Does baseline cerebral blood flow affect task-related blood oxygenation level dependent response in schizophrenia?
BACKGROUND
Experimental changes in resting cerebral blood flow (CBF) affect task-related blood oxygenation level dependent (BOLD) responses. Since patients with schizophrenia have been shown to have abnormal resting CBF, we sought to determine whether differences between patients and healthy controls in resting CBF contribute to group differences in BOLD response.


METHODS
BOLD images were acquired in nineteen patients and twenty healthy controls looking at photographs of faces, and resting CBF was measured by arterial spinning labeling. Resting CBF was then used to adjust group differences in task-related BOLD signal increases in linear models.


RESULTS
Patients had different resting CBF from healthy controls in right basal ganglion and bilateral thalami. Associations between resting CBF and delta BOLD were evident in bilateral prefrontal areas, visual processing areas and right fusiform gyrus. Other areas showed significant three-way interactions among group, delta BOLD and resting CBF. Incorporating resting CBF when modeling group differences in BOLD responses identified areas of group differences in task-related delta BOLD response that were not evident in simple group contrasts. These were in right inferior frontal cortex, left insula, left middle frontal cortex and bilateral frontal poles.


CONCLUSIONS
Adjusting for inter-group differences in resting CBF altered inter-group differences in task-related BOLD response in some areas, suggesting that assessing resting CBF in task-related BOLD studies could increase sensitivity and validity. In multiple regions, the relationship between resting CBF and task-related signal increases in BOLD differed between patients and controls, providing new evidence of possible metabolic and/or vascular pathology.
Department of Psychiatry, Yale University, Connecticut Mental Health Center, New Haven, CT 06519, USA.
Jiacheng
J
Liu
Maolin
M
Qiu
R Todd
RT
Constable
Bruce E
BE
Wexler
D000328:Adult; D000704:Analysis of Variance; D001158:Arteries; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004644:Emotions; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D012146:Rest; D012559:Schizophrenia / Q000473:pathology* / Q000503:physiopathology*; D013113:Spin Labels
D013113:Spin Labels; D010100:Oxygen