Dried out brain

A couple of months ago I had this horrendous migrane. I get them about every three months or so. So I was talking to a friend about the day I had leading up to getting the migraine - and she said she thought most headaches were caused by dehydration more than anything else. So I tell her about my day (coincidentally completely lacking in liquid), and she says, "Well you've gone and dried your brain out! That's why you've got a headache!"

Ever since then, the mental image of my brain, dried out and crusty looking, has stuck with me. Every time I have a headache, I think about that image. I think about my brain being as dry as the leaves in autumn. That image alone makes me run to drink loads of water....which most often than not, along with monster amounts of drugs, makes the headache go away. Isn't that weird, to think about one's own brain as being dried out? Even if it is, it seems t0 work as a way of getting rid of headaches.