Inclusion Criteria:  Subject presenting a mild cognitive disorder of the amnesic type, defined by a memory complaint, a Mini Mental State ≥ 24 and a score ≤26 on free recall or ≤45 / 48 on total recall) of the RLRI16 episodic verbal memory test At least 7 years of schooling  Exclusion Criteria:  Severe psychiatric pathology Known neurological pathology High risk of apnea syndrome defined by at least 2 positive categories (each with a score ≥2) on the Berlin Questionnaire for Apnea Syndrome Screening High risk of behavioral disorder in REM sleep defined by an RBDSQ score> 5. Taking sleeping pills or antidepressants Severe heart disease or unbalanced diabetes