myelinated 0.2: unmyelinated ≤0.8 µm
||Hildebrand C, Remahl S, Persson H, Bjartmar C. Myelinated nerve fibres in the CNS. Prog Neurobiol. 1993 Mar40(3):319-84 p.327 left column 2nd paragraphPubMed ID8441812
||P.327 left column 2nd paragraph: "Unmyelinated axons in CNS tracts have diameters up to 0.8µm. Since these axons lack glial ensheathments, they are directly exposed to the extraceIlular space. Interactions between adjacent axons may lead to subthreshold excitability changes (refs - link ). Myelinated CNS axons have diameters down to 0.2µm, but size spectra of myelinated and unmyelinated axons overlap considerably (Fig. 8, refs - link )."