They make myelin, the fatty
coating around axons — long, threadlike fibers that relay neural impulses from one cell to the next, activating the circuitry that endows us with the physical and emotional capacity to fully embrace the world.
Each time a network is activated — the information recalled for review or use — the connections become stronger and faster (speed through a circuit is largely determined by the layers of myelin
coating that are built up
around the
axons — this is also in response to the flow of the electric current of information transport when the circuit is activated).