In what could help better treat young children at risk for anxiety disorders, researchers have found that children with high levels of anxiety may have enlarged volume of amygdala, the "fear centre" in the brain.
Amygdala is an almond-shape set of neurons located deep in the brain's medial temporal lobe that plays a key role in the processing of emotions.
Alterations in the development of amygdala during childhood may have a significant influence on the development of anxiety problems.
Children with high levels of anxiety had enlarged amygdala volume and increased connectivity with other brain regions responsible for attention, emotion perception and regulation, compared to children with low levels of anxiety, the findings showed.
"Our study represents an important step in characterising altered brain systems and developing predictive biomarkers in the identification for young children at risk for anxiety disorders," explained Shaozheng Qin from Stanford University School of Medicine in the US.
The study involved 76 children aged between seven and nine - a period when anxiety-related traits and symptoms can first be reliably identified.
The study appeared in the journal Biological Psychiatry.