Richard Axel and Linda Buck won the 2004 Nobel Prize for their research on how the brain interprets odors. These pioneering scientists found that about 3% of our genes are dedicated to remembering and recognizing about 10,000 different odors, using olfactory receptors.
These receptors are found on cells in the upper part of the nose and they work to detect odor molecules when they are breathed in. Each cell type has only one type of receptor, and each receptor can detect only a few odors.
Information about odors in the environment is then sent to the brain, where a pattern is formed. This means that, even if we encounter a particular smell many years later, we can recognize the pattern of distinct odor.
There are hints in the research, that humans, much like many animals, receive lots of information about each other through our sense of smell. Pheromones (odors released from the body) can be sent through the air and cause physical or emotional changes in other people.
For example, in a study conducted in 2005, gay men who were given anonymous samples of sweat were found to prefer the scent of other gay men. And, heterosexual men were found to fancy the odors of women. Another interesting study conducted by Dr. Martha McKlintock in 1998, found that the menstrual cycles of women living together, tend to synchronize as a result of chemicals released from sweat glands.
If you have a pet dog or cat, you will observe how many of them will present their rear to you or other animals. Cats also sniff each other’s neck when they are checking each other out. A raised tail in one cat, and some rear-end sniffing by the other, usually signals that the friendship is progressing nicely. A female dog on- the- other- hand, will often present her hind end to approaching males when she is ready to mate.
However, if humans do possess a strong odor signaling system like other animals: what problems might perfumes, deodorants and fabric softeners be causing, to finding the right mate?
Phantosmia is an olfactory hallucination which causes you to detect smells that are not there. The word phantosmia comes from Greek and literally means “phantom smell.” These olfactory hallucinations can occur, however, as a result of various brain disorders like schizophrenia, epilepsy, or migraines, and other reasons.
Most people who experience these phantom smells, tend to experience unpleasant odors, which may resemble the smell of rotten eggs, a wet dog, or severe body odor. Some people dealing with this condition may lose lots of weight, as the phantom odors can impact the pleasure of eating
AROMATHERAPY ACROSS TIME
The Egyptians, the Ancient Greeks, and the Romans made use of aromatic herbs as part of religious practice, beauty regimes, and as medicine. The Egyptians, also, were known to put globs of perfumed fat upon their heads, and as the fat melted it would cover their skin and hair providing sun protection and release a beguiling aroma.
During the Middle Ages in Europe, bathing took a bit of a nosedive, because the Church objected to the nudity of the process. In monasteries, monks were urged to perform their ablutions whilst clothed. Many moralists thought that a biannual bath was quite sufficient.
To counteract pongs, fragrant herbs and rushes were strewn across the floors, which would release aromatic aromas when walked on. Clothes too would often be sweetened with roses, violets, or orris roots. Sometimes, clothes, people, and animals were “smoked” with fragrant woods and plants.
In the 1970s, essential oils became part of holistic health practices. Science has found some support for such therapies. For example, smelling lavender and rosemary increases free radical scavenging activity and decreases cortisol level in saliva (Psychiatry Res. 2007).
Just like the books say, we really can smell fear. Research funded by the Pentagon (US Defence), found that people can unconsciously detect when a person near them is stressed or scared, as chemicals are released in the underarm sweat.
More evidence that humans communicate by smell, was published in the journal, Psychological Science, which found that humans can not only smell fear but disgust. And, these emotions appear to be contagious.
In conducting the research, 36 women who sniffed “fear sweat,” opened their eyes wide in a scared expression. Those, however, who smelled sweat from disgusted men, scrunched their faces into a repulsed expression.