Читать книгу The Form Within - Karl H Pribram - Страница 44

But meanwhile, to return for a moment to the notion of line detectors: the visual cortex cannot be processing straight lines or edges per se because the input from the retina is not received in the form of a straight line. As Leonardo da Vinci showed in the 15th century, the retina is a hemisphere. A perceived line must therefore be abstracted from a curve. When you fly from New York to London you travel via Newfoundland, Iceland and Greenland in an arc that describes the shortest distance between two points on the globe. On a sphere, the shortest distance on a globe is not a straight line. Riemann developed a geometry that applies to curved surfaces. The brain’s visual processing, therefore, must operate according to Riemannian principle and must be based on Pythagorean arcs, angles and cones, not on the points and lines of Euclidian geometry. Experimental psychologist James Gibson and his students at Cornell University have taken this aspect of vision seriously, but their work needs to be incorporated by brain scientists in their account of visual sensory processing.