Spinal nerves could be described as the interstate highway system of the human body. It is these nerves that transmit thoughts and other impulses from the brain to other parts of the body, enabling humans to move, walk, run and physically participate in the world around them. They are also responsible for the functioning of the body and allow humans to sense things and react to what they feel.
The spinal nerves are an important component of the peripheral nervous system (PNS), which works in conjunction with the central nervous system (CNS) in the transmission of motor, sensory and autonomic impulses. Comprised of the brain and the spinal cord, the CNS extends to the lumbar vertebra, which is in the lower section of the back. The PNS branches out from the entire length of the spinal cord to the extremities and to the organs of the body.
The spinal cord has literally thousands of nerve fibers that are constantly sending information through chemical and electrical processes to and from the brain. Spinal nerves serve as conduits of that information. The two systems work together using what are known as receptors and effectors.
There are actually 31 pairs of spinal nerves whose roots pass through what are known as intervertebral foramina, which are essentially openings in the vertebrae. Twelve of these are thoracic spinal nerves, which are responsible for the movement of the body in the areas of the chest and abdomen, and of the fingers of each hand. Eight cervical nerves located in the neck make possible movement in the arms and upper trunk area, including the neck, and also regulate the breathing process. There are also five lumbar and five sacral nerves in the lower back that exert control over bowel and bladder functioning, as well as the sex organs. The coccygeal nerve is the final part of this nextwork, and extends into the tail bone.
Different parts of each spinal nerve have different functions. The front part, or anterior, carries impulses from the brain that in turn control motor reactions, allowing muscles to move. The rear or dorsal section carries to the brain information that has been obtained from various organs, including hot or cold temperatures felt by the hands or the texture of the ground felt by the feet. Spinal nerves also have an important autonomic function through their regulation of internal organs, including the beating of the heart. The autonomic nervous system in which spinal nerves have an important role is itself divided into the sympathetic and the parasympathetic aspects, which, alternatively, exert control over certain involuntary actions of the body in times of stress and while it is at rest.
Spinal nerves and their related elements are subject to a number of disorders that can be both painful and debilitating. The website SpineUniverse lists a host of such disorders, the most notable of which is peripheral neuropathy, which can be brought about by age, environmental elements and nutritional deficiencies.
Damage to spinal nerves can result in the paralysis of them and of the muscles they may serve, while a dysfunctional autonomic system can be life-threatening. The importance of spinal nerves is reflected by the consequences of their improper functioning.