WHAT WAS THAT AGAIN?: A study led by a group at Harvard determined that degradation of white matter pathways that connect different brain regions may be behind fading memory associated with aging.
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As we age, it becomes harder and harder to recall names, dates—even where we put down our keys. Although we may fear the onset of Alzheimer's, chances are, our recollective powers have dulled simply because we're getting older—and our brains, like our bodies, are no longer in tip-top shape.
But what is it that actually causes memory and other cognitive abilities to go soft with senescence? Previous research has shown that bundles of axons (tubular projections sent out by neurons to signal other nerve cells) wither over time. These conduits, collectively referred to as white matter, help connect different regions of the brain to allow for proper information processing.
Now, researchers have found that these white matter pathways erode as we age, impairing communication or "cross talk'' between different brain areas.
"What we were looking at was the communication or cross talk between different regions of the brain," says study co-author Jessica Andrews-Hanna, a Harvard University graduate student. "The degree to which white matter regions are actually stable predicts the degree to which other regions are able to communicate with each other."
Andrews-Hanna and other Harvard researchers (along with collaborators at the University of Michigan at Ann Arbor and Washington University in St. Louis) concluded that white matter naturally degrades as we age—causing disrupted communication between brain regions and memory deficits—after conducting a battery of cognitive tests and brain scans on 93 healthy volunteers, ages 18 to 93. Participants fell into two age groups: one 18 to 34 and the other 60 to 93 years of age.
Scientists asked study subjects to perform several cognitive and memory exercises, such as determining whether certain words referred to living or nonliving objects. As they answered, researchers monitored activity in the fronts and backs of their brains with functional imaging magnetic resonance imaging (fMRI) to determine whether those areas were operating in sync. The results, published in Neuron: communication between brain regions appeared to have "dramatically declined" in the older group.
They fingered the potential reason for the dip by doing further brain scans using diffusion tensor imaging, an MRI technique that gauges how well white matter is functioning by monitoring water movement along the axonal bundles. If communication is strong, water flows as if cascading down a celery stalk, says Randy Buckner, a cognitive neuroscientist at Harvard; if it is disrupted, the pattern looks more like a drop of dye in a water bucket that has scattered in all directions. The latter was more evident in the older group, an indication that their white matter had lost some of its integrity.
The older crowd's performance on memory and cognitive skill tests correlated with white matter loss: The seniors did poorly relative to their younger peers. The researchers note that the white matter appears to fray more over time in the forebrain than in the brain's rear. They speculate that age-related depletion of neurotransmitters (the chemical signals sent between neurons) as well as the shrinking of gray matter (the tissue made up of the actual nerve cell bodies and supporting cells) also contribute to dimming memory and cognitive skills.
Buckner says that the team now plans to examine how aging affects white matter as well as gray matter and neurotransmitters. "We want to know," he says, "is this an important factor in why some people age gracefully and others age less gracefully?"
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17 Comments
Add Commentdamn, I was gonna write something, but now I can't remember what it was...
Reply | Report Abuse | Link to thisI am going to guess that another thing that destabilizes neural communication is stress, perhaps because it introduces noise into the system. This noise makes nerves jittery, so more responsive to slight stimulus, but it degrades the quality of signals. Long-term stress can cause changes in the brain that keep adding signal noise, even when not appropriate.
Reply | Report Abuse | Link to thisThe article doesn't mention if the study was broken down for intragroup variables such as the effects of quantity and quality of mental use on memory loss, because if there was a correlation then can the brain, like the body, stave off aging for a time, by exercising mental function.
Reply | Report Abuse | Link to thisIt would be interesting to know if those who are most mentally active have reduced loss of white matter, and disrupted communication between brain regions with age.
Reply | Report Abuse | Link to thisIs there anything one can do to reduce the loss of mental facility?
Reply | Report Abuse | Link to thisWill taking anti-depressant affect this process?
Reply | Report Abuse | Link to thisI am assuming you gentlemen are researching on how to prevent this age brain activity loss. Would love to see a break through. I have a relative who is suffering from such.
Reply | Report Abuse | Link to thisInteresting that they can visualize the loss of neurotransmission along the axon. A little more information is hoped for that in future studies may give us prevention methods.
Reply | Report Abuse | Link to thisThere appears to be quite a bit of information out there about how to prevent age related declines. Most importantly it seems to say exercise and healthy diet that promote blood flow to the brain and all vital organs seem to help. This includes habits of eating and exercise that reduce or prevent the buildup of plaques on all arteries. This has beneficial effects of in the brain as well as the heart and kidneys...etc. A healthy diet low in saturated fats as in fish and white meat, antioxidants as in fruits and vegetables and keeping weight at a reasonable level... Also fish oils and the right combination of omega fats. This much we do seem to know.
Reply | Report Abuse | Link to thisis aging a punishment for the great stupidity we are all powerless from?
Reply | Report Abuse | Link to thisis there anything that can slow the deterioration? Doesn't sound like doing cross-word puzzles will help..
Reply | Report Abuse | Link to thisCan physical exercise and yoga or may be even breathing exercises like hyperventilation slow down this deterioration? Can herbal extracts like ginseng help?
Reply | Report Abuse | Link to thisAlzheimers is not probably a disease but an initiative of an individuals subconscious mind. We all have a past and that past is influenced by decisions, happenings, occurrences, events, possibly with or without our consent or conscious decision.
Reply | Report Abuse | Link to thisDuring the period of growth from childhood to late adulthood these occurrences get registered into memory and the same faculty in manner of a Loop is activated repeatedly (which we might refer as Recall) as a result of probably millions of interactions in an individuals life, some even referring to déjà vu. While recall might get initiated, it necessarily does not insure invoking a good or bad feeling inside a persons mind, meaning some memories are better forgotten .
The result of recall and further actions initiated by the individual to savor or dismiss the recall is the start for Alzheimers. There is enough proof of mind over matter and the control of mind and its functions by practice. This practice, to have an effect, takes time to mature into sturdy results i.e. probably middle-age in individuals.
The question to be probed is whether we should investigate the power within an individual to SUB-CONCIOUSLY ERASE MEMORY or some tissue damage that leads to such erasure.
Please notice that people who are inflicted with Alzheimers are not the real victims but people around them. They are probably happy in a dead memory, a stage they have probably achieved with much effort and inducement.
Dias Joseph Kurian
diaskurian@gmail.com
India. +91 9811711206
ON i cant spil when i write,so what to do?
Reply | Report Abuse | Link to thisI CANT SPIL?
Reply | Report Abuse | Link to thisI would like to know how to increase such white matter in my head,fighting for exams~~~
Reply | Report Abuse | Link to thisWhile there is no 'cure' for aging, studies have shown that exercise helps to keep memory strong. The daily use of the brain in general (reading, doing crossword puzzles, etc.) has also been linked to strengthening the connections in the brain.
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