Definition

Lou Gehrig's disease, or amyotrophic lateral sclerosis (ALS), is a neurodegenerative disease of unknown cause that breaks down tissues in the nervous system and affects the nerves responsible for movement. Its common name comes from the professional baseball player whose career was ended because of it.

Description

Lou Gehrig's disease is a disease of the motor neurons, those nerve cells reaching from the brain to the spinal cord (upper motor neurons) and the spinal cord to the peripheral nerves (lower motor neurons) that control muscle movement. In Lou Gehrig's disease, for unknown reasons, these neurons die, leading to a progressive loss of the ability to move virtually any of the muscles in the body. The disease affects "voluntary" muscles, those controlled by conscious thought, such as the arm, leg, and trunk muscles. Lou Gehrig's disease, in and of itself, does not affect sensation, thought...