Birdsong Studies Lead To a Revolution In Biology

Smithsonian.com covers research that began with the study of birdsong and ended by overturning the common belief that adult animals can't produce new brain cells. "Deconstructing birdsong may seem an unlikely way to shake up biology. But [Fernando] Nottebohm's research has shattered the belief that a brain gets its quota of nerve cells shortly after birth and stands by helplessly as one by one they die — a 'fact' drummed into every schoolkid's skull. [Nottebohm] demonstrated two decades ago that the brain of a male songbird grows fresh nerve cells in the fall to replace those that die off in summer. The findings were shocking, and scientists voiced skepticism that the adult human brain had the same knack for regeneration. ... Yet, inspired by Nottebohm's work, researchers went on to find that other adult animals — including human beings — are indeed capable of producing new brain cells. And in February, scientists reported for the first time that brand-new nerves in adult mouse brains appeared to conduct impulses — a finding that addressed lingering concerns that newly formed adult neurons might not function."

Comments

Re:fat cells and muscle cells, too?

[__aasqbs9791]

Blasphemy! Each person only has 1 muscle cell that grows larger as they work out. /s

I learned the same things in school myself. We ere even taught that nerve cells didn't get repaired after they were damaged (to the point of dying). Oh, except in the tongue. Those were unique for some reason. And then we started learning that other nerve cells (like in the spine) did sometimes heal, but that perhaps the 'muscle memory' was lost, and learning to walk when you are an adult is much harder than it was as a child. At some point I think we may just have to say, "We don't know what we think we know, and maybe we should just start all over again." We stand on the shoulders of giants when we discover something new, but apparently sometimes it turns of those are midget's, not giant's shoulders, and we are forced to unlearn something we thought was true. Thus goes the ways of science.

Well, duh.

[pclminion]

I don't mean "duh" to the researcher -- obviously things must be tested and validated in the real world, not just postulated -- but it never made sense to me in the first place that brain cells can't regenerate. Why the hell not? What is the adaptive purpose of such a limitation? The brain consumes a huge amount of energy, much more so per-pound than any other organ in the body. That seems to imply that the brain is extremely important to the organism. Why would essentially the most important organ in the body have such a stupid limitation that it can't even recover from MINOR damage? That makes no sense.

One possible explanation for the very limited growth rate of brain cells is that if this growth rate were not tightly controlled, it could lead to "chaotic" brain tissue which could interfere with normal brain function. So general division of brain cells would not be desirable -- but I'm no neuroscientist.

Re:fat cells and muscle cells, too?

[lennier]

"outdated knowledge"

Isn't that a contradiction in terms? If it's wrong now, it was just as wrong when it was being taught... knowledge doesn't get "outdated". Opinions and beliefs and fashionable ideas may change... but not actual *knowledge*.

Pedantic, I know, but I get creeped out by the subtle assumption that somehow the very foundations of reality change under us as the scientific consensus shifts. This sort of abuse of language and the misidentification of beliefs, teachings and opinions with fact, is exactly why the man in the street has grown to distrust "science".

I'm pretty horrified myself if this "muscle tearing" thing is in fact incorrect - because that's what I was taught in high school gym class. It sounded stupid and abusive to me at the time - why should destroying muscle be a *good* thing? - and it was used to justify the "if it doesn't hurt you're not doing it right" idea. If it turns out that that was a flat lie all along... yeah, I'm pretty pissed off. Shouldn't we hold off making *any* such "scientific" pronouncements until we're darn sure, for good and all, that we're NOT just saying crazy wrong things?