Smorgasbord Health Column – Top to Toe – The Brain – How the brain develops from conception through life by Sally Cronin

It is two years since I posted this series on the major organs of the body and how they work and I am always looking for research updates to share with you. Dementia, Alzheimer’s Disease and other related conditions are rarely out of the headlines and it is probably everyone’s worst fear. There is a genetic link to some forms of dementia,but it is not as common as lifestyle related deterioration of the brain.  Even though we are living longer, dementia is not an automatic progression and understanding how this amazing organ works and what it requires to be health, is vital.

Part One: Brain – Introduction and Anatomy

How the brain develops from conception through life

How the brain develops.

We are hard wired and from the moment of conception there will be enforced changes to the structure and function of our brains. Whilst the process of development is beyond our control, there is still a powerful external influence on how well that programming is carried out. Before birth the health, nutrition, environment and lifestyle choices of the mother can impact both the rate of brain development and the health of the brain cells. After birth during the formative years up to age 15, environment, nutrition and stimulation of those brain cells is critical and if they do not receive sufficient amounts of all of these there is a chance that irreversible damage will occur.

The development of the brain does not follow a straight upward line it comes in waves with certain parts of the brain achieving full function at different times. There is however a sequence that every brain will follow.

At conception the sperm and the egg form a single cell combining to form the genetic blueprint. Over 60% of our genes are committed to forming our brain which is after all the control centre for all our other functions. Around three to four weeks into development a thin layer of cells form in the embryo, which then fold and fuse to form a liquid filled tube. This minute start is vital as it is the first stage in the development of the brain and spinal cord. This is followed by the production of nerve cells called neurons.

A miracle occurs as cells in the neural tube accelerate at an amazing rate reaching around 15million neurons an hour. This rate of growth continues for the first six months of a foetus’s development.

At around 14 weeks with millions of cells in place a change occurs as they begin to migrate to specific parts of the neural network and the inbuilt GPS usually sends them to the correct address. Some do however get lost or damaged in transit and die off.

Rarely however, some do reach the wrong destination and form incorrect connections and this coding error can lead to certain disorders such as autism or epilepsy, slower physical and mental development and in some cases more severe mental health issues.

At 20 weeks about half the existing cells are shed and those that remain are organised into compartments within the brain that govern virtually every automatic function in our bodies and also our senses and skills.

At birth we have around 100 billion brain cells and we begin the next stage in our development. Most of the connections between the neurons are barely formed and will need to be strengthened by the time we reach the age of three.

A baby has most of the senses working at birth such as sight, smell, hearing and the ability to respond to touch. Immediately with that first breath the brain kicks into overdrive and forms trillions of connections and pathways enabling learning.

As with the early development of the brain, it is vital that the environment, nutrition and stimulation are available to enable the brain to process and learn from experience.
These experiences trigger the electrical activity necessary to enable the brain to develop connections and grow. These connections are called synapses. The connections are formed by each neuron putting out a long tentacle like fibre called an axon. The neuron uses the axon to send messages to other neurons. The messages are sent as electrical signals and picked up by thousands of short, hair like fibres called dendrites (also produced by the neurons). Each neuron is able to connect up with thousands of other neurons.

It is then that ‘practice makes perfect’ comes into play as repeated experiences, sights, smells or movements form well-worn paths within the brain that we remember for a lifetime. By age two our brains have developed trillions of these pathways and although they continue to form throughout our lifetime they have reached their highest density.

Our higher functioning ability is usually operational by age three and we begin to think for ourselves, use language effectively and have developed personality traits.

After three years old we continue to absorb knowledge and experience like a sponge and the constant practice etches the functions into the brain. If that absorption ceases for some reason and we stop practicing certain functions, we can lose them completely as the brain discards little used pathways in favour of more travelled routes.

This pruning process and strengthening of the connections in the brain is most active in the teen years. The prefrontal cortex is the last to mature and it involves the control of impulses and decision-making. Anyone who has had children going through this phase will have a clear understanding of the ‘challenges’ that arise during this phase! This powerful surge in the brain is accompanied by the added influx of hormones which results in a chemical and electrical ‘perfect storm’.

There is a strong element of voluntary change at this stage of the development of the brain. It is around this age that we start making choices about what we eat, the amount of exercise we take, to take up smoking or drinking alcohol and to stop formal education. All these elements will affect the few years left of brain development we have left and therefore our mental capacity.

The brain continues to defrag the mainframe and the strongest connections survive. By our early 20s our brain development is matured into a powerful and functioning organ with approximately 500 trillion pathways.

At around 30 years old the physical changes will wind down in the brain and this is where even more of a voluntary contribution to growth, experience and maintenance is required to keep the pathways clear of debris such as plaque so that they continue to function efficiently.

This phase lasts for the next 35 or 40 years. The brain cells are active and we contribute to their health by diet, stimulation and avoiding lifestyle choices that kill them off. Such as smoking, drinking too much alcohol, not taking exercise, eating a diet rich in components that block our arteries and blood flow to the brain……you get the idea.

After 65 years old there is a natural dying off of cells in certain parts of the brain. This does not mean that you will lose all your mental capacity, but little things will begin to make an impact on your daily functioning. For example brain cells lost from the Hippocampus where we process memories will result in forgetfulness.

You are NOT destined to develop full blown dementia and you can make sure that you support your brain function by eating a healthy balanced diet, getting plenty of oxygen and regular exercise, reducing stress and interacting with others and events to stimulate the pathways to remain open. More so than at any other time in the lifespan of your brain, the voluntary choices and changes you make to your way of life will bring huge benefits.

©Sally Cronin Just Food for Health 1998 – 2019

My nutritional background

I am a qualified nutritional therapist with twenty years experience working with clients in Ireland and the UK as well as being a health consultant on radio in Spain. Although I write a lot of fiction, I actually wrote my first two books on health, the first one, Size Matters, a weight loss programme 20 years ago, based on my own weight loss of 154lbs. My first clinic was in Ireland, the Cronin Diet Advisory Centre and my second book, Just Food for Health was written as my client’s workbook. Since then I have written a men’s health manual, and anti-aging programme, articles for magazines and posts here on Smorgasbord.

If you would like to browse by health books and fiction you can find them here: https://smorgasbordinvitation.wordpress.com/my-books-and-reviews-2019/

Next time a more detailed look at dementia and recent research and how we can take preventative action at any age to minimise the decline in brain function.