“Neurons that fire together, wire together”

'How we learn

Neural networks and neuroplasticity

The human infant is born with approximately 100 billion brain cells, or neurons.

That number remains relatively stable throughout life, a fact that has contributed

to the long-held belief that the brain is fixed, or hard-wired, particularly post adolescence.

However, what is far from formed at birth and continues and changes

throughout life, are the tens of thousands of connections that form between each

one of these 100 billion neurons. The creation of these connections form neural

networks and their continual restructuring and change is known as neuroplasticity.

A neuron is a single cell, with a cell body, or soma, that houses the DNA and

proteins that guide its functioning. Each neuron has one axon that sends

messages and many thousands of dendrites that receive messages. Dendrites

appear like the branches of a tree, with more branches representative of more

connections. These connections represent learning.

On its own, a single neuron can achieve nothing - it takes many thousands

combined to generate every action, thought or memory we have. Neurons,

therefore, need to relate to other neurons. They achieve this by sending electrical

signals along their axon, which, upon reaching a threshold, release neuro chemicals

into the gap, or synapse, between two neurons. If the dendrites of

the receiving neuron have the appropriate chemical receptors, a connection will

be formed that results in the receiving neuron firing its own electrical charge,

which will be received by yet another neuron and, so, on goes the flow. One of

the founders of modern neuroscience, Donald Hebb, showed that neurons that

continued to activate one another in this way strengthened their connections, like

a path through a forest. “Neurons that fire together, wire together” became Hebb’s

Law and is a fundamental principle to how we learn 1.

In this way, our brains develop neural networks that embed and store our learning.

You have neural networks for every conceivable object, person, animal and

situation you have ever encountered. The neural network for your perception of

an orange will involve cells in different areas of your brain that code for the type,

shape, feel, size, smell and taste of an orange, along with whether or not you like

oranges, when and where you last had one, ways to use them, as well as abstract

variants, like the colour orange. It takes thousands of connected neurons in a

neural network for ‘orange’ to create this representation each time you see, think

about or just hear the word, ‘orange’. And that’s just an orange.

Your perceptions change over time. You acquire new information that adds to or

changes what you know about things and people in your world, or how you feel

about them. For example, a colleague may, surprisingly, disappoint you in their

response to an issue and this gives you a new insight into their motivation or

agenda. This new information requires your own neural network of this colleague

to change - literally, physiologically change - in order for you to process it. This

change shows the plasticity, or adaptability, of your neural connections and occurs

thousands of times each day as you experience your world - at both conscious

and subconscious levels.

Source: PageUp People