Clinical Research Directory

Inclusion Criteria common to all participants: * Age\> 50 years at the inclusion * Patient with regular sleep patterns * Patient having given written consent * Patient affiliated to a social security regimen Inclusion criteria for subjects with Alzheimer's disease: * Patient with a beginning Alzheimer's disease defined according to the criteria of the National Institute on Aging-Alzheimer's Association or carriers of a prodromal Alzheimer's disease defined according to the criteria of the International Working Group IWG-2; the diagnosis must be supported by brain imaging and a blood test carried out in routine care * MMSE score ≥ 24 Inclusion criteria for healthy volunteers: * Absence of neurodegenerative pathologies * Matched in age (+/- 5 years) and in sex with a patient Non-inclusion criteria common to all participants: * Psychiatric pathologies (except depression or anxiety disorders stabilized for more than 3 months) * History of pathology which may have consequences on cognitive functioning and / or sleep: brain tumor, constituted stroke, epilepsy, head trauma (with clinical or parenchymal sequelae objectified on brain imagery), brain surgery * Any significant comorbidity likely to constitute a confounding factor according to the clinician * Psychotropic treatments introduced or modified \<3 months before inclusion * Hypnotic and / or sedative treatments * Chronic consumption of alcohol or drugs * Legal incapacity and / or other circumstance rendering the patient unable to understand the nature, objective or consequences of the study * Major under guardianship or curatorship * Patient not French-speaking by birth or illiterate Exclusion Criteria common to all participants: * Sleep disorders defined by a score\> 5 on the Pittsburg sleep quality index (PSQI) * A score\> 10 on the Epworth sleepiness index