Babies can tell who has close relationships based on one clue: saliva

Sharing food and kissing are among the signals babies use to interpret their social world, according to a new study.

Learning to navigate social relationships is a skill that is critical for surviving in human societies. For babies and young children, that means learning who they can count on to take care of them.

MIT neuroscientists have now identified a specific signal that young children and even babies use to determine whether two people have a strong relationship and a mutual obligation to help each other: whether those two people kiss, share food, or have other interactions that involve sharing saliva.

In a new study, the researchers showed that babies expect people who share saliva to come to one another’s aid when one person is in distress, much more so than when people share toys or interact in other ways that do not involve saliva exchange. The findings suggest that babies can use these cues to try to figure out who around them is most likely to offer help, the researchers say.

“Babies don’t know in advance which relationships are the close and morally obligating ones, so they have to have some way of learning this by looking at what happens around them,” says Rebecca Saxe, the John W. Jarve Professor of Brain and Cognitive Sciences, a member of MIT’s McGovern Institute for Brain Research and the Center for Brains, Minds, and Machines (CBMM), and the senior author of the new study.

MIT postdoc Ashley Thomas, who is also affiliated with the CBMM, is the lead author of the study, which appears today in Science. Brandon Woo, a Harvard University graduate student; Daniel Nettle, a professor of behavioral science at Newcastle University; and Elizabeth Spelke, a professor of psychology at Harvard and CBMM member, are also authors of the paper.

Sharing saliva

In human societies, people typically distinguish between “thick” and “thin” relationships. Thick relationships, usually found between family members, feature strong levels of attachment, obligation, and mutual responsiveness. Anthropologists have also observed that people in thick relationships are more willing to share bodily fluids such as saliva.

“That inspired both the question of whether infants distinguish between those types of relationships, and whether saliva sharing might be a really good cue they could use to recognize them,” Thomas says.

To study those questions, the researchers observed toddlers (16.5 to 18.5 months) and babies (8.5 to 10 months) as they watched interactions between human actors and puppets. In the first set of experiments, a puppet shared an orange with one actor, then tossed a ball back and forth with a different actor.

After the children watched these initial interactions, the researchers observed the children’s reactions when the puppet showed distress while sitting between the two actors. Based on an earlier study of nonhuman primates, the researchers hypothesized that babies would look first at the person whom they expected to help. That study showed that when baby monkeys cry, other members of the troop look to the baby’s parents, as if expecting them to step in.

The MIT team found that the children were more likely to look toward the actor who had shared food with the puppet, not the one who had shared a toy, when the puppet was in distress.

In a second set of experiments, designed to focus more specifically on saliva, the actor either placed her finger in her mouth and then into the mouth of the puppet, or placed her finger on her forehead and then onto the forehead of the puppet. Later, when the actor expressed distress while standing between the two puppets, children watching the video were more likely to look toward the puppet with whom she had shared saliva.

Social cues

The findings suggest that saliva sharing is likely an important cue that helps infants to learn about their own social relationships and those of people around them, the researchers say.

“The general skill of learning about social relationships is very useful,” Thomas says. “One reason why this distinction between thick and thin might be important for infants in particular, especially human infants, who depend on adults for longer than many other species, is that it might be a good way to figure out who else can provide the support that they depend on to survive.”

The researchers did their first set of studies shortly before Covid-19 lockdowns began, with babies who came to the lab with their families. Later experiments were done over Zoom. The results that the researchers saw were similar before and after the pandemic, confirming that pandemic-related hygiene concerns did not affect the outcome.

“We actually know the results would have been similar if it hadn’t been for the pandemic,” Saxe says. “You might wonder, did kids start to think very differently about sharing saliva when suddenly everybody was talking about hygiene all the time? So, for that question, it’s very useful that we had an initial data set collected before the pandemic.”

Doing the second set of studies on Zoom also allowed the researchers to recruit a much more diverse group of children because the subjects were not limited to families who could come to the lab in Cambridge during normal working hours.

In future work, the researchers hope to perform similar studies with infants in cultures that have different types of family structures. In adult subjects, they plan to use functional magnetic resonance imaging (fMRI) to study what parts of the brain are involved in making saliva-based assessments about social relationships.

The research was funded by the National Institutes of Health; the Patrick J. McGovern Foundation; the Guggenheim Foundation; a Social Sciences and Humanities Research Council Doctoral Fellowship; MIT’s Center for Brains, Minds, and Machines; and the Siegel Foundation.

Link Original: https://news.mit.edu/2022/babies-relationships-saliva-0120?fbclid=IwAR2BA8gvjkO0Z10zT4F2iw8-pq2kKftNKhK6zsOuXErOiTTZARrQVOPRLVY


Social isolation linked to higher levels of inflammation

Being lonely or socially isolated can negatively affect your wellbeing. There is even research showing that it increase the risk of illnesses such as cardiovascular disease, dementia and depression.

Some researchers suggest that loneliness and social isolation lead to poorer health because they increase inflammation. Inflammation is when your body tells your immune system to produce chemicals to fight off infection or injury. It can also occur when you experience psychological or social stress.

Short-term, local inflammation – such as when you accidentally cut your finger – can be helpful, but having slightly elevated long-term inflammation is associated with poor health. Researchers propose that loneliness and social isolation are linked to this elevated long-term inflammation.

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Qué es soka, el modelo educativo japonés basado en la felicidad

¿Eres feliz cuando vas a clase? Esta es la pregunta que solemos hacer al comienzo de nuestra asignatura Educación para la Felicidad.

Hace cuatro años detectamos un hueco importante en la formación inicial de los futuros profesores de Magisterio en Educación Infantil y Educación Primaria. No habíamos incluido un espacio de reflexión interdisciplinar acerca del sentido de la educación.

Para eso, creamos una asignatura que llamamos Educación para la Felicidad, y uno de nuestros pilares es lo que podemos denominar la Educación Soka.

¿De dónde viene la pedagogía Soka?

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Intellectual humility: the importance of knowing you might be wrong

Why it’s so hard to see our own ignorance, and what to do about it.

Julia Rohrer wants to create a radical new culture for social scientists. A personality psychologist at the Max Planck Institute for Human Development, Rohrer is trying to get her peers to publicly, willingly admit it when they are wrong.

To do this, she, along with some colleagues, started up something called the Loss of Confidence Project. It’s designed to be an academic safe space for researchers to declare for all to see that they no longer believe in the accuracy of one of their previous findings. The effort recently yielded a paper that includes six admissions of no confidence. And it’s accepting submissions until January 31.

“I do think it’s a cultural issue that people are not willing to admit mistakes,” Rohrer says. “Our broader goal is to gently nudge the whole scientific system and psychology toward a different culture,” where it’s okay, normalized, and expected for researchers to admit past mistakes and not get penalized for it.

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Alan Watts – Não vivemos em uma sociedade materialista, é muito pior: vivemos na sociedade das aparências

ascensão do consumismo nos fez pensar que vivemos em uma sociedade materialista. Quando nossa felicidade depende do que possuímos e do que somos capazes de comprar, é difícil não pensar que o materialismo tenha se apropriado de nossa cultura. No entanto, o filósofo Alan Watts pensou que a realidade é ainda pior: ele estava convencido de que nossa sociedade não é materialista, mas idolatra as aparências. E a diferença é substancial.

Na sociedade das aparências, a essência se perde

“Não é correto, muito menos, dizer que a civilização moderna é materialista, se entendermos como materialista a pessoa que ama a matéria. O cérebro moderno não ama matéria, mas as medidas, não os sólidos, mas as superfícies. Beba pela porcentagem de álcool e não pelo ‘corpo’ e pelo sabor do líquido. Construa para oferecer uma fachada impressionante, em vez de fornecer um espaço para viver ” , escreveu Watts.

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¿Nos volvemos adultos a los 25 años? Esto es lo que dice la neurociencia

«Te encuentras ahora en otra etapa. Eres una persona adulta».

A una determinada edad, la sociedad considera que ya tienes la capacidad de asumir ciertas responsabilidades.

¿Pero cómo se fija ese momento en que «nos volvemos adultos»?

No tiene que ver con poder casarse y votar, algo que en muchos países puedes hacer a los 16 y a los 18 años.

Para Peter Jones, profesor del instituto de neurociencia epiCentre, de la Universidad de Cambridge, no podemos decir que hay una niñez y una adultez.

«Lo que hay es un camino», señaló Jones, quien participó este mes en una conferencia sobre el desarrollo del cerebro organizada por la Academia de Ciencias Médicas de Reino Unido.

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