Mesial Motor Areas in Self-Initiated Versus Externally Triggered Movements Examined With fMRI: Effect of Movement Type and Rate
- 1 June 1999
- journal article
- clinical trial
- Published by American Physiological Society in Journal of Neurophysiology
- Vol. 81 (6), 3065-3077
- https://doi.org/10.1152/jn.1999.81.6.3065
Abstract
Mesial motor areas in self-initiated versus externally triggered movements examined with fMRI: effect of movement type and rate. The human frontomesial cortex reportedly contains at least four cortical areas that are involved in motor control: the anterior supplementary motor area (pre-SMA), the posterior SMA (SMA proper, or SMA), and, in the anterior cingulate cortex, the rostral cingulate zone (RCZ) and the caudal cingulate zone (CCZ). We used functional magnetic resonance imaging (fMRI) to examine the role of each of these mesial motor areas in self-initiated and visually triggered movements. Healthy subjects performed self-initiated movements of the right fingers (self-initiated task, SI). Each movement elicited a visual signal that was recorded. The recorded sequence of visual signals was played back, and the subjects moved the right fingers in response to each signal (visually triggered task, VT). There were two types of movements: repetitive (fixed) or sequential (sequence), performed at two different rates: slow or fast. The four regions of interest (pre-SMA, SMA, RCZ, CCZ) were traced on a high-resolution MRI of each subject’s brain. Descriptive analysis, consisting of individual assessment of significant activation, revealed a bilateral activation in the four mesial structures for all movement conditions, but SI movements were more efficient than VT movements. The more complex and more rapid the movements, the smaller the difference in activation efficiency between the SI and the VT tasks, which indicated an additional processing role of the mesial motor areas involving both the type and rate of movements. Quantitative analysis was performed on the spatial extent of the area activated and the percentage of change in signal amplitude. In the pre-SMA, activation was more extensive for SI than for VT movements, and for fast than for slow movements; the extent of activation was larger in the ipsilateral pre-SMA. In the SMA, the difference was not significant in the extent and magnitude of activation between SI and VT movements, but activation was more extensive for sequential than for fixed movements. In the RCZ and CCZ, both the extent and magnitude of activation were larger for SI than for VT movements. In the CCZ, both indices of activation were also larger for sequential than for fixed movements, and for fast than for slow movements. These data suggest functional specificities of the frontomesial motor areas with respect not only to the mode of movement initiation (self-initiated or externally triggered) but also to the movement type and rate.Keywords
This publication has 59 references indexed in Scilit:
- The functional neuroanatomy of simple and complex sequential finger movements: a PET studyBrain, 1998
- Rate Dependence of Regional Cerebral Activation during Performance of a Repetitive Motor Task: A PET StudyJournal of Cerebral Blood Flow & Metabolism, 1996
- Cerebral structures participating in motor preparation in humans: a positron emission tomography studyJournal of Neurophysiology, 1996
- A spatio-temporal dipole model of the readiness potential in humans. I. Finger movementElectroencephalography and Clinical Neurophysiology, 1994
- Bereitschaftspotential: is there a contribution of the supplementary motor area?Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section, 1993
- Regional cerebral blood flow during volitional breathing in man.The Journal of Physiology, 1991
- Cortical areas and the selection of movement: a study with positron emission tomographyExperimental Brain Research, 1991
- The origin of corticospinal projections from the premotor areas in the frontal lobeJournal of Neuroscience, 1991
- Functional mapping of the human cerebellum with positron emission tomography.Proceedings of the National Academy of Sciences, 1985
- An electrical sign of participation of the mesial ‘supplementary’ motor cortex in human voluntary finger movementBrain Research, 1978