2007年4月5日 星期四

English Quiz 176

(English Quiz 176)

1. Neuroscientists have long been convinced that the first few years of life are a crucial period for brain development--a time when connections between neurons are being forged at a prodigious rate as a baby learns to make sense of the external world. Interfere with that process, and you can cause permanent, irrevocable damage. If a child is born blind, for example, it's pretty much over by age 6. You can fix the eyes, and they might be able to perceive light and dark. Without the right visual circuitry in place, though, there's no way to form images--the essence of true sight.
Q: 試翻 "You can fix the eyes, .. the essence of true sight."

2. But then there's the patient known as S.R.D. Discovered by researchers four years ago in Ahmedabad, India, she was a 32-year-old, dirt-poor maid who had been born with severe cataracts. They were removed surgically when she was 12--and within a year, despite what neuroscientific dogma would have predicted, S.R.D. learned to see. Her case, described in the December issue of Psychological Science, is forcing scientists to rethink their long-held beliefs about vision. "There is a critical period for perfect acuity," says Pawan Sinha, associate professor of neuroscience at M.I.T. and a co-author of the paper. "But there is not a critical period for learning to do complex visual tasks." This surprising insight had its genesis in 2002 when Sinha traveled to his native India --where nearly half a million children suffer from blindness. Many of these cases would have been preventable with the proper medical care, and, says Sinha, "I wanted to help the children get treatment." So with funding from the National Institutes of Health, he launched Project Prakash (it means "light" in Sanskrit), a humanitarian initiative to help expand eye care in India.
Q: 試翻 "This insight had its genesis ... with medical care."

3. Since hearing S.R.D.'s story, the researchers have analyzed a total of 14 children and one adult at the eye hospital. All of them have shown significant improvement in less than a year. While most were treated surgically, the adult--a 29-year-old man with congenital aphakia (an eye missing its lens)--just needed a pair of glasses. Eighteen months later, he was able to see. Although the results are undeniable, it's still unclear what's going on in the patients' brains. The researchers will start to explore this question next summer by taking pictures of the brain before and after surgery using functional magnetic resonance imaging (fMRI) scanners. Since the brain devotes roughly 35% of its power to vision, they hypothesize that when this sense is compromised, others, like smell and touch, take over the visual-processing circuits. After surgery, they suspect, the sense of sight reclaims its territory inside the brain.
Q: 試翻 "Since the brain devotes roughly ... inside the brain."

沒有留言: