Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United States.
KBR, 601 Jefferson Street, Houston, TX 77002, United States.
Cereb Cortex. 2023 Mar 10;33(6):2641-2654. doi: 10.1093/cercor/bhac232.
We studied the longitudinal effects of approximately 6 months of spaceflight on brain activity and task-based connectivity during a spatial working memory (SWM) task. We further investigated whether any brain changes correlated with changes in SWM performance from pre- to post-flight. Brain activity was measured using functional magnetic resonance imaging while astronauts (n = 15) performed a SWM task. Data were collected twice pre-flight and 4 times post-flight. No significant effects on SWM performance or brain activity were found due to spaceflight; however, significant pre- to post-flight changes in brain connectivity were evident. Superior occipital gyrus showed pre- to post-flight reductions in task-based connectivity with the rest of the brain. There was also decreased connectivity between the left middle occipital gyrus and the left parahippocampal gyrus, left cerebellum, and left lateral occipital cortex during SWM performance. These results may reflect increased visual network modularity with spaceflight. Further, increased visual and visuomotor connectivity were correlated with improved SWM performance from pre- to post-flight, while decreased visual and visual-frontal cortical connectivity were associated with poorer performance post-flight. These results suggest that while SWM performance remains consistent from pre- to post-flight, underlying changes in connectivity among supporting networks suggest both disruptive and compensatory alterations due to spaceflight.
我们研究了大约 6 个月的太空飞行对空间工作记忆（SWM）任务期间大脑活动和基于任务的连接的纵向影响。我们进一步调查了任何与飞行前到飞行后的 SWM 表现变化相关的大脑变化。在宇航员（n=15）执行 SWM 任务时，使用功能磁共振成像测量大脑活动。数据在飞行前采集了两次，飞行后采集了 4 次。由于太空飞行，SWM 表现或大脑活动没有明显变化；然而，大脑连接的显著预到后飞行变化是明显的。与大脑其他部位的任务相关连接，上枕叶在前到后飞行中减少。在执行 SWM 时，左中枕叶与左海马旁回、左小脑和左外侧枕叶皮质之间的连接也减少了。这些结果可能反映了飞行时视觉网络模块化的增加。此外，视觉和视觉运动连接的增加与飞行前到飞行后的 SWM 表现提高相关，而视觉和视觉额叶皮质连接的减少与飞行后的表现较差相关。这些结果表明，虽然 SWM 表现从飞行前到飞行后保持一致，但支持网络之间的连接变化表明，由于太空飞行，存在破坏和补偿性的改变。
