Magnetic resonance imaging of active, passive and imaginary movement

Objective To assess any differences in brain activation during active, passive and imaginary movement of the hands using blood oxygen level-dependent functional magnetic resonance imaging (fMRI), and to provide references for the cortical reorganization in patients with brain injuries. Methods Twenty healthy, right-handed, adult volunteers were studied. fMRI was performed during active, passive and imaginary fist clutching. Whole brain analysis and group analysis were applied to get the voxels, the volume of activation, the peak t-score and its coordinates. Results Active and passive movement both produced significant activation in the contralateral sensorimotor cortex, the contralateral supplementary motor area and the ipsilateral cerebellum. The sensorimotor cortex was the most frequently and most strongly activated brain area. Imaginary movement produced significant bilateral activation in the supplementary motor area. Conclusions Active and passive movement induce similar brain activation patterns. This indicates that passive might replace active movement when observing activation of the brain's cortex during the rehabilitation of patients with hemiplegia. Key words: Functional magnetic resonance imaging; Active movement; Passive movement; Imaginary movement; Supplementary motor area; Brain imaging; Hands