Freshly cut grass, bread fresh from the oven or a new car air freshener. Some smells produce astonishing sensations that are even hard for us to describe.
Some even transport us back to our childhood. But that's not their only advantage. A team of researchers at the University of California at Irvine has discovered that exposure to different smells – or aromatherapy – can help the elderly improve their memory.
The research, the results of which were published in the journal Frontiers in Neuroscience, examined how the memory abilities of elderly people exposed to different scents at night for six months changed, and found that their memory abilities improved significantly and remarkably. Despite being a preliminary study on two different groups, aromatherapy during sleep demonstrated a cognitive increase of 226%.
This project tested men and women aged 60 to 85 with no memory problems. Each person received a diffuser and seven cartridges containing unique natural oils. Participants in the control group received only smaller quantities of the oils. Each evening, before going to bed, the older participants put a different cartridge in their diffuser, which was activated for two hours while they slept.
“When a fragrance wafted through the older people's bedrooms for two hours each night, memories were triggered,” the researchers noted. What's more, the participants admitted to sleeping better.
Researchers say their work could help prevent dementia. Their findings transform the well-known link between smell and memory into a simple, non-invasive technique for stimulating memory.
Environmental enrichment
As well as influencing different states of arousal, certain fragrances have been shown to alleviate symptoms in people suffering from various ailments and disorders. And they've even been shown to give little ones a helping hand in vocabulary exercises. This is what we call environmental enrichment.
Earlier research had already shown that exposing dementia patients to up to 40 different odors twice a day for a defined period of time increased both their memory and language skills, alleviated depression and improved their olfactory abilities.
“The reality is that above the age of 60, the sense of smell and cognition start to fall off a cliff,” said Michael Leon, professor of neurobiology and behavior and member of the CNLM, in a university statement.
To adapt the experiment and find a simple, accessible tool for improving the condition of people with dementia, the researchers decided to use just 7 scents: rose, orange, eucalyptus, lemon, peppermint, rosemary and lavender. “It's unrealistic to think that people with cognitive impairment could open, smell and close 80 bottles of scented products a day. It would be difficult even for those without dementia,” said Leon.
“The sense of smell has the special privilege of being directly connected to the brain's memory circuits,” said Michael Yassa, research associate at the James L. McGaugh Chair in Neurobiology of Learning and Memory. “All other senses pass through the thalamus first.”
According to the researchers, the next step will be to study the impact of this technique on people diagnosed with cognitive loss.
Sleep and smell
Another finding was that participants in clinical trials reported sleeping more deeply. And that is that what is perceived by the sense of smell can influence how long it takes to fall asleep and how long you stay asleep. “Smell and sleep have a bidirectional relationship,” reports in Sleep Foundation. “This means that sleep can affect the sense of smell, and the sense of smell can affect sleep.”
Moreover, from this institution specialized in rest, they assure that there are different odors that can promote sleep, help wake up in the morning or influence dreams and memories.
