Amygdaloid regional cerebral blood flow and subjective fear during symptom provocation in anxiety disorders.

Whether the amygdala is involved predominantly in emotional perception or in the generation of emotional states has been debated. We reviewed and reanalyzed data from our laboratory, indicating that subjective feelings of fear and distress are correlated with regional cerebral blood flow (rCBF) in the right but not the left amygdala during anxiety provocation in individuals with social anxiety disorder, specific phobias. and posttraumatic stress disorder. Positron emission tomography is a correlative technique, and casual inferences cannot be drawn. However, because studies demonstrate that treatment of social anxiety disorder with cognitive behavior therapy and selective serotonin reuptake inhibitors results in reduced rCBF in the amygdaloid complex and prospective studies reveal that treatment-induced alterations in amygdala rCBF can predict 1 year follow-up status in social anxiety disorder data support the notion that the amygdala, at least in part, seem casually involved in generating the subjective experience of fear.