'Chemicals released from babies' turned out to be aggressive to women and obedient to men

Animals produce chemicals called pheromones that secrete them out of the body, promoting changes in the behavior and development of other individuals. However, no scientific evidence has been identified so far that humans secrete pheromones. A research team led by neuroscientist Noam Sobel of the Weizmann Institute of Science reports that they have discovered an odorless compound called 'hexadecanal' released by human females, especially babies.

Sniffing the human body volatile hexadecanal blocks aggression in men but triggers aggression in women
https://www.science.org/doi/10.1126/sciadv.abg1530

Chemical emitted by babies could make men more docile, women more aggressive | Science | AAAS
https://www.science.org/content/article/chemical-emitted-babies-could-make-men-more-docile-women-more-aggressive

According to the research team, hexadecanal encourages female aggressive behavior and slows male aggressive behavior. It was found that humans release hexadecanal from their skin, saliva and excrement, especially babies from their heads. When Sobel et al.'S research team isolated hexadecaneal and put it in a mouse cage, it seems that a relaxing effect was seen on the mouse.

The research team then conducted an experiment in which 126 subjects were asked to play a 'computer game developed to elicit strong frustration and corresponding measurable responses.' Half of the subjects played with a cream kneaded with hexadecaneal on their upper lips, and the other half played with a cream without hexadecaneal.

Subjects had a virtual experience of sharing money while negotiating with an invisible partner. The subject thought he was negotiating with a human, but he was actually negotiating with a computer. However, the negotiations are designed to frustrate the subject, and if the subject shows less than 90% of the total amount in the 'partner's share', the computer will display a bright red letter 'NO!' It was a specification that rejected the proposal.

After that, the subject played a game in which the sound was hit against the opponent under the same conditions. In order to show the degree of aggression of the subject, it was possible to select the loudness of the sound by pressing the button indicating the 'pain level'.

As a result, among the subjects who were sniffed by hexadecanal, 19% of females behaved more aggressively than average, while more than 18.5% of males behaved less aggressively than average. I understand.

In addition, the research team used functional magnetic resonance imaging (fMRI) to monitor the brain activity of the subjects and compared the behavior of the hexadecaneal sniffed and non-sniffed groups. The results showed that an average of 13% of female subjects increased aggression, an average of 20% of male subjects weakened aggression, and hexadecanal had different effects on brain activity between men and women. Females have decreased neurotransmission in the brain region that controls aggression, and males have increased transmission in that region.

From this result, the research team speculates that hexadecanal may be involved in the survival of infants. In mammals, mothers often exert aggression to protect their babies, whereas fathers should strive not to attack their offspring. 'I can't say that Hexadecanal is a pheromone, but Hexadecanal is a molecule that influences human behavior, especially aggressive behavior,' Sobel said.