The Science of Smells | How Scents Affect Our Brain

Published on: 27/11/2020

With its links to our emotions and memory, our sense of smell should not be taken for granted.

Whether we are aware of it or not, certain smells bring about certain emotions in us. The scent of your favorite perfume, the aroma of cookies baking in the oven, the smell of freshly-cut grass, or the stench of garbage from the street may have distinct effects on our brain. 

According to Brown University professor Rachel S. Herz, odors affect how we feel and behave in a variety of ways. This is because we have learned to associate these smells with some events in our life, causing it to elicit some sort of response from us. 

Research from Toronto University shows memories triggered by smells tend to be more intense, more vivid, and more emotional. Scientists have a theory that part of the brain that processes smell is directly linked with parts involved in emotion and memory.

How do we smell things?

Smelling begins high inside the back of our nose. There in the olfactory epithelium, which is a strip of tissue, millions of sensory neurons lie. These types of cells called olfactory neurons, send messages to the part of our brain known as the olfactory bulb. This structure at the base of the forebrain is then responsible for relaying the signal to other parts of our brain for additional processing.

The practical applications of scents

Scientists used to believe that the human nose identifies about 10,000 different scents. However, a recent study from The Rockefeller University and Howard Hughes Medical Institute revealed the number is over a trillion. 

With our capacity to distinguish a wide array of scents, there are still these distinct smells that can bring about the same reaction in most people. For example, experts have learned that how a store smells can affect buyers’ purchase decisions. They observed that 84% of shoppers found a pair of shoes more attractive when displayed in a room with pleasant odor than to an identical pair placed in a room with no smell. 

As such, this could be the reason why businesses such as those who manufacture soap, cigarettes, and washing powder opt to add fragrances to their products.

How to use scents to boost your mood

Nowadays, there are a lot of products like perfumes, aromatherapy candles essential oils, and room fresheners that offer various benefits for our well-being. While their effects may vary, fragrances are made up of volatile chemicals, which can be effective in boosting our mood when smelled.

Among the most helpful scents to improve concentration are peppermint, lavender, and strawberry. The smells of citrus and cinnamon meanwhile, are said to stimulate our brain and increase productivity. 

How some scents can help you sleep

If you are trying to get more sleep, the smell of lavender, vanilla, and roses may help. In fact, there have been clinical trials reported by Maryland University researchers wherein lavender was proven to help reduce anxiety, stress, insomnia, and post-operative pain. They have found that lavender can be beneficial in slowing down the activity of the nervous system and that patients were able to get improved relaxation and better quality of sleep. 

As we learn to appreciate our sense of smell, we realize our nose does not only help us identify the odors around us but it's clearly connected to our emotions and memory.