Senior Mikaela Overton adjusts the stage she used for her research, where she tracked infants’ responses to a short skit to study the social judge­ments they formed. Hannah Niemeier | Col­legian

It’s not every psy­chology research project that starts with dec­o­rating onesies for the par­tic­i­pants, but it’s dif­ferent when the research sub­jects are 6 to 24 months old.

In prepa­ration for her research project on infant social judg­ments, senior Mikaela Overton met with her adviser, chair­woman of psy­chology Kari McArthur, to iron “Baby Sci­entist” onto the gifts she planned to give the sub­jects of her exper­iment.

“We as a department like to support the areas that stu­dents really want to research,” McArthur said. “It’s really an inter­esting idea, looking at the devel­opment of the child’s moral compass in its early foun­da­tions: Are they set that early in life? It’s an explo­ration of important ques­tions in child devel­opment.”

Overton planned her summer research project, funded by the LAUREATES program, with McArthur, who was inspired by a visit to the “baby lab” at Yale Uni­versity.

There, researchers Karen Wynn and Paul Bloom explore social and moral devel­opment in infants. In a ground­breaking study pub­lished in the influ­ential science journal Nature, they set up an exper­iment to test babies’ social judgment: How early in life can infants rec­ognize when others are helping or hurting each other?

The Yale study found that “pre­verbal infants assess indi­viduals on the basis of their behavior toward others,” and con­cluded these assess­ments may lay the groundwork for moral thought and social eval­u­ation. When researchers set up a sce­nario where a “helper” assists a “climber” char­acter up a hill and a “hin­derer” knocks him back down, the babies con­sis­tently chose the helpful one.

Overton said she wanted her project to expand the Yale study.

“I added looking at infants’ heart rates before, during, and after watching the char­acters on the stage and while they are choosing the char­acter,” Overton said. “Pre­vious research showed that babies’ heart rates accel­erate when they reject their envi­ronment or are uncom­fortable, and their heart rate lowers when they accept their envi­ronment.”

Overton reached out to mothers through faculty baby announce­ments, preschools, churches, and mothers’ groups in her search for babies from 6 to 24 months, and she ended up with 12 infants and their mothers. In the lab, the child would sit on the mother’s lap before the stage as the researchers reen­acted the Yale climber-helper-hin­derer sce­nario.

In order to match the shifts in heart rate with the infants’ attention to the show, Overton used an eye-tracking software that was not used in a pre­vious iter­ation of the exper­iment at Hillsdale. McArthur con­trolled the eye-tracking software to see how long babies paid attention, and which char­acters they paid attention to.

Sophomore Sydney San Juan, a psy­chology research assistant, said the video software was an expansion on an earlier version of the exper­iment con­ducted by Sarah Milback ’17.

“The big dif­ference between the two projects was that Mikaela used looking-time software to see the baby’s response as the exper­iment is hap­pening,” San Juan said. “It reg­isters how long the baby looks at each shape, so you can tell which shape they prefer.”

San Juan’s role was pre­senting the two char­acters within arms’ reach for the babies to choose which one they thought was “good.”

“My part was going out with the two shapes and asking the baby which shape is good or bad,” San Juan said. “I was behind a curtain so I was blind, but I could see Mikaela’s reaction. More often than not, they chose the good one.”

Though San Juan said the general takeaway from the study was pos­itive — that babies want to pick the helper — the sample size and a few fussy baby sci­en­tists meant that the study’s results were incon­clusive.

“Unfor­tu­nately, we did not find any­thing sig­nif­icant. Some findings were in the direction we antic­i­pated,” Overton said. “With only a sample size of 12, and with some issues with mea­suring heart rate — it was con­nected to their chest, so sometime they would rip it off because they didn’t want it on them. So we couldn’t use some of the babies’ data.”

Even though the findings were incon­clusive, Overton will still be able to present her research in April at the Midwest Psy­cho­logical Association’s con­ference in Chicago, Illinois.

“The most important takeaway is that some aspects of our hypothesis could be found sig­nif­icant, but a lot of the lim­i­ta­tions that we found would just need to be adjusted: a larger sample size, and dealing with fussy babies,” Overton said. “If I was able to do it again, I would be able to control for that. And some babies were tired because it was almost their bedtime, so I would pick a con­sistent time of day.”

McArthur said an under­graduate psy­chology exper­iment can be suc­cessful without estab­lishing sta­tis­tical sig­nif­i­cance.

“Mikaela did a fan­tastic job with the planning and exe­cution of her research, and she deserves credit for that,” McArthur said. “We as a department never grade on whether they find sta­tis­tical sig­nif­i­cance. We grade on the process: Did they execute good science?”

In addition to pre­senting at the MPA con­ference, Overton will present her research on campus during Parents’ Weekend at the Science Sym­posium for science majors’ research.

Overton plans to con­tinue researching child devel­opment during and after graduate school, where she plans to work in devel­op­mental psy­chology with a focus on abused children and children with mental health issues. As for this project, Overton said she hopes others will expand on her research just as she did with Milback’s.

“Mikaela has always wanted to work with kids, and she got to do that with a younger group than she’s done before,” McArthur said. “So that’s just one of many ben­efits to this study, which was a very worth­while endeavor.”