Cortical Layer-Dependent BOLD and Arterial Blood Volume Responses Measured by MT-Varied BOLD FMRI

Tae Kim¹, Seong-Gi Kim^1,2

The cortical depth profile of CBVa was measured to examine spatial specificity in a cortical layer model. BOLD and CBVa change during visual stimulation was simultaneously measured by MT-varied BOLD fMRI in cats. The highest signal changes were detected at cortical surface areas in conventional BOLD fMRI, but at the middle of cortex and the cortical surface in CBVa fMRI. This suggests that both parenchymal and upstream pial arterial vessels dilate, and the CBVa can be used to improve spatial specificity of fMRI signals within the cortex.