I'm building a site and one page contains a map of the county discussed on the site. When I move the mouse over different towns on the map, I need the map graphic to change. You can see the page I'm working on here:

http://staging.amadorcountyhistoricalsociety.org/concrete5.4.0.5/in...

I've tried adding JavaScript to the header.php file and adding the appropriate pointers in the HTML file, but that hasn't worked. I may be looking at this problem too much and I may have overlooked the solution in the forums, and so I'm hoping to either be steered to the correct discussion or get a response here as soon as possible. Thanks in advance for your help.