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Sleep-Wake Actigraphy and Light Exposure During Spaceflight-Long (Sleep-Long)
01.27.10

Overview | Description | Applications | Operations | Results | Publications | Images

Experiment/Payload Overview

Brief Summary

Sleep-Wake Actigraphy and Light Exposure During Spaceflight-Long (Sleep-Long) will examine the effects of space flight and ambient light exposure on the sleep-wake cycles of the crewmembers during long-duration stays on the space station.

Principal Investigator

  • Charles A. Czeisler, M.D., Ph.D., Brigham and Women's Hospital, Harvard Medical School, Boston, MA
  • Laura K. Barger, Ph.D., Brigham and Women's Hospital, Harvard Medical School, Boston, MA

    • Co-Investigator(s)/Collaborator(s)

  • Kenneth P. Wright, Jr., Ph.D., University of Colorado, Boulder, CO
  • Joseph Ronda, Brigham and Women's Hospital, Boston, MA

    • Payload Developer

    Johnson Space Center, Human Research Program, Houston, TX

    Sponsoring Agency

    National Aeronautics and Space Administration (NASA)

    Expeditions Assigned

    |14|15|16|17|18 |19/20 |21/22 |23/24 |25/26|

    Previous ISS Missions

    Sleep-Short, a similar investigation was performed with short duration crewmembers during STS-104, STS-109, STS-111, STS-112, STS-113, STS-114, STS-121, STS-115, STS-116, STS-122, STS-123, STS-124, and STS-126.

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    Experiment/Payload Description

    Research Summary

    • Previous research on Space Shuttle crewmembers has shown that sleep-wake patterns are disrupted on orbit. This experiment will examine whether sleep-wake activity patterns are disrupted during long duration stays on the International Space Station (ISS).


    • A wrist-worn Actiwatch will record the activity of the crewmembers and the ambient light they experience.


    • Data collected from sleep logs will also be used to evaluate the crewmembers? subjective evaluation of the amount and quality of their sleep.


    • This work will help in defining light requirements, sleep-shifting protocols, and workload plans for future explorations missions, and determine if further countermeasures to sleep disruption will need to be tested.

    Description

    The success and effectiveness of manned spaceflight depends on the ability of crewmembers to maintain a high level of cognitive performance and vigilance while operating and monitoring sophisticated instrumentation. Astronauts during short duration space flights, however, commonly experience sleep disruption and may experience misalignment of circadian phase during spaceflight. Both of these conditions are associated with insomnia, and impairment of alertness and cognitive performance.

    There is little information on the effect of long-duration spaceflight on sleep and circadian rhythm organization. This experiment will use state of the art ambulatory technology to monitor sleep-wake activity patterns and light exposure in crewmembers aboard ISS. Subjects will wear a small, light-weight activity and light recording device (Actiwatch) for the entire duration of their mission. The sleep-wake activity and light exposure patterns obtained in-flight will be compared with baseline data collected on Earth before and after spaceflight. These data should help us better understand the effects of spaceflight on sleep as well as aid in the development of effective countermeasures for long-duration spaceflight.

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    Applications

    Space Applications

    The information derived from this study will help to better understand the effects of space flight on sleep-wake cycles. The countermeasures that will be developed will improve sleep during missions which in turn will help maintain alertness and lessen fatigue of the crew during long-duration space flights.

    Earth Applications

    A better understanding of insomnia is relevant to the millions of people on Earth who suffer nightly from insomnia. The advancement of state of the art technology for monitoring, diagnosing, and assessing treatment effectiveness is vital to the continued treatment of insomnia on Earth. This work could benefit the health, productivity and safety of groups with a high prevalence of insomnia, such as shift workers and the elderly.

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    Operations

    Operational Requirements

    A total of 20 long-duration crewmembers are needed as subjects for the experiment. Baseline data for each subject must be collected for two weeks between L-120 (launch minus 120 days) and L-75 and from L-11 through L-0. Recovery in sleep patterns after spaceflight will be assessed from R+0 (return plus 0 days) to R+7.

    Operational Protocols

    Crewmembers will put on the Actiwatches as soon as possible upon entry into orbit and wear them throughout the flight. Crewmembers will maintain sleep logs; they will be required to keep the log for seven consecutive days, for three separate weeks throughout the mission. Crewmembers will download data from the Actiwatches every 26 days and change the battery at the end of the increment. On the last day of the mission, crewmembers will doff and stow the Actiwatches.

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    Results/More Information

    Analysis of the Sleep-Long data is ongoing.

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    Related Web Sites
  • Sleep Medicine at Harvard Medical School
  • International Space Station Medical Project (ISSMP)

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    Publications

    Results Publications

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      Related Publications
      • Monk TH, Buysse DJ, Billy BJ. Using daily 30-min phase advances to achieve a 6-hour advance: Circadian rhythm, sleep, and alertness. Aviation Space and Environmental Medicine. ;77(7): 677-686. 2006
      • Mallis MM, DeRoishia CW. Circadian Rhythms, Sleep, and Performance in Space. Aviation Space and Environmental Medicine. ;76(6 Suppl): B94-107. 2005
      • Monk TH, Buysse DJ, Billy BD, DeGrazia JM. Using nine 2-h delays to achieve a 6-h advance disrupts sleep, alertness, and circadian rhythm. Aviation Space and Environmental Mediceine. ;75:1049-1057. 2004
      • Dijk D, Neri DF, Wyatt JK, Ronda JM, Riel E, Ritz-De Ceccoa A, Hughes RJ, Elliott AR, Prisk GK, West JB, Czeisler CA. Sleep, performance, circadian rhythms, and light-dark cycles during two space shuttle flights. American Journal of Physiology Regulatory Integrative Comparative Physiology. ;281:R1647-R1664. 2001

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      Images

      imageThis image of an Actiwatch Activity Monitor next to a ruler to demonstrate the size of the Actiwatch. Image courtesy of NASA.
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      imageNASA Image: S104E5114 - Astronaut, Janet Kavandi on STS-104 wearing an Actiwatch on her right wrist for recording activities.
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      imageNASA Image: ISS014E05119 - The Sleep-Long Actiwatch is visible on the left arm of Astronaut Michael Lopez-Alegria the Expedition 14 Commander. The Actiwatch monitors light and activity patterns of crewmembers.
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      imageNASA Image: ISS014E12135 - Expedition 14 Flight Engineer, Astronaut Suni Williams, performs her daily tasks while wearing the Actiwatch device as seen on her left arm in the lower portion of this image.
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      imageNASA Image: ISS015E09441 - Expeditions 14 and 15 Astronaut and Flight Engineer (FE-2), Sunita Williams, is seen here entering data at a computer workstation for the Sleep-Wake Actigraphy and Light Exposure During Spaceflight-Long (Sleep-Long) experiment in the U.S. Laboratory/Destiny.
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      Information Provided and Updated by the ISS Program Scientist's Office
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