The Science Behind Why Incense can Change your Mood and Improve Wellbeing
Have you ever wondered how exactly a flower has a scent, how we can smell that scent, and why it’s so evocative?
Our sense of smell is one of our most ancient and primal senses. crucial to our survival, it has played a critical role alerting us to danger and guiding us to food. As we have evolved, this sense has become more than a survival tool. Our sense of smell deeply resonates with our emotions, memories, and even our social behaviour.
This article will explore the biology of our sense of smell, how it affects our emotions, and why this is such an essential aspect of human experience.
How We Smell Things
If you like science, here’s a quick outline of the anatomy of the Olfactory System:
The sense of smell is regulated by the olfactory system located in the nasal cavity. It’s a complex system that consists of three main structures: the olfactory epithelium, located at the in the upper part of the nasal cavity; the olfactory bulb, located at the base of the brain; and the olfactory cortex, located in the temporal lobe.
In the upper part of the nasal cavity, the olfactory epithelium contains specialised sensory cells called olfactory receptor neurons, which detect odour molecules in the air. These cells are unique because they have cilia, or hair-like projections, which are coated with odour-binding proteins. When odour molecules bind to these proteins, they trigger a cascade of events that ultimately generate an electrical signal.
Once the electrical signals are generated, they are sent to the olfactory bulb located at the brain’s base. The olfactory bulb processes the signals from the olfactory receptor neurons and transmitting them to the olfactory cortex, located in the brain’s temporal lobe.
The olfactory cortex is where the signals from the olfactory bulb are ultimately processed and integrated with other sensory information to create our perception of smell. Interestingly, this is also where the emotional and memory-related aspects of our sense of smell are processed. This proximity of the olfactory cortex and the memory and emotional centre of the brain means that our sense of smell has an immediate and powerful relationship with our memory and emotions.
The Coding of Odor Information
One of the unique features of the olfactory system is that it can detect and process a huge number of different odour molecules. Estimates suggest that humans can detect more than one trillion different odours. This is possible because the olfactory system uses a combinatorial code to encode information about individual odour molecules. In this code, each odour molecule is detected by a combination of olfactory receptor neurons, with each neuron sensitive to multiple different odour molecules. By combining the signals from these different neurons, the brain can generate a unique pattern of activity corresponding to each odour molecule. It also allows the olfactory system to detect and discriminate a huge number of different odour molecules with remarkable precision.
The Emotional Aspects of Smell
While the primary function of our sense of smell is to detect and discriminate different odour molecules, it has also been shown to have a powerful impact on our emotions and behaviour. This is partly because the olfactory system is closely linked to the limbic system, the brain region responsible for emotional processing and memory formation.
Studies have shown different odour molecules have different emotional connotations. For example, the lavender is associated with relaxation and calmness, while the scent of oranges is associated with happiness and energy. Similarly, the smell of rotten eggs is associated with disgust and aversion.
These emotional associations are mediated by the connection between the olfactory cortex and the other brain regions that process emotions, such as the amygdala and hippocampus. This allows odour information to be integrated with other sensory information, as well as any emotional and memory-related associations, to create a multifaceted perception of smell.
The Memory-Related Aspects of Smell
In addition to its emotional impacts, our sense of smell is also closely linked to memory formation and recall. This is because the olfactory system is directly connected to the hippocampus, the region of the brain critical for forming and recalling long-term memories.
Studies have shown that smells can trigger vivid memories of past experiences, even more so than other sensory cues such as sight (like photographs) or sound. This is likely because odour information is processed directly in the olfactory cortex, which is closely linked to the hippocampus.
The link between smell and memory is particularly strong for emotionally charged experiences. For example, the smell of a particular perfume or cologne may trigger memories of a loved one or the smell of a specific food may evoke memories of childhood experiences.
The Social Aspects of Smell
Our sense of smell also plays an important role in social behaviour. Research has shown that humans can detect and discriminate individual scents, some of which are very subtle and act as signals of identity, social status, and even reproductive potential.
For example, studies show that women are more attracted to the scent of men who have different immune system genes than their own. This is thought to be an evolutionary adaptation to increase genetic diversity in offspring and enhance immune system.
Our sense of smell plays a role in social bonding. Many animals, including humans, engage in grooming behaviours that involve the exchange of scents to strengthen social bonds and promote cooperation within groups.
This complicated and multifaceted sense of smell is crucial in our emotional, memory-related, and social experiences. Our ability to discriminate between a huge number of odour molecules can trigger powerful emotional and memory-related associations and even act as signals of identity and reproductive potential. As research in this field continues to advance, we are likely to gain a deeper appreciation for the important role that our sense of smell plays in the human experience.
The Importance of Smell in Daily Life
Because our sense of smell is essential to our daily lives, being responsible for the flavours detected in food, the fragrances we enjoy, and the warning signals that alert us to danger, the loss of our sense of smell, known as anosmia, can have a profound impact on our lives.
Anosmia can also lead to social isolation and depression, as the loss of the ability to detect smells can make it difficult to connect with others and enjoy daily activities.
Think then of how we can purposefully use scent to enhance our lives. Research has shown that certain scents can have therapeutic effects. For example, lavender has been shown to have a calming effect, while peppermint can help to increase alertness and focus.
The Importance of Understanding Smell
The study of our sense of smell, or olfaction, is a growing field of research. As our understanding of the biology of olfaction continues to improve, we are realising the important role that scents play in our daily lives and overall well-being.
This research is leading to new therapies that specifically target our sense of smell to treat many conditions.
A deeper understanding of the connection between smell and emotion also has important implications for mental health and well-being. For example, certain scents may alleviate anxiety and depression and to promote relaxation and stress relief.
Given our growing understanding of how chemically produced fragrance can have a negative and toxic effect on our health, this is even more reason to make use of the natural scents of nature found in essential oils and naturally produced incense. These can have a profound effect on our health and well-being.