Quantitation of regional cerebral blood flow increases during motor activation: A steady-state arterial spin tagging study

Steady-state arterial spin tagging MRI approaches were used to quantitate regional cerebral blood flow increases during finger tapping tasks in seven normal subjects. Statistically significant increases in cerebral blood flow were observed in the contralateral primary sensorimotor cortex in all seven subjects and in the supplementary motor area in five subjects. The intrinsic spatial resolution of the cerebral blood flow images was ~4 mm. If no spatial filtering was applied, the average increase in cerebral blood flow in the activated primary sensorimotor cortex was 60 ± 10 cc/100 g/min (91 ± 32%). If the images were filtered to a spatial resolution of 15 mm, the average increase in cerebral blood flow in the activated primary sensorimoter cortex was 23 ± 7 cc/100 g/min (42 ± 15%), in agreement with previously reported ¹³³Xe and PET results.