Timed Image Rotation

Hi, I am trying to setup a timed image rotation. Currently I have a 3 icon spots that when rolled over display a different image (1 of 3 images) in the background depending on which icon is rolled over. What I am trying to do is if neither of the 3 icon spots have been touched for 10 seconds the background image automatically changes to the next image. I’m trying to learn how to use getTimer and setInterval but can not seem to figure this out. If anyone could help me out I would really appreciate it.

Thanks,
Brian