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Classical Conditioning Slide One: Why do we learn? We learn to adapt to our environment. Ivan Pavlov demonstrated how through classical conditionings we learn to anticipate events like being fed or experiencing pain. Learning is a relatively permanent change in an organism’s behavior due to experience. Nature provided us the most important gift of adaptability—our capacity to learn new behaviors that enable us to cope with ever-changing experiences. We learn by association. Our minds naturally connect events that occur in sequence. Slide Two: Stimulus-stimulus learning is learning to associate one stimulus with another. In stimulus-stimulus learning, the learner learns to associate one stimulus with another stimulus. See how the boy observes the lightening, hears the clap of thunder, and THEN winces. After the lightening and thunder have been repeated, the boy sees the lightening strike, winces, THEN hears the clap of thunder. This boy demonstrates stimulus-stimulus learning when he responds to a lightening strike by wincing. Slide Three: Ivan Pavlov’s name should ring a bell for you. Pavlov’s research on classical conditioning verified associative learning principles in which organisms associate stimuli and thus associate events. Pavlov’s research on the digestive system led to a Nobel prize in 1904 and spawned other learning theorists such as the behaviorist John B. Watson with his Little Albert study, B.F. Skinner’s “Skinner Box”, and taste aversion research by John Garcia in the 1960s. As you can see, an uncontrolled stimulus (US) - food - produces an unconditioned response (UCR) - salivation. A neutral stimulus (NS) in the form of a bell tone produces no salivation. After repeated presentations of a neutral stimulus in the form of a bell tone just prior to the showing the unconditioned stimuli - food, the neutral stimulus triggers the unconditioned response, salivation. After several repetitions, the neutral stimulus tone becomes the conditioned stimulus (CS) because the conditioned stimulus triggered a conditioned response (CR) - salivation. That is to say, the sound of the bell tone elicits the dog’s salivation. © 2012 Aventa Learning Responses are acquired—that is, initially learned—best when the conditioned stimulus (CS) is presented half a second before the unconditioned stimulus (US). This finding demonstrates how classical conditioning is biologically adaptive. Extinction happens when the Unconditioned Stimulus (food) does not follow the Conditioned Stimulus (tone) for a period of time. Conditioned Response (salivation) starts to decrease and at some point goes extinct. Spontaneous recovery occurs if after a rest period, an extinguished Conditioned Response (salivation) spontaneously recovers and if Conditioned Stimulus (tone) persists alone becomes extinct again. Generalization is the tendency to respond to stimuli similar to the Conditioned Stimuli. Pavlov conditioned the dog’s salivation (CR) by attaching miniature vibrators (CS) to the thigh. When he subsequently stimulated other parts of the dog’s body, salivation dropped. Generalization has survival value because it extends a learned response to other stimuli in a given category; for example, fleeing from all snakes, not just poisonous ones, since it’s difficult to distinguish poisonous from nonpoisonous ones from a safe distance. Discrimination is the learned ability to distinguish between a Conditioned Stimulus and other irrelevant stimuli. Discrimination has survival value because it limits our learned responses to appropriate stimuli; for example, fleeing from a rampaging lion but not from a playful kitten. Slide Four: Early behaviorists believed that learned behaviors of various animals could be reduced to mindless mechanisms. Research indicates that, for many animals, cognitive appraisals are important for learning. That is, thoughts and perceptions are important to the conditioning process. However, later behaviorists suggested that animals learn predictability of a stimulus, thus learning expectancy or awareness of a stimulus (Rescorla, 1988). For example, animals, including humans, appear capable of learning when to expect an unconditioned stimulus, and their awareness of the link between stimuli and responses can weaken associations. Pavlov and Watson believed that laws of learning were similar across all animals. Learning in a pigeon and a person was not different. The early behaviorists’ view that any natural response could be conditioned to any neutral stimulus has given way to the understanding that each species is biologically prepared to learned associations that enhance its’ survival. However, later behaviorists suggested that learning was © 2012 Aventa Learning constrained by an animal’s biology. Thus, humans more easily learn to fear bears and hornets than to fear eagles. Rats develop aversions to tastes but not to sights or sounds. Conditioning occurs best when the CS and the US have just the sort of relationship that would lead a scientist to conclude that the CS causes the US. Garcia showed that duration between CS and US can be long (hours) and yet result in conditioning. Biologically adaptive CS (taste) led to conditioning and not others (light or sound). Even humans develop classically conditioned nausea. Slide Five: Watson used classical conditioning procedures to develop advertising campaigns for a number of organizations including Maxwell House, making “coffee break” an American custom. Classical conditioning principles provide important insights into drug abuse and how it may be overcome. Classical conditioning works on the body’s disease-fighting immune system. For example, when a particular taste accompanies a drug that influences immune responses, the taste by itself may come to produce those immune responses. Watson’s “Little Albert” study demonstrated how classical conditioning may underlie specific fears. Today, psychologists use extinction procedures to control our less adaptive emotions and condition new responses to emotion-arousing stimuli. © 2012 Aventa Learning