The Scroll Motion effect in Adobe Muse defines the motion of an item in relation to vertical scrolling in a web browser. As a page is being scrolled down by the user, you can define horizontal and/or vertical motion for an item.
This effect opens new design possibilities when designing a Web page. Let me show you how it works on this specifically designed website. There you'll get some insight as to how to create the scroll motion effect.
Remember that Adobe Muse is also part of a Creative Cloud membership.