NEW HAVEN, Conn., Nov. 5 (UPI) -- U.S. researchers have discovered new neurons in the adult brain get signals from distant brain regions before communicating with older, neighboring neurons.

   The Yale University scientists said the signals guide the maturation of the new neurons, and block their output for up to 10 days.

   The researchers -- Professor Charles Greer and doctoral candidate Mary Whitman -- believe blocking output from new neurons until they have matured facilitates their integration into existing brain circuitry, preventing them from disrupting brain functions.

   Previous studies have shown several regions of the adult brain continue to generate new neurons that are integrated into existing brain circuitry. Greer and Whitman's study demonstrates at least one of the mechanisms that allow that process of integration to happen.

   The finding is significant, said Greer, because "if we want to use stem cells to replace neurons lost to injury or disease, we must ensure that they do not fire inappropriately, which could cause seizures or cognitive dysfunction."

   The study appears in The Journal of Neuroscience.
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