The long axon that projects out of a neuron cell body is wrapped in a fatty coating called myelin sheathing. The coating is actually provided by specialized glial cells (oligodendrocytes) which help wrap up to 50 differernt axons, thus forming a link between axons. Additionally, many different glial cells help to provide the myelin sheathing for a single axon, in turn helping to connect the axon to other axons in multiple ways.
The integrity of the myelin sheathing is required for the formation of an action potential in the axon, boosting nerve transmission speed up to 30 fold. This is incredibly important for optimal brain function as extreme speed of transmission is needed to integrate all regions of the brain in a way that correlates to intelligence and human ability.
Furthermore, axons are now found to be talking to each other – even independent of a nerve transmission signal! It appears this may have to do with learning, wherein axons hold data and integrate it at a slower speed and then help dump it into your long-term memory at night. This is key to optimal learning.
Myelin sheathing is more than just a structural substance coating nerves. While it is true it needs to be understood and worked with in the context of problems like MS, it is equally true that its integrity is associated with human ability. Acetyl-l-carnitine is now shown to be one nutrient that can help in this regard.
- ^ Acetyl-L-Carnitine and Myelin Sheathing Gene Expression Mol Neurobiol. Traina G, Federighi G, Macchi M, Bernardi R, Durante M, Brunelli M.