Chang Hui Ho Vanessa, Fesshaye Arriyam S, Tidmore Alyssa, Sanford Larry D, Britten Richard A
Radiation Oncology.
Biomedical and Translational Sciences.
Radiat Res. 2025 Jan 1;203(1):18-25. doi: 10.1667/RADE-24-00146.1.
The prolonged exposure to multiple spaceflight stressors during long-duration missions to the Moon and Mars will be challenging to the physical and mental health of the astronauts. Ground-based studies have reported that attentional set-shifting task (ATSET) performance is impaired after space radiation (SR) exposure. At certain times during deep-space missions, astronauts will likely have to contend with the combined impacts of SR and sleep perturbation. In rats, poor quality, fragmented sleep adversely impacts performance in multiple cognitive tasks, including the ATSET task. While both SR and sleep perturbations independently cause cognitive performance deficits, the incidence, severity and exact nature of those decrements following combined exposure to these flight stressors is largely unknown. This study established the impact that a single night of fragmented sleep has on ATSET performance in both male and female rats exposed to 10 cGy of galactic cosmic ray simulation (GCRsim). The GCRsim beam is a complex beam that mimics the mass and energy spectra of the SR particles that an astronaut will be exposed to within the spacecraft. Rats that had no obvious ATSET performance decrements when normally rested were subjected to fragmented sleep and their ATSET performance reassessed. Sleep fragmentation resulted in significant ATSET performance decrements in GCRsim-exposed rats, with specific performance decrements being observed in stages where attention or cue shifting is extensively used. Performance decrements in these stages are rarely observed after SR exposure. While both male and female rats exhibited latent sleep-related performance decrements, these were sex dependent, with male and female rats exhibiting different types of performance decrements (either reduced processing speed or task completion efficiency) in different stages of the ATSET task. This study suggests that SR-induced cognitive impairment may not be fully evident in normally rested rats, with an underestimation of both the incidence and nature of performance decrements that could occur when multiple space flight stressors are present. These data suggest that that there may be synergistic interactions between multiple space flight stressors that may not be easily predicted from their independent actions.
在前往月球和火星的长期任务中，宇航员长时间暴露于多种太空飞行应激源将对其身心健康构成挑战。地面研究报告称，暴露于太空辐射（SR）后，注意力转换任务（ATSET）的表现会受到损害。在深空任务的某些时段，宇航员可能不得不应对太空辐射和睡眠紊乱的综合影响。在大鼠中，低质量、碎片化的睡眠会对包括ATSET任务在内的多项认知任务的表现产生不利影响。虽然太空辐射和睡眠紊乱都会独立导致认知表现缺陷，但在同时暴露于这些飞行应激源后，这些缺陷的发生率、严重程度和确切性质在很大程度上尚不清楚。本研究确定了一夜碎片化睡眠对暴露于10 cGy银河宇宙射线模拟（GCRsim）的雄性和雌性大鼠ATSET表现的影响。GCRsim束是一种复杂的束流，可模拟宇航员在航天器内将暴露于的太空辐射粒子的质量和能谱。对正常休息时ATSET表现无明显下降的大鼠进行碎片化睡眠处理，并重新评估其ATSET表现。睡眠碎片化导致暴露于GCRsim的大鼠ATSET表现显著下降，在广泛使用注意力或线索转换的阶段观察到了特定的表现下降。在太空辐射暴露后，很少在这些阶段观察到表现下降。虽然雄性和雌性大鼠都表现出与睡眠相关的潜在表现下降，但这些下降具有性别依赖性，雄性和雌性大鼠在ATSET任务的不同阶段表现出不同类型的表现下降（处理速度降低或任务完成效率降低）。本研究表明，太空辐射引起的认知障碍在正常休息的大鼠中可能并不完全明显，可能会低估在存在多种太空飞行应激源时可能发生的表现下降的发生率和性质。这些数据表明，多种太空飞行应激源之间可能存在协同相互作用，而这些相互作用可能无法从它们的独立作用中轻易预测出来。
