Edit contrast in a mask through adjustment layers?

[rikkarlo]

  Hi all,

I have this picture and I've applied the gray scale image as a mask. 
How can I edit the contrast or brightness of the mask directly in the mask without rasterizing it back to a layer?

[David in Яuislip]

If you add a curves layer to the mask, select the Alpha channel and adjust the curve you'll change the contrast of the mask

[rikkarlo]

I was missing to set the "alpha" channel in the live filter, thanks!