EAST LANSING, Mich. — A research project out of Michigan State University is giving a new meaning to the term "gut feeling," examining how bacteria in babies' digestive systems could be linked to how they experience fear.
Rebecca Knickmeyer, a Michigan State University associate professor in the Department of Pediatrics and Human Development, is part of a team that's been tracking fear responses in babies for the past five years.
The MSU and University of North Carolina, Chapel Hill research team tests infants starting at one-month-old to measure how they react to a scary situation.
“Those behaviors have implications for our long-term mental health. So there's evidence that kids who have really strong negative reactions to new situations, or new people are at greater risk for anxiety and depression later on,” Knickmeyer said.
Microbiome research is still a new frontier for many researchers as new technology makes it easier to zero in on specific bacteria in the body.
“For a lot of years, we didn't have the technology to even look at what microbes were living inside of people. And we certainly hadn't thought about how they might change our health,” Knickmeyer said. “Our hope is that, by learning more about how the microbiome develops and what represents a healthy versus an unhealthy microbiome, we could actually support optimal development and thereby decrease risk for later psychiatric conditions.”
Knickmeyer was first inspired to examine the connection between fear and the gut after reading about the primal connection between animals, their bacteria, and their survival instincts.
“If you think back in time, and you're having to decide if that rustle in the leaves is a predator or not, you know, if you get away from the predator, you survive, if your bacteria get away from the predator, they survive as well. So that's one kind of really interesting possibility. There are others as well,” Knickmeyer said.
Phase one of the team’s research, published in Nature Communications, suggests that the gut microbiome could eventually be a new tool to monitor neurological development.
“We wanted to see whether these relationships between bacteria and responses to new situations, which have been seen in animals, where they are in human infants as well,” Knickmeyer said.
For the research project, families bring their infants in to test their reactions to specific stimuli where their responses are monitored and recorded.
First, the research team tests a baby’s response to a stranger by putting them in a room with a research assistant they’ve never met before. The next trial steps up the fear stimuli by bringing the research assistant back into the room with a Halloween mask.
“We don't actually see any relations between the microbiome and response to a stranger. But we do see a relationship with how kids respond when a research assistant comes in wearing a Halloween mask,” Knickmeyer said.
As infants grow, the bacteria in their bodies multiply as well. Researchers hypothesize that a greater number of bacteria in an infant's gut microbiome could be linked to reduced fear.
Knickmeyer says the study wouldn’t be possible if it wasn’t for the families that have volunteered.
“I know as a parent myself, it's really interesting to watch your kids and to see where they fall. You know, what is a normal variation behavior? All kids are so different. That's one of the things I love about the work,” Knickmeyer said.