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.
It's not known exactly what causes the twitches, but they appear to be associated (although by no means invariably) with (a) anxiety and (b) some faint stimulus, such as a noise. The twitches have been induced in test subjects who were instructed to push a button whenever they heard a low tone. When, as usually happened, the subjects nodded off after a while â you know how exciting psychology experiments are â the tone would often cause a subject to twitch after a lag of a few seconds.