Scent!
Worldwide, the COVID 19 virus affected millions of patients’ ability to smell – and the symptom persisted in some, months after the infection passed. The pandemic put a spotlight on this spectrum of olfactory impairment. Anosmia is the clinical term for an inability to perceive smell. Parosmia turns pleasant smells like coffee and cologne into stenches for some (the “fortunate” ones perceive foul smells as pleasant.) In phantosmia, people hallucinate smells.
Totaro’s personal experience and sensitive profiles of fellow-anosmics and parosmics make it clear that a sense of smell is integral to peoples’ emotional well-being — depression strikes a good third of the people who have lost their ability to smell. The neuroscientist Oliver Sacks has written of “a woman transfixed by grief when she couldn’t recognise the smell of her own baby; a man’s faltering explanation of the deadening effect of anosmia on lovemaking; and a passionate home cook who could not enjoy the tantalizing smell of onions frying – or of her pots burning on the stove.”
Smells warn us of spoiled food or gas leaks, and other threats in our surroundings. Even when olfactory loss is temporary, it cannot be dismissed as trivial.
Smell is the most understudied of our five senses. The author introduces us to the work of pioneering olfactory researchers such as Linda Buck who identified the family of genes that allows humans to detect and distinguish smells. Buck’s fundamental research, for which she won the Nobel Prize for physiology in 2004, has laid the groundwork to understand certain diseases characterized by a loss of smell.
Gathering evidence shows that conditions like Alzheimer’s and Parkinson’s are associated with an early loss of smell and the symptom is linked with schizophrenia and dystonia. So, in the future, the smell test may be part of routine health checkups, particularly for older people, the author writes.
Researchers have figured out some of the biological mechanisms that lead to covid-related smell loss. The virus does not infect odor-detecting nerve cells, but attacks cells that play a supporting role in the olfactory system – so regeneration is a possibility.
But no doctor can tell you how long this disruption of smell will last or even if you will recover. Though there is no cure for anosmia, a technique known as smell training – regular, mindful sniffing of basic aromas such as those of rose, clove, eucalyptus, and lemon – has been demonstrated to help some patients with olfactory loss. Patience is key, writes Tatoro.
On a recent trip to Puglia, that authors saw a religious procession on the streets of a small Italian town, complete with a parishioner carrying an old incense burner. Tatoro writes that the scent of frankincense and myrrh brought back childhood memories of attending Mass with her grandmother. And she wept in gratitude, for her newly functional nose.
html. pdf