Modafinil is a wakefulness-promoting agent approved to improve wakefulness in adults who experience excessive sleepiness due to obstructive sleep apnea or shift work sleep disorder. It is used off-label in MS to treat fatigue and sleepiness.
Myelin is a fatty white substance that surrounds the axon dielectric (electrically insulating) material that forms a layer, the myelin sheath, usually around only the axon of a neuron. It is essential for the proper functioning of the nervous system.It is an outgrowth of a type of glial cell.The production of the myelin sheath is called myelination. In humans, myelination begins in the 14th week of fetal development, although little myelin exists in the brain at the time of birth.t is essential for the proper functioning of the nervous system. It is an outgrowth of a type of glial cell. The production of the myelin sheath is called myelination. In humans, myelination begins in the 14th week of fetal development, although little myelin exists in the brain at the time of birth.
The myelin sheath is a covering of the neuron (nerve cell) made by schwann cells wrapping themselves around the neuron down the length of the axon.he main purpose of the myelin sheath is to speed up the conduction velocity of nerve impulses. While there is an electrical charge involved in signals along nerves, it's not the same as a current along a wire. Instead, small channels in the membrane of the neruon open up, and ions flood through.