Although clinical criteria ultimately determine the pathological diagnosis of Alzheimer’s disease, ‘Alzheimer’s’ is also an ordinary sign, falling within a range of other possible signs, values and beliefs that define and are used to interpret dementia and mental diseases. While looking at talk-in-interaction in which two people diagnosed with Alzheimer’s interact with other people, this article tries to show that the way in which both lay and professional people interpret Alzheimer’s signs allows us to shed some light upon the core of the traditional and controversial dichotomy between normal and pathological. The interactions analyzed in this paper show how people oppose biomedical discourse, suggesting that other forms of interpreting aging and forgetfulness are possible. It has opened multiple cartographies or varied spheres of communicability influenced by the signs of Alzheimer’s.