COWEN: There’s an old saying that we “think with our gut.” Do you attach any credence to this? Is there some broader process of computation going on when we think that’s not just in our brain?
BOYDEN: Well, we’ve now realized as a community — my group doesn’t work on this yet, but it’s a very exciting area — that the brain is almost like part of an ecosystem that you could call the body, and the whole body is computing together.
Maybe over the time course of several seconds, when you have an individual thought or feeling, maybe a lot of that is contained within the brain. But if you go beyond that time scale, there might be microbes in the gut that secrete molecules that can actually get into the brain and modulate complex functions, like maybe even social behavior, some people think.
COWEN: Does that mean whole-brain emulation is impossible, then? You basically have to reproduce the body?
BOYDEN: It’s a good question. One possibility is that, if you are emulating the brain, maybe you can run the simulation for a short period of time. But if you want to integrate all the changes that are due to the rest of the body to encompass more complex things, like long-term emotions or moods, you might call them, or memory or personality, you might have to think about the body as an ecosystem.
Then there’s also the concept of extended intelligence, where I’m not just me. If I’m getting out of bed in the morning and getting dressed and having my cup of coffee, that’s one version of me. But then when I get up on a stage to lecture for my class, or if I go and hang out with friends, maybe certain parts of my personality are expressed and other parts are not. I think we all experience this all the time, where we’re part of an ecosystem of people as well.
To learn more of Boyden’s work I recommend watching his talk on Edge.org.