SUMMARIES OF PRESENTATIONS ON THE NEURAL MECHANISMS OF VOLUNTARY MOVEMENTS AND PRECENTRAL MOTOR AREA

We describe the case of a computer operator who experienced paroxysmal attacks several times in which she felt a compulsion to handle keys with her right hand or actually her right hand moved involuntarily in a key-handling rhythm. Cranial CT and MRI revealed a mass lesion in the left medial aspect of the frontal lobe (supplementary motor area). After the removal of this tumor (meningioma), there were no more paroxysmal attacks. We suggest that voluntary movements controlled by the supplementary motor area were deranged by seizures provoked by the tumor. This case is attractive in relation to obsessive-compulsive disorder.

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The cortical potential related to sensory feedback from voluntary movements shows somatotopic organization of the supplementary motor area

Brain Topography ◽

10.1007/bf01129638 ◽

1991 ◽

Vol 3 (3) ◽

pp. 359-363 ◽

Cited By ~ 13

Author(s):

I. M. Tarkka ◽

M. Hallett

Keyword(s):

Sensory Feedback ◽

Supplementary Motor Area ◽

Cortical Potential ◽

Motor Area ◽

Voluntary Movements ◽

Somatotopic Organization

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Different cortical areas in man in organization of voluntary movements in extrapersonal space

Journal of Neurophysiology ◽

10.1152/jn.1980.43.1.137 ◽

1980 ◽

Vol 43 (1) ◽

pp. 137-150 ◽

Cited By ~ 321

Author(s):

P. E. Roland ◽

E. Skinhoj ◽

N. A. Lassen ◽

B. Larsen

Keyword(s):

Blood Flow ◽

Motor Program ◽

Motor Area ◽

Auditory Information ◽

Frontal Eye Fields ◽

Voluntary Movements ◽

Mental Work ◽

Verbal Command ◽

Maze Test ◽

Extrapersonal Space

1. This paper reports regional cerebral blood flow (rCBF) measurements in 254 cortical regions with 133Xe injected into the internal carotid artery in 19 patients, none of whom had any major neurological defect. The purpose was to demonstrate the pattern of cortical activity, as revealed by rCBF increases, during two types of unilateral voluntary movement in extrapersonal space: a) the maze test, series of fast isolated movements in various directions in a frame, executed under verbal command; and b) the drawing of a spiral in the air. 2. Both types of movements were associated with increases of rCBF in the supplementary motor area (bilaterally), the convexity part of the premotor area (bilaterally), the primary sensorimotor hand and arm area (contralaterally), and in the superior and inferior parietal region (bilaterally). 3. During the maze test there were, in addition, bilateral focal increases of the blood flow in the auditory areas, the inferior frontal regions, and the frontal eye fields. 4. It is concluded that the supplementary motor areas, which are also active during programming and execution of movement sequences in intrapersonal space (33), elaborate programs for motor subroutines necessary in skilled voluntary motion. The convexity parts of the premotor areas are activated when a new motor program is established or a previously learned motor program is modulated. The primary motor area is the exclusive executive locus for voluntary movements of the hand and arm. 5. Voluntary movements in extrapersonal space only are associated with activation of the parietal regions. These areas are assumed to provide information to the motor programming neurons about the demanded direction of motion in extrapersonal space in relation to proprioceptive reference systems. 6. The increase of rCBF in the auditory areas, the inferior frontal regions, and the frontal eye fields during the maze test were ascribed to the processing of auditory information. 7. Both tests are accompanied by a diffuse increase of the hemispheric blood flow (approximately 10%), which is assumed to be a parallel to the commonly known desynchronization of the EEG during mental work.

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Supplementary motor area and other cortical areas in organization of voluntary movements in man

Journal of Neurophysiology ◽

10.1152/jn.1980.43.1.118 ◽

1980 ◽

Vol 43 (1) ◽

pp. 118-136 ◽

Cited By ~ 981

Author(s):

P. E. Roland ◽

B. Larsen ◽

N. A. Lassen ◽

E. Skinhoj

Keyword(s):

Blood Flow ◽

Metabolic Rate ◽

Supplementary Motor Area ◽

Motor Area ◽

Voluntary Movements ◽

Motor Sequence ◽

Primary Motor Area ◽

Cerebral Metabolic Rate ◽

Hand Area ◽

Motor Areas

1. Previous studies in man have revealed a coupling between the regional cerebral blood flow (rCBF) and the regional cerebral metabolic rate for oxygen. In normal man, increases in the regional cerebral metabolic rate for oxygen leads to proportional increases in the rCBF(34). We have measured the rCBF as an expression of the level of cortical activity simultaneously from 254 cortical regions in 28 patients with no major neurological defects, during rest and during planning and execution of a few types of learned voluntary movements with the hand. 2. We found that the rCBF increases exclusively in the supplementary motor area while subjects were programming a sequence of fast isolated movements of individual fingers, without actually executing it. 3. During execution of the same motor sequence, there were equivalent increases of the rCBF in both supplementary motor areas, but only in the contralateral primary motor area. In addition, there were more modest rCBF increases in the contralateral sensory hand area, the convexity part of the premotor area, and bilaterally in the inferior frontal region. 4. Repetitive fast flexions of the same finger or a sustained isometric muscular contraction raise the blood flow in the contralateral primary motor and sensory hand area. 5. A pure somatosensory discrimination of the shapes of objects, without any concomitant voluntary movements, also leaves the supplementary motor areas silent. 6. We conclude that the primary motor area and the part of the motor system it projects to by itself can control ongoing simple ballistic movements with the self-same body part. A sequence of different isolated finger movements requires programming in the supplementary motor areas. We suggest that the supplementary motor areas are programming areas for motor subroutines and that these areas form a queue of time-ordered motor commands before voluntary movement are executed by way of the primary motor area.

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Goal-dependent tuning of muscle spindle receptors during movement preparation

10.1101/2020.03.06.981530 ◽

2020 ◽

Cited By ~ 1

Author(s):

Stylianos Papaioannou ◽

Michael Dimitriou

Keyword(s):

Muscle Spindle ◽

Muscle Afferents ◽

Human Muscle ◽

Neural Mechanisms ◽

Voluntary Movements ◽

Movement Preparation ◽

Manual Task ◽

Spindle Bearing ◽

Preparatory Activity ◽

Arm Muscles

AbstractVoluntary movements are believed to be advantageously prepared before they are executed, but the neural mechanisms at work have been unclear. For example, there are no overt changes in skeletal muscle activity during movement preparation. Here, using a delayed-reach manual task, we demonstrate a decrease in the firing rate of human muscle afferents (primary spindles) when preparing stretch rather than shortening of the spindle-bearing muscle. This goal-dependent modulation of proprioceptors begun early after target onset but was markedly stronger at the latter parts of the preparatory period. In two additional experiments, whole-arm perturbations during reach preparation revealed a congruent modulation of stretch reflex gains of shoulder and upper arm muscles. Our study shows that movement preparation can involve sensory elements of the peripheral nervous system. We suggest that central preparatory activity can also reflect sensory control, and preparatory tuning of muscle spindle mechanoreceptors is a component of planned reaching movements.

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