Sex-Dependent Changes in Risk-Taking Predisposition of Rats Following Space Radiation Exposure

The Artemis missions will establish a sustainable human presence on the Moon, serving as a crucial steppingstone for future Mars exploration. Astronauts on these ambitious missions will have to successfully complete complex tasks, which will frequently involve rapid and effective decision making under unfamiliar or high-pressure conditions. Exposure to low doses of space radiation (SR) can impair key executive functions critical to decision making. This study examined the effects of exposure to 10 cGy of Galactic Cosmic Ray simulated radiation (GCRsim) on decision-making performance in male and female rats with a naturally low predisposition for risk-taking (RTP) prior to exposure. Rats were assessed at monthly intervals following SR exposure and the RTP performance contrasted with that observed during the prescreening process. Exposure to 10 cGy of GCRsim impaired decision making in both male and female rats, with sex-dependent outcomes. By 30 days after SR exposure, female rats became more risk-prone, making less profitable decisions, while male rats retained their decision-making strategies but took significantly longer to make selections. However, continued practice in the RTP tasks appeared to reduce/reverse these performance deficits. This study has expanded our understanding of the range of cognitive processes impacted by SR to include decision making.