How to mount tv on wall WITHOUT STUDS??

I'm trying to mount my 25 lb LCD to a wall above my fireplace. I've looked behind the wall (via a small panel on the side) and can see NO WALL STUDS. I have interlocking wood paneling - approx. 1/2-3/4" thick I would guess. Can I mount (the tv mount) directly to the wall without the studs?