Expert talk : the brain’s behavior when confronted with a smell

Dr. Erwan Poivet, conductor at the Institut Pasteur in the ETOC study assessing the relationship between olfaction and cognition in Covid-related anosmia, explains how the brain behaves when faced with a smell.

Erwan Poivet, PhD in Organism Biology and member of the Perception and Memory Unit of the Institut Pasteur, explains that olfaction is a completely different meaning in relation to other sensory modalities. 

The primary function of the olfactory system is to provide the brain with information about its environment in order to satisfy its vital needs (food, dangers, pleasures, interactions and communication) by activating behaviors determined by olfactory information. But now that the vital needs are more easily met for mankind than in the more distant ages of humanity, the olfaction has become essentially the vehicle of emotional information.

In addition, unlike other senses, olfactory stimuli access almost directly the brain centers involved in both memory, emotions and perhaps even mood regulation. This is why it is very easy to associate a smell with a memory or emotion.

The scientist also points out that many olfactory molecules have a trigeminal property in addition to their olfactory property.

The trigeminal system consists of the trigeminal nerve divided into 3 branches located in the mouth, nose and eyes. This system deals with sensations of cool, hot, pungent, burning and this information contributes to the recognition of a smell. For example, the fresh trigeminal character of mint or the spiciness of pepper helps to define its smell.

The brain will thus receive two distinct but complementary information almost simultaneously via two different nerves (olfactory and trigeminal) and superimpose them.

On the other hand, this is absolutely not the case in the face of smells like vanilla or rose for example, which only stimulate the olfactory nerve and therefore fall within the associated memory and this is even more pronounced when the ingredient is shaped.At the anatomical level, odour information is sent from the amygdala to a brain region located between the two eyes, called the orbito-frontal cortex. It is here that the conscious perception of the smell that will please or displease anyone.


So if it turns out that smells influence our behavior, we do not yet know how and how far they determine us. The emotional smell is therefore a vast subject on which researchers are still working, also looking at the individual’s experience and cultural environment.

You can support scientific research related to perfume and smell, crucial for the future of Parfumerie, by making a donation to the Per Fumum Endowment Fund. Find all the answers to your questions on the website or contact us at

Posts created 55

Begin typing your search term above and press enter to search. Press ESC to cancel.

Back To Top