Floating trough the clouds upon a revenue of $3.5bn a year, the perfume industry has infected us with the shopaholic syndrome: we cannot get enough of these scents. From oud to floral, eau de toilette to cologne, essential oils to candles, shampoos to beard oils, we are surrounded by scents! These scents however, stimulate receptors in our nose as General Odorants.
There's also a specialized category of odorants called Pheromones that play a major role in the formation of social and sexual behaviors in animals. They are known to bind to the specialized receptors present in the Vomeronasal Organ (VNO), commonly known as the Jacobson's Organ.
Although, originally identified by Fredrick Ruyisch, a Dutch Botanist and an Anatomist in 1703, the VNO's description is accredited to a Danish surgeon, Ludwig Jacobson. He had described a variety of its structures existing in mammals in 1803 and even publicly denying its presence in humans.
However, in 1891, M. Potiquet made some contradictory statements suggesting the existence of VNO in humans. Till date, the presence and functions of VNO in humans is highly debatable.
So, how does the VNO work in animals?
The VNO, consisting of specialized olfactory sensory cells (esthesiocytes), is found antero-inferior to the nasal septum.
When a pheromone is detected, it binds to these VNO receptors or sensory cells.
Upon activation of the VNO receptors, a signal is sent to the Hypothalamus to release Gonadotropin-releasing-hormone (GnRH).
GnRH acts upon the anterior Pituitary triggering it to release Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH)
FSH & LH acts upon the gonads (testes and ovaries) to release Testosterone, Dihydrotestosterone, Estradiol and Progesterone
In many species, pheromones are required to even trigger ovulation! However, in humans, as a majority of our sex is non-reproductive, the need for pheromones lacks purpose. We may have a VNO but upon evolution, it has mutated to be non-functional. The VNO present is absent of receptors.
In fact, genetic evidence even suggest the lack of genes coding for the VNO receptor proteins and ion channels. The genes have undergone Transduction (mutated and non-functional), rendering the VNO, vestigial.
So why are the perfumers selling us Pheromones when we don't even have the pathway to recognize pheromones??!
Simple answer is SEX. The $3.5 bn industry is selling SEX, which causes a huge spike in Dopamine. It doesn't matter if one has access to sex or not, it is the possibility of having sex that is the major drive for a dopamine release.
The fascinating results of this research predicted a higher release of Dopamine if the Reward had a 50% probability as opposed to a 100% or even 25% and 75%.
For many humans, sex is the ultimate reward that one can obtain. It is in anticipation of this reward that you see a dopamine spike in the Ventral Tagmental Area (VTA).
Here's something interesting to note, this is the same dopaminergic area of the brain that lights up when one eats chocolate or even snorts cocaine.
Of course, the neuromarketing of perfumes is such that dangling sex as a possibility in front of a person, causes a huge spike in dopamine and in turn raises the sale of the product.
To add to the narrative of sex sells, a majority of these perfumes are marketed in a heteronormative fashion suggesting the man's prerogative to demand sex and even hinting on the sociocultural beliefs rooted in pseudoscience that suggest women are slaves to their biology, thus slaves to the pheromones men wear and would be obligated to dangle sex as a reward in front of you, men.
I'm sorry straight men, if this article disproves all the work you and your fragile ego have put in to become alpha males (now, here's another concept I'd love to disprove it's existence in the human world).
So, what are we smelling?
A majority of the scents out in the market that state the involvement of a pheromone, be it Androstenone (male pheromone) or Androstenol (female pheromone) have their bases rooted in animal physiology, specifically animals such as boars.
When humans smell pheromones as they are marketed as, we just smell general odorants, and we categorize them on a spectrum from pleasant to unpleasant.
Some hold memories, perhaps the scent of grandmom's cookies or the scent of the first rainfall of the year on scorching hot soil (mitti attar) or even the combination of smells one identifies from their initial sexual encounters.
But pheromones? Well, we aren't a slave to them.
Bercík, J., J. Gálová, and A. Pavelka, The use of consumer neuroscience in aroma marketing. Wageningen Academic Publishers books. 2021. ISBN: 978-90-8686-376-1
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