Wrongo: they give *off* the most heat, and therefore will show up 'hot' on infrared. Things that are well insulated show as being cool. The head is the least insulated part of our body actually (and shows the hottest in most cases) with the exception of when you have very long and thick hair, which (and you guessed it) works as an insulator for your head and blocks the heat signature.



The more you know! =D