Definition: Myelination is the process by which a fatty layer, called myelin, accumulates around nerve cells (neurons). Myelin particularly forms around the long shaft, or axon, of neurons. Myelination enables nerve cells to transmit information faster and allows for more complex brain processes. Thus, the process is vitally important to healthy central nervous system functioning.
Myelination begins in infancy and continues into adulthood.
During the tween years, myelination is particularly occurring in the frontal lobe of the brain - the section of the brain that begins just behind the forehead. Myelination of the frontal lobe aids tweens' cognitive development. In particular, it enables them to have better "executive functioning," which includes planning, reasoning and decision making skills. It also helps tweens inhibit their impulses more efficiently and to demonstrate greater self-discipline.
Related terms: myelin, executive functioning, neuron
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