Did you know that the nose plays a vital role in the human experience? Not only is it integral for maintaining the respiratory system, but it also plays a big role in other body functions as well – lending aid to one’s sense of taste, immune function, and hearing.
The System Behind Smell: What is the Olfactory System?
However, what the nose is most well known for is its contribution to a person’s ability to smell. Consisting of the nose and the nasal cavities, the olfactory system helps people with identification through scents. They can determine whether something is safe to eat or whether something has gone bad. They also allow humans to identify whether something is hazardous.
The nose is also important in how they contribute to smell, emotion, and memory. For many humans, smells are often associated with experiences. This is through the power of associations. When people perceive a specific smell, the neural pathways send signals to the olfactory bulb in the brain. These signals are projected to the amygdala and the hippocampus, which are two regions in the brain that direct memory and emotion. When the nose and the brain work together in that fashion an association is created in the mind. As a result, negative or positive feelings and emotions become tied to that specific scent.
A Quick Overview of Pheromones
One type of subtle scent that involves the olfactory system are pheromones. These are chemical substances produced by an organism which acts as a silent form of communication. Much like the broader category of scent mentioned above, pheromones can create specific associations that are positive or negative.
While pheromones are most commonly associated with the animal kingdom, humans are also affected by them as well. Scientists have identified four types of pheromones that could potentially affect human behavior: releaser pheromones, signaler pheromones, primer pheromones, and modulator pheromones. Releaser pheromones elicit a behavioral response and are most commonly seen in animals. Signaler pheromones act as identification cards. In other words, contextual information -- where someone has been, what they have eaten, where they belong – can be derived from this type of pheromone. Primer pheromones are closely tied to physiology and development, particularly of the reproductive nature. Finally, modulator pheromones affect mood and emotion. In current studies pertaining to pheromones and humans, scientists have focused on primer pheromones and modulator pheromones as experiments have shown that these two pheromones might have overlapping functions.
Primer Pheromones: Playing the Long Game
Studies on primer pheromones have often revolved around two sub topics: the body’s secretions and obstetrics and gynecology (OB-GYN for short). The first topic has its roots in animal studies as a lot of what we know comes from those results. For example, in a bee colony the queen bee is able to send out primer pheromones – known as the Queen mandibular pheromone – in order to regulate and govern the colony. This pheromone goes well beyond simple messaging or communication. Instead, a queen bee’s usage of the Queen mandibular pheromone means they can incite loyalty of worker bees to the hive, prevent other queen bee candidates from forming, and even prevent the reproductive organs of worker bees from growing.
Another example can be found in mouse studies. Through studying the urine of male mice, there have been three key effects that have been noted. The first is the Vandenbergh effect, where exposure accelerates puberty in female mice. The second is the Bruce effect, which can inhibit pregnancy. Finally, there is the Whitten effect, where it enables mating cycles to sync up. All three effects show that pheromones can affect biological development and function.
The clues left from these studies have led to a focus on how primer pheromones might affect reproductive development in humans. While no firm conclusions can be drawn just yet, some studies have already shown how primer pheromones can affect women’s menstrual cycles. One example of this is how cycles can be shortened or lengthened through pheromone exposure, and another example would be how proximity with other women can lead to the synchronization of women’s menstrual cycles.
Modulator Pheromones: Neuropsychological Tuning
Modulator pheromones are quite interesting because the areas they affect tend to be subtle. As mentioned earlier, these pheromones affect emotion and mood. This where pheromones and attraction tend to overlap as the exposure of pheromones through the olfactory system can create positive memories and responses. While the vomeronasal organ (VNO for short) – the organ that detects and processes pheromones in other humans – is underdeveloped, recent studies have challenged the notion that this organ has lost its function. Instead, some scientists now think that this organ may work with other parts of the body to process pheromones.
In a study on relationships and couples, psychology professor Harald Euler noted that many women admitted to seeking out their partner’s aroma. This implies that the power of scent can bring about a sense of security, attraction, or familiarity. Pheromones and scents can act as bridges to greater intimacy because of the memories they trigger or because of the memories they elicit.
Another group that has been the focus of many studies have been babies, mothers, and the relationships they build due to pheromones. Some researchers believe that the natural odors and smells from both the mother and the baby plays an important part in creating a positive relationship between the two. This form of attraction enables a strong foundation for the mother and the baby to familiarize with each other. The olfactory cues from the mother’s body odor and breast milk can help the baby recognize the mother as someone safe and slowly build the foundations for the formation of that memory. Other studies have shown that the presence of these pheromones can help the release of oxytocin, which is a hormone that reduces stress and creates feelings of comfort.
While the process of how pheromones work in these contexts are rarely on people’s minds, these results show how important of a role they play in subtly affecting emotions and memories.
What’s the Consensus on Pheromone Research Anyways?
Although a lot of research on pheromones is still in its early stages, many scientists believe that humans do react to pheromones. While people may not absorb and process pheromones in the same ways as animals do, some preliminary research has already shown that there are effects on human body and behavior. These experiments have encouraged people to include pheromones in different products like fragrances and oils in hopes of replicating similar results. After all, everyone wants to pack a punch through first impressions – and the first whiff of someone’s smell is a powerful way to go about it.