I was observing the GrizzCub the other night. He wanted to stay awake and was fighting off sleep.
I noticed that he kept rubbing his eyes and rubbing/scratching his head. I know that when I’m tired that I tend to run my fingers through my hair, scratching my scalp as I do so.
Is this a semi-involuntary reaction to help us stay awake? I would think that something likening to a scalp-massage would be more apt to help someone fall asleep.
perhaps the rubbing/scratching helps to increase blood flow?
One thing I notice about myself is that when I get sleepy, my eyes get dry. Possibly this is a side effect of my fighting to keep them open, and thus somewhat upsetting the normal blinking frequency. (Hey, I just used the word blinking and it wasn’t a euphemism.) Anyway, as the good folks at Visine have been telling us for years, dry eyes are itchy eyes.
As to the head scratching, well … that’s a head-scratcher. 
For that matter, why do we scratch our backs first thing in the morning when we’re standing in the bathroom and contemplating the day ahead.
Or is it just me? It is? OK forget I said anything. 
i like to scratch all over. all, um… over. cough.
good question, **GrizzRich
**.
jb
Why do we rub our bellies and pat our heads when we’re tired? What?
(We really need a “looking around, ‘did I just say that’” smiley.)
might Unca Cecil be interested in this one? hmmmmm…?