Dynamic changes in the cerebral metabolic rate of oxygen (CMRO2) and oxygen extraction ratio (OER) in an event-related functional MRI (ER-fMRI) were measured in this study. Six subjects participated in this study at a magnetic field of 1.9 T. Cerebral blood flow (CBF) and blood oxygenation level-dependent (BOLD) changes were acquired during the brief visual stimulation, and the corresponding changes in CMRO2 and OER were then determined. The results showed that the maximum relative changes in CMRO2 and OER were about 10.36 ± 0.85 and -6.54 ± 0.55%, respectively, while the maximum changes in CBF and BOLD were approximately 17.35 ± 1.37 and 1.03 ± 0.06%, respectively. The CBF, CMRO2, and OER changes reach their maximum approximately 1 s earlier than the BOLD signal change (4.15 ± 0.21, 4.16 ± 0.21, and 4.17 ± 0.21 s vs 5.12 ± 0.24 s after stimulation, P < 0.05).
- Blood oxygenation level-dependent
- Cerebral blood flow
- Cerebral metabolic rate of oxygen
- Magnetic resonance imaging
- Oxygen extraction ratio
ASJC Scopus subject areas
- Cognitive Neuroscience