I've been looking forward to Rachel Herz' book for a long time. I found out about her work on the psychology of smell several years ago, and although I never got around to reading her academic work (published in reputable journals like the American Journal of Psychology and Chemical Senses), I did keep track of her frequent interviews in the popular media. The Scent of Desire is her first book, and tackles a wide range of questions on the relation between emotion and olfaction. From odor-emotional conditioning and olfactive memory to cultural differences in odor familiarity, Herz explains how odors influence our social relationships and mental health.
Smell is both a detector of danger, and a vehicle of desire. As the title suggests, The Scent of Desire is primarily focused on the latter. The author's basic premise is that emotional experience and the sense of smell are fundamentally interconnected: "emotions are to us what scents are to our animal cousins. Smell for animals informs survival in direct and explicit ways; for us its primary survival codes have been transformed, into our experience of emotions" (pp.14-15). Herz merges this Darwinistic perspective with the assumption that our aroma preferences are learned; to illustrate this point, she refers to experimental studies with infants and adults.
Research shows that children are largely indifferent to scents until the age of 8, and that they learn to like the odor of their environment. Perhaps a reassuring conclusion to the author herself, who as a child wondered why she was the only one to love the smell of skunk. But opposed odor preferences are widespread among adults too: as an example, Herz mentions the likes and dislikes of the wintergreen aroma in the US and Britain, where they are associated, respectively, with chewing gum and a medicine from World War II.
Herz promotes the idea that fragrances can help in overcoming anxieties, although she makes it clear that therapies such as systematic desensitization are only partially effective. She also offers practical suggestions for memorizing information: if you're preparing for an exam, for instance, it helps to have an unusual or unfamiliar fragrance with you that you can also take to your test. Just make sure to use different scents in case you're preparing for different exams: you might end up mixing information, and find yourself "thinking of speed limits when you should be remembering rates for asymptotes". (p.85)
I found the first half of the book very informative; insights in psychology and neuroscience are mixed with the odd anecdote, and even a (highly speculative) hypothesis on how anosmia contributed to the untimely death of INXS-lead singer Michael Hutchence. I was fascinated by the author's assertion that olfactive memories are just as good, but not better than recollections linked to other senses. What is distinctive about them is their closeness to emotionality; that said, it's easy to confuse emotional intensity with accuracy:
The emotional potency of odor-evoked memory leads to the false impression that these memories are especially true, and that odors are superior reminders of our past experiences. (p. 69)
In the second half of the book the focus shifts to sensuality, cravings and comfort smells. Aside from the new smell technologies that will change our daily lives in the near future (especially in the realm of security, a hot topic these days), I'm afraid I got a little bored at this point. What is said here can be found in other popular science books as well.
With its roots firmly planted in evolutionary psychology, The Scent of Desire shares much common ground with Piet Vroon's book Smell: The Secret Seducer (1994); to my great surprise, however, Herz makes no reference to the latter at all. I find this omission regrettable, given the obvious parallels between the authors' approach towards the subject-matter (not to mention the blatant similarity between the book titles). Contrary to what the publisher's blurb suggests, The Scent of Desire is not the first work on the psychology of smell, and it certainly doesn't qualify as the "definitive work", as I'm sure the author would plainly admit herself. That said, it's a well-researched and accessible read, and a welcome replacement for Vroon's rather outdated book.
Dr. Rachel Herz is a Visiting Assistant Professor at Brown University, and works as a consultant on the psychology and neuroscience of aromachemical perception. She developed a line of "mood-enhancing" fragrances trademarked under the name Scentology.
The Scent of Desire: Discovering Our Enigmatic Sense of Smell
New York: William Morrow / Harper Collins (2007)
Hardcover, 266 pages
See also: link to a radio interview with Rachel Herz.