Brain complexity: a review (Introduction)

by David Turell , Wednesday, October 07, 2015, 14:16 (3335 days ago) @ David Turell

This magazine offers many articles on brain complexity. Worth a look:-http://www.the-scientist.com//?articles.view/articleNo/44085/title/Special-Delivery/-"It's hard to wrap one's mind around the human brain. With its 86 billion neurons, even greater numbers of glial cells, a quadrillion synapses, and millions of miles of axons, this intricate organ doesn't readily reveal its inner workings. But its complexity hasn't kept researchers from striving to sort out the details of the brain's form and functions.-***-"In our annual issue dedicated to neuroscience, two features describe such dogma-busting research. Neuroscientist Margaret McCarthy debunks the idea that male and female brains differ only in brain areas related to reproduction in “Sex Differences in the Brain.” Certain areas of male and female noodles differ significantly from fetal development right on through adolescence and into adulthood, and McCarthy explains that it's not just the neuronal connections; the behavior of glial cells also differs between the sexes. The upshot is that research on brain function must include female as well as male subjects to fully understand the importance of such differences.-"Another long-held belief that has bitten the dust in the last few decades is that adult human brains do not generate new neurons. True, most of our lifetime supply of neurons is produced before birth; they proliferate, in fact, so overexuberantly in the fetal brain that half of them die before we are born. As people age they continue to lose neurons, albeit at a far slower rate. But even as the adult brain loses neurons, we now know, it also gains new ones. In “Brain Gain,” Senior Editor Jef Akst reports on the role played by these new neurons, which are especially prominent in the hippocampus, a brain region vital to learning and memory. As one investigator puts it: “We think that [adult] neurogene­sis provides a way, a mechanism of living in the moment. . . . It clears out old memories and helps form new memories.'”