Taylor Swift never bores her fans — never ever, ever, ever

Here’s a defining feature of our species: We get bored. If you have been in the same city for five years, you might stop noticing what’s charming about it: the side streets, the old buildings, the open spaces. The first weeks on a new job might be thrilling — the people, the workspace, even the work. After a year, everything might seem to be dull as dishwater. You might have a favorite song, but if you hear it a lot, it will become tedious. The same might well be true of your favorite singer.

The reason? The technical answer is “habituation.” A defining characteristic of the human brain is that if we are repeatedly exposed to the same thing, or “stimulus,” we will become decreasingly sensitive to it over time. That’s why you might not even notice a background noise in the room where you are right now. It’s also why people who are startled by an unpleasant smell when they first enter a room (perhaps someone is smoking?) might not even detect that smell a mere 30 minutes later.

Our brains are acutely sensitive to surprises, which means that we are on the alert, and tend to jump, when things change.

When things stay the same, well — they start to turn gray.

Which suggests a puzzle. Taylor Swift has been around a long time. (Sorry, Ms. Swift.) Her first hit, “Tim McGraw,” was released in 2006 — during the presidency of George W. Bush and before the iPhone.

Here we are, 18 years later, and Swift’s fans are hardly bored by her. If anything, their devotion seems more intense than ever. Why is that?

A large part of the answer is simple: Swift is a master of the surprise signal. She spurs curiosity. She’s the reigning queen of dishabituation. Taylor never repeats herself. She’s 34 and already has an Eras Tour, signaling her capacity for reinvention.

For those who are late to the party: Originally a country singer with a twang (listen to “Our Song”), she quickly became a pop singer (try “Red” and “22”), turned much edgier (“Welcome to New York,” “Out of the

Woods,” “Bad Blood”), got really, really mad while retaining her sense of humor (“Look What You Made Me Do,” “…Ready for It?”), and then went indie folk (“Betty,” “Cardigan”). The whole idea of an Eras Tour signals Swift’s spectacular ability and desire to abandon a well-trodden path and try something altogether different.

In that way, Swift is a lot like The Beatles and Bob Dylan, also masters of dishabituation. In their relatively short time together (about 10 years), the Beatles had their own eras. The same is true for the mercurial Dylan: folk singer, protest singer, rock star, country singer, gospel singer, old-style crooner, and much more. (No eras tour for that guy; unlike Swift, he doesn’t look back.)

Part of Swift’s unique genius is that she’s able to combine novelty with familiarity. Her songs create a kind of chain novel, with continuity from one chapter to another. She nods to the past; “the old Taylor is dead,” she sings in “Look What You Made Me Do,” even as she winks to the audience that obsessively follows the narrative of her life. She’s unfailingly inclusive of that audience: “We’re happy, free, confused and lonely at the same time/It’s miserable and magical, oh, yeah,” she sings in “22.”

She’s full of surprises. On “Saturday

Night Live” in 2009, her “Monologue Song” said this: “I like writing songs about douchebags who cheat on me/But I’m not going to say that/In my monologue.” She parodies her public image: “Got a long list of ex-lovers/They’ll tell you I’m insane,” she says in “Blank Space.”

She’s sweet (”I love each freckle on your face,” she sings in “Jump Then Fall”), and she’s joyful, and she’s kind, but she also has an edge (from “Mean”: “Washed up and ranting about the same old bitter things/ Drunk and grumblin’ on about how I can’t sing”). She’s inventive (“You’re the only thing I know/Like the back of my hand,” she sings in “Breathe”).

There’s a big lesson here. Because of habituation, people tire of the most amazing things, including writers, musicians, actors, and artists. Of course it is true that familiarity, and a sense of personal connection, can cement someone’s appeal. But without a surprise signal, even the brightest colors lose their luster.

More than any other performer today, Swift gets that. It’s her secret sauce.

In a way, Swift is a lot like The Beatles and Bob Dylan, also masters of dishabituation.