Sistema nervioso AUTÓNOMO [Simpático y Parasimpático]
Understanding the Autonomic Nervous System
Overview of the Autonomic Nervous System
- The autonomic nervous system, also known as the vegetative nervous system, regulates internal activities such as blood pressure, digestion, sweating, urine formation, and body temperature.
- It operates without voluntary control or conscious awareness and coordinates with centers in the brain and spinal cord to direct responses to muscles and glands.
Divisions of the Autonomic Nervous System
- The autonomic nervous system is divided into two main branches: sympathetic and parasympathetic. These divisions differ in anatomy, function, and chemical transmitters involved.
- Norepinephrine serves as the primary neurotransmitter for the sympathetic division, while acetylcholine is predominant in the parasympathetic division.
Functional Differences Between Sympathetic and Parasympathetic Systems
- The sympathetic division prepares the body for action during stress (fight or flight response), increasing heart rate, blood flow to muscles, and energy expenditure. This includes physical reactions like increased heart rate due to heightened neuron discharge from this system.
- In contrast, the parasympathetic division promotes restorative activities by slowing down bodily functions post-stress; it decreases metabolic rate and enhances digestion after meals or during relaxation periods.
Interaction Between Sympathetic and Parasympathetic Systems
- Many organs receive innervation from both systems which generally have opposing effects; however, they can collaborate in certain responses like salivation and male sexual response.
- A third division called enteric is noted for its extensive network within digestive walls that regulates secretion and absorption processes while being modulated by other autonomic divisions. This ensures proper digestive functioning.
This structured overview provides a comprehensive understanding of how the autonomic nervous system operates through its various components while highlighting key differences between its divisions along with their collaborative roles in bodily functions.