A new study has found that a key brain structure that regulates emotions does not work in the same way for preschool kids in depression as compared to their healthier counterparts.
The new research at Washington University School of Medicine in St. Louis measured the differences using functional magnetic resonance imaging (fMRI).
For the study, scientists studied 54 children ages 4 to 6. Before the study began, 23 of those kids had been diagnosed with depression. The other 31 had not. None of the children in the study had taken antidepressant medication.
While they were in the fMRI scanner during the study, the children looked at pictures of people whose facial expressions conveyed particular emotions. There were faces with happy, sad, fearful and neutral expressions.
It was found that in the preschoolers with depression, all facial expressions were associated with greater amygdala activity when compared with their healthy peers.
"The findings really hammer home that these kids are suffering from a very real disorder that requires treatment," lead author Michael S. Gaffrey said.
The researchers say the findings could lead to ways to identify and treat depressed children earlier in the course of the illness, potentially preventing problems later in life.
The study has been published in the July issue of the Journal of the American Academy of Child and Adolescent Psychiatry.