Caption Style in Document Map

I am using Word 2002 and, with long documents, find the Document Map useful
as a way to navigate between chapters. However, a file that I am editing
has placed lines with the "Caption" style in the document map, which now
appears at the same level as Heading 1. This has junked up the document map
to the point where it is unuseable.

The same thing happens when I switch to Outline view and click "Show Level
1" - the Caption Styles appear as well as the Heading 1's.

Any suggestions? Thanks in advance!