This study investigates the time course and magnitude of eight months of isolation and confinement in a spaceflight analog facility on brain changes and cognitive performance. The study also assesses the feasibility of an immersive and interactive virtual environment (VE) to enhance positive affect and mental well-being during prolonged isolation and confinement.

The study investigates the neurobehavioural risks associated with future exploratory space missions and their mitigation as part of the isolation and confinement program "SIRIUS" (Scientific International Research In Unique terrestrial Station). The overarching objective of the study is two-fold.

The first objective is to investigate the time course and magnitude of eight months of isolation and confinement in the spaceflight analog facility "NEK" at the Institute of Biomedical Problems (IBMP) in Moscow on brain changes, cognitive performance, and biochemical adaptations, and compare these data to a sex- and age-matched control group. To achieve this aim, multi-modal magnetic resonance imaging (MRI) data before and after the intervention to assess structural and functional brain changes before, and after the experiment will be collected. Furthermore, cognitive performance using a series of computer-based tests will be determined and blood and saliva samples to identify biochemical changes associated with brain plasticity and learning before, during, and after the experiment will be collected.

Second, to address the need for sensory stimulation countermeasures during prolonged isolation and confinement, the feasibility of a highly immersive and interactive virtual environment (VE) to enhance positive affect and mental well-being will be assessed. To achieve this aim, the acute physiological and behavioral effects associated with the proposed sensory augmentation measure will be quantified (Does VE elicit immediate physiological and/or behavioral changes during long-duration isolation and confinement?). It will be verified whether there is an adaptation to the experience with repeated exposure bouts (Can VE elicit similar physiological and or behavioral responses after the VE exposure has been administered recurrently?). The administration rate is optimized relative to crew burden/compliance and scientific return (one administration once a month). This will also ensure that the approach will not have any chronic effects interfering with the primary outcomes of the first objective or any countermeasures foreseen by IBMP. These data will provide essential insights about the efficacy of a new, highly immersive, and target specific VR-based sensory stimulation augmentation to mitigate some of the risks associated with sensory monotony and visual disconnection from Earth during exploration-type missions. The two objectives will deliver a highly unique and comprehensive set of integrated neuroimaging and neurocognitive tools for the evaluation and ultimately prevention of adverse effects on brain plasticity and behavior.

Inclusion Criteria:

• Candidates who are professionals in the aerospace industry or related fields are eligible at a lower age limit of 28
• Height not to exceed 180 cm.
• Willing to be confined and isolated for up to 8 months.
• English and Russian verbal and written proficiency not lower than intermediate
• Absence of chronic disease or psychological deviations

Exclusion Criteria:

• Everybody who does not meet listed above requirements
• Past mental, cardiovascular, musculoskeletal and/or neurovestibular disorders or diseases
• Pronounced orthostatic intolerance or vestibular balance disorders (kinetosis)
• Abuses of drugs, medication or alcohol
• Claustrophobia
• Malnutrition up to 6 months before the start of the study
• Intake of anabolic steroids up to 6 months before study initiation
• Metal implants or other osteosynthesis materials
• Bisphosphonate therapy
• Taking medication that could influence the results of the examination.
• Taking hormonal contraceptives in the last 6 months before the start of the study
• Menstrual disorders
• Delivery up to 6 months before the start of studies
• clinically manifest abnormalities in the resting ECG that preclude participation in the study
• Hypertension (> 130/85 mmHg)
• Increased risk of thrombosis
• Increased risk of stroke
• Infection with HIV or HBV
• HIV, hepatitis A, B, or tuberculosis infection
• clinically manifest changes in the differential blood count
• Clinically manifest changes according to the Comprehensive Metabolic Panel (CMP) (blood urea, uric acid, creatinine, total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), Alkaline Phosphatase (ALP), L-Lactate dehydrogenase (LDH), Glutamyltransferase (GGT), sodium, potassium, chloride, phosphorus, calcium, magnesium, CO2, total protein, albumin, globulin, fasting glucose (< 100mg/dL)
• clinically manifest iron deficiency: < 10 mg/L or < 20 mg/L for women and men respectively
• clinically manifest lipid metabolism disorders
• clinically manifest vitamin D deficiency
• clinical manifest increase of C-reactive protein
• Tuberculosis infection
• Gastroesophageal reflux
• Ulcers
• Kidney disease and/or kidney stones
• Thyroid dysfunction
• Tinnitus
• Sensorineural hearing loss from 30 dB
• Pacemaker or internal defibrillator
• metallic implants (e.g. orthopaedic plates after bone fractures, joint replacement, surgical clips or staples, artificial heart valves, vein filters)
• metallic splinters (e.g. after an accident or because of war injury)
• non-removable braces
• Tattoos with unknown color composition
• Permanent Make-up
• Cochlear implant (implanted hearing aid)
• Medication pump
• Acupuncture needles
• Any other condition which, in the opinion of the investigator, renders the subject unfit for inclusion in the study