hotkey specific layer

hey..

first of all i wanted to say hi to everyone since im new here. my question is this:
Is it possible to hotkey a specific layer's visibility (e.g. a diffrent layer than the one i am currently working on)? i know its possible to create a hotkey for the layer i am working on, but it would be helpful to hotkey a different layer. my usual setup when working on a painting from reference is to have the ref image as one layer, a "screen" layer, a pencil layer with rough sketch, than i add an underpainting layer, than a final layer. i also use an intous 4. sometimes when im working i get into a zone and try to hide a layer, whether it be my ref image, on my sketch layer, than continue painting. well, as i said, being in a "zone" i dont always notice that sometimes i actually select which ever layer i was trying to hide.

it ends up being a pain in the butt... so i was hoping there was someway to hotkey a specific layers vis.

if anyone has any suggestions, plz feel free to let me know