Multi-domain cognitive assessment of male mice reveals whole body exposure to space radiation is not detrimental to high-level cognition and actually improves pattern separation.

摘要: Astronauts on interplanetary space missions - such as to Mars will be exposed radiation, a spectrum of highly-charged, fast-moving particles that includes 56Fe and 28Si. Earth-based preclinical studies with mature, 9astronaut-aged9 rodents show radiation decreases performance in low- some high-level cognitive tasks. Given the prevalence touchscreens astronaut training in-mission assessment, ability rodent touchscreen tasks assess functional integrity brain circuits multiple domains non-aversive way, it is surprising effect unknown. To fill this knowledge gap, 6-month-old C57BL/6J male mice were whole-body assessed battery starting 1-month later. Relative Sham, irradiation did not overtly change visual discrimination, reversal learning, rule-based, or object-spatial paired associates suggesting preserved supporting circuits. Surprisingly, led better dentate gyrus-reliant task pattern separation ability. Irradiated discriminated similar cues ~40% fewer days more accurately than control mice. Improved was touchscreen-, radiation-particle, neurogenesis-dependent, both 28Si faster context discrimination (e.g. Sham Block 5 vs. 2) non-touchscreen new gyrus neurons relative Sham. These data urge revisitation broadly-held view detrimental cognition.