Sharon Douglass loves the way different scents make her house smell. She also likes the way they make her feel.

Douglass, who lives in Bath, uses scented flameless candles, plug-ins and other good-smelling products in her living room, bathrooms and hallway.

“The house is old, and when it rains it can get a little musty, and it just kind of helps with that,” Douglass said. “And you know, a lot of scents are calming, and I just kind of like that.”

Douglass, a massage therapist, chooses scents based on her moods. In the end of the house where she does massages, she uses a lot of lavendar, which is known for invoking relaxation.

“People walk in and they just comment on how fresh or nice the house inside smells,” she said.

Douglass is one of the growing number of Americans who use scents as a kind of accent in their home, just as you would use a throw pillow or a particular color of paint on the wall.

According to the National Candle Association, about 80 percent of all candles sold in the United States are scented. Consumers are using them both to make themselves feel better — vanilla to relax, sandalwood to sleep better, etc. — and to set a mood that will affect visitors in their home.

There’s even a relatively new category joining fruits and florals that’s especially popular this year, called “Fantasy.” This category includes scents such as mango, pineapple, melon, gardenia, jasmine and coconut. The idea is that these scents will whisk you away — in your mind, anyway — to a tropical beach and soft ocean breezes.

Because smell is such a visceral sensation, it’s the quickest way to change someone’s mood or behavior, says Dr. Alan Hirsch, director of the Smell & Taste Treatment and Research Foundation in Chicago. Our sense of smell is linked to the part of our brain that processes emotion.

“It’s part of the limbic system, so your emotions and smell are all intertwined,” Hirsch said. “As a result, people perceive that you are as you smell. If you smell good, they perceive you’re good. If you smell bad, they think you’re bad.

“Similarly, your home is an extension of yourself,” Hirsch continued. “If your home smells bad, it means the residents of the home are bad — not just dirty, but morally bad — and if the home smells good, the residents are good.

“As a result, when you go to visit somebody, the first thing you notice is a smell, and you’ll get an impression of them, which is very hard to change.”

The latest trend in odor research is “functional odors” — using odors for particular effects. Businesses are grabbing onto this idea and pumping scents into stores and hotels to get their customers in the mood to spend their money.

But this concept can also apply to the home.

Here’s a look at what scientists have found out about different scents and how they can affect your home environment:

• HOME OFFICE OR KIDS’ STUDY ROOM: Hirsch’s group found that a mixed floral smell will improve the speed of learning by up to 17 percent, compared with working or studying in a room with no odor.

• EXERCISE ROOM: The smell of buttered popcorn or strawberries, Hirsch found, makes home athletes burn more calories during the same time period.

Another study found that the scent of jasmine, known for increasing alertness, improves a wide variety of athletic performances, including reaction time. When Hirsch had players for the Chicago White Sox smell jasmine on a wristband before swinging at a pitch, it improved their batting average. In an earlier study, jasmine was also shown to have a positive effect on the performance of bowlers.

• GAME ROOM: A study funded by the Sense of Smell Institute in New York at Wheeling Jesuit University found that college students playing video games showed significant improvements in their game play when they smelled peppermint, which has been found to improve memory and alertness. They completed more levels, and said the games seemed less demanding.

• KITCHEN: Studies show that people eat less in the presence of green apple, banana and peppermint.

• DINING ROOM: One of Hirsch’s studies, performed in 100 homes in the Chicago suburbs, found that the odor of garlic bread served with a meal increased positive interactions at the dinner table by 8 percent, and cut down negative reactions by 22 percent.

• BEDROOM: To go to sleep faster, fill your bedroom with the scent of vanilla or baby powder.

For a better sex life in the bedroom, use a combination of lavender and pumpkin pie for men (shown to increase blood flow “down there”) or a combination of cucumber and the candy Good & Plenty for women. (Good & Plenty and banana nut bread also had positive effects.)

A researcher at Wesleyan University found that lavender increased the amount of time spent in the deep, restorative phase of sleep. She also found that while it worked on both men and women, it worked better for women,

• WANT TO SELL YOUR HOUSE? Odors can help there too, but not for the reason you think. Realtors have backed off, to some degree, on the suggestion that homeowners bake cookies or fill their homes with some other nostalgic scent to lure potential buyers. They’ve found that some buyers think the seller is trying to cover up something bad with the pleasant odor.

But research shows that some scents can make rooms appear larger.

“We found that the smell of green apple and cucumber makes people perceive a room as larger than it is,” Hirsch said.

He isn’t sure why. It could be that the scents put people into a more positive mood, or that they make potential buyers feel as if they are outdoors, and that translates into a feeling that the room is bigger than it really is.

“Or maybe it works on the parietal lobe, the part of the brain that’s involved in spatial perception,” Hirsch said.

Whatever it is, the same concept is being marketed to companies that make MRI scanners, the thought being that the odors could make patients feel less cramped in the machinery.

Staff Writer Meredith Goad can be contacted at 791-6332 or at:

mgoad@pressherald.com

Twitter: MeredithGoad