Ivan Petrovich Pavlov: Discoveries in Behavioral Psychology
... of Experimental Medicine in St. Petersburg. Between 1891 and 1900, Pavlov did most of his research on physiology of digestion at the Institute of Experimental Medicine. In 1897, he published his lectures entitled ‘Lectures on the functions of the principle digestive glands.’ In 1901, Pavlov was elected as a corresponding member of the Russian Academy of Sciences. Three years later in 1904, Pavlov received the Nobel Prize in Physiology and Medicine for work on the psychology and physiology of the digestive glands. In 1907, he was elected Academician of the Russian Academy of Sciences and five years later, in 1912, he was given an honorary doctorate at Cambridge University. Pavlov was then awarded the Order of the Legion of Honour in 1915. On January 24 1921, the government of Russia awarded him with a special government decree signed by Lenin. In 1924, Pavlov decided to resign from professorship at the Military-Medical Academy. Eleven years later in 1935, his son Vsevolod died from an unknown cause. That same year, the government built a laboratory for Pavlov with his chief work on conditional reflexes. On February 27, 1936, at the age of eighty-seven, Pavlov died in Leningrad, Russia. At first, “Pavlov became passionately absorbed with physiology” (Nobelprize.org lines 20-21). He worked to unveil the secrets of the digestive system through experimentation with dogs. Pavlov studied what signals triggered related phenomena, such as the secretion of saliva. When a dog encounters food, saliva starts to pour from the salivary glands located in the back of its oral cavity. This saliva is needed in order to make the food easier to swallow. Pavlov became interested in studying reflexes when he saw that the dogs drooled without the proper stimulus. 3 Although no food was in sight, their saliva still dribbled. It turned out that the dogs were reacting to lab coats. Every time the dogs were served food, the person who served the food was wearing a lab coat. Therefore, the dogs reacted as if food was on its way whenever they saw a lab coat. In a series of experiments, Pavlov then “tried to figure out how these phenomena were linked. For example, he struck a bell when the dogs were fed. If the bell was sounded in close association with their meal, the dogs learned to associate the sound of the bell with food. After a while, at the mere sound of the bell, they responded by drooling” (Explanation Guide lines 106-109). According to the Explanation Guide, the experiment, in detail, with Pavlov and his dogs was as follows: Pavlov exposed dogs to repeated pairings of a tone and food. Again and again, a tone was audible for several seconds and then the dog was given a small portion of food. Before these pairings, the dog had innate, unconditional, food-related responses (most famously, salivation) to the food, but no food-related reactions to the tone. The food, therefore, was called an unconditional stimulus (abbreviated US or UCS), and salivation was called an unconditional response (abbreviated UR or UCR). These terms were chosen to reflect that no experience or conditions were needed for this stimulus-response relationship to occur. The food and tone were part of an unconditional reflex. The tone, however, initially elicited no food-related responses, and was therefore termed a neutral stimulus (abbreviated NS). After the dog experienced the pairings of the tone and food, however, the effects of the tone were changed. The previously neutral tone began to elicit salivation. The newly conditioned tone, therefore, was called a conditional stimulus (abbreviated CS) because its effects on food-related responses were upon the 4 dog’s experiences. The salivation elicited by the tone, also conditional upon the dog’s experience, was called conditioned (or conditional) response (abbreviated CR). After conditioning, the tone and salivation were part of a conditional reflex (lines 35-60). Pavlov came to call this the conditioned response, better known as classical conditioning today. This accidental discovery of classical conditioning sparked Pavlov to experiment further with the dogs in order to try and fully understand these reflexes. According to the Explanation Guide, “classical training – also called ‘pavlovian conditioning’ or ‘respondent conditioning’ – involves learning about the association of two or more (usually external) stimuli” (lines 28-29) and that “when two things generally occur together, encountering one can bring the other to mind” (line 31). “This study [of the dogs] is one of the most used studies in classical conditioning. Basically, what this study proved was that the dogs became conditioned by Pavlov to have exp...