大脑某些区域功能可相互转换

When your brain encounters sensory stimuli, such as the scent of your morning coffee or the sound of a honking car, that input gets shuttled to the appropriate brain region for analysis. The coffee aroma（芳香） goes to the olfactory（嗅觉的） cortex, while sounds are processed in the auditory cortex. That division of labor suggests that the brain's structure follows a predetermined, genetic blueprint. However, evidence is mounting that brain regions can take over functions they were not genetically destined to perform. In a landmark 1996 study of people blinded early in life, neuroscientists showed that the visual cortex could participate in a nonvisual function — reading Braille.

Now, a study from MIT neuroscientists shows that in individuals born blind, parts of the visual cortex are recruited for language processing. The finding suggests that the visual cortex can dramatically change its function — from visual processing to language — and it also appears to overturn the idea that language processing can only occur in highly specialized brain regions that are genetically programmed for language tasks.

"Your brain is not a prepackaged kind of thing. It doesn't develop along a fixed trajectory（轨道） , rather, it's a self-building toolkit（工具包） . The building process is profoundly influenced by the experiences you have during your development," says Marina Bedny, an MIT postdoctoral associate in the Department of Brain and Cognitive Sciences and lead author of the study, which appears in the Proceedings of the National Academy of Sciences the week of Feb. 28.