Video: You’ve Heard of ALS. But What Is It?

Desi Kessler, above, was diagnosed with ALS at 28 after the birth of her daughter. [Credit: Sarah Parker]

(NEW YORK) — Most of us have heard of the disease ALS, but might not actually know what it is.

ALS (amyotrophic lateral sclerosis) is a progressive neurodegenerative disease that affects neurons in the brain and spinal cord, eventually leading to muscle wasting and the inability to move the body. 95% of cases appear with no known cause. This makes it particularly difficult for researchers to pin down treatments or find a cure.

Watch this explainer—created, edited, and produced by Sarah Parker—to gain a deeper understanding of how the disease manifests. Follow the personal story of ALS patient Desi Kessler, and get easy-to-understand information from neuroscience expert Dr. Shane A. Liddelow.