Language map of brain to restore language redrawn

A language map of brain that will help develop better therapies to restore language has been redrawn, says new research.

A team of scientists from Northwestern University have redrawn the map. They have updated the traditional brain map of language comprehension based on new research with individuals who have a rare form of dementia that affects language.

The new work shows that word comprehension is actually located in a different brain neighbourhood -- the left anterior temporal lobe.

"Also, sentence comprehension turns out to be distributed widely throughout the language network, not in a single area as previously thought," the team said.

"This provides an important change in our understanding of language comprehension in the brain," said lead study author Marek-Marsel Mesulam, director of Northwestern's cognitive neurology and Alzheimer's disease centre.

For 140 years, scientists' understanding of language comprehension in the brain came from individuals with stroke.

Based on language impairments caused by stroke, scientists believed a single area of the brain -- a hot dog shaped section in the temporal lobe of the left hemisphere called Wernicke's region -- was the centre of language comprehension.

Wernicke's was thought to be responsible for understanding the meaning of single words and sentences, two separate and critical functions.

Knowing where language comprehension is located offers a more precise target for future therapies that could potentially protect or restore language function.

The paper is forthcoming in the journal Brain.