Spatially dissociated flow-metabolism coupling in brain activation.
The relationships among cerebral blood flow (CBF), oxygen consumption (CMRO(2)) and glucose use (CMR(glc)) constitute the basis of functional brain-imaging. Here we report spatially dissociated changes of CMRO(2) and CBF during motor activity that lead us to propose a revision of conventional CBF-CMRO(2) coupling models. In the left primary and supplementary motor cortices, CBF and CMRO(2) rose significantly during finger-thumb tapping. However, in the right putamen CBF did not rise, despite a significant increase in CMRO(2). We explain these observations by invoking a central command mechanism that regulates CBF in the putamen in anticipation of movement. By this mechanism, CBF rose in the putamen before the measurements of CBF and CMRO(2) while CMRO(2) rose when actual motion commenced.
Vafaee
Manouchehr S
MS
Center of Functionally Integrative Neuroscience, University of Aarhus, and PET Center, Aarhus University Hospitals, Aarhus, Denmark. manou@pet.auh.dk
Gjedde
Albert
A
D000328:Adult; D001931:Brain Mapping; D002531:Cerebellum / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D004292:Dominance, Cerebral / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D005385:Fingers / Q000294:innervation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000098:blood supply* / Q000000981:diagnostic imaging*; D010101:Oxygen Consumption / Q000502:physiology*; D011699:Putamen / Q000000981:diagnostic imaging / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology; D014055:Tomography, Emission-Computed