The autonomic nervous system is the part of the body that controls vital functions such as heartbeat, blood pressure, bowels and bladder, temperature control, and sweating. These are involuntary processes – that is, we don’t have to think about them, because they happen automatically. There are two parts of the autonomic nervous system, the sympathetic and parasympathetic arms.  The sympathetic component coordinates a ‘fight or flight’ response to a possible threat, like running away from an attacker. The ‘parasympathetic nervous system’ coordinates a ‘rest and digest’ response required for us to rest, repair, digest our food and expel waste products.

Many bodily functions are controlled by the autonomic nervous system. These include the heart, lungs, bladder, gut, muscles, skin and even the pupils in your eyes!