Why your brain is hungry for more play, according to a child development expert

Every waking moment, billions of neurons bustle across the highways of our brains, choreographing the body's thoughts, movements and communications. Newborns come into the world with 100 billion neurons and develop over one million new neural connections every second during their first years of life as they begin to experiment with the world around them — rolling in the dirt, sticking nearly everything in their mouths and observing how the power of their cries can manipulate the adults around them. 

Through these experiences, children start to develop patterns that have implications for their adult lives. An infant learns that in most cases, crying will get their caregiver's attention. They start to reach for sweets instead of sand when they want a snack and learn to talk so that they can better communicate their needs. Over time, the brain develops patterns that help its executive functioning operate more efficiently — but research shows that breaking those cycles and entering a state of play can have just as many beneficial impacts, helping children improvise and respond creatively to new experiences as they grow up.

For the past decade, Jacqueline Harding, Ph.D., a child development expert at Middlesex University, has observed thousands of hours of play, monitoring children's posture, body language and facial movements change the moment they lose themselves in a game. Harding's new book, "The Brain That Loves to Play," is a starter guide in fostering play. We talked with her about what's going on in the brain when the mind plays, how that shapes a child's future self and how adults can tap back into a sense of playfulness if they feel they've lost it. 

This conversation has been edited for length and clarity.

Can you explain what's going on in the brain on the inside, when play is going on on the outside? 

Imagination can turn genes on or off inside the nerve cells, which then creates proteins that change the structure, the architecture, of the brain. Humans are open systems, particularly when they're young. They want to engage, they want to explore, and they use their senses [to do so]. It's all about the sensory pathways.

When I talk about quality play experiences, I'm talking about sensory-driven experiences like sand, mud, water — all the stuff that's really dirty and grungy that most of us, as parents, run away from. But actually, this is what children really need, they need to get out into the world and experience it for themselves through their eyes, through their hearing, through the smell, through the taste. The brain is hungry for that. Those are nutrients for the brain. 

Many chapters of the book are dedicated to specific ages of development. How does play change over time? Can you describe the "play history," and how that shapes our adult lives?

Play histories are personal and unique to all of us. They impact us as we mature in very subtle ways. This is the downside: It's very difficult to put right, as time goes, any deficit in play, or prevention or absence of something they particularly need. I had a friend who was super bright and helped [build body scanning technology]. To this day, he resents his job, because when he was younger, his parents wanted him to study in order to become a scientist. But he didn't get what he needed. Yes, he's super bright. But his play history was so depleted that it didn't meet an emotional need in him, and he's still looking for that today. That's kind of what I mean by how it's almost like a history book of your life. It's very unique to each of us. Is it kind of a diary, if you think of it like that.

Your question to me around how does play change as children develop, that's really about their developmental stage, it's about what they can understand and what they're interested in at that time. We have schemas where children may be interested in tipping things out and putting them back in again, or it could be that they have an enclosure schema where they're going through a fascination of hiding or building something. That meets a particular need at that time. Their interests change as time passes, and of course, their ability to connect with others will determine how they play. 

Solo play starts at the beginning and continues for life. Then you have the onlooking play, where they're beginning to think, "Hm, I wonder what somebody else is doing." And then parallel play when they're playing alongside someone else. Then you get cooperative play, where they're going, "Okay, you and I are in this together." Then you get the complex cooperative play where they're assigning each other's roles to each other, and that will continue for life.

I guess when you're zero days old, everything is new, and over time, it gets less new. How does that change or influence the way that we play, and does that make us less playful as adults?

It's more of a mental attitude. If we become bored with life, if we're not willing to see the new, if we're not willing to engage in the novel, if we're not willing to do something different, we'll be bored. You can shake up your own brain by walking backward. If you do that, just once a day walk backward, it begins to jolt the brain into a different place where it's thinking, "Life can look different." Or you stand on your head and you see something different, or you try a new hobby, you see the world from a different point of view, you have a different smell, you cook something different. 

As we age, we absolutely need to keep up that childlike view of the world. Because the ability to develop new neurons, we need that throughout life. We can prevent some of the aging process by being engaged, staying engaged, staying childlike, staying playful, staying with humor and laughing a good belly laugh. If you have a problem one day, you put it aside, watch your favorite comedian on television, have a laugh, and then look at the problem that you had before, you'll find that you see it in a slightly different light because the brain becomes more open, more receptive and more keen to solve problems. 

Now, one of the most important points I think I'm making in the book is that our generations and generations before us have caused significant problems for the world. What sort of child would you want to develop? What skills would you want children to develop in the future? You'd want them to be problem solvers, you'd want them to be creative. You want them to be resilient. Creative pursuits right from birth are going to be the kind of nutrients for the developing child to help humanity. We can go on the internet and learn facts. What we can't learn from the internet is the ability to be problem solvers, so that's something that we need to help young children develop.

Sometimes children "play" with video games online or with smartphones. In the book, you call this "digital play." Does that activate some of the same things as some of these tactile things that you're talking about? How does digital play affect development?

The jury's out, to be honest, around the negative impacts of digital play. Now, there's no doubt that the majority of digital play is sedentary. … If children are sitting in front of television programs and video games for hours on end, it's not going to do anybody any good. However, we're still researching, we still need to know much more about how it's impacting the developing brain. Some of that interaction they're getting from screens and games, if they're well-researched, as some of the children's TV shows are … they can help. 

Is it the same as children outdoors, feeling the sand and water? Absolutely not. Is it a different experience? Yes. Can it be novel and exciting, challenge their thinking, and help teach things like vocabulary? Absolutely. But we're talking about limited amounts of time, and my emphasis will always be on sensory development. Children should be hands-on, smelling, seeing, interacting.

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Some of the things that you're saying really remind me of the "flow state," which I'm sure you're familiar with. What are some differences or similarities between this flow state and play? 

You're talking about Mihály [Csíkszentmihályi's] work. It's just a beautiful state of timelessness, a bubble, where you're absorbed in this space. That happens to adults as well as children. When children enter that state where everything sort of slows down and they're much less aware of anything else that's going on around them. 

What happens, and this is when I built on [Csíkszentmihályi's] work, there comes this "aha" moment. What we observed is that at that moment, the child will want to share the experience, and time and time again, when we caught it on film, this child would be absorbed in making a model out of paper [or something like that], they've risen to that "aha" moment and they want to share it. The child would rush to an adult: "Let me show you what I've done."

How would you recommend that adults kind of tap back into that sense of playfulness, if they feel like they've lost it?

Do something different every single day. Challenge yourself. Walk backward. Go and see something you've never seen before. Lie on the floor in the forest and look up and see things differently. Take up a new hobby, nothing expensive. Use paint in a different way. It just moves you into a different space in your thinking and kind of pushes everything else aside. It's as though you clear the way for a better mental state. 

if you're a parent, it's going to be good for you and it's going to be good for the child as well. Because it brings with it that optimism. We all know what it feels like when somebody comes into a room and it's almost like they come in with this heaviness. Nobody wants that. What children want from adults is for their eyes to light up when that child comes into the room. That communicates self-worth, and you can't give that to someone unless you've had that moment of self-worth and self-belief by engaging in creativity and the novel and the new. Stay interested. Stay curious. Keep wondering. 

There's a lot of research showing how adverse childhood experiences can have lasting effects on the body. If you start playing in communal settings, and you start to get a negative self-image, for example, how does that get rooted into the brain, and what power does the brain have to reverse it?

Norman Doidge says it so beautifully: "The brain can change itself." I'm certainly not of the belief that, if there are negative play experiences, you're stuck with that for life. What you do need when you're young are sensitive adults who notice these things and go, "Tell me about what happened. How are you feeling today?" You need adults to help guide the child towards a place where they can begin to think differently about themselves.

I believe the same as Doidge. We can regenerate. If you've got to 10 years of age, and you've had a lot of negativity, it's just going to be tougher. Not impossible, just tough, and that's not what we want. We really want adults who are tuned in watching and understanding. If you change the beginning, you can change the whole story. 

How has play been studied in other species, and what can that tell us about our own development? 

It's very difficult to tell whether [other animals] can experience the same level of imagination and creativity as humans. I think we don't really know [other species'] ability to imagine, to dream, to create. There's definitely evidence of problem-solving and play that prepares for survival. Humans also play for survival, but they also play for play's sake. We definitely see animals just playing for play's sake, just the same as children as well.

So play is a means of survival, in that it relaxes the neural network, and is evolutionarily advantageous?

Absolutely. But I don't want it to be reduced just to something that is survival or preparation for adulthood. Why can't we value play for play's sake? Yes, it's a biological drive. But isn't it pleasurable too, most of the time? Reducing play to something that's just preparation for adulthood, seems terribly disappointing, doesn't it? I suppose we're talking about survival, and in a way, you're talking about what it's doing to the body but I kind of still feel that it has a value of its own, and that it's unique, and that it's not just all down to preparation for adulthood. 

What's delightful about children is, that children live in the moment. When we look back, we don't remember days, we remember moments. We remember those little bits with color and texture. It is that in-the-moment experience that children are able to do moment by moment by moment. And that is something that we can recapture as adults as well.