MAPT and Alzheimer disease: In contrast to PSP cases, no tau pathology was evident in the PNS of AD or CTE cases: AD cases cranial nerves III (0/10: 0%), IX/X (0/5: 0%), XII (0/4: 0%), anterior spinal roots (0/5: 0%) and posterior spinal roots (0/5: 0%); CTE cases cranial nerves III (0/2: 0%), V (0/1: 0%), IX/X (0/2: 0%), XII (0/2: 0%), anterior spinal roots (0/3: 0%) and posterior spinal roots (0/3: 0%).