--one of the most common associations of Sjogren's syndrome is ganglionitis or neuronopathy:

http://neuromuscular.wustl.edu/antib...n.html#sjogren

And yes, "the odd sensations"--parastheses, in medical terms--can range from those caused by actual muscle fasciulations to those that feel like muscles are in movement when they are in reality quiet (and this is even demonstrable on EMG testing); I know I get feelings of crawling, feelings of water slowly dripping (when nothing is there, of course), periodic pulses, electrial zings, tingles, a feeling of flushing or slowly spreading warmth . . .never mind the actual neural pain. I tend to agree with Mrs. D that a lot of these erroneous sensations come from compressive forces on nerve that cause signals that the brain has trouble interpreting.