Vol.:(0123456789) 1 3 Experimental Brain Research https://doi.org/10.1007/s00221-019-05531-0 RESEARCH ARTICLE Neurophysiological, neuropsychological, and cognitive efects of 30 days of isolation Jan Weber 1  · Florian Javelle 2  · Timo Klein 1  · Tina Foitschik 1  · Brian Crucian 3  · Stefan Schneider 1  · Vera Abeln 1 Received: 12 July 2018 / Accepted: 25 March 2019 © Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract The increasing demand of space fights requires a profound knowledge of the chronologic reactions of the human body to extreme conditions. Prior studies already have shown the adverse efects of long-term isolation on psycho-physiological well-being. The chronology of the efects and whether short-term isolation periods already lead to similar efects has not been investigated. Therefore, the aim of the current study was to investigate the efects of short-term isolation (30 days) on mood, cognition, cortisol, neurotrophic factors, and brain activity. 16 participants were isolated in the Human Exploration Research Analog at NASA for 30 days. 17 non-isolated control participants were tested simultaneously. On mission days − 5, 7, 14, 28, and + 5, multiple tests including the Positive and Negative Afect Schedule-X and cognitive tests were conducted, and a 5-min resting electroencephalography was recorded. A fasted morning blood drawing was also done. Increased stress was observed via augmented cortisol levels during the isolation period. Activity within the parietal cortex was reduced over time, probably representing a neural adaptation to less external stimuli. Cognitive performance was not afected, but rather enhanced in both groups. No further signifcant changes in neurotrophic factors BDNF/IGF-1 and mood could be detected. These results suggest that 30 days of isolation do not have a signifcant impact on brain activity, neurotrophic factors, cogni- tion, or mood, even though stress levels were signifcantly increased during isolation. Further studies need to address the question as to what extent increased levels of stress do not afect mental functions during isolation periods. Keywords Isolation · Cortisol · Neurotrophic factors · Brain activity · Mood · Cognition Abbreviations HPA Hypothalamic–pituitary–adrenal axis BDNF Brain-derived neurotrophic factor IGF-1 Insulin-like growth factor 1 LORETA Low-resolution brain electromagnetic tomography HERA Human exploration research analog IG Isolation group CG Control group MD Mission day PANAS-X Positive and negative afect schedule-X GPA General positive afect GNA General negative afect EEG Electroencephalography ACTH Adrenocorticotropic hormone PFC Prefrontal cortex Introduction Since there is an increasing demand of space fights to chart new territories as well as a planned manned mission to Mars, the issues accompanied during long-term space fights have become a central topic in space research (Bachman et al. 2012). Long-term space fights are a signifcant challenge for crewmembers due to stressful environmental conditions (Basner et al. 2014) which can be described as isolated, confned, and hostile (Palinkas 2007). Even if space fights represent state-of-the-art technological progress, isolation is still a major stressor and, therefore, a justifed present concern, as it impairs regulation of mood, cognitive per- formance, stress hormones, neurotrophic factors, and brain * Jan Weber jan.weber@student.uni-tuebingen.de 1 Institute of Movement and Neurosciences, German Sport University, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany 2 Institute for Cardiology and Sports Medicine, German Sport University, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany 3 NASA-Johnson Space Center, Houston, TX, USA