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Operant ConditioningOperant Conditioning
Thomas G. Bowers, Ph.D.Thomas G. Bowers, Ph.D.
Penn State HarrisburgPenn State Harrisburg
Operant ConditioningOperant Conditioning
Thought to operate upon the Thought to operate upon the environmentenvironment
So-called “voluntary behavior” So-called “voluntary behavior” Thorndike aimed to explain goal Thorndike aimed to explain goal
directed behaviordirected behavior– Developed Law of EffectDeveloped Law of Effect
Law of EffectLaw of Effect
Behavior is sensitive to its Behavior is sensitive to its consequencesconsequences
Positive reinforcement - Positive reinforcement - Pleasurable consequences stamp Pleasurable consequences stamp in the behaviorin the behavior
Punishment - Unpleasant events Punishment - Unpleasant events stamp out the behaviorstamp out the behavior
Behavior-consequence Behavior-consequence RelationshipRelationship
Positive reinforcement acts to Positive reinforcement acts to increase the probability of increase the probability of behaviorbehavior
Punishment acts to decrease the Punishment acts to decrease the probability of behaviorprobability of behavior
Behavior-consequence Behavior-consequence RelationshipRelationship
Negative reinforcement (or Negative reinforcement (or escape) acts to increase behavior escape) acts to increase behavior which eliminates or removes the which eliminates or removes the negative stimulusnegative stimulus
Omission removal of a positive Omission removal of a positive stimulus decreases behavior stimulus decreases behavior
Response-consequence Response-consequence Relationships Relationships
PositiveReinforcement
Punishment
Omission Escape orAvoidance
Response
Stimulus
Conditioning and Conditioning and ExtinctionExtinction
Responses are developed by a Responses are developed by a shaping process of successive shaping process of successive approximationsapproximations
Extinction refers to the cessation Extinction refers to the cessation of reinforcementof reinforcement
Behavioral UnitsBehavioral Units
Time
Response/Min
•Acquisition Extinction
Contingency LearningContingency Learning
P(Sr/No Res)
P(Sr/R)
1.0
.01.0
Operant Contingency Operant Contingency SpaceSpace
Reinforcement has a contingent Reinforcement has a contingent effect, increasing behavior, while effect, increasing behavior, while punishment or even non-punishment or even non-reinforcement will decrease behaviorreinforcement will decrease behavior
When reinforcement and responses When reinforcement and responses are independent, or noncontingent, are independent, or noncontingent, then learned helplessness resultsthen learned helplessness results
Operant Contingency Operant Contingency SpaceSpace
Learned helplessness resembles Learned helplessness resembles depressiondepression
Seligman developed the paradigmSeligman developed the paradigm Leads to a global failure to initiate Leads to a global failure to initiate
behaviorbehavior Associated with depletion of Associated with depletion of
monoamine neurotransmitters monoamine neurotransmitters
Operant ConditioningOperant Conditioning
What is learned?What is learned? R - S relationship?R - S relationship? How can something temporally How can something temporally
remote (i.e. following) cause an remote (i.e. following) cause an event?event?
Some theorists emphasize S - R Some theorists emphasize S - R relationshipsrelationships
Avoidance BehaviorAvoidance Behavior
Much of our day to day behavior Much of our day to day behavior may serve to avoid negative or may serve to avoid negative or aversive stimuli or consequencesaversive stimuli or consequences
Signaled avoidance trialsSignaled avoidance trials– Early training does not avoidance, but Early training does not avoidance, but
escapes the stimulusescapes the stimulus– Latency tends to decreaseLatency tends to decrease
Avoidance BehaviorAvoidance Behavior
Shock postponement procedureShock postponement procedure– Also called free-operant avoidanceAlso called free-operant avoidance– Sidman avoidanceSidman avoidance
Most animals manage to learn this Most animals manage to learn this well, with few actual shocks well, with few actual shocks experiencedexperienced
Theories of AvoidanceTheories of Avoidance
Does the animal “know”?Does the animal “know”?
Theories of AvoidanceTheories of Avoidance
Two factor theory - MowrerTwo factor theory - Mowrer– Initial learning by reinforcement of Initial learning by reinforcement of
escape behavior escape behavior – Classical conditioning also occurring, Classical conditioning also occurring,
and CS acquires fear eliciting and CS acquires fear eliciting propertiesproperties
– Response here is reinforced by fear Response here is reinforced by fear (CS) removal(CS) removal
– Avoidance behavior resultsAvoidance behavior results
Theories of AvoidanceTheories of Avoidance
Tests to inhibitory procedures Tests to inhibitory procedures appear to confirm predictionsappear to confirm predictions
Some problems, thoughSome problems, though– animals will respond reliably even if animals will respond reliably even if
only a reduction of shock frequency is only a reduction of shock frequency is the contingencythe contingency
– there is little evidence of conditioned there is little evidence of conditioned fear in well-trained animalsfear in well-trained animals
Theories of AvoidanceTheories of Avoidance
Some problems, thoughSome problems, though– avoidance of extinctionavoidance of extinction– avoidance can be extinguished, but avoidance can be extinguished, but
by response blockingby response blocking
Cognitive TheoriesCognitive Theories
Expectancy theoryExpectancy theory– Organism prefers no shock to shockOrganism prefers no shock to shock– Organism expects if it responds, no Organism expects if it responds, no
shock will occurshock will occur– Organism expects if it does not Organism expects if it does not
respond, shock will occurrespond, shock will occur– Expectancies are strengthened when Expectancies are strengthened when
confirmed, weakened when confirmed, weakened when disconfirmeddisconfirmed
Cognitive TheoriesCognitive Theories
Expectancy theoryExpectancy theory– Probability of avoidance increases as Probability of avoidance increases as
the degree of confirmation increasesthe degree of confirmation increases
Biological TheoriesBiological Theories
Bolles emphasized the adaptive Bolles emphasized the adaptive significance to persistent significance to persistent avoidance learningavoidance learning
Described a repertoire of defensive Described a repertoire of defensive reactionsreactions
Species-specific defensive Species-specific defensive reactions (SSDR)reactions (SSDR)
Biological TheoriesBiological Theories
Hierarchical organizationHierarchical organization Some patterns of responses are Some patterns of responses are
much easier to acquire than othersmuch easier to acquire than others
Conditioned Conditioned ReinforcementReinforcement
Neutral stimuli can also become a Neutral stimuli can also become a conditioned reinforcerconditioned reinforcer
Predictiveness, informativeness is Predictiveness, informativeness is important to becoming a important to becoming a secondary reinforcersecondary reinforcer
Animals will respond for the Animals will respond for the opportunity to gain informative opportunity to gain informative stimulus conditionsstimulus conditions
Applications of Secondary Applications of Secondary ReinforcementReinforcement
Token economiesToken economies– Common in our environmentCommon in our environment– Generalized secondary reinforcersGeneralized secondary reinforcers– FunctionsFunctions
Provide feedbackProvide feedback Provide information about what to do nextProvide information about what to do next Serve to bridge long gaps in Serve to bridge long gaps in
reinforcementreinforcement
– Economies now build in inflationEconomies now build in inflation