If you were feeling sad right now and you recall a sad - or, a very happy memory from the past, it will be tinged with more sadness based on your current feeling. So we felt like that was actually on solid scientific ground .
Every time you recall a memory, you're basically making another copy of it and at that same point it is susceptible to new changes and adaptations. So, you know, if you remember from when you were, you know, in second grade and there was Christmas and you got a present from your grandfather and your mom was wearing a red dress, that may or may not all have happened.
However, for story reasons, we needed to represent them in certain ways. One of the things that sort of blew me away that I didn't know when we started is that memories are completely susceptible to change. And this is, you know, one of the many reasons why certain people are trying to get it taken out - eyewitness testimony in court cases because it's very unreliable.
It might have been introduced slowly over the course of the years as you recall this memory over and over. So that was a very cool but complex idea that we thought about representing in the film but could not find a way to make it work.
We actually needed the memory - if you see the film - as a very different kind of a plot device of revealing some information to our main character. So we chose to represent it as these sort of beautiful little snow globes, which kind of, weirdly, that's the way we think of memories - at least, most of the folks that we talked to. You think of these memories as being very pure and absolute and unchanging. That's not actually real life.
The way real memories work, from what we understand, is really complex. And it's an interconnection of different things and redundancy in the brain. So the idea of a memory existing as a little snow globe - the way we represent it in the film - is actually not scientifically accurate at all.
