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Operational Ground Testing Protocol to Optimize Astronaut Sleep Medication Efficacy and Individual Effects (Sleep_Meds_Phase_II)
Principal Investigator
Research Area:
Behavior and performance
Species Studied
Scientific Name: Homo sapiens Species: Human

Recent data indicate that some crewmembers take medications twice in one night. The sleep medications used in space flight are FDA approved for sleep periods of eight hours or more, but they have not been studied for their effects on waking cognitive functions during an alarm-based awakening from sleep (under eight hours) that has occurred in space flight numerous times. There is a need to identify the cognitive effects of sleep medications during such premature awakenings, and to identify the sleep medications and dosages that produce the fewest cognitive effects and adverse reactions in individual astronauts. Consequently, the study aimed to characterize the effects of the most commonly used sleep medications and dosages on performance after an unplanned awakening, while providing the foundation for future development of individualized protocols for sleep medication use during training and on-orbit.

The pilot study was successfully tested on seven subjects from March through June, 2009. The pilot study results supported the scientific feasibility of conducting a randomized, blinded, placebo controlled study of sleep medication effects on simulated alarm-based awakenings. Preliminary analysis from the pilot study indicated differences in performance upon abrupt awakening between the sleep medication and placebo conditions. Thus, the pilot data also support the likelihood of new scientific and clinical insights from the Phase II studies with NASA astronauts.

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Task performance and analysis

Data Information
Data Availability
Archive is complete. Data sets are not publicly available but can be requested.
Data Sets+ Request data

Cognitive performance
Descending subtraction task (DST) number correct
Descending subtraction task (DST) number of errors
Mental fatigue ratings, mean
Physical exhaustion ratings, mean
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Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Ground 05/01/2009 In Progress

Human Research Program (HRP) Human Research Roadmap (HRR) Information
Crew health and performance is critical to successful human exploration beyond low Earth orbit. The Human Research Program (HRP) investigates and mitigates the highest risks to human health and performance, providing essential countermeasures and technologies for human space exploration. Risks include physiological and performance effects from hazards such as radiation, altered gravity, and hostile environments, as well as unique challenges in medical support, human factors, and behavioral health support. The HRP utilizes an Integrated Research Plan (IRP) to identify the approach and research activities planned to address these risks, which are assigned to specific Elements within the program. The Human Research Roadmap is the web-based tool for communicating the IRP content.

The Human Research Roadmap is located at:

+ Click here for information of how this experiment is contributing to the HRP's path for risk reduction.

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Pamela A. Bieri
Institutional Support
National Aeronautics and Space Administration (NASA)
Proposal Date
Proposal Source
Directed Research