Looking at historical photographs feeds our nostalgia and renders long-gone moments disarmingly real. Retronauting is the newfangled term for our old-fashioned affection for vintage shots—so called for its namesake photo-sharing site, says Jonathan Jones at the Guardian.
We can also read a lot, in retrospect, into old photos. A shot of Jawaharlal Nehru laughing with Lady Mountbatten just before Indian Independence recalls not only the magnitude of the events around 1947 but also the affair they apparently had. A photo of the opening ceremony in Woodstock titillates because we now know that the festival was a defining cultural moment in American history.
Can nostalgia explain why the average Millennial enjoys old photos, too? Can you pine for postwar Britain without having experienced postwar Britain? Psychologist Clay Routledge, who studies nostalgia at North Dakota State University, thinks so. He says there are two types of nostalgia: autobiographical (a fondness for your own memories) and historical (a fondness for broader cultural ones).
"There's this notion that younger generations stay connected to older generations because we pass down our nostalgia," Routledge tells Co.Design. "So I think one way this historical nostalgia works is, just like people pass down keepsakes in their family, we pass down memories."
The science of nostalgia is a relatively young one—it emerged in the last few decades. For most of modern history, nostalgia has been seen in a negative light. Physicians in the 17th and 18th centuries viewed it as a neurological disease. After that it was seen as more of a depressive and regressive state: being stuck in the past. But the evidence has made a strong pivot, with behavioral scientists now convinced that nostalgia offers psychological benefits.
This new wave of research (much of it emerging from the University of Southampton, in England) has found that nostalgia generates positive feelings, improves self-regard, and enhances our bonds with others. This heartwarming effect is not just figurative; a 2012 study showed that nostalgia produced physiological warmth. Test participants who recalled a nostalgic event perceived a room to be hotter than those who recalled a neutral memory (and kept their hands dipped in cold water longer).
Recently, Routledge and some collaborators showed that nostalgia serves an "existential function." In one study, the researchers randomly assigned some test participants to read nostalgic song lyrics, and others to read neutral lines. Those in the nostalgic group subsequently rated their lives as more meaningful and full of purpose. "Nostalgia reminds us that people love us, and that we've had good interpersonal experiences," says Routledge. "So our lives feel worthwhile."
It's little surprise, then, that feeling nostalgic for the past can make us hopeful for the future. A study published in the November 2013 issue of Personality and Social Psychology Bulletin found that test participants who recalled a nostalgic event reported feeling more optimism than those who remembered an ordinary one. Routledge, who was not part of the research team, says the finding helps explain why nostalgia, though often triggered by loneliness or sadness, is a healthy and adaptive emotion.
"When people are nostalgic, it's a coping mechanism that propels them forward," he says. "This is one way for people to use their own memory systems to mentally time travel and conjure up the evidence that life's good."
This isn't to say that every time you're feeling blue you can just scroll through vintage photos and get right in the head. Researchers are currently exploring what they call the "boundary conditions" of nostalgia—when the emotion could have a detrimental effect on certain personality types or in certain situations. Imagine someone who tilts to depression, for example, looking at a nostalgia-creating photo to reinforce the belief that things will never be as good again.
It's also important to remember, as Jonathan Jones says in the Guardian, that nostalgia and history are not one and the same. When we're nostalgic, we tend to celebrate the good old days, and forget how terrible they might have been. The charming vision of postwar life in Britain, for instance, is elevated above the harsh austerity of the times. Routledge mentions that his 12-year-old recently developed warm feelings for the '80s. Now that's a scary image.