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REFLEX PHYSIOLOGY – PRECURSOR TO BEHAVIORISM
Archimedes,
Palimpsest
(287-212 bc),
preeminent Greek mathematician and inventor, who wrote important
works on plane and solid geometry, arithmetic, and mechanics.
In mechanics, Archimedes defined the principle of the
lever and is credited with inventing the compound pulley. During his
stay in
Egypt he invented the hydraulic screw for raising water from a lower
to a higher level. He is best known for discovering the law of
hydrostatics, often called Archimedes' principle, which states that
a body immersed in fluid loses weight equal to the weight of the
amount of fluid it displaces. This discovery is said to have been
made as Archimedes stepped into his bath and perceived the displaced
water overflowing.
Archimedes helped the king to determine how much gold
was in the crown and used his volume displacement method like in his
bathtub experiments. He uses this principle to apply to Descartes
idea.
He had a person place their arm in a tube of water and
then contract and extend. If there were animal spirits that moved
from the brain into the arm for movement, then the arm should
increase in size and displace more water; however, the water did not
go up. This disproved Descartes theory.
Swammerdam, Jan
(1637 – 1680)
a 17th century Dutch microscopist, made major discoveries in
medicine and anatomy. Above all, he made a decisive contribution to
the development of biology and a materialist understanding of
nature.
Swammerdam surgically isolated a muscle and
disconnected the nerve from the brain and showed that stimulation of
nerve equaled movement.
DR. FRANCOIS MAGENDIE
(1783-1855)
Magendie,
who was born in France, obtained all of his education including his
medical training in his native country. Hs is identified as a
physician and a physiologist. Early, he was interested in the
physiology of digestion, later his areas of study included the
heart, the blood- Magendie repeat Charles Bell’s work on the
division of anterior and posterior spinal roots and demonstrated
that the posterior spinal roots and demonstrated that the posterior
root stimulation elicited pain while this stimulation of the
anterior root produced motor effects. He described the apertura
medialis ventriculi quarte- the foramen of Magendie. He showed that
by cutting the posterior spinal nerve lead to loss of feeling, but
kept motor activity. Cutting the anterior branch did the opposite –
still feeling, loss of motor.
Reflex
Arch:

A reflex is an unlearned correlation between a class of
stimuli and a class of responses. A reflex is not a stimulus or a
response. It’s the relationship between the two. A lot of behavior
is controlled reflexively.
DR. IVAN SECHENOV
(1829-1905)
Sechenov, born in Russia, was
known as the Father of Russian physiology. He introduced
electrophysiology into laboratories and also into teaching. His life
work was always concentrated on neurophysiology. He wrote a major
classic "The Reflexes of the Brain." He also maintained that
physiochemical factors in the environment of the cell are of equal
if not greater importance. He was in conflict constantly with the
government and his colleagues. He will also be remembered for his
intellect and his knowledge, as well as for his scientific
achievements.
Sechenov said that all behavior
can be accounted for by reflexes (unconditioned responding). He
proposed a reflexology. It is a replacement for psychology. He said
some stimuli are subtle and make some behaviors hard to predict. The
only problem with this was that there was no learning involved.
Pavlov, Ivan
Petrovich
(1849-1936)
Russian physiologist Ivan Pavlov won the
1904 Nobel Prize in physiology or medicine. Although best known for
his work on reflex behavior, Palov made major scientific
contributions to understanding the physiology of the digestive
stystem.
Russian psychologist Ivan Petrovich
Pavlov’s name has become synonymous with the research he conducted
on reflex behavior in animals. Pavlov demonstrated in experiments
that dogs that heard a bell ring at feedings became conditioned to
salivate at the sound of the bell. Pavlov, who also studied the
nervous system, heart, and digestive system, is shown here, third
from left, at work in his lab.
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