The MRI of a Person with Generalized Anxiety Disorder: What Does It Look Like?
The MRI of a Person with Generalized Anxiety Disorder
Most people react to dangerous or frightening situations with some degree of fear and anxiety, but people with generalized anxiety disorder experience symptoms of anxiety when no real threat exists. They usually worry excessively and overreact to situations that aren’t stressful for most people. Since the symptoms people with generalized anxiety disorder experience involve the brain and nervous system, it’s not surprising that researchers have looked closely at the brains of people who suffer with this condition. What does the MRI of a person with generalized anxiety disorder show?
MRI Imaging and Generalized Anxiety Disorder
When researchers have done MRI imaging of people with generalized anxiety disorder, the area of the brain that looks most abnormal is a structure called the amygdala. The amygdala consists of two almond-shaped areas located deep within the brain. These small, but important structures are not only important for processing emotions, they also communicate with another portion of the brain called the hypothalamus, which, among other things, is responsible for activating the sympathetic nervous system.
The sympathetic nervous system sets into motion the so-called “fight or flight” response, which pumps up the blood pressure, heartbeat, and breathing rate so that a person can respond quickly to danger. For example, if a giant poisonous snake crawls into your bed, your body would quickly turn on its fight or flight response – so you could make a quick getaway before being bitten.
The Amygdala in People with Generalized Anxiety Disorder
When looking at the MRI of a person with generalized anxiety disorder, researchers have found changes in the appearance of the amygdala. In one study where researchers scrutinized the MRIs of children and adolescents with generalized anxiety disorder, they found the volume of the amygdala of these children was significantly larger. In another study in children with generalized anxiety disorder, researchers noted the opposite. These kids showed a decrease in amygdala volume, particularly on the left-hand side.
What about the MRI of adults with generalized anxiety disorder? In one European study, researchers discovered that women with generalized anxiety disorder had both larger amygdala volumes and a greater volume in a portion of the brain called the pre-frontal cortex. Both of these brain regions are involved in processing emotions - including fear and anxiety.
The MRI of a Person with Generalized Anxiety Disorder
Although not everyone with generalized anxiety disorder will have the same MRI findings, people who have this disorder are most likely to show changes in areas of the brain, such as the amygdala, that process emotions. Researchers also believe that some of the pathways the amygdala uses to communicate with other areas of the brain are altered in people with generalized anxiety disorder.
The amygdala plays another important role. It deems which emotional memories stored in the cortex of the brain are important. When a person experiences fear in a particular situation, the memory of that frightening situation is stored in the brain, but not before it’s “marked” by the amygdala as being high-priority. When a similar anxiety-provoking event is experienced again, the nerve cells are primed to act more quickly and dramatically. This may explain why people with generalized anxiety disorder overreact to certain stimuli.
The MRI of People with Generalized Anxiety Disorder: The Bottom Line?
People with generalized anxiety disorder show changes in areas of the brain that process and filter emotions such as the amygdala. Some scientists have speculated that the amygdala can be retrained not to react to non-threatening emotional stimuli, offering some relief for people with this disorder. Hopefully further research will shed more light on this issue.
References
Biological Psychiatry.Volume 48, Issue 1, Pages 51-57 (1 July 2000)
Biological Psychiatry.Volume 57, Issue 9, Pages 961-966 (1 May 2005)
EUROPEAN ARCHIVES OF PSYCHIATRY AND CLINICAL NEUROSCIENCE. DOI: 10.1007/s00406-010-0147-5
