Which activities of the body are controlled by the autonomic nervous system?
Your autonomic nervous system (ANS) is the part of your central nervous system (CNS) that controls unconscious activities like breathing and digestion. This system is always working, whether or not you’re awake. You need this system to live. Show
What Is the Autonomic Nervous System?Your central nervous system has a central subsystem that consists of your brain and spinal cord. All other portions of your CNS are part of your peripheral subsystem. The peripheral subsystem is divided into two more parts of your nervous system — your somatic and autonomic nervous systems. Both your somatic and autonomic systems are spread throughout most of your body. Your somatic system is associated with your conscious thought. It allows you to control your muscle movements and gathers information from your senses. Your autonomic nervous system manages everything that occurs in your body automatically. You never have to think about it in order for it to work. It’s made up of three main parts, called the sympathetic, parasympathetic, and enteric or gastroenteric nervous systems. Interesting facts about the autonomic nervous system:
What Is the Autonomic Nervous System Made Of?For the most part, your autonomic nervous system is made up of neurons and a few other cell types. Neurons are the physical connections that stretch from your brain and spinal cord to almost all other areas in your body. They transmit information using both electrical and chemical signals. What Does the Autonomic Nervous System Do?The autonomic nervous system functions throughout your body. It can receive stimulation from your environment through your senses. Impulses can also start in your brain. In your brain, your limbic system exerts a lot of control over your ANS via your hypothalamus. Your limbic system is associated with memory and emotions, like fear. This means that your state of mind can indirectly impact your ANS. The main function of your ANS is to control your subconscious bodily processes. It maintains homeostasis throughout your body. Homeostasis is the state where all of your bodily functions are well-balanced and stable. Each part of your ANS has unique functions. The sympathetic and parasympathetic systems work in harmony to maintain your overall homeostasis. In general, the sympathetic system speeds up or energizes processes, and your parasympathetic system calms them back down. Sympathetic nervous system. This system manages your fight-or-flight response. It triggers this response throughout your body by using the neurotransmitter epinephrine. The fight-or-flight response evolved for use in life-threatening situations. However, it can also be triggered by anxiety and everyday stresses. Specific functions of your sympathetic nervous system include:
Parasympathetic nervous system. This system controls much of your body when you’re at rest. It’s in charge of promoting quieter activities and returning your body to normal after a stressful event. Functions of your parasympathetic system include:
Enteric nervous system. The main function of this system is to digest food and absorb nutrients. It controls your digestive muscles and causes them to contract and relax. It also helps direct your blood flow. Where Is the Autonomic Nervous System Located?Parts of your autonomic nervous system are located throughout your body. It incorporates neuronal fibers in four of your twelve cranial nerves. These start in your brain. Other parts of your ANS depend on nerves that start in your spinal cord. For the most part, your parasympathetic system uses more of your cranial nerves, and your sympathetic system relies more on the nerves that stem from your spinal cord. Your sympathetic nervous system has nerve fibers in nearly every tissue and organ in your body. For example, it has nerves in your: 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. Your enteric nervous system extends throughout your digestive tract, which runs from your mouth to your anus. It is the largest of the three parts of your ANS. Not everyone experiences the same symptoms when they have a problem with their autonomic nervous system. Since the ANS is spread throughout your entire body, symptoms can affect many different body parts simultaneously. Different conditions can damage your ANS in unique ways. Signs of dysfunction with your ANS can include: Any kind of significant damage to your autonomic nervous system is called autonomic neuropathy. In a large number of countries, the main cause of this damage is untreated type II diabetes. The exact way that this affects you can vary from person to person. For example, it could affect the way that your blood pressure changes when you stand. Other examples of autonomic nervous system conditions include:
Some conditions can specifically affect your enteric system. Most of these are already present in early childhood. Damage to your autonomic nervous system can be very harmful to your overall health. The best way to prevent diseases that can damage your ANS is with healthy lifestyle choices like: SOURCES: Cleveland Clinic: “Autonomic Nervous System,” “Guillain-Barré Syndrome.” Simply Psychology: “Autonomic Nervous System.” Waxenbaum, J.A., Reddy, B. Varacallo, M., StatPearls, “Anatomy, Autonomic Nervous System,” StatPearls Publishing, 2021. |