Lemon, orange, and five other natural essential oils were part of a test of the relationship between aromas and memory. Researchers from the University of California, Irvine, used the essential oils of rose, eucalyptus, peppermint, rosemary and lavender along with that of the two citrus fruits – all of which have shown some promise in other related studies.
The research study was published in Frontiers in Neuroscience in July 2023.
Cognitive loss is a growing issue among an aging population. Remarkably, the study found an increase in memory when the fragrances were introduced to subjects as they slept.
Participants in the study were older adults between 60 and 85 years of age. They were randomly assigned to either the test group or a control group that was not exposed to any fragrances.
- The test group was exposed to one of the aromas for a two hour period as they slept;
- The aromas were cycled through the week, so they were exposed to each for one night;
- The researchers used a diffuser and essential oils.
The test subjects were given neuropsyhcological assessments, and fMRI scans at the beginning of the study, and after six months.
The brain perceives aromas by bypassing the areas of the brain connected with sleep. That’s why it can perceive the odors without a conscious reaction. Stimulating the sense of smell during sleep is also known to result in deeper and more restful sleep.
The results of the test were dramatic.
- Test subjects demonstrated a cognitive increase of 226%;
- The results were achieved using minimal amounts of the essential oils.
The results held after six months. In addition, after that period of time, the subjects in the control group had experienced an additional decline in cognition – while the test subjects who’d been exposed to the fragrances did not.
The researchers observed improved function in a part of the brain called the uncinate fasciculus. It is believed by many that this area of white tissue, which connects major regions of the brain, is involved with memory and how it is used by the brain in decision making.
As the researchers point out, in addition to being extremely effective, it’s a low-effort form of treatment that actually improves brain health.
Check out our method for making lemon essential oil (which you can also apply to oranges, of course) HERE.