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Hubel (Hubel), David H.

( The American neuroscientist Nobel Prize in Physiology or Medicine, 1981)

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Biography Hubel (Hubel), David H.
genus. February 27, 1926
American neuroscientist David Hunter Hubel was born in Windsor, Ontario. His parents, Elsa M. (Gunther) and Jess G. Hubel, a chemical engineer, were American-born. In 1929, Mr.. family moved to Montreal. David inherited his interest in science from his father in his youth fond of chemistry and electronics. He also discovered musical talent and subsequently, as he remarked, 'with five years gave the music a disproportionate amount of time'. From 1932 to 1944. He attended the Academy in Stretkona Autremonte.
In 1944, Mr.. H. was enrolled in McGill University, graduating with honors in mathematics and physics. After receiving a bachelor's degree in 1947. He went to medical school at the University, he considered, 'almost by lot, despite the lack of knowledge of biology'. Summer holidays he spent in the Neurological Institute in Montreal, studying the nervous system. In 1951, Mr.. after assignment to the medical degree X. began to study clinical neurology in the Neurological Institute, first in two years, and in 1954. - At Johns Hopkins University in Baltimore (Maryland).
The next year, X. was drafted into the U.S. Army and assigned to the Division of the Institute of neurophysiological studies of Walter Reed in Washington (DC). There, he developed a tungsten microelectrode - a device used to record the electrical impulses of the nerve cell. Suggest it in the brain of cats in certain periods of time, he could record the levels of spontaneous activity of nerve cells in the brain of sleeping and waking animals.
After his discharge from the army in 1958. H. continued his research in the laboratory Mauntkestla Vernon Johns Hopkins University. Mauntkestl was recognized center of Neurophysiology sensitive areas of the cerebral cortex. Since the laboratory equipment was flawed and needed to be updated, X, joined the research group of Stefan Kyufflera, who worked in Vilmerovskom Institute and Johns Hopkins University.
. Kyuffler, a leading specialist in the field of neurophysiology, studying nerve activity (or mikroelektricheskie potentials) of the nerve cells of the retina (the inner lining of the eyeball) cat
. He found that the retinal nerve or ganglion cells, responds to light contrasts and does not respond to uniform illumination. Kyuffler also described the receptive fields of the retina, which are characterized by a change in the stimulation of spontaneous neural activity of the cell. He found that the retinal ganglion cells are stimulated or inhibited when illuminated by the corresponding receptive fields round spot of light. If the light stimulates the cells of the retina, the light falling on the area surrounding this central point, inhibits cell, and vice versa.
X. and his colleague Torsten Wiesel had intended to study the receptive fields and other nerve cells in the visual analyzer, particularly those in the visual centers of the cerebral cortex. Vision centers are one of the many functional areas of the cerebral cortex, which carried him higher cognitive processes such as memory and perception. Visual Analyzer originates in the photoreceptor (light sensitive) cells of the retina, rods and cones. Nerve endings rods and cones are projected onto other cells in the retina, but their nerve impulses travel along the optic nerve in the lateral geniculate body, from which transferred to the visual centers of the cerebral cortex. Consisting of millions of nerve cells located in several layers, visual centers interpret the neural signals arising in the retina.
. One of the first observations made by Wiesel and H., has led to a significant expansion of the functioning of the nervous system
. Scientists placed a microelectrode in the visual centers in the cerebral cortex of cats and recorded spontaneous neural activity (or mikroelektricheskie potentials) of the nerve cell. Trying to cause nerve activity in the cells of the cortex, they tried a number of visual stimuli. Accidentally moving the microscope slide for the receptive field of a nerve cell, which was implanted microelectrode, X. noticed that the cell discharged early. First, the researchers came to the confusion concerning this phenomenon, but soon realized that the cell responds to a light strip of glass. While at Kyufflera retinal cells respond to the circular 'images', the nerve cells in the visual cortex respond to the linear light stimuli.
In 1959, Mr.. Kyuffler became a professor of pharmacology at Harvard Medical School in Boston (Massachusetts). Return passes and his research team, including X. and Vizela. In 1964, Mr.. Harvard created Department of Neurobiology, headed by Kyufflerom. In 1967. H. becomes head of the department, and the following year he was appointed professor of physiology. During my time at Harvard, X. Wiesel and held a series of experiments in which the microelectrode was placed in the visual centers in the cerebral cortex of live cats and monkeys, recording the spontaneous activity of nerve cells, which was implanted microelectrode. In this way they hoped to stimulate the retina of the field with a linear perception of light at different angles of orientation until until we find the most effective incentives for groups of cells along the path of the electrode. Sometimes they are injected perpendicular to the electrode surface of the brain, in other experiments carried out at an angle of electrode. After opening of the experimental animal data on the activity of neural tissue and its anatomical features were compared. Researchers have also developed a method of introduction of radioactive substances in the eyeball. Moving along the fibers of the optic nerve from the retina to the visual centers, these labeled substances help to get an idea of the anatomical features of the nervous tissue of the visual centers of the brain.
As a result of their experiments X. and Wiesel found that the visual centers of the cerebral cortex are organized in the form of periodic vertical systems, which they called the dominant visual columns and orientation columns. In these columns of nerve cells is necessary double refraction of the information transmitted from the retina to the visual centers. Dominant poles combine neuronal impulses from both eyes, while the orientation columns are transforming the circular receptive fields of retina and crank phone in the linear receptive. H. and Wiesel found that in the information processing involved a hierarchy of simple, complex and very complex nerve cells that function, according to scientists, according to the principle of increasing or progressive convergence. The principle of progressive convergence explains how in the visual cortex can create complete images of the many individual bits of information coming from the neurons of the retina. Similarly, can be organized in other functional centers of the cerebral cortex.
Research X. and Vizela of Neurophysiology view had a significant impact on clinical ophthalmology, especially in the treatment of congenital cataracts. For example, they found that such a cataract should be removed in early childhood, thus preserving sight.
Half of the Nobel Prize in Physiology or Medicine 1981. was divided between X. and Wiesel "for their discoveries concerning information processing in the visual analyzer '. The second half of the prize was awarded to Roger Y. Sperry. In a speech at the presentation of David Ottoson Karolinska Institute, reminded the audience that X. and Wiesel have shown, 'as the various components of the retinal image is read and interpreted by cells of the cerebral cortex ... The cells are shaped like columns, analysis occurs in strict sequence from one cell to another, and each nerve cell is responsible for a part in the whole picture '. Ottoson said that the researchers also found that the ability to decipher information from the retina, develops immediately after birth. This result is very important, because the inability to see at least one eye 'even a few days in this period ... can lead to permanent visual impairment '.
X. married in 1953. to Shirley R. Izard. They had three sons.
X. received an Honorary Doctorate from McGill University, . Lewis was awarded the Medal Rozenstila for basic medical research Brandeis University (1972), . aide John Friedenwald Award of the Association of Research and Ophthalmology (1975), . Karl Spencer Lashley Award of the American Philosophical Society (1977), . Prize Louise GrossHorvits Columbia University (1978), . Dickson Prize in Medicine University of Pittsburgh (1979) and George Ledley Prize at Harvard University (1980),
. He - a member of the National Academy of Sciences and the American Academy of Arts and Sciences.


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Hubel (Hubel), David H., photo, biography
Hubel (Hubel), David H., photo, biography Hubel (Hubel), David H.  The American neuroscientist Nobel Prize in Physiology or Medicine, 1981, photo, biography
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