Learning. Learning. Learning via Association 1/8/2012. Chapter Eight. Change in an organism s behavior or thought as a result of experience

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1 Chapter Eight Learning Learning Change in an organism s behavior or thought as a result of experience Many different kinds, most basic are habituation and sensitization Responding to stimuli less or moreover time Learning via Association Large amounts of learning occur though association The British Associationists believed we acquired most knowledge via conditioning Simple associations provided the mental building blocks for more complex ideas 1

2 Ivan Pavlov Russian physiologist and 1904 Nobel Prize winner Most famous for work on digestion of the dog This included the first work on classical conditioning Classical Conditioning Involves five primary components Neutral stimulus (NS) Unconditioned stimulus (UCS) Unconditioned response (UCR) Conditioned stimulus (CS) Conditioned response (CR) 2

3 Classical Conditioning Steps 1. Start with a neutral stimulus, which does not elicit a particular response Metronome 2. Pair the NS again and again with the unconditioned stimulus, which elicits an unconditioned response Meat powder and salivation Classical Conditioning Steps 3. Eventually, the NS becomes a conditioned stimulus, eliciting a conditioned response Metronome and salivation The organism reacts the same wayto the previously NS as it did to the UCS 3

4 CC Principles Acquisition is the phase during which a CR is established Extinctionis the reduction and elimination of the CR after the CS is presented repeatedly without the UCS 4

5 CC Principles Stimulus generalization is when similar CSs elicit a CR Driving a new car Stimulus discriminationis when we exhibit a CR only to certain stimuli, not similar others Movie about tornado vs. tornado in real life Concept Check: A puff of air is blown into a rabbit s eye just after a musical tone is played. After several repetitions of this procedure, the rabbit closes its eye when the musical tone is played. What are the: US UR Neutral Stimulus/CS CR UCS Air puff UCR Closing eye Neutral stimulus/cs Musical tone CR Closing eye 5

6 Higher Order Conditioning Process where organisms develop classically conditioned responses to CSs associated with the original CS Becomes weaker the farther from the original CS Want a Coke? Applications of CC Advertisers repeatedly pair their products with stimuli that elicit positive emotions Can show latent inhibition Applications of CC Helps to explain how and why we acquire some fears and phobias Little Albert Can also help to treat phobias Little Peter 6

7 Applications of CC Fetishism seems to be partly due to classical conditioning Japanese quails and terrycloth cylinders Disgust reactions to safe food and drink Operant Conditioning Learning controlled by the consequences of the organism s behavior The organism gets something because of its response Also known as instrumental conditioning CLASSICAL CONDITIONING Target behavior is Elicited automatically OPERANT CONDITIONING Emitted voluntarily Reward is Provided unconditionally Contingent on behavior Behavior depends primarily on Autonomic nervous system Skeletal muscles 7

8 The Law of Effect If we re rewarded for a response to a stimulus, we re more like to repeat that response to the stimulus in the future Learning involves an association between a stimulus and response (S-R), with the reward stamping in this connection E.L. Thorndike Discovered principles of the law of effect after experimenting with cats in puzzle boxes Found no insightin cats 8

9 B.F. Skinner Followed up on Watson and Thorndike s work on behavior Designed the Skinner boxto more effectively record activity Operant Conditioning Terminology Reinforcementsare outcomes that strengthen the probability of a response Positive reinforcement involves giving a stimulus Negative reinforcementinvolves taking away a stimulus 9

10 Operant Conditioning Terminology Punishmentis any outcome that weakens the probability of a response Like reinforcement, can be positive or negative Disciplinary actions are punishments onlyif they decrease the chance of the behavior happening again Positive Reinforcement Negative Reinforcement Positive Punishment Negative Punishment PROCEDURE EFFECT EXAMPLE Presentinga stimulus Increases target behavior Gold star on homework makes student feel special Removing a stimulus Increases target behavior Static on phone that subsides when you move to a different spot Presentinga stimulus Decreases target behavior Scolding a dog to stop chewing on shoes Removing a stimulus Decreases target behavior Taking away a toy to stop a child from throwing a tantrum 10

11 Does Punishment Work? Not as well as reinforcement, say many Has several disadvantages Tells what notto do Creates anxiety Encourages subversive behavior May provide model for aggressive behavior Operant Conditioning Terminology A discriminative stimulus signals the presence of reinforcement Acquisition, extinction, spontaneous recovery, stimulus generalization, and stimulus discrimination all apply in OC Schedules of Reinforcement Refers to the pattern of delivering reinforcers Simplest is continuous reinforcement Partial reinforcementoccurs when we reinforce responses only some of the time More resistant to extinction 11

12 Schedules of Reinforcement Vary along two dimensions Consistency of administering reinforcement Fixed or variable The basis of administering reinforcement Ratio or interval Schedules of Reinforcement Fixed Ratio - after regular number of responses Variable Ratio-after specific number of responses, on average Fixed Interval-after specific amount of time Variable Interval- after an average time interval 12

13 Each schedule yields distinctive response patterns Applications of OC Animal training using shaping by successive approximations and chaining Overcoming procrastination via the Premack principle Development of superstitious behavior Applications of OC Using token economies in clinical settings to shape desired behaviors Primary and secondary reinforcers Applied behavior analysisfor language deficits in autism 13

14 Combining CC and OC Two-process theory of anxiety says it begins by classical conditioning, but is maintained by negative reinforcement 1. I am bitten (UCS) by a dog (CS), resulting in fear (CR) 2. I then avoid any dogs I see, which makes my anxiety decrease (negative reinforcement) Observational Learning Simply means learning by watching others Don t have to engage in trial and error to learn how to do something new Bandura s research on observing aggression Reel and Real World Violence Many types of research has examined the impact of violent media on behavior Results suggest that media violence impacts real-world aggression in some cases But, media violence is only one small contributor to real-world aggression 14

15 Biological Influences on Learning Conditioned taste aversions Develop after only one trial Can have very long delays (6-8 hours) Show little generalization Contradicts equipotentiality Biological Influences on Learning Preparednessfor certain phobias also contradicts equipotentiality We are evolutionarily predisposed to be more afraid of certain things Snakes and spiders vs. cars and guns May make us develop illusory correlations 15