Flowingly

"A mind stretched to a new idea can never go back to its original dimension"

Neural plasticity

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Similarly, the cerebral regions of the blind people change when they compensate the lack of vision with the tactile sense.

Neural Plasticity

Mind’s Eye – A painting by Turkish artist Esref Armagan (left), blind since birth. Scientists at Beth Israel Deaconess have studied Armagan to see how his visual cortex functions when painting.” [find out more at NewScientist.com or at Boston.com]

“Kennedy put Armagan through a battery of tests. For instance, he presented him with solid objects that he could feel – a cube, a cone and a ball all in a row (dubbed the “three mountains task”) – and asked him to draw them. He then asked him to draw them as though he was perched elsewhere at the table, across from himself, then to his right and left and hovering overhead. Kennedy asked him to draw two rows of glasses, stretching off into the distance. Representing this kind of perspective is tough even for a sighted person. And when he asked him to draw a cube, and then to rotate it to the left, and then further to the left, Armagan drew a scene with all three cubes. Astonishingly, he drew it in three-point perspective – showing a perfect grasp of how horizontal and vertical lines converge at imaginary points in the distance. “My breath was taken away,” Kennedy says.” The art of seeing without sight – NewScientist.com

“For the past few years, they have been studying sighted subjects who volunteer to be blindfolded for five days and learn certain nonvisual tasks, including rudimentary Braille. In every case, before subjects donned the blindfold,functional MRI (fMRI) scans revealed little activity in their visual cortices during tactile tasks. After the subjects wore the blindfolds for two days, however, the scans showed bright patches of activity in the visual brain when the subjects used their fingers for tactile or Braille-reading tasks. By day five, the visual cortex glowed steadily during these same tasks. Yet two hours after the blindfolds were removed and the subjects’ eyes had readjusted, scans of the visual area of their brains were as dark as they’d been on day one. Once the blindfolds were removed, touching, handling objects, and Braille-reading no longer activated ”sight” in the seeing.The cortical adaptations that occur in the blindfold studies appear-and disappear-too quickly for any new nerve connections to grow, Pascual-Leone believes. He compares the adaptive pathways in the brain to detours after road blocks; building a new street takes a long time, he explains, but if there are other existing surrounding roads, they can be used right away.” Old brain, new tricks – Boston.com

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Written by flowingly

March 10, 2007 at 15:00

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