From Primitive Parts, A Highly Evolved Human Brain
by JON HAMILTON
Courtesy of the Allen Institute for Brain Science
The dark regions of this section of a human brain are areas dense with nerve cell bodies, while the white regions are the areas where the neural fibers run, connecting one brain area to another. The structures seen in the middle are evolutionarily "older"; the wrinkly outer portions and associated white matter are more recent and differentiate us from lower mammals.
August 9, 2010
From one perspective, the human brain is a masterpiece. From another, it's 3 pounds of inefficient jelly. Both views are accurate, and that's because our remarkable brain has been assembled from some very primitive parts.
"Although the things it can do are very wonderful and impressive, its design is very poor engineering in many respects," says David Linden, a professor of neuroscience at Johns Hopkins University in Baltimore.
Linden says there's a simple explanation: evolution.
Courtesy of the Allen Institute for Brain Science
The colors in this 3D rendering of a human brain represent different regions of the cortex, the wrinkly outer part of the brain that contains the most evolutionarily advanced regions.
"In evolution, you never build something new if you can adapt something you've already got," he says. "It's the ultimate tinkerer and the ultimate cheapskate."
Our brain has been put together with parts from jellyfish and lizards and mice, Linden says. These parts may have been OK for their original owners, he says, but they aren't ideal for us.
Take brain cells, for example.
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Read more here/Leia mais aqui: NPR
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