How Our Brains Grow – Ruby Wax.

Evolution plays its part in creating an experience dependent brain in that you are born inside out (don’t panic it all works out) so when you’re only a one month old embryo, your outer layer of cells folds inward forming your brain stem and this is why our insides were once literally connected to the outside. The DNA instructs the neurons on which area they should migrate to. They then connect to each other, based on your experience and that ultimately will determine how your brain is shaped.

Only the strong and often used neurons survive and the rest die off, like sperm that don’t make it through the big swim.

Somehow every single cell has to know if it’s a cell for your nose or part of your toenail and find its way to that particular area. No satnav, no nothing. Can you imagine that kind of a challenge? Trillions of cells trying to put together the puzzle of all your parts; what makes you you. It would be like rush hour, squared.

What are the chances that you come out vaguely normal and not looking like a Picasso with three breasts coming out of your forehead? I wouldn’t bet on the odds. And let’s say you form the full complement of limbs and digits and a brain that works, now you depend on your parents, two descendants of a one-celled amoeba, to fill your tiny empty brain with the first spoonfuls of knowledge; teaching you to talk, walk, think, feel, flirt and freak out. This is why each of us, each generation, has to struggle with this universal quandary: what are we supposed to be doing here?

Reptiles lay some eggs or just stand and deliver and move on; without sentimentality they walk away to mate again somewhere with anyone who happens to be mounting them at the time while they’re munching on some lawn. Then the baby automatically knows how to swim, slither, trot or fly away. We are born knowing nothing and just lie there in our own mess till someone lifts us out of it and bothers to change our pants.

They, animals, need no manual, they just know things. Compared to other primates, humans are born far too early for their brain to be mature, if we could stay in our mother’s womb for the brain to fully develop we’d be in there 24 months. The only reason we come out at nine months is because our heads wouldn’t fit through the birth canal if we stayed in there and would end up doing some serious damage to Mommy; she would probably never walk again and sue us for personal injury. You know that scene in Ben Hur where they tie each of a man’s legs to an elephant and then scream, ‘Giddy up’? That’s how Mommy would feel.

The genes build the scaffolding of your head invitro but once outside Baby only has his basic amphibian brain, just enough to keep his heart and breathing going and that’s about all. But it’s not all bad news, evolution can be smart sometimes and because we come out so undercooked the development of our brain depends on external experience. We have so much to learn once we’re out so we need that external stimuli to develop, which is a blessing because it would be impossible to learn shorthand or ping pong while we’re inside the womb.

This is a very clever idea because no one knows where you’re going to be born and you need different skills depending on the area and culture you plop out into. If you’re born in the Sahara, it would be good to have a structure that would make you proficient in camel straddling or if you’re born in New York, it’s more helpful if you develop the motor skills to honk and scream at other drivers. We have so much learning to do. This is called neural Darwinism.

By age three, the baby’s brain has formed about 1000 trillion synaptic connections.

At that point, the baby has the equipment to speak any language in the world. Its ears, tongue and mouth are primed for any sound or accent that may be needed depending on where it’s born. The sounds around you shape your tongue and palate, so the first 16 months will determine your accent. If you are Chinese, you will probably leave out ‘r’s for the rest of your life. ‘I’m sowwy but it’s twoo’. If you’re German, you will probably make that sound in your throat that sounds like you’re about to bring up phlegm.

Before you learn to speak, your brain is like a wad of chewing gum so any language is possible to learn with the perfect accompanying accent and, unless you become an impressionist, you’ll be stuck with it.

You better learn fast at this point because after the first two months half your neurons drop dead.

The right hemisphere has a higher rate of growth during the first 18 months, which establish the basic structures of attachment and emotional regulation. During the second year of life, a growth spurt happens in the left hemisphere. We learn to crawl, then walk and then there’s an explosion of language skills such as saying ‘poo, poo’. The hands and eyes become more connected to visual stimuli and vocabulary develops, so now we can demand things like a rattle on ice with a splash of vermouth. The language areas are activated by about 18 months after birth and babies begin to develop selfconsciousness where they can recognize themselves in a mirror.

This is the birth of the concept of ‘I’ when you get that feeling that you are you, if you know what I mean.

As Baby matures, neural circuits guided by the environment, connect. As sensory systems develop, they provide increasingly precise input to shape neural network formation and more and more complex patterns of behaviour. Now Baby can draw like Rembrandt. Movements and emotional networks connect with motor systems so you can spit in someone’s face because they have pissed you off.

Now all the wires of behaviour, movement, sensory experience and emotions connect and feed each other information, like wires in a complex phone system. Right and left hemisphere integration allows us to put feelings into words. This linking up of right and left hemispheres is accomplished through Mommy and Baby eye contact, facial expressions and speaking ‘goo goo’ which is called ‘motherese’. (Some lesbians use it with their cats.) The baby imitates Mommy and so she/he learns how to put feelings into words. Then when Mommy rocks the baby, her hormones are released making baby feel safe. A game of peekaboo activates the baby’s nervous system by the fine art of surprise and leads to cascades of biological processes enhancing Baby’s excitement. Peek-a-boo is not just an aimless activity, it is a brain grower. So forget chess and suduko, just jump out at someone from behind a door, you’ll be doing them a big favour, upping their IQ by thousands.

The memory of how Mommy is with Baby influences the baby’s physiology, biology, neurology and psychology. How the brain grows is affected by how she put you down, held, smiled, ignored or forgot you; she is the uber-regulator, the big boss of brain development. The neural clusters for social and emotional learning are sculpted by Mommy’s attunement with Baby.

She grows these neurons in the baby by making direct eye contact with her left eye to Baby’s right eye. This is why Mommies usually hold babies in their left arm so this eye contact is made easier.

When they gaze into each others’ eyes, their hearts, brains and minds are linking up. These face-to-face interactions increase oxygen consumption and energy. Also holding the baby in this position means it can hear Mommy’s heartbeat. Seeing her loving face looking down on Baby triggers high levels of endogenous opiates so he experiences pleasure in later social interactions by the positive and exciting stimulation from Mommy.

If the mother is too connected, this affects Baby and later he might feel people are encroaching on his space. If, on the other hand, she is too disconnected, he might in later life feel abandoned and become a comedian looking for constant attention. If the mother soothes the terrified baby, he learns to regulate his own fear. The mother’s face shows him what is safe and what isn’t. If she shows fear or any negative state, the baby internalizes it. If she expresses depression or shows an expressionless face, the baby, not being able to think something is wrong with the mother, believes he is the cause and so has a greater chance of having depression or some other mental dysfunction himself, while keeping an idealized image of his caretaker; his survival depends on her.

Babies are built to engage and respond to the world. If they don’t get a response, they stop engaging with the world and can become emotionally frozen.

The holding and separating which are repeated by mother and child, help baby to self-regulate throughout his life while he learns how to care for himself. When the mother over-holds you can soon see the results; every Jewish boy’s first novel is about mothers who never let go.


It was thought about ten years ago that, genewise, you’re hard-wired from birth; imprisoned by your DNA. But now science has broken that shackle; change is possible well into old age. It was thanks to a scientist named Michael Meaney that the idea of genetic determinism was toppled like the Berlin Wall; here one day, gone the next. His experiments on rats showed that the way a mother treats her babies determines which genes in the offspring’s brains are turned on and which are turned off, demonstrating that the genes we’re born with are simply nature’s opening shot. The genes that make you shy, resilient, anxious, exuberant are shaped by maternal behaviour. If maternal behaviour changes, the genes change. Fearful baby rats were put with nurturing mother rats and were licked rather than ignored and their actual genetic expression changed, proving we’re not held captive by our genes.

I wouldn’t have wanted my mother to lick me but perhaps it would have made me more positive and loving. Who am I to say?

But the point is that the brain changes continuously by every sight, sound, taste, touch, thought, feeling etc. Experience and learning remodel new circuits, neurogenesis.

We do know some of our ingredients and what they do and maybe in years to come we’ll be able to carry around some kind of recipe where we can change who we are day by day. We might decide we want to take a tablespoon of oxytocin and dribble in some dopamine to make us feel good about finishing our homework.

But for right now, the practice of mindfulness gives you some of the utensils that help you turn something you burnt and destroyed into something that tastes good and feels soothing inside.

How misguided we are in insisting the external world is exactly as we see it. Much of what you see out there is manufactured by your brain, painted in like computer generated graphics in a movie; only a very small part of the inputs to your occipital lobe comes directly from the external world, the rest comes from internal memory stores and other processes.

Think of the area in your visual cortex, a projection room creating what’s out there from incoming information. In actuality we see the world in single snapshots and it is a part of your brain that makes it seem like it’s constantly moving. There are about 70 separate areas working to create a cohesive picture of the world; one part contributes colour, another movement, another edges, another picks up shapes and another shadows. There is no single part that gets the whole picture. And in completely different zones, the images get a name, or an association or an emotional tag.

We live in a virtual reality. Think of The Wizard of OZ, you’re being run by the guy behind the curtain. You get clips that randomly come into your consciousness, never the whole film. So while you’re getting these fleeting clips to make you feel that’s all that’s going on, a trillion things without you knowing it are going on right now inside of you.

When you wake up in the morning, you remember who you were the day before because of billions of neurons, electrically zapping around the brain, working around the clock to make you believe you have unity and keep you wanting to exist.

Another thing your remarkable brain is doing is keeping your heart beating more than 100,000 times per day, that’s 40 million heartbeats per year, pumping two gallons of blood per minute, through a system of vascular channels about 60,000 miles in length or twice the circumference of the Earth.

Just now 100,000 chemical reactions took place in every single one of your cells. Multiply 100,000 chemical reactions by the 70 to 100 trillion cells that make up you. (I couldn’t do that but maybe you can.) So while your bodies doing its ‘thing’ you could be using your mind to bring you calm and happiness. What a segue to introduce you to mindfulness.


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