Scientists had suspected for some time that living in extreme environmental conditions- such as in harsh climates and in social isolation- may have adverse effects on the brain. Now, for the first time, researchers from Charité - Universitätsmedizin Berlin and the Max Planck Institute for Human Development have had the chance to measure the cognitive effects of living in Antarctica for 14 months.

In total, five men and four women volunteered to participate in the study. Living at the Antarctic research station, they faced temperatures as low as -50 degrees celsius and almost complete darkness during the winter months. They had little privacy or personal space throughout, limited contact with the outside world and no option to cut their stay short- especially during the winter months. Emergency evacuation and deliveries of food and equipment were only possible during the relatively short summer.

Both before and after their mission, each of the participants completed an array of computer-based cognitive tests measuring for concentration, memory, cognitive reaction time and spatial thinking. Alongside this, they underwent regular blood tests to measure levels of brain-derived neurotrophic factor (BDNF), a protein that promotes the growth of nerve cells and synapses in the brain. Each participant also underwent magnetic resonance imaging to capture changes to their brain structure- focusing particularly on brain volume and the hippocampus- before and after their stay in the Antarctic.

In the end, the researchers found that the dentate gyrus of the participants, an area of the hippocampus used for spatial thinking and forming memories, was significantly smaller than those in the control group. Their BDNF levels also decreased, and did not return to normal levels even after a month and a half after the mission. Furthermore, cognitive tests showed that both spatial abilities and “selective attention” abilities, used to filter out irrelevant information, had declined.

Lead author of the study, Dr. Alexander Stahn, said “Given the small number of participants, the results of our study should be viewed with caution...They do, however, provide important information, namely - and this is supported by initial findings in mice - that extreme environmental conditions can have an adverse effect on the brain and, in particular, the production of new nerve cells in the hippocampal dentate gyrus.”

Sources: EurekAlert and The New England Journal of Medicine