It was mud season when the real estate agent drove my husband and me up a long driveway to a house in the Vermont woods she was hoping we might buy. The owners had just stepped out, she told us, retrieving a key from its hiding spot and pushing open the door. The house was immaculate. There was no mud in the mudroom—nor were there shoes or jackets or hats. In the hallway bookcase there were only a handful of volumes; in the bathroom, a single towel. Either the owners were the tidiest people in the world, or they were no longer in residence and hadn’t been for quite a while.
And then it hit us. A smell, welcoming, familiar and downright homey. It curled like a beckoning finger, inviting us into the kitchen.
“Oh look,” the agent said sweetly. “The owners must have made a batch of brownies before we came over.”
And there, in a spotless kitchen that showed no signs of daily culinary wrangling, was a pan of brownies, still warm, resting on a rack. It was telegraphing all sorts of happy thoughts directly into my brain: Live in this house, it was saying, and you will always think happy thoughts. You will recall making brownies from scratch with your grandmother, recall her soft body and permanently delighted eyes, and how she taught you to use the cap of the vanilla extract as a measure instead of a teaspoon. You will remember the bake sale in second grade that introduced you to brownies with icing that you could peel off like a piece of sod and lodge on the roof of your mouth. You will remember your own daughter hovering as you added sugar to the chocolate and butter, waiting impatiently to lick the bowl.
I once read a story where the protagonist worked as a “house relaxer,” going around to vacation homes shortly before the arrival of their owners and baking chocolate chip cookies because the mere scent of them lulled the owners into believing that they actually lived there. It was like that with me and the brownies.
Smell is evocative, no question about it. This is because the body’s olfactory system is closely allied with the brain’s limbic system, and the limbic system is where we experience and process emotion. The olfactory system is also connected to the hippocampus, a small, cashew-shaped region of the brain that serves as the gatekeeper of memory. Memories that come through our nose, because they are paired like that, are durable. And since taste travels mainly on the odor molecules embedded in food, it’s the same for what we eat.
It’s no wonder that Proust’s famous madeleine, dipped in lime-blossom tea, brings the narrator back through the years to his childhood, to images that “rose up like a stage set.” The reason smell often triggers a memory from way back is because it’s bringing us back to the first time that smell ever registered. Because it’s twinned with an experience, it’s that much stronger. But not for everyone. A few years ago, researchers at the University of Maastricht in the Netherlands noticed that people who later went on to develop Alzheimer’s disease had a hard time identifying certain smells, such as lemon and cinnamon. They weren’t sure of the connection—was it that the olfactory system itself was impaired or was this a first sign that something was going wrong with the hippocampus, which is the first place in the brain where Alzheimer’s is manifest? Now researchers at Columbia have demonstrated that a simple scratch-and-sniff test can be an early-warning sign.
We didn’t buy the house. The brownies, as seductive as they were, could not overcome our more rational selves. A few weeks later we took a look at a different house and—surprise!—there was a freshly baked loaf of bread sitting in a bread machine. We decided to build our own home.
In our new house, the kitchen segues into the dining area, which segues into the living room. Sauté onions while preparing dinner and you’re reminded of that meal the next morning. Because it’s a tight, superinsulated structure, smells linger, and with them, memories. If you couldn’t tell from the muddy mudroom and the bookshelves that are full to overflowing, our house is in a permanent state of relaxation.
—Sue Halpern’s latest book, Can’t Remember What I Forgot: The Good News from the Frontlines of Memory Research, has just been published by Harmony Books.