Re: Females handshaking with non mahram males
It is different.
Science: There is no nerves in the hair so any one can register it as a touch.
Islam: I think you are right it should be no different then shaking hand and should be avoided.
Culture: It means protection and care from person who put hand on head.
Like one time I visited my friend who had little daughter not even 5, she came to me and offered her hand to shake 
, I ignored and only put hand on her head for like 1/25 of sec.