From Wired News: New Neurons Work in an Old Brain describes a letter published today in Nature which gives the lie to the old notion that you have a finite number of brain cells given at birth, and that as they die off you are doomed to an increasingly limited supply.
The topic of neurogenesis has been hotly debated; there was a fascinating article about it in The New Yorker awhile back (unfortunately, their website doesn't provide any search mechanism, and they don't appear to have brought past issues into an online archive, so I can't point to it). Sadly, I can't remember which researcher was profiled in that piece (can you say 'dead brain cells'?), someone who has been jumping up and down and yelling "The brain DOES TOO make and use new cells!" and getting slapped silly by the neuroscience mainstream on a regular basis -- but it certainly looks as if he or she's likely to be vindicated by follow-up on this latest research on mice. Even the scientist whom the New Yorker's profile identified as the prime stick-in-the-mud on this topic, Yale's Pasko Rakic, seems to be convinced.
What's more, one reason the old dog may learn the new tricks is because it gets him off his big fat doggy duff. Other human research has shown that regular physical exercise delays or rolls back the onset of senility (cognitive impairment is the technical term, I believe) in older folks. And the main author of the Nature letter points out that the more physically active mice got the most new neurons.
So I suppose I better start doing something about my unbelievably sedentary lifestyle.
As a person of *ahem* a meaningful accumulation of years, all I can do is bow in awe before anyone who at age 39 retains the fire and talent to be one of the best in an extremely demanding sport.
Write to me!
