Alan J. Stone1, Kevin Murphy2, Ashley D. Harris2, Richard G. Wise2
1Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University , Cardiff, United Kingdom; 2Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, United Kingdom
We present a refined method for hyperoxic and hypercapnic calibration of BOLD signal that yields measurements of the absolute rate of cerebral oxygen consumption (CMRO2). We demonstrate that the measurements can be obtained in 9 mins, are repeatable within a scan session and are sensitive to sustained (18 min) task-related increases in absolute CMRO2. The sensitivity to sustained changes in CMRO2 indicates that the method proposed is promising for clinical or pharmacological applications in which CMRO2 is altered.