Why does my cat like to chew my hair and scalp?

I have a cat that for many years has liked to bury her nose in my scalp (right around the part) and then chew (like rub her teeth on the hair) and sometimes take her claws and “attack” my head. If I’m sitting on the couch, or the deck, or in bed with my head low, she will come up behind my head and start rubbing her head in my hair and then do this strange behavior.

Does anybody else have a cat that does this strange thing? Do you have any idea why a cat would do this? My hair is clean – washed daily so it’s not like it’s smelly or dirty.