Library · Disease
Amyotrophic lateral sclerosis
Make it clearer
Amyotrophic lateral sclerosis, which many people know as ALS or as Lou Gehrig's disease, is a neurodegenerative disease: the neurons, the cells of the nervous system, are damaged and lost over time. It is progressive and paralyzing.
What is lost are the motor neurons, the ones that command movement. There are two segments: the upper motor neuron, which runs down from the brain, and the lower motor neuron, which heads out to the muscle. Amyotrophic lateral sclerosis affects both. The cable that carries the brain's command to the muscle fails.
Why it happens is not known. Several mechanisms have been proposed: genetic mutations, oxidative stress, excitotoxicity, which is an excess of stimulation that ends up damaging the neuron, and problems with axonal transport, the system the neuron uses to move materials along its longest projection. None has been confirmed as the cause.
Most often it starts with signs of lower motor neuron degeneration in an arm or a hand, though in other people it begins with bulbar symptoms, the ones that involve speech and swallowing.
In brief
Amyotrophic lateral sclerosis is a progressive, paralyzing neurodegenerative disease that affects upper and lower motor neurons.
The cable that carries the brain's command to the muscle fails.
Its cause is unknown; proposed mechanisms include genetic mutations, oxidative stress, excitotoxicity and impaired axonal transport.
It usually begins with signs of lower motor neuron degeneration in the upper limb, though it can also present with bulbar symptoms.
Sources (1)
- National Center for Biotechnology Information, StatPearls PublishingAmyotrophic Lateral Sclerosis, StatPearlsPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated