It’s an attitude, a term of approval, and today, as much as any of these things, it’s a game of superficially rebellious status-chasing, centered on consumerism.

In the early 2000s, a major shift happened in the way people dress. Flared and baggy jeans began to give way to a skinny, low-slung version, and by the end of the decade, it seemed everyone—including menwere squeezing into jeans so tight that doctors began issuing health warnings. Now skinny is the status quo, and fashion’s early adopters aresearching for a new look.

These sorts of back-and-forth trends may seem frustratingly arbitrary, but there’s a tremendous force involved in the shrinking and growing of jeans. It’s called “cool.” It’s an incredibly powerful marketing tool—one that has driven the astronomical profits of companies from Nike to Apple to Kanye West’s Yeezy—and nowhere is its influence as obvious as in our clothes. Cool doesn’t just explain why people will pay $1,000 for the right sweatshirt. It’s also arguably a factor in why the right logo makes us view some people as more suitable for a job, or worthy of receiving money for charity.

What it is, exactly, is a little hard to define, but there are hints in its history, in trends, even in neuroscience. Cool is a target that’s constantly shifting. It’s an attitude, a term of approval, and today, as much as any of these things, it’s a game of superficially rebellious status-chasing, centered on consumerism.

You can actually see cool in the brain

Elusive as cool is, the way we experience it stems from some very specific places.

Steven Quartz and Anette Asp, neuroscience researchers at the California Institute of Technology, have run fMRI studies on the brains of people looking at items that a separate group identified as “cool” or “uncool.” Just viewing these objects activated a part of the subjects’ brains called the medial prefrontal cortex (MPFC). It’s involved in social emotions, such as pride and embarrassment, that center on how we perceive ourselves and believe others perceive us, and it has strong ties to the brain’s reward and disgust circuits.

The finding establishes an interesting connection between what we perceive as cool and our feelings about our place in society, as Quartz and Asp explain in their book, Cool: How the Brain’s Hidden Quest for Cool Drives Our Economy and Shapes Our World. The cooler the subject found the product to be—Quartz and Asp surveyed what they considered cool as well—the more active the MPFC became. They believe it suggests that the subjects’ brains were responding to how they thought the product might boost their esteem in the eyes of others.

“Cool turns out to be a strange kind of economic value that our brains see in products that enhance our social image,” they write. It’s a powerful quality: “This abstract good—social approval, reputation, esteem, or status—plays a central role in our motivation and behavior, and it is the currency that drives much of our economy and our consumption.”

Cool isn’t alone in raising status or getting people to buy. An item’s price tag can do that, too. But it’s distinct in one specific regard: It’s got a connotation of bucking the mainstream, and that’s where jeans come into play.

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