This is a fancy way of saying “twitching eyelid.” Fasciculations are quite common, with people complaining that their whole eye has been twitching and jumping. Upon further discussion, we discover that it is actually their eyelid that has been twitching … they can both feel it, and often see the skin movement when looking in the mirror. These fasciculations are strange, but almost always harmless and usually caused by minor irritation to the eye. I like to compare eyelid twitching to hiccups. Hiccups usually start when water goes down the “wrong pipe.” This creates a sensation that the body needs to cough or retch … and yet, this body reaction is “overkill.” Instead, a funny feedback loop forms between the throat and diaphragm and results in rhythmic hiccups. A similar process may occur with the eye. The ocular surface may be slightly irritated and the eye “thinks” it needs to blink. However, the irritation isn’t really that bad, so the eyelid ends up twitching instead. The “eye hiccup” theory is my own, and while not entirely accurate, sums up the underlying process for most people. Most people get their lid twitching in waves, with them occurring off and on for several weeks then nothing for months. Certain stressors like caffeine, weather changes, and diet may set them off. If they are bothersome, I tell my patients to use artificial tears and antihistamine allergy drops. If the twitching involves the rest of the face and mouth (hemifacial spasm), occurs in both eyes at the same time (blepharospasm), or the vision itself “shakes” during the episodes (superior oblique myokymia) … this is more concerning and you need to be evaluated with an eye exam and possibly a neurologic consult.