Secret signals of human sweat (Part 2)

Some scientists are concerned that if someone can synthesize pheromones that cause fear, he can make a powerful army run like a mad cow without shooting.
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Johan Lundstrom, a neuroscientist working at Monell Sensory Research Center in Philadelphia, USA, conducted many tests to prove that women can recognize their sister or sister in one group of people through smell on the body.

However, the women themselves admitted they could not tell the difference between their sister's or sister's smell and the smell on the stranger's body. Many other studies also show that instinct tells women to choose a gene-compatible man for them to be their partners. Genetic compatibility is expressed by the body odor of a man and somehow women are able to feel that compatibility.

For Johan, it is convincing evidence of the existence of pheromones on the human body. 'If you ask scientists if people can broadcast some kind of social message through body odor, 99.9% of them will answer yes. But if you ask them if people have pheromones they will respond that it is not proven, ' he said.

But the reality will change after it is discovered that some animals use the common olfactory organ to identify pheromones instead of two extra nostrils. For example, a recent test showed that mice detected dangerous pheromones of congeners thanks to some cells at the tip of the nose connected to their olfactory system.

Many studies of the brain also revive the hypothesis that people react to sex pheromones. In a series of experiments, the neuroscientist Ivanka Savic of Karolinska Institute (Sweden) gave some people exposure to androstadienone (derivatives of male sex hormones) and used tomography techniques to monitor activity. of the hypothalamus in the front (the area that handles sexual behavior in the brain).

Ivanka found that androstadienone activates the hypothalamus in gay men and normal women, but has no effect on normal women and men. She then discovered the opposite effect when using estratetraenol (female sex hormone derivative).

Scientists also give evidence that humans release warning pheromones and also react to them. Some psychological tests show that we can recognize the smell of fear. In 1999, psychologist Denise Chen of Rice University in the city of Houston (Texas, USA) gave some volunteers watching comedies and horror movies. She then asked some students to smell the sweat of the movie viewers. More than half of the students recognize people who watch horror movies even though they don't tell the difference between patterns of sweat.

In a similar experiment in 2002, psychologist Dr. Kerstin Ackerl of the University of Vienna (Austria) demonstrated that women were able to detect fear. He asked 60 women to smell the sweat of those who just watched horror movies and psychological movies. The majority of women participating in the experiment confirmed that the sweat of horror moviegoers smelled stronger and more unpleasant than the sweat of psychological movie viewers.

But those studies were conducted with small numbers of people and did not provide quantitative indicators, such as the level of fear of those watching horror movies. To overcome these drawbacks, Lilianne Mujica-Parodi of Stony Brook University in New York decided to investigate the direct impact of the "fear of smell" on the brain.

Lilianne and her colleagues attached sponges to the arms and armpits of 40 parachutists before they made the first jump. After the group of volunteers completed the jump, the experts retrieved the sponges to get sweat. They also conduct interviews to classify people who feel scared when hovering in the air.

Scientists require a second group of volunteers (including men and women) to smell sweat patterns. While the group of volunteers smelled sweat, the team conducted a scan of their brains. When the pattern of perspiration of people who are afraid is given, the brain area that handles the fear of most volunteers flashes brighter than normal. This shows that the brain is able to identify chemicals that cause fear in sweat.

The findings of Johan Lundstrom, Denise Chen, Kerstin Ackerl, Ivanka Savic and Lilianne Mujica-Parodi add much valuable evidence that humans also secrete and react to pheromones like animals. But many people feel that it is still too early to declare victory in the pheromone war.

Johan Lundstrom said that the secret was not fully revealed because of a missing piece. 'I think observing brain activity is necessary, but not enough. I want to see human behavior in terms of behavior when we come into contact with pheromones, 'he said.

To give concrete evidence, scientists must identify, synthesize pheromones and conduct tests to see if they produce any behavioral changes. Only then can we confirm with certainty that human pheromones really exist.

That is a difficult goal. Johan said human sweat contains more than 2,000 chemical compounds. 'Identifying one of those compounds is like blindfolding someone, taking him into a place where there are thousands of steles and asking him to dart at the heart of a beer', Johan notes.

If human pheromones are identified, the scientific community will continue to debate their function. Some functions will be more concerned. For example, what is the voluntary nature of love if secret guys bring sex-attractive pheromone sprays to the point of dating girls? Will the modern weapons of an army work on the battlefield if the enemy uses pheromones to cause fear? Some scientists are concerned that if someone can synthesize pheromones that cause fear, he can make a powerful army run like a mad cow without shooting.

Simon Wessely, a psychiatrist from King's College London University and a medical advisor to the British Army, asserted that this hypothesis is unlikely to be scientifically realistic. In the 1960s, he said, a Massachusetts Institute of Technology team injected some adrenaline into some people to cause fear symptoms. However, these people do not feel afraid when facing pleasant situations. This shows that the surrounding environment plays an important role.

Similarly, Johan also found that women's reactions to androstadienone only became reliable if there was a man in the laboratory. Therefore, it seems reasonable to say that the effects of pheromone are relatively weak and affected by many external factors.