Potential therapies for individuals with traumatic brain injury were revealed in a study on human brain plasticity and visual perception. The brain’s capacity for structural and functional plasticity in response to experience change is known as neuroplasticity. The study was carried out by researchers at the University of Pittsburgh, and it was published in the Proceedings of the National Academy of Sciences. This research is the first of its kind to describe neuroplasticity in humans and determine whether or not each hemisphere of the brain is required for certain tasks.
There were 40 people total, including grownups who had previously had brain surgery on a child. In extreme cases of infantile epilepsy, a hemispherectomy may be performed to remove one cerebral hemisphere surgically. Researchers sought to better grasp the capabilities of a single brain hemisphere by studying hemispherectomy patients. Participants were tested on their ability to distinguish between words that only differed in spelling by one letter, such as “soap” and “soup” or “back” and “buck.” Researchers quickly gave them matched sets of photographs of individuals in order to assess their ability to distinguish between similar looks. They were then asked to choose the option that best described the similarity (or dissimilarity) between the two sets of words or faces. More than 80% of the time, even after having half of their brain removed, the subjects were still able to correctly distinguish between pairings of words or faces.
Professor of ophthalmology and psychology and the study’s senior author, Marlene Behrmann, Ph.D., explains that their findings imply the brain may rewire itself. Much of the research in the fields of visual science and neurobiology is motivated by the issue of “whether the brain is prewired with its functional capabilities from birth or if it dynamically organizes function as it grows and encounters the world.” This study’s findings provide us a foundation on which to build our understanding of human neuroplasticity and the potential for brain remodelling. Age causes a greater differentiation between the hemispheres. In general, word recognition occurs mostly in the left hemisphere of the brain, whereas face recognition occurs primarily in the right. The results raise the possibility that severe functional impairment may not always follow once brain tissue is removed.
Sources:
PNAS: Breaking Science News (PNAS)
