Alzheimer’s disease (AD) is a global epidemic, affecting an estimated 130 million people worldwide by 2050, and leading to costs of around US$70 billion a year. This detrimental disease has currently no cure after onset but recent evidence shows that early detection measures may lower AD risk. Therefore, approaches that can detect AD before symptoms arise are of fundamental importance because such a preclinical stage offers a critical window of opportunity to capture the pathophysiological processes as early as possible potentially preventing neuronal degeneration and progression. In order to fill this gap our long-term goal is to develop a non-invasive, sensitive and robust biomarker that can be deployed in large amounts at low-cost, both in developed and rural countries. To do so, we established portable technology (EAR-DREAM) that allows for long-term, non-obtrusive recordings of brain signals from the ear. In this project we will use this technology in the largest known population of autosomal dominant AD (ADAD) in the world, where mutation carriers have a 100% chance of developing AD. This provides a unique opportunity to test promising biomarker candidates in asymptomatic individuals. We will record brain signals during wake and sleep, and during cognitive states, known to be affected in individuals with AD. In a first step, we will collect large sample data acquired from mutation (asymptomatic) and non-mutation carriers in ADAD populations against data acquired in selected control populations in Switzerland. Thereafter, we will identify, via state of the art predictive models, a robust and integral biomarker of AD risk from the collected data. Thus, this study will allow for the first time the promising possibility to develop an early life span, low-cost, non-invasive AD biomarker validated independent of culture and socioeconomic status.