Activity Properties and Location of Neurons in the Motor Thalamus That Project to the Cortical Motor Areas in Monkeys

2005 ◽  
Vol 94 (1) ◽  
pp. 550-566 ◽  
Author(s):  
Kiyoshi Kurata
Keyword(s):  
Primary Motor Cortex ◽  
Movement Time ◽  
Premotor Cortex ◽  
Direction Selectivity ◽  
Related Activity ◽  
Cortical Motor ◽  
Somatosensory Stimulus ◽  
Preparation Period ◽  
Sustained Change ◽  
Motor Areas

The activity of neurons in the motor nuclei of the thalamus that project to the cortical motor areas (the primary motor cortex, the ventral and dorsal premotor cortex, and the supplementary motor area) was investigated in monkeys that were performing a task in which wrist extension and flexion movements were instructed by visuospatial cues before the onset of movement. Movement was triggered by a visual, auditory, or somatosensory stimulus. Thalamocortical neurons were identified by a spike collision, and exhibited 2 distinct types of task-related activity: 1) a sustained change in activity during the instructed preparation period in response to the instruction cues (set-related activity); and 2) phasic changes in activity during the reaction and movement time periods (movement-related activity). A number of set- and moment-related neurons exhibited direction selectivity. Most movement-related neurons were similarly active, irrespective of the different sensory modalities of the cue for movement. These properties of neuronal activity were similar, regardless of their target cortical motor areas. There were no significant differences in the antidromic latencies of neurons that projected to the primary and nonprimary motor areas. These results suggest that the thalamocortical neurons play an important role in the preparation for, and initiation and execution of, the movements, but are less important than neurons of the nonprimary cortical motor areas in modality-selective sensorimotor transformation. It is likely that such transformations take place within the nonprimary cortical motor areas, but not through thalamocortical information channels.

Effects of a Body-oriented Response Measure on the Neural Substrate of Imagined Perspective Rotations

2010 ◽  
Vol 22 (8) ◽  
pp. 1782-1793 ◽  
Author(s):  
Maryjane Wraga ◽  
Catherine M. Flynn ◽  
Holly K. Boyle ◽  
Gretchen C. Evans
Keyword(s):  
Primary Motor Cortex ◽  
Premotor Cortex ◽  
The Body ◽  
Neural Activation ◽  
Low Level ◽  
Cortical Motor ◽  
Behavioral Studies ◽  
Object Part ◽  
Response Measures ◽  
Motor Areas

Previous behavioral studies suggest that response measures related to the body, such as pointing, serve to anchor participants to their physical body during mental rotation tasks in which their perspective must be shifted elsewhere. This study investigated whether such measures engage spatial and low-level cortical motor areas of the brain more readily than non-body-related measures. We directly compared activation found in two imagined perspective rotation tasks, using responses that varied in the degree to which they emphasized the human body. In the body minimize condition, participants imagined rotating themselves around an object and judged whether a prescribed part of the object would be visible from the imagined viewpoint. In the body maximize condition, participants imagined rotating around the object and then located the prescribed object part with respect to their bodies. A direct comparison of neural activation in both conditions revealed distinct yet overlapping neural regions. The body maximize condition yielded activation in low-level cortical motor areas such as premotor cortex and primary motor cortex, as well as bilateral spatial processing areas. The body minimize condition yielded activation in nonmotoric egocentric processing regions. However, both conditions showed activation in the parietal–occipital region that is thought to be involved in egocentric transformations. These findings are discussed in the context of recent hypotheses regarding the role of the body percept in imagined egocentric transformations.

Laterality of Movement-Related Activity Reflects Transformation of Coordinates in Ventral Premotor Cortex and Primary Motor Cortex of Monkeys

2007 ◽  
Vol 98 (4) ◽  
pp. 2008-2021 ◽  
Author(s):  
Kiyoshi Kurata
Keyword(s):  
Motor Cortex ◽  
Neuronal Activity ◽  
Primary Motor Cortex ◽  
Premotor Cortex ◽  
Visuomotor Transformation ◽  
Related Activity ◽  
Reaching Task ◽  
Ventral Premotor Cortex ◽  
Cortical Motor ◽  
Target Locations

The ventral premotor cortex (PMv) and the primary motor cortex (MI) of monkeys participate in various sensorimotor integrations, such as the transformation of coordinates from visual to motor space, because the areas contain movement-related neuronal activity reflecting either visual or motor space. In addition to relationship to visual and motor space, laterality of the activity could indicate stages in the visuomotor transformation. Thus we examined laterality and relationship to visual and motor space of movement-related neuronal activity in the PMv and MI of monkeys performing a fast-reaching task with the left or right arm, toward targets with visual and motor coordinates that had been dissociated by shift prisms. We determined laterality of each activity quantitatively and classified it into four types: activity that consistently depended on target locations in either head-centered visual coordinates (V-type) or motor coordinates (M-type) and those that had either differential or nondifferential activity for both coordinates (B- and N-types). A majority of M-type neurons in the areas had preferences for reaching movements with the arm contralateral to the hemisphere where neuronal activity was recorded. In contrast, most of the V-type neurons were recorded in the PMv and exhibited less laterality than the M-type. The B- and N-types were recorded in the PMv and MI and exhibited intermediate properties between the V- and M-types when laterality and correlations to visual and motor space of them were jointly examined. These results suggest that the cortical motor areas contribute to the transformation of coordinates to generate final motor commands.

Multiple Nonprimary Motor Areas in the Human Cortex

1997 ◽  
Vol 77 (4) ◽  
pp. 2164-2174 ◽  
Author(s):  
Gereon R. Fink ◽  
Richard S. J. Frackowiak ◽  
Uwe Pietrzyk ◽  
Richard E. Passingham
Keyword(s):  
Motor Cortex ◽  
Somatosensory Cortex ◽  
Primary Motor Cortex ◽  
Premotor Cortex ◽  
Motor Area ◽  
Related Activity ◽  
Human Cortex ◽  
Premotor Area ◽  
Cingulate Motor Area ◽  
Motor Areas

Fink, Gereon R., Richard S. J. Frackowiak, Uwe Pietrzyk, and Richard E. Passingham. Multiple nonprimary motor areas in the human cortex. J. Neurophysiol. 77: 2164–2174, 1997. We measured the distribution of regional cerebral blood flow with positron emission tomography while three subjects moved their hand, shoulder, or leg. The images were coregistered with each individual's anatomic magnetic resonance scans. The data were analyzed for each individual to avoid intersubject averaging and so to preserve individual gyral anatomy. Instead of inspecting all pixels, we prospectively restricted the data analysis to particular areas of interest. These were defined on basis of the anatomic and physiological literature on nonhuman primates. By examining only a subset of areas, we strengthened the power of the statistical analysis and thereby increased the confidence in reporting single subject data. On the lateral convexity, motor related activity was found for all three subjects in the primary motor cortex, lateral premotor cortex, and an opercular area within the premotor cortex. In addition, there was activation of somatosensory cortex (SI), the supplementary somatosensory area (SII) in the Sylvian fissure, and parietal association areas (Brodmann areas 5 and 40). There was also activation in the insula. We suggest that the activation in the dorsal premotor cortex may correspond with dorsal premotor area (PMd) as described in the macaque brain. We propose three hypotheses as to the probable location of vental premotor area (PMv) in the human brain. On the medial surface, motor-related activity was found for all three subjects in the leg areas of the primary motor cortex and somatosensory cortex and also activity for the hand, shoulder, and leg in the supplementary motor area (SMA) on the dorsal medial convexity and in three areas in the cingulate sulcus. We suggest that the three cingulate areas may correspond with rostral cingulate premotor area, dorsal cingulate motor area (CMAd), and ventral cingulate motor area (CMAv) as identified in the macaque brain. Somatotopic mapping was demonstrated in the primary motor and primary somatosensory cortex. In all three subjects, the arm region lay anterior to the leg region in parietal area 5. Also in all three subjects, the arm region lay anterior to the leg region in the supplementary motor cortex.

Neuronal Activity in the Ventral Part of Premotor Cortex During Target-Reach Movement is Modulated by Direction of Gaze

1997 ◽  
Vol 78 (1) ◽  
pp. 567-571 ◽  
Author(s):  
Hajime Mushiake ◽  
Yasuyuki Tanatsugu ◽  
Jun Tanji
Keyword(s):  
Neuronal Activity ◽  
Primary Motor Cortex ◽  
Premotor Cortex ◽  
Motor Command ◽  
Direction Selectivity ◽  
Fixation Target ◽  
Ventral Part ◽  
Related Activity ◽  
Reaching Task ◽  
Command Signals

Mushiake, Hajime, Yasuyuki Tanatsugu, and Jun Tanji. Neuronal activity in the ventral part of premotor cortex during target-reach movement is modulated by direction of gaze. J. Neurophysiol. 78: 567–571, 1997. We recorded 200 neurons from the ventral part of the premotor cortex (PMv) and 110 neurons from the primary motor cortex (MI) of a monkey performing a visually cued arm-reaching task with a delay. We compared neuronal activity in the premovement period while the monkey reached the target with the eyes fixating on either a left or right fixation target. Our data demonstrate that about half of the movement-related activity in the PMv was modulated by the direction of gaze. In contrast, a vast majority of the activity of MI neurons and about half of PMv neurons were not influenced by the direction of gaze. We further analyzed the movement-related activity during the reaching movement to targets at the top, bottom, left, and right of each fixation point. The magnitude of activity of neurons showing the gaze-direction selectivity was primarily determined by the position of the reaching target relative to the eye-fixation target, and not by the position of the target relative to the animal's body. These data suggest that a part of the coordinate transformation of the motor command signals concerning the direction of reaching from the retinotopic to body-centered frame of reference may occur at the level of premotor cortex but not in MI.

Movement Sequence-Related Activity Reflecting Numerical Order of Components in Supplementary and Presupplementary Motor Areas

1998 ◽  
Vol 80 (3) ◽  
pp. 1562-1566 ◽  
Author(s):  
William T. Clower ◽  
Garrett E. Alexander
Keyword(s):  
Movement Time ◽  
Electromyographic Activity ◽  
Related Activity ◽  
Spatial Variables ◽  
Movement Sequence ◽  
Sequence Components ◽  
Numerical Order ◽  
Relational Order ◽  
Sequencing Task ◽  
Motor Areas

Clower, William T. and Garrett E. Alexander. Movement sequence-related activity reflecting numerical order of components in supplementary and presupplementary motor areas. J. Neurophysiol. 80: 1562–1566, 1998. The supplementary motor area (SMA) and presupplementary motor areas (pre-SMA) have been implicated in movement sequencing, and neurons in SMA have been shown to encode what might be termed the relational order among sequence components (e.g., movement X followed by movement Y). To determine whether other aspects of movement sequencing might also be encoded by SMA or pre-SMA neurons, we analyzed task-related activity recorded from both areas in conjunction with a sequencing task that dissociated the numerical order of components (e.g., movement X as the 2nd component, irrespective of which movements precede or follow X). Sequences were constructed from eight component movements, each characterized by three spatial variables (origin, direction, and endpoint). Task-related activity recorded from 56 SMA and 63 pre-SMA neurons was categorized according to both the epoch (delay, reaction time, and movement time) and the spatial variable or component movement with which it was associated. All but one instance of task-related activity was selective for one of the spatial variables (SV-selective) rather than for any of the component movements themselves. Of 110 instances of SV-selective activity in SMA, 43 (39%) showed significant effects of numerical order. The corresponding incidence in pre-SMA, 82 (71%) of 116, was substantially higher ( P < 0.00001). No effects of numerical order were evident among the hand paths, movement times, or electromyographic activity associated with task performance. We concluded that neurons in SMA and pre-SMA may encode the numerical order of components, at least for sequences that are distinguished mainly by that aspect of component ordering.

Studio funzionale RM delle aree motorie corticali nel morbo di Parkinson

1997 ◽  
Vol 10 (2_suppl) ◽  
pp. 21-24 ◽  
Author(s):  
G.P. Pelliccioli ◽  
O. Presciutti ◽  
N. Tambasco ◽  
P. Floridi ◽  
R. Tarducci ◽  
...  
Keyword(s):  
Primary Motor Cortex ◽  
Motor Task ◽  
Activation Pattern ◽  
Fixed Sequence ◽  
Dopaminergic Drugs ◽  
Cortical Motor ◽  
Major Increase ◽  
And Performance ◽  
Mri Study ◽  
Motor Areas

Impaired motor programming and performance in Parkinson's Disease (PD) is related to a functional deafferentation from the basal ganglia to the cortical motor areas, which can be partially reversed by dopaminergic drugs. The aim of this functional MRI study was to compare the activation pattern of motor areas in early PD patients on therapy versus age-matched controls and to show how the dopaminergic drug apomorphine modifies this activation pattern. The self-paced motor task was a complex fixed sequence of finger movements in opposition to the thumb. Comparison between whole activation of cortical motor areas in patients and controls revealed no significant differences. In patients a significant reduction of the activation was found in the primary motor cortex contralateral to the more affected hand; on the contrary a major increase in activation in the same motor area was observed after apomorphine. This could be evidence of the reversal of the partial deafferentation due to the direct dopaminergic action of apomorphine which is complementary to levodopa.

scholarly journals The Cortical Motor System in the Domestic Pig: Origin and Termination of the Corticospinal Tract and Cortico-Brainstem Projections

2021 ◽  
Vol 15 ◽  
Author(s):  
Patricia del Cerro ◽  
Ángel Rodríguez-De-Lope ◽  
Jorge E. Collazos-Castro
Keyword(s):  
Spinal Cord ◽  
Motor System ◽  
Primary Motor Cortex ◽  
Corticospinal Tract ◽  
Premotor Cortex ◽  
Mesencephalic Reticular Formation ◽  
Reticular Nucleus ◽  
Descending Pathways ◽  
Spinal Segment ◽  
Cortical Motor

The anatomy of the cortical motor system and its relationship to motor repertoire in artiodactyls is for the most part unknown. We studied the origin and termination of the corticospinal tract (CST) and cortico-brainstem projections in domestic pigs. Pyramidal neurons were retrogradely labeled by injecting aminostilbamidine in the spinal segment C1. After identifying the dual origin of the porcine CST in the primary motor cortex (M1) and premotor cortex (PM), the axons descending from those regions to the spinal cord and brainstem were anterogradely labeled by unilateral injections of dextran alexa-594 in M1 and dextran alexa-488 in PM. Numerous corticospinal projections from M1 and PM were detected up to T6 spinal segment and showed a similar pattern of decussation and distribution in the white matter funiculi and the gray matter laminae. They terminated mostly on dendrites of the lateral intermediate laminae and the internal basilar nucleus, and some innervated the ventromedial laminae, but were essentially absent in lateral laminae IX. Corticofugal axons terminated predominantly ipsilaterally in the midbrain and bilaterally in the medulla oblongata. Most corticorubral projections arose from M1, whereas the mesencephalic reticular formation, superior colliculus, lateral reticular nucleus, gigantocellular reticular nucleus, and raphe received abundant axonal contacts from both M1 and PM. Our data suggest that the porcine cortical motor system has some common features with that of primates and humans and may control posture and movement through parallel motor descending pathways. However, less cortical regions project to the spinal cord in pigs, and the CST neither seems to reach the lumbar enlargement nor to have a significant direct innervation of cervical, foreleg motoneurons.

The Cortical Motor Areas and the Emergence of Motor Skills: A Neuroanatomical Perspective

2021 ◽  
Vol 44 (1) ◽  
Author(s):  
Peter L. Strick ◽  
Richard P. Dum ◽  
Jean-Alban Rathelot
Keyword(s):  
Motor Skills ◽  
Primary Motor Cortex ◽  
Annual Review ◽  
Publication Date ◽  
Motor Tasks ◽  
Motor Behaviors ◽  
Cortical Motor ◽  
Neural Substrate ◽  
Spatiotemporal Coordination ◽  
Motor Areas

What changes in neural architecture account for the emergence and expansion of dexterity in primates? Dexterity, or skill in performing motor tasks, depends on the ability to generate highly fractionated patterns of muscle activity. It also involves the spatiotemporal coordination of activity in proximal and distal muscles across multiple joints. Many motor skills require the generation of complex movement sequences that are only acquired and refined through extensive practice. Improvements in dexterity have enabled primates to manufacture and use tools and humans to engage in skilled motor behaviors such as typing, dance, musical performance, and sports. Our analysis leads to the following synthesis: The neural substrate that endows primates with their enhanced motor capabilities is due, in part, to ( a) major organizational changes in the primary motor cortex and ( b) the proliferation of output pathways from other areas of the cerebral cortex, especially from the motor areas on the medial wall of the hemisphere. Expected final online publication date for the Annual Review of Neuroscience, Volume 44 is July 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Movement-Related Neuronal Activity Reflecting the Transformation of Coordinates in the Ventral Premotor Cortex of Monkeys

2002 ◽  
Vol 88 (6) ◽  
pp. 3118-3132 ◽  
Author(s):  
Kiyoshi Kurata ◽  
Eiji Hoshi
Keyword(s):  
Neuronal Activity ◽  
Primary Motor Cortex ◽  
Linear Models ◽  
Target Location ◽  
Movement Time ◽  
Premotor Cortex ◽  
Visual Space ◽  
Behavioral Task ◽  
Movement Onset ◽  
Ventral Premotor Cortex

We examined how the transformation of coordinates from visual to motor space is reflected by neuronal activity in the ventral premotor cortex (PMv) of monkeys. Three monkeys were trained to reach with their right hand for a target that appeared on a screen. While performing the task, the monkeys wore prisms that shifted the image of the target 10°, left or right, or wore no prisms, for a block of 200 trials. The nine targets were located in the same positions in visual space regardless of whether the prisms were present. Wearing the prisms required the monkeys to initiate a movement in a direction that was different from the apparent target location. Thus using the prisms, we could dissociate visual space from motor space. While the monkey performed the behavioral task, we recorded neuronal activity in the left PMv and primary motor cortex (MI), and various kinds of task-related neuronal activity were found in the motor areas. These included neurons that changed their activity during a reaction time (RT) period (the period between target presentation and movement onset), which were called “movement-related neurons” and selected for analysis. In these neurons, activity during a movement time (MT) period was also compared. Using general linear models for our statistical analysis, the neurons were then classified into four types: those whose activity was consistently dependent on location of targets in the visual coordinates regardless of whether the prisms were present or absent (V type); those that were consistently dependent on target location in the motor coordinates only; those that had different activity for both of the motor and visual coordinates; and those that had nondifferential activity for the two types of coordinates. The proportion of the four types of the neurons differed significantly between the PMv and MI. Most remarkably, neurons with V-type activity were almost exclusively recorded in the PMv and were almost exclusively found during the RT period. Such activity was never observed in an electromyogram of the working forelimb. Based on these observations, we postulate that the V and other types may represent the various intermediate stages of the transformation of coordinates and that the PMv plays a crucial role in transforming coordinates from visual to motor space.

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