A magnetic resonance imaging study of cortical thickness in animal phobia.
BACKGROUND
Despite the high prevalence of specific phobia (SP), its neural substrates remain undetermined. Although an initial series of functional neuroimaging studies have implicated paralimbic and sensory cortical regions in the pathophysiology of SP, to date contemporary morphometric neuroimaging methods have not been applied to test specific hypotheses regarding structural abnormalities.


METHODS
Morphometric magnetic resonance imaging (MRI) methods were used to measure regional cortical thickness in 10 subjects with SP (animal type) and 20 healthy comparison (HC) subjects.


RESULTS
Consistent with a priori hypotheses, between-group differences in cortical thickness were found within paralimbic and sensory cortical regions. Specifically, in comparison with the HC group, the SP group exhibited increased cortical thickness in bilateral insular, bilateral pregenual anterior cingulate, and bilateral posterior cingulate cortex as well as left visual cortical regions.


CONCLUSIONS
Taken together, these structural findings parallel results from initial functional imaging studies that implicate paralimbic and sensory cortical regions in the mediating anatomy of SP symptoms. Further research will be necessary to replicate these findings and to determine their specificity as well as their pathophysiologic significance.
Rauch
Scott L
SL
Department of Psychiatry, Massachusetts General Hospital-East, 2nd Floor, Building 149, 13th Street, Charlestown, MA 02129, USA.
Wright
Christopher I
CI
Martis
Brian
B
Busa
Evelina
E
McMullin
Katherine G
KG
Shin
Lisa M
LM
Dale
Anders M
AM
Fischl
Bruce
B
D000328:Adult; D000818:Animals; D002540:Cerebral Cortex / Q000033:anatomy & histology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006179:Gyrus Cinguli / Q000033:anatomy & histology; D006801:Humans; D008032:Limbic System / Q000033:anatomy & histology; D008279:Magnetic Resonance Imaging; D008297:Male; D010698:Phobic Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D015995:Prevalence; D013003:Somatosensory Cortex / Q000033:anatomy & histology*