Brain's Darwin Machine

[papau]

MAPPING THE MIND

One in a series of occasional articles about scientists' efforts to explore the creation of beliefs and behavior in the synapses of the brain. To read previous articles in this series, go to latimes.com/mind. For an archive of Column One articles, visit latimes.com/columnone.

Does a peculiar string of biochemicals cause the billions of neurons in each person's brain to develop in distinctly different ways, so that even identical twins could develop minds of their own?

http://www.latimes.com/news/science/la-sci-neuron11apr11,0,7081426.story?track=tottext

From the Los Angeles Times
COLUMN ONE
Brain's Darwin Machine
Scientists find evidence of a perpetual evolutionary battle in the mind. The process, they suspect, is the key to individuality.
By Robert Lee Hotz
Times Staff Writer

April 11, 2006

LA JOLLA, Calif. — <snip>Together, the couple stalked an elusive sequence of DNA hidden in the heredity of every human cell. The wayward strand appeared to seek out developing brain cells and, like a virus, arbitrarily alter their genetic makeup.

In this way, it might be partly responsible for the infinite variety of the mind.

In debates over creationist doctrines, evolutionary biologists often are hard-pressed to explain how nature could make something as intricate as the human brain. Even Alfred Wallace, the 19th century biologist who discovered natural selection with Charles Darwin, could not accept that such a flexible organ of learning and thought could emerge by trial and error.
<snip>

Perhaps the sequence, striving for its own survival inside the growing neuron, made the brain more responsive to changing circumstances. Had natural selection seized on the one rogue sequence most useful for crafting an infinitely adaptable human brain?

"There are subtle differences in everything we do throughout our lives," Gage said. "Maybe this is how we generate a deeper adaptability to deal with the unexpected.

"We believe the sequence is generating this diversity to fine-tune the brain."

*

[bemildred]

1. Very interesting.

It is the only way we know to make really complicated things, you need a source of variation and a source of selection, like in evolution. Even chaos of the mathematical variety is "simple" compared to biological organisms.

But they need to come up with a selection mechanism to nail it down. How do the "unfit" neurons get weeded out?

[papau]

2. Perhaps the plaque that hurts in old age is useful in youth as a shut off

of "unfit" neurons?

Sometimes I wish I was in research - but then I realize these folks are smarter than myself and do not need me to save the world - or even to make the next discovery!

:toast:

:-)