Functional and structural connectivity between the perigenual anterior cingulate and amygdala in bipolar disorder.
OBJECTIVE
Abnormalities in the morphology and function of two gray matter structures central to emotional processing, the perigenual anterior cingulate cortex (pACC) and amygdala, have consistently been reported in bipolar disorder (BD). Evidence implicates abnormalities in their connectivity in BD. This study investigates the potential disruptions in pACC-amygdala functional connectivity and associated abnormalities in white matter that provides structural connections between the two brain regions in BD.


METHODS
Thirty-three individuals with BD and 31 healthy comparison subjects (HC) participated in a scanning session during which functional magnetic resonance imaging (fMRI) during processing of face stimuli and diffusion tensor imaging (DTI) were performed. The strength of pACC-amygdala functional connections was compared between BD and HC groups, and associations between these functional connectivity measures from the fMRI scans and regional fractional anisotropy (FA) from the DTI scans were assessed.


RESULTS
Functional connectivity was decreased between the pACC and amygdala in the BD group compared with HC group, during the processing of fearful and happy faces (p < .005). Moreover, a significant positive association between pACC-amygdala functional coupling and FA in ventrofrontal white matter, including the region of the uncinate fasciculus, was identified (p < .005).


CONCLUSIONS
This study provides evidence for abnormalities in pACC-amygdala functional connectivity during emotional processing in BD. The significant association between pACC-amygdala functional connectivity and the structural integrity of white matter that contains pACC-amygdala connections suggest that disruptions in white matter connectivity may contribute to disturbances in the coordinated responses of the pACC and amygdala during emotional processing in BD.
Wang
Fei
F
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychiatry, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut. Electronic address: fei.wang@yale.edu.
Kalmar
Jessica H
JH
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychiatry, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut.
He
Yong
Y
State Key Laboratory of Cognitive Neuroscience, Beijing Normal University, Beijing, China; McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.
Jackowski
Marcel
M
Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut; Institute of Mathematics and Statistics, University of São Paulo, São Paulo, Brazil.
Chepenik
Lara G
LG
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychiatry, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut.
Edmiston
Elliot Kale
EK
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut.
Tie
Karen
K
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychiatry, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut.
Gong
Gaolang
G
Biomedical Engineering Department, University of Alberta, Edmonton, Alberta, Canada.
Shah
Maulik P
MP
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychiatry, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut.
Jones
Monique
M
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut.
Uderman
Jodi
J
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut.
Constable
R Todd
RT
Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut.
Blumberg
Hilary P
HP
Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut; Department of Psychiatry, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut.
D000328:Adult; D000679:Amygdala / Q000473:pathology* / Q000503:physiopathology*; D001714:Bipolar Disorder / Q000473:pathology* / Q000503:physiopathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005149:Facial Expression; D005260:Female; D006179:Gyrus Cinguli / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000473:pathology* / Q000503:physiopathology*; D013702:Temporal Lobe / Q000503:physiopathology