DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Neural Correlates of Vestibular Processing During a Spaceflight Analog With Elevated Carbon Dioxide (CO₂): A Pilot Study

Hupfeld, Kathleen and Lee, Jessica K. and Gadd, Nichole E. and Kofman, Igor S. and De Dios, Yiri E. and Bloomberg, Jacob J. and Mulavara, Ajitkumar P. and Seidler, Rachael D. (2020) Neural Correlates of Vestibular Processing During a Spaceflight Analog With Elevated Carbon Dioxide (CO₂): A Pilot Study. Frontiers in Systems Neuroscience, 13, p. 80. Frontiers Media S.A.. doi: 10.3389/fnsys.2019.00080. ISSN 1662-5137.

[img] PDF - Published version

Official URL: https://www.frontiersin.org/articles/10.3389/fnsys.2019.00080/full


Astronauts return to Earth from spaceflight missions with impaired mobility and balance; recovery can last weeks postflight. This is due in large part to the altered vestibular signaling and sensory reweighting that occurs in microgravity. The neural mechanisms of spaceflight-induced vestibular changes are not well understood. Head-down-tilt bed rest (HDBR) is a common spaceflight analog environment that allows for study of body unloading, fluid shifts, and other consequences of spaceflight. Subjects in this context still show vestibular changes despite being in Earth’s gravitational environment, potentially due to sensory reweighting. Previously, we found evidence of sensory reweighting and reduced neural efficiency for vestibular processing in subjects who underwent a 70-day HDBR intervention. Here we extend this work by evaluating the impact of HDBR paired with elevated carbon dioxide (CO₂) to mimic International Space Station conditions on vestibular neural processing. Eleven participants (6 males, 34 ± 8 years) completed 30 days of HDBR combined with 0.5% atmospheric CO₂ (HDBR + CO₂). Participants underwent six functional magnetic resonance imaging (fMRI) sessions pre-, during, and post- HDBR + CO₂ while we measured brain activity in response to pneumatic skull taps (a validated method of vestibular stimulation). We also measured mobility and balance performance several times before and after the intervention. We found support for adaptive neural changes within the vestibular system during bed rest that subsequently recovered in several cortical and cerebellar regions. Further, there were multiple brain regions where greater pre- to post- deactivation was associated with reduced pre- to post- balance declines. That is, increased deactivation of certain brain regions associated with better balance post-HDBR + CO₂. We also found that, compared to HDBR alone (n = 13 males; 29 ± 3 years) HDBR + CO₂ is associated with greater increases in activation of multiple frontal, parietal, and temporal regions during vestibular stimulation. This suggests interactive or additive effects of bed rest and elevated CO₂. Finally, we found stronger correlations between pre- to postHDBR + CO₂ brain changes and dependence on the visual system during balance for subjects who developed signs of Spaceflight-Associated Neuro-ocular Syndrome Frontiers in Systems Neuroscience | www.frontiersin.org 1 January 2020 | Volume 13 | Article 80Hupfeld et al. Neural Vestibular Processing With HDBR + CO₂ (SANS). Together, these findings have clear implications for understanding the neural mechanisms of bed rest and spaceflight-related changes in vestibular processing, as well as adaptation to altered sensory inputs.

Item URL in elib:https://elib.dlr.de/135896/
Document Type:Article
Title:Neural Correlates of Vestibular Processing During a Spaceflight Analog With Elevated Carbon Dioxide (CO₂): A Pilot Study
AuthorsInstitution or Email of AuthorsAuthor's ORCID iD
Hupfeld, KathleenDepartment of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United StatesUNSPECIFIED
Lee, Jessica K.German Aerospace Center, Institute of Aerospace Medicine, Cologne, GermanyUNSPECIFIED
Gadd, Nichole E.KBR, Houston, TX, United StatesUNSPECIFIED
Kofman, Igor S.KBR, Houston, TX, United StatesUNSPECIFIED
De Dios, Yiri E.KBR, Houston, TX, United StatesUNSPECIFIED
Bloomberg, Jacob J.NASA Johnson Space Center, Houston, TX, United StatesUNSPECIFIED
Mulavara, Ajitkumar P.KBR, Houston, TX, United StatesUNSPECIFIED
Seidler, Rachael D.Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United StatesUNSPECIFIED
Date:10 January 2020
Journal or Publication Title:Frontiers in Systems Neuroscience
Refereed publication:Yes
Open Access:Yes
Gold Open Access:Yes
In ISI Web of Science:Yes
Page Range:p. 80
Publisher:Frontiers Media S.A.
Keywords:vestibular, fMRI, head-down-tilt bed rest (HDBR), carbon dioxide (CO₂), spaceflight
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Research under Space Conditions
DLR - Research area:Raumfahrt
DLR - Program:R FR - Research under Space Conditions
DLR - Research theme (Project):R - Vorhaben Systemphysiologie (old)
Location: Köln-Porz
Institutes and Institutions:Institute of Aerospace Medicine > Muscle and Bone Metabolism
Deposited By: Arndt, Carina
Deposited On:08 Sep 2020 12:58
Last Modified:30 Sep 2020 09:36

Repository Staff Only: item control page

Help & Contact
electronic library is running on EPrints 3.3.12
Website and database design: Copyright © German Aerospace Center (DLR). All rights reserved.