I've had this very weird symptom on and off throughout my CFIDS "career." I have a killer headache (that's not the weird part; I have killer headaches every day of my life), and sometimes it is accompanied by what feels like chills between my brain and my skull. It is an odd feeling, sort of like having a zillion gnats crawling on my skull. Has anyone else expereineced this? Has anyone figured out what to DO about it? Nothing I have tried makes any difference. I can't even get rid of the headache!!