Medically reviewed by Katrina Carter, DPT Key Takeaways Voluntary muscles can be controlled by the person, like muscles in your neck and legs. Involuntary muscles work without you thinking about it, ...

The muscle twitch creates short, involuntary muscle contractions, which affect tiny muscle areas that lie beneath the skin.

Chorea-acanthocytosis is a rare genetic disorder of the nervous system. It causes involuntary jerks and twitches in the muscles, known as chorea, and star-shaped red blood cells, known as ...