Pavlov’s dogs would eventually stopped salivating to CS (tone) alone, but how about Carol is still fearing the cars even though she was not in additional car crashes?
Classical Conditioning Classical Conditioning Even when a CR extinguishes, not all traces are erased. Suppose we conditioned a dog to salivate to a tone. Then we presented the CS (tone) alone repeatedly and the dog stopped salivating. Later (for ex: 24 hours later) we presented the CS (tone) alone. The dog may salivate once again. This is called the Spontaneous Recovery.
Classical Conditioning Classical Conditioning Spontaneous recovery: the reappearance of a previously extinguished CR after a rest period and without new learning trials – The spontaneously recovered CR is usually weaker than the initial CR and extinguishes more rapidly in the absence of UCS.
Classical Conditioning Classical Conditioning Question? How would you explain why Carol fears all other cars, when it was her old car that was in the car accident?
Classical Conditioning Classical Conditioning • Stimulus generalization: stimuli similar to the initial CS elicit a CR – Example: Salivation may be elicited by a bell or a piano tone which are similar to the initial presented tone.
Classical Conditioning Classical Conditioning Assume that the stimulus generalization gone wild. For instance, Carol said that she’d turn off the TV if there are scenes involving car crashes. She generalized her fear of car crash to similar stimuli which becomes maladaptive. Organisms must be able to discriminate between irrelevant and relevant stimuli.
Classical Conditioning Classical Conditioning Discrimination: a CR occurs in the presence of one stimulus (tone) but not others (whistle) – Example: salivation may not be elicited by a whistle. – Carol’s fear response is not elicited by bikes or trains.
Generaliz -ation Discrimi- nation Extinction Spontaneous Recovery 1. Sinbad was frightened by a barking, lunging spaniel. Now he is afraid of all dogs. + 2. Sheila was frightened by a German shepherd when she was five, but now she is happy whenever she sees a dog. + 3. Makoto hates the sight of a bee, but loves to watch hummingbirds. + 4. When Kim was small, she got sick after eating a bad oyster. Now she refuses to eat anything that comes out of the sea. + 5. Romeo loves the smell of his girlfriend’s perfume, but thinks all other kinds of perfumes are unpleasant. + 6. Jamie had finally recovered from her fear of roller coasters, but one night when she was walking by the amusement park, the sudden screeching noise of the roller coaster made her heart jump in fear. + + 7. Leonardo used to love the scent of his girlfriend’s perfume, but now that they’ve broken up, it’s just another odor to him. +
Classical Conditioning Classical Conditioning Imagine we present a dog with many pairings of tone- food together, and the dog salivates intensely to the tone alone. Next, suppose that we present the dog with a neutral stimulus, say a black square which is followed by tone but no food.
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