Task Countermeasures for Mitigation of Spaceflight Associated Neuro-ocular Syndrome, Ground Study
Last Published:  07/31/19 10:05:33 AM (Central)
Short Title: SANS Ground Analog CM
Responsible HRP Element: Human Health Countermeasures
Collaborating Org(s):
Funding Status: Planned-Funded - Task expected to be within budget
Procurement Mechanism(s):

This Task is a placeholder for a study in response to the HERO NRA 18 Appendix C solicitation topic:

Mechanisms and Evaluation of Countermeasures for Mitigation of Spaceflight Associated Neuro-ocular Syndrome (SANS) in a Novel Ground-Based Head-Down Tilt Bed Rest Analog


This solicitation topic is seeking proposals for ground-based evaluation of countermeasures that prevent or mitigate the signs and symptoms associated with Spaceflight Associated Neuro-ocular Syndrome (SANS) and SANS-related behavioral outcomes including cognition, sleep, and mood, as well as investigation of potential mechanisms by which SANS occurs in this ground-based analog.

The bed rest campaign for which proposals are being sought will consist of at least four arms, depending on the selected proposals, each lasting 30 days:

  1. A “posture-control”-arm, where for the 30-day duration the subjects will be seated during the daytime and supine when sleeping (16 hrs. seated vs. 8 hrs. supine). This is a unique approach that has not been used before in bed rest research, but which is considered necessary to explore further:

    1. The mechanistic aspects of the fluid shift induced manifestations of SANS.

    2. Whether the behavioral/cognitive changes as well as the objective and subjective aspects of mood and sleep (which as noted above were correlated with the degree of thickening of retinal tissues) are associated with the fluid shifts and whether they are related to any degree of edema formation in the brain.

    3. A better insight into the mechanisms of the tested countermeasures in the other bed rest arms.

  2. A 6° head-down tilt "no countermeasure"-control arm. For this arm of the study, NASA will consider proposals that will evaluate the mechanisms of the SANS ocular changes. Both fluid-shift based as well as other potential mechanisms are of interest.

  3. A 6° head-down tilt “Mechanical countermeasures”-arm to test a specific mechanical countermeasure developed by NASA (protocol will be shared with the selected investigators once available). The mechanical countermeasure will likely consist of a combination of LBNP, VTC, and ITD (all of these are under investigation at present, with the optimized combined mechanical countermeasure to be determined at the conclusion of the study that is currently underway).

  4. A 6° head-down tilt bed rest arm, where other types of countermeasure interventions (i.e., that do not duplicate the mechanical countermeasure used in the “mechanical countermeasures”-arm) can be tested and for example, compared to outcomes of the two control and the mechanical countermeasure arm, respectively.