To follow up on our recent findings showing degeneration of the corticostriatal WMTs at advanced PD [28], we immunoreacted paraffin-embedded brain sections containing the caudate from early PD (unified stages IIa and IIb [27]; n = 3), advanced PD (Braak stages 5–6 [26], n = 3) and control (n = 3) cases with anti-SMI-32, a marker of glutamatergic corticostriatal connections [38] or anti-MBP antibodies. Here, MBP is linked to Parkinson disease.