Instinctively human beings, regardless of their place of origin, can recognize when someone is trustworthy or could harm them, revealed an international study involving experts from the Postgraduate Degree in Psychology from UNAM.

Isaac González Santoyo, researcher of the Faculty of Psychology, specified that possibly this ability aided early humans in social interactions between members of a group.

“Innately, regardless of the sociocultural context where the individual is born, we have the ability to subjectively judge the reliability or the intention to harm you, which could favor the survival and, possibly, the reproduction of the individual”, commented the doctor in Biomedical Sciences from UNAM.

If a person perceives that the face of another is dominant, he will be more cautious when interacting with him; On the other hand, if he perceives that he can trust they will favor more social collaborations.

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Photo: UNAM Global TV.

International work

The study published in the latest issue of the journal Nature Human Behavior emerged as part of an international network called the Psychological Science Accelerator (PSA) and in which experts from all continents participate, with the aim of fight against an imminent problem in psychology: the lack of replicability in research that has had a great impact in the area.

“With 41 countries we made the largest sample that has been carried out of any study that evaluates human behavior, with 11,570 participants from 11 regions of the world”, explained.

The expert explained that this type of investigation they were usually carried out in Caucasians or cultural groups with high socioeconomic income, in which facial perception was reviewed, but there was a question whether these results could be replicated in other populations around the world.

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Photo: UNAM Global TV.

They claim that, for example, People are more likely to cooperate in socioeconomic interactions with individuals whose faces look trustworthy, vote for those with competent-looking faces, and seek romantic relationships with the most attractive. And conversely, those who do not seem trustworthy may be socially less favored.

For this, each of the researchers presented images of 120 faces (60 men and 60 women) from four ethnic groups for people to rate how attractive they appear, dominant, intelligent, trustworthy, aggressive, mean, responsible, social, unhappy, or strange looking.

What they revealed is that in the world human beings, regardless of whether they were born in Africa, Europe or Latin America, they judge similarly the images or the face of others in two dimensions, mainly: reliability and probability of being damaged.

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Shuhei Okawara, 30, owner of the Kamenya Omote mask shop, holds a super-realistic face mask based on his real face, made with 3D printing technology, in Tokyo, Japan, December 16, 2020. REUTERS / Issei Kato

In this work, in addition to González Santoyo, Anabel De la Rosa, Alan Barba-Sánchez, from the Iztacala School of Higher Studies; Elliott Kruse, from the Instituto Tecnológico y de Estudios Superiores de Monterrey, as well as Nadia Corral Frías and Martha Frías Armenta, from the University of Sonora.

Beyond the innate

Despite this consistency in the perception of reliability, This international group found that with the use of an alternative analysis strategy, much more variability in facial perception is observed between countries, for very important social dimensions such as attractiveness, intelligence or responsibility.

Therefore, González Santoyo’s team expanded their studies because found that the Mexican modifies his perception according to another facial characteristic: skin tone.

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Masks based on real people’s faces are displayed at Shuhei Okawara’s mask shop in Tokyo, Japan, December 16, 2020. REUTERS / Issei Kato

This led the researcher university student to investigate what are the characteristics of the shape of the face that would be decisive for making judgments innately as a species, and what are the other components, such as skin tone, which have been learned as socially favorable by the members of a country due to determining historical processes, such as a history of conquest.

“We evaluated whether the change in skin color associated with Caucasian characteristicss learned to a better social hierarchy, is associated with the subjective perception that we have of individuals or if this perception is related to the shape of the face, regardless of skin tone ”, stressed the researcher.

The results of this new phase of research are expected to be published towards the end of 2021 or 2022.


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