@adamek3638 Thanks for your input Kathy. I agree that SFN controls sensory transmissions and I think is the sole cause for my temperature sensitivity. It has always seemed that autonomic is it's own very different animal. I'm trying to connect with other SFN folks that may share these symptoms but, we are all so different. When I was B12 deficient I had racing heart, rapid breathing and felt close to passing out. Since regulating B12, I do not feel that way. Found this chart to refresh myself and others who may find it useful. Enjoy your day!