Word: braining
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Dates: during 1940-1949
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...prone position bed will also reduce blackouts. When an airplane pulls out of a dive or makes a sharp turn, the pilot's weight increases because of centrifugal force: if he is sitting the blood pulls into the lower part of his body, leaving his brain without proper blood supply...
...more neurologists learn about the human brain, the more it looks like an electrical calculating machine. And the more engineers learn about an artificial calculating device, the more it resembles the human brain. Last week, Neurophysiologist Warren McCulloch of the University of Illinois tried to describe the brain in purely electrical terms to a New York meeting of the American Institute of Electrical Engineers...
...brain, said Professor McCulloch, is made up of neurons (nerve cells) which are nothing more nor less than small electrical relays, each containing its own built-in power supply. The cells burn sugar to carbon dioxide and water, and use the energy produced to keep their outer surfaces electrically charged in relation to their interiors. The electrical tension (voltage) between the two parts is about seven-hundredths of a volt...
...cell "fires." An electrical disturbance starts at its center and travels outward along all its fibers. When the pulse reaches the end of a fiber and touches a fiber of another cell, it may or may not "fire" that cell, too. This selective action is the basis of the brain's operation...
Measured in electrical engineering terms, the neurons are only one-thousandth as fast as vacuum tube relays, but they require much less space and much less power. Professor McCulloch estimated that if a calculating machine had only 10 million vacuum tubes (the brain has about 10 billion neurons), it would take the power of Niagara Falls to operate it and the Niagara River to keep it from overheating. The brain is cooled by a comparatively small river of blood. When awake and in full operation, it raises the temperature of a pint of circulating blood one-half degree a minute...