Gray Matter Differences Between Healthy and Depressed Adolescents: A Voxel-Based Morphometry Study

Abstract

Background: Major depressive disorder (MDD) frequently begins during adolescence and is associated with significant morbidity and mortality. However, little is known about the neurobiology of adolescent depression. A better understanding of the neurobiology will be helpful in developing more effective preventive and treatment interventions for this highly disabling illness. Methods: Using a voxel-based morphometric method, the study compared gray matter and white matter volumes in 22 adolescents with MDD and 22 age-and gender-matched normal controls. Results: Compared with controls, depressed adolescents had smaller gray matter volume in the frontal lobe and caudate nucleus bilaterally and right superior and middle temporal gyri. However, the groups did not differ significantly on white matter volume. Conclusions: These findings in depressed adolescents are consistent with the previous findings of gray matter abnormalities in frontolimbic areas and the striatum in depressed adults and suggest the presence of these structural changes at the onset of depressive illness.

Subthreshold Depression and Regional Brain Volumes in Young Community Adolescents

“…The GM regions detected here in juveniles with subthreshold depression have been implicated in the pathophysiology of depression in adults and adolescents, [9][10][11]14,29 and altered WM microstructure within tracts connecting these regions has been reported in adolescents with MDD. 37 Also, functional impairments within the reward system have been hypothesized to contribute to the onset of depressive disorders in adolescence.…”

“…This result is in line with other neuroimaging studies in adolescents with MDD that did not report smaller hippocampal volumes either. 9,12 Rather, hippocampal volume reductions in adolescents M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 11 have been attributed to illness duration. 45 Similarly, although studies of pediatric depression have reported reduced amygdala volumes 12 or a decreased volume related to comorbid anxiety disorders, 13 we did not observe smaller amygdala volumes in adolescents with subthreshold depression.…”

“…The differences are more widespread in adolescents with MDD, since reduced gray matter volumes have been reported in frontal, limbic, and striatal regions such as prefrontal cortex (PFC), 9,10 ACC, 11 amygdala, 12 hippocampus, 13 and caudates. 9,14 A sex effect was reported in one study demonstrating smaller nucleus accumbens in girls with depression only, and increased growth of the amygdala during adolescence associated with depression in girls and decreased growth in boys. 15 A further step requires investigating the morphometry on the whole brain and assessing the clinical outcome of adolescents with subthreshold depression in order to shed light on the early brain structure variations involved in such emotional dysregulation and vulnerability to depressive disorders, including vulnerability related to sex.…”

The neural correlates of emotional face-processing in adolescent depression: a dimensional approach focusing on anhedonia and illness severity

“…Fitzgerald and colleagues suggest that the STG, prefrontal, insular, and cingulate regions comprise an emotion-processing network that demonstrates reduced activity both at rest and in response to negative affect in MDD. Structurally, reduced gray matter in the STG was also reported in adolescents with MDD (Shad et al, 2012). These data suggest that alterations in the STG occur early in the course of illness in MDD.…”

Comorbid Anxiety and Depressive Symptoms in Children and Adolescents

“…39 It should be noted that symptom severity was correlated with striatal and dorsomedial prefrontal functional connectivity in that study. 39 Neuroanatomical studies have demonstrated that depressed adolescents have decreased gray matter volumes in the caudate, DLPFC, ACC, and temporal lobe when compared with healthy subjects 40,41 …”