Abstract #0769

Comparative Oxidative Demands in Cortex & Subcortex Revealed By High Field Calibrated fMRI

Basavaraju G. Sanganahalli^1,2, Peter Herman^1,2, Douglas L. Rothman^2,3, Hal Blumenfeld^2,4, Fahmeed Hyder^2,3

¹Diagnostic Radiology, Yale University, New Haven, CT, USA; ²Quantitative Neuroscience with Magnetic Resonance in Medicine (QNMR), Yale University, New Haven, CT, USA; ³Diagnostic Radiology & Biomedical Engineering, Yale University, New Haven, CT, USA; ⁴Neurology, Neurosurgery, Neuroscience, Yale University, New Haven, CT, USA

Because oxidative demands in cortex and subcortex are largely unknown, we evaluated regional energetics with high field calibrated fMRI in rat brain. During somatosensory stimulation we measured BOLD, CBV, and CBF to calculate δCMR_O2 in cortex and subcortex and compared these with neural recordings. We find that while neural-BOLD, neural-CBV, and neural-CBF relationships differ significantly between cortex and subcortex, δCMR_O2 values are quite similar in these regions. These regional energetic estimates from calibrated fMRI are in agreement with neural recordings. Thus these results suggest that neurometabolic couplings are similar in cortex and subcortex, but neurovascular couplings are quite different.