science says that our brain lives for 7 minutes after our hearth stops, due to cells who die slower, and it replays moments of our lives. that's the same that happens to bellatrix lestrange after she falls in the hands of molly weasley, and suddenly she feels all those emotions she hid so well flowing back, ready to be seen in those 7 minutes. disclaimer: this is just for fun, the characters and world don't belong to me but to JKR. also english isn't my first language.