Post by John A. Casler on Nov 9, 2008 8:38:01 GMT -8
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As posted to SuperTraining by Jamie Carruthers
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Study: Brain slows at 40, starts body decline
Nov. 3, 2008 01:11 PM
Associated Press
WASHINGTON - 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 UCLA, who led
the work.
And while that may sound depressing, keep reading. The research
points to yet another reason to stay physically and mentally active:
An exercised brain may spot fraying insulation quicker and signal for
repair cells to get to work.
To Bartzokis, the brain is like the Internet. Speedy movement depends
on bandwidth, which in the brain is myelin, a special sheet of fat
that coats nerve fibers.
Healthy myelin - good thick insulation wound tightly around those
nerve fibers - allows prompt conduction of the electrical signals the
brain uses to send commands. Higher-frequency electrical discharges,
known as "actional potentials," speed movement - any movement, from a
basketball rebound to a finger tap.
Consider someone like Michael Jordan. "The circuitry that made him a
great basketball player was probably myelinated better than most
other mortals," Bartzokis notes.
But while myelin builds up during adolescence, when does production
slow enough that we fall behind in the race to repair fraying, older
insulation?
Enter the new research. First, Bartzokis recruited 72 healthy men,
ages 23 to 80, to perform a simple test: How fast they tapped an
index finger. Anyone can do this; it doesn't depend on strength or
fitness.
Researchers counted how many taps the men made in 10 seconds,
recording the two fastest of 10 attempts. Then, brain scans checked
for myelin in need of repair in the region that orders a finger to
tap.
Strikingly, tapping speed and myelin health both peaked at age 39.
Then both gradually declined with increasing age, the researchers
reported last month in the journal Neurobiology of Aging.
That doesn't mean the rest of the brain is equally affected.
Bartzokis has some evidence that myelin starts to fray a decade or so
later in brain regions responsible for cognitive functions - higher-
level thinking - than in motor-control areas.
So back to his example of Jordan, who last played professionally at
age 40: "Even he started getting older. That circuitry started
breaking down a little," contends Bartzokis. "He can become Michael
Jordan the big-shot businessman ... but not be Michael Jordan the
super-duper basketball player anymore."
Bartzokis isn't looking to build a better athlete. His ultimate goal
is to fight Alzheimer's disease. The connection: Building memories
requires high-frequency electrical bursts, too, and Bartzokis'
earlier research suggests an Alzheimer's-linked gene may thwart
myelin repair.
But the new research has broader implications because it sheds light
on normal aging, says Dr. Zoe Arvanitakis, a neurologist at Chicago's
Rush University Medical Center.
"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.
While much more research is needed, Bartzokis has some practical
advice:
-Keeping active and treating high blood pressure, high cholesterol
and diabetes already are deemed important for good brain health. But
physical and mental activity also may stimulate myelin repair, while
unused neural pathways wouldn't send out a "help" signal, he says.
"Remember, these are average people I tested," Bartzokis
says. "Someone that's really practicing could make it (myelin) last
longer because you're sending the signals to repair, repair, repair."
-Stress hormones, however, may hurt myelin.
-He's also testing whether consumption of omega-3 fatty acids - the
oils, found in fatty fish, already recommended for cardiovascular
health - might help maintain myelin.
========================
Jamie Carruthers
Wakefield, UK
========================
As posted to SuperTraining by Jamie Carruthers
========================
Study: Brain slows at 40, starts body decline
Nov. 3, 2008 01:11 PM
Associated Press
WASHINGTON - 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 UCLA, who led
the work.
And while that may sound depressing, keep reading. The research
points to yet another reason to stay physically and mentally active:
An exercised brain may spot fraying insulation quicker and signal for
repair cells to get to work.
To Bartzokis, the brain is like the Internet. Speedy movement depends
on bandwidth, which in the brain is myelin, a special sheet of fat
that coats nerve fibers.
Healthy myelin - good thick insulation wound tightly around those
nerve fibers - allows prompt conduction of the electrical signals the
brain uses to send commands. Higher-frequency electrical discharges,
known as "actional potentials," speed movement - any movement, from a
basketball rebound to a finger tap.
Consider someone like Michael Jordan. "The circuitry that made him a
great basketball player was probably myelinated better than most
other mortals," Bartzokis notes.
But while myelin builds up during adolescence, when does production
slow enough that we fall behind in the race to repair fraying, older
insulation?
Enter the new research. First, Bartzokis recruited 72 healthy men,
ages 23 to 80, to perform a simple test: How fast they tapped an
index finger. Anyone can do this; it doesn't depend on strength or
fitness.
Researchers counted how many taps the men made in 10 seconds,
recording the two fastest of 10 attempts. Then, brain scans checked
for myelin in need of repair in the region that orders a finger to
tap.
Strikingly, tapping speed and myelin health both peaked at age 39.
Then both gradually declined with increasing age, the researchers
reported last month in the journal Neurobiology of Aging.
That doesn't mean the rest of the brain is equally affected.
Bartzokis has some evidence that myelin starts to fray a decade or so
later in brain regions responsible for cognitive functions - higher-
level thinking - than in motor-control areas.
So back to his example of Jordan, who last played professionally at
age 40: "Even he started getting older. That circuitry started
breaking down a little," contends Bartzokis. "He can become Michael
Jordan the big-shot businessman ... but not be Michael Jordan the
super-duper basketball player anymore."
Bartzokis isn't looking to build a better athlete. His ultimate goal
is to fight Alzheimer's disease. The connection: Building memories
requires high-frequency electrical bursts, too, and Bartzokis'
earlier research suggests an Alzheimer's-linked gene may thwart
myelin repair.
But the new research has broader implications because it sheds light
on normal aging, says Dr. Zoe Arvanitakis, a neurologist at Chicago's
Rush University Medical Center.
"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.
While much more research is needed, Bartzokis has some practical
advice:
-Keeping active and treating high blood pressure, high cholesterol
and diabetes already are deemed important for good brain health. But
physical and mental activity also may stimulate myelin repair, while
unused neural pathways wouldn't send out a "help" signal, he says.
"Remember, these are average people I tested," Bartzokis
says. "Someone that's really practicing could make it (myelin) last
longer because you're sending the signals to repair, repair, repair."
-Stress hormones, however, may hurt myelin.
-He's also testing whether consumption of omega-3 fatty acids - the
oils, found in fatty fish, already recommended for cardiovascular
health - might help maintain myelin.
========================
Jamie Carruthers
Wakefield, UK