Brief Note about Ivan Pavlov - Science Odyssey


                         Ivan Pavlov
                         1849 - 1936

                         Ivan Pavlov was born in a small village in
                         central Russia. His family hoped that he would
                         become a priest, and he went to a theological
                         seminary. After reading Charles Darwin, he
                         found that he cared more for scientific
                         pursuits and left the seminary for the
                         University of St. Petersburg. There he studied
                         chemistry and physiology, and he received his
                         doctorate in 1879. He continued his studies
                         and began doing his own research in topics
                         that interested him most: digestion and blood
                         circulation. His work became well known, and
                         he was appointed professor of physiology at
                         the Imperial Medical Academy.

                         The work that made Pavlov a household name in
                         psychology actually began as a study in
                         digestion. He was looking at the digestive
                         process in dogs, especially the interaction
                         between salivation and the action of the
                         stomach. He realized they were closely linked
                         by reflexes in the autonomic nervous system.
                         Without salivation, the stomach didn't get the
                         message to start digesting. Pavlov wanted to
                         see if external stimuli could affect this
                         process, so he rang a bell at the same time he
                         gave the experimental dogs food. After a
                         while, the dogs -- which before only salivated
                         when they saw and ate their food -- would
                         begin to salivate when the bell rang, even if
                         no food were present. In 1903 Pavlov published
                         his results calling this a "conditioned
                         reflex," different from an innate reflex, such
                         as yanking a hand back from a flame, in that
                         it had to be learned. Pavlov called this
                         learning process (in which the dog's nervous
                         system comes to associate the bell with the
                         food, for example) "conditioning." He also
                         found that the conditioned reflex will be
                         repressed if the stimulus proves "wrong" too
                         often. If the bell rings repeatedly and no
                         food appears, eventually the dog stops
                         salivating at the bell.

                         Pavlov was much more interested in physiology
                         than psychology. He looked upon the young
                         science of psychiatry a little dubiously. But
                         he did think that conditioned reflexes could
                         explain the behavior of psychotic people. For
                         example, he suggested, those who withdrew from
                         the world may associate all stimulus with
                         possible injury or threat. His ideas played a
                         large role in the behaviorist theory of
                         psychology, introduced by John Watson around
                         1913.

                         Pavlov was held in extremely high regard in
                         his country -- both as Russia and the Soviet
                         Union -- and around the world. In 1904, he won
                         the Nobel Prize in physiology/medicine for his
                         research on digestion. He was outspoken and
                         often at odds with the Soviet government later
                         in his life, but his world renown, and work
                         that his nation was proud of, kept him free
                         from persectuion. He worked actively in the
                         lab until his death at age 87.

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