Cortisol -- your “fight-or-flight” hormone -- is designed to let you know when you’re danger. But too much or too of it can throw your whole body out of whack. Learn why.| WebMD
The autonomic nervous system is a component of the peripheral nervous system that regulates involuntary physiologic processes including heart rate, blood pressure, respiration, digestion, and sexual arousal. It contains three anatomically distinct divisions: sympathetic, parasympathetic, and enteric.| www.ncbi.nlm.nih.gov