Do you remember the time? How collective nostalgia inspires group loyalty

Nostalgia seems like a distraction in a world that's moving forward. But new research proposes a powerful function of the emotion: as a glue to bind members of social groups.

Students from the University of Southampton recalled and wrote about an experience either involving other students, or where they were alone. They were either asked to choose an ordinary event or one that triggered nostalgic feeling, defined in the instructions as "sentimental longing for the past".

Next they were asked how many hours they would be prepared to invest in a publicity campaign for the university. Most willing to help were those who had recalled a nostalgic memory involving other students, because (according to a post-study survey) it made them  prize their student identity more highly.

Could these intentions just be the result of a better mood? Unlikely; although textual analysis showed the nostalgic memory descriptions were more positive, across all conditions positivity was no indicator of intention to volunteer. Moreover, another experiment showed that recalling a collective "fortunate event" did not lead to more good intentions towards other students, even though these memories were very positive. Lead author Tim Wildschut points out that nostalgia is distinctive in part because it blends both positive and wistful features, and that it is this longing that makes it a more active emotion than amusement or satisfaction, inspiring people to want to revisit or protect the things that trigger it.

Nostalgia alters how people say they will behave, but is that just talk? A follow-up experiment indicated otherwise. After a nostalgic or ordinary recall of a collective event, Irish participants were given a set amount of tokens and then asked to observe a token-sharing transaction between an Englishman and an Irishman. When they saw the Englishman make an unfair offer, the participants had the chance to punish him, but at their own cost in tokens. Choosing to punish the unfair English player was taken as a sign of in-group loyalty.

Nostalgia encouraged more self-sacrifice for the group, but only in some participants. Specifically, those who strongly identified as Irish from the outset of the study sacrificed nearly half their stash for a stranger. Those who felt less affiliated sacrificed a fifth, which was no more vengeful than those without a nostalgia induction. Wildschut notes that direct effects of emotion onto specific behaviours are generally much weaker than intentions, because participants might find other ways to act outside of the confines of the study.

Rather than being without function, it appears that nostalgia is an organising emotion, strengthening group membership and developing collective identities. It can be used to ugly ends: politicians appealing to mythical pasts to paint outsiders as threats. But it may also help migrants to maintain solidarity and meaning in new environments that can be hostile or non-inclusive. And for any of us, giving in to a nostalgic impulse may be enough to inspire picking up a phone and making contact with people we've been apart from for too long.

Further reading

Wildschut, T., Bruder, M., Robertson, S., van Tilburg, W., & Sedikides, C. (2014). Collective nostalgia: A group-level emotion that confers unique benefits on the group. Journal of Personality and Social Psychology, 107 (5), 844-863 DOI: 10.1037/a0037760