Researchers at Oregon Health & Science University’s Neurological Sciences Institute have uncovered the system that tells the body when to perform one of its most basic defenses against the cold: shivering. The scientists have discovered the brain’s wiring system, which takes temperature information from the skin and determines when a person should start shivering. Their findings are published in the advance online edition of the journal Nature Neuroscience.

“Shivering, which is actually heat production in skeletal muscles, requires quite a bit of energy and is usually the last strategy the body uses to maintain its internal temperature to survive in a severe cold environment.