Have you ever listened to a song that you hadn’t heard for years and had the feeling of having returned, for a few moments, to another moment of your life? A holiday, school, an evening with friends, a person you haven’t seen for a while.
First smile. Then comes a different feeling: a bit of melancholy, perhaps the desire to go back. It’s the paradox of nostalgia: it can make us feel good and bad at the same time. In psychology it is described as an emotion bittersweetthat is, bittersweet: capable of making us experience pleasant feelings, such as happiness, affection and connection, but it also brings with it a shade of sadness, linked to the awareness that what we remember now belongs to the past.
Several studies have concluded that nostalgic memories tend to concern significant experiences in our lives, while research published in 2026 showed an important presence of memories related to childhood, through photographs, music, smells, conversations and food.
What it means to feel nostalgia and the difference with memory: it is not remembering
First of all, nostalgia and memory are not the same thing. We can remember what we did yesterday, a phone number, a professor’s name, or specific dates without necessarily feeling nostalgic. This emotion, in fact, appears when an autobiographical memory takes on a particular emotional and personal value.
Studies show that nostalgic memories tend to concern significant experiences in our lives and very often involve other people: friends, family, partners, classmates. It’s not just an episode from the past that resurfaces: the emotions we felt and the meaning that that experience had for us return with it. An old photograph, for example, can do much more than show us an image: it can take us back to a place, to the people who were there with us, to an earlier version of ourselves and what that moment represented. Nostalgia, therefore, is not simply remembering the past: it is feeling, in the present, emotions towards something that belongs to our history and that we can no longer experience in the same way.
Why does it make us feel good?
In scientific literature, there are mainly three reasons that associate nostalgia with a state of well-being:
- The relationships. Many nostalgic recollections concern the social sphere: thinking back to an evening with friends, a trip with the family or an important relationship can mentally reactivate the sense of closeness and belonging associated with those experiences.
- It can increase the sense of continuity of our identity. Even if we have changed over time, finding elements of ourselves in past experiences can make us feel greater stability and personal coherence. In practice, it helps us perceive our life not as a sequence of disconnected versions of ourselves, but as a story in which past experiences have helped build who we are today.
- Strengthens the perception of the meaning of one’s life. Recognizing that our life has contained moments and relationships to which we attribute value can make us perceive our existence as more meaningful, contributing to well-being.
How nostalgia can make us feel bad: scientific studies
However, nostalgia also has a “bitter” component. In fact, when we return our mind to something significant, we can become more aware of the distance between that past and our present.
- It reminds us of what we have lost. A person who is no longer part of our life, a friendship that has ended, a place that we no longer frequent or simply a period that has ended: the memory can bring to mind something that we no longer have today.
- It makes us aware of change. Not only has everything around us changed: we have changed too. Thinking back to an old experience can highlight the distance between who we were then and who we are today.
- It can bring out what we are missing in the present. If we feel alone today or are going through a difficult time, a positive memory can make the contrast with our current state more evident.
In any case, nostalgia is not always “sweet” or “bitter” to the same extent: its value can also depend on what is happening in our present. This conclusion was reached by David B. Newman and Matthew E. Sachs in 2023, in their study Variation in Bittersweet Nostalgic Feelings and Their Divergent Effects on Daily Well-Beingin which they followed 151 people for 14 days, collecting 1,356 daily reports. Positive events experienced during the day tended to be associated with more pleasant nostalgic feelings, while negative ones with more painful feelings.
But what does it mean concretely? Let’s imagine thinking back to an old holiday with friends. If that very day we spent a pleasant evening with people to whom we are still close, the memory could bring back above all the pleasure of that relationship and the feeling of closeness. If, however, we feel alone or have just experienced a negative situation, the same memory of the holiday could bring out the distance from that period or from those people more. The memory, therefore, is the same, but it can change the way we experience it.
This is one of the most interesting aspects of nostalgia: it doesn’t just concern what we remember, but also the moment in our lives in which we do so.
Which memories arouse the most nostalgia? And what are the triggers that evoke it?
One of the first systematic studies on nostalgia, conducted in 2006 by T. Wildschut and colleagues, analyzed people’s autobiographical narratives by asking them to describe a nostalgic experience. Among the most frequent elements appeared people and important events in one’s life: relationships, friendships, family and shared moments, rather than simple objects or places. This result suggests that it is not necessarily the things themselves that are nostalgic; an old photograph is not nostalgic because it is a photograph: it becomes nostalgic because it connects us to a person, an experience or a part of our history.
Recent research published in 2026 explored the question even more directly: participants were simply asked what made them feel nostalgic. Photographs, music, smells, conversations and food frequently appeared among the responses. The study involved 256 participants and also showed an important presence of memories related to childhood.
But what triggers a nostalgic memory? In fact, it is not necessary to encounter something that belongs to the past. In the aforementioned study by T. Wildschut, the most frequently reported trigger was in fact a negative emotional state, present in 38% of the stories.
This was followed by social interactions with 24%, sensory stimuli (19%), concrete objects, 9%, events similar to those remembered, 3%, free time or inactivity, 3%, positive emotions, 3%, anniversaries, 2%, places or settings, 1%. It should be noted that the categories are not mutually exclusive (the same description could fit into more than one) therefore the percentages do not add up to 100.
