Encyclopedia of Bioastronautics

Living Edition
| Editors: Laurence R. Young, Jeffrey P. Sutton

Modeling and Entraining Human Capability in Space

  • Elizabeth B. KlermanEmail author
  • Andrew J. K. Phillips
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-10152-1_32-1


Space operations are extraordinarily challenging endeavors, demanding high cognitive performance and alertness from both astronauts and ground-based crew. Due to the nature of the space environment and mission constraints, it can be difficult to entrain, or align, the body’s internal ~24.2-h circadian rhythm to the required day length (e.g., the 24-h Earth day or the 24.65-h Mars day), to adapt to shifts in sleep/wake or work schedules, and to obtain sufficient sleep. Both circadian rhythms and sleep physiology significantly affect human performance, alertness, mood, and other physiology. To address these concerns, mathematical models of human circadian rhythms, sleep, performance, and alertness have been developed. These models can be used to predict how individuals will function on different schedules, to suggest strategies to improve performance, to entrain circadian rhythms, and to optimize the use of countermeasures such as light, naps, and pharmaceuticals. These models...


Mathematical models Simulations Desynchronization Performance Circadian 
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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Elizabeth B. Klerman
    • 1
    Email author
  • Andrew J. K. Phillips
    • 2
  1. 1.Division of Sleep and Circadian Disorders, Department of MedicineBrigham and Women’s Hospital, Harvard Medical SchoolBostonUSA
  2. 2.School of Psychological SciencesMonash UniversityClaytonAustralia

Section editors and affiliations

  • David F. Dinges
    • 1
  1. 1.Department of PsychiatryUniversity of Pennsylvania, Perelman School of MedicinePhiladelphiaUSA