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Baby Brain Development 101

Updated: Sep 30, 2019

Brain development is an intricate process that takes decades to mature. It includes all of a child’s present and future capacities, their intellectual abilities and their emotional and psychological habits, abilities and mindsets that will enable them to negotiate life.


One of the best things one can do to protect a baby’s growing brain is to allow a pregnancy to run its full course whenever possible.

Babies are born with a set of ‘survival’, primitive or neonatal reflexes which are involuntary movements; their job is to assist during those early months. The sucking and rooting reflexes help with breastfeeding/nursing for instance.

Later on these survival patterns are ‘controlled’, inhibited or integrated to make space for more mature responses and to allow for higher learning (e.g. ensuring that the body remains upright and aligned*, healthy motor development which is the ability to move around and manipulate our environment, developing of cognitive processes such as attention and reasoning etc).

The primitive reflexes usually integrate by three to four months of age, though it may last up to six months. It is essential for reflexes to integrate but sometimes they don't (some adults may have retained primitive reflexes**).

Retention of primitive reflexes can be caused by a variety of factors. The birth process is a key factor. Therefore a traumatic birth experience or birth by c-section may lead to retained reflexes.  Additional causes can include: falls, delayed or skipped ‘creeping’ or crawling and chronic ear infections .

This does not mean that all premature births, for example, result in retained reflexes & it does not suggest that normal or 'easy' births can not result in retained reflexes. There are many complex variables.

It's important to note that retained reflexes can be remedied by a chiropractor.


Genes provide a ‘map’ for brain development but the field of epigenetics - which in very simple terms, means ‘above’ or ‘on top of’ genetics - has now provided evidence that genes are simply a starting point not our destiny.

In other words, while the sequence of DNA may not be affected, the way genes work - called gene expression can. Environment (e.g. thoughts, emotions, food, exposure to toxins etc) signals our genes and turns them ‘on’ or off’ so to speak.

There are critical, sensitive periods, or ‘prime times’ that genetic processes are being ‘turned on’ for various aspects of brain development. For example, language development depends on adequate hearing and if hearing loss is not diagnosed at an early age and the brain cannot receive the sounds that lead to language development, the language parts of the brain begin to ‘close up’.

During early childhood (0-7 years of age) children’s brains are at their most ‘malleable’ and more sensitive, than at any other point, to influences from the surrounding environment. At around three years of age a child has around 1000 trillion brain connections or synapses.

To put this into perspective, during adolescence brain connections will be around 500 trillion; this number remains relatively stable into adulthood.


Children are born with a lower brain that is much more developed and powerful than their upper brain.

The lower brain governs our strong emotions, is reactive and it’s what informs our ‘fight’ or ‘flight’ responses when we feel threatened.

This is one reason why children might do things such as throw their food on the floor or scream when they do not get what they want.

A parent who is not aware of their child’s developing brain not only expects too much from them, but could also cause significant damage. For instance, by altering the brain with the use of physical punishment such as spanking or isolation such as ‘time out’.

By damage I mean not only in the ‘I'm traumatised’ kind of way but also in the 'I literally have less grey matter in my brain" kind of way.

Dr. Daniel Siegel, clinical professor of psychiatry at the UCLA School of Medicine and executive director of the Mindsight Institute, explains that when we spank a child, we are inflicting pain. The child’s ‘lower brain’ is programmed to avoid pain, as pain is perceived as threat.

However, the child’s lower brain is also responsible for the instinct that draws them to seek comfort from their parents (or primary caregiver). Their brains become confused, as they are simultaneously pushed away from the source of the pain and yet pulled toward their biological source of comfort.

This confusion causes the brain to produce the stress hormone cortisol.

When children experience stress on a regular basis, the body becomes overloaded and sends signals to the nervous system to maintain constant vigilance and ‘prepare for a lifetime of trouble’.

Now, I’m not suggesting we ‘allow’ kids to throw food whenever they like and kick and punch others when they are frustrated in the name of brain development.

No! But when we know what is actually happening in their brain, we can:

1. Be more understanding and compassionate

(‘I can see you really didn’t like me saying ‘no’ to you’)

2. Help our child develop healthier ways, by modelling, how to deal with frustration/anger/disappointment/ fill in the blank

(‘I am going to put away your food for now, when you feel calmer, you may continue. Would you like a hug? Let’s take a few deep breaths together’).

3. Recognise our children are not behaving 'this way' to make our life miserable. By having knowledge and information, we as parents may find it easier to not get triggered by our child's behaviour and better yet, to not take their behaviour personally. Because it is not.


The release of high levels of cortisol, especially in early childhood:

- kills brain connections,

- is toxic to the brain and inhibits healthy growth,

- it hinders the development of a child’s prefrontal cortex, the part of the brain that controls our intellectual functions (which include working memory, self-regulation, and cognitive flexibility - this flexibility allows our child to handle abstract concepts). These functions underpin abilities like resilience and perseverance.

- on an emotional level, chronic early stress or toxic stress - can make it difficult for children to moderate their responses to disappointments and small setbacks can feel devastating. (Some universities have introduced programs to help students deal with failure. But let's not wait till our kids are 18+)

- it also changes gene expression which makes our kids less capable of thinking imaginatively.


It is said that children will flourish regardless of their circumstances and that their neural development relies on experiences that are easily available to almost any child.

While it is understood that the brain may very well 'raise itself' there are certain environmental factors that either produce healthy or unhealthy levels of stress (stress of course, has its benefits too) as we've discussed, and those stressors either support or undermine healthy development:

- Physiological development (compromised immune system, metabolic shifts that contribute to weight gain, and, later in life, a variety of physical ailments, from asthma to heart disease) and

- Psychological, mental and emotional development

In other words, everything is connected and while parents could potentially ‘simply sit back and watch their child’s brain develop’ let us remember that:

- the optimal home environment,

- the quality of our child’s earliest environments,

- access to important, positive, wise people in their lives (in the early years: educated parents and caregivers - by this I mean, educated about parenting)

- the availability of appropriate experiences at the right stages of development...

Are crucial to brain development.

All experiences lead to changes in the architecture of the brain, so when making decisions we need to take into consideration this ‘neuroplasticity’ - the ability of the brain to continuously change throughout life - so our children can take advantage and make the most of their environments and opportunities.


As parents this takes the form of asking ourselves lots of questions, for example:

- Do we feel comfortable and OK with our children watching certain TV programs/movies or playing violent video games and spending hours in front of a screen?

- If the analytical part of my child’s brain develops after age 7, what am I modelling in the first 6 years of my baby’s life?

- What are they listening to? What messages, what's going 'in' unfiltered?

Each stage of our child's growth will look different. These are some of the things my husband and I did at home to support our boys' healthy brain development:

- As babies we encouraged independent, self-directed play,

- We read to them lots (in English and Spanish, morning and night

- We talked to them in first person ('I am making you a snack' instead of 'Mummy is making you a snack')

- We made eye-contact

-As toddlers we joined a playgroup that values imagination and play-based activities and stories versus academic instruction before the age of 5.

- Lots of outdoor play (from babies)

- As our children grew, we provided (and continue to provide) opportunities for our kids to engage in building relationships by:

*spending time with new and old friends & family (different genders, all ages),

*playing board games as a family,

*participating in sports that placed emphasis on fun rather than competition,

*group activities encouraging kids to work with others collaboratively, as a team,

*involving them in household chores from early on (e.g. packing up toys, making beds, helping with laundry, setting the table, emptying dishwasher without being paid for it)

*involving them in household matters from early on (e.g. family meetings)

*allowing them to be an active participant in their development from day 1

- At all stages, providing the gift of boredom has been gold.

- No screen time before 3 years of age (here are some tips on how to do it)

- Acknowledging feelings without trying 'to fix' things

-Encouraging change (new experiences, travel, changing seats around table, trying different foods - even if it only means licking the broccoli at first)

- Seeing a holistic chiropractor to support with retained reflexes

As adults, if we didn’t get what we needed as children, there are ways to reorganise our brain later in life. Some options include:



*Emotional intelligence (learning and practice),



*Cognitive behavioural therapy or CBT

Here's to healthy brain development from the start!

Suni xo

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Notes, Resources and Further Reading:

* Underdeveloped postural reflexes mean that balance and coordination will be poor. This not only has the obvious effect of lack of protection from falling but has wider implications for instance socially and in the school classroom.

** Adults may also have retained primitive reflexes. Symptoms include:

Anxiety, Agoraphobia, Panic attacks, Poor self esteem, Excessive shyness, Overreaction to incidents, Inability to cope with change etc

Epigenetics: Definition & Examples

A note on yelling:

While yelling is not recommended either, our kids are not going to be damaged by our occasional bad moods, but exposing children to harsh corporal punishment (HCP) may have detrimental effects on trajectories of brain development.

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