Perfusion-based FMRI in Human LGN and Visual Cortex Reveals a Regional Difference in the Coupling Between Cerebral Blood Flow and BOLD
Lu K, Zangwill L, Liu T, Perthen J, Duncan R
University of California San Diego
It has been observed that the percentage change of BOLD signal in lateral geniculate nucleus (LGN) due to activation is typically 2-3 times smaller than that in primary visual cortex (V1). We investigated the origin of this difference using perfusion-based functional MRI. Our results suggest that the BOLD difference in LGN and V1 may reflect a regional dependence of the coupling between cerebral blood flow (CBF) and CMRO2. Additional experiments are required to test this hypothesis.