Speakers and writers
There is something surprising about the way our brain organises the components of language. Kathleen Baynes, cognitive neurologist at the University of California, Davis, USA, and her colleagues studied an epileptic patient whose brain was surgically divided to control her seizures. They found that the centres for speech and writing, long thought to be in the same side of the brain, can reside in different hemispheres. Though it is hard to generalise from a single case, they suggest that spoken and written language can develop separately, and may lead to a new understanding of learning disorders. Neurones in the brain are constantly chattering like unruly children in a noisy classroom. But it is difficult to know which neurone does what. Neuro-scientists have failed to examine 'single' neurones in living people in the past. "The typical view is that all the components of language hang together on the same side of the brain. This shows that you can take them apart," says Alfonso Caramazza, cognitive neuropsychologist at Harvard University. The findings will help understand speech problems like dyslexia. Moreover, the fact that spoken and written language are not linked supports the idea that they evolved separately, says Baynes (Science, Vol 280, No 5365).