Here’s a quick review of anatomy and physiology.
The autonomic nervous system includes the parasympathetic and sympathetic systems. We tend to think of the parasympathetic and sympathetic systems as competing each other. Their purpose is to maintain a stable internal environment by coordinating, adjusting and regulating the body’s visceral activity.
We’re looking at things that are NOT voluntary, such as controlling your digestion, body temperature, heart rate and so forth. The primary function of the ANS is to maintain homeostasis.
Parasympathetic Division
- The parasympathetic nerves anatomically come out of the cranio-sacral region of the spine.
- Its purpose is meant to store and conserve energy.
- In physiology we learned this colloquially as the rest & digest system.  So what would happen to the heart rate? It would slow it down. It would speed up digestion.
Sympathetic Division
- The sympathetic nerves anatomically come out of the thoraco-lumbar region of the spine.
- The sympathetic system prepares the body for stress and emergency.
- In physiology we learned this as the fight/flight sequence so it gets the heart pumping more. It’s also involved in non-stress regulation such as sweat and the eyes which we will look into further.
