Amyotrophic Lateral Sclerosis
Alternate Names : Lou Gehrig Disease, Progressive Bulbar Palsy, ALS
Amyotrophic lateral sclerosis, also known as ALS, is a progressive disease
of the nervous system. Nerve cells, called neurons, are located in the spinal cord and
brain and normally give signals to muscles. ALS causes these neurons to degenerate,
or break down. So, when neurons stop sending signals to muscles, the
muscles atrophy, which means they weaken and shrink. This may progress to paralysis. Spasticity is
increased muscle tone that can make it hard to coordinate movement, and it may also
develop as a result of ALS.
What is going on in the body?
The muscle weakness in ALS can affect the muscles of the limbs or of the
tongue, mouth, and throat. The nerves that connect the brain and spinal cord, called
motor neurons, can also degenerate.
What are the causes and risks of the disease?
Cases that run in families are often due to a defect on one of the
chromosomes, the structures that hold genetic information. Otherwise, the cause of
ALS is not known.