In 1989, when the Mirage Hotel in Las Vegas was built, a crazy urban legend arose to explain the hotel’s financial success.

“People were saying that Steve Wynn had discovered the odor that makes people gamble,” remembers Mark Peltier, whose company, Aromasys, created the aroma dispersed in the Mirage’s casino.

“Katie Couric burst into our offices with cameras and bright lights and started interrogating me,” Peltier says. “She asked how we manipulate hotel and retail customers with our aromas. I told her that manipulation is not what we do. Our system just adds to the décor of a site, similar to the color of walls and background music. And we use aromas that are no different than those found in nature. No one would accuse a forest or flower garden of manipulating us into doing things we didn’t want to do. We just make the commercial properties more pleasant places.”

Peltier’s company also developed and implemented the fragrance at The Venetian and Palazzo. However, I first learned about some people’s strange fear of aroma-décor while reading See What I’m Saying: The Extraordinary Powers of Our Five Senses by Lawrence Rosenblum, professor of psychology at the University of California, Riverside.

It’s an immensely interesting book, summarizing the latest scientific research into our five senses.

Applying aroma to an environment is, of course, nothing new.

“Scent has been used in public spaces for thousands of years,” Rosenblum says. “The Moors developed a method to preserve frankincense in brick mortar so that its odor would infuse mosques years after building was completed. And it’s a well-known realtor trick to bake cookies during an open house to give the home a warm, inviting appeal…. Bloomingdale’s currently uses a different scent in each of its major departments (baby powder scent in baby apparel; coconut scent in swimwear).”

Scents are now being dispersed in commercial spaces—malls, hotels, spas, casinos, retail stores—throughout the world. 

“The goals of using environmental aroma are not much different from those of visible décor design,” Rosenblum explains. “Both methods attempt to make a commercial environment more inviting and relaxing so that customers want to remain in the space.”

Can these smells influence you to make decisions—like gamble your money—which you otherwise wouldn’t?

Nope, says the scientific research.

Rachel Herz, professor at Brown University Medical School, and author of The Scent of Desire, found that “a subject’s opinion of a novel scent can be changed after just 15 minutes, depending on whether that scent is present when a subject is winning or losing money. It seems clear, then, that your opinion of odor can be determined by your associations with that odor.”

Loss at a casino, or any other negative experience for that matter, may well lead you to hate the fragrance around you. By contrast, a positive experience might enhance your enjoyment of the smell. Your general experience, in other words, influences your reaction to the particular aroma, and not vice versa.

Rosenblum adds that “research also shows that these same effects can be induced by pleasant looking décor or nice sounding background music. And while a store’s scent can, in theory, render a patron’s thoughts and memories as more emotional, it is also more likely to induce a strong negative reaction in patrons if they find it unpleasant.”

“So while environmental scent may be a novel addition to a hotel or store’s décor,” Rosenblum concludes, “there is no evidence that it has special coercive powers. A smell can’t brainwash you into gambling, or staying at a hotel you don’t like, or buying something you don’t need.”