PAVLOV’S DOGS IN CLASSICAL EXPERIMENT
Pavlov spent the first half of his long scientific career working on the physiology of digestion, turning to the study of learning in about 1900. He had noticed that dogs which salivate copiously when given food also do so in response to other events – for example, at the approach of the laboratory attendant who supplied the food. This response was clearly acquired through experience. Pavlov (1927) took a version of this procedure into the laboratory, making it a model system that could be used to reveal basic principles of learning. Pavlov’s standard procedure involved a quiet, distraction-free laboratory, which gave the experimenter full control over events experienced by a lightly restrained dog. From time to time the dog was given access to food, and each presentation was accompanied (usually slightly preceded) by the occurrence of a neutral event, such as a flashing light. After several training trials (pairings of light and food), the dog would salivate at the flash of light, before any food had appeare.
Salivation at the presentation of food is called an unconditioned response (UR) [unconditioned response (UR) evoked by a stimulus before an animal has received any explicit training with that stimulus], since it occurs automatically (unconditionally). The food is an unconditioned stimulus (US)[unconditioned stimulus (US) evokes an unconditioned response]. The animal’s tendency to salivate when the light flashes is conditional on the light having been paired with food, so this is referred to as a conditioned response (CR)[conditioned response (CR) evoked by a conditioned stimulus as a result of classical conditioning] and the event that evokes it as a conditioned stimulus (CS)[conditioned stimulus (CS) evokes a conditioned response as a result of classical conditioning]. The whole training procedure was labelled conditioning. As other forms of training, introduced later, have also been described as conditioning, Pavlov’s version became known as classical conditioning.
[I.P. Pavlov (1849–1936), born the son of a priest in Ryazan (250 miles south-east of Moscow), moved in 1870 to study natural science and medicine in St Petersburg. He spent the rest of his life there conducting scientific research, first on the physiology of the digestive system (for which he was awarded a Nobel prize in 1904) and later on conditioned reflexes. Although the study of conditioned reflexes was taken up mostly by psychologists, Pavlov insisted that his approach as a physiologist was far superior to that adopted by the comparative psychologists of his day. His demonstration of the salivary conditioned reflex in dogs, for which he is widely known, was just the start of an extensive body of work, in which he analysed the conditioning process in detail, revealing phenomena and suggesting learning mechanisms that are still being actively investigated today.]
Pavlov spent the first half of his long scientific career working on the physiology of digestion, turning to the study of learning in about 1900. He had noticed that dogs which salivate copiously when given food also do so in response to other events – for example, at the approach of the laboratory attendant who supplied the food. This response was clearly acquired through experience. Pavlov (1927) took a version of this procedure into the laboratory, making it a model system that could be used to reveal basic principles of learning. Pavlov’s standard procedure involved a quiet, distraction-free laboratory, which gave the experimenter full control over events experienced by a lightly restrained dog. From time to time the dog was given access to food, and each presentation was accompanied (usually slightly preceded) by the occurrence of a neutral event, such as a flashing light. After several training trials (pairings of light and food), the dog would salivate at the flash of light, before any food had appeare.
Salivation at the presentation of food is called an unconditioned response (UR) [unconditioned response (UR) evoked by a stimulus before an animal has received any explicit training with that stimulus], since it occurs automatically (unconditionally). The food is an unconditioned stimulus (US)[unconditioned stimulus (US) evokes an unconditioned response]. The animal’s tendency to salivate when the light flashes is conditional on the light having been paired with food, so this is referred to as a conditioned response (CR)[conditioned response (CR) evoked by a conditioned stimulus as a result of classical conditioning] and the event that evokes it as a conditioned stimulus (CS)[conditioned stimulus (CS) evokes a conditioned response as a result of classical conditioning]. The whole training procedure was labelled conditioning. As other forms of training, introduced later, have also been described as conditioning, Pavlov’s version became known as classical conditioning.
[I.P. Pavlov (1849–1936), born the son of a priest in Ryazan (250 miles south-east of Moscow), moved in 1870 to study natural science and medicine in St Petersburg. He spent the rest of his life there conducting scientific research, first on the physiology of the digestive system (for which he was awarded a Nobel prize in 1904) and later on conditioned reflexes. Although the study of conditioned reflexes was taken up mostly by psychologists, Pavlov insisted that his approach as a physiologist was far superior to that adopted by the comparative psychologists of his day. His demonstration of the salivary conditioned reflex in dogs, for which he is widely known, was just the start of an extensive body of work, in which he analysed the conditioning process in detail, revealing phenomena and suggesting learning mechanisms that are still being actively investigated today.]
No comments:
Post a Comment