| Comments |
"Conduction velocity increases with both axon diameter, and with myelination and, in the central nervous system, the great majority [of] axons that are > 0.3 microns in diameter are myelinated. The myelin sheath, produced by specialized glial cells, is a compacted spiral of membrane...At diameters of <~0.3 microns, Waxman and Bennett (1972, PMID 4506206) found the benefits of myelin to negligible (Figure 1), and few myelinated axons are found within the CNS at diameters below this value." |