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兩篇英文文章...

The two short articles are somewhat related to the areas of brain activated during  speech-language processing.

Men Do Hear -- But Differently Than Women, Brain Images Show
INDIANAPOLIS -- Research conducted at the Indiana University School of Medicine may help resolve an age-old dilemma between the sexes. Men listen with only one side of their brains, while women use both, according to information on brain imaging presented Tuesday, Nov. 28, at the 86th Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA).

The study may add fuel to the females' argument, but researchers say the findings don't address whether women are better listeners than men.

"Our research suggests language processing is different between men and women, but it doesn't necessarily mean performance is going to be different," said Joseph T. Lurito, M.D., Ph.D., assistant professor of radiology at IU School of Medicine. "We don't know if the difference is because of the way we're raised, or if it's hard-wired in the brain."

In the study, 20 men and 20 women underwent functional magnetic resonance imaging (fMRI) while listening to a passage from "The Partner," a John Grisham novel. A majority of the men showed exclusive activity on the left side of the brain, in the temporal lobe, which is classically associated with listening and speech. The majority of women showed activity in the temporal lobe on both sides of the brain, although predominantly on the left. The right temporal lobe traditionally is associated with non-language auditory functions. "As scientists, we're figuring out what normal is, and more and more often it seems we're finding that normal for men may be different than normal for women," said Micheal Phillips, M.D., assistant professor of radiology and co-author of the study. "That doesn't mean one is better or more capable than the other."

The finding may help with research regarding how men and women recover from stroke and brain tumors, said Dr. Lurito. It also may help guide brain surgeons in avoiding certain areas of the brain, depending on whether they're operating on men or women, he said. "Also, scientists working on improving imaging technologies, such as fMRI and PET (positron emission tomography), need to be aware of potential gender differences," said Dr. Phillips.

Source: URL: http://www.sciencedaily.com/releases/2000/11/001129075326.htm 

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Left Side Of Brain Activates Speech From Birth
For the first time, researchers have used functional magnectic resonance imaging (fMRI) to investigate infantbrain activity in response to speech. They found that, almost from birth, the brain's left hemisphere plays the leading role in processing most language functions. Presented Dec. 2 at the 89th Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA), these preliminary findings challenge the previously held belief that left-hemisphere dominance doesn't develop fully until puberty.

"Language lateralization seems to be established almost from birth," said Shantanu Sinha, associate professor of radiology at the David Geffen School of Medicine at UCLA, where the study is ongoing.

Lateralization is the activation of a function, such as speech, from the right or left side of the brain.

"To the best of our knowledge, this is the first time fMRI has been used to study infants," Sinha said. "Using fMRI, we can non-invasively study the neuronal response of newborns to stimulation of different kinds, without any ionizing radiation or pharmaceutical injenctions."

As part of a larger, longitudinal study monitoring the cognitive development of infants with brain injury from birth to age 2, the researchers performed fMRI exams on 42 infants with documented brain injury. The fMRI analysis included cases only where both sides of the brain were equally capable of developing, and excluded children with brain trauma evident on the MR images.

The infants were asleep but not sedated during the procedure. During fMRI, the infants listened through headphones to tapes consisting of scanner noise, nonsense speech and "motherese" speech. The experiments were not sensitive enough to establish whether the infant brains were able to distinguish between the two types of speech. However, definite left-hemisphere-dominant activation patterns appeared during the portions of the tapes containing speech, as opposed to during the portions containing scanner noise.

These early findings challenge the conventional theory that lateralization of language to the left hemisphere is progressive until puberty, starting from an initial state in which neither hemisphere dominates.

"Detailed knowledge about the neural mechanisms associated with increasing levels of speech should prove useful in the study of developmental language disorders, which are the single largest handicapping condition of childhood," Sinha said. "The mapping of specific brain-language relationships should foster understanding of the mental process underlying language itself."

Sinha's co-authors, all from UCLA, included Susan Bookheimer, Meena Garg, Lina Badr and John Grinstead. The National Institutes of Health funded the research.

Source: University Of California - Los Angeles 
URL: http://www.sciencedaily.com/releases/2003/12/031204075435.htm