Regional Differences in the Coupling between Resting Cerebral Blood Flow and Metabolism may Indicate Action Preparedness as a Default State.

@article{citeulike:2876977, abstract = {Although most functional neuroimaging studies examine task effects, interest intensifies in the "default" resting brain. Resting conditions show consistent regional activity, yet oxygen extraction fraction constancy across regions. We compared resting cerebral metabolic rates of glucose (CMRgl) measured with (18)F-labeled 2-fluoro-2-deoxy-D-glucose to cerebral blood flow (CBF) (15)O-H(2)O measures, using the same positron emission tomography scanner in 2 samples (n = 60 and 30) of healthy right-handed adults. Region to whole-brain ratios were calculated for 35 standard regions of interest, and compared between CBF and CMRgl to determine perfusion relative to metabolism. Primary visual and auditory areas showed coupling between CBF and CMRgl, limbic and subcortical regions-basal ganglia, thalamus and posterior fossa structures-were hyperperfused, whereas association cortices were hypoperfused. Hyperperfusion was higher in left than right hemisphere for most cortical and subcallosal limbic regions, but symmetric in cingulate, basal ganglia and somatomotor regions. Hyperperfused regions are perhaps those where activation is anticipated at short notice, whereas downstream cortical modulatory regions have longer "lead times" for deployment. The novel observation of systematic uncoupling of CBF and CMRgl may help elucidate the potential biological significance of the "default" resting state. Whether greater left hemispheric hyperperfusion reflects lateral dominance needs further examination.}, address = {Section of Neuropsychiatry, Department of Psychiatry and the Philadelphia Veterans Administration Medical Center Philadelphia, PA 19104, USA.}, author = {Gur, Ruben C C. and Ragland, J Daniel D. and Reivich, Martin and Greenberg, Joel H H. and Alavi, Abass and Gur, Raquel E E. }, citeulike-article-id = {2876977}, issn = {1460-2199}, journal = {Cerebral cortex (New York, N.Y. : 1991)}, keywords = {baseline, kristina, neuromodulation}, month = {June}, posted-at = {2008-06-09 14:51:21}, priority = {2}, title = {Regional Differences in the Coupling between Resting Cerebral Blood Flow and Metabolism may Indicate Action Preparedness as a Default State.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/18534991}, year = {2008} }

TY - JOUR ID - citeulike:2876977 L3 - citeulike-article-id:2876977 TI - Regional Differences in the Coupling between Resting Cerebral Blood Flow and Metabolism may Indicate Action Preparedness as a Default State. JF - Cerebral cortex (New York, N.Y. : 1991) AD - Section of Neuropsychiatry, Department of Psychiatry and the Philadelphia Veterans Administration Medical Center Philadelphia, PA 19104, USA. SN - 1460-2199 N2 - Although most functional neuroimaging studies examine task effects, interest intensifies in the "default" resting brain. Resting conditions show consistent regional activity, yet oxygen extraction fraction constancy across regions. We compared resting cerebral metabolic rates of glucose (CMRgl) measured with (18)F-labeled 2-fluoro-2-deoxy-D-glucose to cerebral blood flow (CBF) (15)O-H(2)O measures, using the same positron emission tomography scanner in 2 samples (n = 60 and 30) of healthy right-handed adults. Region to whole-brain ratios were calculated for 35 standard regions of interest, and compared between CBF and CMRgl to determine perfusion relative to metabolism. Primary visual and auditory areas showed coupling between CBF and CMRgl, limbic and subcortical regions-basal ganglia, thalamus and posterior fossa structures-were hyperperfused, whereas association cortices were hypoperfused. Hyperperfusion was higher in left than right hemisphere for most cortical and subcallosal limbic regions, but symmetric in cingulate, basal ganglia and somatomotor regions. Hyperperfused regions are perhaps those where activation is anticipated at short notice, whereas downstream cortical modulatory regions have longer "lead times" for deployment. The novel observation of systematic uncoupling of CBF and CMRgl may help elucidate the potential biological significance of the "default" resting state. Whether greater left hemispheric hyperperfusion reflects lateral dominance needs further examination. KW - baseline KW - kristina KW - neuromodulation AU - Gur, Ruben C AU - Ragland, J Daniel AU - Reivich, Martin AU - Greenberg, Joel H AU - Alavi, Abass AU - Gur, Raquel E PY - 2008/06/04/ UR - http://view.ncbi.nlm.nih.gov/pubmed/18534991 ER -