Understanding Your Child’s Brain - Part 4

This is the fourth article in a four-part series exploring brain development and children’s behaviour. Together, we’ll look at some of the brain systems involved in survival, emotions, thinking and self-regulation, and how understanding them can help us respond to children with greater empathy and more realistic expectations.

REPTILE → MAMMAL → HUMAN → INTEGRATION

PART 4 OF 4 — INTEGRATION: HOW THE BRAIN SYSTEMS WORK TOGETHER

🔗 INTEGRATION — ALL OF THESE SYSTEMS COMMUNICATE AND WORK TOGETHER

→ Survival and automatic regulation systems

→ Emotional and memory networks

→ Prefrontal and other interconnected cortical networks

→ Communication between the body, emotions, thoughts and environment

→ The developing capacity to regulate, reflect, adapt, connect and respond

A NOTE BEFORE WE BEGIN

The terms “reptile brain,” “mammal brain” and “human brain” are sometimes used as a simple way of explaining different brain systems and their functions. Modern neuroscience tells us that the brain is much more interconnected than this, and these systems do not work as three separate brains. They communicate and influence one another constantly.

In this series, I have used these terms as a simple framework for understanding some of the major systems involved in children’s behaviour, while drawing on contemporary neuroscience to explain what is actually happening.

In this final part, we will bring these ideas together and explore how the different brain systems communicate, influence one another and work together as a whole.

So, let’s look at what happens when survival, emotion and thinking come together.

FROM THREE SYSTEMS TO ONE DEVELOPING BRAIN

In the first three parts of this series, we explored the systems involved in survival, emotion and thinking.

These systems are sometimes described as the “Reptile Brain,” “Mammal Brain” and “Human Brain.” But remember, these are not three separate brains. They are different ways of understanding some of the interconnected systems that make up our brain.

Our brain is constantly communicating with itself.

The systems involved in survival help us respond to what is happening in our environment. The

systems involved in emotion help us experience feelings, connect with others and make sense of what matters to us. And the systems involved in thinking help us plan, reflect, solve problems and make decisions.

Integration is about how these systems work together.

WHEN THE SYSTEMS WORK TOGETHER

Imagine your child is playing happily when another child takes their toy.

Their survival systems may respond to the sudden change or sense of threat.

Their emotional systems may experience frustration, disappointment or anger.

And their thinking systems may gradually help them consider what to do next.

But these systems don't take turns like a queue.

They are communicating and influencing one another all the time.

The way your child feels can affect their attention and thinking. Their thinking can help them make sense of their feelings. And when they feel safe and supported, they may have more access to the skills they are still developing.

This is why we can't always understand a child's behaviour by looking at just one part of the brain.

The whole system matters.

And this is also why a child who can usually manage something may struggle with it when they are tired, hungry, overwhelmed or emotionally flooded.

Their thinking skills haven't necessarily disappeared. The demands on their developing systems may simply be greater than they can manage in that moment.

INTEGRATION IN EVERYDAY LIFE

Integration is not something children either have or don't have. It is a developing capacity, and it can look different depending on what is happening around them.

A child might be able to use their thinking skills beautifully when they are calm, rested and supported. But when the same child is tired, hungry, overwhelmed or frightened, those skills may be harder to access.

This is why we can see such different behaviour from the same child in different situations.

And it is why “But they can do it at home!” or “They know the rule!” doesn't always tell us what they are capable of in that particular moment.

The question is not only “What does my child know?”

It is also:

“What is happening in their body, emotions and environment right now?”

“What demands are being placed on their developing brain?”

“What support might help them access the skills they are still learning?”

WHEN THINKING ISN'T ENOUGH

Imagine a child who is building a tower with blocks.

They are concentrating, planning where each block should go and adjusting their ideas when something doesn't work.

Their thinking systems are helping them organise information, solve problems and work towards a goal.

But then another child knocks the tower over.

Suddenly, the situation changes.

The child may feel disappointed, frustrated or angry. Their body may become activated, and their attention may shift towards what has just happened.

The same thinking skills that were available a moment ago may now be much harder to access.

They might push the other child, cry, shout or say:

“You ruined it!”

This doesn't mean their thinking brain has stopped working.

It means that their emotional and survival systems are influencing what is happening in the moment.

And this is where our understanding of integration becomes so useful.

Instead of seeing the behaviour as simply “They know better, but they chose not to,” we can begin to ask:

“What happened to their ability to access the skills they were using a moment ago?”

That doesn't mean we ignore the behaviour.

It means we try to understand what the behaviour is communicating, while still supporting the child to learn what to do next.

CO-REGULATION: HELPING THE SYSTEMS WORK TOGETHER

When children become overwhelmed, their thinking skills may be harder to access. This is when co-regulation becomes especially important.

Co-regulation is the process of helping a child feel safe, supported and organised through our relationship with them. It does not mean doing everything for them. It means providing the support they need while their own regulation and thinking skills are still developing.

Let’s return to the example of the child building a tower with blocks.

Another child comes along and knocks it over.

Your child may feel frustrated, disappointed or angry. Their body may become tense, their voice may get louder, and they may push the other child or shout:

“You ruined it!”

In that moment, the first step is not necessarily to explain why pushing is wrong or ask them to think of a solution.

Their emotional and survival systems may be highly activated, making it harder for them to access the thinking skills they are still developing.

Instead, we can begin by helping them feel safe and supported.

For example, we might say:

“You worked really hard on that tower, and now it has fallen down. It wasn’t fair that your friend knocked it over. I can see why you’re upset.”

“I won’t let you push, though. I’m going to help you keep everyone safe.”

These words acknowledge the child’s experience while maintaining a clear boundary.

We are not saying that pushing is okay. We are helping the child understand that their feelings are allowed, but hurting someone is not.

We are also recognising that the other child’s actions matter. Supporting one child does not mean ignoring the needs or feelings of the other.

If the child is still very overwhelmed, we may need to use fewer words:

“You’re safe. I’m here.”

“That was really hard.”

“Let’s take a little space.”

We might move closer, reduce the number of people talking, offer a quieter space or simply stay nearby with a calm presence.

Once the child is beginning to settle, we can gradually help them reconnect with their thinking skills.

For example:

“You were angry because your tower was knocked down. You wanted to keep building.”

“Your friend needs to be careful with your building, too.”

“Next time, you can say, ‘Please don’t knock it down,’ or ask me for help.”

“And if you push, we need to check that your friend is okay.”

If the other child is ready, we might also support repair:

“Your friend was upset when you pushed them. Let’s check that they’re okay.”

“What could we do to help make things right?”

This might mean helping the child apologise, checking on the other child, rebuilding the tower together or finding another way to continue the play.

The goal is not to make the child calm down as quickly as possible.

The goal is to help them move from being overwhelmed towards being able to feel, think and respond with support.

And over time, the words and strategies we use with them can gradually become words and strategies they learn to use for themselves.

Co-regulation is one of the ways children begin to develop self-regulation.

FROM CO-REGULATION TO SELF-REGULATION

Children do not develop self-regulation simply because we tell them to calm down. They develop it through repeated experiences of being supported, practising skills and gradually discovering that they can manage more for themselves.

Over time, children gradually become more able to use the skills they have been practising with support.

They begin to recognise their feelings, pause, consider their options and make choices.

But this development is gradual, and it doesn't happen in a straight line.

A child may be able to do something independently one day and need more support the next.

That is part of development.

And it is why we need to think about capacity, not just behaviour.

WHAT THIS MEANS FOR OUR EXPECTATIONS

Understanding integration does not mean we stop having expectations of children.

It means we become more thoughtful about what we ask them to do, when we ask them to do it, and what support they may need.

We can hold boundaries, teach children that feelings are allowed but hurting others is not, and help them repair relationships when something goes wrong.

At the same time, we can recognise that their ability to manage these expectations is still developing.

Sometimes this means making the expectation smaller, offering more support, or giving the child another opportunity to try when they are ready.

Understanding the developing brain helps us teach children in a way that is both compassionate and appropriately challenging.

Children will still make mistakes. They will still hurt others, break things and need to repair relationships when something goes wrong.

Understanding their developing brain does not remove the need for boundaries or responsibility. It helps us teach these things in a way that is more likely to be understood, practised and remembered.

We can hold children accountable while also recognising that learning to manage big feelings, pause, adapt and make thoughtful choices takes time.

Children will still make mistakes. They will still hurt others, break things and need to repair relationships. Understanding their developing brain does not remove the need for boundaries or responsibility. It helps us teach those things in a way that is more likely to be understood and remembered.

THE BRAIN IS BUILT THROUGH RELATIONSHIPS

One of the most encouraging things about the developing brain is that children are not expected to figure all of this out on their own.

They learn through relationships.

They learn through experience.

They learn through play.

They learn through opportunities to practise.

And they learn through the repeated experience of being supported when things are difficult.

When we help a child pause, we are supporting the development of inhibition.

When we help them remember the steps, we are supporting working memory.

When we help them find another way, we are supporting flexible thinking.

When we stay alongside them while they experience a big emotion, we are supporting their developing capacity to regulate.

Little by little, these experiences become part of what your child can do for themselves.

BRINGING THE SERIES TOGETHER

So, what have we learned?

🦎 REPTILE — SURVIVAL & AUTOMATIC REGULATION The systems involved in keeping us safe and responding to what is happening around us.

🐾 MAMMAL — EMOTION & EMOTIONAL LEARNING The systems involved in feeling, connecting, remembering and making emotional sense of our experiences.

🧠 HUMAN — COMPLEX THINKING & EXECUTIVE FUNCTIONING The systems involved in planning, problem-solving, inhibition, flexible thinking and other complex cognitive abilities.

🔗 INTEGRATION — ALL OF THESE SYSTEMS COMMUNICATE AND WORK TOGETHER.

And this is the part I hope stays with you:

Your child is not three separate brains. They are one developing brain, with different systems communicating and influencing one another.

When we understand that, we can begin to see behaviour differently.

Not as a simple question of “Will they?” or “Won't they?”

But as a question of:

“What is happening in their developing brain, and how can I support them?”

And perhaps that is one of the most important things we can offer children:

The opportunity to grow, learn and develop, with the support of relationships that help them feel safe enough to do so. 💚

REFERENCES

National Scientific Council on the Developing Child. Building the Brain’s “Air Traffic Control” System: How Early Experiences Shape the Development of Executive Function. Working Paper No. 11. Center on the Developing Child, Harvard University.

Center on the Developing Child at Harvard University. A Guide to Executive Function.

Center on the Developing Child at Harvard University. Three Principles to Improve Outcomes for Children and Families.

Center on the Developing Child at Harvard University. Brain-Building Through Play: Activities for Infants, Toddlers, and Children.

Siegel, D. J., & Bryson, T. P. The Whole-Brain Child.