While their size and shape vary with location in the nervous system, most neurones contain the same parts: a cell body; a number of highly-branched outgrowths of the cell body called dendrites; a single, long nerve fibre (or axon) extending from the cell body; and branches at the end of the nerve fibre (axon terminals).
My doctor said that usually happens when blood pressure is high and you get that strange head sensation. But as I was reading some documents on net, I found out that it could also be some sort of a panic attack. You could try next time it happens to relax, try thinking on some peaceful place, and just calm down.
Sensation: that sensation you are having sounds like neuropathy. A nerve is irritated in your scalp. Look for a rash in the area, it may be shingles. Many neuropathies resolve ( like when you hit your funny bone), if it persists for over a day, see your doctor.