‘If you’re thinking about intelligence, there’s a real genuine tradeoff between your ability to explore as many options as you can versus your ability to quickly, efficiently commit to a particular option and implement it. And it turns out that even if you just do the math, it’s really impossible to get a system that optimizes both of those things at the same time, that is exploring and exploiting simultaneously because they’re really deeply in tension with one another. And the way that computer scientists have figured out to try to solve this problem very characteristically is give the system a chance to explore first, give it a chance to figure out all the information, and then once it’s got the information, it can go out and it can exploit later on. So, explore first and then exploit. And I think that evolution has used that strategy in designing human development in particular because we have this really long childhood. But I think you can see the same thing in non-human animals and not just in mammals, but in birds and maybe even in insects. So you see this really deep tension, which I think we’re facing all the time between how much are we considering different possibilities and how much are we acting efficiently and swiftly. There’s, again, an intrinsic tension between how much you know and how open you are to new possibilities. So, again, just sort of something you can formally show is that if I know a lot, then I should really rely on that knowledge. And I should, to some extent, discount something new that somebody tells me. Whereas if I don’t know a lot, then almost by definition, I have to be open to more knowledge. But I think it’s more than just the fact that you have what the Zen masters call beginner’s mind, right, that you start out not knowing as much. I think we can actually point to things like the physical makeup of a child’s brain and an adult brain that makes them differently adapted for exploring and exploiting.
So there’s two big areas of development that seem to be different. So one of them is that the young brain seems to start out making many, many new connections. So what you’ll see when you look at a chart of synaptic development, for instance, is, you’ve got this early period when many, many, many new connections are being made. And then you’ve got this later period where the connections that are used a lot that are working well, they get maintained, they get strengthened, they get to be more efficient. And then the ones that aren’t are pruned, as neuroscientists say. They kind of disappear. The consequence of that is that you have this young brain that has a lot of what neuroscientists call plasticity. It can change really easily, essentially. But it’s not very good at putting on its jacket and getting into preschool in the morning. It’s not very good at doing anything that is the sort of things that you need to act well. And it’s especially not good at things like inhibition. It’s especially not good at doing things like having one part of the brain restrict what another part of the brain is going to do. So that’s one change that’s changed from this lots of local connections, lots of plasticity, to something that’s got longer and more efficient connections, but is less changeable. The other change that’s particularly relevant to humans is that we have the prefrontal cortex. That’s the part of our brain that’s sort of the executive office of the brain, where long-term planning, inhibition, focus, all those things seem to be done by this part of the brain. And what happens with development is that that part of the brain, that executive part gets more and more control over the rest of the brain as you get older. So that the ability to have an impulse in the back of your brain and the front of your brain can come in and shut that out. Or there’s a distraction in the back of your brain, something that is in your visual field that isn’t relevant to what you do. And the frontal part can literally shut down that other part of your brain. But that process takes a long time. So when you start out, you’ve got much less of that kind of frontal control, more of, I guess, in some ways, almost more like the octos where parts of your brain are doing their own thing. And then as you get older, you get more and more of that control.
So those are two really, really different kinds of consciousness. One kind of consciousness — this is an old metaphor — is to think about attention as being like a spotlight. It comes in. It illuminates the thing that you want to find out about. And you don’t see the things that are on the other side. And I think that in other states of consciousness, especially the state of consciousness you’re in when you’re a child — but I think there are things that adults do that put them in that state as well — you have something that’s much more like a lantern. So you’re actually taking in information from everything that’s going on around you. And the most important thing is, is this going to teach me something? Is this new? Is this interesting? Is this curious, rather than focusing your attention and consciousness on just one thing at a time. So, a lot of the theories of consciousness start out from what I think of as professorial consciousness. So, surprise, surprise, when philosophers and psychologists are thinking about consciousness, they think about the kind of consciousness that philosophers and psychologists have a lot of the time. And that sort of consciousness is, say, you’re sitting in your chair. You have the paper to write. You’re desperately trying to focus on the specific things that you said that you would do. And then you kind of get distracted, and your mind wanders a bit. And you start ruminating about other things. And that kind of goal-directed, focused, consciousness, which goes very much with the sense of a self — so there’s a me that’s trying to finish up the paper or answer the emails or do all the things that I have to do — that’s really been the focus of a lot of theories of consciousness, is if that kind of consciousness was what consciousness was all about. And we even can show neurologically that, for instance, what happens in that state is when I attend to something, when I pay attention to something, what happens is the thing that I’m paying attention to becomes much brighter and more vivid. And I actually shut down all the other things that I’m not paying attention to. You can even see that in the brain. So the part of your brain that’s relevant to what you’re attending to becomes more active, more plastic, more changeable. And the other nearby parts get shut down, again, inhibited. So there’s a really nice picture about what happens in professorial consciousness. That’s kind of how consciousness works. And again, maybe not surprisingly, people have acted as if that kind of consciousness is what consciousness is really all about. That’s really what you want when you’re conscious. And what I would argue is there’s all these other kinds of states of experience — and not just me, other philosophers as well. There’s all these other kinds of ways of being sentient, ways of being aware, ways of being conscious, that are not like that at all. So, one interesting example that there’s actually some studies of is to think about when you’re completely absorbed in a really interesting movie. You’re kind of gone. Your self is gone. You’re not deciding what to pay attention to in the movie. The movie is just completely captivating. In the state of that focused, goal-directed consciousness, those frontal areas are very involved and very engaged. And there seem to actually be two pathways. One of them is the one that’s sort of here’s the goal-directed pathway, what they sometimes call the task dependent activity. And then the other one is what’s sometimes called the default mode. And that’s the sort of ruminating or thinking about the other things that you have to do, being in your head, as we say, as the other mode. When you look at someone who’s in the scanner, who’s really absorbed in a great movie, neither of those parts are really active. And instead, other parts of the brain are more active. And that brain, the brain of the person who’s absorbed in the movie, looks more like the child’s brain.’ (from the New York Times)
I had initially thought to break this part of the transcript into smaller pieces, but I figured they all go together, and hopefully you find this subject as interesting as I do. I’m happy to try to manifest the child-like side of my brain as often as I can.