It has repeatedly been reported that the processing of neutral (e.g. [49]), negative (e.g. [50]), or angry faces (e.g. [51]) in social phobia requires an increased neuronal activity within the amygdala. However, just recently it could be shown that the increased amygdala activity seems rather to be related to the processing of angry than of fearful faces, and does not differentiate between generalized anxiety and social phobia [22]. In contrast, patients with social phobia but without generalized anxiety recruit more neuronal resources during the processing of fearful faces, especially in frontal brain regions (middle frontal gyrus/frontal polar cortex, BA 10; lateral frontal cortex, BA 46). The CSD maps of the present study indicate that socially anxious individuals engage similar brain circuits during the processing of chemosensory anxiety signals. However, in the present study, the degree of general anxiety was not obtained and therefore, could be confounded with social anxiety. Instead, as socially anxious and non-anxious participants scored low in depression and medium in social interest, it was excluded that the present effect of social anxiety is biased by the degree of depression or social interest.
