Brain Development
What is described below is a simplified account of a complicated process which is still being studied. Attempts have been made to explain this in an understandable way that is not misleading or misrepresentative. Any comments darren@newlandchiropractic.co.uk">welcome.
First generation neuron growth - Apoptosis
Soon after conception millions of neurons multiply and start growing. At this stage they are immature; they are like young trees with a few branches (called dendrites). The trunk is the axon which is what the electrical signals pass along.
Dendrites grow towards other neuron's axons and connect with a synapse. Synapses allow the neurons to send and receive signals to each other.
When a neuron receives a signal it is stimulated to grow more dendrites and thereby able to make even more connections with other nerves.
The more the neurons are stimulated the stronger the dendrite branches become and signals pass along the neural network with increasing ease.
This is why practice makes a new task easier. With stimulation dendrites grow to pass the new signals associated with the task across the network. Children learn in this way, adults do too but it usually takes them longer.
Not all the neurons in a baby’s brain make connections; the unconnected ones die through lack of stimulation. This type of cell death is called Apoptosis, and is part of normal brain development. The stronger neurons create synapses and survive. The percentage of nerves lost through apoptosis varies; we think it depends on both genetics (nature) and the environment (nurture).
Second generation nerve growth
This occurs 3-4 months after birth and the only neurons that develop during this time are the VECs. As they develop VECs synapse with many first generation nerves and have a controlling effect over them.VECs develop in four particular regions of the human brain involved in:
• Fine motor control and complex hand movements like writing, painting and using tools
• Focus, concentration and problem solving
• Memory (short term or working memory and probably long term memory too)
• Organising, anticipating / thinking ahead and planning skills
• Motivation and understanding long term gains
• Recognising and controlling emotions / behaviour
• Socialising, empathising and controlling emotions
• Understanding and using language
Children with learning disabilities or Developmental Delay often have problems with these particular areas.
Intelligence and these new, second generation of brain cells are seperate. The first generation of nerve cells that develop while you are in the womb give you the potential for intelligence. The second ave of brain cells that develop at four months of age give you the ability to concentrate on what you are doing.
Why might VECs not develop?
VECs seem more vulnerable than other neurons, probably because:
• They do not develop in the womb and are more "exposed" to trauma and toxins
• They seem to be the most recent neurons to evolve and are probably less adaptable to trauma or toxins.
Neurotrophins pave a chemical pathway for VECs to follow, long before they develop. Problems with the baby’s or mother’s health during pregnancy or birth may affect the neurotrophins and hinder VEC development.
Genes also play a part; different genes seem to help neurotrophins and the development of VECs.
Studies conducted so far by the Tinsley House Treatment Centres have found Developmental Delay is significantly more likely if:
• During the birth there was foetal distress (low APGAR score) and/or birth interventions e.g. emergency caesareans or assisted delivery with ventouse or forceps,
• Genetic predisposition, 72% of parents of children attending Tinsley House admitted to having learning / behavioural problems.
Interestingly VEC's have only been found in the brains of humans, African Apes and whales. It would seem these are the only mammals in which bpoptosis happens.
African apes only have a few hundred VECs; they develop while the baby is in the womb. Humans may have about one hundred thousand spindle cells. It is likely that these relatively few cells (compared to the millions in our brain) are responsible for much of our “human” behaviour. One study found a 60% reduction in the number of VECs in patients with dementia.
