nervous system of humans and animals is divided into two types - a somatic and autonomic nervous system.Somatic nervous system is under the control of the conscious person and can obey him, and the autonomic nervous system, by contrast, is not subject to man, and is under the control of his unconscious.
Somatic system performs a dual function.It receives information about the environment through the senses - like eyes that have special receptors.Signals from these receptors fall on sensitive channels in the central nervous system.Also somatic system gives signals from the central nervous system for motor channels to the skeletal muscles, causing this movement.
autonomic nervous system - a department of the nervous system that regulates vascular tone, lymphatic and blood vessels, the work of exocrine glands and internal secretion, as well as all internal organs.
VNS holding down the constancy of the environment (homeostasis) in the body and performs the adaptive-trophic function.Due to the autonomic nervous system function of internal organs and the whole human body to adapt to changes in the external environment and its impact on mental and physical activity.
autonomic nervous system (stand-alone) is divided into two sections: peripheral and central.In the peripheral part consists of nerves, nerve fibers and branches that come out of the centers of the system in the brain and spinal cord, plexus of nerve fibers and nerve ganglia (vegetative nodes), the sympathetic trunk, which consist of ganglia with connecting nerves and branches, as well asvegetative nodes parasympathetic division of the ANS.
Central Division VNS is divided into segmental (lower) and suprasegmental (higher) autonomic centers.Segmental centers are located in the spinal cord and in the brain.Suprasegmental ANS centers focus only in the cerebral cortex, mainly in the parietal and frontal lobe, the olfactory brain, the cerebellum, hypothalamus, subcortical structures, and so forth.
The autonomic nervous system has two types - the parasympathetic and sympathetic.They differ in the arrangement of their effector and central neurons and reflex arcs, as well as their influence on the work of the innervated structures.
The parasympathetic parts of the nervous system are the central neurons in the spinal cord in its sacral segments (segments 2-4), but the majority of these neurons located in the brain stem and leaves him with mixed cranial nerves.The sympathetic nervous system, the central neurons in the spinal cord are located in the gray matter of the cervical segment of the eighth to two or three lumbar.Sympathetic nerves depart only from the spinal cord on the ventral (front) spines in the composition of the spinal nerves.Through parasympathetic nerves serving the work of the bronchi, they are narrowed, the sympathetic nerves, on the contrary, expand the bronchi.
The autonomic nervous system is responsible for all vital functions and processes in the body, as well as partly responsible for the reproduction, which is very important in procreation.VNS also provides normal regulation of heart rate, body temperature, blood pressure, monitors the activity of different biochemical processes in the body.At the slightest changes in internal or external conditions, autonomic system triggers compensatory and monitoring mechanisms at the right time, change the tone of blood vessels, control breathing and stimulates mental activity.
