http://news.nationalgeographic.com/news/2008/07/080709-Special cells in the brain allow animals to overcome fear and anxiety by recalling memories of similar situations when they were unafraid, according to new research.
The finding could lead to new drugs for helping people with anxiety-related conditions such as post-traumatic stress disorder, scientists say.
Previous work had suggested that a part of the brain called the amygdala—an almond-shaped mass of cells deep in the brain—plays an important role in this process, known as fear extinction.
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Researchers for years have had difficulty determining which of the dozen or so clusters of cells that make up the amygdala is directly responsible.
Now, using a technique that selectively eliminates brain cells, neuroscientist Denis Paré and colleagues have revealed that cells called intercalated (ITC) neurons are crucial for overcoming fear.
"The available data indicates that one does not unlearn fear but instead learns not to fear the threatening stimulus in particular contexts," said Paré, of Rutgers University in New Jersey.
as usual, this could be for good or for evil.