 | This article needs more reliable medical references for verification or relies too heavily on primary sources. (July 2020) |  |
| Fasciculation | |
|---|---|
| Other names | Muscle twitch |
 | |
| Animated image showing involuntary twitching in the upper eyelid of a young adult male | |
| Pronunciation | |
| Specialty | Neurology |
A fasciculation, or muscle twitch, is a spontaneous, involuntary muscle contraction and relaxation, involving fine muscle fibers.[1] They are common, with as many as 70% of people experiencing them.[1] They can be benign, or associated with more serious conditions.[1] When no cause or pathology is identified, they are diagnosed as benign fasciculation syndrome.[1]