There are ALWAYS such segments. That's the tough part, the part which separates the men from the boys.
Yes, there are, but they never had MTV before....One of the popular techniques I have noticed involves either flashing images (which can be easily used for subliminal 'messages' whether they are spelled out or merely conveyed via images).
Another is jigging the camera around when they really don't have anything to show you that would hold interest in a steady shot--just to make something appear to be significant--while obscuring what you are looking at. That can work with subliminals, too.
Freeze frames may reveal background elements which spin the images differently, but you see them anyway, whether you realize it or not.
I don't watch those sort of spastic images any more, and never did much (A Clockwork Orange, the reprogramming sequence comes to mind). (FWIW, I always thought MTV (and the music video) was a personal waste of time as well.)
And I really like parental lockouts on TV sets/cable, at least I can leave the kids in the room.