MAPT and Alzheimer disease: Tau biomarkers in CSF, notably t-tau and p-tau, are prognostic and diagnostic for AD, which is characterized by neurofibrillary tangles.42 Recently, tau positron emission tomography has evolved for clinical diagnosis of AD and differentiates from other neurodegenerative tauopathies.43 P-tau231 may be the preferred CSF discriminatory tau protein for an AD diagnosis.43,44 We observed 1 association of p-tau231 with motor performance.