Smell bypasses the thinking brain entirely — which is why a reformulated perfume is a different neurological event, not just a different product, and why some people will spend years looking for a bottle from before 2007.
It happens to all of us. Somewhere between a loved one’s familiar embrace, a garden, or the perfume counter, maybe — is a moment we don’t yet know that we’ll find incredibly sentimental at some point in the future. Scent is, for all intents and purposes, a time machine, taking us back to a specific moment, a specific version of ourselves, a feeling. The moment it imprints itself on our brain is usually unremarkable. But catch a whiff of it years later when you least expect it, and you may find yourself swirling in memories and, even, a dogged pursuit to find the bottle from where it came.
Why we love scents
The olfactory system is, anatomically, unlike every other sense. Signals from smell skip the thalamus — the brain’s relay station, where visual, auditory, tactile, and taste signals are all processed and routed before reaching the cortex — and travel directly to the limbic system, which manages memory and emotion, in two synapses instead of the four to six that every other sense requires.
Donald Wilson, a neuroscientist at NYU who has studied olfactory processing, described this architecture to The Washington Post as the reason smell memories are different in kind from visual or auditory ones: the signal arrives at the seat of emotion before the thinking brain has had any opportunity to categorize it. Scent memories are “experienced as more emotional and more evocative” than other sensory memories, Dr. Rachel Herz, an adjunct assistant professor of psychiatry and human behavior at Brown University and the author of The Scent of Desire, told Live Science.
A familiar but long-forgotten scent can even bring people to tears, she added. This is what researchers call the Proust effect — not a memory of a person or a place, but a return to them, physical and involuntary, triggered by something that bypassed the thinking brain entirely.
How fragrances change
In 2001, the International Fragrance Association began restricting oakmoss — a lichen that grows on oak trees and has, on its own, an inky, anchoring smell of forest undergrowth — after two of its compounds, atranol and chloroatranol, were identified as contact allergens. The restriction affected an entire genre. The chypres, a fragrance family built since 1917, when François Coty released a perfume called Chypre, on the architectural tension between bright bergamot and the dark, earthy weight of oakmoss; oakmoss was not merely one ingredient among many but the fixative that bound and stabilized the others and extended the life of the perfume on skin. Reducing it substantially or removing it entirely was less like adjusting a recipe and more like altering the physics of the thing.
Guerlain’s Mitsouko, in production since 1919, was reformulated twice in response: in 2007, when the restrictions began to tighten, and again in 2013, when Guerlain’s in-house perfumer Thierry Wasser made a more successful attempt, adding lentiscus for the mossy character and heavy, odorless solvents for the longevity the original oakmoss had provided on its own. The 2013 version is a good fragrance. The people who wore Mitsouko before 2007 will tell you it is not the same fragrance — which, neurologically, it isn’t: the odorant molecules that encoded their original memory of it no longer exist in that configuration.
“There’s no such thing as getting a password nearly right,” Luca Turin, a biophysicist and perfume critic, told The Washington Post. “If there’s one letter wrong, the thing doesn’t click. Your grandma’s perfume is your grandma’s perfume. If you smell that exact thing, it will remind you of your grandma, right? There’s no plan B, there’s no approximation.”
Pre-2007 juice
The fragrance community has a phrase for the pre-restriction formulas: “pre-IFRA juice.” On Basenotes and Fragrantica — the two major fragrance forums, where reformulation timelines and batch codes are catalogued with the specificity of archivists — the pre-2007 Mitsouko bottles are a subject of sustained attention. The batch code, printed on the base of the bottle, corresponds to a production year; experienced collectors know which codes predate the 2007 reformulation, and those bottles trade used — sometimes decades old, occasionally half-empty — for considerably more than the current version retails new.
Mathieu Iannarilli, a Parisian dealer specializing in vintage perfumes, told the Financial Times that some of his customers have been looking for specific fragrances for years: “some buyers only wear one perfume. When that is discontinued by a brand, from one day to the next, they find themselves orphaned of their olfactory identity. These people then turn to all possible ways to find their perfume again.”
The search is, almost by definition, approximate. A vintage bottle changes over time; top notes oxidize and fade, base notes deepen and become more tenacious, drifting from the formula that exists in someone’s memory. Saskia Wilson-Brown, who founded the Institute for Art and Olfaction in Los Angeles and has watched many people come in hoping to bottle a specific memory, told The Washington Post what she tells them: “But you just can’t do it. Tempus fugit. Time goes on, and we all die and that’s how it is,” she said. “That’s actually the reason I found perfume very interesting in the first place … because it is so intangible.”
Related on Ethos:
