Nightly exposure to essential oils significantly enhanced memory and altered brain structure in older adults. A simple 2-hour olfactory enrichment using diffusers improved verbal recall and modified key neural pathways, offering a low-effort, non-invasive approach to support cognitive health and brain ageing.
July 2023 – Frontiers in Neuroscience
Key takeaways
- Scent improves memory recall: Older adults exposed to different essential oils each night for six months experienced a 226% improvement in verbal memory compared to a control group. This boost was measured using a well-established memory test, suggesting that even minimal olfactory stimulation can powerfully support cognitive performance
- Night-time enrichment works effortlessly: The intervention required just two hours of scent exposure during sleep using a simple diffuser. This minimal-effort routine bypassed the need for active participation, making it a practical and accessible approach for cognitive enhancement—especially valuable for older individuals or those with memory concerns
- Brain structure positively changes: MRI scans revealed significant changes in the left uncinate fasciculus, a white matter tract connecting brain regions involved in memory and emotion. This suggests olfactory enrichment may help preserve or restore neural pathways that typically decline with age or neurodegenerative conditions
- A potential tool for healthy ageing: This low-cost, in-home method offers a promising strategy to enhance brain health and potentially delay age-related cognitive decline. Given the link between olfactory loss and neurodegeneration, scent-based stimulation could become part of a broader toolkit for promoting longevity and mental vitality
- Seven essential oils used nightly: Participants rotated through one of seven pleasant essential oils each night: rose, orange, eucalyptus, lemon, peppermint, rosemary, and lavender. These oils were diffused for two hours at bedtime, creating a varied and novel olfactory environment—crucial for stimulating the brain and enhancing memory over time
Read the article at: Woo, Cynthia C., et al. Overnight Olfactory Enrichment Using an Odorant Diffuser Improves Memory and Modifies the Uncinate Fasciculus in Older Adults. Frontiers in Neuroscience, vol. 17, 2023, doi:10.3389/fnins.2023.1200448.