A new connection has been found between two of most important language areas in the brain. Broca’s area and Wernicke’s area have been linked to speech production and language comprehension respectively. They were some of the first discoveries that linked particular brain areas to specific mental abilities and are known to be joined by a bundle of neural fibres called the arcuate fasciculus.
Reseachers from London have now discovered that another parallel pathway connects the two areas, although it does not develop until about 5-7 years of age, suggesting that even quite major connections in the brain do not develop until well into childhood.
The pathway runs through an area they have named Geschwind’s territory after Norman Geshwind, the famous American neurologist who theorised that such a connection might exist.
Understanding the connectivity of the language areas is the brain is essential to the understanding and treatment of language problems after brain damage. These sorts of impairments are a common result of serious stroke or traumatic brain injury.
Link to story on newscientist.com.
Link to abstract from the Annals of Neurology.
3 thoughts on “Finding Geschwind’s territory”
Out of interest, do you know why Geschwind thought this connection might exist? I mean, kids can speak before the age of 5, so is there some kind of step-change in language ability that happens at that age that gave him a clue?
(I’d like to be able to talk to children and go “aaah you’ve not got your Geschwind’s territory yet.”)
It was almost certainly due to observing patients with language problems after brain injury. As one of the pioneers of cognitive neuropsychology he spent a lot of time studying the effects of brain injury to work out how the uninjured brain worked.
Hm, that New Scientist article (‘New language circuit discovered in humans’) points out that the age 5-7 is when people develop reading and writing skills.
Another question: Do you know of other, better understood, connections in the brain that develop after birth? I’d be interested to know of developments that correspond to visible skills. As a parallel, I’m thinking of muscle development. I’ve heard that boys and girls develop muscles in their hands at different rates, and this rate difference exhibits as boys, in general, not having the control necessary for writing until a few months after girls.