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Nils Wiesel

Picture of Nils Wiesel

Date of Birth: 06/03/1924

Age: 92

Place of birth: Uppsala

Citizenship: Sweden

Background

In 1941 he enrolled in the VA health at the Karolinska Institute in Stockholm school. There, in the laboratory of Carl Gustaf Bernhard, he participated in studies of the nervous system function, as well as received clinical skills in psychiatry. In 1954, at the Karolinska Institute medical degree was awarded to him in the same year he was admitted to the Institute of Physiology and assistant professor in the department of child psychiatry at Karolinska Hospital.

The following year, B. accepted an invitation to do an internship in the Wilmer Institute, where he worked under the leadership of a major specialist in the field of neurophysiology of eye Kyufflera Stephen, who continued important research initiated H. Keffer Hartline and Ragnar Granit. Two years later, B. became an assistant professor in the physiology of organs in medical school at Johns Hopkins.

Kyuffler studied nerve activity (or mikroelektricheskie level) of nerve cells in the retina (inner membrane of the eyeball) cats. He found that the nerve or ganglion, retinal cells respond to light contrasts, and do not respond to uniform illumination. It is also described the receptive fields of cells (retina) that upon stimulation leads to a change of a nerve cell activity. Kyuffler found that the ganglion cell activity or increased or inhibited when light corresponding receptive field of retinal point source of light. If the central spot of light stimulates retinal cells activity, the light falling on the retina surrounding this spot, inhibits the activity of the cell, and vice versa.

When David H. Hubel in 1958 came to Kyufflera lab, he and B. decided to study the receptive field of nerve cells in the visual cortex. This area is one of the many functional areas of the cerebral cortex, in which the cognitive analysis. Visual Analyzer starts with a photoreceptor (light sensitive) cells of the retina, rods and cones. Nerve endings of rods and cones are projected to other retinal cells. From these cells nerve impulses travel through the optic nerve to the lateral geniculate body (subcortical structures), which are transmitted to the cortical center of vision. The visual cortex, consisting of many millions of nerve cells arranged in a plurality of layers, decrypts nerve signals, which came from the retina, and provides analysis of the visual information.

One of the first experiments of Hubel and clarified the function of the visual analyzer. Introducing a miniature electrode used to record the electrical activity of nerve cells in the visual cortex cats, they recorded the spontaneous neural activity, or mikroelektricheskie currents of the nerve cell. Researchers have experimented with various visual stimuli in an attempt to cause mikroelektricheskuyu activity in cells of the cerebral cortex. Once Hubel accidentally moved the microscope slide for the receptive field of a nerve cell containing a microelectrode. Suddenly the cell start to discharge. Initially, scientists were puzzled, but soon realized that the nerve cells of the cerebral cortex responds to the light strip of glass. While experiments in retinal cells respond to Kyufflera light spot, nerve cells in the visual cortex respond to linear light stimuli.

In 1959 Kyuffler became a professor of pharmacology at Harvard Medical School in Boston. B. was appointed assistant professor of physiology at Harvard, and in 1964 - professor of physiology. In the same year the department of neurobiology at Harvard led by Kyufflerom was created.

Continuing his studies in the new department, and V. Hubel microelectrode placed in the visual area of ??the cerebral cortex of cats and monkeys, recording the spontaneous activity of nerve cells with the microelectrode. Their task was to stimulate the field of linear poloskoysveta retina from different angles, yet not be able to find the most effective incentives for nerve cell rows along the path of the electrode. Sometimes they were administered an electrode in the vertical direction, while it turned out perpendicular to the surface of the brain; in other cases, the electrode was carried out at an angle to the surface of the brain. After opening the experimental animals the researchers compared the results of measurements of neural activity with histological data. They have also developed a method of introducing into the eyeball of radioactive substances, which are then moved along the optic nerve from the retina to the visual cortex, helping to more fully explore its neuroanatomy.

V. and Hubel found that the visual cortex is organized in the form of periodic vertical complexes, which they called the dominant visual columns and columns orientation. These columns of nerve cells produce the necessary processing of the information transmitted from the retina to the visual cortex. The dominant visual bars combined neuronal impulses from both eyes, whereas orientation - are transformed with circular receptive fields of the retina and the lateral geniculate body in line. V. and Hubel found that in the information processing involved a hierarchy of simple, complex and very complex nerve cells, which, according to these scientists, operate according to the principle of increasing or progressive convergence. This principle is explained in the visual cortex may be created from individual images finished multiple bits of information coming from the retinal neurons. Researchers have suggested that other functional areas of the cortex can be arranged in a similar manner.

B. Work and Hubel was of great importance for the treatment of ocular diseases, particularly congenital cataracts. They believed that such a cataract should be removed in early childhood, when the patient`s vision is preserved.

In 1968, V. became a professor of neurobiology at Harvard University, and in 1974 he was elected to the post of professor of neurobiology, established by Robert Winthrop. In 1973, V. Kyufflera replaced at the head of the department of neuroscience.

Half of the Nobel Prize in Physiology or Medicine 1981 was awarded to V. and Hubel "for their discoveries concerning the principles of information processing in neural structures of the brain"; the second half of the prize was awarded to Roger W. Sperry. Concluding Nobel lecture B. said that the "innate mechanisms provide visual analyzer highly specific connections, but to maintain and develop their needs visual experience early in life." B. Opening and Hubel explained one of the hidden mechanisms of brain activity - a way to decrypt the cells of the cerebral cortex of visual signals.

In 1983, B. was appointed professor of neuroscience at Rockefeller University, established Brooke Astor and Vincent.

In 1956 W. married Teri Stenhammer, and in 1970 they separated. He then married Anne Yee, with whom divorced in 1981

Among the prizes and awards B. - Lewis Rozenstila Prize for outstanding work in the field of basic medical research, awarded by the University Braydensa (1972), a commemorative medal of John C. Freed envalda Association for the Study of Vision and Ophthalmology (1975), Karl Spencer Lashley Award of the American Philosophical Society (1977), Prize Louisa Gross Horwitz Columbia University (1978), the Dickson Prize in medicine University of Pittsburgh (1979) and the award of George Ledley, Harvard University (1980). B. - Member of the American Physiological Society, the American Philosophical Society, the American Association for the Advancement of Science, the American Academy of Arts and Sciences, the US National Academy of Sciences. Society of Physiologists and the UK Royal Society of London.