In this issue of JAMA Psychiatry, Luby et al1 report neuroimaging findings from a longitudinal study of 193 youths who were carefully assessed for clinical depression since preschool and underwent neuroimaging multiple times during early adolescence. Using growth curve modeling, Luby and colleagues characterized trajectories of cortical structure as a function of depression. They found that global volume of gray matter, indexed by cortical thickness, declined more steeply in adolescents with more severe depression. Given that the age range modeled here is characterized by a decrease in volume of gray matter that is posited to reflect synaptic pruning, this finding suggests that synaptic pruning is particularly aggressive in individuals who have experienced symptoms of depression.
Ian H. Gotlib, Sarah J. Ordaz. The Importance of Assessing Neural Trajectories in Pediatric Depression. JAMA Psychiatry. 2016;73(1):9–10. doi:10.1001/jamapsychiatry.2015.2453