The very survival of our species is dependent upon our ability to adapt and learn from our surroundings. This biological neural network is hardwired into each and everyone of us. Even from before we were born. So by the time we arrive in this “new and waring” world, we are innately equipped, yet need to develop the skills necessary to navigate our social surroundings.
So for babies and children, this translates into searching out who they can trust to care for them.
These social signals and clues have been identified in a new study by a group of MIT neuroscientists. They found that sharing food and kissing are a couple of the most important indicators that babies use to determine who they can count on to take care of them. The showing of a strong and mutual relationship between two people that engage in food sharing, kissing and other behaviors that involve sharing saliva are what matter to them most.
The findings from this study suggested that the sharing of saliva is an important cue for babies to gain a sense of understanding about social relationships. Whether about themselves or others.
Rebecca Saxe, the John W. Jarve Professor of Brain and Cognition and Sciences, a member of MIT’s McGovern Institute for Brain Research and the Center for Brains, Minds, and Machines (CBMM), and senior author of the study said, “Babies don’t know in advance which relationships are the close and morally obligated ones, so they have to have some way of learning this by looking at what happens around them.”
Anthropologists have made distinctions between what is referred to as “thick or thin” relationships. The thick being those who are very close socially, like family and those who share a mutual responsibility for child rearing with strong levels of moral and emotional attachment. This group throughout history and across cultures have displayed behaviors more willing to share bodily fluids like saliva.
Ashley Thomas, an MIT postdoc and affiliated with the CBMM, said, “That inspired both the question of whether infants distinguish between those relationships, and whether saliva sharing might be a really good cue they could use to recognize them.”
Thomas went on to say, “ The general skill of learning about social relationships is very useful. 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 experiment involved researchers observing babies ( 8.5-10 months ) and toddlers (16.6-18.5 months) and their interactions between actors and puppets. They first watched the puppet share an orange with the actor. Then they tossed a ball back and forth with another actor.
The babies were observed a while after the puppet who sat between the two actors showed signs of distress.
The research team noticed the babies would look back at the one actor who shared the food with the other and not the one who played catch with the ball. The researchers hypothesized the babies would look first at the one who was expected to help. They were referencing another study which showed when baby monkeys cried, the other members of the troop always looked to their parents in expectation of stepping in and doing something.
The MIT team of researchers found that the children were more likely to look at the puppet who shared the food with the actor to do something when they displayed stress. Not the other actor who shared the toy.
In a second experiment, they observed the children watching a video that had an actor place her finger in her mouth then into the mouth of the puppet. Or place her finger on her forehead and then onto the forehead of the puppet. In this case, after the actor showed signs of distress, again the children were more likely to look towards the actor who shared the saliva with her finger to the puppet as a call to action.
An interesting fact, was that the first experiment took place right before the lockdowns happened. Families who participated would come to the lab in Cambridge and after the lockdown they would perform the experiment over Zoom. They are happy to have had the research data prior to the lockdown. But believe the results would be the same even though the pandemic raised concerns over hygiene. They thought all the talk about hygiene during the pandemic would have affected the children’s thinking.
Looking into future studies, the team would like to do similar ones from various cultures with different family structures. They are thinking of using a fMRI to determine what brain regions are activated in making the saliva-based decisions.
The human brain is conditioned to use much of its energy to keeping us safe at all times. In social relationships, and at an early age, it will involve the coordination of many brain regions into making this possible. Even as adults, when we aren’t actively involved in formally teaching our children. They are learning from their immediate surroundings… they have to. They can’t help it because it’s a survival instinct. That’s why as parents it’s so important to demonstrate a safe and trusting home by showing signs of love and affection to each other. Especially, when in the presence of the children. They see it, know it, and will ultimately be effected by it for a lifetime.
-A Balance Brain is a Better Brain for a Happier Life-