This is inevitable: connection congestion in the brain slows down our physical response time as we get older, according to new research.
This slower reaction is connected with age-related disorders of the corpus callosum which is part of the brain that functions as a dam during one-sided motor movements to prevent unwanted connections or cross communication between the two hemispheres of the brain, said Rachael Seidler, a professor at the University The Michigan School of Kinesiology and the Department of Psychology, and who is the chair of the study, as reported on August 19, 2010 by ScienceDaily.
At other times, the function of the corpus callosum as a bridge and cross communication, is useful as in certain cognitive functions or two-sided motor skills.
The University of Michigan study is the first to show that cross communication occurs even when older adults are at rest, said Seidler, who also took part in the Gerontology and Neurology Institute Advanced Study Program. This non-working cross communication shows that it is not beneficial for the two hemispheres to communicate during one-sided motor movements because the other side of the brain controls moving parts of the body. So, when both sides of the brain communicate simultaneously while one side of the body tries to move, there will be confusion and a slower response, said Seidler.
Previous studies have shown that cross communication in the brain during motor activity increases with age but it is not clear if cross communication helps or hinders brain function, Seidler said. Human Anatomy and Physiology 11th edition
“Cross communication is not a function of activity difficulties because we see changes in the brain when people do not move,” Seidler said.
In some diseases where the corpus callosum is severely deteriorated as in people with multiple sclerosis, you can see “twin movements” during one-sided motor activity, where both sides move together because there is a lot of communication between the two hemispheres, Seidler said . The movement of these twins also normally occurs in very young children before the corpus callosum develops perfectly.
In the study, the researchers provided control levers in adults between 65 and 75 and then measured and compared their response times with the 20-25 year age group.
The researchers then used Magnetic Resonance Imaging to map blood oxygen levels in various places in the brain, in other words measurements of brain activity.
“The more they use the other side of the brain, the slower they respond,” Seidler said.
But there is hope, inevitable aging does not mean that it has become our fate to react more slowly. Seidler and his team are working on a study of the development and control of motor exercise that might be able to rebuild or maintain the corpus callosum to limit excessive flow between the two hemispheres, he said.
Previous studies conducted by other teams showed that doing aerobic exercise for three months helped rebuild the corpus callosum , he said, which showed that physical activity could help offset the degenerative effects associated with aging.
Seidler and his team also revised the study using brain mapping techniques to examine diseases associated with brain changes in patients suffering from Parkinson’s disease.
The study was reported in the journal Frontiers in Systems Neuroscience .