Just a few months of life in Antarctica can be brain-shrinkingly tough. Scientists have recently studied the brains of nine people (five men and four women) before and after they spent 14 months working at the German research station Neumayer III in Antarctica.

Reported in the journal The New England Journal of Medicine, MRI scans taken after their expedition showed that the nine crew members had lost a significant amount of volume in their dentate gyrus, the part of the brain’s hippocampus associated with spatial thinking and memory. They also detected less gray-matter volume in parts of the prefrontal cortex, the brain region implicated in personality, decision making, and social behavior.

The brain changes also appeared to have an effect on their cognitive abilities. Tests showed that the participants had reduced spatial memory and selective attention, the ability to ignore irrelevant information when focusing on a task.

Life in the South Pole – an environment often subject to periods of 24-hour darkness and an unchanging snowy backdrop – is harsh for a social creature. Not only must workers face temperatures as low as -50°C (-58°F), but they may also experience a sense of chronic cabin fever. Everyday life inside the research station is characterized by monotony and prolonged social isolation while offering little in the way of privacy or stimulation.

While they didn't specifically search for a causal link, the researchers believe the changes in the brain they observed are the result of this environmental monotony and prolonged isolation. After all, previous studies have suggested that social isolation can have a profound effect on both behavior and the structure of the brain. Whether these findings can be applied directly to human brains is hard to say, but the new study certainly hints at a link between our social environment and our brain.

“This scenario offers us the opportunity to study the ways in which exposure to extreme conditions affect the human brain,” study lead Alexander Stahn, from Charité’s Institute of Physiology and assistant professor at the Perelman School of Medicine at the University of Pennsylvania, said in a statement.

“Given the small number of participants, the results of our study should be viewed with caution,” cautioned Alexander Stahn, adding: “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.”