Baby brain development

Our foundations for emotional wellbeing, resilience and our ability to understand and navigate the world around us starts when we enter the world.

Experiences when we are babies, particularly relationships, shape our future development, who we become and how we thrive.

Baby Margot is just a few moments old.

She has just been born, eagerly awaited by her parents and welcomed by hospital midwives.

Just minutes previously, she was in her mother’s womb, a safe, nurturing home where all she needed was provided by her mum.

And now her little body has to adapt and survive out here in our world, with a brain roughly only half the size of an adults and undeveloped.

Margot is almost entirely dependent and vulnerable.

Babies are amazing social beings right from birth. Even though the primitive part of their brains focuses on survival, they are born ready to connect with others.

Now Margot is born, a million connections in her brain are made every second from her developing senses, from everything she sees, hears and touches.

As she senses her new world, electrical impulses fire along connections in her brain as it develops and grows.

Survival instincts help babies to feed and keep safe.

Incredibly, Margot can sense her mother’s milk supply and moves to reach it and begin breastfeeding within the first few minutes of birth. When she kisses her, Mum picks up the bacteria on Margot’s skin and makes antibodies ready to be passed on in the next feed.

Margot is comforted by her mother’s familiar heartbeat, voice and touch.

With Dad, too, his voice is comforting. She recognises it from hearing it in the womb, and she enjoys taking in his smell and voice.

She is also prepared to make connections with the other sounds and voices she’s heard in the womb, feeling reassured by connecting to her family.

Margot’s family and their friends are keen to meet her.

Her vision is undeveloped, and she cannot see far, but when close enough, she quickly starts to focus on faces and objects close to her. Miraculously, she even subtly mimics them, one way that we learn as human beings, which starts from birth.

Margot continues to instinctively move or call out when she is hungry. The primitive part of her brain continues to focus on survival.

Subtle cues, such as nuzzling or sticking out her tongue, help mum read and respond to her needs.

The part of Margot’s brain that helps her to communicate, regulate her emotions and learn is already developing, too. This is the cerebral cortex, the outside of the brain.

Baby brains are made up of over 50 billion cells, more than will ever be used, and at birth, they are unconnected. The cerebral cortex is smooth at first and incomplete. It has to grow.

As Margot begins to experience her new world, these brain cells will sprout thin tendrils seeking to make connections with other cells nearby – This is the process by which she will store her new skills and behaviours. 

Because their cortex is not yet fully developed, babies see their environment differently at first.

For Margot, at this age, just a few weeks in this world, her eyes turn light into electrical signals, but since most of the connections are missing, the cortex can’t yet construct an accurate picture.

She can’t yet combine the image from both eyes. And it’s not just sight; all of her senses are disconnected. Signals can spill over from sight to touch and smell and hearing, making the world especially strange. 

Amazingly, the baby brain can store and recognise human faces, something that helps babies to feel secure and safe surrounded by their family.

The baby brain also forces them to look at things that will improve their vision. At first, they cannot process colours, only contrasting bold patterns of simple objects and toys. The bold regular patterns generate strong regular signals which reinforces connections making them permanent.

Through trial and error and a range of stimulating experiences, Margot’s cortex is constantly rewiring, learning to recognise and understand the world around her.

Babies’ brains develop most rapidly in these early few weeks than at any other time during their lives…

While it may seem strange to think of playing with a baby this young, interacting through sensory materials, toys, and singing and letting baby enjoy the faces of those they love will help strengthen these important connections in the brain.

Babies learn most through their relationships. Depriving a baby of these opportunities can lead to much slower development and different connections being formed, leading to possible behavioural challenges in later life.

Most babies are ready to communicate with others from birth, as long as they are not poorly or premature. They want people to interact with them. As Margot grows and her vision extends, she starts to seek to attract attention and engages to practice her communication.

Her smiles gain positive responses and encourage those around her to interact with her. 

Their communication has a pattern, a Dance of Reciprocity, the to and fro of communication between baby and the other person. Both are in tune with each other, like a dance or the ‘serve and return’ of communication. 

This interaction with others is vital for development, supporting repeated connections of new tendrils in the cortex, and is their first engagement in communication that they can control.

The more Margot 'talks’ and expresses herself with her face and noises, even her arms and legs, and is responded to by the other person, then the more these connections are reinforced.

As the connections grow, there is no more room in Margot’s head for her brain to expand in, so the cortex starts to fold in on itself, making the crinkly outside of the brain that we know. 

The positive responses from those around her, encourages Margot’s learning and development. Interacting with other people literally grows her brain!

Relationships are like brain food.

The more they communicate together, the faster Margot’s brain develops, and as it strengthens, Margot is able to start to process other forms of communication.

Margot’s senses are still undeveloped, so recognising complex adult conversations is challenging, but when she is able to attract attention, her new friends turn to face her and speak more slowly, directly and in sing-song tones.

Slowing down and expressing words in this way helps baby to start to recognise simple words, tones and phrases, which will help them learn to understand those around them.

Repeating this behaviour helps baby to grow and hard wire those important connections in the cortex and sets the foundation for their ability to learn to communicate through speech as they grow.

Specialist cells called glial cells coat the connections that are used again and again, and this ‘hardwires’ them. This is how we all learn and why practising a new skill helps.

However, if a connection isn’t used, it is pruned away. In this way, the brain shapes itself to the environment around it.

In these first two years of life, Margot’s brain is growing very fast. Everything she sees, hears, touches, tastes and smells will help her brain to grow.

Everything in her environment. But especially in her relationships. The to and fro of communication helps feed babies’ brains to shape them for the future. Helping with regulating themselves, processing feelings, being in tune with others and their long-term mental health. These babies can’t speak yet, but they can certainly communicate! The relationships they have is where most of their brain development happens.

Relationships make brain food in this way throughout our lives

The next big push in brain development will happen in adolescence when hormones and further reshaping of the cortex takes place. 

But the brain carries on making new connections over our whole lifetime. Learning new things, talking with friends and family, connecting and communicating are all brain food in older adults, too.