Performance in hippocampus- and PFC-dependent cognitive domains are not concomitantly impaired in rats exposed to 20 cGy of 1 GeV/n ⁵⁶Fe particles

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• 作者：Richard A. Britten^a ; ^b ; ^c ; ^{brittera@evms.edu" class="auth_mail" title="E-mail the corresponding author} ; Vania D. Miller^a ; Melissa M. Hadley^a ; Jessica S. Jewell^a ; Evangeline Macadat^a
• 关键词：AO ; Attentional Set Shifting Only ; ATSET ; Attentional Set Shifting ; BMO ; Barnes Maze only ; CD ; Compound discrimination ; CompRate ; Completion rate ; DA ; Dual-assay ; ESL ; Escape latency ; FF ; Food Foraging ; GABA ; gamma-aminobutyric acid ; HZE ; High Z and Charge ; IDR ; Intra-dimensional shift reversal ; PFC ; Prefrontal Cortex ; PRA ; Probabilistic Risk Assessment ; REL ; Relative Escape Latency ; RRP ; Readily Releasable Pool
• 刊名：Life Sciences in Space Research
• 出版年：2016
• 出版时间：August 2016
• 年：2016
• 卷：10
• 期：Complete
• 页码：17-22
• 全文大小：515 K

文摘

NASA is currently conducting ground based experiments to determine whether the radiation environment that astronauts will encounter on deep space missions will have an impact on their long-term health and their ability to complete the various tasks during the mission. Emerging data suggest that exposure of rodents to mission-relevant HZE radiation doses does result in the impairment of various neurocognitive processes. An essential part of mission planning is a probabilistic risk assessment process that takes into account the likely incidence and severity of a problem. To date few studies have reported the impact of space radiation in a format that is amenable to PRA, and those that have only reported data for a single cognitive process. This study has established the ability of individual male Wistar rats to conduct a hippocampus-dependent (spatial memory) task and a cortex-dependent (attentional set shifting task) 90 days after exposure to 20 cGy 1 GeV/n ⁵⁶Fe particles. Radiation-induced impairment of performance in one cognitive domain was not consistently associated with impaired performance in the other domain. Thus sole reliance upon a single measure of cognitive performance may substantially under-estimate the risk of cognitive impairment, and ultimately it may be necessary to establish the likelihood that mission-relevant HZE doses will impair performance in the three or four cognitive domains that NASA considers to be most critical for mission success, and build a PRA using the composite data from such studies.