Thinking about the past is a natural human tendency, but psychology has yet to understand its roots.

A new study tests 5 principles that can explain why people engage in nostalgia and how it can be beneficial.

By allowing yourself to explore your past, you can prepare yourself to manage life’s current challenges.

Everyday life can often become crowded with thoughts and feelings about making it through the day. You often have little time to contemplate your next actions, much less dwell upon those that are in the past. Yet, occasionally, you can find yourself drifting off into thoughts about the old days without realizing why.

Bruce decided to treat himself by going out to a concert. Although the music was very compelling and he soon became immersed in it, all of a sudden, a memory flickered through his brain without any clear explanation. He remembered an old friend of his from high school, along with some of the fun they used to have together. As he forced himself to snap out of the recollection, he made a mental note to check on that friend and see how he is doing. But what triggered the memory in the first place?

The Psychological Roots of Nostalgia

As noted by University of Southern California’s Evan Weingarten and colleagues (2026), who cite previous research, “nostalgia is ‘fundamental to human nature itself.’” We just can’t stop ourselves from letting our minds go backward. The USC researchers believe that the causes of nostalgia relate both to (a) the need to cope with threat and (b) the desire to galvanize or motivate people to seek positive affirmation, connections to others, and connections to our very identity.

These two approaches, the so-called “regulatory” and “motivational potency,” are all very well and good, argue Weingarten, but they’re not very specific. Drawing from 135 published datasets and 35 unpublished ones, Weingarten et al.........

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