I go through that exact same thing, altho my subjects of interest are not nearly as intellectual as yours. Mine, are urban legends, like Dracula ( where I try to accertain when, where and by whom these tales were started) uhm, the salem witch hunt, correlations between ancient paganism and modern day Christianty, ancient Egypt, The occult, famous serial killers ( I NEED to know WHY they committed their crimes) nephilum (sp) Well I'm sure you get the idea I research for as long as my interest holds, which is the length of my hypomania. After my mood shifts, I retain most of the info I devoured, but don't have any interest to persue the subject any further... Btw I'm not ADD altho I am BPII ... Just wanted you to know you're not alone