What I have found is HEAT DOES NOTHING TO HELP. It seems the autonomic system has a mind of its own. I can be sitting in a warm room and there goes the color in my fingers. I can fetch something from the freezer and my fingers remain pink. Emotions seem to be the strongest of any stimuli. I have thought a drop in barometric pressure might set it off. All I know is that it can be quite painful. Figure that! Bonnie mills