Saturday, January 24, 2009

Annals of Anosmia 3: The Slow Fade

The media’s enthusiasm for first-person essays on anosmia is driven by the drama of sudden-onset smell loss and the medical mystery of in-born absence of odor perception. What these stories overlook is a far more common experience: the age-related decline in smell ability known as presbyosmia.

The demographics are well-known—on average, smell sensitivity and odor-naming skill decline gradually with age; men are affected more heavily than women. Declines in performance can be detected as early as the fifth decade under laboratory conditions, but in everyday life a person might not notice anything until much later. I emphasize that these trends are group averages and that variation within an age group is large. A given 68-year old may be more sensitive than a given 28-year old. An element of use it or lose it may be in play; for example, many of the great perfumers work successfully into old age.

What causes presbyosmia? Scientific speculation points to cumulative wear and tear on the olfactory system: a lifetime of colds, flu, and sinus infections, along with the incremental impact of minor bumps on the head.

The slow fade of smell with age, although exceedingly common, has not inspired its own genre of first-person essays. This insight hit me the other day when I received an email from a reader. C. Rodney James wrote such a compelling account of his personal experience that I asked him to let me share it here on First Nerve.
Dear Mr. Gilbert:

Finished What The Nose Knows with great interest and more than a bit of sadness as it reminded me of what I have lost. As a teen I had a terrific sense of smell. At seventy it’s virtually gone. The fading, as I would describe it, began about ten years ago, perhaps a bit more. A few odors seem to come and go. I can (reliably) smell cat shit, hot paint when the furnace overheats as it did this A.M. and the odd whiff of the priming mixture used in English and some Mexican .22 rimfire ammunition. It has a distinctive tutti-frutti odor like old-time, public rest-room deodorant—unique in the olfactory arena of ammunition. Bad writers (who have never smelled it) include the odor of Cordite, which smells like many other types of nitrocellulose powders. Burning leaves, if the intensity is great enough is detectable, but little more. That’s about it . . .

University education in the speech and hearing field taught me the dangers of exposure to loud and prolonged noise, and I had the wit to avoid exposure to same. As a result my hearing is still quite good. How unfortunate there seems nothing we can do to protect or conserve the sense of smell. There are no exercises or other regimens we could follow. If there are, or better yet some means of restoring this sense, I am ready to join the line. A similar loss happened to my mother so there is likely a genetic link of some sort.

At times I get what I think you described as a false-smell experience, as when I could clearly detect/re-experience the scent of fresh hay the other day—indoors in frigid weather. Very strange.

If anyone ever comes up with some genuine aroma therapy I hope you will get the word out.

C. Rodney James

Mr. James’s observations on the smell of primers and gunpowder are those of an expert. He has written about firearms and ammunition as well as motion pictures.

The evocative power of smell anchors us in time; the longer we live the more meaningful recalled smells become. Mr. James’ wistful note reminds us all of what we stand to lose as age takes its toll.

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