SACHA PFEIFFER, HOST:
There's a new fragrance out with hints of citrus, beech trees and red maples. Its name is One World. But you won't find it being spritzed around the perfume department at Macy's. This fragrance was designed to be pumped into the observatory space at One World Trade Center in Lower Manhattan.
According to a recent story in The New York Times, not everyone likes the idea of a scented public space. One tourist described the smell as sickly. That's not what the observatory's managing director intended. He says he wanted it to elicit a, quote, "positive thought" about One World.
Dr. Alan Hirsch is neurological director of the Smell and Taste Treatment and Research Foundation in Chicago, and he joins us to talk about the psychology of pumped-in fragrances. Dr. Hirsch, welcome to the program.
ALAN HIRSCH: Well, thank you for having me.
PFEIFFER: How can smells affect the mood of people in public places?
HIRSCH: Well, the quickest way to change somebody's mood or behavior is with smell because a part of the brain that we think smell - the olfactory lobe is actually part of the limbic system or the emotional brain. So when you smell a smell, you immediately decide, I like it, or, I don't like it, and then you figure out what it is, which is totally different than all the other sensory spheres. So for instance, you see a picture of a cow or a tree or a horse, you identify it, and then you'll decide if you like it or not. It's totally different with smell. With smell, it's a purely emotional sense.
PFEIFFER: And a bad aroma can put us in a bad mood.
HIRSCH: Exactly. Not only will pleasant odors induce people to be in a happier state, but an unpleasant or irritating aroma can make somebody be more aggressive and angry. If it happens to be an aroma that your ex-wife wore, or ex-boyfriend, and you have a negative feeling towards them, you develop the same emotions when you're exposed to those aromas.
PFEIFFER: Right, it's very subjective. I'm thinking about different stores I've walked into that had intentional smells, like the smell of cinnamon at Yankee Candle or Subway sandwich chain piping out the smell of bread. How common is it for buildings or building managers to inject fragrances or odors to enhance a visit?
HIRSCH: Well, far less than 1% of stores - probably closer to 0.1%, partially because we're such a heterogeneous society. So for instance, not only do different individuals have different perceptions of whether they like or dislike the aroma, but also, they have different abilities to smell. So women have a far better ability to smell than men do. As you get older, your sense of smell drops down. So about half of those over the age of 65 and three-quarters of those over the age of 80 have a reduced ability to smell. On top of that, in the morning time, one's sense of smell is far greater than later in the day. And if you've just eaten, your sense of smell is even - it reduced even more.
So what happens is all of us are walking around with different abilities to smell and with a different perception of what's pleasant and what's unpleasant.
PFEIFFER: Does that mean that many stores are reluctant to try to impose a certain scent on us?
HIRSCH: Well, that's right. Part of it is that what happens is as we've experimented with different aromas, we find that the odors that people like - say they like are not necessarily what they actually do like. So when you come into a store, and let's say you're selling leather goods, when we experimented and tried to put a leather smell there, people disliked it. We finally put a combination of leather, baby powder and citrus. They found it in a more positive way and, hence, stayed in the store longer.
Similarly, certain odors are incongruent with what one is looking at. So for instance, when the smell of fish was present in a store that sold clothing, people left the area because they didn't like the smell of fish. It was not contextually appropriate for what was being sold. So you have to make sure the odor is appropriate.
On top of that, people want to see where the odor is coming from. They don't like the idea that they're being manipulated by an aroma in the environment. So if there's flowers there, having a floral aroma would be appropriate. Having a smell of bread baking, on the other hand, would not be.
PFEIFFER: There is research that suggests that music in stores can affect people's buying habits or, for example, how quickly they eat in a restaurant. Do smells have similar effects?
HIRSCH: Absolutely. For instance, we found a mixed floral smell increased speed of learning by 84% compared to a no-odor condition. Also can impact upon, for instance, perception of room size. We found that a smell of cucumber and green apple made people perceive a room as larger, whereas the smell of barbecued, roasted meat - they'll perceive it as smaller.
PFEIFFER: Dr. Hirsch, I'm wondering if you personally have any environments where the smell puts you in a good mood.
HIRSCH: Oh, well, I always like to smell chocolate chip cookies. That doesn't necessarily mean I want chocolate chip cookie smell around when I'm buying a suit. But still, a pleasant aroma that makes us happy, that makes us nostalgic for our childhood tends to induce a positive state, and, thus, we view everything around us in a more positive way.
PFEIFFER: Dr. Alan Hirsch is neurological director of the Smell and Taste Treatment and Research Foundation in Chicago. Dr. Hirsch, thanks for talking with us.
HIRSCH: Thank you.
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