In the brain, brief neural activity creates changes in local blood flow (CBF) and oxygen uptake (CMRO2). Functional magnetic resonance imaging (fMRI) can measure these changes as a blood oxygenation level dependent (BOLD) signal. The BOLD response to brief stimulations is often termed the hemodynamic response function (HRF). We recently proposed the Arterial Impulse model for the HRF based on a combination of underdamped CBF and CMRO2 responses. Here, we used arterial spin-labeling (ASL) to measure both the BOLD HRF and CBF, and then used our model to obtain estimates of the CMRO2 time course.