(CNN) Darkness covers the Norwegian city of Tromsø from late November through January, a long, polar night when the sun never rises at all. The island community, which is more than 200 miles north of the Arctic Circle, is flanked by snowy peaks and frigid water. Northern lights flicker in the sky there.
"If winter were a place, it would be Tromsø," said Kari Leibowitz, a doctoral student of psychology at Stanford University, who spent a year there for her graduate research. Leibowitz arrived in the Arctic city hoping to study seasonal affective disorder, the seasonal depression that some experience in the darkest time of year.
This condition is a big problem. Prevalence of seasonal depression in North America increases with latitude; in New Hampshire, nearly 10% of the population is estimated to suffer from SAD. And while New Hampshire's northernmost town sits at 45 degrees north, Tromsø is at 69 degrees north — the Norwegian city is much, much closer to the North Pole. Everything Leibowitz learned as a psychology undergraduate suggested Tromsø would be ground zero for SAD.
"When winter gets more extreme, you should have a higher prevalence of seasonal affective disorder, and you should have worse seasonal affective disorder," Leibowitz said. But after Leibowitz arrived, her Norwegian graduate adviser explained that in Tromsø, mental health and well-being actually remain pretty stable through the winter.
Abruptly, Leibowitz's question changed. "What is it that allows people living in this Arctic city, where the sun doesn't rise for two months ... to thrive?" she asked. Her findings, published in a recent paper for the International Journal of Wellbeing, offer hope for those who dread the season's first snowfall.
Her research suggests that SAD isn't just about the dark and cold weather, but something Leibowitz calls "wintertime mindset," an individual's ideas and beliefs about the season.
Good or bad, we all have a mindset about winter — and what we believe seems to inform our mental health. In Tromsø, where many respondents in Leibowitz's research expressed positive associations with winter, seasonal depression isn't so bad.
It's more important than ever to address your "I hate being outside in winter" dread, since the pandemic shows no signs of abating and playing 6 feet apart outside with others is much safer than playing inside in winter. And masks make sense when you're having fun outside in the cold weather, since they can keep you warm (and safer).
If you are a dedicated winter hater, though, it doesn't mean you're doomed to a lifetime of winter blues. The good news, Leibowitz said, is that mindset can be surprisingly flexible.
If you want to change your perspective, Leibowitz said an initial step is to take a close look at what you already believe. "Shifting your mindset comes from first examining your mindset," she said. "Think to yourself: 'All right, what do I think of when I think about winter?'"
For some, imagining winter evokes a long list of frustrations and hassles: Shoveling snow, icy sidewalks, heavy clothing and overcast skies are common gripes. But if that's all that comes to mind, it's a sign you could benefit from overhauling your perspective.
"There's a lot of evidence that mindset can be changed, but it often takes this kind of deliberate intervention," Leibowitz said. There's no one-size-fits-all solution for doing that. Instead, Leibowitz suggested you sit down to list the things you enjoy about winter.
For Leibowitz, a self-described indoors type, the list of wintertime joys includes getting cozy with a book and streaming movies. In Tromsø, she loved cafes that used twinkling lights and candles to create an inviting atmosphere. Cultures across the globe celebrate holidays in the winter, traditions that bring special foods and rituals.
Out of doors, you'll find wintry joys that are just as fleeting as summer heat. A "winter happiness" list might feature the smell of fresh snow, or the sound of trees crackling in the cold.
Midwinter is a time to gather around outdoor bonfires and discover ice formations, too.
And while winter can be a time of great stillness, every day brings small transformations in the natural world — just looking out a window at snowy streets or bare-branched trees is part of the experience.
In her social psychology research, Leibowitz studied the phenomena of SAD across a whole community. But her findings mirror research by psychologist Kelly Rohan, a professor at the University of Vermont who has been running clinical trials on SAD for two decades. With a lab in chilly Burlington, Vermont, she works with participants who face months of extreme cold, snow and darkness.
Rohan in recent years has contrasted the two primary treatments for seasonal depression. The first is light therapy, which uses exposure to powerful artificial lights to mimic the sunshine we get in warmer months. Another approach is cognitive behavioral therapy, talk therapy focused on changing beliefs and behaviors.
Side-by-side comparisons show that in the first year of treatment, light therapy and CBT are about even in their effectiveness. "If it were a horse race, it would be a dead heat," Rohan said. But differences emerged in the second year.
"When we follow people after treatment is over for a second year, we have observed better outcomes following CBT relative to light therapy," Rohan said. "Less severe symptoms in the winter, and fewer of what we call 'recurrences'... the full-blown return of symptoms in the future."
In CBT for seasonal depression, Rohan uses a "seasonal beliefs questionnaire," which asks participants to rate their agreement with a series of statements, including "dark, gloomy days are depressing," and "I'm stuck in a rut in the winter."
Part of her methodology for CBT is to question those beliefs. "We say: 'What's the evidence for that? Is there any other way to think of that?'" she explained. "We reframe that thought so it's a little less extreme, so it would have a little less effect on your mood."
The goal isn't to get participants to love winter. Rather, Rohan's approach is designed the create some mental flexibility, leaving room for slightly different beliefs about the season.
In many ways, the "cognitive" part of cognitive behavior therapy aligns with the mindset that Leibowitz studies — and Rohan's research offers a blueprint for how those facing SAD can experience lasting change.
Of course, the Norwegians who Leibowitz met in her year living in Tromsø don't just sit inside thinking about winter. The country is famously outdoorsy.
"People are sort of out and about, dressed up and enjoying winter," Leibowitz said. Her adviser and co-author on the study, Joar Vittersø, a professor of social psychology at the University of Tromsø, would sometimes commute to the university on cross-country skis. And even if you don't live in a place where roads turn into ski trails, getting outside can be a mood reset.
You've probably heard it before: Contact with the natural world has broad benefits for mental health, a finding that's supported by study after study. People who get 120 minutes of nature time in each week are healthier and happier.
Getting outside is generally a really good idea.
But while CBT treatments for seasonal depression do attempt to change your habits — that's the "behavior" part of CBT — Rohan said getting outside isn't a strict requirement for improving your mental health. "If you like being outside, then yes," she said, go out and play in the snow.
Just remember, if you hate being outside in the winter because it's cold, the right clothes and boots may address that issue.
Otherwise, do what makes you happy. "There are plenty of ways to engage with other people and enjoy life that are indoor activities in the winter," she said. Amid a viral pandemic where transmission is far higher indoors, that's challenging, but you can still write a postcard, send a care package or schedule a regular video chat date.
For those who truly hate the cold, Rohan said that forcing yourself to be outside could have the opposite of the intended effect. When it comes to overturning the "hibernating" patterns of behavior that come with seasonal depression and keep you glued to the couch, those indoors activities help, too.
That means this winter, with the pandemic disrupting many in-person activities, you should simply do what works. Rohan explained that the important part is staying engaged: Go for a walk, watch birds, take an online class, call a loved one, join a virtual book club or do any other safe thing that you like.
"Anything that gets (you) out of hibernation mode is the proactive behavior we want to get people on, regardless of whether it's inside or outside," Rohan said.
Referrals to mental health services in your area are available — in Spanish and English — from the Substance Abuse and Mental Health Services Administration (SAMHSA) hotline: 1-800-662-HELP.