WB confirmed the relative WM levels of the different neurofilaments (NFL > NFM > NFH) and showed no change in these levels between motor PD and controls (Fig. 2c1, c2), although on average the WM axons had increased NFL immunofluorescence in both early and late PD (Fig. 2b3, no difference between PD groups p = 0.55). Here, NEFL is linked to Parkinson disease.