A functional magnetic resonance imaging study of cortical regions associated with motor task execution and motor ideation in humans

Although motor performance may be enhanced through mental practice, the neurophysiological substrate of mental stimulation (ideation) of a motor task is not well established. We used blood oxygen level-dependent contrast echo planar imaging at 1.5 T to identify regions of increased neural activity during the performance and ideation of a motor task. Five subjects performed a sequential finger-to-thumb opposition task and also imagined themselves performing the task in the absence of actual muscle movement. In all subjects, the left primary sensorimotor cortex showed more activation with actual movement than with motor ideation, but two subjects had significant activation with motor ideation. The left premotor area showed comparable activation with both actual and imagined performance in three subjects. These findings support the involvement of the primary motor area as well as the premotor area in motor ideation. (C) 1995 Wiley-Liss, Inc*