The effects of high-energy protons and carbon ions (12C) on the cognitive function and the content of monoamines and their metabolites in peripheral blood in monkeys

Model experiments using monkeys (rhesus macaque monkeys) were performed to investigate the neurobiological effects of two components of galactic cosmic radiation, namely, high-energy protons and carbon ( 12 C) ions. It has been demonstrated that the irradiation of a monkey’s head with protons at a dose of 3 Gy did not cause any significant changes in the animal’s cognitive function and in the concentrations of monoamines and their metabolites in the peripheral blood. However, exposure to carbon ions at a dose of 1 Gy resulted in a significant cognitive function impairment and a significant decrease in serotonin metabolite concentrations in the blood in the monkeys with the excitable imbalanced type of higher nervous activity.