Abstract：
The planned missions to the Moon and Mars will present more significant health challenges to astronauts compared to low earth orbit missions. During deep space missions, astronauts will be constantly exposed to Space radiation (SR). Multiple rodent studies suggest that < 25 cGy of SR impairs performance in executive functions, which play a key role in advanced cognitive processes, but also regulate response inhibition and impulse control. There is the possibility that SR exposure may exacerbate aberrant behaviors evoked by psychological stress related to exposure to isolated and confined (ICE) hostile environment or independently induce additional aberrant behaviors. This study has determined that female Wistar rats exposed to 10 cGy of 250 MeV/n He had an increased risk taking propensity (RTP)\\compared to shams. The increased RTP of the He-exposed rats was associated with significantly increased reaction times during the trials, suggesting a SR-induced loss of processing speed. The response times of the He-exposed rats were even further reduced in trials that immediately followed a loss, raising the possibility that conflict and interference avoidance may be impaired after SR exposure. Whether these findings occur following other types of SR exposure, and/or in male rats remains to be determined.
摘要：
与低地球轨道任务相比，计划中的月球和火星任务将给宇航员带来更大的健康挑战。在深空任务中,宇航员将不断受到空间辐射（SR）。多项啮齿动物研究表明，<25cGy的SR会损害执行功能的表现，在高级认知过程中起着关键作用，而且还调节反应抑制和冲动控制。SR暴露可能会加剧与暴露于孤立和封闭（ICE）敌对环境有关的心理压力引起的异常行为，或独立地诱发其他异常行为。这项研究已经确定，暴露于250MeV/nHe的10cGy的雌性Wistar大鼠具有增加的风险承担倾向（RTP），选择风险较高的选项的比率显着（P<0.05）高于假同窝动物。KDE分析显示，与Sham相比，暴露于He的大鼠可能被归类为风险倾向（>50％的风险选择）约1.7倍。在试验期间，He暴露大鼠的RTP增加与反应时间显着增加有关，表明SR引起的处理速度损失。在丢失后立即进行的试验中，He暴露大鼠的响应时间甚至进一步减少，提高了SR暴露后冲突和干扰避免可能受到损害的可能性。这些发现是否发生在其他类型的SR暴露之后，和/或在雄性大鼠中仍有待确定。
