The brain is composed of billions of nerve cells or neurons that connect to each other in many complex ways. These connections form neuropathways or brain circuits that interact to give us learning abilities, memory, and abstract reasoning. The more interaction, the more complex the processes and outcomes are. This make us who and what we are – reasoning beings.
All nerve pathways work by the transmission of chemicals from one nerve cell to the next called neurotransmitters. The neurotransmitters stimulate the next cell that in turn stimulates the next until there is a chain reaction that grows exponentially and forms the circuit that results in a complex stimulation that we call a thought or reaction. The more often we use this pathway, the faster the transmission and the stronger the signal. Just as one may be clumsy when learning to hit a tennis ball, the more often you do it, the better you become and the less effort it takes until it becomes second nature. Trainers call this “muscle memory’ but it is really neuroplasticity at work. The nerves that control the muscles are enhanced and the behavior, in this case hitting a tennis ball, becomes an embedded process. Later, when mastering the game of tennis, you do not have to think about how to hit the ball while running or obtaining a return position. This is your neuropathway at work.
How these events occur and how neuropathways are formed have long eluded neuroscientist. We now believe we have an understanding of the changes that occur to allow this process to take place. When neurotransmitters are released, they are rapidly removed by the body making the effect fleeting – the blink of an eye or glance at traffic. However, the more often you utilize a specific neuropathway, the greater the amount a neurotransmitter released and the more sustained the reaction. Recent studies further suggest a physical change takes place with repeated use of a pathway. Insulating or mylenated cells begin to grow and surround the junctions between cells used repetitively. This prevents the dissipation of the neurotransmitters and enhances the rapidity and duration of stimulation of the neuropathway. This makes the enhancement of that circuit permanent. We all experience this when riding a bicycle after not doing so for many years. We may be rusty but can rapidly regain our competency with a little practice. Likewise, we all surprise ourselves when studying with our children and remember information like dividing fractions after many years.