The Power of Smell
For more than 4,000 years, cultures worldwide, such as those in China, India, and Egypt, have harnessed the scents derived from plants and animals for religious ceremonies or healing1–. Yet, the sense of smell is often overlooked and underappreciated. While we have developed a much greater understanding of our other senses and have applied that knowledge extensively, we are still in the process of delving deeper into the olfactory system and harnessing its potential for our benefit.
Scents can transport us to a place or time buried deeply in our memories, allow us to taste and detect flavors, and even affect our mood, emotions, and cognition. When we smell something, the olfactory receptors in our nose can detect these scents because the odorant molecules we inhale attach to specific receptor proteins. This leads to signals being transmitted to the olfactory bulb in the brain, where basic odor information is processed. The processed signals are further relayed to other brain regions for higher-level processing of olfactory information, such as the olfactory cortex and the limbic system. The olfactory cortex plays a critical role in recognizing and making sense of odors, allowing us to distinguish different scents. Meanwhile, the limbic system, particularly structures like the amygdala and hippocampus, receives input from the olfactory cortex and integrates it into emotional and memory-related processes. Linking specific odors to emotional experiences and memories makes the sense of smell a complex and emotionally charged sensory experience.
Over the years, quite a few studies have delved into further understanding the efficacy of functional fragrances on health. For instance, research published in the Journal of Agricultural and Food Chemistry found that inhaling linalool, a compound present in lavender, reduces stress markers in the blood 5. Another study from the Journal of Alternative and Complementary Medicine showed that inhaling a blend of peppermint, basil, and helichrysum improved mental focus and fatigue.
Recently, research findings from the University of California, Irvine, found that inhaling a pleasant aroma during sleep has been linked to a significant improvement in memory. The fMRI results revealed that the group who received the pleasant aromas before bed had improved functioning of the left uncinate fasciculus, an area of the brain linked to memory and cognition. Brain imaging showed a “clear, statistically significant 226% difference on the RAVLT”, a neuropsychological test used to assess various aspects of learning and memory. Additionally, studies have found that certain aromas can play a role in your mood and address various psychological and physical disorders