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Chapter Seven
Learning: The Role of Experience
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Learning
 Learning: a relatively enduring change in
an organism’s behavior or capabilities
 Four basic learning processes:
 Habituation
 Classical conditioning
 Operant conditioning
 Observational learning
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Learning
 Behaviorism:
 Assumes that there are laws of learning
that apply to virtually all organisms
 Learning is explained in terms of directly
observable events
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Adapting to the Environment
 Personal adaptation: focuses on how an
organism’s behavior changes in response
to environmental stimuli
 Habituation: a decrease in the strength of
response to a repeated stimulus
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Classical Conditioning
 Classical conditioning: a process in which
an organism learns to associate two
stimuli
 One stimulus elicits a response that originally
was elicited only by the other stimulus
 Process was discovered by Ivan Pavlov while
studying the salivation response in dogs
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Classical Conditioning
 Acquisition: the period during which a
response is being learned
 Neutral stimulus: a stimulus that does
not naturally elicit a response in an
organism
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Classical Conditioning
 Unconditioned stimulus (UCS): elicits
an innate response (the UCR) without
prior learning
 Unconditioned response (UCR): an
innate response that is elicited by a
stimulus (the UCS) without prior
learning
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Classical Conditioning
 Conditioned stimulus (CS): a stimulus that,
through association with a UCS, comes to
elicit a conditioned response similar to the
original UCR
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Classical Conditioning
 Conditioned response (CR): a response
elicited by a conditioned stimulus
 Conditioning typically occurs over the
course of many pairings, but it can happen
in a single trial in certain cases
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Classical Conditioning
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Classical Conditioning
 Forward short-delay pairing: CS appears
first and is still present when the UCS
appears
 Forward trace pairing: the CS appears and
then disappears, and then the UCS is
presented 2-3 seconds later
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Classical Conditioning
 Simultaneous pairing: the CS and the UCS
are presented at the same time
 Backward pairing: the CS is presented
after the UCS
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Classical Conditioning
 Classical conditioning is strongest when:
 There are repeated CS-UCS pairings
 The UCS is more intense
 The sequence involves forward pairing
 The time interval between the CS and UCS is
short
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Classical Conditioning
 Extinction: the CS is presented repeatedly
in the absence of the UCS, causing the
CR to weaken and eventually disappear
 Spontaneous recovery: the reappearance
of a previously extinguished CR after a
rest period and without new learning trials
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Classical Conditioning
 Stimulus generalization: stimuli similar to the
initial CS elicit a CR
 Example: salivation may be elicited by a bell or a piano
tone
 Discrimination: a CR occurs in the presence of
one stimulus but not others
 Example: salivation may not be elicited by a whistle
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Classical Conditioning
 Higher-order conditioning: occurs when a
neutral stimulus becomes a CS after being
paired with an already established CS
 Produces a CR that is weaker and
extinguishes more rapidly than the original CR
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Classical Conditioning
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Classical Conditioning
 Acquiring and overcoming fear:
 John B. Watson conditioned an 11-month-old
boy, Albert, to be afraid of white rats
 Unconditioned stimulus: loud noises
 Fear generalized to other white, furry objects
 Albert was never “fixed”
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Classical Conditioning
 Behavioral therapies based on classical
conditioning are very effective for treating
phobias
 Exposure therapies: a patient is exposed to a
stimulus (CS) that arouses an anxiety
response without the presence of a UCS,
allowing extinction to occur
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Classical Conditioning
 Systematic desensitization: patients learn
muscle-relaxation techniques and then are
gradually exposed to fear-provoking
stimuli
 Aversion therapy: conditions an aversion
to a stimulus that triggers unwanted
behavior by pairing it with a noxious UCS
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Classical Conditioning
 Classical conditioning is often used by
advertisers to influence our attitudes
toward products
 Allergic reactions: classical conditioning
can be used to elicit an allergic reaction to
a previously neutral stimulus
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Classical Conditioning
 Anticipatory nausea and vomiting (ANV):
developed by many chemotherapy
patients in anticipation of a treatment
session
 Immune system can be classically
conditioned, affecting susceptibility to
disease and fatal illness
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Operant Conditioning
 Thorndike’s Law of Effect:
 Instrumental learning: the process by
which animals utilize trial and error to
achieve a desired outcome
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Operant Conditioning
 Thorndike’s Law of Effect:
 A response followed by a satisfying
consequence will be more likely to occur
 A response followed by an annoying
consequence will become less likely to occur
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Operant Conditioning
 Operant conditioning: behavior is
influenced by the consequences that
follow it
 Skinner Box: a special chamber used to
study operant conditioning
 Box contains a lever on one wall
 A food pellet is released when the lever is
pressed
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Operant Conditioning
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Operant Conditioning
 Reinforcement: a response is
strengthened by an outcome that follows it
 Reinforcer: the outcome (a stimulus or event)
that increases the frequency of a response
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Operant Conditioning
 Punishment: a response is weakened by
an outcome that follows it
 Punisher: a consequence that weakens
(decreases) the frequency of a response
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Operant Conditioning
 Skinner’s analysis of operant behavior:
 A: antecedents of behavior
 B: behaviors
 C: consequences that follow behavior
IF A is present
AND B is emitted
THEN C will occur
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Operant Conditioning
 Distinguishing operant from classical
conditioning:
 Classical: Behavior changes are due to the
association of two stimuli (CS-UCS) presented
prior to the response (CR)
 Focuses on elicited behaviors
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Operant Conditioning
 Distinguishing operant from classical
conditioning:
 Operant: Behavior changes as the result of
the consequences that follow it (reinforcement
or punishment)
 Focuses on emitted behaviors
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Operant Conditioning
 Discriminative stimulus: a signal that a
particular response will now produce
certain consequences
 Example: a light in the Skinner Box may
indicate whether or not food will be dispensed
when the lever is pressed
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Operant Conditioning
 Positive reinforcement: occurs when a
response is strengthened by the
presentation of a stimulus
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Operant Conditioning
 Primary reinforcers: stimuli that are
naturally reinforcing because they satisfy
biological needs
 Secondary reinforcers: stimuli that acquire
reinforcing properties through their
association with primary reinforcers
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Operant Conditioning
 Negative reinforcement: occurs when a
response is strengthened by the removal
(or avoidance) of an aversive stimulus
 Negative reinforcer: the aversive stimulus that
is removed or avoided
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Operant Conditioning
 “Positive” and “negative” refer to
presentation or removal of a stimulus, not
“good” and “bad”
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Operant Conditioning
 Operant extinction: the weakening and
eventual disappearance of a response
because it is no longer reinforced
 Resistance to extinction: the degree to which
nonreinforced responses persist
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Operant Conditioning
 Aversive / positive punishment: occurs
when a response is weakened by the
presentation of a stimulus
 Negative punishment / response cost:
occurs when a response is weakened by
the removal of a stimulus
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Operant Conditioning
 Problems with punishment:
 Suppresses behavior; does not provide an
acceptable alternative
 May arouse negative emotions
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Operant Conditioning
 Effective punishment:
 Must occur after every transgression
 Must be immediate
 Must be intense
 Must not be signaled by discriminative
stimulus
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Operant Conditioning
 Shaping: reinforcing successive
approximations toward a final response
 Chaining: develops a sequence of
responses by reinforcing each response
with the opportunity to perform the next
response
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Operant Conditioning
 Operant generalization: an operant
response occurs to a new antecedent
stimulus or situation that is similar to the
original one
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Operant Conditioning
 Operant discrimination: an operant
response will occur to one antecedent
stimulus but not to another
 Stimulus control: a behavior that is
influenced by discriminative stimuli
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Schedules of Reinforcement
 Continuous reinforcement: every response
of a particular type is reinforced
 Example: a rat receives food every time a
lever is pressed
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Schedules of Reinforcement
 Partial (intermittent) reinforcement: only a
portion of the responses of a particular
type are reinforced
 Example: a slot machine
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Schedules of Reinforcement
 Ratio schedule: a certain percentage of
responses are reinforced
 Example: 50% of the rat’s lever presses are
reinforced with food
 Based on number of responses
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Schedules of Reinforcement
 Interval schedule: a certain amount of time
must elapse between reinforcements,
regardless of how many responses occur
 Based on the passage of time
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Schedules of Reinforcement
 Fixed schedule: reinforcement occurs after
a fixed number of responses or after a
fixed time interval
 Variable schedule: the required number of
responses or the time interval varies at
random around an average
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Schedules of Reinforcement
 Fixed ratio
schedule:
reinforcement is
given after a fixed
number of
responses
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Schedules of Reinforcement
 Variable ratio
schedule:
reinforcement is
given after a
variable number of
responses, all
centered around an
average
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Schedules of Reinforcement
 Fixed interval
schedule: the first
response that
occurs after a fixed
time interval is
reinforced
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Schedules of Reinforcement
 Variable interval
schedule:
reinforcement is
given for the first
response that
occurs after a
variable time
interval, centered
around an average
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Schedules of Reinforcement
 Continuous reinforcement produces more
rapid learning than partial reinforcement
 The association between a behavior and its
consequences is easier to understand
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Schedules of Reinforcement
 Continuously reinforced responses
extinguish more rapidly than partially
reinforced responses
 The shift to no reinforcement is sudden and
easier to understand
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Escape and Avoidance
 Escape conditioning: the organism learns
a response to terminate an aversive
stimulus
 Acquired and maintained through negative
reinforcement
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Escape and Avoidance
 Avoidance conditioning: the organism
learns a response to avoid an aversive
stimulus
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Escape and Avoidance
 Two-factor theory of avoidance learning:
both classical and operant conditioning are
involved in avoidance learning
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Operant Conditioning
 Applications for education and workplace:
 Teaching machines (Skinner) and computer-
assisted instruction
 Immediate performance feedback
 Self-paced learning
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Operant Conditioning
 Applications for education and workplace:
 Token economies: desirable behaviors are
quickly reinforced with tokens that are later
turned in for other reinforcers
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Operant Conditioning
 Applications for specialized animal
training:
 Assist people with disabilities
 Police / Military training
 Entertainment industry
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Operant Conditioning
 Applications for modifying problem
behaviors:
 Applied behavior analysis: combines a
behavioral approach with the scientific method
to solve individual and societal problems
 Designs and implements a program of
change
 Collects data on the program’s effectiveness
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Operant Conditioning
 Applications for modifying problem
behaviors:
 Behavior modification: procedures used to
change behavior
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Using Operant Principles
 Modifying behavior:
 Specify the problem
 Collect baseline data
 Identify the antecedents and consequences
 Develop a plan to modify the antecedents and
consequences
 Implement the program and measure progress
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Crossroads of Conditioning
 Biological constraints:
 Preparedness: through evolution, animals are
biologically predisposed to learn some
associations more easily than others
 Behaviors related to a species’ survival are
learned more easily
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Crossroads of Conditioning
 Conditioned taste aversion: a conditioned
response in which the taste, sight, and/or
smell of a particular food becomes
disgusting and repulsive
 Conditioned taste aversions and conditioned
fear are both influenced by biological
preparedness
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Crossroads of Conditioning
 Garcia & Koelling, 1966:
 When paired with nausea, sweet water easily
became a CS (but lights and sounds did not)
 When paired with electric shock, lights and
sounds easily became a CS (but sweet water
did not)
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Crossroads of Conditioning
 Biological preparedness in humans:
 Seligman (1971): humans are biologically
prepared to acquire certain fears more readily
than others
 Easier to condition a fear of snakes and
spiders than a fear of flowers
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Crossroads of Conditioning
 Instinctive drift: the tendency for a
conditioned response to drift back toward
instinctive behavior
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Cognition and Conditioning
 S-R (stimulus-response) psychology:
learning involves the relatively automatic
formation of bonds between a stimulus
and a response
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Cognition and Conditioning
 S-O-R (cognitive) model of learning: the
organism’s cognitive representation of the
world (O) falls between the stimulus and
the response
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Cognition and Conditioning
 Insight: the sudden perception of a useful
relationship that helps to solve a problem
 Challenges ideas about trial-and-error learning
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Cognition and Conditioning
 Cognitive map: a mental representation of
a spatial layout
 Suggests that learning provides knowledge
and an expectation of “what leads to what”
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Cognition and Conditioning
 Expectancy model: the most important
factor in classical conditioning is how well
the CS predicts (signals) the appearance
of the UCS
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Cognition and Conditioning
 The role of awareness:
 Organisms develop an awareness of the
relations between their responses and the
probable consequences
 The best predictor of behavior is the perceived
contingency between stimulus and response
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Cognition and Conditioning
 Latent learning:
learning that
occurs but is not
demonstrated until
later, when there is
an incentive to
perform
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Observational Learning
 Observational learning: occurs by
observing the behavior of a model
 Modeling: humans’ capacity to learn by
observation
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Observational Learning
 Social-cognitive theory: people learn by
observing the behavior of models and
acquiring the belief that they can produce
behaviors to influence the events in their
lives
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Observational Learning
 The modeling process:
 Attention: we must pay attention to the
model’s behavior
 Retention: we must retain that information in
memory so that it can be recalled when
needed
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Observational Learning
 The modeling process:
 Reproduction: we must be physically capable
of reproducing the model’s behavior
 Motivation: we must be motivated to display
the behavior
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Observational Learning
 Self-efficacy: people’s belief that they
have the capability to perform behaviors
that will produce a desired outcome
 Bandura’s (1965) “Bobo Doll” experiment
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Observational Learning
 Viewing media violence:
 Decreases viewers’ concerns about the
suffering of victims
 Habituates us to the sight of violence
 Provides aggressive models
 Viewing prosocial behavior enhances
people’s helping behavior
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Observational Learning
 Applications of observational learning:
 Learning academic and sports-related skills
 Enhancing prosocial behavior
 Addressing global social problems (literacy,
AIDS)
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The Adaptive Brain
 Learning involves multiple brain regions
and neural circuits
 Hypothalamus and dopamine pathways
regulate our ability to experience reward
 Cerebellum plays a role in acquiring classically
conditioned movements
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The Adaptive Brain
 Learning involves multiple brain regions
and neural circuits
 Amygdala plays a role in acquiring conditioned
fears
 Frontal lobes become less involved as we gain
experience at novel tasks
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The Adaptive Brain
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