The Autonomic Nervous System (ANS) is responsible for regulating involuntary bodily functions such as heart rate and breathing. The spelling of the word can be understood using the International Phonetic Alphabet (IPA). The first syllable, "au", is pronounced like "ah" as in "father". The second syllable, "to", is pronounced like "tah". The final syllable, "nom-ic", is pronounced like "naw-mik". The ANS is a crucial part of the human body, controlling many vital bodily functions that we don't consciously think about.
The autonomic nervous system (ANS) refers to the part of the peripheral nervous system that regulates involuntary bodily functions, maintaining essential bodily processes such as heart rate, digestion, respiratory rate, and blood pressure. It plays a crucial role in maintaining the body's homeostasis, ensuring the balance and stability of internal conditions.
The ANS is divided into two main branches: the sympathetic nervous system and the parasympathetic nervous system. The sympathetic nervous system is responsible for the body's fight-or-flight response, increasing heart rate, dilating pupils, and releasing stress hormones to prepare the body for emergencies. On the other hand, the parasympathetic nervous system elicits the rest-and-digest response, promoting relaxation, reducing heart rate, and enhancing digestion and nutrient absorption.
These two branches of the autonomic nervous system work in a coordinated manner, counterbalancing each other to maintain optimal bodily functions and respond to various internal and external stimuli. They regulate processes that are largely outside of conscious control, allowing individuals to respond to events without actively thinking about them.
Disruptions in the autonomic nervous system can lead to a range of medical conditions including hypertension, gastrointestinal disorders, cardiovascular diseases, and various forms of dysautonomia. Understanding the complexities of the autonomic nervous system functions can aid in diagnosing and treating these conditions, allowing for improved management and care.
Parasympathetic or craniosacral nervous system, that portion of the vegetative nervous system, the fibers of which are derived from the midbrain, medulla, and sacral cord; the sympathetic and autonomic systems are antagonistic, yet both furnish fibers to the heart, to the muscles of the genital organs, and to the organs having smooth muscles; the vagus is the most important nerve of the autonomic system. (See plate.) By some writers the terms sympathetic and autonomic are used synonymously.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.