response and the reinforcement is
similar to the animals built-in predispositions For example, Bolles
argued that animals have built-in defense reactions to threatening
stimuli
46. Acquisition/Performance Distinction Tolman argued that
learning can take place without reinforcement latent learning:
takes place in the absence of reinforcement insight learning: A
solution suddenly emerges after either a period of inaction or of
contemplation Tolmans studies involved rats running through mazes
cognitive map: a visual/spatial mental representation of an
environment The presence of reinforcement does not adequately
explain insight learning, but it helps determine whether the
behavior is subsequently repeated
47. 6.3 Does Watching Others Affect Learning? Describe the
concept of the meme. Define observational learning. Generate
examples of observational learning, modeling, and vicarious
learning. Discuss contemporary evidence regarding the role of
mirror neurons in learning.
48. 6.3 Does Watching Others Affect Learning? Teaching someone
to perform a complex task requires more than reinforcing arbitrary
correct behaviors. We learn many behaviors, including attitudes,
through observation.
49. Learning Can Be Passed On through Cultural Transmission
Meme: a unit of knowledge transmitted within a culture Memes can be
conditioned through association or reinforcement, but are often
learned by watching the behavior of other people Through social
learning, some behaviors are passed along from one generation to
the next
50. Learning Can Occur through Observation and Imitation
Observational learning: the acquisition or modification of a
behavior after exposure to at least one performance of that
behavior Observational learning is a powerful adaptive tool for
humans and other animals Can you think of some examples of
observational learning in animals?
51. Banduras Observational Studies Banduras studies suggest
that exposing children to violence may encourage them to act
aggressively
52. Media and Violence The extent to which media violence
impacts aggressive behavior in children is debated Some studies
demonstrate desensitization to violence after exposure to violent
video games However, it is difficult to draw the line between
playful and aggressive behaviors in children There may be
extraneous variables that affect both TV habits AND violent
tendencies Based on what you have just learned, how might media
impact behavior?
53. Social Learning of Fear Susan Mineka noticed that
lab-reared monkeys were not afraid of snakes the way monkeys in the
wild are Her research demonstrated that animals fears can be
learned through observation Social forces play a role in
fear-learning in humans too
54. Demonstration and Imitation modeling: the imitation of
behavior through observational learning Modeling is effective only
if the observer is physically capable of imitating the behavior
Imitation is much less common in nonhuman animals than in humans
Adolescents who associate smoking with admirable figures are more
likely to begin smoking
55. Vicarious Reinforcement vicarious learning: learning the
consequences of an action by watching others being rewarded or
punished for performing the action A key distinction in learning is
between the acquisition of a behavior and its performance In other
words, learning a behavior does not necessarily lead to performing
that behavior
56. Mirror Neurons What happens in the brain during imitation
learning? mirror neurons: neurons that are activated when one
observes another individual engaging in an action and when one
performs the action that was observed May serve as the basis of
imitation learning, but the firing of mirror neurons does not
always lead to imitative behavior May be the neural basis for
empathy and play a role in humans ability to communicate through
language Debatable if brain activity reflects prior learning rather
than imitation
57. 6.4 What Is the Biological Basis of Learning? Discuss the
role of dopamine and the nucleus accumbens in the experience of
reinforcement. Define habituation, sensitization, and longterm
potentiation. Describe the neural basis of habituation,
sensitization, long-term potentiation, and fear conditioning.
58. 6.4 What Is the Biological Basis of Learning? When animals
and people learn, what changes in the brain? Researchers are
rapidly identifying the neurophysiological basis of learning.
Similar brain activity occurs for most rewarding experiences.
59. Dopamine Activity Underlies Reinforcement Positive
reinforcement works in two ways: provides the subjective experience
of pleasure increases wanting for the object or event that produced
the reward The neurotransmitter dopamine is involved in addictive
behavior and plays an important role in reinforcement
60. Pleasure Centers intracranial self-stimulation:
self-administered shock to pleasure centers of the brain Starving
rats prefer ICSS to food over 80 percent of the time The neural
mechanisms underlying both ICSS and natural reward appear to use
the same neurotransmitter: dopamine This suggests dopamine serves
as the neurochemical basis of positive reinforcement in operant
conditioning Interfering with dopamine eliminates self-stimulation
as well as naturally motivated behaviors
61. Dopamine and Reward The nucleus accumbens is a subcortical
brain region that is part of the limbic system More dopamine is
released under deprived conditions than under nondeprivedconditions
Do you have the intuition that food tastes better when you are
hungry? In operant conditioning, dopamine release sets the value of
a reinforcer, and blocking dopamine decreases reinforcement
Dopamine blockers are can also help people with Tourettes syndrome
regulate their involuntary body movements Robinson and Berridge
(1993) introduced an important distinction between the wanting and
liking aspects of reward For example, a smoker may want a cigarette
but not especially enjoy it Dopamine appears to be especially
important in wanting a reward
62. Secondary Reinforcers Also Rely on Dopamine Natural
reinforcers appear to signal dopamine reward directly Secondary
reinforcers at first fail to trigger dopamine release but may do so
readily after they are paired with unconditioned stimuli Money is a
secondary reinforcer that activates dopamine systems
63. Habituation and Sensitization Are Simple Models of Learning
Kandels work on the aplysia has shown that habituation and
sensitization, two simple forms of learning, occur through
alteration in neurotransmitter release habituation: a decrease in
behavioral response after repeated exposure to a nonthreatening
stimulus sensitization: an increase in behavioral response after
exposure to a threatening stimulus
64. Long Term Potential Is a Candidate for the Neural Basis of
Learning long-term potentiation (LTP): the strengthening of a
synaptic connection, making the postsynaptic neurons more easily
activated Through LTP, intense stimulation of neurons strengthens
synapses, increasing the likelihood that one neurons activation
will increase the firing of other neurons LTP effects are most
easily observed in brain sites known to be involved in learning and
memory, such as the hippocampus Research has also supported Hebbs
rule that neurons that fire together wire together
65. LTP and the NMDA Receptor LTP occurs when NMDA receptors
are stimulated by nearby neurons Joseph Tsien modified genes in
mice to make the genes NMDA receptors more efficient Tseins Doogie
Mice learned novel tasks quicker and showed increased fear
conditioning
66. Fear Conditioning LTP in the amygdala appears to play a
role in fear conditioning Joseph LeDouxs research suggests that
fearconditioning might produce long-lasting learning through the
induction of LTP Heightened activity in the amygdala, when subjects
watched another persons distress, suggests that similar mechanisms
are involved in conditioned and observational fear learning