A smile. A frown. The faces a child pays closer attention to might offer invaluable insight into their mental health. 

Depression may shape how much children pay attention to emotional expressions – sad or happy faces – and those changes appear to depend on whether the child has a family history of depression, according to a first-of-its-kind study from Binghamton University, State University of New York.

Researchers at the Mood Disorders Institute at Binghamton University study how depression develops in children and adolescents, including how family history and emotional experiences shape the risk for depression over time. Understanding these patterns could help researchers identify children at risk and improve further prevention efforts.

Most of the vulnerabilities that we focus on are still developing during this time period. You can catch things as they're developing, rather than only studying them once they're already there and pretty stable."

Brandon Gibb, director of the Mood Disorders Institute and SUNY distinguished professor of psychology

Tracking attention over time

Previous studies have shown a connection between depression and attention to sad faces, but these effects have been small in nature, and it is unclear whether attentional biases are a cause or consequence of depression. Binghamton's study is the first of its kind to examine how attentional patterns and depressive symptoms in children predict changes in one another over time.

"The real novel piece is that we looked at these transactional relations," said Kelly Gair, a PhD student at Binghamton and lead author of the paper. "Between attentional biases and depressive symptoms, we looked at the way that they were mutually predicting one another across the time points, which is especially novel and hasn't been done before."

The researchers, along with Leslie A. Brick from the University of New Mexico, assessed 242 children and their mothers once every six months over two years. At each visit, children watched pairs of faces onscreen, one neutral and one emotional (happy, sad, or angry) while eye-tracking technology recorded which faces they paid more attention to. 

Children in the study looked at faces conveying different emotions onscreen, and eye-tracking technology recorded where their attention veered. Photo credit: NimStim Set of Facial Expressions (Tottenham et al., 2009).

The results suggest that increases in depressive symptoms may affect attention differently based on a child's family history. When children of mothers with a history of major depressive disorder experienced depressive symptoms themselves, their attention became more drawn to sad faces. 

"For those who are already at risk, the more these children experience depression themselves, the more they lose their ability to pull their attention away from the sad things around them," Gibb said. 

"We know that when you're depressed, it changes what you pay attention to," Gair said. "Our results suggest that these changes may be more long-lasting and may differ depending on family history. One thought is that for children of mothers with depression, who are exposed to more facial displays of sadness from interactions with their mom, these types of facial expressions become even more salient when they experience depression themselves, so their attention becomes increasingly stuck on sad expressions."

Different risks, different patterns

In contrast, when children whose mothers had no history of depression experienced increases in depressive symptoms, they paid less attention to happy faces. 

"In our lower-risk children, what seems to be happening is that experiences of depression are eroding a protective factor, which is how much they pay attention to happy faces," Gibb said.

Going forward, the researchers are following children into adolescence to study how these biases might increase risk for diagnoses of depression as they age.