Neuroanatomy, Sympathetic Nervous System

Excerpt

The sympathetic autonomic nervous system (SANS) is one of the two divisions of the autonomic nervous system (ANS), along with the parasympathetic nervous system (PANS), These systems primarily work unconsciously in opposite ways to regulate many functions and parts of the body. Colloquially, the SANS governs the "fight or flight" response while the PANS controls the "rest and digest" response. The main overall end effect of the SANS is to prepare the body for physical activity, a whole-body reaction affecting many organ systems throughout the body to redirect oxygen-rich blood to areas of the body needed during intense physical demand.