Related Experiment Video
Updated: Apr 5, 2026
Coherence between Brain Cortical Function and Neurocognitive Performance during Changed Gravity Conditions
Published on: May 23, 2011
Effect of Simulated Microgravity on Human Brain Gray Matter and White Matter--Evidence from MRI
Ke Li1, Xiaojuan Guo2, Zhen Jin3
1Department of Radiology, Chinese PLA General Hospital, Beijing, China; Magnetic Resonance Center, 306 Hospital of PLA, Beijing, China.
Background:
There is limited and inconclusive evidence that space environment, especially microgravity condition, may affect microstructure of human brain. This experiment hypothesized that there would be modifications in gray matter (GM) and white matter (WM) of the brain due to microgravity.
Method:
Eighteen male volunteers were recruited and fourteen volunteers underwent -6° head-down bed rest (HDBR) for 30 days simulated microgravity. High-resolution brain anatomical imaging data and diffusion tensor imaging images were collected on a 3T MR system before and after HDBR. We applied voxel-based morphometry and tract-based spatial statistics analysis to investigate the structural changes in GM and WM of brain.
Results:
We observed significant decreases of GM volume in the bilateral frontal lobes, temporal poles, parahippocampal gyrus, insula and right hippocampus, and increases of GM volume in the vermis, bilateral paracentral lobule, right precuneus gyrus, left precentral gyrus and left postcentral gyrus after HDBR. Fractional anisotropy (FA) changes were also observed in multiple WM tracts.
Conclusion:
These regions showing GM changes are closely associated with the functional domains of performance, locomotion, learning, memory and coordination. Regional WM alterations may be related to brain function decline and adaption. Our findings provide the neuroanatomical evidence of brain dysfunction or plasticity in microgravity condition and a deeper insight into the cerebral mechanisms in microgravity condition.
Insights
Simulated microgravity from head-down bed rest altered human brain structure. Researchers observed changes in gray matter (GM) and white matter (WM) volumes and integrity, suggesting brain plasticity and adaptation.
Area of Science:
- Neuroscience
- Space Medicine
- Human Physiology
Background:
- Limited evidence exists on microgravity's effects on human brain microstructure.
- This study investigated potential modifications in gray matter (GM) and white matter (WM) due to simulated microgravity.
Purpose of the Study:
- To test the hypothesis that microgravity induces structural changes in the human brain.
- To identify specific regions of gray matter and white matter alterations.
Main Methods:
- Fourteen male volunteers underwent 30 days of -6° head-down bed rest (HDBR) to simulate microgravity.
- High-resolution MRI, including diffusion tensor imaging, was used before and after HDBR.
- Voxel-based morphometry and tract-based spatial statistics analyzed structural changes.
Main Results:
- Significant decreases in GM volume were observed in frontal lobes, temporal poles, parahippocampal gyrus, insula, and right hippocampus.
- GM volume increased in the vermis, paracentral lobule, precuneus gyrus, precentral gyrus, and postcentral gyrus.
- Fractional anisotropy (FA) changes indicated alterations in multiple white matter tracts.
Conclusions:
- Observed GM changes correlate with functions like performance, locomotion, learning, memory, and coordination.
- WM alterations suggest potential brain function decline or adaptation in microgravity.
- Findings provide neuroanatomical evidence of brain plasticity and mechanisms underlying microgravity effects.
