1NMR-Unit, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; 2Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Tbingen, Germany; 3Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; 4Cognitive and Clinical Neuroscience, Maastricht University, Maastricht, Netherlands
Based on recent studies in monkeys (Goense, J, et al., Neuron, in press), the changes in cerebral blood volume (CBV) were investigated in human brain regions that show negative BOLD responses during a visual task. Therefore a CBV-sensitive VASO method was implemented that can account for BOLD and inflow contaminations at 7T. In regions with negative BOLD responses, significant CBV decreases can be seen. This CBV decrease is dominated by voxels that include the cortical surface at the transition region between grey matter and cerebrospinal fluid, while many voxels in deeper layers show a CBV increase.