Known as the wanderer, the vagus nerve, or cranial nerve X (10), is a long nerve that runs from the cranium to the colon, connecting and controlling all the organs in between. The vagus nerve is the main component of the parasympathetic nervous system, which oversees a vast array of crucial bodily functions, including control of mood, immune response, digestion, heart rate, and more.
The parasympathetic nervous system is also known as the rest and digest response because it restores the body back into balance after sympathetic stimulation, or fight-or-flight response. When the body is in a sympathetic state, its primary focus is stress and being able to flee from a situation, if necessary. In a parasympathetic state, the body is calm and composed and is able to focus on resting and digesting.
