Relationship between the velocity of illusory hand movement and strength of MEG signals in human primary motor cortex and left angular gyrus

Although previous studies have shown that activity of neurons in the motor cortex is related to various movement parameters, including the direction of movement, the spatial pattern by which these parameters are represented is still unresolved. The current work was designed to study the pattern of representation of the preferred direction (PD) of hand movement over the cortical surface. By studying pairwise PD differences, and by applying a novel implementation of the circular variance during preparation and movement periods in the context of a center-out task, we demonstrate a nonrandom distribution of PDs over the premotor and motor cortical surface of two monkeys. Our analysis shows that, whereas PDs of units recorded by nonadjacent electrodes are not more similar than expected by chance, PDs of units recorded by adjacent electrodes are. PDs of units recorded by a single electrode display the greatest similarity. Comparison of PD distributions during preparation and movement reveals that PDs of nearby units tend to be more similar during the preparation period. However, even for pairs of units recorded by a single electrode, the mean PD difference is typically large (45° and 75° during preparation and movement, respectively), so that a strictly modular representation of hand movement direction over the cortical surface is not supported by our data.

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Primary Motor Cortex Excitability Is Modulated During the Mental Simulation of Hand Movement

Journal of the International Neuropsychological Society ◽

10.1017/s1355617717000029 ◽

2017 ◽

Vol 23 (2) ◽

pp. 185-193 ◽

Cited By ~ 8

Author(s):

Christian Hyde ◽

Ian Fuelscher ◽

Jarrad A.G. Lum ◽

Jacqueline Williams ◽

Jason He ◽

...

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Motor Evoked Potentials ◽

Hand Movement ◽

Single Pulse ◽

Stimulus Presentation ◽

Mental Simulation ◽

Right Hand ◽

Hand Laterality ◽

Motor Cortex Excitability

AbstractObjectives:It is unclear whether the primary motor cortex (PMC) is involved in the mental simulation of movement [i.e., motor imagery (MI)]. The present study aimed to clarify PMC involvement using a highly novel adaptation of the hand laterality task (HLT).Methods:Participants were administered single-pulse transcranial magnetic stimulation (TMS) to the hand area of the left PMC (hPMC) at either 50 ms, 400 ms, or 650 ms post stimulus presentation. Motor-evoked potentials (MEPs) were recorded from the right first dorsal interosseous via electromyography. To avoid the confound of gross motor response, participant response (indicating left or right hand) was recorded via eye tracking. Participants were 22 healthy adults (18 to 36 years), 16 whose behavioral profile on the HLT was consistent with the use of a MI strategy (MI users).Results:hPMC excitability increased significantly during HLT performance for MI users, evidenced by significantly larger right hand MEPs following single-pulse TMS 50 ms, 400 ms, and 650 ms post stimulus presentation relative to baseline. Subsequent analysis showed that hPMC excitability was greater for more complex simulated hand movements, where hand MEPs at 50 ms were larger for biomechanically awkward movements (i.e., hands requiring lateral rotation) compared to simpler movements (i.e., hands requiring medial rotation).Conclusions:These findings provide support for the modulation of PMC excitability during the HLT attributable to MI, and may indicate a role for the PMC during MI. (JINS, 2017,23, 185–193)

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Primary motor cortex has independent representations for ipsilateral and contralateral arm movements but correlated representations for grasping

10.1101/19008128 ◽

2019 ◽

Cited By ~ 1

Author(s):

John E Downey ◽

Kristin M Quick ◽

Nathaniel Schwed ◽

Jeffrey M Weiss ◽

George F Wittenberg ◽

...

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Human Subjects ◽

Brain Computer Interface ◽

Hand Movement ◽

Arm Movement ◽

Computer Interface ◽

Contralateral Movement ◽

Contralateral Motor ◽

Continuous Movements

AbstractMotor commands for the arms and hands generally originate in contralateral motor cortex anatomically. However, ipsilateral primary motor cortex shows activity related to arm movement despite the lack of direct connections. The extent to which the activity related to ipsilateral movement is independent from that related to contralateral movement is unclear based on conflicting conclusions in prior work. Here we present the results of bilateral arm and hand movement tasks completed by two human subjects with intracortical microelectrode arrays implanted in left primary motor cortex for a clinical brain-computer interface study. Neural activity was recorded while they attempted to perform arm and hand movements in a virtual environment. This enabled us to quantify the strength and independence of motor cortical activity related to continuous movements of each arm. We also investigated the subjects’ ability to control both arms through a brain-computer interface system. Through a number of experiments, we found that ipsilateral arm movement was represented independently of, but more weakly than, contralateral arm movement. However, the representation of grasping was correlated between the two hands. This difference between hand and arm representation was unexpected, and poses new questions about the different ways primary motor cortex controls hands and arms.

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Event-related desynchronization reflects downregulation of intracortical inhibition in human primary motor cortex

Journal of Neurophysiology ◽

10.1152/jn.01092.2012 ◽

2013 ◽

Vol 110 (5) ◽

pp. 1158-1166 ◽

Cited By ~ 108

Author(s):

Mitsuaki Takemi ◽

Yoshihisa Masakado ◽

Meigen Liu ◽

Junichi Ushiba

Keyword(s):

Motor Cortex ◽

Motor Imagery ◽

Sensorimotor Cortex ◽

Primary Motor Cortex ◽

Motor Evoked Potentials ◽

Short Interval ◽

Hand Movement ◽

Intracortical Inhibition ◽

Imagery Task ◽

Event Related Desynchronization

There is increasing interest in electroencephalogram (EEG)-based brain-computer interface (BCI) as a tool for rehabilitation of upper limb motor functions in hemiplegic stroke patients. This type of BCI often exploits mu and beta oscillations in EEG recorded over the sensorimotor areas, and their event-related desynchronization (ERD) following motor imagery is believed to represent increased sensorimotor cortex excitability. However, it remains unclear whether the sensorimotor cortex excitability is actually correlated with ERD. Thus we assessed the association of ERD with primary motor cortex (M1) excitability during motor imagery of right wrist movement. M1 excitability was tested by motor evoked potentials (MEPs), short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF) with transcranial magnetic stimulation (TMS). Twenty healthy participants were recruited. The participants performed 7 s of rest followed by 5 s of motor imagery and received online visual feedback of the ERD magnitude of the contralateral hand M1 while performing the motor imagery task. TMS was applied to the right hand M1 when ERD exceeded predetermined thresholds during motor imagery. MEP amplitudes, SICI, and ICF were recorded from the agonist muscle of the imagined hand movement. Results showed that the large ERD during wrist motor imagery was associated with significantly increased MEP amplitudes and reduced SICI but no significant changes in ICF. Thus ERD magnitude during wrist motor imagery represents M1 excitability. This study provides electrophysiological evidence that a motor imagery task involving ERD may induce changes in corticospinal excitability similar to changes accompanying actual movements.

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Functional Connectivity Between Secondary and Primary Motor Areas Underlying Hand–Foot Coordination

Journal of Neurophysiology ◽

10.1152/jn.00325.2007 ◽

2007 ◽

Vol 98 (1) ◽

pp. 414-422 ◽

Cited By ~ 64

Author(s):

Winston D. Byblow ◽

James P. Coxon ◽

Cathy M. Stinear ◽

Melanie K. Fleming ◽

Garry Williams ◽

...

Keyword(s):

Functional Connectivity ◽

Motor Cortex ◽

Muscle Activation ◽

Primary Motor Cortex ◽

Premotor Cortex ◽

Hand Movement ◽

Physiological Basis ◽

Activation Conditions ◽

Motor Representations ◽

Motor Areas

Coincident hand and foot movements are more reliably performed in the same direction than in opposite directions. Using transcranial magnetic stimulation (TMS) to assess motor cortex function, we examined the physiological basis of these movements across three novel experiments. Experiment 1 demonstrated that upper limb corticomotor excitability changed in a way that facilitated isodirectional movements of the hand and foot, during phasic and isometric muscle activation conditions. Experiment 2 demonstrated that motor cortex inhibition was modified with active, but not passive, foot movement in a manner that facilitated hand movement in the direction of foot movement. Together, these findings demonstrate that the coupling between motor representations within motor cortex is activity dependent. Because there are no known connections between hand and foot areas within primary motor cortex, experiment 3 used a dual-coil paired-pulse TMS protocol to examine functional connectivity between secondary and primary motor areas during active ankle dorsiflexion and plantarflexion. Dorsal premotor cortex (PMd) and supplementary motor area (SMA) conditioning, but not ventral premotor cortex (PMv) conditioning, produced distinct phases of task-dependent modulation of excitability of forearm representations within primary motor cortex (M1). Networks involving PMd–M1 facilitate isodirectional movements of hand and foot, whereas networks involving SMA–M1 facilitate corticomotor pathways nonspecifically, which may help to stabilize posture during interlimb coordination. These results may have implications for targeted neurorehabilitation after stroke.

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MRI correlates of clinical disability and hand-motor performance in multiple sclerosis phenotypes

Multiple Sclerosis Journal ◽

10.1177/1352458520958356 ◽

2020 ◽

pp. 135245852095835

Author(s):

Claudio Cordani ◽

Milagros Hidalgo de la Cruz ◽

Alessandro Meani ◽

Paola Valsasina ◽

Federica Esposito ◽

...

Keyword(s):

Multiple Sclerosis ◽

Motor Cortex ◽

Functional Mri ◽

Structural Damage ◽

Primary Motor Cortex ◽

Inferior Frontal Gyrus ◽

Hand Movement ◽

Motor Impairment ◽

Left Hand ◽

Mri Scans

Background: Hand-motor impairment affects a large proportion of multiple sclerosis (MS) patients; however, its substrates are still poorly understood. Objectives: To investigate the association between global disability, hand-motor impairment, and alterations in motor-relevant structural and functional magnetic resonance imaging (MRI) networks in MS patients with different clinical phenotypes. Methods: One hundred thirty-four healthy controls (HC) and 364 MS patients (250 relapsing-remitting MS (RRMS) and 114 progressive MS (PMS)) underwent Expanded Disability Status Scale (EDSS) rating, nine-hole peg test (9HPT), and electronic finger tapping rate (EFTR). Structural and resting state (RS) functional MRI scans were used to perform a source-based morphometry on gray matter (GM) components, to analyze white matter (WM) tract diffusivity indices and to perform a RS seed-based approach from the primary motor cortex involved in hand movement (hand-motor cortex). Random forest analyses identified the predictors of clinical impairment. Result: In RRMS, global measures of atrophy and lesions together with measures of structural damage of motor-related regions predicted EDSS (out-of-bag (OOB)- R2 = 0.19, p-range = <0.001–0.04), z9HPT (right: OOB- R2 = 0.14; left: OOB- R2 = 0.24, p-range = <0.001–0.03). No RS functional connectivity (FC) abnormalities were identified in RRMS models. In PMS, cerebellar and sensorimotor regions atrophy, cerebellar peduncles integrity and increased RS FC between left hand-motor cortex and right inferior frontal gyrus predicted EDSS (OBB- R2 = 0.16, p-range = 0.02–0.04). Conclusion: In RRMS, only measures of structural damage contribute to explain motor impairment, whereas both structural and functional MRI measures predict clinical disability in PMS. A multiparametric MRI approach could be relevant to investigate hand-motor impairment in different MS phenotypes.

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Response-Dependent Contributions of Human Primary Motor Cortex and Angular Gyrus to Manual and Perceptual Sequence Learning

Journal of Neuroscience ◽

10.1523/jneurosci.2603-09.2009 ◽

2009 ◽

Vol 29 (48) ◽

pp. 15115-15125 ◽

Cited By ~ 39

Author(s):

C. R. Rosenthal ◽

E. E. Roche-Kelly ◽

M. Husain ◽

C. Kennard

Keyword(s):

Motor Cortex ◽

Sequence Learning ◽

Primary Motor Cortex ◽

Angular Gyrus

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Interhemispheric interactions between the right angular gyrus and the left motor cortex: a transcranial magnetic stimulation study

Journal of Neurophysiology ◽

10.1152/jn.00642.2020 ◽

2021 ◽

Author(s):

Julianne Baarbé ◽

Michael Vesia ◽

Matt Brown ◽

Karlo J. Lizarraga ◽

Carolyn A Gunraj ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Posterior Parietal Cortex ◽

Short Interval ◽

Intracortical Inhibition ◽

Angular Gyrus ◽

Posterior Parietal ◽

The Right ◽

Left Angular Gyrus

The interconnection of the angular gyrus of right posterior parietal cortex (PPC) and the left motor cortex (LM1) is essential for goal-directed hand movements. Previous work with transcranial magnetic stimulation (TMS) showed that right PPC stimulation increases LM1 excitability but right PPC followed by left PPC-LM1 stimulation (LPPC-LM1) inhibits LM1 corticospinal output compared to LPPC-LM1 alone. It is not clear if right PPC-mediated inhibition of LPPC-LM1 is due to inhibition of left PPC or to combined effects of right and left PPC stimulation on LM1 excitability. We used paired-pulse TMS to study the extent to which combined right and left PPC stimulation, targeting the angular gyri, influences LM1 excitability. We tested 16 healthy subjects in five paired-pulsed TMS experiments using MRI-guided neuronavigation to target the angular gyri within PPC. We tested the effects of different right angular gyrus (RAG) and LM1 stimulation intensities on the influence of RAG on LM1 and on influence of left angular gyrus (LAG) on LM1 (LAG-LM1). We then tested the effects of RAG and LAG stimulation on LM1 short-interval intracortical facilitation(SICF), short-interval intracortical inhibition(SICI) and long-interval intracortical inhibition(LICI). The results revealed that RAG facilitated LM1, inhibited SICF and inhibited LAG-LM1. Combined RAG-LAG stimulation did not affect SICI but increased LICI. These experiments suggest that RAG-mediated inhibition of LAG-LM1 is related to inhibition of early I-wave activity and enhancement of GABAB receptor-mediated inhibition in LM1. The influence of RAG on LM1 likely involves ipsilateral connections from LAG to LM1 and heterotopic connections from RAG to LM1.

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An output zone of the monkey primary motor cortex specialized for bilateral hand movement

Experimental Brain Research ◽

10.1007/bf00230856 ◽

1990 ◽

Vol 82 (1) ◽

Cited By ~ 71

Author(s):

H. Aizawa ◽

H. Mushiake ◽

M. Inase ◽

J. Tanji

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Hand Movement

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A computational model based on cortico-spinal fMRI for asymmetrically organized motor corticospinal networks in humans

10.21203/rs.3.rs-308675/v1 ◽

2021 ◽

Author(s):

Eiji Takasawa ◽

Mitsunari Abe ◽

Kenji Takagishi ◽

Hirotaka Chikuda ◽

Takashi Hanakawa

Keyword(s):

Motor Cortex ◽

Primary Motor Cortex ◽

Hand Movement ◽

Hand Preference ◽

Synaptic Connections ◽

Spinal Motoneurons ◽

Functional Magnetic Resonance ◽

Hand Dexterity ◽

Spinal Fmri ◽

Dexterous Hand

Abstract Evolution of the direct connection from primary motor cortex to motoneurons in the spinal cord parallels acquisition of hand dexterity and lateralization of hand preference. Recent studies indicated that the phylogenetically older pathway consisting of multi-synaptic connections from primary motor cortex to spinal motoneurons also participate in controlling dexterous hand movement. However, it remains unknown how the two corticospinal pathways work in concert to control unilateral hand movement with lateralized preference. Using corticospinal functional magnetic resonance imaging, we discovered the asymmetric organization of the two corticospinal networks that modelled monosynaptic or polysynaptic control from primary motor cortices over spinal motoneurons. Moreover, the degree of the involvement of the two corticospinal networks paralleled the lateralization of hand preference. The present results pointed to the functionally lateralized motor nervous system that underlies the behavioural asymmetry of handedness, a uniquely human trait which could have phylogenetically differentiated humans from other primates.

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