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Mapping the Human Brain in 3D

Neurologist Kristen Harris has spent the past few years working to do just that. She and a team of postdoctoral researchers have been dissecting, imaging and digitally recreating a highly detailed, three-dimensional map of the human brain.

The process involves taking a small chunk of brain matter, slicing it thin enough to be viewed beneath a microscope and then using the information gleaned from each individual slide to reconstruct a 3D picture of the brain's interior sections.

Harris demonstrated her results, a complex 3D model of a small square of brain tissue, at the World Science Festival in New York City, at a panel entitled "Architects of the Mind.This example section, which contains around 500 synapses, took Harris and her team several years to model. It's also smaller than a single red blood cell — less than 200 cubic microns."It's so tiny that if we were going to map the entire human brain at that level, we would have to repeat [this process] billions of times over," Harris explained.

Mapping the human brain is "an enormous challenge," neurologist R. Douglas Fields agreed, also speaking at the panel. "We've always tended to try to understand it in terms of analogies to the most current technology of the time … mechanics or hydraulics. Today we tend to think of the brain in terms of an electrical computer. It's humbling to think that the brain might not [work like] that at all."

Cognitive roboticist Murray Shanahan added, "It's probably right to say the brain isn't like a computer. Nevertheless, we can build computers that are like brains, which is a very different kind of thing." Computers are also the best tools available for learning about the brain, but even the best computers are still only capable of agonizingly slow progress.

Glial Cells                                                                          

Harris's model is further complicated because scientists have yet to discover the exact functions of the structures she is so painstakingly mapping.

Among the most mysterious are glial cells, which surround and support neurons. These support cells are among the most numerous cells in the brain; Fields, whose work focuses on glial cells, calls them the "background" of the brain, the "glue" that holds the neurons together.

Glia reveal one of the main ways that the brain's functioning differs from a computer's. These cells are decentralized; they don't function with electricity, and yet they seem to play a significant role in brain function, providing far more than mere padding for the neurons.

Why this revolutionary research?

Given the immense challenges involved in creating computer representations of a brain, and possibly even the futility of the attempt, why even try? There are 2 possible reasons 

One is the scientific motivation. If we properly understand how [the brain] works, then we ought to be able to simulate it on our computer. We ought to be able to build computer models of it. Moreover, if we're able to build computer models, then that will help us understand it.The second reason is to aid in the development of artificial intelligence. By building models of the brain and understanding better how the brain works, then we might be in a position to build artifacts that have intelligence as we do.

Discussions of artificial intelligence often take a turn for the ethical and hypothetical, and "Architects of the Mind" was no different. This research will widen the horizon of building robots with greater intelligence than humans.

True artificial intelligence is even further off than a working model of the human brain, but with each new development, it becomes more and more feasible that these ideas, once firmly in the realm of science fiction, could become reality within this century.

 

Sources - http://www.technewsdaily.com/18297-architects-of-the-mind.html