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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