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OLD BRAIN, NEW TRICKS NEW RESEARCH ON THE BLIND IS REVEALING THE BRAIN'S ; ABILITY TO ADAPT - AND MAY LEAD TO NEW THERAPIES FOR EVERYTHING FROM STROKES TO CHRONIC PAIN
[THIRD Edition]
Boston Globe - Boston, Mass.
Subjects: Medical research; Blindness; Brain
Author: Feinberg, Cara
Date: Jan 15, 2006
Start Page: K.1
Section: Ideas
Abstract (Document Summary)

ESREF ARMAGAN is a 52-year-old Turkish painter who has been blind in both eyes since the day he was born. He has never seen a coffee cup, a toothbrush, an elephant, or a tree-lined street, but he can draw them each, from any perspective, with or without shadows depending on the time of day. His portrait of President Clinton, which he painted from an embossed photograph, looks, well, like Clinton-complete with grey hair and bulbous nose-and though Armagan has never had an art lesson, the streets he paints stretch into the distance as converging parallel lines. For years, Armagan has been a phenomenon in the art world, displaying his work in museums around the globe. But it was not until two summers ago, when he traveled to Boston, that scientists were able to study precisely how he generates such images. Their hope was that he might teach them something about neural "plasticity"-the brain's ability to reorganize its functions based on new information and experiences. If Armagan had never seen with his eyes, how had his brain adapted to give him visual representations of the world, and more importantly, what could it reveal about brain adaptation in general? In July of 2004, at the Center for Noninvasive Brain Stimulation at Beth Israel Deaconess Hospital in Boston, Armagan agreed to have his brain imaged in a magnetic resonance imaging (MRI) machine while he drew with a pencil on a sheet of paper. He explored a set of objects by touch-a coffee cup, a toy elephant, a toothbrush-and then was told to imagine them and draw them all from memory. Each time, his drawings hit the mark. "What we saw in the scan was quite amazing," says Dr. Alvaro Pascual-Leone, an associate professor of neurology at Harvard Medical School and director of the center. He and two colleagues in Beth Israel Deaconess's neurology department, Amir Amedi, PhD, and Dr. Lotfi Merabet, conducted a series of scans, each time challenging Armagan with more complex tasks. "Esref's visual cortex lit up during the drawing tasks as if he were actually seeing," says Pascual-Leone. "His scan, to the untrained eye, might look like the brain of a sighted person." Armagan presented a unique learning opportunity for the scientists at Beth Israel Deaconess. Pascual-Leone and his colleagues had access to a blind person able to render-pictorially- what his mind's eye had captured. But more importantly, they now had the technology to look at his brain while he rendered it, and to glimpse how his visual cortex functioned after 52 years without vision. For centuries, scientists held that the brain was a fixed entity, that it was hard-wired for each individual function, and incapable of reorganizing after injury. In the late 1850s, the French neurosurgeon Paul Broca was the first to argue that language was associated with a specific part of the brain, and other investigators soon followed suit: The visual cortex at the back of the brain, they hypothesized, processed only vision, the somatosensory cortex in the mid-brain processed only pain, vibration, and touch, the auditory cortex on the sides of the brain existed solely to process sound. In the last half-century, however, new technology and cutting-edge experiments like those of Pascual-Leone and his colleagues, have exploded that dogma, revealing not only that the brain does in fact reorganize and adapt, it does so all the time. "What we saw in Esref," Pascual-Leone explains, "was that he was using his visual cortex. It wasn't lying dormant. It hadn't shrunk or disappeared. Instead, it was recruited by other senses."

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