Yuji Shen1, Ida Mengyi Pu2, Risto A. Kauppinen3, Xavier Golay4
1School of Medicine, University of Birmingham, Birmingham, UK; 2Department of Computing, Goldsmiths, University of London, London, UK; 3Biomedical NMR Research Center, Dartmouth Medical School, Hanover, NH 03755, USA; 4Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, London, UK
We examined spatial overlap and T1 values of the activated voxels revealed by grey matter nulled (GMN) and vascular space occupancy (VASO) fMRI techniques in the human visual cortex at 3T. Both fMRI techniques are designed to reveal blood volume changes during brain activation. It was found that the activated voxels by GMN and VASO fMRI methods overlap only by ~10%. Baseline T1 values in activated voxels were 1608 283 ms and 1247 214 ms for GMN and VASO fMRI, respectively, suggesting that these fMRI techniques probe different parenchymal compartments.