LJWorld.com

Kathy Heeb knows a good Christmas tree can transport a person back in time.

The aroma of pine needles can evoke strong childhood memories of hanging ornaments, spending time with family and unwrapping presents.

"You can hear people talk about the wonderful smell of pine," says Heeb, owner of Prairie Elf Christmas Trees southwest of Lawrence. "As you're growing up, you can remember certain smells. And around Christmas time, there are so many scents in the air."

With so many aromas wafting around only at this time of the year - pine, roasting turkey and particular spices, for example - it's no wonder certain smells just remind us of the holidays.

But the reason our nose can trigger such strong memories is even more basic than that, says John Colombo, professor of cognitive psychology at Kansas University.

Photo by Nick Krug

Aromas associated with the holidays - including scented candles - can evoke strong memories from childhood. Psychologists say smell is a primitive sense that is tied directly to parts of the brain that deal with memory.

Olfaction - that's the professorial term for the sense of smell - is tied closely to memory because of the way our brains are built.

When we breathe in, chemicals that produce odors are pulled past nerve cells in the nose's lining, Colombo says. The olfactory bulb - the portion of the brain that discerns smells - is located directly behind the nose, so he says there's almost a direct path from the air to our brains.

The portion of the brain dealing with smells came about early in humans' evolution, Colombo says, so that helps explain why it can trigger some low-lying memories.

"It's a byproduct of how we're wired," he says.

Other mammals use smells for marking territory, but Colombo says even humans have basic animal-like connections to smell. For instance, newborns can detect their mothers' smells after only a few exposures to her.

Our ability to associate a wide variety of smells to particular people or situations is different from our sense of taste. With taste, our discernment is centered around only four or five different types of taste receptors, depending on how you're counting.

"I think our sense of smell is a lot more differentiated," Colombo says. "Instead of saying (a food) has this much salt or sweet taste, we can pick up a lot more with olfaction."

In the kitchen

Bob Garrett, co-owner of Great Harvest Bread Co., 807 Vt., deals with memory-producing scents year-round.

He says the smell of baking bread - a combination of baking wheat and fermenting yeast - can lure someone in off the sidewalk to buy a loaf. Customers often make a comment about baking bread when they were younger, or about baking cookies with their grandmother.

"There's no time lapse," he says. "When you smell it, you're feeling those feelings. When you smell funnel cakes and cotton candy, you're at the fair when you were a kid."

Michael Levy, owner of Westside Deli & Bistro, 4931 W. Sixth St., has seen similar results.

"When you're in the kitchen and there's a turkey in the oven, or someone makes fudge, that's very thought-provoking," Levy says. "It's almost Pavlovian."

As a restaurant owner, Levy says he frequently thinks about how smells from the kitchen might affect his clientele. Having a kitchen close to the dining area can make customers hungrier, he says.

This time of the year, those aromas are even more important, he says.

"People come to cherish the foods they grew up on," he says. "I think it's always been my theory if you can evoke powerful childhood memories through aroma, that's one of the best ways to do that."

'Nostalgic' candles

For those who want to recreate the holiday scents - but who don't want to lug a pine tree to their living room or fire up the oven - candles offer another option.

Waxman Candles, 609 Mass., sells a lot of holiday-scented candles this time of the year. Popular offerings include pumpkin spice, apple spice, clove, peppermint, frankincense and myrrh and cedar.

"Certain people get really nostalgic," says employee Ashley Stubblefield. "Some people have to have cloves because their mom's kitchen smelled like cloves."

There's also more whimsical options, like fudge brownie and "Santa farts," which has a sweet aroma. But Stubblefield says the candles that make a childhood connection to a customer are the best-sellers.

"I definitely say it's a memory thing," she says. "They pick up a candle and they say, 'It smells like ...' and it's always some memory, like grandma's house or church."