When danger lurks, instinct keeps us safe. It compels us to run from a burning building or wrestle a knife-wielding attacker to the ground. It also adjusts our body physiology to support these behaviors.

Survival helps explain why. But the mechanisms that link the brain and the body—the “switch” between rest and action—have long been shrouded in mystery.

A research team at Rutgers University-New Brunswick thinks they may have identified a key mechanism, and the findings may hold important clues to how diverse neurological conditions, such as alcohol use disorder and Parkinson’s, could be diagnosed and treated.