This Is MS Multiple Sclerosis Community: Knowledge & Support

never noticed this mri site before. it's an ms brain. or if you just go back as far as aanlib in the URL you can see all the other kinds of brain mris they have. on the ms brain (with tour) - that's the link below - if you find the right vertical slice, then you can move along the timeline from left to right and watch for changes. here and there there's some explanation of what you're looking at.
http://www.med.harvard.edu/AANLIB/cases/case5/mr2/020.html