In the Harry Potter films, Hogwarts headmaster Albus Dumbledore shows the young wizard memories that he keeps in glass vessels. The franchise portrays memories as things that possess a physical structure that can be moved around. Although they appear to look like wispy bits of fluff, they are given form and structure.

Is this in anyway similar to real life? Do memories have structure? How are they formed? To answer these questions, I spoke to Lila Davachi, who runs the Memory Lab at New York University.

I had just been reading a new publication from Davachi's team that showed how the brain is changed after the experience of some disturbing or stimulating event. This suggests that events such as the Great East Japan Earthquake can go so far as to change the brain.