Superior temporal gyrus volumes in pediatric generalized anxiety disorder.
BACKGROUND
The essential symptoms of generalized anxiety disorder (GAD) are intrusive worry about everyday life circumstances and social competence, and associated autonomic hyperarousal. The amygdala, a brain region involved in fear and fear-related behaviors in animals, and its projections to the superior temporal gyrus (STG), thalamus, and to the prefrontal cortex are thought to comprise the neural basis of our abilities to interpret social behaviors. Larger amygdala volumes were previously reported in pediatric GAD; however, the brain regions involved in social intelligence were not examined in this pilot study.


METHODS
Magnetic resonance imaging (MRI) was used to measure the STG, thalamus, and prefrontal volumes in 13 medically healthy child and adolescent subjects with generalized anxiety disorder (GAD) and 98 comparison subjects, who were at low familial risk for mood and psychotic disorders. Groups were similar in age, gender, height, weight, handedness, socioeconomic status, and full-scale IQ.


RESULTS
The total, white matter, and gray matter STG volumes were significantly larger in GAD subjects compared with control subjects. Thalamus and prefrontal lobe volumes did not differ between groups. Findings of significant side-by-diagnosis interactions for STG and STG white matter volumes suggest that there is a more pronounced right > left asymmetry in total and STG white matter volumes in pediatric GAD subjects compared with control subjects. A significant correlation between the STG white matter percent asymmetry index with the child report of the Screen for Child Anxiety Related Emotional Disorders Scale was seen.


CONCLUSIONS
These data agree with previous work implicating posterior right-hemispheric regions in anxiety disorders and may suggest developmental alterations in pediatric GAD.
De Bellis
Michael D
MD
University of Pittsburgh Medical Center, Developmental Traumatology Program (Developmental Family Health Clinic and Neuroimaging Laboratory), Western Psychiatric Institute and Clinic, Rm 392, 3811 O'Hara Street, Pittsburgh, PA 15213, USA.
Keshavan
Matcheri S
MS
Shifflett
Heather
H
Iyengar
Satish
S
Dahl
Ronald E
RE
Axelson
David A
DA
Birmaher
Boris
B
Hall
Julie
J
Moritz
Grace
G
Ryan
Neal D
ND
D000293:Adolescent; D000679:Amygdala / Q000473:pathology; D001008:Anxiety Disorders / Q000175:diagnosis* / Q000523:psychology; D002648:Child; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000473:pathology; D017397:Prefrontal Cortex / Q000473:pathology; D012016:Reference Values; D013702:Temporal Lobe / Q000473:pathology*; D013788:Thalamus / Q000473:pathology