In the name of Allah the most Beneficent and Merciful
The wiping over the hair of the head for men and women are the same for Wudhu. The method is wiping over the head and hence when they bring the hands back they should do it lightly so that the hair becomes wet. It is not necessary for the scalp to become wet.
Of course Allah knows best
[Answer provided by: Muhammad Salim Ghisa]