Inclusion Criteria:  Healthy Volunteers  aged 18 to 40 years old and aged 60 to 80 years old native French speaker right-handed with a level of education greater than or equal to the Certificate of Primary Education free of any medical or psychiatric condition that may interfere with cognition  Neurological patients  patients with mild neurocognitive impairment due to Alzheimer's disease patients with semantic dementia syndrome right-handed patients with a right or left unilateral surgical lesion of the anterior temporal lobe as a result of pharmaco resistant temporal epilepsy, with no seizures in the last 6 months, with a memory quotient greater than 75, and free of internal extra temporal lesions on MRI patients with autoimmune limbic encephalitis who have been seizure-free for one month 1 KA patient, suffering from the rare syndrome of developmental amnesia  Exclusion Criteria:  All participants  MRI contraindications sensory deficit interfering with experimental tests protected major (safeguard justice, trusteeship and guardianship) and persons deprived of liberty  Healthy volunteers  - deficit score on the MoCA scale according to current calibrations  Neurologic patients  7-items modified Hachinski ischemic score >2 dementia epileptic seizure in the month prior to inclusion for epileptic patients undergoing surgery and limbic encephalitis patients