It is important to note that the sense of smell is closely linked to emotions and memories. Smells can trigger emotional memories and associations particular to each individual.<\/p>\n\n\n\n
How Does Our Brain Perceive and Recognise Smells?<\/h2>\n\n\n\n![\"\"](\"https:\/\/masterparfums.com\/wp-content\/uploads\/2023\/03\/actu-octobre-2021-cavite-tete-1024x458-1.jpeg\")
Credits: fondsperfumum.org<\/figcaption><\/figure>\n\n\n\nSmells can have a great influence on our mood, our appetite and even our behaviour. A complex journey through the brain takes place to give meaning to smells.<\/p>\n\n\n\n
Unlike the perception of colours, which involves three types of receptor cells located in the retina, the perception of smells relies on about 400 receptors present in the neurons at the back of the nasal cavity. Each receptor can recognise several molecules and each molecule can activate several receptors, thus creating many possible combinations.<\/p>\n\n\n\n
For J\u00e9r\u00f4me Golebiowski<\/a>, professor and co-director of the transdisciplinary research group Odorants-Odeurs-Olfaction at the Institute of Chemistry: “Perceiving a smell amounts to perceiving a musical chord produced on an organ with 400 keys: the olfactory system is thus formidably complex, since there is virtually an infinity of chords.”<\/p>\n\n\n\nOdorant Molecules<\/h3>\n\n\n\n
As we have seen, smells are made up of odorant molecules that float in the air.<\/p>\n\n\n\n
These molecules are captured by our nose when we inhale, and bind to the olfactory receptors located in the nasal cavity. This is what is called orthonasal olfaction.<\/p>\n\n\n\n
But odorant molecules can also come from what we eat or drink. The odorous products of foods and drinks pass through the back of the throat (pharynx) and rise up to the nasal cavity, where they are intercepted by the olfactory receptors. This is what is called retronasal olfaction. This is why, when we have a blocked nose, or when we suffer from anosmia, we cannot perceive the aromas of what we eat or drink.<\/p>\n\n\n\n
The Interception of Smells<\/h3>\n\n\n\n
Right at the top of our nasal cavity (between the two eyes) is the olfactory epithelium, a thin membrane covered with mucus, also called the olfactory mucous membrane. It contains the olfactory neurons whose role is to:<\/p>\n\n\n\n
\n- capture the odorant molecules thanks to their olfactory cilia (small filaments onto which the molecules attach)<\/li>\n\n\n\n
- recognise the olfactory molecules, thanks to their olfactory receptors<\/li>\n\n\n\n
- translate the chemical message of the odorant molecules into a nervous message comprehensible to the brain<\/li>\n\n\n\n
- send these messages to the olfactory bulb in the brain<\/li>\n<\/ul>\n\n\n\n
There are nearly 5 million olfactory neurons in the human olfactory mucous membrane!<\/p>\n\n\n\n
The Transmission of Information<\/h3>\n\n\n\n
The nervous message is then sent to the olfactory bulb, which is located at the base of the brain, and which is responsible for transmitting olfactory information to the olfactory cortex, found in the temporal lobe: this is encoding<\/a>, the creation of a kind of identity card for the smell.<\/p>\n\n\n\nThe Processing of Information<\/h3>\n\n\n\n
The olfactory cortex processes the olfactory information and links it to our experiences and memories. It is part of the limbic system, the seat of our emotions and instinctive behaviours. This explains why certain smells can generate strong sensations in us, emotions\u2014often unconscious, moreover\u2014because they relate to specific moments of our life that we cannot immediately identify.<\/p>\n\n\n\n
Conscious Recognition<\/h3>\n\n\n\n
It is when the information reaches the orbitofrontal cortex that we become aware of our sensations, analyse them and give them a name. It is this part of the brain that allows us to recognise and identify smells. In perfumers, this part of the brain is very often more developed than in the majority of us, owing to their intensive training in recognising smells.<\/p>\n\n\n\n
In general, the olfactory sensation occurs almost instantly, because the nervous message is transmitted very quickly from the olfactory bulb to the olfactory cortex.<\/p>\n\n\n\n
How Long Does the Recognition of a Smell Take?<\/h2>\n\n\n\n
Smells can have a great influence on our mood, our appetite and even our behaviour. A complex journey through the brain takes place to give meaning to smells.<\/p>\n\n\n\n
Unlike the perception of colours, which involves three types of receptor cells located in the retina, the perception of smells relies on about 400 receptors present in the neurons at the back of the nasal cavity. Each receptor can recognise several molecules and each molecule can activate several receptors, thus creating many possible combinations.<\/p>\n\n\n\n
For J\u00e9r\u00f4me Golebiowski<\/a>, professor and co-director of the transdisciplinary research group Odorants-Odeurs-Olfaction at the Institute of Chemistry: “Perceiving a smell amounts to perceiving a musical chord produced on an organ with 400 keys: the olfactory system is thus formidably complex, since there is virtually an infinity of chords.”<\/p>\n\n\n\n As we have seen, smells are made up of odorant molecules that float in the air.<\/p>\n\n\n\n These molecules are captured by our nose when we inhale, and bind to the olfactory receptors located in the nasal cavity. This is what is called orthonasal olfaction.<\/p>\n\n\n\n But odorant molecules can also come from what we eat or drink. The odorous products of foods and drinks pass through the back of the throat (pharynx) and rise up to the nasal cavity, where they are intercepted by the olfactory receptors. This is what is called retronasal olfaction. This is why, when we have a blocked nose, or when we suffer from anosmia, we cannot perceive the aromas of what we eat or drink.<\/p>\n\n\n\n Right at the top of our nasal cavity (between the two eyes) is the olfactory epithelium, a thin membrane covered with mucus, also called the olfactory mucous membrane. It contains the olfactory neurons whose role is to:<\/p>\n\n\n\n There are nearly 5 million olfactory neurons in the human olfactory mucous membrane!<\/p>\n\n\n\n The nervous message is then sent to the olfactory bulb, which is located at the base of the brain, and which is responsible for transmitting olfactory information to the olfactory cortex, found in the temporal lobe: this is encoding<\/a>, the creation of a kind of identity card for the smell.<\/p>\n\n\n\n The olfactory cortex processes the olfactory information and links it to our experiences and memories. It is part of the limbic system, the seat of our emotions and instinctive behaviours. This explains why certain smells can generate strong sensations in us, emotions\u2014often unconscious, moreover\u2014because they relate to specific moments of our life that we cannot immediately identify.<\/p>\n\n\n\n It is when the information reaches the orbitofrontal cortex that we become aware of our sensations, analyse them and give them a name. It is this part of the brain that allows us to recognise and identify smells. In perfumers, this part of the brain is very often more developed than in the majority of us, owing to their intensive training in recognising smells.<\/p>\n\n\n\n In general, the olfactory sensation occurs almost instantly, because the nervous message is transmitted very quickly from the olfactory bulb to the olfactory cortex.<\/p>\n\n\n\nOdorant Molecules<\/h3>\n\n\n\n
The Interception of Smells<\/h3>\n\n\n\n
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The Transmission of Information<\/h3>\n\n\n\n
The Processing of Information<\/h3>\n\n\n\n
Conscious Recognition<\/h3>\n\n\n\n
How Long Does the Recognition of a Smell Take?<\/h2>\n\n\n\n