Pathological aging (PA) is used to describe the brains of people which have Alzheimer’s disease (AD)-like pathology but where the person showed no signs of cognitive impairment whilst they were alive. New research shows that PA and AD brains contain similar amyloid β (Aβ) plaques and that while on average AD brains contain more Aβ there was considerable overlap in Aβ subtypes. These results suggest that PA may simply be an early stage of AD.