A lot of things are known to shrivel up in cold conditions. Particularly human extremities like toes and fingers. But brains may also experience shrinkage, at least according to a study published this week in The New England Journal of Medicine.
For their research, U.S. and German scientists monitored nine people who spent 14 months at a lonesome research station in the South Pole. At the end of that sojourn, the subjects were found to be literally light-headed. Before-and-after scans of their brains revealed that certain structures had significantly shrunk. In particular, the hippocampus — the cerebral cog critical for learning and memory — slimmed down substantially.
But scientists suggest it's not so much the cold that shrinks brains, but rather loneliness and isolation. While living and working at the Antarctic station with sparse company, the test subjects didn't get much in the way of stimulation.
We know that loneliness does a number on our health. Some experts suggest it's as toxic as smoking 15 cigarettes a day. But this study suggests the brain actually starts shedding weight — bits of itself that are critical to socialization — as it gets lonelier.
Even worse, it seems the brain has a hard time coming back from that experience. As the researchers explain to LiveScience, a brain that sheds weight from the hippocampus loses some of its ability to process emotions and interact with others.
For one of their tests, researchers measured the amount of protein called brain-derived neurotrophic factor, or BDNF. The brain relies on that protein to mint new neurons and create neural connections. In all nine of the test subjects, BDNF markedly declined as their Antarctic experience wore on.
Compared to a healthy control group — nine people who didn't wile away months in the Antarctic — the polar-bound participants showed a notable decline in both brain volume and BDNF protein.
A lonely brain only gets lonelier, as it's essentially losing the ability to forge new bonds. It seems a polar ice sheet — even if it's just one of the mind — is a terrible place to live.
As the new research suggests, it's not the cold, but rather the monotony that feasts on a brain. A brain that slogs through the same routine every day, while seeing the same faces over and over again, has trouble forging new meaningful connections and experiences.
And that's a problem in a society that's experiencing an epidemic of loneliness.
"Being connected to others socially is widely considered a fundamental human need — crucial to both well-being and survival," psychology professor Julianne Holt-Lunstad noted in a press release related to another study. "Yet an increasing portion of the U.S. population now experiences isolation regularly."
But there is hope. The research team focused on ways to fortify the mind against shrinkage — things like "specific physical exercise routines and virtual reality to augment sensory stimulation," as they tell LiveScience.
Or, of course, you could also try not spending too long at an Antarctic research station. Or even better, avoid making an Antarctic research station out of your life here in civilization.
Either way, it makes sense to try to make some new friends.