What the Nose Knows - Avery Gilbert [32]
Physical equipment—size of brain areas, number of nerve cells or receptor types—may be less important than what the brain does with the information once it arrives. For many animals, a smell is a call to action, a trigger for a biologically hard-wired survival response: “scent of lion means flee.” In contrast, human cognitive abilities turn smells into symbols and let us make flexible use of their signal value. When it comes to comparative smell ability, it’s the brain, stupid.
Better Than the Rest
One morning when I walked on my monk’s alms-rounds to collect food, my nose became like that of the most sensitive dog. As I walked down the street of a small village, every two feet there was a different smell: something being washed, fertilizer in the garden, new paint on a building, the lighting of a charcoal fire in a Chinese store, the cooking in the next window. It was an extraordinary experience of moving through the world attuned to all the possibilities of smell.
—JACK KORNFIELD, A Path with Heart
My friend Larry Clark is an ornithologist. I have hiked trails with him as he identified bird after bird by song alone. His skill leaves me awestruck. It’s the same feeling I get when a perfumer talks about a fragrance—he seems to be smelling more than I do, finding notes that my blundering nose doesn’t detect until he points them out. How do olfactory experts accomplish these feats? Are their noses that much better than yours or mine? What does it take to become an expert smeller?
Pure nose-sensitivity is not the answer. The average person probably detects odors at about the same concentration as the professional wine taster. What the expert has are cognitive skills that make better use of the same sensory information. The practiced wine expert can name varietals and tell one vintage from another, just as the trained perfumer classifies a new cologne with ease and zeroes in on its unique notes. The expert’s advantage, in other words, is brain power rather than nose power, and in the regular exercise of these specialized mental skills. Wine experts, for example, routinely make notes as they taste. Experts outperform novices in matching their own descriptions to wines on subsequent tastings. Their mental discipline helps experts avoid a trap called the “verbal overshadowing effect” that can snare novices when the effort to generate a verbal label interferes with the perception of the aroma itself.
The perfumers Robert Calkin and Stephan Jellinek believe their job can be done with only an adequate nose. What makes for professional success is specific mental skills and thought processes. My own research confirms that fragrance professionals think differently. Perfumers, fragrance evaluators, chemists, and sales executives have better olfactory imagery ability than nonexperts from outside the industry. The ability to bring to mind the scent of specific perfumes, and to imagine how ingredients will smell when blended, is central to the job description.
Constant honing of perceptual skills may actually change how an expert’s brain responds to scent. The brain-wave patterns of professional perfume researchers have been compared to those of less specialized workers. When smelling an odor, the pros show distinctive frontal lobe activity in an area known as the orbitofrontal cortex—one that is involved in cognitive judgments. This pattern of brain response in the pros may reflect their more analytic way of perceiving odor. Another study examined brain activity in wine sommeliers and nonexperts, as each group sipped and savored wine samples. The sommeliers had activity in areas associated with cognitive processing (the orbitofrontal cortex again) and in an area where taste and smell information are integrated. In contrast, the nonexperts showed activity in the primary sensory areas and zones associated with emotional response. Practice