The default mode network (DMN) was revealed by O-15 gas PET as a brain network activated at rest. ¹⁾
Resting-state functional MRI (rs-fMRI) is used to evaluate the network in the brain, but in principle, evaluation by BOLD (blood oxygenation level-dependent) signals cannot separate the effects of cerebral oxygen metabolism and cerebral blood flow. ²⁾
We evaluated the functional correlation in DMN by O-15 gas PET, and the correlation (Intersubject correlation coefficients) between cerebral blood flow (CBF) and cerebral oxygen consumption (CMRO2) was evaluated. ³⁾
As a result, it was found that CBF showed more functional correlation than CMRO2, and that changes in blood flow could capture the functional correlation in DMN more accurately compared to oxygen metabolism. ³⁾

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