Recent tests have shown this belief to be false, and that essentially all exposed body parts lose heat equally. Most likely, because our face and head are more sensitive to changes in temperature, it feels as if covering them up does more to prevent heat loss. In my experience, covering my head, neck and shoulders gives me the most comfort in cold environments. Similarly, I can’t help but think about how I place a newly created coal low in a tinder bundle so that it builds heat above it to assist in creating a flame. So, if heat travels upward, I’ll want to capture it. Failing this, I’ll fall back on the “mind over matter” rule… if you don’t mind, it doesn’t matter.