Sliders

Hello...So I'm trying to create a slider that will move some tiles left to right. I also want the illusion they are moving left to right and visa versa.

I have figured out motion paths for the initial left to right motion, but does anyone now how I can revers the action when someone slides the slider back down again, or if it can even be done?

Imagine video tiles on a website that move left to right and back again when you click the < > on screen...that's the effect I'm after and thought a slider work well.

Any help would be appreciated or suggestions.