1 Touch Response: The keys on a digital piano or keyboard can be weighted (similar to those of a traditional piano), touch sensitive (unweighted but still sound loud when struck hard), or neither.
In very rare instances, eyelid twitching can indicate a more serious condition, like the beginning stages of multiple sclerosis or a lesion on the brain stem. Those conditions typically begin with a host of symptoms, and in this circumstance the eyelid twitch soon moves to the facial muscles, as well.
Eyelid twitch may occur with other eye symptoms, such as watery eyes and irritated or red eyes or eyelids. Sometimes eyelid twitch appears along with facial tics, which are other involuntary movements of the face including grimacing and nose twitching.he most common known causes of eye twitch include fatigue, stress, anxiety, and excessive caffeine intake. Eyelid twitch may appear in response to irritation caused by smoke, dust, or a foreign body in the eye.