Abstract #0538

Woolrich M, Chiarelli P, Gallichan D, Liu T

Functional MRI techniques such as Arterial Spin Labelling (ASL), Vascular Space Occupancy (VASO) and Blood Oxyenation Level Dependent (BOLD) have been developed to investigate the different haemodynamic changes of cerebral blood flow (CBF), cerebral blood volume (CBV), and blood oxygenation respectively. We propose an approach which infers these three haemodynamic changes simultaneously via a physiological model of ASL data acquired at multiple echo times. The physiological model describes the contributions of the changes in CBF, CBV and BOLD to the measured data. This can be achieved with a fairly simple model of the physiology. The method infers physiologically plausible haemodynamic changes in response to a visual task. We also demonstrate increased sensitivity in inferring CBF when compared to standard approaches of extracting it from tag-control differencing of ASL data. This approach means that a range of complementary information can be efficiently and simultaneously gathered in functional brain studie