VOA慢速英语2010年-Health Report - Study Adds to Understa(在线收听

This is the VOA Special English Health Report.
 
A new study suggests that the brain is even more complex than scientists have recognized

A new study of the brain is helping scientists better understand how humans process language. The study is being done in San Diego, Boston and New York.

One of the patients is a woman with epilepsy. Doctors are monitoring Denise Harris to see if she is a good candidate for an operation that could stop her seizures. They are monitoring her through wire electrodes implanted in her brain.

But while she is in the hospital, she is also helping scientists understand how the brain works with language. The study centers on a part of the frontal lobe called Broca's area. Pierre Paul Broca was a nineteenth century French doctor. He first recognized the big part that this small area plays in language.

The electrode implants have shown that the area very quickly processes three different language functions. Eric Halgren at the University of California, San Diego, School of Medicine is one of the main investigators. He says they found different regions doing, at different times, different processes all within a centimeter.

The first function deals with recognizing a word. The second deals with understanding the word's meaning within a sentence. And the third lets us speak the word.

Harvard University brain expert Steven Pinker is another author of the study. A report on the work appeared in the journal Science. Ned Sahin, a researcher at Harvard and the University of California, San Diego, School of Medicine, was the first author of the paper. He says scientists have known for some time that traditional explanations for how parts of the brain work need to be changed.

One such belief is that there is a separation of language tasks between two very different parts of the brain. One is Broca's area at the front. The other is Wernicke's area farther back in the brain. That area is named after the nineteenth century German neurologist Carl Wernicke.

The belief is that Broca's area is responsible for speaking and that Wernicke's area is responsible for comprehending. But the new study shows that Broca's area is involved in both speaking and comprehension. Neil Sahin says this shows how parts of the brain perform more than one task.

NEIL SAHIN: "Because here's an example of one relatively small part of the brain that's doing three very different things at three different times, but all within the space of a quarter of a second."

Yet, even with new findings like these, much about the brain still remains a mystery -- at least for now.

And that's the VOA Special English Health Report, with reporting by Mike O'Sullivan. I'm Jim Tedder.

  原文地址:http://www.tingroom.com/voa/2010/1/90360.html