My cats often appear convinced that I am handling something they need, and they are wrong. "It's just tomatoes," I tell them, after I've opened a can. They don't believe me. And sometimes, to convince them, I oblige them. I let them sniff my can of tomatoes or beans or artichokes or whatever it is that isn't cat food. Rather than turn aside, however, they sniff, sniff, sniff! Just long enough for me to get a little impatient with whatever mysterious, extended thought process they are experiencing. They are interested, even intrigued, if not a bit let down.
I feel I am doing them a favor. I'm helping their brains grow, I think. If I had young children, I would try to train them to recognize different smells, for the same reason.
When I was an undergraduate, we were taught that adult brain cell growth was impossible. Hah! We now know that there are two brain regions that
can grow new nerve cells. One is the olfactory bulb, your smelling apparatus, and the other is a zone in your hippocampus, a memory-cementing area.
In both areas, neural stem cell development proceeds similarly, in that this neurogenesis requires the right stimulus. Stress hormones like
cortisol squelch the process. In other words, continuous, long-term stress doesn't just feel rotten, it causes brain damage. Short-term stressors like
exercise on the other hand stimulate brain cell growth. Like exercise, learning new smells stimulates nerve cell development in the olfactory bulb,
which is part of your brain. And there are good reasons why you might want to strengthen your sniffer.
In fact, people are developing various smell tests to help with early diagnosis. A couple years back, a much-popularized study suggested the ability to smell peanut butter could be used to diagnose Alzheimer's, for example. This test still needs refinement, but peanut butter is less expensive than a 3,000 dollar PET scan, and it is more delicious.
This research troubled me. I used to joke, "I don't smell good." Schizophrenia and dementia affect my family, too. Though I feel unscathed, I want to stay that way.
Maybe it was the years spent in a lab with vats of pyridine. This is hateful stuff. I tried desperately to find any solvent besides pyridine that would
dissolve my two reactants without producing a side-reaction. No luck. I was stuck using pyridine. Besides causing liver cancer and sterility, it reeks
like the turds of Satan and made me retch if I wasn't very careful with hood venting. I also was required to use loads of sulfurous reducing agents
in doing antioxidant research. (This was usually beta mercaptoethanol, the same stuff that is used to warn us of otherwise odorless gas leaks, and
compared to the pyridine, it was almost pleasant.)
Could my working with these smelly chemicals have burned out my smeller? Is that even possible? Friends discussed odors I could not detect. Wine notes they found remarkable stayed mute to me. So did suspicious odors in the fridge, according to Tim. This makes you feel...socially insecure! The studies linking anosmia to neurodegeneration added yet another layer of worry for me.
Then a really worrisome study came out in 2014. For whatever reason--they don't know the mechanism--loss of smell is strongly correlated to all-cause mortality. They scored 2,918 adults for their ability to smell five odors: rose, leather, orange, fish, and peppermint. People with the the worst scores were most likely to die in the next five years. (They statistically corrected for unhealthy behaviors that knock out your ability to smell, like smoking and heavy drinking.) People with intermediate scores were moderately more likely to die, and people with the best scores lived the longest. But what rocked everyone's boat about this particular study was that this simple smell test proved a more reliable predictor than standard biomarkers of health, like the presence of cancer, lung disease, cardiovascular disease, stroke, diabetes, and liver disease. Oh dear!
The authors concluded that loss of smell did not cause mortality, but that it was a "canary in the coal mine" signaling some other unknown degenerative process. Another more recent article also points out that loss of the sense of smell is linked to a malfunctioning immune system, at least in mice. Something is going on here. We need to listen to our noses.
So by now, you probably are wondering: Can training your odor awareness reverse this process? What if you were to choose from a random assortment of scents, blindfolded, on a daily basis, and quiz yourself on what you were smelling? Can we strengthen our smell cognition?
Yes. "Olfractory training" or smell therapy is now being used for people with anosmia with some good success.
And could this make us healthier? That answer is up in the air along with those smells. What if we woke up and really smelled our coffees? Inhaled the
odor of our meal appreciatively before chowing down? It can't hurt, in any case, to try it. I like therapies that can't hurt, and might help.
I have not been deliberate about it, but I've been testing myself a little bit off and on, for a few years now, when it occurs to me, and certainly not every day. When I think about it, I'll pick up some bar soap, essential oil, or a candle, blind, and quiz myself. What does this smell like? Even with my extremely lazy attempt at smell therapy, I have good news: I smell good again!
Perhaps my meditating has also helped. I tell people that I have been sitting 20 minutes a day for almost three years now, which means I actually manage
to do it every other day. In between having distracting thoughts, which are normal, I notice everything. Smells, the rise and fall of my breath, the
stupid itch on my butt, everything. Lately, I find I am intensely aware of homey scents, dinner cooking, piney woodsy air, and even the previously
mute notes of wine are starting to speak to me. I don't know how this happened, but I think it is a good sign. I certainly am enjoying the richness
of my new sensory world.
If you want to try your own smell therapy, I wouldn't go overboard with exposing yourself to scents. I think it's important that we don't continuously bathe ourselves in a new smell, such as scent diffusing plug-ins, candles, perfume, and incense. When a signal is continuous, you tune it out. It becomes invisible, meaningless. Remember my continuous exposure to the hateful pyridine. If you are going to train yourself, I'd use brief, intermittent encounters. Then pair your encounter with a conclusion: if this smell had a temperature, or a color, what would it be? Is it cool, warm, earthy, fruity, citrusy, rank, woodsy, flowery, or what? Does it paint an image for you? Your conclusion will engage the memory center of your brain, as well as the olfactory region. Why not stimulate both brain cell growing zones, at once?
I'd love to know what you think.