Cognitive effects of low dose of ionizing radiation – Lessons learned and research gaps from epidemiological and biological studies

International audienceThe last decades have seen increased concern about the possible effects of low tomoderate doses of ionizing radiation exposure on cognitive functions.An interdisciplinary group of experts (biologist, epidemiologist, dosimetrists andclinicians) in this field gathered together in the framework of the European MELODIworkshop on Non-Cancer Effects to summarise the state of knowledge on the topic andelaborate research recommendations for future studies in this area.Overall, there is evidence of cognitive effects from low IR doses both from biology andepidemiology, though a better characterization of effects and understanding ofmechanisms is needed.There is a need to better describe the specific cognitive function or diseases that may beaffected by radiation exposure. Such cognitive deficit characterization, should take intoaccount the human life span, as effects might differ with age at exposure and at outcomeassessment.Measurements of biomarkers (including imaging) will likely help our understanding onthe mechanism of such cognitive-related radiation induced deficit and, individualsusceptibility may be better elucidated with a genetic analysis.The mechanisms behind the radiation induced cognitive effects are not clear, and arelikely to involve several biological pathways and different cells types.The understanding of radiation-induced cognitive effects will benefit of well conductedresearch in large epidemiological cohorts and experimental studies in animal models.Such results will likely inform the clinical decision making process