The number of long duration human spaceflights has increased substantially over the past 15 years, leading to the discovery of numerous effects on the CNS. Microgravity results in headward fluid shifts, ventricular expansion, an upward shift of the brain within the skull, and remodelling of grey and white matter. The fluid changes are correlated with changes to perivascular space and spaceflight associated neuro-ocular syndrome. Microgravity alters the vestibular processing of head tilt and results in reduced tactile and proprioceptive inputs during spaceflight. Sensory adaptation is reflected in postflight effects, evident as transient sensorimotor impairment. Another major concern is that galactic cosmic radiation, which spacefarers will be exposed to when going beyond the magnetosphere around Earth, might have a negative effect on CNS function. Research with rodents points to the potential disruptive effects of space radiation on blood–brain barrier integrity and brain structures. More work is needed to understand and mitigate these effects on the CNS before humans travel to Mars, as the flight durations will be longer than anyone has previously experienced.

中文翻译：

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太空飞行对大脑的影响


过去 15 年里，长时间载人航天飞行的次数大幅增加，导致人们发现了对中枢神经系统的众多影响。微重力导致液体向上移动、心室扩张、颅骨内大脑向上移动以及灰质和白质的重塑。液体变化与血管周围空间的变化和航天相关的神经眼综合征相关。微重力改变了头部倾斜的前庭处理，导致太空飞行期间触觉和本体感觉输入减少。感觉适应反映在飞行后的影响中，表现为短暂的感觉运动障碍。另一个主要问题是，宇航员在离开地球磁层之外时会受到银河宇宙辐射，可能会对中枢神经系统功能产生负面影响。对啮齿动物的研究表明，太空辐射对血脑屏障完整性和大脑结构具有潜在的破坏性影响。在人类前往火星之前，需要做更多的工作来了解和减轻这些对中枢神经系统的影响，因为飞行时间将比任何人以前经历过的都要长。