Think achy joints are the main reason we slow down as we get older? Blame the brain, too: The part in charge of motion may start a gradual downhill slide at age 40. How fast you can throw a ball or run or swerve a steering wheel depends on how speedily brain cells fire off commands to muscles. Fast firing depends on good insulation for your brain's wiring.
Now new research suggests that in middle age, even healthy people begin to lose some of that insulation in a motor-control part of the brain - at the same rate that their speed subtly slows.
That helps explain why "it's hard to be a world-class athlete after 40," concludes Dr. George Bartzokis, a neurologist at the University of California, Los Angeles, who led the work.
"We knew at some age you peak and there's a sense it would disintegrate as you grow older. But we didn't have a sense of where that age would be," says Arvanitakis, who next wants to see if myelin and cognitive functions show a similar trajectory.
Bartzokis' research supports a recent report from German scientists, that with age comes a weakening of the system that's supposed to repair broken myelin, adds Dr. Bradley Wise of the National Institute on Aging.
"Any disruption in these neural circuits and networks will have problems for functioning," says Wise, who says the two reports are spurring increased interest into myelin's role in aging. Until recently, most myelin research has focused on multiple sclerosis, where myelin doesn't gradually degrade but disappears.
Now new research suggests that in middle age, even healthy people begin to lose some of that insulation in a motor-control part of the brain - at the same rate that their speed subtly slows.
That helps explain why "it's hard to be a world-class athlete after 40," concludes Dr. George Bartzokis, a neurologist at the University of California, Los Angeles, who led the work.
"We knew at some age you peak and there's a sense it would disintegrate as you grow older. But we didn't have a sense of where that age would be," says Arvanitakis, who next wants to see if myelin and cognitive functions show a similar trajectory.
Bartzokis' research supports a recent report from German scientists, that with age comes a weakening of the system that's supposed to repair broken myelin, adds Dr. Bradley Wise of the National Institute on Aging.
"Any disruption in these neural circuits and networks will have problems for functioning," says Wise, who says the two reports are spurring increased interest into myelin's role in aging. Until recently, most myelin research has focused on multiple sclerosis, where myelin doesn't gradually degrade but disappears.
http://www.physorg.com/news144948216.html
