Cortical reorganization in an astronaut's brain after long-duration spaceflight.
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SUBMITTER: Demertzi A
PROVIDER: S-EPMC4884200 | biostudies-literature | 2016 Jun
REPOSITORIES: biostudies-literature
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Cortical reorganization in an astronaut's brain after long-duration spaceflight.
Demertzi Athena A Van Ombergen Angelique A Tomilovskaya Elena E Jeurissen Ben B Pechenkova Ekaterina E Di Perri Carol C Litvinova Liudmila L Amico Enrico E Rumshiskaya Alena A Rukavishnikov Ilya I Sijbers Jan J Sinitsyn Valentin V Kozlovskaya Inessa B IB Sunaert Stefan S Parizel Paul M PM Van de Heyning Paul H PH Laureys Steven S Wuyts Floris L FL
Brain structure & function 20150512 5
To date, hampered physiological function after exposure to microgravity has been primarily attributed to deprived peripheral neuro-sensory systems. For the first time, this study elucidates alterations in human brain function after long-duration spaceflight. More specifically, we found significant differences in resting-state functional connectivity between motor cortex and cerebellum, as well as changes within the default mode network. In addition, the cosmonaut showed changes in the supplement ...[more]
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Project description:ImportanceLong-duration spaceflight induces structural changes in the brain and eye. Identification of an association between cerebral and ocular changes could help determine if there are common or independent causes and inform targeted prevention strategies or treatments.ObjectiveTo determine if there is an association between quantitative changes in intracranial compartment volumes and peripapillary total retinal thickness after spaceflight.Design, setting, and participantsThis cohort study included healthy International Space Station crew members before and immediately after long-duration spaceflight. Data on race were not collected. Analysis was conducted from September to November 2020.ExposuresLong-duration spaceflight (mean [SD], 191 [55] days).Main outcomes and measuresOptical coherence tomography-derived peripapillary total retinal thickness as a quantitative assessment and early sign of optic disc edema and magnetic resonance imaging-derived measures of lateral ventricle volume, white matter volume, and whole brain plus cerebrospinal fluid volume.ResultsIn 19 healthy crew members included in this study (5 women [26.3%], 14 men [73.7%]; mean [SD] age, 45.2 [6.4] years), analyses revealed a positive, although not definitive, association between spaceflight-induced changes in total retinal thickness and lateral ventricle volume (4.7-μm increase in postflight total retinal thickness [95% CI, -1.5 to 10.8 μm; P = .13] per 1-mL postflight increase in lateral ventricle volume). Adjustments for mission duration improved the strength of association (5.1 μm; 95% CI, -0.4 to 10.5 μm; P = .07). No associations were detected between spaceflight-induced changes in total retinal thickness and white matter volume (0.02 μm; 95% CI, -0.5 to 0.5 μm; P = .94) or brain tissue plus cerebrospinal fluid volume, an estimate of intracranial volume (0.02 μm; 95% CI, -0.6 to 0.6 μm; P = .95).Conclusions and relevanceThese results help characterize spaceflight-associated neuro-ocular syndrome and the physiologic associations of headward fluid shifts with outcomes during spaceflight on the central nervous system. The possibly weak association between increased total retinal thickness and lateral ventricle volume suggest that while weightlessness-induced fluid redistribution during spaceflight may be a common stressor to the brain and retina, the development of optic disc edema appears to be uncoupled with changes occurring in the intracranial compartment.
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