Nostalgia may have bona fide benefits in hard times, like the pandemic

Over 300 years ago, Swiss physician Johannes Hofer observed disturbing behaviors among Swiss mercenaries fighting in far-flung lands. The soldiers were prone to anorexia, despondency and bouts of weeping. Many attempted suicide. Hofer determined that the mercenaries suffered from what he called “nostalgia,” which he concluded was “a cerebral disease of essentially demonic cause.”

Nowadays, nostalgia’s reputation is much improved. Social psychologists define the emotion — which Hofer saw as synonymous with “homesickness” — as a sentimental longing for meaningful events from one’s past. And research suggests that nostalgia can help people cope with dementia, grief and even the disorientation experienced by immigrants and refugees (SN: 3/1/21).

Nostalgia may even help people cope with the COVID-19 pandemic. In a study published September 8 in Social, Psychological and Personality Science, researchers found when some lonely, unhappy people reminisced about better, pre-pandemic moments, they felt happier. The results suggest that nostalgia can serve as an antidote to loneliness during the pandemic, the researchers conclude.

“A good analogy is the immune system,” says social psychologist Tim Wildschut of the University of Southampton in England. “A viral infection may make you ill, but it also activates your immune system and your immune system makes you better. Loneliness reduces happiness but also triggers nostalgia, and nostalgia increases happiness.”

In the new study, Wildschut and colleagues first surveyed over 3,700 participants in the United States, United Kingdom and China to assess people’s levels of loneliness, nostalgia and happiness during the early days of the pandemic. Surveys varied slightly by country, but for most questions or statements, participants responded on a scale from 1 to 7, with 1 for “not at all” and 7 for “very much.” For instance, participants in the United States rated how isolated they felt from the rest of the world in the week prior to the survey, how happy they felt compared with their peers and their overall feelings of nostalgia.

The researchers found that across the three countries, people who scored relatively high in loneliness also, not surprisingly, scored lower in happiness. But when the team drilled down on the role nostalgia plays, they found people who didn’t indulge in those memories were the least happy.

“Loneliness [triggers] unhappiness and nostalgia. Then unhappiness and nostalgia fight with each other,” says coauthor Constantine Sedikides, a social psychologist also at the University of Southampton.

Meanwhile, in three experiments with new sets of U.S. participants, the researchers manipulated people’s nostalgia levels, using the spring 2020 lockdown as a proxy for heightened loneliness. For example, in one experiment conducted in April 2020, the researchers recruited just over 200 online participants. The team induced nostalgia in half the participants by having them write four words describing a specific nostalgic event from their past. Participants were then prompted to write freely for three minutes about how that past experience made them feel. People in the control group completed the same tasks but about ordinary past experiences.

Those experiments revealed that, compared with the control group, participants in the nostalgia group reported slight but statistically significant higher happiness levels, as measured by the same 1-7 scale used in the earlier surveys. For instance, in the experiment with the 200-plus participants, the researchers found that happiness scores in the nostalgia group averaged 5.64 compared with 5.3 in the control group. Statistical analysis suggests that nostalgia can explain about 2 percent of the variation in happiness, the researchers say.

Those results may sound trivial, but even small variations can yield large results when viewed across large populations or across time, says personality psychologist Friedrich Götz of the University of British Columbia in Vancouver.

“Let’s say you are a happy person every day of your life. Chances are you will have a more fulfilled life than if you are a less happy person,” Götz says. “So 2 percent can make a difference because our happiness influences how we act, feel and think every day of our lives.”
The hope that nostalgia-induced happiness could build up over time underpins some researchers’ long-term goal of harnessing and deploying techniques to trigger nostalgic memories as a form of therapy. Nostalgia can connect people to their past, present and even desired future selves, these researchers say. And since many nostalgic memories often involve other people, they can also help people feel linked to a wider community.

In one study, for example, existential psychologist Clay Routledge and colleagues tapped nostalgia’s social side. Participants first completed an established “nostalgia inventory,” where they rated on a scale from 1 to 5 how nostalgic they felt about 20 aspects of their past lives, such as family and vacations. The researchers then asked people about the types of studies that they might want to participate in later on. Two of those potential studies involved meeting other participants while two others did not.

Participants reporting high levels of nostalgia, especially those nostalgic for social experiences, were more likely than other participants to select the studies that involved meeting new people, the researchers reported in the December 2015 Journal of Personality and Social Psychology. That suggests that proneness to remembering meaningful past social experiences engenders future social experiences, the team says.

“Nostalgia isn’t just people remembering time with loved ones,” says Routledge, of North Dakota State University in Fargo. “It’s orienting them toward building new social experiences.”

A key question, though, is if nostalgia’s benefits can persist beyond that fleeting moment of remembrance. Wildschut’s team found that nostalgia’s benefits, in terms of happiness, faded after just a day or two. But nostalgia-induced happiness persisted for a couple days when the researchers reminded people to think about that special memory.

Crucially, nostalgia therapy may not be for everyone. Researchers reported in October 2019 in Personality and Individual Differences that invoking nostalgia in individuals who viewed relationships as a source of comfort and security increased those people’s intention to engage with others. The reverse, however, held true for individuals who saw relationships as a source of pain.

“For these types of avoidant people … nostalgia pushed them in the opposite direction. They were even less likely to want to connect with others on a deeper level,” says existential and social psychologist Andrew Abeyta of Rutgers University–Camden in New Jersey.
Wildschut and colleagues found a similar result when investigating whether invoking nostalgia among Syrian refugees living in Saudi Arabia could increase self-esteem, sense of meaning in life, feelings of social belonging and optimism.

In that study, refugees in an experimental group wrote about meaningful events from their past, while refugees in a control group wrote about ordinary events. The experiment showed that triggering nostalgia in refugees high in resilience — a trait defined by a capacity to withstand and recover from adversity — resulted in more positive emotions than those reported by resilient refugees in a control group, the team concluded in the December 2019 European Journal of Social Psychology. But while inducing nostalgia in refugees low in resilience did help them feel a greater sense of continuity in life and more socially connected compared with a low-resilience control group, nostalgic memories also made them feel less optimistic about the future.

“When you push the test of nostalgia to those extremes, it’s a very, very tough test,” Wildschut says.

Caveats aside, Wildschut remains optimistic about developing some form of nostalgia therapy. He recalls a conversation with his young daughter many years ago. When he asked her how long nostalgia lasts, she replied “forever,” Wildschut says. “What she meant is that the memory is there, and you can recall it any time.” Ultimately, he and other nostalgia researchers hope to one day identify suitable candidates for nostalgia therapy and then train those people to recall special memories whenever they feel blue.

An ancient exploding comet may explain why glass litters part of Chile

Scattered across a swath of the Atacama Desert in Chile lie twisted chunks of black and green glass. How the glass ended up there, sprinkled along a 75-kilometer-long corridor, has been a mystery.

Now, analyses of space dust in the glass show that the glass probably formed when a comet, or its remnants, exploded over the desert 12,000 years ago, researchers report November 2 in Geology.

This corridor is the best evidence yet of a comet impact site on Earth, says Peter Schultz, a planetary geologist at Brown University in Providence, R.I.

There are only about 190 known impact craters on Earth (SN: 12/18/18). Falling space rocks carved out these sites, but none are known to have been created by a comet. That’s because comets, which are made of mostly ice and some rock, tend to explode before reaching the ground, a fate they share with some small asteroids. These fiery events — known as airbursts — are dramatic, generating massive amounts of heat and strong winds. But the effects are temporary and often fail to leave lasting imprints, like craters, behind.
That’s especially true in wet environments. In 1908, an airburst from an asteroid or comet over a remote part of Russia flattened trees and generated a shock wave that knocked people off their feet hundreds of kilometers away. The trees have since grown back over the site of what’s now known as the Tunguska blast, leaving just a marsh (SN: 6/5/08). “If it hadn’t been observed, no one would know it happened,” says Mark Boslough, a physicist at the University of New Mexico in Albuquerque who wasn’t involved in the new research.

The Atacama, the world’s driest desert, is better suited to preserving impact sites. And it’s full of sand — the raw material for making glass, which forms when sand is heated to high temperatures. Heat from volcanic activity is responsible for almost all of the naturally derived glass on Earth.

The desert’s glass corridor, however, is kilometers away from the closest volcano, suggesting the glass formed in a different type of heating event, such as an airburst. But radiocarbon dating of ancient plants in the soil around the glass seemed to indicate that the pieces didn’t all form at the same time. Because airbursts rarely occur in the same place twice, the evidence led some researchers to suggest that the glass formed during several massive grass fires.

That idea, Schultz says, “seemed really weird to us because there just wasn’t enough grass for fires,” even long ago when the area probably had more greenery than it does today. After examining some of the glass, he and colleagues determined that it had formed at temperatures exceeding 1700° Celsius — much hotter than grass fires.

What’s more, the team discovered embedded within the glass compounds found in comets sampled during NASA’s Stardust mission but almost never in asteroids (SN: 1/7/04). The only way for this space dust to have made its way into the glass is if a very old chunk of space debris, such as a comet, exploded at the moment that the glass formed, the researchers say.
Strong winds from an ancient comet’s explosion folded glass as it formed in what’s now the Atacama Desert, a study finds. Folds in the glass are visible in a microscope image (left) of a section from a larger chunk of glass (right). The yellow dot marks where the section was taken.
SCOTT HARRIS/FERNBANK SCIENCE CENTER
“It’s pretty clear that this is an impact,” Boslough says. “And in this case, there’s no evidence for a crater, so this event was a pure airburst.”

An airburst would also help explain why the glass appears twisted. “It was clear the glass had been thrown around and rolled. It was basically kneaded like bread,” Schultz says. Grass fires may melt the ground, but they rarely fling it around. Like Tunguska, the airburst probably generated strong winds that flung the glass as it formed, creating the folded look.

The violence of the impact would have scattered glass far across the desert and onto different layers of sediment. Because those layers formed at different times, that may have created the illusion that the glass was created during multiple events. Looking at the dating of plants that came in direct contact with the glass allowed the researchers to pin down the date of the probable comet strike to about 12,000 years ago.

That timing places the event about 800 years after a mysterious period of rapid cooling known as the Younger Dryas, which coincided with the extinction of many large animals. Some scientists have suggested that a comet exploding over the Northern Hemisphere set off a series of events that led to the frigid conditions, though the idea is controversial (SN: 6/26/18).

The timing of the Atacama comet strike shows that it wasn’t related to the Younger Dryas event, Schultz says, but the finding does lay the groundwork for identifying other potential comet sites on Earth.

Even without a link to the Younger Dryas, the Atacama impact would have left a strong impression on anyone who saw it. Archaeological evidence suggests that people lived in the area at the time and thus may have witnessed the airburst (SN: 11/30/15). “It would have seemed like the entire horizon was on fire,” Schultz says. “If you weren’t religious before, you would be after.”