Psychological phenomenon where people remember things better when they return to whatever state of consciousness they were in when they originally learned them. If you do, say, Ritalin while studying for an exam, you'll do better if you're on Ritalin again when you actually take the test.
Student 1: Dude, it's 8:30am on Tuesday-- why are you drinking a beer?
Student 2: I got hammered while I was studying for my Econ final and now I don't remember anything. I'm hoping state-dependent learning will kick in once I get a buzz on, though.