As COVID-19 pandemic is still ongoing, patients follow-up begins to reveal cognitive and psychological disorders. There are not yet well described, neither their physiopathology. This study will consist in the detection and characterization of cognitive and psychological impairments in young patients under 65 years of age who have been hospitalized more than 72 hours for a severe COVID-19 infection.

Initial consecutive screening of patients (<65 years) hospitalized between the 01/10/2020 and the 01/07/2021 for more than 72 hours for COVID-19 infection in 6 hospitals of the East of France. If detection of cognitive complaints (QPC scale : Questionnaire of cognitive complaints), continuation of the study.

Evaluation with cognitive assessments, morphological and functional imaging and EEG will be done at 9 ± 3 months and 2 years after initial hospitalisation. Data will be collected concerning social and professional outcome.

An ancillary study will be conducted at the Nancy University Hospital. This ancillary study is entitled "TRAUMA-COV: Screening and therapeutic proposal of post-traumatic sequelae in the aftermath of a severe Covid-19 in young subjects". The main objective of this study is to evaluate the incidence of post-Covid-19 post-traumatic disorders (post-traumatic stress disorder, psychogenic and somatoform dissociative tendency, neurological dissociative disorder) in a longitudinal way. This optional study will be offered to all patients from the main study who meet the selection criteria.

Inclusion Criteria:

• Patients between 18 and 65 years of age (at discharge of hospitalization),
• Patient hospitalized for more than 72 hours (in intensive care or conventional sector) for a COVID-19 infection defined by a positive PCR (Polymerase Chain Reaction) test and/or typical aspect on thoracic scanner,
• Patient discharged from hospital between 01/10/2020 and 01/04/2021,
• Patient with suspected cognitive impairment (obtaining a pathologic QPC score) during the phone screening,
• Patient having received complete information on the organization of the research and having given written informed consent (or a third person, independent of the investigator and the sponsor, in case of inability to read or write),
• Patient affiliated with a social security plan or beneficiary of such a plan,
• Patient with a sufficient level of written French comprehension to complete the cognitive assessment.

Exclusion Criteria:

• Inability to travel to perform the BNP or additional tests,
• Contraindication to perform brain MRI (pacemaker, etc.),
• Presence of chronic neurological diseases (multiple sclerosis, neurodegenerative disease, epilepsy) and/or major cognitive disorders (stroke, head trauma) pre-COVID-19,
• Presence of psychiatric disorder historys (bipolar or psychotic illness) pre-COVID-19,
• Patients with very extensive post-COVID-19 brain damage leading to impossibility to realise cognitive assessment,
• Addictive history or comorbidities (alcoholism, drug use) with sequelae of cognitive impairment,
• Persons covered by articles L. 1121-5, L. 1121-7 and L1121-8 of the Public Health Code.