What role does myelin play in high cognitive functions?

Myelin plays a crucial role in enhancing the speed of electrical signals along neurons. This is particularly important for high cognitive functions, as myelination allows for the rapid transmission of action potentials between nerve cells. When axons are myelinated, the electrical impulses can jump from one node of Ranvier (the gaps in the myelin sheath) to another, a process known as saltatory conduction. This significantly increases the conduction velocity compared to unmyelinated fibers, facilitating faster and more efficient communication between different parts of the brain.

The enhanced speed of electrical signals is vital for coordinating complex processes involved in cognition, such as reasoning, decision-making, and problem-solving, which require quick information processing. Thus, the structural role of myelin in insulating and supporting axons contributes significantly to the efficiency of neural networks that underpin higher-level cognitive functions.