The effect of global cerebral vasodilation on focal activation hemodynamics Export

@article{citeulike:611208, abstract = {In view of the potential of global resting blood flow level to confound the interpretation of blood oxygenation level-dependent (BOLD) fMRI studies, we investigated the effect of pronounced elevation in baseline cerebral blood flow (CBF) on BOLD and CBF responses to functional activation. Twelve healthy volunteers performed bilateral finger apposition while attending to a radial yellow/blue checkerboard. Three levels of global CBF increase were achieved by inhaling 5, 7.5 or 10\% CO2. CBF and BOLD signals were simultaneously quantified using interleaved multi-slice pulsed arterial spin labeling (PASL) and T2*-weighted gradient echo sequences. Increasing basal CBF produced a significant decrease in the activation-induced BOLD response, with the slope of the optimal linear fit of activation versus basal BOLD signal changes of - 0.32 [plus-or-minus sign] 0.01\%/\% for motor and visual cortex regions of interest (ROIs). While the modulation in basal flow level also produced a statistically significant effect on the activation-induced CBF change, the degree of relative attenuation of the flow response was slight, with a slope of - 0.18 [plus-or-minus sign] 0.02\%/\% in the motor and - 0.13 [plus-or-minus sign] 0.01\%/\% in the visual cortex ROI. The current findings describe a strong attenuation of the BOLD response at significantly elevated basal flow levels and call for independent quantification of resting CBF in BOLD fMRI studies that involve subjects and/or conditions with markedly elevated global perfusion.}, author = {Stefanovic, Bojana and Warnking, Jan M. and Rylander, Karin M. and Pike, Bruce G.}, citeulike-article-id = {611208}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.neuroimage.2005.10.038}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/16337135}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=16337135}, citeulike-linkout-3 = {http://www.sciencedirect.com/science/article/B6WNP-4HR76JV-1/2/986e0fe4df30f44897173e2aec89fd4d}, day = {15}, doi = {10.1016/j.neuroimage.2005.10.038}, journal = {NeuroImage}, keywords = {bold, co2}, month = {April}, number = {3}, pages = {726--734}, posted-at = {2007-02-08 21:36:11}, priority = {2}, title = {The effect of global cerebral vasodilation on focal activation hemodynamics}, url = {http://dx.doi.org/10.1016/j.neuroimage.2005.10.038}, volume = {30}, year = {2006} }

TY - JOUR ID - citeulike:611208 L3 - citeulike-article-id:611208 N2 - In view of the potential of global resting blood flow level to confound the interpretation of blood oxygenation level-dependent (BOLD) fMRI studies, we investigated the effect of pronounced elevation in baseline cerebral blood flow (CBF) on BOLD and CBF responses to functional activation. Twelve healthy volunteers performed bilateral finger apposition while attending to a radial yellow/blue checkerboard. Three levels of global CBF increase were achieved by inhaling 5, 7.5 or 10% CO2. CBF and BOLD signals were simultaneously quantified using interleaved multi-slice pulsed arterial spin labeling (PASL) and T2*-weighted gradient echo sequences. Increasing basal CBF produced a significant decrease in the activation-induced BOLD response, with the slope of the optimal linear fit of activation versus basal BOLD signal changes of - 0.32 [plus-or-minus sign] 0.01%/% for motor and visual cortex regions of interest (ROIs). While the modulation in basal flow level also produced a statistically significant effect on the activation-induced CBF change, the degree of relative attenuation of the flow response was slight, with a slope of - 0.18 [plus-or-minus sign] 0.02%/% in the motor and - 0.13 [plus-or-minus sign] 0.01%/% in the visual cortex ROI. The current findings describe a strong attenuation of the BOLD response at significantly elevated basal flow levels and call for independent quantification of resting CBF in BOLD fMRI studies that involve subjects and/or conditions with markedly elevated global perfusion. IS - 3 JF - NeuroImage EP - 734 TI - The effect of global cerebral vasodilation on focal activation hemodynamics VL - 30 SP - 726 KW - bold KW - co2 AU - Stefanovic, Bojana AU - Warnking, Jan AU - Rylander, Karin AU - Pike, Bruce PY - 2006/04/15/ UR - http://dx.doi.org/10.1016/j.neuroimage.2005.10.038 ER -