Myers’ PSYCHOLOGY
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Transcript of Myers’ PSYCHOLOGY
Myers’ PSYCHOLOGY
Chapter 8Learning
Learning Learning
relatively permanent change in an organism’s behavior due to experience
experience (nurture) is the key to learning
AssociationWe learn by association
Our minds naturally connect events that occur in sequence
Aristotle 2000 years ago John Locke and David Hume 200 yrs
agoAssociative Learning
learning that two events occur togethertwo stimulia response and its consequences
Association
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
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 Conditioning
We learn to associate a response and its consequence
Response: Pushingvending machine button
Consequence: Receiving a candy bar
BehaviorismJohn B. Watson
viewed psychology as objective sciencegenerally agreed-upon
consensus today recommended study of behavior
without reference to unobservable mental processesnot universally accepted by all
schools of thought today
Classical or Pavlovian Conditioning
Ivan Pavlov 1849-1936 Russian physician/
neurophysiologist Nobel Prize in 1904 studied digestive secretions
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
Pavlov’s device for recording salivation
Classical or Pavlovian ConditioningClassical Conditioning
organism comes to associate two stimulilightning and thundertone 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
Unconditioned Stimulus (UCS) effective stimulus that unconditionally-
automatically and naturally- triggers a response
Unconditioned Response (UCR) unlearned, naturally occurring
automatic response to the unconditioned stimulussalivation when food is in the mouth
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
ConditioningAcquisition
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
ConditioningExtinction
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
Spontaneous Recovery reappearance, after a rest
period, of an extinguished CRGeneralization
tendency for a stimuli similar to CS to evoke similar responses
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
GeneralizationDrops of salivain 30 seconds
60
50
40
30
20
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0Hindpaw
Pelvis Shoulder Frontpaw
Thigh Trunk Foreleg
Part of body stimulated
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
UCS(drug)
UCR(nausea)
CS(waiting room)
CS(waitingroom) CR
(nausea)
UCS(drug)
UCR(nausea)
Operant ConditioningOperant 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 Behavior
complex or voluntary behaviorspush 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 ConditioningB.F. Skinner (1904-1990)
elaborated Thorndike’s Law of Effect
developed behavioral technology
Operant ChamberSkinner 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
Operant ConditioningReinforcer
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 Reinforcement
Primary Reinforcer innately reinforcing stimulus satisfies a biological need
Secondary Reinforcer conditioned reinforcer learned through association with
primary reinforcer
Schedules of ReinforcementContinuous 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 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 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 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 Reinforcement
Variable Interval (VI) reinforces a response at
unpredictable time intervals produces slow steady responding like pop quiz
Schedules 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
Punishment
Punishment aversive event that
decreases the behavior that it follows
powerful controller of unwanted behavior
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 PunishmentCreates 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
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
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
Latent Learning
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 2202468
101214161820222426283032Average
errors
Days
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.
Observational Learning
Observational Learning learning by observing and imitating
othersModeling
process of observing and imitating behavior
Prosocial Behavior positive, constructive, helpful behavior opposite of antisocial behavior