Psychology, 8th Edition (Myers) Chapter 8 – Learning Much of what

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Psychology, 8th Edition (Myers)
Chapter 8 – Learning
Much of what we do, we learn from experience.
Adaptability – our capacity to learn new behaviors that enable us to cope with changing circumstances
Learning – a relatively permanent change in an organism’s behavior due to experience
How Do We Learn?
 Associative learning – learning that certain events occur together
o Classical conditioning – associating two stimuli
o Operant conditioning – associating a response and its consequence (continue acts with positive
consequences, avoid acts that elicit negative consequences)
 Observational learning – learning by watching others
Classical Conditioning
 Behaviorism – the view that psychology should be an objective science that studies behavior without
reference to mental processes
o most current behavioral psychologists would argue that mental processes should be studied
 Classical conditioning – type of learning in which an organism comes to associate stimuli; also called
Pavlovian or respondent conditioning
o Unconditioned stimulus (US) – a stimulus that naturally and automatically triggers a response.
o Unconditioned response (UR) – the unlearned, naturally occurring response to the
unconditioned stimulus (US), such as salivation when food is in the mouth.
o Conditioned stimulus (CS) – an originally irrelevant stimulus that, after association with an
unconditioned stimulus (US), comes to trigger a conditioned response (CR)
o Conditioned response (CR) – the learned response to a previously neutral, but now conditioned,
stimulus (CS)
 Ivan Pavlov’s experiment – studied how dogs associate salivation with food
o US – food
o UR – salivation to food
o CS – tone by tuning fork
o CR – salivation to tone
 Another example – an experimenter sounds a tone just before delivering an air puff to your eye
o US – air puff
o UR – eye blink to air puff
o CS – tone
o CR – eye blink to tone
 Acquisition – the initial stage in classical conditioning; the phase associating a neutral stimulus with an
unconditioned stimulus so that the neutral stimulus comes to elicit a conditioned response. In operant
conditioning, the strengthening of a reinforced response.
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


o In Pavlov’s experiment, the acquisition phase occurred when he paired the neutral stimulus
(tuning fork) with the unconditioned stimulus (food)
Extinction – the diminishing of a conditioned response; in classical conditioning it is when the US does
not follow a CS; in operant conditioning it is when a response is no longer reinforced.
o Pavlov found that when he rang the fork repeatedly without presenting the food, the dogs
salivated less and less
Spontaneous recovery – the reappearance, after a pause, of an extinguished conditional response.
o Pavlov found that if he waited a few hours before ringing the fork again, the dogs would salivate
to the ringing after the pause.
Generalization – the tendency, once a response has been conditioned, for stimuli similar to the
conditioned stimulus to elicit a similar response.
o Pavlov found that dogs would salivate to tones of different pitches that they had not previously
associated with food.
Discrimination – in classical conditioning, the learned ability to distinguish between a conditioned
stimulus and stimuli that do not signal an unconditioned response.
o Pavlov’s dogs also learned to respond to certain tones and not to others
Extending Pavlov’s Theory
 Pavlov and Watson underestimated the importance of cognitive processes and biological constraints on
an organism’s capacity to learn
 Cognitive Processes
o In classical conditioning, human and other animals can learn when to expect or predict stimuli,
and the awareness can weaken associations.
 Biological Predispositions
o Each species is biological predisposed to learning certain associations  those that enhance
survival.
Pavlov’s Legacy
 Classical conditioning is a learning technique that virtually all organism’s use to adapt to their
environments
 Pavlov showed that learning processes can be studied objectively (by observing behaviors)
Applications of Classical Conditioning
 Watson – Little Albert conditioned to fear white rats; later generalized to a fear of fluffy white animals
 Classical conditioning can be helpful in treatment programs for substance abuse, phobias, etc
Operant Conditioning
 Operant conditioning – learning in which behaviors are strengthened if followed by a reinforcer or
diminished if followed by a punisher.
 Respondent behavior – behavior that occurs as an automatic response to some stimulus (Skinner’s term
for behavior learned through classical conditioning)
 Operant behavior – behavior that operates on the environment, producing consequences
 How to determine between classical and operant conditioning…
o Classical  “Is the organism learning associations between events that it doesn’t control?”
o Operant  “Is the organism learning associations between its behavior and resulting events?”
Skinner’s Experiments
 B.F. Skinner – behavioral psychologist
o Elaborated on Thorndike’s Law of Effect – rewarded behavior is likely to reoccur, punished
behavior is likely to diminish
o Operant chamber – aka Skinner Box; contained a bar or key that an animal can manipulate to
obtain a food or water reinforce, with attached devices to record the animal’s rate of bar pressing
or key pecking (first used with rats, later pigeons)
Shaping Behavior
 Skinner used shaping – an operant conditioning procedure in which reinforcers guide behavior toward
closer and closer approximations of the desired behavior.
o Ex: you want a rat to push a lever. You might start rewarding the rat every time it came near the
lever. As it approached the lever, you would reward it only when it got closer and closer. Then
start rewarding it when it touched the lever. Then start rewarding it when it pushed the lever.
Types of Reinforcers
 Reinforcer – any event that strengthens the behavior it follows
o Loosely deemed a “reward” but can be any consequence that increases the likelihood of a
behavior happening again.
o Reinforcers vary with circumstances and subject  what reinforcers might reproduce behavior
in one person may not work with another
o Big Bang Theory - Sheldon trains Penny with positive reinforcement
(http://m.youtube.com/#/watch?v=qy_mIEnnlF4&desktop_uri=%2Fwatch%3Fv%3Dqy_mIEnnl
F4)
Reinforcement
Positive Reinforcement
Description
Addition of a desirable stimulus
Negative Reinforcement
Removal of an undesirable stimulus
Example
Getting a hug, receiving praise, receiving a
paycheck
Fastening seatbelt to turn off car beeping, no
homework for good behavior, taking Aspirin
to relieve a headache
***Reinforcement (positive or negative) STRENGTHENS behavior.
*** When you see the term positive, always think about ADDING something.
*** When you see the term negative, always think about REMOVING something.
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Primary reinforcers – an innately reinforcing stimulus, such as one that satisfies a biological need
o Receiving food, being relieved of an electric shock
Conditioned reinforcers – aka secondary reinforcer; a stimulus that gains its reinforcing power through
its association with a primary reinforcer
o If a rat in a Skinner box learns that a light reliably signals that food is coming, the rat will work
to turn on the light which becomes the conditioned reinforcer.
o Money, good grades, pleasant tone of voice, praise  learned to associate these with basic needs
Immediate and Delayed Reinforcers
 Rats typically did not respond to reinforcers that were delayed after the desired behavior
 Humans respond well to delayed reinforcers (paycheck, grades, trophies  all reinforcers that are given
after a period of time during which the behavior is not as reinforced.
 Studies with 4 year olds and candy have revealed that they have trouble understanding the gratification
that can come with a delayed reinforcement… some would chose to have candy immediately even when
told that if they waited until the next day, they would receive more candy  understanding of delayed
reinforcers signals maturity (Kids and marshmallows  http://www.youtube.com/watch?v=amsqeYOk-w)
 Mature adults sometimes chose small but immediate consequences at the expense of bigger but delayed
consequences
o Late night tv at the expense of tomorrow’s sluggishness
o Drug use for an immediate high at the expense of a later crash and diminished health
Reinforcement Schedules
Reinforcement
Schedule
Continuous
reinforcement
Partial or
Intermittent
Reinforcement reinforcing a
response only
part of the time;
results in slower
acquisition of a
response but
much greater
resistance to
extinction that
does continuous
reinforcement
Fixed-ratio
Variable-ratio
Fixed-interval
Variable-interval
Description
Reinforcing the desired
response every time it occurs;
typically used at the
beginning of an operant
conditioning process
Reinforces a response only
after a set/certain number of
responses
Reinforces a response after
varying/unpredictable
numbers of responses
Reinforces behavior only after
a certain amount of time has
passed
Reinforces behavior after
varying/unpredictable time
intervals
Example
Parent gives child praise or
gives a piece of candy every
time they use the bathroom
during the potty-training
process
People paid on piecework
(every 30 pieces),
Slot-machines
Weekly paychecks, waiting for
pudding/Jell-O to set
Pop quizzes, your boss
checking your work randomly
Punishment
 Punishment – an event that decreases the behavior it follows
Punishment
Description
Example
Adding (administering) an
Spanking, yelling at a child, a traffic ticket,
Positive Punishment
undesirable stimulus
giving homework
Removing (withdrawal) a desirable
Time-out at recess, revoked driver’s license
Negative Punishment
stimulus
***Punishment (positive or negative) DECREASES behavior.
*** When you see the term positive, always think about ADDING something.
*** When you see the term negative, always think about REMOVING something.
Positive
Reinforcement Adding a desired
stimulus
Adding an undesired
Punishment
stimulus
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

Negative
Removing an
undesired stimulus
Removing a desired
stimulus
Children who receive physical punishment tend to display more aggression
Is punishment effective or does it diminish behaviors in certain environments?
Punishment may extinguish a behavior but it often does not lead to desirable behavior.
Punishment often teaches how to avoid it… psychologists emphasize the importance of reinforcement
instead.
Extending Skinner’s Understanding
 Cognition and Operant Conditioning
o Latent learning – learning that occurs but is not apparent until there is an incentive to
demonstrate it.
o Cognitive map – a mental representation of the layout of one’s environment
o Rats have shown the development of a cognitive map while navigating a maze. Once a reward is
placed at the end of the maze, the rats complete the maze much faster.
o Children may learn from their parents, but not demonstrate the learning until later.
o There is more to learning than behaviors and consequences
o The type of motivation can affect the effectiveness of reinforcements and punishments
 Intrinsic motivation – the desire to perform a behavior for its own sake.
 Extrinsic motivation – the desire to perform a behavior due to promised rewards or
threats of punishment.
 Children who were normally avid readers (intrinsically motivated) were paid for reading
and their reading amount decreased  positive reinforcement backfired
 Biological Predispositions
o Attempts to condition organisms with an operant technique will only be successful if the
consequences are appropriate for the organism.
 Ex: you can train a rat easily with food but training a human adult with food alone would
be nearly impossible
Skinner’s Legacy
 Skinner adamantly refused to acknowledge that influence of cognitive processes (thoughts and feelings)
held any power in shaping behaviors.
 Critics argued that ignoring mental processes dehumanized people and neglected their personal freedom
and free will.
Applications of Operant Conditioning
 School
o Feedback (reinforcement, punishment) must be immediate and then students must be pointed in
the right direction for the next step.
 Sports
o Shaping behavior to create good technique and mastery at each level.
 Work
o Performance goals must be well-defined and achievable
o Reward specific behaviors
o Practice immediate reinforcement
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Home
o
o
o
o
Give children attention and reinforcement when they are behaving well
Target specific behavior to reward
Ignore whining
Do not spank/hit children for punishment
Contrasting Classical and Operant Conditioning
 Both associative learning
 Both involve acquisition, extinction, spontaneous recovery, generalization, and discrimination
 Procedural differences
o Classical conditioning – an organism associates different stimuli that it does not control and
responds automatically (respondent behavior)
o Operant conditioning – an organism associates its operant behaviors (those that act on its
environment to produce rewarding or punishing stimuli) with their consequences which either
strengthen or weaken the behavior’s future occurrence.
COMPARING CLASSICAL AND OPERANT CONDITIOING
CLASSICAL
OPERANT
Response
Involuntary, automatic
Voluntary, operates on environment
Acquisition
Associating events; CS announces US
Associating response with a consequence
(reinforce or punisher)
Extinction
CR decreases when CS is repeatedly
Responding decreases when reinforcement
presented alone
stops
Cognitive
Organisms develop expectation that CS
Organisms develop expectations that a response
processes
signals the arrival of US
will be reinforced or punished; they also exhibit
latent learning, without reinforcement
Biological
Natural predispositions constrain what
Organisms best learn behaviors similar to their
predispositions stimuli and responses can easily be
natural behaviors; unnatural behaviors
associated
instinctively drift back toward natural ones.
Learning by Observing
 Among higher mammals, learning does not only occur through experience.
 Observational learning – learning by observing others
o Ex: a child who witnesses their big sister burn their fingers on the stove will learn not to put their
fingers on the stove even though they didn’t experience the consequence directly.
 Modeling – the process of observing and imitating a specific behavior
 Mirror neurons - frontal lobe neurons that fire when performing certain actions or when observing
another doing so.
o help in the acquisition of language by showing children how to form words with their lips and
tongue
o helps in empathy (feeling sympathy for others)
o Children are very affected by shaping and modeling and reflect behaviors quickly
Bandura's Experiment
 Experimental group of preschoolers was exposed to an adult beating a blow-up (Bobo) doll for 10
minutes and then left to see if they would do the same  children exposed to aggressive adult models
were more likely to be aggressive towards the doll when alone with the toys
 We are more likely to mimic someone we see as similar to ourselves, as successful, or as admirable.
Applications of Observational Learning
 Antisocial models may have antisocial effects (family, TV, movies, friends)
 Helps us understand why children with abusive parents are more likely to abuse their children  it is
hard to unlearn lessons we learned as children
Positive Observational Learning
 Prosocial behavior (positive, constructive, helpful) can have prosocial effects
o Liberty Mutual Commercial - Helping Hands are Contagious
(http://www.youtube.com/watch?v=frpp6DjCaJU)
 Models are more effective when their actions and words are consistent not hypocritical  children can
mimic both
Television and Observational Learning
 Violent TV/movies can desensitize children and adults to pain, death, and punishment
 Violent viewing correlates with violent play/actions
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