Our Sense of Smell
In 2004, the Nobel Prize in Physiology or Medicine was awarded to two neuroscientists, Drs. Linda Buck and Richard Axel, for their research into the sense of smell and the olfactory system. Different smells are detected by olfactory receptors in the nose, which activates neurons (nerve cells). Their research revealed how neurons communicate with the olfactory bulb of the brain - for us to be able to identify and remember smells.
Beyond the olfactory bulb, neural signals also flow to other parts of the brain, including the limbic area. The limbic area is responsible for processing feelings, moods and memories, which is why we develop emotional connections with scents1. Scents can influence our moods, transport our imaginations and evoke memories; our sense of smell is perhaps the most powerful and creative of the five human senses.
Science of Scents
The term “aromachology” was first introduced by the Sense of Smell Institute in the 1980s as the 'scientific analysis of olfactory effects on mood, physiology and behaviour'. Aromachology shows how scents can affect our moods and emotions backed by measurable physiological results2.
For example, an electroencephalogram (EEG) can measure the electrical activity in our brain and record the waves in cycles per seconds or Hertz (Hz). When we smell different scents, our brain waves fluctuate and this can affect our moods.
Four of the major brain waves are:
- ‘delta’ waves (the slowest, 0-4 Hz) representing a state of deep dreamless sleep;
- ‘theta’ waves (4-8 Hz) representing a state of deep relaxation and meditation;
- ‘alpha’ waves (8-12 Hz) representing a state of contemplation and creativity; and
- ‘beta’ waves (12-40 Hz) representing a state of alertness and focused concentration3.
Fragrances with Benefits
Based on the concept of aromachology, each of our fragrances has been developed around a single olfactive ingredient that has been scientifically-proven to help relax the body, as well as the mind.
From EEG studies, when rose and sandalwood oils are inhaled, they can help to increase activity of the theta and delta brain waves. These slower frequency brain waves can invoke feelings of relaxation to help calm the mind3.
- Bucks, L. B. (2005) Unraveling the Sense of Smell (Nobel Lecture). Angewandte Chemie International Edition. 44, 6128-6140.
- Herz, R. S. (2009) Aromatherapy Facts and Fictions: A Scientific Analysis of Olfactory Effects on Mood, Physiology on Mood, Physiology and Behavior. International Journal of Neuroscience. 119, 263–290.
- Hema C. R., Revathi S. (2012) A Preliminary Study on Aromatherapy as a Stress Buster Using EEG Signal Analysis. Emerging Trends in Engineering Research. 211- 219.