“Another time, we put off our son’s dental work to be able to afford our annual trip to Disneyland,” she says.

She’s far from being alone. One analysis showed that 18% of Disney park goers go into debt to pay for their Disney vacation. For fans like Jeff Reitz of Huntington Beach, who famously visited Disneyland 2,995 days in a row, such habits can become an obsession.

And though other theme park destinations can claim they have loyal fans of their own, none of them can deny Disney’s appeal to the masses. Disney’s six U.S.-based theme parks are visited more annually than the next 13 most popular U.S.-based theme parks combined.

Why are people so drawn to the happiest place on Earth? The answer may have to do with how our brains are wired. While many factors no doubt contribute to Disney’s enduring popularity, some scientists believe that Disney-related vacations prompt more compulsive travel behavior than others, due to the powerful strategies the company employs. The next time you find yourself with a strange yearning to inhale the damp, musty air of Pirates of the Caribbean or walk along charming Main Street U.S.A., consider these possible reasons for it.

Travel craving is real

Though research around “travel craving” is new and relatively sparse, behavioral psychologists and cognitive scientists believe a yearning for travel can fit the clinical understanding of craving as “a strong desire to modify ongoing cognitive experiences” in ways that don’t only relate to addictions.

Neuropsychologist Paul Nussbaum, an adjunct professor at the University of Pittsburgh School of Medicine, explains that such cravings can be especially focused on getting specific outcomes from one’s vacation. “Our brain’s circuitry is wired to both desire things and to have our desires resolved temporarily with action,” he says. In other words, for people who describe their love of Disney travel this way, craving a trip to Disneyland may not only be a desire, but a yearning that continues to grow until satisfied.

(Patrick Hruby / Los Angeles Times)

Something smells funny

Such yearnings are fed by any number of factors, of course, but smells are high on the list because of how they trigger memories and positive emotions. “The brain region critical to smell is located near the hippocampus, which is an important brain structure that helps us remember,” Nussbaum explains. “That is why the sensation of smell can trigger memories.” Indeed, multiple studies show how one’s sense of smell has a stronger link to memory and emotion than any of the other senses.

Disney seems to understand this as it has filled its parks with machines called Smellitzers — apparatuses carefully disguised or hidden away throughout attractions, shops and walkways, each pumping out soothing and familiar scents to passersby. In a 2017 interview, a 30-year Disney parks veteran said these machines release these familiar scents “on purpose” because the company is mindful that visitors “are using all their senses” when they’re there. But beyond simply releasing the smells, Disney also uses carefully timed systems and fans to ensure those scents reach the nostrils of guests. One Disney attraction patent notes that the ride’s Smellitzers’ “nozzles may be provided to direct scent materials into proximity to the fans so that appropriate scents may be directed to the passenger.”

While many parkgoers undoubtedly love the distribution of such smells on attractions and while shopping, one fan went viral on TikTok for saying Disney’s use of Smellitzers “brainwashes” people who attend the parks into making purchases they may not otherwise make.

Brainwashing or not, the effect “is ingenious,” says Melanie English, a licensed clinical psychologist in Seattle. She explains that not only do such smells release happy hormones in visitors, but breathing them in can actually reduce stress. When taking the slow, deep breaths required to take in each aroma, she explains, parkgoers “complete some inadvertent meditation, which slows their heart rate down and reduces their cortisone levels.”

Not only do Disney Smellitzers enhance the visitor experience, but because of how strongly smells are linked with memory, the scents can pull visitors back to the parks whenever they get a whiff of similar aromas that remind them of the woodsy pines around Grizzly Peak in Disney’s California Adventure park or the freshly baked goods along Disney’s Main Street U.S.A. One scented candle company understands how powerful these smells can be and sells candles that capture the “damp ocean air” associated with the Pirates of the Carribean attraction, the “etherealizing scent” of riding Haunted Mansion or the “earthiness” of Soarin’ Around the World.

“Smell is a chemical sense, and it is evolutionarily ancient, so it connects more directly with the emotional parts of the brain than the other senses do,” explains David Ludden, a professor of psychology at Georgia Gwinnett College in Lawrenceville, Ga. “While some odors rise to the level of consciousness, many smells influence our behavior at an unconscious level,” he says, adding that Disneyland’s ability to evoke such unconscious emotions and connect with visitors so deeply is “a big part of Disney’s success.”

(Patrick Hruby / Los Angeles)

Feeding peer influence

Beyond its unique methods for distributing smells, Disney also benefits from and contributes to established social behaviors regarding peer influence. Though people frequently take and share pictures of many types of travel, few vacations feel as obligatory to document as a trip to Disneyland. Andrew Selepak, a social media professor at the University of Florida, says people are highly influenced by the images their friends and family members share on social media. “Family vacations to Disney are not just photos of the family in mouse ears or after a fun ride, but the entire park,” he says. “We take pictures of our food, the things we buy, the lines we wait in, and even the most minor of moments to post and share in social media.” Ludden echoes that because of how often people chronicle their Disney vacations, those following them from home feel especially driven to experience and share the same vacations so they can “belong to the elite group of those who have ‘been there, done that.’”

Selepak believes Disney recognizes its influence and points to the effort it puts into setting up meet-and-greets with beloved characters, creating eye-popping backdrops and decor, and coming up with photo-worthy treats and souvenirs. This year, Disneyland also made Disney PhotoPass digital attraction photos free for ticketed guests, encouraging more people to share images with their friends and followers.

And while lines at amusement parks aren’t unique to Disneyland, the experts say Disney’s efforts to entice social media sharing pays off in ways efforts at other destinations simply don’t. “How many other theme parks have you been to where the line to get a photo with a costumed character like Mickey Mouse is as long as some of the rides there?” asks Selepak.

(Patrick Hruby / Los Angeles)

Nostalgia we’re wired to crave

Perhaps Disney’s most powerful strategy is how it triggers feelings of nostalgia through its many throwback details: old-time attraction posters at park entrances, a train whistle sounding from a steam-powered locomotive as it loops around the park, classic movie characters mingling in real life with guests, a horse-drawn street car transporting visitors along Disneyland’s most visible walkway and the architecture of Main Street U.S.A. built to resemble Walt Disney’s idyllic turn-of-the-20th century hometown. Even more recent attractions take guests back to the classics — for instance, Mickey & Minnie’s Runaway Railway is designed to transport riders into vintage-style Mickey Mouse cartoons.

“Visiting Disney parks allows people to indulge their nostalgia by immersing themselves in this reliable world filled with familiar colors, characters, smells and music,” says Erica Hepper, a lecturer of psychology at the University of Surrey in England and author of multiple nostalgia-related studies.

The rewards associated with such wistful remembrances or feelings of nostalgia are many and include improved mood, feelings of optimism, stronger social bonds and reduced anxiety. Hepper says experiencing nostalgia this way not only rewards park visitors while they’re in the parks, but also motivates them to want to return when they see nostalgia-triggering Disney films at home or encounter Disney-themed merchandise and ads, which are everywhere.

What’s more, because Disneyland opened nearly 70 years ago, many adults today have some of their fondest childhood memories rooted in a visit there. “Childhood is a time of security, innocence, fantasy, and carefree and exuberant joy,” says Krystine Batcho, a psychology professor at Le Moyne College in Syracuse, N.Y. Because of this, she says Disneyland is “strongly evocative of nostalgia” and makes people naturally long to return to experience their treasured childhood emotions anew.

Ludden agrees, saying that Disney theme parks provide a “nostalgic refuge” for adults seeking to escape their stressful lives.

Indeed, it’s this use of nostalgia marketing combined with these other subtle strategies that the experts say contributes to the overall experience and makes guests of all ages want to return to the happiest place on earth again and again. “Disney is absolutely special in creating smells, foods, experiences and merchandise that pair very well together,” says English. “Collectively, this brings people back to their parks — and with joy.”