Amyotrophic Lateral Sclerosis
Author: mzPOTTER
What is ALS?
Amyotrophic lateral sclerosis (ALS), sometimes called Lou Gehrig’s disease is a progressive neurological disease, invariably fatal, that attacks the nerve cells (neurons) responsible for controlling voluntary muscles. This disease belongs to a group of conditions called motor neuron diseases, which are characterized by the gradual degeneration and death of motor neurons.
Motor neurons are nerve cells located in the brain, brainstem, and spinal cord that serve as control units and vital communication links between the nervous system and voluntary muscles of the body.
Messages from motor neurons in the brain (called upper motor neurons) are transmitted to motor neurons in the spinal cord (called lower motor neurons) and from there to each particular muscle. In ALS, motor neurons both upper and lower degenerate or die, and stop sending messages to muscles. Unable to function, the muscles gradually weaken and wear out (atrophy) and contract (fasciculations). Eventually, the brain loses the ability to initiate and control voluntary movement.
ALS causes weakness with a wide range of disabilities. Eventually, all muscles are affected under voluntary control and patients lose their strength and ability to move his arms, legs and body. When they fail muscles of the diaphragm and chest wall, patients lose the ability to breathe without a ventilator or respirator. Most people with ALS die from respiratory failure, usually within 3 to 5 years from onset of symptoms. However, about 10 percent of ALS patients survive 10 years or more.
Because ALS affects only motor neurons, the disease impairs the mind, personality, intelligence or memory of the person. Nor does it affect the senses of sight, smell, taste, hearing or touch. Patients usually maintain control of eye muscles and bladder function and bowel.