Light Switches Brain Pathway On-and-Off to Dissect How Anxiety Works
Scientists, for the first time, have switched anxiety on-and-off in active animals by shining light at a brain pathway. Instinctively reclusive mice suddenly began exploring normally forbidding open spaces when a blue laser activated the pathway – and retreated into a protected area when it dimmed. By contrast, anxiety-like behaviors increased when an amber laser inhibited the same pathway.
Researchers, supported in part by NIMH, used a virus, genetic engineering and fiber-optics to control the pathway in the brain’s fear center with millisecond precision.
“Our findings reveal how balanced antagonistic brain pathways are continuously regulating anxiety,” explained Karl Deisseroth, M.D., Ph.D., of Stanford University, a practicing psychiatrist as well as a neuroscientist. “We have pinpointed an anxiety-quelling pathway and demonstrated a way to control it that may hold promise for new types of anti-anxiety treatments.”
NIMH grantees Deisseroth, Kay M. Tye, Ph.D., and colleagues, report on their findings March 17, 2011 in the journal Nature.