Word: retina
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Dates: during 1990-1999
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RETIRING. KIRBY PUCKETT, 35, the Minnesota Twins' All-Star smiling outfielder and all-around class act; because of irreversible damage to the retina; in Minneapolis...
...theory is that the light that is transmitted back through the retina causes the production of melatonin," says Catlin. "There is some feeling, although it is not proven, that melatonin can sometimes counteract depression...
...second was the discovery of spatial organization in specific parts of the brain. At the surface of the brain, called the cortex, sheets of tissue preserve images from the retina of the eye in patterns of activity in neural cells...
...says the current theory, as a pattern of connections among neurons, the nerve cells that serve as the brain's basic building blocks. When information-the image of a new acquaintance's face, for example-enters the brain, it arrives in the form of electric impulses streaming from the retina, up the optic nerve and into the cerebral cortex, the so-called gray matter that houses the brain's higher functions...
Until recently, Zeki believed that without the area known as V1, the part of the brain that first receives input from the retina, conscious visual perception would be impossible. V1 is a sort of clearinghouse, a place where incoming signals are split up and sent to the sites where they can be processed. But one patient, a 38-year-old man whose V1 for one eye was wiped out in an automobile accident, is also quite clearly aware of motion seen by the "blind" eye even when the good eye is covered. "We find," says Zeki, "that he is consciously...