Scientists see brain's ability to 'rewire' itself after damage, disease

When the brain's primary "learning center" is damaged it can rewire itself, creating new neural circuits to compensate for lost functions, U.S. researchers say.

Scientists at UCLA, working with colleagues in Australia, say they've been able to pinpoint the regions of the brain involved in creating those alternate pathways, which are often far from the damaged site.

The finding that parts of the prefrontal cortex can take over when the hippocampus, the brain's key center of learning and memory formation, is disabled -- dubbed neural-circuit plasticity -- could potentially help scientists develop new treatments for Alzheimer's disease, stroke and other conditions involving damage to the brain, a UCLA release said Thursday.

Laboratory experiments with rats identified significant functional changes in two specific regions of the prefrontal cortex after damage to the hippocampus.

"Interestingly, previous studies had shown that these prefrontal cortex regions also light up in the brains of Alzheimer's patients, suggesting that similar compensatory circuits develop in people," neuroscience researcher Bruce Vissel of the Garvan Institute of Medical Research in Sydney said.

"While it's probable that the brains of Alzheimer's sufferers are already compensating for damage, this discovery has significant potential for extending that compensation and improving the lives of many."

The hippocampus, which plays critical roles in processing, storing and recalling information, is highly susceptible to damage through stroke or lack of oxygen and is critically involved in Alzheimer's disease, UCLA's Michael Fanselow said.

"Until now, we've been trying to figure out how to stimulate repair within the hippocampus," he said. "Now we can see other structures stepping in and whole new brain circuits coming into being."