The Nervous System

The nervous system is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body. It is essentially the body's electrical wiring.

Structurally, the nervous system has two components: the central nervous system and the peripheral nervous system. According to the National Institutes of Health, the central nervous system is made up of the brain, spinal cord and nerves. The peripheral nervous system consists of sensory neurons, ganglia (clusters of neurons) and nerves that connect to one another and to the central nervous system.

Functionally, the nervous system has two main subdivisions: the somatic or voluntary component, and the autonomic or involuntary component. The autonomic nervous system regulates certain body processes, such as blood pressure and the rate of breathing, which work without conscious effort. The somatic system consists of nerves that connect the brain and spinal cord with muscles and sensory receptors in the skin.

Nerves are cylindrical bundles of fibers that start at the brain and central cord and branch out to every other part of the body, according to the University of Michigan Medical School.

Neurons send signals to other cells through thin fibers called axons, which cause chemicals known as neurotransmitters to be released at junctions called synapses. A synapse gives a command to the cell and the entire communication process typically takes only a fraction of a millisecond.

Sensory neurons react to physical stimuli such as light, sound and touch and send feedback to the central nervous system about the body's surrounding environment. Motor neurons, located in the central nervous system or in peripheral ganglia, transmit signals to activate the muscles or glands.

Glial cells, derived from the Greek word for "glue," are specialized cells that support, protect or nourish nerve cells.

There are a number of tests and procedures to diagnose conditions involving the nervous system. In addition to the traditional X-ray, a specialized X-ray called a fluoroscopy examines the body in motion, such as blood flowing through arteries.

Other standard neurological exams include an MRI (magnetic resonance imaging), CT scan, and an electroencephalogram (EEG), which records the brain's continuous electrical activity. Positron emission tomography (PET) is a procedure that measures cell or tissue metabolism and brain activity to detect tumors or diseased tissue or tumors.

A spinal tap places a needle into the spinal canal to drain a small amount of cerebral spinal fluid that is tested for infection or other abnormalities.

Treatments of nerve pain vary from antiinflammatory and pain medications such as opiates, to implanted nerve stimulators and wearable devices. Many nerve-pain sufferers also turn to herbal and holistic methods, such as acupuncture and meditation, to reduce their discomfort.

The branch of medicine that studies and treats the nervous system is called neurology, and doctors who practice in this field of medicine are called neurologists. Once they have completed medical training, neurologists complete additional training for their specialty and are certified by a professional board like the American Board of Psychiatry and Neurology. The doctors that perform surgeries involving the nervous system are called neurosurgeons.

There are also physiatrists, who are physicians who work to rehabilitate patients who have experienced disease or injury to their nervous system that impact their ability to function.

and are certified by the American Association of Neurological Surgeons.