Hair and Japanese Films

I don't know if this is a recent thing or not - but watching some trailers for Asian films on Tartan DVD the other night, I noticed a lot of horror films where female black hair (usually wet) is being used to create an aura of terror. I'm obviously thinking of the Ring cycle in particular, but also of The Grudge and others as well...
I'm well aware of some of the symbolism of male hair representation (power and sexual potency) in literature (and you only have to think of werewolf films to think of some male hairiness examples - Ginger Snaps didn't cut it in my book, and was of course more about blood than hairiness) with Samson shorn and the Father in Balzac's Cousine Bette suffering a hyperinflation of hairiness and sexiness (as the rest of the family goes down the tubes). This seems somehow different.
I know blonde hair has a strong connotations (and I seem to remember reading a review in Le Figaro a few weeks ago about a Cambridge Professor's book about blondes - apparently female blonde hair is strongly associated with saintliness in parts of Africa, and certainly Virgin Mary representations play a strong role in this). Rapunzel lets down her hair (blonde in all the books I remember), Rumpelstitskin weaves the blonde hair into golden threads...but I don't remember much in the realm of black hair (which will obviously play a more central role in Asian symbolism) - even red hair I can think of more symbolc links (although these are generally evil, being connected with the Devil and vampires).
Anyway, I'd love to know if anyone knows much about the symbolism of long, straight, dark hair in Asian cinema (or literature and art), and why it appears to be linked to female ghosts, I'd love to know.