A scent to remember: odours and memory

Can scents improve our cognitive abilities? A new study published in Frontiers in Neuroscience suggest they can – and by a massive 226% increase.

In the University of California Irvine (UCI) Center for the Neurobiology of Learning & Memory study, participants were asked to use an infuser containing a single essential oil, which released a significant amount of scent for two hours whilst the participants were asleep. Each night, the participants used a different scent, seven in total, and then took a cognitive performance test.

According to the team:

“Imaging revealed better integrity in the brain pathway called the left uncinate fasciculus. This pathway, which connects the medial temporal lobe to the decision-making prefrontal cortex, becomes less robust with age.”

40 a day or just 7?

Previous studies had focused on using up to 40 different aromas twice a day, and had found that this improved the participants’ memory and language skills, eased depression too. However, the UCI team realized that such an approach would not be suitable for those with cognitive impairment. As project scientist Cynthia Woo, explained, her team instead chose just seven scents to be both convenient and practical:

“By making it possible for people to experience the odors while sleeping, we eliminated the need to set aside time for this during waking hours every day.”

Remarkable memories

Our memories are remarkable in that they are often multi-sensory, combining vision, sounds and smells. Often it takes just one of these to trigger a memory, and with specific smells, it can be almost instantaneous. According to Professor of Neurobiology of Learning & Memory Michael Yassa:

“The olfactory sense has the special privilege of being directly connected to the brain’s memory circuits, All the other senses are routed first through the thalamus.“

So the smell of baking choc chip cookies might instantly take you back to baking with your mon, or with your kids. The whiff of a perfume or aftershave or perhaps pipe tobacco can invoke the memory of a loved one. Even ‘generic’ smells such as seaweed on a shore can trigger happy days amongst rock pools or boating adventures long since past.

Aromas and odours can also stimulate the parts of our brains associated with memories and emotional processing. It has long been known that some scents have a calming effect too, such as lavender oil.

Memory, sense of smell and age

The not so good news is that, according to Michael Leon, professor of neurobiology & behavior at UCI:

“The reality is that over the age of 60, the olfactory sense and cognition starts to fall off a cliff.”

If we loose our sense of smell, we lose one of the ways to make sense of our surroundings. This is particularly pertinent for those with dementia. Detecting aromas can give use pleasure, such as the perfume of a rose, or warn us of danger, such as the acrid smell of smoke. Smell also plays a major part in the enjoyment of our food.

As one summary study says:

“Olfactory impairment or disorders can have a significant negative impact on individual nutrition, appetite, safety and overall quality of life and well-being.”

Scent therapy

What the UCI team are calling for is a change in our attitude towards loss of smell, sadly one of the legacies for those with post COVID health conditions.

“Unlike with vision changes that we treat with glasses and hearing aids for hearing impairment, there has been no intervention for the loss of smell.”

As a 2022 olfactory review article reported:

“Although the evidence available is limited, encouraging results were found regarding olfactory stimulation and increased sleep duration, food intake and improved balance.”

How Vytality at Home can help

At Vytality at Home, our aim is to help you and your loved one live independently in your own home for longer.

As a result, we know how the need for personal care hygiene can infuse your home with new smells and unfamiliar products, from skin cream to cleaning products. We also know the comforting effect of familiar scents, from favourite soaps to fresh brewed coffee, flowers from the garden or even a favourite laundry fabric softener.

So we always want to know what you like, so when we deliver our care we can also help your home to retain that unique ‘my home’ aroma. So when the family come to visit, their noses will tell them they are back home too!

Home care in Calgary

Whether regular care, respite care or just to discuss what home care can offer you, contact us for a chat:

539, 5940 Macleod Trail SWCalgary, AB