To Your Health
Not too long ago scientists believed nerve cells in the body could not regenerate. But recent research indicates not only that nerve cells do regenerate, but in healthy individuals they do so daily. And better yet, there are things we can do to maximize the process.
Much of the information in this month's column comes from a recent ABC Radio interview with Professor Perry Bartlett, Director of the Queensland Brain Institute at The University of Queensland, Australia. The topic was "How To Save Your Brain." According to Professor Bartlett, recent studies done with rodents indicate that antidepressant drugs work by stimulating the growth of new neurons in the brain. This would explain, he says, the fact that antidepressants take about a month to become effective. Before this discovery, it was believed that antidepressants worked by changing brain chemistry. But when scientists blocked the production of new nerve cells, they found that antidepressants like Prozac had no effect. Commenting on this finding, Professor Bartlett says, "That's a fairly dramatic finding, and I think more importantly, it's not so much about the antidepressant, it actually says that perhaps just normal well-being is based on the production of new nerve cells." That is, it may be that depression results when our brains are not producing a sufficient number of new neurons.
So what else stimulates new neuron growth? Apparently many things do. Perry says that each day our brains generate about 10,000 new neurons just in response to smells we encounter in the environment. Many of these new cells die off, while those that survive are "getting appropriate inputs from the environment." I interpret this to mean that when our noses detect a certain smell again, the neurons produced in response to that particular odor are the ones that survive. Professor Perry theorizes that our brains are continually adapting to the outside environment, and that sounds very logical to me.
His theory has not yet been proved, but there is evidence to support it. For instance, he says you can take a rodent out of its little cage and place it in a rich environment where it can run and encounter lots of new experiences, and, as a result, many new neurons will be produced. Again most of those will die within two weeks. But when the rodent continues to receive sufficient stimulation through exposure to new smells, sights, and activities, more of the cells will survive.
How does this apply to our brains? What can we do to stimulate and maintain brain growth? Apparently, the best thing we can do is to seek new experiences and a rich variety of sensual, emotional, and intellectual stimulation. It also helps to get plenty of exercise, another stimulant to brain growth, and you might want to include sexual activity in the mix because, says Perry, "Certain molecules produced during sex also appear to be highly stimulatory of neuronal production." To read the entire interview, go to www.abc.net.au/rn/science/ss/stories/s1121140.htm.
Paulette Avery is a registered nurse and a freelance writer who specializes in health issues.