Composition of gut microbiota associated with infant fear response

Why do some babies respond more to perceived danger than others? According to a new study by Michigan State University and the University of North Carolina at Chapel Hill, some of the answers are in amazing places: the infant’s digestive system. It may be in the system.

The human digestive system has a vast community of microorganisms called the gut microbiota. Researchers at MSU-UNC have found that infants with a strong fear response and those with a mild response have different gut microbiota.

The reaction of these fears early in life-how someone reacts to a terrifying situation-can be an indicator of future mental health. And there is increasing evidence to link neurological health to the gut microbiota.

This new discovery suggests that the gut microbiota can one day provide researchers and physicians with new tools to monitor and support healthy neurodevelopment.

“This early development is a great opportunity to promote healthy brain development,” said MSU’s Rebecca Kunikmear. Nature Communications. “The microbiome is an exciting new target that could be used for that.”

A study of this relationship and its role in the zoophobic response has led Knikmeyer, an associate professor of pediatrics and human development at Human Medis University, and her team to look for something similar in humans. .. It is also important to study how humans, especially toddlers, deal with fear, as it can help predict mental health in some cases.

Fear reactions are a normal part of a child’s development. Children need to be aware of the threats in their environment and be ready to respond to them. However, if you can’t control the reaction when you’re safe, you may be at increased risk of developing anxiety and depression later in life. “

Rebecca Knickmeyer, MSU Institute for Quantitative Health Sciences and Engineering, or IQ

On the other side of the response range, children with exceptionally suppressed fear responses can develop cold, non-emotional features associated with antisocial behavior, Knikmeier said.

To determine if the gut microbiota is associated with the human fear response, Knickmeyer and her collaborators planned a pilot study of about 30 infants. Researchers have carefully selected the cohort so that many factors that affect the intestinal microflora are as consistent as possible. For example, all children were breast-fed and none were taking antibiotics.

Researchers characterize the child’s microbiota by analyzing stool samples and observe how the child reacts when someone enters the room wearing a Halloween mask. The child’s fear response was evaluated using a simple test called.

“We really wanted an experience that both our kids and their parents could enjoy. They were always there and could dive in whenever they wanted,” says Knickmeyer. “These are the things that babies actually experience in their daily lives.”

The researchers put together all the data and found that there was a significant association between certain features of the intestinal microflora and the intensity of the fear response in young children.

For example, children with a heterogeneous microbial flora at the age of 1 month were more afraid at the age of 1 year. The heterogeneous microbiome is dominated by a small number of bacteria, but the microbiome is more balanced.

Researchers also found that the content of the 1-year-old microbial community was associated with a fear response. Responsive babies had more bacteria of some species and fewer bacteria of other species than children who were not afraid.

However, the team did not observe the relationship between the children’s gut microbiota and their response to unmasked strangers. Knickmeyer states that this is likely due to various parts of the brain involved in handling potentially horrific situations.

“Strange people have a social component, so children may have social vigilance, but we don’t see strangers as an imminent threat,” said Nickmeier. Told. “Children don’t consider a mask to be sociable when they see it. It goes into the quick and dirty evaluation part of the brain.”

As part of the study, the team used MRI techniques to image the child’s brain. They found that the content of the microbial community a year later was related to the size of the amygdala, which is part of the brain involved in rapid decision-making about potential threats.

Connecting dots suggests that the microbiome may affect the development and function of the amygdala. This is one of the many interesting possibilities revealed by this new study, and the team is currently working on recreating it. Knickmeyer is also preparing to launch a new inquiry with a new collaboration at IQ and is looking forward to answering new questions.

“There is a great opportunity to support neurological health early,” she said. “Our long-term goal is to learn what we can do to promote healthy growth and development.”