Scrolling through Instagram can quickly convince you that everyone’s life is more interesting than yours. During a particularly adventurous week on Instagram Stories recently, I saw water skiing in Maui, hiking in Yosemite and swimming with wild pigs in Bermuda. Wild pigs!

Impulsively, I started Googling flights to new places. Then I ordered pho from the same Vietnamese place I eat at every week and … felt bad about not trying somewhere new.

This fear of missing out is rooted in a common psychological tic: Evolutionarily, we’re disposed to find novel experiences more exciting and attention-grabbing than repeat experiences, according to research published in the Journal of Experimental Biology. It’s basically fight or flight psychology — our brains can’t process all the stimuli around us, so we evolved to pay attention to new, flashy and potentially dangerous things more intently than familiar things, which we’ve seen enough to know they’re not dangerous. What’s more, words like “repetition” and “repetitiveness” — unlike “novelty” — tend to be associated with more negative emotions, said Michael Norton, a professor at Harvard Business School.

“Classic research shows that when we think about upcoming experiences, we think about variety,” said Mr. Norton, who specializes in consumer behavior. “If I ask you right now to select a yogurt for each day next week, you’ll pick your favorite flavor — say, blueberry — a few times, but you’ll mix in some strawberry and peach. Because who wants to eat that much blueberry yogurt? Over the longer term, though, as the original experience fades in time and memory, repetition can become more pleasurable.”