The amygdala is a key “fear center” in the brain. Alterations in the development of the amygdala during childhood may have an important influence on the development of anxiety problems, reports a new study. Researchers recruited 76 children, 7 to 9 years of age, a period when anxiety-related traits and symptoms can first be reliably identified. Using non-invasive magnetic resonance imaging (MRI) scans of brain structure and function, the researchers found that children with high levels of anxiety had enlarged amygdala volume.