Word: retina
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...standard device long used by eye doctors, is built around a six-volt bulb set in a revolving cylinder. In one side of the cylinder a window is cut to show a flashing light like a miniature lighthouse. The patient looks at the light through opalescent glass. If his retina and brain are getting a normal supply of blood and oxygen, the normal subject should see the flicker effect when the cylinder revolves as fast as 45 times a second. But if the eye's arteries are narrowed, the oxygen-starved retina loses sensitivity: the patient sees a steady...
...Bright light bleaches the visual purple, a pigment in the retina which is needed for vision in dim light. Overexposure slows the retina's power to restore the purple when needed...
...Lens & Retina. Their most notable conclusion in this period: the fibrous tissue was not a foreign growth between the lens and the retina (the sensitive screen upon which the lens focuses images), but a swollen, greyish transformation of the retina itself. It occurred when the babies were between two and four months...
...seven months old. Andrew Hoffmann and his pretty blonde wife thought both boys were blind, but at Presbyterian Hospital it was found that Dennis had some vision. On Kenneth, who had none, an ophthalmologist operated to remove part of the fibrous tissue. He believed that it was not the retina, but that the retina was shriveled and displaced. By last week, Dennis Hoffmann's vision was-improving slowly, but Kenneth was still sightless...
Giotto, says Ortega, was "a painter of solid and independent bodies." Three centuries later, Velasquez emphasized "hollow space"-the area between the eye and the thing seen. In recording only a dazzle of colored lights, the impressionists brought painting smack up to the retina. Picasso carried the same process a step further, painting what was back of the eyeball, inside his head. "[In the Picasso school] the eyes, instead of absorbing things, are converted into projectors of private flora and fauna. Before, the real world drained off into them; now, they are reservoirs of irreality...