When we think of the biological process of learning, the synapse often presents itself as the topic of conversation. The little space between neurons where neurotransmitters are released and transferred. The more two neurons communicate, the better they become at this process.
“The axon (the long output fiber) of a neuron is designed, down to the molecule, to propagate information with high fidelity across long separations, and when its electrical signal is transduced to a chemical one at the synapse (the junction between neurons), the physical format of the information changes while the information itself remains the same.”
—Steven Pinker, How the Mind Works
The Other Part of the Picture
When a neuron fires, a signal is sped along that neuron’s axon. The axon reaches out to other neurons, where they meet we’ll find synapses. When we talk of white and grey matter, the white is made up of axons, it is where information is transferred; the grey matter is made up of the cell bodies and is where information is processed.
While the synapse is essential, another process helps to ensure that the signal can travel along the often lengthy axon quickly and with little data-loss. Wrapped around the axon is a fatty substance known as myelin. It’s lubricant for axons.
“The sheaths of myelin, the fatty membrane that surrounds the axons, continue to mature well into childhood and even adolescence. Their main role is to provide electrical insulation and, as a result, increase the speed and fidelity with which neuronal discharges propagate to distant sites.”
—Stanislas Dehaene, Consciousness and the Brain
Myelin helps the electrical signal travel quickly along the axon, and helps prevent it from dissipating from the edges, which likely becomes more important as the required distance increases.
Myelin changes depending on the demands. Cells known as oligodendrocytes create and maintain myelin with their long arms, tasked with wrapping myelin around the axon when and where it’s necessary.
What Should We Do?
Myelin forms as a result of use. Subsequently, having an active mind and learning new things will help lace more myelin around your axons. Myelin degrades over time if it’s unused, but importantly, it can also be replaced if attention resurfaces. This is another type of plasticity, separate from the synapse-related process, but also essential to a well-maintained and ready-to-learn brain.
Start learning how to learn and keep your brain’s myelin healthy with Connecting the Dots.