A team of US scientists has reportedly discovered that the site in the human brain that controls language in right-handed people shifts with ageing.
The researchers from the Department of Neurology at the University of Cincinnati (UC) Academic Health Center claim that the new findings could help in the treatment of speech problems resulting from traumatic brain injury or stroke.
The site of language activity in right-handed people starts on the left side of the brain, but as early as aged five it starts to shift and becomes a function shared by both sides of the brain. The research found that between the ages of about 25 to 67, "the site becomes more evenly distributed, until language activity can be measured in both hemispheres simultaneously".
The study, which will be published in detail in the February 2006 edition of the journal Human Brain Mapping, concludes that the shift in the site of language activity could explain why children that have had a large portion of one side of the brain surgically removed often recover completely.
The research team studied brain activity in 177 right-handed children and adults aged 5 to 67 at Cincinnati's University Hospital and Cincinnati Children's using functional magnetic resonance imaging (fMRI).
Dr Jerzy Szaflarski, assistant professor at the centre, who led the study, said: "This knowledge may give new hope for rehabilitation of brain function in adults after stroke or traumatic brain injuries. The fact that language adaptability is seen even in the older people supports the notion that these patients can be rehabilitated and returned to productive life, possibly even after a devastating stroke."