Clinical Research Directory

For the positive amyloid load group: -Participants who meet the criteria of subjective cognitive decline or mild cognitive impairment (Clinical Dementia Rating \< 2; Mini-Mental State Examination ≥ 21) and brain amyloid-beta (Aβ) accumulation confirmed by CSF or amyloid-PET, the inclusion age range is 55-80 years. For healthy groups: -Inclusion age range is 18-80 years. Inclusion criteria: * Proficiency in the French language (close to native level) to complete the neuropsychological evaluation and cognitive tests. * MRI compatibility: absence of metallic materials in the body (implants, vascular clips, certain types of orthopedic material, etc.), a pacemaker or other types of stimulators, cochlear implants, or any other electronic devices. Exclusion criteria: * Current or past psychiatric or neurological conditions (except for those directly associated with the patient group). * The presence of severe untreated sleep disorders. * The presence of irregular sleep-wake cycles (due to shiftwork or extreme chronotype). * The presence of moderate depression or high levels of anxiety. * Ongoing treatment with psychotropic medications (benzodiazepines, antidepressants). * Regular or excessive consumption of alcohol or caffeinated drinks. * Consumption of other psychoactive substances known to have an impact on the central nervous system. * Insufficient visual or auditory acuity to complete the assessments if uncorrected. Normal hearing is required for sound stimulation to be effective. * Claustrophobia that prevents undergoing brain imaging (MRI). * Pregnancy or currently breastfeeding