The fact that our brain does not prioritize all smells is most likely due to evolutionary factors. Because, if the primitive man smelled the saber-toothed tiger’s biting odors in the dark cave, fractions of a second could mean the difference between life and death.

The corona outbreak has attracted attention to a meaning that is largely ignored in regular medical practice. We’re talking about the sense of smell, and one of the most common Covid 19 effects is a temporary loss of it.

It would be more accurate to use specific compounds to test the first of the twelve cranial nerves, the olfactory nerve, which is responsible for smell and taste perception. The olfactory test should be done separately for each side of the nose, for which olfactory sticks with various smells are available, for example.

The sense of smell, as well as how our brain processes olfactory information, remain intriguing research topics. This is hardly surprising given that the olfactory system accounts for about 5% of the human brain’s mass and allows us to identify millions of different smells. Despite its complexity, researchers at the Swedish Karolinska Institute have demonstrated that this system is remarkably quick in a recently published study. The scientists were able to show that the cells of the olfactory bulb, the brain’s primary processing station for olfactory stimuli, react to odors within fifty to a few hundred milliseconds in a series of studies.

It’s also fascinating that smells that the brain classifies as unpleasant and potentially harmful cause a reaction up to fifteen times faster than smells that are regarded positively. They trigger the motor system, which caused the test subjects to lean back slightly when perceiving them in the trial. The researchers deduced that an odor assessment takes place in the olfactory bulb before a person consciously recognizes an odor as pleasant or unpleasant. Previous olfactory encounters and biological imprints are likely to be important.

As a result, the olfactory brain prioritizes the processing of smells linked with potential danger. This pattern is found throughout the animal kingdom and, in evolutionary terms, is thought to have functioned to quickly begin a defense or escape response. Because a detour through consciousness would certainly result in a delay, which, depending on the situation, could be catastrophic, this process operates naturally. Fractions of a second might decide between life and death if the primitive man smelled the sabre-toothed tiger’s biting exhale in the dark cave.

In today’s world, olfactory perception has such a significant impact on humans only in unusual circumstances. Scientific evidence, on the other hand, clearly indicates that body odors continue to play a significant part in social contact. It’s quite likely that your nose is involved if you can’t “smell” someone.

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