You may use a certificate of citizenship or a naturalization certificate, to prove that you are a US citizen. But both the documents are not the same. A US citizenship certificate is granted to a person who acquires or derives citizenship from his US citizen parents.
Causes Of Twitching Of Fingers And Thumb. 1  Carpel tunnel syndrome causes twitching of muscles as the median nerve through the carpel tunnel becomes compressed. 2  A less disconcerting cause is muscle cramps that happen when small muscles in the hand contract.
The most common cause of isolated finger twitching like this would be muscle strain or muscle fatigue. This commonly occurs in people who work a lot with their hands, for example those who type on a computer keyboard all day long.