Abnormal functional connectivity of the medial cortex in euthymic bipolar II disorder.
This project utilized functional MRI (fMRI) and a motor activation paradigm to investigate neural circuitry in euthymic bipolar II disorder. We hypothesized that circuitry involving the cortical midline structures (CMS) would demonstrate abnormal functional connectivity. Nineteen subjects with recurrent bipolar disorder and 18 controls were studied using fMRI and a motor activation paradigm. We used functional connectivity analyses to identify circuits with aberrant connectivity. We found increased functional connectivity among bipolar subjects compared to healthy controls in two CMS circuits. One circuit included the medial aspect of the left superior frontal gyrus and the dorsolateral region of the left superior frontal gyrus. The other included the medial aspect of the right superior frontal gyrus, the dorsolateral region of the left superior frontal gyrus and the right medial frontal gyrus and surrounding region. Our results indicate that CMS circuit dysfunction persists in the euthymic state and thus may represent trait pathology. Future studies should address whether these circuits contribute to relapse of illness. Our results also suggest the possibility that aberrations of superior frontal circuitry may impact default mode network and cognitive processes.
George E. Wahlen Veterans Affairs Medical Center, 500 Foothill Drive, Salt Lake City, UT 84148, USA; University of Utah, 201 Presidents Circle, Salt Lake City, UT 84112, USA. Electronic address: wmarchand@me.com.
William R
WR
Marchand
George E. Wahlen Veterans Affairs Medical Center, 500 Foothill Drive, Salt Lake City, UT 84148, USA; University of Utah, 201 Presidents Circle, Salt Lake City, UT 84112, USA.
James N
JN
Lee
George E. Wahlen Veterans Affairs Medical Center, 500 Foothill Drive, Salt Lake City, UT 84148, USA.
Susanna
S
Johnson
George E. Wahlen Veterans Affairs Medical Center, 500 Foothill Drive, Salt Lake City, UT 84148, USA; University of Utah, 201 Presidents Circle, Salt Lake City, UT 84112, USA.
Phillip
P
Gale
George E. Wahlen Veterans Affairs Medical Center, 500 Foothill Drive, Salt Lake City, UT 84148, USA; University of Utah, 201 Presidents Circle, Salt Lake City, UT 84112, USA.
John
J
Thatcher
D000328:Adult; D001714:Bipolar Disorder / Q000473:pathology*; D002540:Cerebral Cortex / Q000098:blood supply / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009434:Neural Pathways / Q000098:blood supply / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D055815:Young Adult
D010100:Oxygen
Bipolar disorder; Functional MRI; Medial cortex