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.
Eye Twitching, also known as blepharospasm or myokymia, is a sudden, involuntary movement of the eyelid; it is also referred to as an eye muscle spasm. These spasms often occur in stressful situations or when the affected individual has gone too long without sufficient rest.ther common eye twitch causes include: 1  Stress. 2  Irritation of the Cornea or Conjunctiva. 3  Fatigue/Lack of sleep. 4  Prolonged staring at a computer screen or television. 5  Excessive caffeine intake (e.g., coffee, tea, caffeinated sodas). 6  Nervous system disorders.