Q. Have you noticed personal changes in which scents appeal to you over the years?

A. Yes in terms of fine fragrances. My first favorite perfume which I wore for about 4 years was Anais Anais, my next was Alfred Sung. I chose these two fragrances because friends of mine were wearing them and I liked how they smelled. I wore Alfred Sung for a long time and then in my early 30’s I switched to Neiges by Lise Watier. One of my reason for choosing this scent was because it was made by a Canadian designer so no one in the US, where I was living, would smell like me. I wanted to make my fragrance mark.

I used to be a one perfume loyalist no matter what the situation. More recently, I have started to alternate between three fragrances: Neiges, Juicy Couture, and She by Giorgio Armani. I tend to wear these different perfumes for different occasions or for how I want to feel at certain times.  I also like to create specific personal and scent memories with a new perfume if I'm going on a special trip.  I use scent to take a picture of my emotional experience.

Q. Research shows that women choose prospective mates, in large part, on the basis of the male’s scent. Were you conscious of this fact when you met your husband? Have you heard anecdotal reports from friends about this important role scent plays in our lives?

A. Actually, my husband’s scent did figure prominently in my attraction to him and still does. Many women have told me that they knew they would marry as soon as they first smelled him. 

Where do humans rank among other animals in the importance of scent in their understanding of their surroundings? Which animals are more sensitive to smell and which less?

A. Humans have traditionally been characterized as quite low on the animal totem pole for scent sensitivity. However, researchers have proven that we are actually quite good at detecting scent, though we are still less keen than other mammals (with dogs being the very best). Most mammals use scent as the principal sense through which they understand and explore their world. The presumption that smell is of little importance to us and our world, however, is much more cultural than physical.  There are at least several hunting and gathering peoples around the world who use scent as the primary sensory medium through which the categories of time, space and individuals are conceptualized. As we Westerners come to understand our sense of smell more and its essential involvement in our lives we will be better able use scent to understand our world.

Q. What are you working on next?

A. I am continuing to do research on many of the topics that I have covered in my books to date.  Thinking, researching and writing about the interplay of our psychology and biology and what makes us human is my overarching goal.

Q. Do you personally have any other “Proustian” scent that triggers a particular memory?

A. Yes, two of them immediately come to mind. One is the smell of the perfume my mother wore during the time we lived in Paris, when I was 4 or 5, called Crepe de Chine. Unfortunately this perfume is no longer available, though I have tried to hunt it down and even contacted the perfume archives at Versailles. I could have gotten a bottle through the Versailles collection but it would have been an ordeal. Fortunately my mother had kept an old bottle that I now have at home and I go to it from time to time to conjure a special scent memory.

The other Proustian scent I remember vividly is the cologne worn by my first boyfriend who came from Chile — his fragrance was Nino Cerruti. Although the last time I smelled it on him was almost 40 yrs ago I use this scent now as a memory test and every few years I sniff the empty bottle that I’ve kept in my childhood bedroom to see if I can conjure the memory of those early days. It still works. 

Whenever I go to these fragrance bottles and uncork the genie inside, I always feel infused with a wonderful, powerful happiness. My emotions are at least partly due to the fact that I am still amazed at how smell, like none of my other senses, can transport me to a different time and place.

An Interview with Rachel Herz conducted by WILLIAM MORROW, an Imprint of Harper Collins Publishers, shortly after the release of The Scent of Desire  in 2007.

Q. How did you become interested in the psychology of scent?

A. I have always been a “sensual” person and literally take time to smell the roses. I have also always been scientifically interested in the interaction between psychology and biology and studying scent is the perfect way to do this. I believe scent is also the Rosetta stone for understanding emotion, another topic which fascinates me.

Q. As a child, you moved with your parents (an English professor and a mathematician) to various universities in the U.S., Europe, and Canada. Do you remember differences in how each of these three Western cultures value scent?

A. I was too young to appreciate most of the scent differences between the countries that I lived in, because I was only 7 when we made our final move to Canada, but I do remember Paris to be particularly scent-ful and pleasantly so. One of the scents that can transport me back in time and space, but which unfortunately requires fate for me to stumble upon, is a concatenation of baking butter, coffee and a tinge of cigarette smoke and car exhaust, in a particular combination it elicits a strange and wistful nostalgic feeling and always brings me back to Paris.

An Intimate Interview

Q. Of the many experimental studies you have conducted over the years, which have you found most illuminating, surprising?

A. In my work on sleep and circadian rhythms, I've been fascinated to discover that we don't smell while we are in deep or dreaming sleep,  and also that our sense of smell is worst during the circadian phase when we would be asleep.  This finding is extremely important because of the implications regarding house fires and the necessity of having auditory smoke alarms.  I've also been amazed at our finding that people believe a scented product works better (e.g., makes your skin softer and smoother) if they personally connect with the scent of the product.  In other words it's not the product per se, but how it smells to an individual that drives the perception of its efficacy.

Q. You regularly work with perfume and flavor producers. What kind of help do you provide them?

A. I help fragrance and flavor companies understand where our scent preferences come from, how they can be changed and how emotion and memory can be manipulated by scent to increase product appeal and loyalty. I also help them understand how language can influence scent perception and how to most effectively utilize this force.

Q. Have your years of study made you more attuned to scent in your everyday life? Have you (or can anyone) train themselves to become a “supertaster?”

A. Yes, I have become more attuned to scents over the years. When I began my dissertation research and started working with a large collection of scents, preparing them, making dilutions, testing them and learning their names I discovered I was exponentially increasing my scent vocabulary and doing so made me appreciate and able to recognize many smells that I hadn’t even noticed before. Everyone can increase their olfactory ability by simply paying attention to scents.

I am a “supertaster,” but that is due to genetics. Supertasting does not appear to be anything that you can train someone to be. However, some genetic, hard-wired responses to odors do respond to training or exposure. People with a specific anosmia to androstenone, a steroidal musk compound, can become androstenone smellers if they are repeatedly exposed to it. This was serendipitously discovered by Chuck Wysocki at the Monell Center when he had his anosmic subjects come back to the lab frequently for follow up tests, and over time observed that they became “cured” of their androstenone blindness. 

Q. You undertook a study commissioned by the Sense of Smell Institute for Oprah Magazine in which you interviewed women visiting the Sephora store in Times Square. Were the individuals you interviewed eager to talk to you about their scent preferences? Did you find that they intuitively knew how important scent is in their lives?

A. Almost all the women I approached were happy to participate in the study. They were very eager to share their scent predilections with me, even personal and intimate details. Of the 113 women in the study, all but two knew that scent was very important to their lives — not just intuitively, they were able to be very explicit about it. Though many of them confessed that they had never before thought about fragrance and psychology in the way I was asking them to. Their stories were as much a revelation to many of them as they were to me.