BRAIN IN SPACE. HOW DOES SPACE AFFECT THE HUMAN BRAIN?

Abstract

Introduction Nowadays more and more people and international companies are interested in Human Spaceflights. Aim and method In this review, the negative effects from space radiation, microgravity and the factor of isolation on the central nervous system will be described in relation to space neuroscience and the relevant studies examined. Results Space radiation can damage neuronal connections with both acute and chronic effects, manifested as altered cognitive function, reduced motor function, and behavioral changes. Moreover, some astronauts report a condition known as Spaceflight Associated Neuro-ocular Syndrome (SANS). The brain scans performed upon those astronauts, who came back from space travel suggest that due to reduced gravity conditions the brain and the fluids in the human body shift upwards, which increases pressure in the skull and may result in opticnerve swelling that causes blurred vision. Another interesting part of space neuroscience is the research of structural neuroplasticity. A study conducted on cosmonauts revealed an increase in the neuronal tissue of sensorimotor structures responsible for movement coordination. In addition to the space radiation and microgravity, long-term confinement also affects the microstructure of the brain white matter, which was proven in the study that used DTI (Diffusion Tensor Imaging). Conclusions To conclude, to continue understanding the risks posed by spaceflight to astronauts’ health research in the field of space neuroscience is important. In addition, the acquired insight could be relevant for terrestrial vestibular patients, patients with neurodegenerative disorders, as well as the elderly population, coping with neurological deficits. Keywords: space medicine, brain, space neuroscience, SANS, space radiation.