Thanks for your question and I recommend that you speak with your doctor
about your concern. First, there is more information that can help with this question: are you otherwise healthy? Have you had any problems with any other nerves or similar sensations in the past? Are you taking any medications, especially psychiatric medications or medications that can affect the nerves? If the answer to all of these is no, then other questions such as whether or not the intensity or frequency of these twitches is happening come up as well. If all of these symptoms are stable and there is no real change over the years, it could be possible that this is a simple twitch similar to what most people will have for one reason or another, and it could be that it will be difficult to definitively determine what is causing this symptom. Usually these will have to do with a reflex arc between the muscle and the nerve, but this is only one possible explanation. If you feel that your symptoms are changing with time, becoming worse, or more persistent, then it may be that this is something more serious that needs more urgent intervention. Your doctor will know how to appropriately guide you next. Please speak with your doctor.