On a continuum to anxiety disorders: Adolescents at parental risk for anxiety show smaller rostral anterior cingulate cortex and insula thickness.

Background: Having a parent with an anxiety disorder increases the risk of anxiety symptoms and anxiety disorders during the lifespan. Moreover, childhood and adolescence anxiety disorders and symptoms have been linked to a range of brain structure abnormalities. However, to date, no study has investigated brain anatomy in adolescents at high risk based on parental anxiety disorders and in adolescents with an anxiety disorder but without any treatment or therapy.

Methods: Anatomical images from magnetic resonance imaging of 68 adolescents with anxiety disorders without any treatment (N = 20), at risk for anxiety because of their parents' anxiety disorders (N = 21), and comparison youths (N = 27), were analyzed using Freesurfer.

Results: Compared to comparison group, smaller cortical thickness of the rostral anterior cingulate cortex and of the insula was observed in anxious and at-risk groups; smaller amygdala volume was observed in the anxious group only.

Limitations: The age range studied is large (10 to 17 years old). Moreover, this study is cross-sectional. Since adolescence is one of the biggest periods of cerebral reorganization, longitudinal follow-up of these youths would be necessary.

Conclusions: Smaller rostral anterior cingulate cortex and insula cortical thickness appear to be cerebral markers of the risk of developing an anxiety disorder in adolescence. The reduction of the amygdala volume seems to be linked to the onset of the disorder.