How to add hover effect on the map area using javascript

[hyunmoo0310]

this is my html body:
<img src=“iFH Image Hosting” usemap="#image-map"width=“257” height=“450” class = “map”>

and i added html header in the workflow:

<script type="text/javascript">$(function() {
	$('.map').maphilight();
});</script>

but it returns an error…

Bug in custom code TypeError: $(…).maphilight is not a function

I can’t see anything wrong in the code…
help me, please…