Half the brain can recognize words and faces, study finds

　　A study of brain plasticity and visual perception found that people who had half their brains removed as children could accurately identify the difference between two words or two faces more than 80 percent of the time. Given the volume of brain tissue removed, this accuracy highlights the limits of the brain’s ability to rewire itself and adapt to drastic surgery or trauma.
　　The findings, published today in the Proceedings of the National Academy of Sciences by researchers at the University of Pittsburgh, are the first-ever attempt to describe neuroplasticity in humans and understand whether a single brain hemisphere can perform tasks that are normally performed separately by the two sides of the brain. Features.
　　Neuroplasticity is the process that allows the brain to alter its activity and rewire itself structurally or functionally in response to environmental changes. Although brain plasticity peaks early in development, the brain continues to change into adulthood.
　　As we age, the two hemispheres of the brain become more specialized, with different responsibilities for each hemisphere. But there are limits to neuroplasticity, and this hemispheric preference can become more rigid over time.
　　What happens when the brain is forced to change and adapt under conditions of high plasticity? To answer this question, the researchers looked at a special group of patients who had surgery to remove one hemisphere of the brain as children to control seizures. The researchers separately tested the participants’ ability to recognize two words and two faces. It was found that the remaining brain hemisphere supports both functions. Word and face recognition differed between hemispherectomized and control subjects, but the difference was less than 10 percent, with an average accuracy of more than 80 percent. No matter which hemisphere was removed, the participants’ accuracy in face and word recognition was comparable.
　　”The reassuring thing is that losing half your brain doesn’t equate to losing half your function,” said study lead author Dr Michael Granovetter, adding to our understanding of neuroplasticity in the postoperative brain. “Studies of hemispherectomized patients provide insight into the upper functional capacity limits of individual cerebral hemispheres. With this finding, we can now tap into the door of human neuroplasticity and begin to examine the brain’s ability to reorganize,” the researchers said.