Mimicking the Brain: Using Computers to Investigate Neurological Disorders

Seachrist, Lisa, Science News

Deep within the brain a single neuron fires. That electrical signal

triggers a biochemical chain reaction that courses from neuron to neuron, ultimately forming a set of connections that brings alive a scenic vista, a child's touch, or the memory of a long-ago event. Arresting any part of that signal devastates the cognitive activities that appear to make us human.

While the speed and precision of the human brain lead some people to refer to it as the ultimate computer, the brain maintains a distinct advantage over the computer--resilience. When crucial interactions between neurons falter, the brain reroutes signals in an attempt to maintain the ability to think, remember, and perceive. "When you damage just one small part of the computer, the whole thing will collapse," says neurologist and computer scientist James Reggia of the University of Maryland in College Park. "The brain is very different. It is able to adjust its own circuitry."

Despite this resilience, the brain has its limitations. Neurological diseases such as Alzheimer's and Parkinson's cause progressive losses of vital cognitive functions that no degree of brain-initiated rewiring can repair.

Scientists do not know why some conditions spur the brain to large-scale reorganization of the synapses, or junctions between neurons, whereas others result in permanent damage. The problem lies in a basic dichotomy in neuroscience: Remarkable gains in elucidating the way neurons communicate with each other on the molecular level simply haven't explained the biology of how we think, sense, and feel.

For the past decade, researchers have employed a controversial tool to decipher this puzzle: computer systems known as neural networks. These networks simulate elementary, but poorly understood, brain functions such as reading and …

Questia, a part of Gale, Cengage Learning. www.questia.com
Publication information: Article title: Mimicking the Brain: Using Computers to Investigate Neurological Disorders. Contributors: Seachrist, Lisa - Author. Magazine title: Science News. Volume: 148. Issue: 4 Publication date: July 22, 1995. Page number: 62+. © 2009 Science Service, Inc. COPYRIGHT 1995 Gale Group.

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