The smell of love, part two

Why do some people smell better to you? A look at how human body odor influences sexual attraction. To read part one of this article click here.

Scent and sentiment
Curiously, remembering a smell is usually difficult -- yet when exposed to certain scents, many people -- of whom Proust is the paragon -- may suddenly recall a distant childhood memory in emotionally rich detail. Some aromas even affect us physiologically. Laboratory researchers exploring human olfaction have found that:

• A faint trace of lemon significantly increases people's perception of their own health.
• Lavender incense contributes to a pleasant mood -- but it lowers volunteers' mathematical abilities.
• A whiff of lavender and eucalyptus increases people's respiratory rate and alertness.
• The scent of phenethyl alcohol (a constituent of rose oil) reduces blood pressure.

Such findings have led to the rapid development of an aromatherapy industry. Aromatherapists point to scientific findings that smell can dramatically affect our moods as evidence that therapy with aromatic oils can help buyers manage their emotional lives.

Mood is demonstrably affected by scent. But scientists have found that, despite some extravagant industry promises, the attraction value in perfumes resides strictly in their pleasantness, not their sexiness. So far, at least, store-bought scent is more decoration than mood manager or love potion. A subtle "look this way" nudge to the nose, inspiring a stranger's curiosity, or at most a smile, is all perfume advertisers can in good conscience claim for their products -- not overwhelming and immediate infatuation.

Grandiose claims for the allure of a bottled smell are not new. In their haste to mass-market sexual attraction during the last century, perfumers nearly drove the gentle musk deer extinct. In Victorian England, a nice-smelling young lady with financial savvy could do a brisk business selling handkerchiefs scented with her body odor.

So it should come as no surprise that when physiologists discovered a functioning vomeronasal organ inside the human nose, it was a venture capitalist intent on cashing in on manufactured human pheromone who funded the team's research. That was in the mid 1980s. Using high-tech microscope probes that were unavailable to VNO hunters earlier in the century, a team led by Luis Monti-Bloch of the University of Utah found a tiny pair of pits, one in each nostril, snuggled up against the septum an inch inside the nose.

The pits are lined with receptor cells that fire like mad when presented with certain substances. Yet subjects report that they don't smell a thing during such experiments. What they often do report is a warm, vague feeling of well-being.

And the olfactory bulb that neurophysiologists couldn't find in the 1930s isn't absent in human brains at all, researchers recently discovered. It's just so enveloped by the massive frontal cortex that it's very difficult to find. This finding, coupled with the discovery of a functional human VNO, has ushered in a new chapter of the story of a human pheromone.