Hockenbury Discovering Psychology 5th txtbk

186 CHAPTER 5 Learningclassical conditioningThe basic learning process that involvesrepeatedly pairing a neutral stimulus with aresponse-producing stimulus until the neutralstimulus elicits the same response.unconditioned stimulus (UCS)The natural stimulus that reflexively elicits aresponse without the need for prior learning.unconditioned response (UCR)The unlearned, reflexive response that iselicited by an unconditioned stimulus.conditioned stimulus (CS)A formerly neutral stimulus that acquiresthe capacity to elicit a reflexive response.conditioned response (CR)The learned, reflexive response to a conditionedstimulus.Pavlov’s extraordinary gifts as a researcher enabled him to recognize the importantimplications of what had at first seemed a problem—a reflex (salivation)that occurred before the appropriate stimulus (food) was presented. He also hadthe discipline to systematically study how such associations are formed. In fact,Pavlov abandoned his research on digestion and devoted the remaining 30 yearsof his life to investigating different aspects of this phenomenon. Let’s look at whathe discovered in more detail.Principles of Classical ConditioningThe process of conditioning that Pavlov discovered was the first to be extensivelystudied in psychology. Thus, it’s called classical conditioning (Hilgard & Marquis,1940). Classical conditioning deals with behaviors that are elicited automaticallyby some stimulus. Elicit means “draw out” or “bring forth.” That is, the stimulusdoesn’t produce a new behavior but rather causes an existing behavior to occur.Classical conditioning always involves some kind of reflexive behavior. Remember,a reflex is a relatively simple, unlearned behavior, governed by the nervous system, thatoccurs automatically when the appropriate stimulus is presented. In Pavlov’s (1904)original studies of digestion, the dogs salivated reflexively when food was placed ontheir tongues. But when the dogs began salivating in response to the sight of Pavlovor to the sound of his footsteps, a new, learned stimulus elicited the salivary response.Thus, in classical conditioning, a new stimulus–response sequence is learned.How does this kind of learning take place? Essentially, classical conditioning is aprocess of learning an association between two stimuli. Classical conditioning involvespairing a neutral stimulus (e.g., the sight of Pavlov) with an unlearned, naturalstimulus (food in the mouth) that automatically elicits a reflexive response (the dogsalivates). If the two stimuli (Pavlov food) are repeatedly paired, eventually theneutral stimulus (Pavlov) elicits the same basic reflexive response as the natural stimulus(food)—even in the absence of the natural stimulus. So, when the dog in thelaboratory started salivating at the sight of Pavlov before the food was placed on itstongue, it was because the dog had formed a new, learned association between thesight of Pavlov and the food.Pavlov used special terms to describe each element of the classical conditioningprocess. The natural stimulus that reflexively produces a response without priorlearning is called the unconditioned stimulus (abbreviated UCS). In this example,the unconditioned stimulus is the food in the dog’s mouth. The unlearned, reflexiveresponse is called the unconditioned response (or UCR). The unconditionedresponse is the dog’s salivation.To learn more about his discovery, Pavlov (1927) controlled the stimuli that precededthe presentation of food. For example, in one set of experiments, he used aLife in Pavlov’s Laboratories DuringPavlov’s four decades of research, morethan 140 scientists and students worked inthe two laboratories under his direction.Twenty of his co-researchers were women,including his daughter, V. I. Pavlova.Pavlov, who had an extraordinary memoryfor details, carefully supervised the proceduresof dozens of ongoing research projects.Nevertheless, he acknowledged thatthe scholarly achievements produced byhis laboratories represented the collectiveeffort of himself and his co-workers(Windholz, 1990).