Adam’s Journal
There are certain smells that conjure a specific time or place for me. That scent that comes with an electrical storm takes me to the New Hampshire lake where I used to spend summers as a child. The aroma of maple-scented coffee brings me a picture of my wife as she makes her way back to bed each morning to do a crossword puzzle before confronting the day.
Is it just me, or is there a special link between our noses and our memories?
Dr. Scofield Prescribes
The connection between smells and memory is quite real, and it’s universal. For instance, more than a century ago, the French author Marcel Proust recalled how a bite of madeleine cake and sip of tea transported him back to his youth, “the smell and taste of things remain poised a long time like souls, ready to remind us.”
Since then, neuroscientists have determined that the link between our sense of smell and the brain is quite direct, more so than some other senses. It’s also extremely specific: We each have more than 400 types of olfactory receptors. This specificity helps explain why odors can trigger such precise recollections.
As with most senses, smell diminishes as we age. And research has found that this loss of smell is accompanied by worsening memory and cognitive function.
Specifically, declines in the ability to smell are early symptoms of neurodegenerative diseases like Alzheimer’s and Parkinson’s. And the speed of decline appears to matter. A study from the University of Chicago found that the faster a person lost their olfactory senses, the more likely they were to develop Alzheimer’s.
At least one smaller study suggests that training a person’s nose might help to counter some of the symptoms associated with dementia. A 2021 study of dementia patients found that smell training improved depression and helped participants remember words faster. Another study in 2022 found that seniors with depression experienced diminished symptoms following several months of smell training.
So, you’re probably asking, what is smell training?
From what I’ve read, it’s like a daily workout for your nose. Experts recommend finding a handful of strong-smelling household items and sniffing each of them for 30 seconds or so every morning. You want to avoid caustic things – coffee and spices are good; bleach, not so much – and mix them up.
Over time, this can often improve your olfactory senses. Like everything in your body, the more you use them, the better they’ll function.
If you’re really feeling adventurous, you can try your own version of an experiment published in Frontiers in Neuroscience in 2023. There, researchers saw memory improvements in a small group of adults aged 60 to 85 who were exposed to a collection of different scents using odorant diffusers for two hours each night while they slept.
If it proves out in larger studies, this could offer an easy and affordable way to enhance memory for older adults. And just imagine what it could mean if it worked similarly for students cramming for finals!
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Dr. Hal Scofield is a physician-scientist at the Oklahoma Medical Research Foundation, and he also serves as Associate Chief of Staff for Research at the Oklahoma City VA Medical Center. Adam Cohen is OMRF’s senior vice president and general counsel. Send your health questions to contact@omrf.org.
