Research suggests that if human pheromones do exist, scientists have not identified them yet.
Living things often communicate through chemical signals called pheromones. Pheromones elicit social responses in members of a species. Different species use pheromones to attract mates, mark their territory, or activate defenses. Though humans rely more on visual and vocal cues, there are theories that pheromones make an impact on mate selection in humans.
New information tells us that we may not understand all that much about human sexual behavior. Previous information has told us that humans have two pheromones, androstadienone (AND) and estratetraenol (EST), that affect attraction. AND is for males, and EST is for women.
However, a more recent study seeks to debunk these claims. Researchers have found that AND and EST do not affect humans in a way that sex pheromones are expected to.
To test how AND and EST affect human behavior, researchers gathered a number of heterosexual male and female participants. In order for the researchers to confirm that AND and EST are indeed human pheromones, the participants would have to respond in a certain way to certain stimuli. AND and EST would have to affect mate perception in the participants if they truly were human pheromones.
The researchers merged images of a man and a woman's face to create a gender-ambiguous face. They then exposed the participants to the “putative” pheromones as well as a control scent and asked them to rate the attractiveness of the face.
The researchers exposed the male participants to EST, and the female participants to AND. If the putative pheromones had been actual pheromones, the male participants would have perceived the face as female. The female participants, meanwhile, would have perceived the face as male. However, neither sex produced the expected reaction.
Another test had participants rating the attractiveness of a face belonging to the opposite sex. The participants did not find the faces any more attractive when they were exposed to the putative pheromones. In both tests, exposure to the pheromones and the control scent did not generate different results.
Researchers thus concluded that AND and EST are unlikely to be human pheromones, because they do not affect mate perception. Leigh Simmons, lead author of the study, claims that AND and EST are no longer “worth pursuing” as human pheromones. However, Simmons believes that humans do indeed have pheromones, but scientists haven't identified them yet.
Of course, there are contentions to these findings. Behavioral psychologist Wen Zhou at the Chinese Academy of Sciences is critical of the experiment's design. Zhou is doubtful that the gender-ambiguous faces were truly ambiguous, and thinks that the pheromones were somehow compromised in the study. Behavioral neurologist Martha McClintock, meanwhile, thinks that the researchers expected the pheromones to behave too simplistically. She says that the pheromones trigger a more subtle reaction compared to the reaction that the researchers expected.
In any case, there is a need for more research on the matter. Scientists are still unsure if human pheromones exist at all, so there is a need for more experimentation and documentation.
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