Anger is about fairness. If it feels that you're getting ripped off or taken advantage of, that's when anger comes up. Sadness deals with loss. And I suddenly had this new revelation - it felt like to me - that those are all true, but the real, deeper reason we have emotions is to connect us together. And that felt big to me.

One of the other experts we consulted with, this guy named Dacher Keltner, he was big on sadness as community bonding - I think is the word he used.

It's like you run into this dark tunnel, trusting that somewhere there's another end to it where you're going to come out. And there's a point in the middle where it's just dark. There's no light from where you came in and there's no light at the other end; all you can do is keep running. And then you start to see a little light, and a little more light, and then, bam! You're out in the sun.

There's something really emotional about not having any sound. That allows, I think, the audience to participate more actively and kind of imagine what are they talking about there?

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.

Yeah, we were looking for a way to represent adulthood and the passing into adulthood. And I think, for me personally and a lot of the folks that I work with, childhood is kind of a sacred, special kind of point in time that has a real joy and purity to it. And we sort of long on a daily basis to reach back and kind of grab onto that in some way.

You know there's always that kid in your class — and every class has one — the kid who draws all the time and is really good? That was not me. I was a lousy draftsman. But as soon as I figured out that I could make things come alive, like using the corners of my math book to make flipbooks, I was hooked.