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Unit III: Learning Chapters 4 & 5 Unit III Lesson 1: Definition of Learning What is Learning? • Learning – Relatively permanent change in behavior • Brain physically changes in response to learning – Brought about by experience or practice – Any kind of change in the way an organism behaves is learning Pavlov and Classical Conditioning • Ivan Pavlov – Russian physiologist – Studied digestion in dogs • Dogs naturally salivate in response to food (reflex) • Pavlov’s dogs salivated in response to other stimuli as well – Labeled classical conditioning • Learning response to a stimulus other than the original • New response does not naturally occur in response to the stimulus, is learned Classical Conditioning Concepts • Unconditioned stimulus (UCS) – Naturally occurring stimulus – Leads to an involuntary response – Unconditioned: • “Unlearned” or “naturally occurring” • Unconditioned response (UCR) – Involuntary response to naturally occurring stimulus Classical Conditioning Concepts (2) • Conditioned stimulus (CS) – Stimulus is able to produce learned reflex response – Paired with the original unconditioned stimulus – Conditioned = “learned” – Neutral stimulus • Becomes conditioned stimulus when paired with an unconditioned stimulus • Conditioned response (CR) – Learned reflex response to a conditioned stimulus. – Sometimes called conditioned reflex Classical Conditioning Principles • CS must come before UCS • CS and UCS must come very close together in time – Ideally, only several seconds apart • Neutral stimulus must be paired repeatedly with UCS before conditioning takes place • CS is usually a stimulus that is distinctive from other competing stimuli Classical Conditioning Concepts (3) • Stimulus generalization – Respond to a stimulus similar to original conditioned stimulus with conditioned response • Stimulus discrimination – Not making a generalized response to similar stimulus – Similar stimulus was never paired with the unconditioned stimulus • Extinction – Disappearance/weakening of learned response • Follows removal or absence of the unconditioned stimulus (classical conditioning) – Removal of reinforcer (operant conditioning) Classical Conditioning Concepts (4) • Spontaneous recovery – Reappearance of learned response after extinction – Response usually weak and short-lived • Higher-order conditioning – Strong conditioned stimulus is paired with a neutral stimulus – Neutral stimulus to become a second conditioned stimulus Conditioned Emotional Response • Emotional response classically conditioned to occur to learned stimuli • Examples: – Fear of dogs – Emotional reaction to seeing an attractive person, baby animals, etc. – May lead to phobias – irrational fear responses • Vicarious conditioning – Classical conditioning acquired by watching the reaction of another person Taste Aversion • Conditioned taste aversion – Occurs after only one association • Biological preparedness – Animals learn associations with only one or few pairings – Survival value as animal could die with multiple tastings Why Classical Conditioning Works • Stimulus substitution – Pavlov’s explanation – Conditioned stimulus (CS) becomes substitute for unconditioned stimulus (UCS) due to close pairing of two • Cognitive perspective – Conditioning occurs because CS provides information or expectancy about UCS forthcoming