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Did you know that hotels place vials of fragrant oils on guests’ pillows to help calm them and improve the quality of their sleep? Science suggests that these oils may be effective, and it even suggests that certain scents can help improve your brain and memory while you sleep.
In the July 2023 issue, the researchers The cutting edge of neuroscience They claim that “olfactory enhancement”, or the inhalation of pleasant scents while sleeping, affects brain function, significantly improving cognitive ability and enhancing memory.
How the scientists carried out their study
Of the 43 study participants (healthy men and women aged 60 to 85), 20 received two hours of aromatherapy each night. Seven different aromatic oils were diffused through a diffuser in alternating rooms each night for six months. Compared to the control group, the 20 volunteers’ cognitive abilities improved by 226 percent, as measured by a word list test often used to assess memory.
The exact protocol is as follows:
- Participants brought their own air freshener diffusers manufactured by Diffuser World.
- We have seven types of essential oils available: rose, orange, eucalyptus, lemon, peppermint, rosemary, and lavender.
- Participants were instructed to turn on the diffuser before going to bed and allow the scent to escape for two hours.
- Rotate a different scent every night
- Every night for six months
Although the study was conducted on cognitively intact elderly people aged 60-85 years, it is possible that it may be beneficial for younger groups as well. At the very least, the side effects and risks of sleeping with aromatherapy are very minimal.
The findings support previous research, including a report published in the journal in 2021. Geriatric Nursing Olfactory stimulation could be a “simple and convenient new intervention for relief, maintenance and recovery.” [and managing] Cognitive function and [behavior and psychological symptoms] For older adults with dementia.”
So why is smell so important for cognition, emotion, and general neurological function?
Smell is directly linked to memory
Unlike other senses such as vision and hearing, the olfactory nerve is directly connected to a white matter pathway in the brain (the uncinate fasciculus) and plays a key role in learning and memory encoding. The olfactory nerve is part of the brain’s limbic system, which controls emotion and behavior.
The authors of the July 2023 paper say that this pathway deteriorates with age and the onset of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. In fact, the sense of smell is much like a cave canary, with the bird’s sensitivity to adverse conditions and the resulting death warning miners to quickly flee. Loss of smell can be a warning for the onset of about 70 different neurological diseases and neuroinfections. Traumatic brain injury can also alter or impede olfactory discrimination.
The researchers are quick to point out that olfactory stimulation does not directly affect the areas of the brain that control sleep. But the use of natural scents can deepen slow-wave sleep, they say. Slow-wave sleep is considered “the most restful part of the sleep cycle,” the researchers write. “Fragrances enhance normal sleep and improve abnormal sleep to a similar extent as sleeping pills.”
Meanwhile, the National Sleep Foundation says smells can affect “how long it takes you to fall asleep.” [as well as] Overall quality and quantity of sleep. The unique scent can improve the quality of your sleep, help you wake up in the morning, and even [potentially] It affects dreams and memory formation during sleep.”
Key components of what is defined as “quality sleep” include duration, continuity (how many times you wake up during the night) and the amount of beneficial slow-wave (deep) sleep, which is important for improving memory, strengthening the immune system, repairing bone and tissue, and regenerating cells.
Lavender is the most studied, but other oils are also beneficial
While lavender is the scent most studied for improving sleep, previous reports have also cited compelling benefits from natural oils such as jasmine, rose, Roman chamomile, and even cedarwood, all of which are plant extracts, that are said to help ease anxiety and depression.
In an article published in 2021, Complementary therapies in medicineThe authors reviewed 30 studies on aromatherapy and concluded that the use of aromatic oils has a “statistically significant” effect on improving sleep quality and reducing “stress, pain, anxiety, depression, and fatigue.” In fact, aromatherapy also appears to be effective in controlling acute insomnia, the authors say. And of course, new research shows that the scent of these oils can make users smarter in terms of cognition, memory, and judgment.
The therapeutic properties of natural aromas are not a new concept: the Greek physician Pedanius Discorides, considered the father of pharmacognosy, discussed the medicinal properties of natural vegetable oils in his book The Medicinal Properties of Medicinal Plant Oils. Materia MedicaIt was written in the 1st century. Later, in the 12th century, St. Hildegard, a German Benedictine abbess, composer, philosopher and medical writer, used distilled lavender for therapeutic purposes.
Discover the best ways to use scent
Tens of thousands of Americans could benefit from a scientifically-recognized approach that uses natural scents to improve sleep quality and boost cognition and memory. Sleep disorders are widespread in the U.S. The National Sleep Foundation estimates that more than one-third of adults don’t get the amount of sleep they need. The Centers for Disease Control and Prevention puts the figure closer to 35 percent.
Chronic insomnia and other sleep deprivation are associated with a variety of physical, mental and psychological symptoms. These symptoms include: mood changes and increased irritability, problems with concentration and attention, poor judgment and executive decision making, physiological changes such as impaired brain function and hormone production, weakened immunity to disease, overstimulation of appetite and weight gain, increased risk of diabetes and various dementias, overactivity of the nervous system, chronic fatigue and even premature death. This list also includes a variety of mental illnesses such as increased anxiety, depression and obsessive-compulsive disorder.
Author Rachel Carson once wrote:
The sense of smell has the power to recall memories more than any other sense.
In fact, 21st century science proves her right.
