Why do we feel nostalgia?

Why do we feel nostalgia?

Laura Riggall and Shail Bhatt investigate how we generate the feeling of nostalgia, what triggers it, and the purposes it may serve.

Don’t you wish you could just live in the past, to forever revel in the memories that act as a reminder of the comforts of childhood, to live in those days that were filled with joy and devoid of worry, and shield yourself from the harsh unknowns and realities of tomorrow?

Think about it; you probably have. Those memories of playing in the local park, of rushing home to catch after-school television (Raven, Buffy the Vampire Slayer and Cartoon Network, anyone?), those wonderful moments playing outside with friends on a hot summer’s day, of holidays abroad and days by the seaside.

Revisiting such memories derived from one’s childhood will almost certainly trigger some yearning for the past. In the 17th century, such longings were considered a mental disorder, a pathology conceived by the Swiss physician Johannes Hofer when attempting to understand the desire of soldiers to return home. Unable to understand such inclination, he called these yearnings ‘nostalgia’.

A source of intrigue, nostalgia has also been documented in great literary works. Marcel Proust, considered one of the most influential authors of the 20th century, penned the regarded novel À la recherche du temps perdu (‘In Search of Lost Time’). This work introduced ‘streams of consciousness’: the process of writing in great detail what is both perceived and remembered via perception and memory. Famously, Proust’s narrator revels in a journey of memories when he tastes a madeleine dipped in tea.

Now, society views this yearning as a form of comfort to take refuge in, and is very much a part of human nature. According to Alan R. Hirsch in his report, Nostalgia: A Neuropsychiatric Understanding, nostalgia is “a longing for a sanitized impression of the past, what in psychoanalysis is referred to as a screen memory; not a true recreation of the past, but rather a combination of many different memories, all integrated together, and in the process all negative emotions filtered out”.

Often, the childhood comforts taken for granted return during stressful periods, such as the turbulent years of adolescence. Only moments of happiness are recalled, and feelings of sadness or pain are not. However, as Hirsh points out, nostalgia isn’t just the process of recalling a memory, but rather an emotional state which is attached to a specific time or event.

Everyone has in some capacity experienced nostalgia. But what triggers it? Nostalgia can be induced by a number of stimuli. In 1908, Freud recognised a significant connection between odours and emotions, the former now considered to elicit the strongest feelings of nostalgia. The average person can detect around 10,000 different odours, each of which will cause a personalised reaction as a smell is associated with a certain experience. But why?

The olfactory lobe, found in the forebrain, is connected directly to the limbic system, which houses both the amygdala (the root of intense emotions and motivation) and the hippocampus (whose function includes memory formation). Thus, nostalgia is commonly triggered by odours. Interestingly, the smell of baked goods was found to be the greatest olfactory stimuli of nostalgia.

Imaging studies have since provided greater detail of the involvement of memory and reward systems, and have deciphered how these complex pathways collaborate to generate nostalgia. In a study conducted in 2016 by researchers residing in institutions across Japan, functional MRI, to image brain activity as participants were shown childhood-related visual stimuli, revealed significant co-activation of the hippocampus and striatum (part of both motor and reward systems).

Not only did the degree of activation correlate with individual ‘nostalgia tendencies’, these researchers also concluded that two dimensions underlie nostalgia: emotional and personal significance, and chronological remoteness, with both correlating to different areas of activation.

Other stimuli, such as music, can also cause nostalgia. Playing a song from a certain generation’s youth can excite individuals born in that generation; an otherwise forgettable song can transport someone back in time, because that particular song can remind them of being 12 years old when that same song was repeatedly played on the radio.

Interestingly, musical preferences can be inherited. In 2012, researchers at Cornell University and UC Santa Cruz revealed that 20-year-olds felt nostalgia, not only due to music played during their own childhood, but also to music from the 1960s and 1980s. It is likely that parents pass down their musical tastes to their children by playing the same songs frequently during their child’s developmental years.

Scientists have also used MRI to study nostalgia in participants viewing pictures of places carrying emotional significance for them. The study, conducted by researchers at the National Trust and the University of Surrey, showed a far greater boost of activity in the amygdala when volunteers were shown pictures of meaningful places, compared to important objects. It suggests, for example, that the place where a person gets married carries a far greater emotional importance than the ring they receive.

While nostalgia might seem to be all about taking a trip down memory lane for one’s enjoyment, it has both physiological and psychological functions, and has an evolutionary role to play.

Research conducted by Xinyue Zhou at the Sun Yat-Sen University, China, shows that nostalgia maintains a “physiological comfort”. Nostalgia is triggered by colder temperatures, and, surprisingly, has a role in maintaining body temperature. By conducting research on ninety undergraduate students, the study revealed that participants felt more wistful on colder days, and that nostalgia can actually create the notion of physical warmth.

Another large study conducted at the University of California, which enrolled over a thousand participants, showed that music-evoked nostalgia increased the degree of physical warmth felt. A similar experiment demonstrated how nostalgia alleviates the internal feeling of discomfort and pain, which further underscores the evolutionary advantage of nostalgia. It seems, then, that nostalgia serves a much greater purpose in our lives than we initially thought.

Nostalgia has also been shown to have several effects on human mood and behaviour. The primary psychological triggers of nostalgia were revealed, by Tim Wildschut and Constantine Sedikides at the University of Southampton, to be loneliness and negative emotions. Their study of 70 students proved a causal relationship between bad moods and the evoking of nostalgic memories.

These results seem quite intuitive; when we are upset, we may think of positive moments from our past. Doing so actually has a ‘healing effect’ of sorts, as nostalgia has been linked to optimism. A series of four research experiments conducted by Wildschut, Sedikides, and Wing Yee Cheung established clear relationships between nostalgia and positivity: study 1 showed that nostalgic memories are usually positive, study 2 highlighted the fact that nostalgia boosts cheerfulness, study 3 established a connection between nostalgia and higher levels of self-esteem, and study 4 demonstrated that nostalgia facilitates greater social connection, and hence boosts optimism.

The connection between creativity and nostalgia has also been closely examined. The experiments, formulated by Wijnand van Tilburg from the University of Limerick, clearly showed that nostalgia increased creativity. Here, 175 undergraduate students from the university were placed into two groups; one group was asked to recall a nostalgic event from their past, while the other was asked to think of an ordinary event. Both groups were then asked to write a story containing certain keywords (like ‘princess’ and ‘race car’).

By using a scientific index to assess creativity, researchers were able to see that the students who thought about nostalgic memories had a higher creativity score than those that thought about everyday situations. Thus, it seems that nostalgia helps to lift spirits and keep us afloat in times of bleakness. But nostalgia is much more than that. In fact, it probably helps society function more smoothly.

Moreover, nostalgia creates a sense of social connection, and in further research carried out by Zhou, nostalgia was shown to enhance empathy towards strangers and promote charitable intentions. Using a simulation of a non-profit organisation, participants asked to recall a nostalgic memory were more likely to donate and volunteer more, compared to those that were asked to recall an ordinary event from their past week.

Overall, perhaps once considered an unhealthy habit of comparing how things used to be to how they are now, nostalgia can instead provide great benefits, such as a sense of happiness and optimism. Therefore, if we all lived in the past more, the future would perhaps be brighter.