Resting brain perfusion in social anxiety disorder: a voxel-wise whole brain comparison with healthy control subjects.
BACKGROUND
Social anxiety disorder (SAD) is a condition characterised by fears of social interaction and performance situations. SAD may be related to a dysregulation or hyperactivity of cortico-limbic circuitry. This is the first voxel-based whole brain study comparing resting function in SAD to a normal control group.


METHODS
Resting perfusion in adult subjects with generalised SAD was compared with healthy adult volunteers using Statistical Parametric Mapping (SPM). In subjects with SAD, correlations were also sought between resting perfusion and clinical severity measured using the total Liebowitz Social Anxiety Scale (LSAS).


RESULTS
Twenty-eight subjects with SAD were compared with 19 healthy volunteers. SAD subjects had increased resting perfusion in the frontal cortex and right cerebellum, and decreased perfusion in the pons, left cerebellum, and right precuneus. Total LSAS correlated positively with left frontal cortex resting perfusion, and negatively with right fusiform and right lingual perfusion.


CONCLUSIONS
This study demonstrated increased resting frontal function in social anxiety disorder that is consistent with its hypothesised role in the modulation of excessive limbic activity in anxiety disorders. The correlation of posterior cortical resting function with the severity of SAD symptoms may point to defective perception of self and others.
Warwick
J M
JM
MRC Unit for Stress and Anxiety Disorders, Faculty of Health Sciences, Stellenbosch University, Cape Town, South Africa. jw@sun.ac.za
Carey
P
P
Jordaan
G P
GP
Dupont
P
P
Stein
D J
DJ
D000328:Adult; D000379:Agoraphobia / Q000000981:diagnostic imaging / Q000473:pathology*; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging; D001931:Brain Mapping; D005260:Female; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods