Zbrush Alpha push and pull at same time?

Mypeople

I have several alphas created from crazy bump and when i drag out an alpha it only pushes, it would be GREAT if it pushed from the white areas from the alpha and the dark areas pushed down. i heard this can be done in zbrush, but i have no idea how to do it. any help would be really appreciated.

cryrid

Mine does that by default; what do your alphas look like and what brush are you using?