Your parasympathetic nervous system is the smallest of the three autonomic nervous systems. For the most part, it only has nerves in your head and external genitalia.

This article – the sixth in a series about the nervous system – discusses the function of the autonomic nervous system, which is a component of the peripheral nervous system. It regulates involuntary ...

Your autonomic nervous system controls things that your body does without having to think about it, such as breathing and digesting. Autonomic dysreflexia (sometimes also called hyperreflexia) is ...

Central nervous system — the brain and spinal cord; Peripheral nervous system — the nerves that make your muscles move and tell your brain what your body is feeling; Autonomic nervous system — the ...

The autonomic nervous system is a complex network of cells that controls the body’s internal state. It regulates and supports many different processes, often outside of a person’s conscious ...

The sympathetic nervous system becomes overactive in a number of diseases, according to a review in the journal Autonomic Neuroscience. These include cardiovascular diseases like ischemic heart ...

Reproductive system: It increases blood flow to the penis to initiate an erection. ... The autonomic nervous system comprises two subdivisions: The sympathetic and parasympathetic nervous systems.

Ultimately, the primary function of the sympathetic nervous system is to help the body maintain balance and stay alert by continuously regulating heart rate, blood pressure, breathing, oxygen flow ...