I also have sworn that I have felt twitches in my arms that I couldn't see..... while I was feeling it. In one months time, I think I have had every kind of twitch that you can have. I have had some I can see but can't feel, some I can feel but can't see, some that feel like buzzing (fingers and toes), some that thump to the point of being visible through two layers of clothing (usually shoulders), and some that look like little dimples or worms under the skin (calves). I've had fast "automatic machine gun" twitches, slow twitches, single twitches (or popping sensations) all over the body, and some I probably haven't even thought of. Every couple weeks I seem to discover a new type of twitch in a new location, some that I didn't even think I had muscles to twitch. I twitched on my chin today, and have had a running hotspot in my left ass cheek. I've also had cramped calves, cramped feed, feelings of weakness on my left ankle, left leg, and left arm (left is my twitching side). I am finally getting to the point that I may really not have ALS and might in fact be a BFS'er. Part of what has convinced me of this is having no weakness, and every type of twitch under the sun. Here is my advice from experience:1. Try not to worry every time you get a new type of twitch (like feel but no see). If you do, BFS will drive you wild. 2. A doctor, I think Twitchydoc, has actually discussed Fibrillations on this site in another post. He said that you absolutely will NOT feel OR see fibrillations. Theses are twitches of single muscle fibers that are much to small to see or feel, and can only be picked up on an EMG. Single muscle fibers are way too small for you to perceive, so don't worry about fibrillations unless they show up on an EMG. 3. There seems to be no consensus (including amongst the experts) what ALS or BFS twitches look like. Some think ALS twitches start out focal and BFS start out diffuse; and yet I've seen atleast one professional say the opposite of each. Some say ALS twitches are hard to notice, others report noticeable twitching in ALS. The only thing that everybody seems to more or less agree on is that twitching without weakness, especially in the under 40 crowd, is NOT a sign of ALS, and if it is an initial presentation it's a RARE presentation of a RARE disease. My personal theory is that everybody has their own unique twitching whether they have BFS or ALS, and the only real difference maker is that those with ALS have other symptoms (and more importantly signs a doc looks for like abnormal reflexes). If it makes you feel better, I've actually read a paper on ALS diagnosis that suggested that patients under the age of 40 that come in for twitching and have a clean neuro exam don't even require an EMG (the only thing I"ve personally had is neuro exam and bloodwork from GP). Even over 40 is probably still benign, but the the chances of ALS go up slightly and the chances of BFS go down slightly with age. It seems that many on this site report experts that give them EMGs for the sake of reassurance alone. 4. Stay the hell off of google. Seriously. I did not start making progress in beating this anxiety until I stopped googling. You will find a bunch of reassuring facts (like statistics) that you will ignore and the occasional odd ALS testimony that you will latch onto and will scare the hell out of you. Google is psychological poison for those of us who suffer from health anxiety.