At some point every semester, one or more students will ask, "what causes headaches?" and/or "what causes migraines?" I usually pull out one of my posters that are not already on the wall about the topic (the second edition is to the right--my poster is the first edition from anatomical.com http://www.anatomical.com/product.asp?pn=9780781776592). Most texts that I've seen rarely deal with the subject since it's more medical than psychological.
Today, while on facebook, PBS offered this little article about migraines. It also had a wonderful little graphic--I love how artists are increasingly making incredible looking graphics related to the body and brain.