The bear hat is sign of caution. That and it gets chilly where I paint.
I quite often find, that when I am working on a project, I pour all of my focus and energy into what I am doing that I get lost trying to perfect it (or at the very least, not hate it with a fiery passion). I don't realize how exhausted I am until somebody talks to me. Then my brain needs to reboot itself to accommodate. I haven't yelled at anyone yet, but my temper does get incredibly short.