I agree with the other poster, stuttering + anxiety. It's my assumption that when you talk you build up anxiety until you reach your maximum, and at that point talking becomes extremely difficult. Taking a breather lets you relax, the anxiety goes away a bit, and you can talk again for a while. Things to try that helped me.. Fidget, such as tapping your foot while you're talking, or tapping your thigh with your finger. You could also try buying a fidget device (look them up). Purposely talk slower and change the tone level of your voice a notch or two, either up or down. Try meditation, yoga, and change your lifestyle to get yourself out of anxiety inducing environments. Or, you can use the philosophy of "I don't get a sh\*t!" like I do, but I only do that in a surgical manner. Only on things that anxiety would be its worst, but then again I still am professional, such as at the workplace. It just calms me down a bit, as strange as it sounds. I know ultimately I do give a sh\*t, but it gives me some peace lol.