Classical Conditioning Stimulus - - PowerPoint Presentation

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Classical ConditioningStimulus - sometimes that produces a reaction or a response from a person or animalClassic Conditioning - simple form of learning in which one stimulus (thought of food) response (salivating) usually calling forth another stimulus (actual food) occurs when 2 stimuli have been associated with EACH OTHER.Ivan Pavlov - 1849 - 1936 - Russian PsychologistDiscovered that dogs also learn to associate 1 thing with another when food is involved

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US - Unconditioned StimulusStimulus that causes a response that is automatic or reflexive reaction in an individualex. Loud noises, pin-prick, object rapidly approaching youUR - Unconditioned Response automatic responsebehavior that does not have to be learned as a response to a stimulus in the present situationex. Tensing the body in response to hearing a loud noise, jumping in response to being pricked by a pin, ducking in response to an object being thrown at you.Pavlov’s experimentUS = food; UR = dog’s salivation2

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CS - conditioned stimulusOriginally neutral stimulus—> learned stimulusCR - conditioned responselearned response to a stimulus that was previously meaningless or neutral.Think of CLASSIC CONDITIONING as “stimulus substitution”US is replaced by the CS and response stays about the same.The CR is the same as UR they are elicited by two different kinds of stimuliMust identify which kind of stimulus elicited the responseIf stimulus previously caused the response - USstimulus just learned = CS

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John WatsonInterested in how human emotions are learned Tested am 11 month old baby named ALBERTReactions to various stimuli white rat, rabbit, masks, balls of cottonAlbert’s response was positive and tried to touch when given a chanceWatson wanted to produce FEAR When ALBERT reached out to touch the rat (CS) Watson produced a loud noise (US) behind the child.Albert’s response was he CRIED (UR)

After

7x’s the sight of the rat (CS) caused ALBERT to cry (CR)

Albert conditioned to

ASSOCIATE

loud noise with 1 stimuli

– rat

Positive/Negative learned by Conditioning

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To understand how classical conditioning works need to identify basic principles:Acquisition - how fast you learn Interstimulus interval - time between CS ( bell) (sight of rat) + US (meat) (loud noise)Pavlov discovered timing was crucial of the CS. If CS was presented at the same time as the US , too long after it, too long before it, it had LITTLE or NO EFFECT on dog’s behavior****1st stimulus CS takes on the properties of the 2nd stimulus USExample : Medicine/HONEY6

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Extinction - elimination of a CR by presenting only the CS without the USex. Pavlov ringing bell without meat ; dog salivated less and stops salivatingUS = reinforcementExtinction occurs when reinforcement is withdrawn.EXAMPLE – GUINEA PIG7

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Spontaneous Recovery - reappearance of a CR after extinctionEXAMPLE - GUINEA PIGStimulus Generalization - act of responding in the same way to stimuli that seem to be similar even if the stimuli are not identicalex. Albert conditioned to fear RAT. He also cried when shown other furry objects - rabbit, mask of Santa Claus)CR (crying) was conditioned to the CS (rat) stimuli similar to the CS often became sufficient to elicit CRGreater similarity - stronger CR between stimuli8

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Stimulus Discrimination - responding differently to stimuli that are not similar to each other.Ex. Dog conditioned by bell–>stimulus generalization–> salivate in response to a metronome.If metronome never followed by US and bell always was , the CR to the metronome would stop to occur.Dog will discriminate between the two.9

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Conditioned Taste Aversion - learned avoidance of a particular food Taste aversion helps us avoid these foods by keeping us away from themEXAMPLE #5Kidney stone - USsevere stomach pain - URhamburger - CS stomach pain – CRConditioned taste aversion differs from regular classical condition in several respects:CTA occurs 1 trial requiring onlyOne pairing of the CS with the US instead of several

Interstimulus

interval for CTA can be hours rather than seconds.

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2 methods of reducing fears based on the principle of extinctionFlooding - person is exposed to the harmless stimulus until fear responses to the stimulus are extinguishedUsually effective—> Unpleasantex. Fear of heights - look out from 6 story window until not afraid Fear of snakes - put in a room with harmless snakes until not afraidCounterconditioning - pleasant stimulus is paired repeatedly with a fearful one, counteracting the fear.Systematic Desensitizationtaught relaxation techniques exposed to fear but try to relax ex. Fear of snakes

show picture of snake until can relax

next phase see a video until can relax

next show a real snake until can relax

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Operant Conditioning - learning strengthened when behavior is followed by positive reinforcementThorndike was observing Trial & Error learning.EXAMPLE – CATInstrumental conditioning - individual is instrumental in emitting, or producing a response.Thorndike proposed his LAW of EFFECT:Any response that produces satisfaction in a given situation becomes ASSOCIATED with that situation.

Situation

occurs again.

Response is more likely to be repeated.

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Thorndike - LAW OF EFFECTIf we do something and get rewarded we will do it againIf we do it often enough we will form a habitAcquisitionShaping effective to help subjects acquire or learn a behavior through operant conditioningExtinction Stronger original learning the longer you will continue to respondSpontaneous Recovery - occurrence of behavior that had been extinguished, can appear after a rest period.14

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BF SKINNER - named behavior = Operant ConditioningOperant behavior is first emitted more or less as a random act. Behavior becomes Learned or Operantly conditioned only when followed by regular reinforcement.Reinforcement usually REWARD.EXAMPLE – GLASSESShaping - successive approximationgradual process begins with reinforcement of some behavior that gets closer to the final behavior desired

Careful giving and withholding of reinforcement subject can gradually be made to perform complex responses

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Reinforcement - increases the probability that the behavior that precedes it will be repeatedMost effective if it is given immediately after a behaviorIf delayed - power is diminished. People prefer doing certain things more than others.EXAMPLE – CHILDPREMACK PRINCIPLEstates any 2 responses, the one that is more likely to occur can be used to reinforce the response that is less likely to occurExample Premack Principle

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SCHEDULES OF REINFORCEMENTContinuous Reinforcement every correct response is reinforcedHowever - behavior is produced by continuous reinforcement - provides little resistance to a behavior produced by extinctionExamplePartial ReinforcementIntermittent schedule produces a response that takes longer to extinguish than continuous reinforcementThink of SCHEDULES OF REINFORCEMENT as a CONTINUUMCR PR No R

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Fixed Ratio (FR) Schedule - Certain number of responses must be made before reinforcement is given ex. Reinforcement might be given after every 3 responses.Variable Ratio (VR) Schedule - Number of responses required for reinforcement to occur variesex. Slot MachineMachine provides reinforcement but can NEVER tell when it occurs. Your response rate is STEADY and HIGH.Ex. Lottery Ticket - person buys ticket each week in hopes of hitting the winnings.19

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Fixed Interval (FI) Schedule - subject receives reinforcement for the first response shown after a given time interval ex. Subject reinforced ONCE every 2 minutes ex. Students study to receive a test grade at the end of the semester. ex. Children GOOD “ALL” week to receive their allowance.Subject tends to rest immediately after a reinforcement and then increases frequency of responding just before the next reinforcement occurs.Variable Interval (VI) Schedule - Subject is reinforced for the first response given after a particular time interval which is CHANGED for each trial ex. One trial may have 2 minute interval, next 4 minute

interval

, 3

rd

1 minute interval

ex

. Teacher gives unannounced Quiz.

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Primary ReinforcementEffective without having been associated with other reinforcers. Ex. Food, water - serve as reinforcers without being paired with other reinforcersSecondary Reinforcement

Effective

only after it has been associated with a primary

reinforcer

Ex

. Why is it reinforcing to find a $20.00. It is valuable

to

you because associated with other

reinforcers

–>food

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Positive Reinforcement -occurs when a pleasant stimulus such as FOOD is presented and strengthens the response it followsNegative Reinforcement - Occurs when an aversive stimulus is removed and the preceding behavior is strengthened ex. Remove a painful stone from shoe; felt relief and experienced negative reinforcement ex. Escaping from a hot crowded room

ex. Taking a Tylenol when you have headache

Positive - as Presenting

Negative - as Removing

PR -

PRESENTING

something pleasant

NR - something

unpleasant is REMOVED

; also increases response

BOTH TYPES INCREASE IN BEHAVIOR

REMEMBER: Reinforcement Always increases the likelihood that the behavior will occur again.

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Punishment - Decreases the likelihood that the behavior preceding it will be repeatedThink of Punishment in 2 distinct formsPresentation of something UNPLEASANT after a behavior will lead to a decrease in the behavior = POSITIVE PUNISHMENT ex. Scolding a child, assessing a fineRemoval of something PLEASANT after a behavior will usually also lead to a decrease in the behavior = NEGATIVE PUNISHMENT

ex. Taking your car keys, keeping child in school during

recess

EFFECTIVE PUNISHMENT

Varies widely but dependent on the following characteristics:

PROXIMITY, CONSISTENCY, INTENSITY

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Proximity – closeness of the aversive stimulus to the punished behavior; the closer the more effectiveConsistency – always follow behavior with punishmentIntensity – strength of punishment *usually more consistent and intense punishment results in a more EFFECTIVE reduction in the undesired behaviorReinforcement and Punishment defined by their consequencesINCREASE BEHAVIOR = ReinforcementDECREASE BEHAVIOR = Punishment24

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Cognitive Learning learn by thinking about it or watching others.Utilizing mental structures and memory to make decisions about behavior.2KINDS1. Latent - EC Tolman2. OBSERVATIONAL - Albert BanduraLatentIndividual acquires knowledge of something but doesn’t show it until motivated to do so.Observational = social learning theoryReinforcement is largely more in motivation rather than in the learning process itself Example - cheerleader

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For observational learning to be EFFECTIVE 4 processes must occur:1.Attention 3. Reproduction2. Retention 4. Motivation1. Attention - must pay attention to role model We do this most often when we are motivated and believe the behavior has some relevance to us2. Retention – must store our observations in our memory in symbolic form3. Reproduction - must be able to convert the symbolic representations that

we

have stored in our memory into appropriate behavior

4.

Motivation

- Behavior must be reinforced in order to motivate us to repeat it

with

any regularity

Observational Learning helps explain the

rich cultural diversity

shown by people all around the world.

Our customs and perhaps even our styles of thinking are dependent upon our observational experiences

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PQ4R1. Previewing2. Questioning3. Reading4. Reflecting5. Reciting6. Reviewing27