Sensory nerves and the autonomic nervous system, which controls functions like sweating, generally remain functional.
Amyotrophic lateral sclerosis is a advanced, usually fatal disease. It is caused by the erosion of motor neurons, the nerve cells in the central nervous system that control voluntary muscle movement. This disorder is one of the most common neuromuscular diseases worldwide, and people of all races and ethnic backgrounds are affected. Although many authors consider amyotrophic lateral sclerosis to be caused by a combination of genetic and environmental risk factors, so far the latter have not been firmly identified, other than a higher risk with increasing age. The progressive degeneration of the motor neurons in ALS eventually lead to their death. When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, patients in the later stages of the disease may become totally paralyzed.