Software developer Loren Brichter created the pull-to-refresh interaction for his company Tweetie, a Twitter client launched in 2009. Reminiscent of drawing back a slingshot, the feature brought a playful, kinetic quality to content discovery. It also took advantage of the human brain’s reward circuitry, which is wired to produce more dopamine when we anticipate a reward than when we actually get it—especially if the reward is uncertain.

On what’s now called X, pull-to-refresh works in tandem with infinite scroll, loading new updates while the latter delivers an algorithmically ordered stream of older content. But the interaction has become standard behavior across the larger mobile app ecosystem, allowing us to refresh on muscle memory alone. We know that pulling down generates new likes, new comments, and new connections. Beyond social media, the gesture is also how we get the latest on everything from breaking news to weather reports, and stock prices to concert ticket drops, inextricable from our need for real-time information.