Brain plasticity; FMRI; Functional connectivity; Microgravity; Spaceflight; Support afferentation; Support stimulation; Vestibular function
Abstract :
[en] The present study reports alterations of task-based functional brain connectivity in a group of 11 cosmonauts after a long-duration spaceflight, compared to a healthy control group not involved in the space program. To elicit the postural and locomotor sensorimotor mechanisms that are usually most significantly impaired when space travelers return to Earth, a plantar stimulation paradigm was used in a block design fMRI study. The motor control system activated by the plantar stimulation involved the pre-central and post-central gyri, SMA, SII/operculum, and, to a lesser degree, the insular cortex and cerebellum. While no post-flight alterations were observed in terms of activation, the network-based statistics approach revealed task-specific functional connectivity modifications within a broader set of regions involving the activation sites along with other parts of the sensorimotor neural network and the visual, proprioceptive, and vestibular systems. The most notable findings included a post-flight increase in the stimulation-specific connectivity of the right posterior supramarginal gyrus with the rest of the brain; a strengthening of connections between the left and right insulae; decreased connectivity of the vestibular nuclei, right inferior parietal cortex (BA40) and cerebellum with areas associated with motor, visual, vestibular, and proprioception functions; and decreased coupling of the cerebellum with the visual cortex and the right inferior parietal cortex. The severity of space motion sickness symptoms was found to correlate with a post-to pre-flight difference in connectivity between the right supramarginal gyrus and the left anterior insula. Due to the complex nature and rapid dynamics of adaptation to gravity alterations, the post-flight findings might be attributed to both the long-term microgravity exposure and to the readaptation to Earth's gravity that took place between the landing and post-flight MRI session. Nevertheless, the results have implications for the multisensory reweighting and gravitational motor system theories, generating hypotheses to be tested in future research.
Disciplines :
Neurology
Author, co-author :
Pechenkova, E. V.; National Research University, Higher School of Economics, Russian Federation
Nosikova, I. N.; Institute of Biomedical Problems (RAS), Russian Federation
Rumshiskaya, A. D.; Therapeutic and Rehabilitation Center, Ministry of Health of Russia, Russian Federation
Litvinova, L. D.; Therapeutic and Rehabilitation Center, Ministry of Health of Russia, Russian Federation
Rukavishnikov, I. V.; Institute of Biomedical Problems (RAS), Russian Federation
Mershina, E. A.; Medical Research and Education Center, Lomonosov Moscow State University, Russian Federation
Sinitsin, V. E.; Medical Research and Education Center, Lomonosov Moscow State University, Russian Federation
Alterations of functional brain connectivity after long-duration spaceflight as revealed by fMRI
Publication date :
2019
Journal title :
Frontiers in Physiology
eISSN :
1664-042X
Publisher :
Frontiers Media S.A., Switzerland
Volume :
10
Issue :
MAY
Pages :
23
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
RAS - Russian Academy of Sciences FWO - Fonds Wetenschappelijk Onderzoek Vlaanderen BELSPO - Belgian Science Policy Office RAS - Russian Academy of Sciences NEuropean Space Agency, ESA: ISLRA 2009-1062