Rotation errors in path integration are associated with Alzheimer's disease tau pathology: a cross-sectional study.

Background: Early Alzheimer's disease diagnosis is crucial for preventive therapy development. Standard neuropsychological evaluation does not identify clinically normal individuals with brain amyloidosis, the first stage of the pathology, defined as preclinical Alzheimer's disease. Spatial navigation assessment, in particular path integration, appears promising to detect preclinical symptoms, as the medial temporal lobe plays a key role in navigation and is the first cortical region affected by tau pathology.