"A really big question that, at least I ask myself, is, 'How do we become who we are?'" University of Virginia psychology graduate student Olivia Allison said. New work she is conducting in UVA's Baby Lab is aiming to find an answer to that question.

It is homing in on recently published findings that found engagement in a part of babies' brains when viewing smiling or happy faces predicted more social behavior in toddlerhood.

Last year, Allison, along with Baby Lab director Tobias Grossman, analysed data previously collected at the Max Planck Institute for Human and Cognitive and Brain Sciences in Germany. The data included scans of a forward portion of the brain called the dorso-medial prefrontal cortex and questions posed to parents.

"They brought mothers and their infants into a lab space, and then they put a functional near-infrared spectroscopy cap on the baby's head," said Allison, a graduate student who analysed the data. "It's a noninvasive brain imaging method that uses light to measure brain activity."

The babies, aged 11 months, were shown human faces on a computer screen. Some were smiling and looking directly at the babies. Others were smiling, with averted eyes. Still, others were frowning and either looking at the babies or gazing away from them. The caps measure how much-oxygenated blood is in that region of the brain, which helps show what parts of the brain are functioning when the baby is watching certain things.

Allison said researchers later posed a series of questions to the parents when their children were 18 months old. Those included how often the toddlers interacted at large family gatherings and how much they enjoyed playing with different people.

The analysis, published in the journal Imaging Neuroscience, found a direct correlation between brain activity and ensuing social behaviour.

Today, Allison is in the Baby Lab looking at a neighbouring part of babies' brains with an even younger group of infants.

In late January, 3-month-old Heather, pink-cheeked, cooing and squealing away, arrived with her mother at the lab space in Gilmer Hall to participate in the new study.

After a soothing bottle session, Heather perched on a tabletop held by her mother, Megan Gilmer. They sat in front of a computer screen, watching video clips of moving faces, body parts like feet and legs and scenes.

"We hypothesise that the medial prefrontal cortex is going to have greater responses to the faces than objects, bodies and scenes," Allison explained. "We're doing this study with babies two months to 12 months old. That allows us to see how the social function of the medial prefrontal cortex changes over time across the first year of life.

The research will continue through the end of the year. Allison said parents are welcome to sign up to have their children participate in the study on the Baby Lab's website.