he autonomic nervous system (ANS) is the system that controls the majority of involuntary or ‘automatic functions of the body.  AUTONOMIC = AUTOMATIC “The autonomic nervous system regulates the body’s responses without consciously thinking such as breathing, heart rate, blood pressure, digestion, sexual arousal & many other biochemical processes.  The autonomic nervous system sends signals through nerves pathways to control & regulate most organ function such as the heart, lungs, kidney’s etc.  The autonomic nervous system is a very complex system of nerves starting in the brain and sent via the spinal cord through peripheral nerves that extend to all parts of the body.” There are two distinct divisions of the autonomic nervous system. These branches are known as the parasympathetic and the system sympathetic system.  Parasympathetic System “The Parasympathetic System is commonly associated with the “rest and digest” responses – those bodily actions needed to restore energy and rest the body. For example, chewing food triggers the Parasympathetic Nervous System to increase production of saliva and to increase digestion in the gut. The Parasympathetic System also increases gallbladder function, which assists in the digestive process.” Sympathetic System The Sympathetic System is commonly associated with the “fight or flight” responses – those bodily reactions that you need to respond quickly in an emergency. When faced with a life threatening situation, your human instinct takes over and you either fight the danger you are facing, or you take flight and run away from the danger. Your Sympathetic System allows your body to do this rapidly. For example, in the face of danger, your Sympathetic System will cause bronchial dilation – this allows you to breathe better while you are fighting or running away from the dangerous situation. Likewise, your heart will beat stronger and faster, also prepping the body to fight or take flight. Disorders of the ANS can affect any system of the body They can originate in the peripheral or central nervous system and may be primary or secondary to other disorders. Symptoms suggesting autonomic dysfunction include orthostatic hypotension, heat intolerance, nausea, constipation, urinary retention or incontinence, nocturia, impotence, and dry mucous membranes. If a patient has symptoms suggesting autonomic dysfunction, cardiovagal, adrenergic, and sudomotor tests are usually done to help determine severity and distribution of the dysfunction.