Brain function can be mapped with magnetic resonance (MR) imaging sensitized to regional changes in blood oxygenation due to cortical activation. Several MR imaging methods, including conventional imaging and echo-planar imaging, have been successfully used for this purpose. The authors investigated spiral k-space MR imaging, implemented with an unmodified 1.5-T clinical imager, for imaging of cortical activation. A gradient-echo, spiral k-space imaging method was used to measure activation in the primary visual cortex (number sequence task), primary motor cortex (fist-clenching task), and prefrontal cortex (verbal fluency task). Comparison of conventional and spiral k-space imaging in the visual and motor cortex, in which signal-to-noise ratio, voxel size, and imaging time were matched, showed that artifacts were reduced with the spiral k-space method, while the area and degree of activation were similar. The number of sections that could be imaged in a fixed time interval was increased by a factor of four with this implementation of spiral k-space imaging compared with conventional imaging.