THE SCIENCE BIT

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How The Brain Works:

Your brain is a thinking organ that learns and grows by interacting with the world through perception and action. Mental stimulation improves brain function and actually protects against cognitive decline, as does physical exercise. The human brain is able to continually adapt and rewire itself. Even in old age, it can grow new neurons (which is good news for a lot of us!), creating New Neural Pathways.

The human brain has close to 100 billion nerve cells, called neurons. Each neuron is connected to thousands of others, creating a neural network that shuttles information in the form of stimuli, in and out of the brain constantly. Each neuron is made up of four main parts: The Synapses, Soma, Axon and Dendrites. The soma is the body of the cell where the information is processed. Each neuron has long, thin nerve fibres called dendrites that bring information in and even longer fibres called axons that send information away. The neuron receives information in the form of electrical signals from neighbouring neurons across one of thousands of synapses, small gaps that separate two neurons and act as input channels.

Once a neuron has received this charge, it triggers either a “go” signal that allows the message to be passed to the next neuron or a “stop” signal that prevents the message from being forwarded. When a person thinks of something, sees an image, or smells a scent, that mental process or sensory stimulus excites a neuron, which fires an electrical pulse that shoots out through the axons and fires across the synapse. If enough input is received at the same time, the neuron is activated to send out a signal to be picked up by the next neuron’s dendrites.

Most of the brain consists of the ”wiring’ between the neurons, which makes up one thousand trillion connections. If these fibres were real wire they would measure out to an estimated 63,140 miles inside the average skull! A healthy, well-functioning neuron can be directly linked to tens of thousands of other neurons, creating a totality of more than a hundred trillion connections – each capable of performing 200 calculations per second! This is the structural basis of our brain’s memory capacity and thinking ability. Each stimulus leads to a chain reaction of electrical impulses, and the brain is constantly firing and rewiring itself. When neurons repeatedly fire in a particular pattern, that pattern becomes a semi permanent feature of the brain. Learning comes when patterns are strengthened by repetition. As a product of its environment, our “three pound universe” is essentially an internal map that reflects our external world.

The Human Nervous System
There are 5 different types of synapses. We are interested in Non Channel Synapses – which have neuroceptors that are membrane-bound enzymes. When activated by the neurotransmitter, they catalyse the prodution of “messenger chemical” inside the cell, which can, in turn, affect many aspects of the cell’s metabolism. These synapses are involved in the slow & long lasting responses like learning & memory. Typical neurotransmitters are adrenaline, noradrenaline, dopamine, serotonin, endorphin, angiotensin & acetylcholine. The more you