As a parent, I would completely ignore it for right now. It could be an emotional thing right now or for attention. If there are other siblings, is any one getting more attention than the other. Is he being rushed through activities or is he being told to do this or do that over and over. Also, kids will do this when parents yell at them or scold them and most parents don't even realize what they are doing. He is probably a real sensitive child and you may have to take a little more time with him and give him lots of hugs and kisses and tell him each time he does something good, praise him for it. I know kids who get tics from this situation - even teenagers - and usually disappears when you are not even noticing. Try this first for at least a month and if you are at your wits end. Seek professional help. I know parents who tell their kids teasingly things that are devasting to the child and the parents laugh not knowing how much they have hurt that child. It really is going to take some special time with him and you have to do it evey day. It will probably wear you out, but it is worth it. Good luck.