Causes
The causes of GAD are not yet well understood. Traumatic life experiences, faulty conditioning, genetic influences, and neuro biological dysfunction are considered to be potential etiological factors for GAD and other anxiety disorders (8). GAD tends to cluster in families. Twin studies have shown a moderate hereditary influence , which is, however, less intense than in other anxiety disorders, e.g., panic disorder. The neurobiological factors under discussion include disturbances of various neurotransmitter systems (serotonin, epinephrine nor epinephrine, GABA) (11–13). Structural and functional neuroimaging of GAD patients has revealed abnormalities in the amygdala, the dorsomedial prefrontal cortex, and other brain areas (e3–e6).