Best Way to Exfoliate Scalp

I am looking for a brush specifically designed to exfoliate the scalp. I don't really have a build up problem but have noticed that if I take a hard plastic comb and run it in circles lightly on my scalp to remove the layer of dead skin it looks much healthier and appears to have a positive effect on hair growth. Is there a brush specifically designed to to this? I have heard about using a "Shampoo Brush" to do this but am curious if there are other items made specific for this purpose.