Visual literacy is part of the art of communication and design. When designing for any learning event, the ability to communicate the content and interpret it are vital to understanding.
The following links will provide a start for visual literacy study.
http://www.visual-literacy.org/periodic_table/periodic_table.html
There are more maps here:
http://www.visual-literacy.org/pages/documents.htm
including the page by Chris the extracts each one with a show/hide
http://www.cems.uwe.ac.uk/xmldb/rest/db/Visualization/showAll.xql
and the papers:
http://www.visual-literacy.org/pages/articles.htm
As long as you are looking at visual lit, there is an ivla
http://www.ivla.org/
http://www.ivla.org/resources.htm
which has a taxonomy and bibliography listed
http://www.adobe.com/uk/education/pdf/adobe_visual_literacy_paper.pdf
http://www.pomona.edu/Academics/courserelated/classprojects/Visual-lit/intro/intro.html
http://trc.ucdavis.edu/?page_id=823
lots here:
http://www.gslis.utexas.edu/~vlibrary/edres/pathfinders/atos/
http://www.jakesonline.org/visual.htm
http://www.jakesonline.org/collections.htm
http://suelebeau.com/visualliteracy.html
http://www.kn.pacbell.com/wired/21stcent/visual.html
http://www.ericdigests.org/2003-1/visual.htm
