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Ragnar Arthur Granit

Picture of Ragnar Arthur Granit

Date of Birth: 10/30/1900

Age: 91

Birthplace: Riihimaki

Citizenship: Sweden

Background

Even as a schoolboy, he took part in the struggle for independence of Finland from Russia, for which he was awarded the Cross of Liberty IV degree "with the sword."

In 1919 he entered the University of Helsinki. During the summer training courses at the Academy of Abo he first decided to specialize in experimental physiology, but on the advice of his uncle, Dr. Lars Ringboma, passed a full medical course. His teacher in experimental physiology was Elna Kyle, later professor of philosophy.

In 1923 he received a master`s degree in philosophy. In 1926 adopted the proposal of Professor Karl Tigerstedt become an assistant at the Physiological Institute. In 1927 he received his doctorate, and in 1929 became an assistant professor.

In 1928, half a year spent in the laboratory of Sir Charles Sherrington at Oxford, and in 1932-1933 he returned, having received the scholarship of the Rockefeller Foundation. It belongs Sherrington discovery about the processes of stimulation and inhibition. He was able to establish that the nerves that control the two groups of the thigh and lower leg muscles, are linked in such a way that stimulation causes inhibition of one another.

In 1929-1931 he worked at the Foundation for Medical Physics Eldridge Reeves Johnson at the University of Pennsylvania at the invitation of Dr. D.V.Bronka. Back in Helsinki, he was appointed professor of physiology (1935). During the Winter War between Finland and Russia Granite she worked as a district physician in the three islands in the Baltic Sea, Corpo, Houtskar and Inyo, while performing the functions of a military doctor in the forts, raspolozhennyhv this region.

In 1940 he accepted the offer of the Royal Karolinska Institute in Stockholm. In 1945, his laboratory at the Karolinska Institute was transformed into the Department of the Medical Nobel Institute. The construction of new buildings, which ended in 1947.

While still a student, he was interested in the physiology of vision. In the mid 1920`s were first electrical impulses registered in certain nerve fibers, and then in the optic nerve eel.

The fact that the eye retina is the nerve center, wrote in 1894 Santiago Ramon y Cajal and. While at Oxford Granite carefully he studied the work of Sherrington and came to the conclusion that the braking processes play an important role in regulating the activity of nerve cells. He began to explore these protsessyov in visual function, particularly the retina.

While working at the institute, he met with Johnson H.Kefferom Hartline and George Wald, who worked on a similar theme.

First Granite used traditional methods of study, at the same time he managed to find out that the strong coverage of some areas of the retina inhibits the response in adjacent areas, and this, in turn, enhances the perception of the eye light contrasts. He was able to prove (by recording the activity of the retina as a whole), the details of the visual image developed as a result of excitation and inhibition of the nerve center of the retina itself.

Back at the University of Helsinki Granite became interested in the study of color vision.

Even in the 19th century. German physicist Ferdinand von Helmholtz suggested that the ability of the human eye to distinguish between colors due to the presence in the eye receptors (receptor - the end of the sensory nerve fibers or specialized cells that accept and convert the stimulus from the external or internal environment, convert the energy of the physical and chemical processes in the excitement that is transmitted through nerve fibers in the central nervous system), sensitive to different wavelengths of light. Helmholtz (and simultaneously with the English scientist Yang) suggested that in the retina there are only three types of receptors, which receive the red, green and purple colors, and the rest are the result of the combined stimulation of the three main receptors.

Granite has developed a method for detecting electric pulses using microscopic electrodes, and established the existence of three types of receptors that are sensitive to red, green and blue. In the 1950s, the theory of Granite has been experimentally confirmed George Wald, who managed to identify three of the receptors corresponding pigment.

In 1945 Granite began to study the muscle spindle (receptor species). By that time it was already known that these bodies control static postures and reflex movements. He approached the problem more widely, putting the task to establish the relationship between the muscles, motor neurons (nerve cells that control the contraction and relaxation of muscles) and spindle nerves in the spinal cord and brain.

In 1967 Granite (with Hartline and Wald) he won the Nobel Prize in Physiology or Medicine "for their discoveries concerning the primary physiological and chemical visual processes in the eye".

Granite - a member of the Medical Research Council (1949-1955), President of the Royal Swedish Academy of Sciences (1963-1965), Vice-President (1965-1969).

Honorary Doctor of Oslo University (1951), Oxford (1956), Hong Kong (1961), Loyola (Chicago) (1969), Pisa (1970), San Marco (Lima), Santiago de Chile and the National University in Bogota (all in 1958) . Foreign Member of the Royal Swedish Academy of Sciences (1944), the Academy of Paris Sciences (1947), the Academy of Bologna Sciences (1948), American philosopher of society (1954), the Royal Danish Academy of Sciences (1956), the Royal Society of London (1960), National Academy of Sciences in Washington DC (1968), honorary member of the Academy of Medicine of Turin (19612), the Indian Academy of Sciences (1964), the American Academy of Arts and Sciences (1971). Honorary member of many professional societies: the Swedish Society of Neurology, Ophthalmology and clinical neurophysiology, the International Society for electroretinography, biological communities Montevideo, Santiago de Chile and Argentina.

Works: On the Correlation of some Sensory and Physiological Phenomena of Vision