One of my most pleasant early memories was of my sister, Chris, and I going to an amusement park when I was in nursery school. I couldn’t remember the excursion because I had been so young when we went, but my sister regaled me with colorful tales that made the experience vivid in my head. I loved hearing about our rides on the roller coaster and Ferris wheel, and how we screeched when “ghosts” popped out of nowhere as we walked through the Haunted House. I could almost hear the calliope music and taste the cotton candy as she described them to me. Thinking about that special day sent a wave of good feeling washing over me.

I had discovered nostalgia.

Nostalgia Finally Gets Credit for Its Psychological Value

The term nostalgia was coined in 1688 by Scottish physician Johannes Hofer to describe the physical and mental problems of soldiers who longed to return home. Hofer referred to it as “a neurological disease of essentially demonic cause.” That’s right: nostalgia was long considered a state of dysfunction. In later centuries it was often referred to as an “immigrant psychosis,” a condition suffered by those who had moved to a new country and missed the land of their roots.

Although nostalgia is clearly associated with sadness and regret over golden moments long gone, its reassessment in recent years has led to recognition of its positive benefits. A key figure in celebrating the value of nostalgia is Constantine Sedikides, Ph.D., a professor of social and personality psychology at the University of Southampton, England. Dr. Sedikides began seriously investigating nostalgia after experiencing a wave of it himself following his relocation to England from the University of North Carolina in 1999. Today there are dozens of nostalgia researchers worldwide, many of whom use a questionnaire called the Southampton Nostalgia Scale that was developed by Dr. Sedikides and his colleagues.

Nostalgia has been found to be a valuable coping tool for dealing with loneliness, boredom, and anxiety. It can even help increase one’s comfort in physically unpleasant situations. “It makes people more generous to strangers and more tolerant of outsiders,” wrote John Tierney about nostalgia in the New York Times. “Couples feel closer and look happier when they’re sharing nostalgic memories. On cold days, or in cold rooms, people use nostalgia to literally feel warmer.”

Studies reported in the Scientific American by social psychologist Dr. Clay Routledge show that feelings of disconnection from others often trigger nostalgia. Some study subjects were given reading material that was meant to induce a positive mood or was neutral in content, while others read material designed to trigger negative feelings such as loneliness or insignificance. Those who read passages with the negative slant were much more likely to report feeling nostalgic. This demonstrates that nostalgia “allows people to use experience from the past to help cope with the challenges in the present,” claims Dr. Routledge.

Nostalgic memories tend to involve social activities, among them family vacations, road trips with friends, weddings, graduations, birthday parties, and holiday gatherings. Most people have feelings of nostalgia every few days. And nostalgia doesn’t require a high level of mental sophistication—it can occur in children as young as seven, as it did with me.

While nostalgic memories can be bittersweet and engender feelings of regret and irretrievable loss, they skew toward the positive overall. “Nostalgic stories often start badly, with some kind of problem, but then they tend to end well, thanks to help from someone close to you,” said Dr. Sedikides, as reported in the New York Times. “So you end up with a stronger feeling of belonging and affiliation, and you become more generous toward others.”

Of course, overdoing nostalgia is hardly a healthy activity, especially since we may rewrite our personal histories to take out the rough edges. Thus we may miss the opportunity to learn lessons from failures of the past that could help us avoid mistakes in the present, or we mistakenly assume that our lives today can never be as good as the “good old days.”

Spoiler Alert: Why I Couldn’t Remember Going to the Amusement Park

Turns out there was another reason why I had trouble recalling that wonderful pre-school wonderful outing with my sister…It never happened.

After I requested yet again to be regaled with stories from that day, my sister blurted out that she had made it all up. At first I thought she was messing with me, but then I consulted the most reliable source in the universe: Mom. My mother confirmed that no such excursion had taken place.

I was, of course, shattered by hearing that my beloved memory was a sham. But as I proceeded into the future, the pleasure of that ersatz experience was somehow sustained. I continued to feel that my sister and I had shared something important. It made me feel closer to her, as if mooring us together in a piece of treasured common history.

It was the mysterious power of nostalgia.

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