Scent is a powerful, even hypnotic, sense. It can be an aphrodisiac — or can make you nauseous. It can conjure sweet memories of a summer romance — or offer a pungent reminder of a relationship gone sour. It can transport you to a place where you were happiest — or most miserable.

Fragrances often conjure tactile sensations, as well as moods and emotions. The olfactory senses have a memory of their own.

Many visitors to our Islands say one of their fondest memories is the scent of flowers, especially pikake, ginger and plumeria, or the fresh scent of ehukai (sea spray).

Aromatherapist Maryann Rose Broyles, creator/owner of Hana Nai'a Aromatherapy on the Big Island, relies on plants for her livelihood. She finds her sense of smell is critical to her success in creating her therapeutic aromatherapy oils.

"The limbic system in our brain is very powerful, especially on one's psyche. It awakens the memory of ancient past, so healing happens on a soul level. It is the seat of emotions as well. My mentor John Steele teaches me to listen to the plants. It is a delicate balance," she explained.

Since fragrances can play such an important role in our lives, we decided to learn more about this delicate, yet powerful, sense.

CHOOSING A FRAGRANCE

We asked Honolulu-based perfumer Kate Growney, creator of Saffron James fragrances (sold at Nordstrom), how to choose a scent for someone else.

"It's not about what you like," Growney said. "It's about taking the time to think about what they like.

"When I choose a perfume for someone I ask myself a lot of questions about who they are: What kind of food they like, what their favorite color is, who is their favorite designer, what kind of music do they listen to, where they grew up, where they like to travel. The answers will tell you a lot about what type of scent they would like.

"For instance, someone who grew up in Hawai'i most likely will like a floral (scent), as opposed to someone who grew up in the Midwest, who might prefer woods and grasses. Someone who loves to shop and dresses in couture will like something new and unique; someone who dresses more conservatively will appreciate a more traditional scent."

If you're standing in the middle of a department store wondering what scent to buy as a gift, Growney suggested, it helps to know what scent the recipient wears now.

"Most perfumes can be broken down into scent categories: floral, spicy, woody, earthy, edible, fruity, citrus, green, herbal, marine. If you can identify the category of the perfume they already wear and choose something in that category, or in one similar to it, it's a pretty safe bet."

"Fragrance is a wonderful gift," said Yosh Han, the San Francisco perfumer who creates the Yosh line of fragrances sold at Barneys New York and www.eaudeyosh.com. "It implies thoughtfulness and luxury. When you decide on a fragrance style, consider the personality and social activities. Someone who enjoys outdoor adventures will enjoy fresh, green aromas. Someone who is a big foodie or wine connoisseur would enjoy a more complex fragrance with unusual ingredients. A gardener might enjoy floral essences.

"Another way to choose a fragrance is to consider color. Are they someone who wears bright, happy colors? They will probably enjoy that type of fragrance. Someone who is monochromatic and wears avant-garde fashions will probably enjoy a fragrance that is more minimal and chic."

MIRROR, MIRROR

Does appearance give any clues to the fragrance someone might enjoy? Han believes it does: "Generally speaking, fair skin pairs well with light, clean fragrances or simple florals. The more olive complexion you have, the easier time you will have selecting more complex and full fragrances. Some skin chemistry is naturally sweet, so choose something fresh and crisp to balance it out. If you tend to turn things powdery, try wearing fragrances with wood notes and resins."

The Fragrance Foundation says skin type affects the way a fragrance smells on a person. Those with oilier skin may find the fragrance interacts with the oils to create a more intense scent. Dry skin does not retain fragrance as long as oily skin, requiring more frequent applications.

Blondes with fair skin will be happiest with long-lasting multifloral creations. Their skin is often dry, causing fragrances that are too subtle to evaporate rapidly.

Brunettes usually have medium to dark skin which contains natural oils, allowing scents to last longer. Dramatic Oriental scents are often favorites.

Redheads have fair and delicate skin which may be incompatible with fragrances that have predominant green notes.

The sense of smell is not as sharp in the morning, so The Fragrance Foundation recommends wearing upbeat or "bright" scents at the beginning of the day to sharpen the senses. Once you have awakened your senses, choose fragrances that correspond with your mood, fashion or the occasion.

FOR THE SEXES

According to Chandler Burr, who writes "Scent Notes" for the New York Times, "All serious scent art is unisex." The unisex idea is typified by Byredo Perfumes, a new unisex collection that originated in Stockholm.

Don't be disappointed if Dad's olfactory sense does not seem to be too sharp. The Fragrance Foundation reports that men have a less-keen sense of smell than women. However, they say, much of this is learned. On a day-to-day basis, women are encouraged to use their noses more, for cooking, floral arranging and creating pleasant interiors. Women also tend to use fragrance products from a younger age and more frequently.

Norwegian perfumer Geir Ness, creator of Laila fragrance for women and Geir fragrance for men, created separate perfumes for the sexes because of what he thinks men like on women and women like on men. His tagline for Laila is "the essence of Norway," and for Geir, "the power of Norway."

"Laila is a clean and happy fragrance that will never be heavy on anyone," Ness said during a recent visit to Honolulu to introduce his fragrances at Nordstrom. He named it after his mother, and the label is adapted from her signature. He combines the fresh scent of Norwegian mountain wild flowers and herbs with lavender extract and a drop of vanilla. For Geir, he combined herbs, citrus and lavender.

GOING HIGH-TECH

Sephora stores, which rely on fragrance for a large portion of their business, have tried to take some of the guesswork out of choosing a scent with the introduction of Fragrance Finder by Scentsa. Created by Jan Moran, a fragrance expert and author of the Fabulous Fragrances book series, Moran won a FiFi Award for Technological Innovation from The Fragrance Foundation for Scentsa.

Scentsa uses touch-screen technology on an interactive wall-mounted screen. With the tap of a finger, users can navigate the program to find the 411 on fragrances. The system allows the shopper to find detailed information on the latest fragrances, discover scents from the same fragrance family, view images, run videos or find thousands of reviews on a favorite. Scentsa allows shoppers to search by brand name, fragrance name, fragrance notes, best sellers and new fragrances. There's also a quiz, for fun.

Predictably, there is now a fragrance utilizing all the beauty buzz words, particularly "anti-aging." Ageless perfume says the key to its "high-performance formula" is that it "contains many stimulating ingredients that on contact with the skin produce a dramatic age-lowering effect. This includes an aromatic essence of pink grapefruit, antioxidant-rich pomegranate, jasmine, mango and soft musk," the company wrote in a press release. The jury's out on that one, but if you want to try, it's now available at the Cos Bar in Wailea, Maui, and at www.agelessfantasy.com.

One thing perfumers have not been able to figure out yet is how to make fragrance last and last and last. Once a bottle is opened, it will begin to fade with time. Long exposure to sunlight or extremes in temperature can disturb the delicate balance of the perfume and change its scent.

Of course, that just means we'll have to shop for and test some more scents — then buy them and make them our own.

SENSE MEMORY

A personal anecdote

When I was first dating my husband, my signature scent was Eau d'Hadrien by French perfumer Annick Goutal. I bought it in New York and wore it every day. I stopped wearing it because I didn't return to New York for a few years and it wasn't sold in Honolulu. Years later, when Neiman Marcus made Annick Goutal available here, I bought another bottle.

The first night I wore it, my husband made little sniffing sounds, gave me a wicked Cheshire-cat grin and said, "Isn't that the perfume you were wearing when we first met?"

That did it. I've been wearing Eau d'Hadrien ever since. Ah, the power of scent!