In 1980 Alberca et al. described a patient with a syndrome of increased muscle irritability, who presented ondulating muscle rolling movements and electrically silent cramps, myoedema and muscle reactions to mechanical stimulation similar to myotonic response, suggesting a disfunction at myofibrillar level.
For c-3po, it was a costume, Anthony Daniels played c-3po: For R2-D2, It was a costume and a remote controlled robot. CGI was also used in the prequel trilogy. So, they had Kenny Baker to play him : And from Portrayal section of wookieepedia article on R2-D2 :
will friedle who played terry mcginnis the second batman in batman beyond plays the villain gearhead adam west who played batman in the campy 1960s batman series and the gray ghost in batman the animated series plays gotham s mayor marion grangeron perlman who played clayface in batman the animated series played both killer croc and rumorfrank gorshin who played the riddler in the campy 1960s batman series played dr hugo strange until his deathon perlman who played clayface in batman the animated series played both killer croc and rumor frank gorshin who played the riddler in the campy 1960s batman series played dr hugo strange until his death