Brain fog has been described as one of long term impacts of COVID-19 —but what’s actually happening within our brains and why is it so hard to remember what happened just last week?
In his latest book “Livewired: The Inside Story of The Ever-Changing Brain” neuroscientist David Eagleman explains that our brains are constantly changing and reconfiguring to the world around us. The more experiences we have, the more the brain absorbs — and the more it adjusts. Eagleman explains that when we are born our brains are extremely malleable and able to learn language and absorb information incredibly fast but surprisingly as we age our brains actually retain that malleability,as long as we provide them with stimuli and novel experiences.
KCRW’s Jonathan Bastian talks with Eagleman about his latest research into the workings of the brain.
The following interview excerpts have been abbreviated and edited for clarity.
KCRW: In your new book you talk about the unique nature of the brain and use words like plasticity, malleability; can you explain what those words mean?
David Eagleman:”In the book ‘Livewired’ I define this new term ‘liveware’ and the reason I do is because we're completely used to talking about hardware and software - that's how we build all of our current devices. But the brain is doing something very different in that it changes its own hardware on the fly all the time.
About 100 years ago, the great psychologist William James coined the term ‘plasticity’ — he was referring to why we call the material plastic, ‘plastic’ because you can mold it into a shape and it holds that shape.
The reason I'm suggesting that that term might be outdated for us now, is because what the brain is actually doing is constantly plugging in and re-plugging in and changing connection strengths; with over 86 billion neurons and each one of these has about 10,000 connections to its neighbors — hundreds of trillions of connections in the brain. Your whole life your brain is constantly reconfiguring its circuitry, it's a living dynamic electric fabric that is so huge, it's totally mind boggling to us. You can't possibly wrap your arms around that.
So the days of thinking that you're molded into a shape and then hold on to that shape are gone as it’s actually a much bigger thing than that. I'm calling this ‘liveware.’. What is so remarkable is we're all walking around with three pounds of this technology in our skulls but we don't actually have any capacity to build technology like this now.
My goal in this book was to distill down everything we know into some basic principles about what the brain is up to so that this can be a turning moment in history where engineering starts drafting off of neuroscience and we build a completely new generation of machines.”
Describe how the human brain is able to morph and to create new pathways versus anything we see in nature with the brains of animals for example?
Eagleman: ‘Humans represent the most extreme version of brain plasticity. So all animals have brains that are live wired to some degree. So for example, I can teach my dog a trick and then she can figure it out and do it that way. Obviously, it's easier with young dogs as the expression goes. But humans are especially plastic; we drop into the world so malleable, that as a result we have these incredibly long infancies, way longer than any other species to reach adolescence.
If you watch let's say a zebra or a giraffe born, they're walking within forty five minutes, they wobble up on their little legs and then they're running around. But you've probably noticed that with human babies, it doesn't take forty five minutes it takes a little longer and that's because we represent the most malleable species and as a result, we've taken over every corner of the planet and we've even gotten off the planet.
We've invented the internet, we've cured all kinds of things and so it’s a terrific trick. We drop into the world, malleable and we absorb everything around us, our culture, our beliefs, our languages and that allows us to not have to start over, the way that an alligator does when it's born into the world, essentially doing everything from scratch.
When a child drops in the world, they inherit all of the inventions and culture and learning and knowledge that have come before them. So they get to springboard right off this launching pad, right from the first moment, simply by having a brain that's willing to absorb what's going on around it.”
In the book you describe a “use it or lose it” nature of the brain. Give some examples of what happens when the right external stimuli are not there?
Eagleman: “It turns out this is a gamble on Mother Nature's part, to expect that all the proper stimuli are there for developing the brain. It works almost all the time but occasionally you get one of these tragic cases where a child is so deeply neglected that they're not getting the proper input. They're not getting the language, not getting the touch and the love and we see what happens with their brains if they don’t develop correctly.
In Romania, after the fall of [Communist leader Nicolae] Ceausescu there were tens of thousands of kids who ended up in orphanages because their parents had been killed. The staff were completely overwhelmed, so they said don't touch the kids, don't talk to the kids because otherwise they'll get clingy. And so that's what they did. All these children were raised in an environment where they weren't getting the proper kind of input and they all ended up with really bad cognitive deficits as a result. Abused children who have essentially literally been locked in a room have terrible deficits; they can't speak, they don't have proper vision, they can't chew solid food, they never get the rules of grammar, even after they're rescued and given all the care and attention in the world. There's a certain window of time when you can become you and you can develop your cognitive skills. And once that passes, it's too late.”
What are the implications for raising children; what are the right stimuli for raising a child today?
Eagleman: “My wife is also a neuroscientist and we're always thinking and talking about this issue and there are some useful lessons about raising a child that come from neuroscience. I get asked all the time about raising kids today, in a digital age when they have access to the internet all the time and I have to tell you I am completely a cyber optimist about this. It is so wonderful, not for kids to waste a ton of time on screens, but just to have access to the world of knowledge, in a way that I did not growing up.
When I grew up and wanted to know something, my mother would drive me down to the library, 20 minutes away, I would pull out an Encyclopedia Britannica and try to find the article. Hopefully if they had the article, but maybe it was 10 years old and outdated, But today’s children, the moment they're curious about something, they can get the answer instantly. And it turns out from a brain point of view, this is extremely useful because you have the right cocktail of neurotransmitters present when you are curious. And so if you get the answer in the context of asking the question, it will actually stick with you because you have better plasticity as opposed to, when I was growing up, I learned lots of ‘just in case’ information; ‘just in case’ I ever need to know these dates etc., but today’s kids now have lots of ‘just in time’ information.
This doesn’t have to do just with screens. We have an Amazon Alexa and Google Home, in the house and my kids constantly are asking questions; they ask a question and they get the answer. This is a terrific way for a child to be able to dive into the sphere of human knowledge from any entry door that they want from whatever they're curious about, it the moment and then they think, wow, that's interesting, that's weird and so then they ask the next question. With each question they dive deeper and deeper into that sphere, but they've gotten there via some pathway that's meaningful.
As long as a parent makes sure that the kid isn't spending all the time on the screen, but also doing physical things and I'm very optimistic about where this is going. Kids in the next generation are going to be clearly and significantly smarter than we are. The reason I say this is because I run into kids all the time who say something that’s really smart and ask them how they knew that and they say ‘Oh, I watched a TED talk’ on that.
When I grew up I had the homeroom teacher and that's where I got my information. But now a kid can watch the best person on the planet give the best talk of his or her life in 15 minutes with beautiful visuals and it just speeds things up in a terrific way.”