For Some Children With Anxiety Problems, Genetics Play a Role
A recent study conducted by researchers at Stanford University’s School of Medicine, and published in the Journal Biological Psychiatry, suggests that children who struggle with anxiety have unusually large amygdalae. This part of the brain is responsible for several intense emotions, including fear. Indeed, scientists refer to this part of the brain as the “fear center.” The study examined 76 kids between the ages of seven and nine, while parents underwent assessments concerning the anxiety levels of their children.
Examining The Brain
The authors of the study used non-invasive MRI scans to examine the brains of the young subjects. Children with larger amygdalae were found to exhibit higher levels of anxiety than other children. Greater connectivity with other parts of the brain correlated with emotion perception and attention was also found in the unusually anxious participants.
What Is The Amygdala?
Most broadly speaking, the amygdala is involved in emotional behavior, learning and motivation. This part of the brain receives input from all five of our senses. It is responsible not only for fear, but also for other intense emotions, such as aggression. It should therefore come as no surprise that dysfunction of, or injury to, the amygdala, can have serious emotional consequences. For example, irritative lesions produced by temporal lobe epilepsy can stimulate the amygdala, causing panic attacks.
Destructive lesions, such as ablation of the amygdala, can have the opposite effect. Such lesions cause animals to become tame and humans to become calm, exhibiting flat emotions. This can result from diseases such as Urbach-Wiethe disease, which results from calcium being deposited in the amygdala. Individuals with bilateral amygdala lesions are incapable of distinguishing different emotions in facial expressions, although they retain the ability to identify faces. The part of the amygdala associated with memory and recognition resides in a part of the brain linked with perception, allowing the brain to create emotionally charged memories.
Formula For Fear
The researchers were even able to develop an equation by which anxiety levels could be measured based on measurements of amygdala volume and connectivity examined by the MRI. Hopefully, this study will contribute to understanding the role certain amygdala circuits play in the neurological component of anxiety, which may lead to safer and/or more effective treatment for those who suffer from this potentially devastating class of mood disorder. Researchers hope that the study may shed light on potential neurodevelopmental origins of excess anxiety, which may itself provide avenues of treatment that may nip anxiety in the developmental bud before it becomes an intractable habit in adults. In the meantime, cognitive-behavioral therapy (CBT) and SSRI medications remain valuable sources of treatment for those who suffer from anxiety disorders.