Starbucks is promoting pumpkin this season. (Lexie Barker / Neon Tommy)

As its advertising slogan proclaims, Starbucks is “celebrating a decade of pumpkin devotion” in stores and online. Menus behind the register picture a giant pumpkin spice latte, nicknamed the “PSL,” beside a "Pumpkin Cheesecake Croissant" and "Pumpkin Sugar Cookies." Coffee sleeves, with orange-silhouetted pumpkins and their namesake lattes, pay homage to the milestone anniversary. You can buy a “PSL” 10-year tumbler to prove you were part of the celebration. A website, dedicated entirely to the fall favorite, launched before the drink’s Sept. 2 release. Photos of the “PSL” and its devoted fans decorate the screen while tweets shuffle across at the bottom. “I’ve been waiting all year to be reunited with my love,” reads one tweet.

It’s true. Coffee drinkers are passionate about pumpkin. Starbucks reports there have been more than 29,000 tweets with hashtag #pumpkinspicelatte in the last year. Since the drink’s debut, fans have downed over 200 million cups of “PSL.” It’s the most popular seasonal beverage in company history. And Starbucks is pleased. At an average cost of $4 a latte, the coffee industry’s Goliath sees revenues of $80 million each fall from the beverage.

For all the hoopla, the drink actually contains no pumpkin. It’s like shrimp scampi sans shrimp or a BLT without bacon.

The pumpkin itself is nothing more than a humble squash with little flavor. It requires a proper dose of sugar and more than a touch of spice before it becomes palatable. In sweet and savory preparations, it is often accompanied by cinnamon, nutmeg, ginger, and cloves. The spices, now sold together by food retailers as “pumpkin pie spice,” give pumpkin pie its flavor and distinctive aroma.

Given the consistent pairing of pumpkin and spice mix, our brains create an inextricable link between the two. While other companies deliver the product they promote, Starbucks is actually delivering the essence of pumpkin pie, but promoting pumpkin. Their seasonal superstar is flavored with “pumpkin pie spice,” not with pumpkin. Most of us do not differentiate between them, so we fall for the pumpkin facade.

The “PSL” is delightful, don’t get me wrong. I willingly offer up $4 for a tall "Pumpkin Spice Latte," hold the whipped cream, on the regular these days. But, the success of the drink is driven by an emotional response that pumpkin triggers.

It makes sense when you consider how our brains work. Imagine them as power grids and a single idea, like pumpkin, as a power plant. Just thinking about pumpkin sparks many other ideas related to pumpkin, like orange, autumn, and pie. Nobel Laureate psychologist Daniel Kahneman describes our brains as associative machines and calls this process associative activation. “Each element is connected,” he writes in his book Thinking, Fast and Slow, “and each supports and strengthens others. The word evokes memories, which evoke emotions.”

A pumpkin sends many of us right down memory lane. It reminds us of carving jack o’lanterns, visiting pumpkin patches, and baking pies. Were you surrounded by your friends and family? Was the weather crisp and clear, invigorating after a long hot summer? Those memories prompt emotions that trigger an emotional response, most likely a positive one.

These echoed emotions can have a significant effect on the choices we make. When you buy yet another pair of brown heeled boots or “treat” yourself to that brownie sundae, you are making choices based on the emotion of desire, not logic. Logic compels you to forego the boots and the brownie because with a closet full of brown boots, another pair isn’t necessary and with so much sugar, the sundae isn’t healthy.

To be honest, I’m all for giving into desire at the right times, but differentiating between emotion and logic helps us understand how advertising works.

Get a whiff or take a sip of a "PSL" and your brain instantaneously and unconsciously links to those good vibes. The positive emotional response encourages customers to buy pumpkin spice lattes and to continue buying them.

It doesn’t hurt Starbucks’ marketing strategy that you are seeing pumpkins everywhere else. They’re falling out of bins at grocery stores where pumpkin soup, pumpkin ravioli, and pumpkin ice cream are taking up shelf space. Pumpkin Halloween costumes, never a hot seller, are always laying around at costume stores and neighbors are beginning to dot their door steps with pumpkins.

After so many sightings, the connections between the latte, pumpkin, personal experience, and positive emotion come quickly. This fluid chain reaction is an example of “cognitive ease.” A consequence of cognitive ease is feeling good - another reason to fill up on those “PSL” while we can. Whether or not it contains actual pumpkin is besides the point.

Reach Staff Contributer Lexie Barker here.