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Learning Unit - Myers
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LEARNINGCHP. 8
LearningLearning• Learning
–relatively permanent change in an organism’s behavior due to experience
–experience (nurture) is the key to learning
AssociationAssociation• We learn by association
– Our minds naturally connect events that occur in sequence
– Aristotle 2000 years ago– John Locke and David Hume 200 yrs ago
• Associative Learning– learning that two events occur together
• two stimuli• a response and its consequences
AssociationAssociation
• Learning to associate two events
Event 1 Event 2
Sea snail associates splash with a tail shock
Seal learns to expect a snack for its showy antics
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• We learn to associate two stimuli
Two related events:
Lightning
Stimulus 1
Thunder
Stimulus 2
Result after repetition
We see lightning
Stimulus
We wince anticipatingthunder
Response
Operant ConditioningOperant Conditioning
• We learn to associate a response and its consequence
Response: Pushingvending machine button
Consequence: Receiving a candy bar
BehaviorismBehaviorism•John B. Watson
– viewed psychology as objective science•generally agreed-upon consensus today
– recommended study of behavior without reference to unobservable mental processes•not universally accepted by all schools of thought today
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Ivan Pavlov – 1849-1936– Russian physician/
neurophysiologist– Nobel Prize in 1904– studied digestive secretions
Pavlov’s Classic Experiment
Pavlov’s Classic Experiment
Before Conditioning
During Conditioning After Conditioning
UCS (foodin mouth)
Neutralstimulus(tone)
Nosalivation
UCR (salivation)
Neutralstimulus(tone)
UCS (foodin mouth)
UCR(salivation)
CS(tone)
CR (salivation)
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Pavlov’s device for recording salivation
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Classical Conditioning– organism comes to associate two
stimuli•lightning and thunder•tone and food
– begins with a reflex– a neutral stimulus is paired with a
stimulus that evokes the reflex– neutral stimulus eventually comes to
evoke the reflex
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Unconditioned Stimulus (UCS)– effective stimulus that unconditionally-
automatically and naturally- triggers a response
• Unconditioned Response (UCR)– unlearned, naturally occurring
automatic response to the unconditioned stimulus•salivation when food is in the mouth
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Conditioned Stimulus (CS)– previously neutral stimulus that, after
association with an unconditioned stimulus, comes to trigger a conditioned response
• Conditioned Response (CR)– learned response to a previously neutral
conditioned stimulus
ConditioningConditioning• Acquisition
– the initial stage of learning, during which a response is established and gradually strengthened
– in classical conditioning, the phase in which a stimulus comes to evoke a conditioned response
– in operant conditioning, the strengthening of a reinforced response
ConditioningConditioning• Extinction
– diminishing of a CR – in classical conditioning, when a UCS does
not follow a CS– in operant conditioning, when a response is
no longer reinforced
Classical or Pavlovian Conditioning
Strengthof CR
Pause
Acquisition(CS+UCS)
Extinction(CS alone)
Extinction(CS alone)
Spontaneousrecovery ofCR
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Spontaneous Recovery– reappearance, after a rest period, of
an extinguished CR
• Generalization– tendency for a stimuli similar to CS
to evoke similar responses
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
• Discrimination– in classical conditioning, the ability to
distinguish between a CS and other stimuli that do not signal and UCS
– in operant conditioning, responding differently to stimuli that signal a behavior will be reinforced or will not be reinforced
GeneralizationGeneralizationDrops of salivain 30 seconds
60
50
40
30
20
10
0Hindpaw
Pelvis Shoulder Frontpaw
Thigh Trunk Foreleg
Part of body stimulated
Classical or Pavlovian Conditioning
Classical or Pavlovian Conditioning
UCS(passionate kiss) UCR
(sexualarousal)
CS(onionbreath)
CS(onion breath) CR
(sexualarousal)
UCS(passionate Kiss) UCR
(sexualarousal)
Nausea Conditioning in Cancer Patients
Nausea Conditioning in Cancer Patients
UCS(drug)
UCR(nausea)
CS(waiting room)
CS(waitingroom) CR
(nausea)
UCS(drug)
UCR(nausea)
Operant ConditioningOperant Conditioning• Operant Conditioning
– type of learning in which behavior is strengthened if followed by reinforcement or diminished if followed by punishment
• Law of Effect– Thorndike’s principle that behaviors
followed by favorable consequences become more likely and behaviors followed by unfavorable consequences become less likely
Operant ConditioningOperant Conditioning• Operant Behavior
– complex or voluntary behaviors•push button, perform complex task
– operates (acts) on environment– produces consequences
• Respondent Behavior– occurs as an automatic response to
stimulus– behavior learned through classical
conditioning
Operant ConditioningOperant Conditioning
• B.F. Skinner (1904-1990)– elaborated Thorndike’s Law of
Effect– developed behavioral
technology
Operant ChamberOperant Chamber
• Skinner Box– soundproof
chamber with a bar or key that an animal presses or pecks to release a food or water reward
– contains a device to record responses
Was Deborah a lab rat?Was Deborah a lab rat?
Operant ConditioningOperant Conditioning
• Reinforcer– any event that strengthens the behavior it
follows
• Shaping– conditioning procedure in which reinforcers
guide behavior toward closer approximations of a desired goal
• Successive Approximations– reward behaviors that increasingly resemble
desired behavior
Principles of ReinforcementPrinciples of
Reinforcement• Primary Reinforcer
– innately reinforcing stimulus– satisfies a biological need
• Secondary Reinforcer– conditioned reinforcer– learned through association with primary
reinforcer
Schedules of ReinforcementSchedules of
Reinforcement• Continuous Reinforcement
– reinforcing the desired response each time it occurs
– learning occurs rapidly– extinction occurs rapidly
• Partial Reinforcement – reinforcing a response only part of the
time– results in slower acquisition– greater resistance to extinction
Schedules of ReinforcementSchedules of
Reinforcement
• Fixed Ratio (FR)– reinforces a response only after a
specified number of responses– faster you respond the more
rewards you get– different ratios– very high rate of responding– like piecework pay
Schedules of ReinforcementSchedules of
Reinforcement•Variable Ratio (VR)
– reinforces a response after an unpredictable number of responses
–average ratios– like gambling, fishing–very hard to extinguish because of unpredictability
Schedules of ReinforcementSchedules of
Reinforcement• Fixed Interval (FI)
– reinforces a response only after a specified time has elapsed
– response occurs more frequently as the anticipated time for reward draws near
Schedules of ReinforcementSchedules of
Reinforcement
• Variable Interval (VI)– reinforces a response at
unpredictable time intervals– produces slow steady responding– like pop quiz
Schedules of ReinforcementSchedules of
Reinforcement
Variable Interval
Number of responses
1000
750
500
250
010 20 30 40 50 60 70
Time (minutes)
Fixed Ratio
Variable Ratio
Fixed Interval
Steady responding
Rapid respondingnear time forreinforcement
80
PunishmentPunishment• Punishment
– aversive event that decreases the behavior that it follows
– powerful controller of unwanted behavior
Problems with Punishment
Problems with Punishment
• Punished behavior is not forgotten, it's suppressed- behavior returns when punishment is no longer eminent
• Causes increased aggression- shows that aggression is a way to cope with problems- Explains why aggressive delinquents and abusive parents come from abusive homes
Problems with Punishment
Problems with Punishment• Creates fear that can generalize to
desirable behaviors, e.g. fear of school, learned helplessness, depression
• Does not necessarily guide toward desired behavior- reinforcement tells you what to do--punishment tells you what not to do- Combination of punishment and reward can be more effective than punishment alone
• Punishment teaches how to avoid it
Neg. Reinforcement vs Punishment
Neg. Reinforcement vs Punishment
STIMULUS TYPE
SUPPLY A STIMULUS
REMOVE A STIMULUS
Appetitive Stimulus (Something Desired)
Aversive Stimulus (Something not
desired)
Positive Reinforcement Time Out
PunishmentNegative Reinforce
ment
Operant vs Classical Conditioning
Operant vs Classical Conditioning
Extinction CR decreases when CS is Responding decreases whenrepeatedly presented alone. reinforcement stops.
Classical Conditioning
OperantConditioning
The Response Involuntary, automatic “Voluntary,” operates on environment
Acquisition Associating events; Associating response with aCS announces UCS. Consequence (reinforcer or
punisher).
Cognitive Subjects develop expectation Subjects develop expectation that processes that CS signals the arrival of a response will be reinforced or
UCS. Punished; they also exhibit latentlearning, without reinforcement
Biological Natural predispositions Organisms best learn behaviors predispositions contain what stimuli and similar to their natural behaviors;
responses can easily be unnatural behaviors instinctivelyassociated. drift back toward natural ones.
Cognition and Operant Conditioning
Cognition and Operant Conditioning
• Cognitive Map– mental representation of the layout of one’s
environment– example- after exploring a maze, rats act
as if they have learned a cognitive map of it
• Latent Learning– learning that occurs, but is not apparent
until there is an incentive to demonstrate it• Ex.
Cognition and Operant Conditioning
Cognition and Operant Conditioning
• Overjustification Effect– the effect of promising a reward for
doing what one already likes to do– the person may now see the reward,
rather than intrinsic interest, as the motivation for performing the task
Mindful LearningMindful LearningImportance of cognitive process**
Mindfulness - actively engaged in the present, sensitive to new things**increased competence, improved memory, fewer accidents
Mindlessness - programmed to act according to the sense our behavior made in the past
3 myths on ability to learn3 myths on ability to learn
1. Basics should be learned so well they become second nature
2. To pay attention to something we should hold it still and focus on it
3. It is important to learn how to delay gratification
Observational LearningObservational Learning• Observational Learning
– learning by observing and imitating others
• Modeling– process of observing and imitating
behavior
• Prosocial Behavior– positive, constructive, helpful behavior– opposite of antisocial behavior
Albert BanduraAlbert Bandura
• Influenced by Watson, Pavlov, & Skinner
• Theories blend of environmental influences with information processing(brain) & being shaped by the social situation
• Bobo doll experiment• Overcoming phobias
The Adaptive BrainThe Adaptive Brain
• Discuss behavior using 3 components:– Biological (DNA/Hormones)– Psychological (mind & how we process
information) – Environmental (factors outside of
ourselves)
• No simple answer for what makes us “tick”
Can you explain the supermarket tantrum?
Can you explain the supermarket tantrum?
• What behaviors maintain those tantrums?
• What behavioral principals would work best in extinguishing tantrum behaviors?
Group Assignment/Review “Treatment Plan”
Group Assignment/Review “Treatment Plan”
• A smoking cessation module for heavy smokers• A procrastination-prevention module for high
school AP students• A treatment module for aviatophobics (fear of
flying)• An anxiety-reducing module for young children
who fear going to dentist (dentophobia); or• A treatment module for compulsive shoppers who
are mired in credit-card debtsInclude as many of the following terms/concepts as possible:habituation, classical conditioning, acquisition, extinction,
stimulus generalization, discrimination, operant conditioning, reinforcement, punishment, reward, response cost, delay of gratification, shaping, token economy, modeling