Brain: Use it or lose it:
the choice is yours
A recent study suggests that those who keep their brain cells active through all stages of life are able to keep dementia at bay
As any athlete worth his salt would confirm, regardless of the tone and strength of muscular power one may have, the moment one stops working on them, they tend to convert into flab. Not much is different in the case of brain power. A recent study in the UK has once again confirmed the link between mental inactivity and dementia — a disease resulting in memory loss, lack of motivation, mood swings, an inability to solve simple problems and disorientation which entails getting lost even in otherwise familiar places.
The research was conducted at King’s College London’s Institute of Psychiatry, where experts studied 1,320 patients suffering from dementia. They found that the onset of the disease was delayed among those who worked until later in life. In scientific parlance, keeping one’s mind active entails building up cognitive reserves which, in turn, keep at bay any large-scale loss of cells in the brain. According to an expert, continuing to work after age 65 clearly means more mental stimulation, and each year of additional work after normal retirement age leads to a six-week delay in the onset of dementia.
The bottom line is quite clear for the layperson, but it is quite fascinating to have a quick look at the baffling body cells and the difference they have with brain cells. Life in all forms starts with a single cell. The first cell splits to become two and the two become four. After just 47 doublings, one gets 10,000 trillion — or ten quadrillion — cells in a body which then gets ready to be dubbed as a human being.
Since a number of cells are lost in the process of development, the final number at best remains an intelligent guess. However, these are not particularly intelligent guesses as they vary from scientist to scientist. The ten quadrillion figure is estimated by renowned theoretical biologist and professor of botany at the University of Massachusetts, Lynn Margulis, whose research on the evolutionary links between cells led her to formulate a symbiotic theory of evolution that was initially spurned in the scientific community, but has become more widely accepted now.
Regardless of the numbers, every cell is an object of wonder. To build the most basic yeast cell, which is nothing in terms of complexity compared to the human cell, one has to miniaturise about the same number of components as are found in a modern jetliner.
On an average, a cell is about 20 microns wide — which is roughly the two hundredth part of a millimetre. Too small? Indeed it is, but it is still large enough to hold thousands of complicated structures like mitochondria and millions of molecules. When blown up to a scale at which atoms are about the size of peas, a cell itself would be a sphere about half-a-mile across and supported by a complex framework of girders called the cytoskeleton. Within the cell there are millions upon millions of objects — some about the size of a basketball, others about that of a car — whizzing like bullets.
It’s a busy place where nothing can stand idle without being pummelled, hit and scratched by something or the other because there is so much moving around in a never-ending whirl of a motion. Even for its fulltime occupants, the DNA, the cell is a hazardous place because each strand is attacked on an average every 8.4 seconds, which is more than 10,000 times a day, by chemicals and other agents. Each of these wounds must be swiftly stitched up if the cell is not to perish.
It is no wonder, then, that most living cells seldom last more than a month or so. But before they perish, there are always others ready to replace them and that keeps life moving and when there are not enough ready in the bank, the process of being comes to an end. Simple, you see.
However, there are some notable exceptions: liver cells, for instance, can survive for years though the components within them continue to get renewed every few days. Brain cells, on their part, last as long as one survives. Scientists believe that every human being is issued with a set of about a hundred billion brain cells at birth and that is a fixed quota for the rest of one’s life.
Adding to the fun part is the fact that humans lose about five hundred cells from that quota about every hour. The redeeming factor is that, like the liver cells, components within the brain cells keep getting renewed. A fully functional brain will have no cell component older than a month. Stop using it and the pace of regeneration gets slower, leading to memory loss and ultimately to dementia. It is infinitely better to use it than to lose it. The choice is yours.
[By Aaich Aa’yee, Dawn, Sunday, 31 May, 2009]-----------------------------------------