Propriospinal Transmission of Descending Motor Commands

Traditional brain–machine interfaces decode cortical motor commands to control external devices. These commands are the product of higher-level cognitive processes, occurring across a network of brain areas, that integrate sensory information, plan upcoming motor actions, and monitor ongoing movements. We review cognitive signals recently discovered in the human posterior parietal cortex during neuroprosthetic clinical trials. These signals are consistent with small regions of cortex having a diverse role in cognitive aspects of movement control and body monitoring, including sensorimotor integration, planning, trajectory representation, somatosensation, action semantics, learning, and decision making. These variables are encoded within the same population of cells using structured representations that bind related sensory and motor variables, an architecture termed partially mixed selectivity. Diverse cognitive signals provide complementary information to traditional motor commands to enable more natural and intuitive control of external devices.

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Consistency influences altered auditory feedback processing

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021819838939 ◽

2019 ◽

Vol 72 (10) ◽

pp. 2371-2379 ◽

Cited By ~ 3

Author(s):

Matthias K Franken ◽

Daniel J Acheson ◽

James M McQueen ◽

Peter Hagoort ◽

Frank Eisner

Keyword(s):

Motor Control ◽

Speech Production ◽

Auditory Feedback ◽

Speech Motor Control ◽

Short Term ◽

Feedback Processing ◽

Motor Commands ◽

Consistent Condition ◽

Consistency Effect ◽

Speech Motor

Previous research on the effect of perturbed auditory feedback in speech production has focused on two types of responses. In the short term, speakers generate compensatory motor commands in response to unexpected perturbations. In the longer term, speakers adapt feedforward motor programmes in response to feedback perturbations, to avoid future errors. The current study investigated the relation between these two types of responses to altered auditory feedback. Specifically, it was hypothesised that consistency in previous feedback perturbations would influence whether speakers adapt their feedforward motor programmes. In an altered auditory feedback paradigm, formant perturbations were applied either across all trials (the consistent condition) or only to some trials, whereas the others remained unperturbed (the inconsistent condition). The results showed that speakers’ responses were affected by feedback consistency, with stronger speech changes in the consistent condition compared with the inconsistent condition. Current models of speech-motor control can explain this consistency effect. However, the data also suggest that compensation and adaptation are distinct processes, which are not in line with all current models.

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Superposition of the motor commands during creation of static efforts by human hand muscles

Fiziolohichnyĭ zhurnal ◽

10.15407/fz58.01.043 ◽

2012 ◽

Vol 58 (1) ◽

pp. 43-50 ◽

Cited By ~ 1

Author(s):

IV Vereshchaka ◽

◽

AV. Horkovenko ◽

Keyword(s):

Human Hand ◽

Hand Muscles ◽

Motor Commands

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Motor learning and transfer: from feedback to feedforward control

10.1101/845933 ◽

2019 ◽

Author(s):

Rodrigo S. Maeda ◽

Paul L. Gribble ◽

J. Andrew Pruszynski

Keyword(s):

Motor Learning ◽

Muscle Activity ◽

Shoulder Joint ◽

Stretch Reflex ◽

Feedforward Control ◽

Motor Task ◽

Joint Torques ◽

Motor Commands ◽

Shoulder Muscle ◽

Long Latency

AbstractPrevious work has demonstrated that when learning a new motor task, the nervous system modifies feedforward (ie. voluntary) motor commands and that such learning transfers to fast feedback (ie. reflex) responses evoked by mechanical perturbations. Here we show the inverse, that learning new feedback responses transfers to feedforward motor commands. Sixty human participants (34 females) used a robotic exoskeleton and either 1) received short duration mechanical perturbations (20 ms) that created pure elbow rotation or 2) generated self-initiated pure elbow rotations. They did so with the shoulder joint free to rotate (normal arm dynamics) or locked (altered arm dynamics) by the robotic manipulandum. With the shoulder unlocked, the perturbation evoked clear shoulder muscle activity in the long-latency stretch reflex epoch (50-100ms post-perturbation), as required for countering the imposed joint torques, but little muscle activity thereafter in the so-called voluntary response. After locking the shoulder joint, which alters the required joint torques to counter pure elbow rotation, we found a reliable reduction in the long-latency stretch reflex over many trials. This reduction transferred to feedforward control as we observed 1) a reduction in shoulder muscle activity during self-initiated pure elbow rotation trials and 2) kinematic errors (ie. aftereffects) in the direction predicted when failing to compensate for normal arm dynamics, even though participants never practiced self-initiated movements with the shoulder locked. Taken together, our work shows that transfer between feedforward and feedback control is bidirectional, furthering the notion that these processes share common neural circuits that underlie motor learning and transfer.

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Interhemispheric transfer of voluntary motor commands in man

Electroencephalography and Clinical Neurophysiology ◽

10.1016/0013-4694(84)90074-9 ◽

1984 ◽

Vol 57 (5) ◽

pp. 441-447 ◽

Cited By ~ 20

Author(s):

M Schieppati ◽

M Musazzi ◽

A Nardone ◽

G Seveso

Keyword(s):

Interhemispheric Transfer ◽

Voluntary Motor ◽

Motor Commands

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Costs and Rewards of Motor Commands

Biological Learning and Control ◽

10.7551/mitpress/8654.003.0012 ◽

2012 ◽

Keyword(s):

Motor Commands

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Motor Commands for Planar Movements of the Upper Limb: Modeling with Taking into Account Realistic Osteo-Muscular Relations

Neurophysiology ◽

10.1007/s11062-020-09874-1 ◽

2020 ◽

Vol 52 (3) ◽

pp. 222-233

Author(s):

A. V. Gorkovenko ◽

S. S. Strafun ◽

Yu. A. Kulyk ◽

W. Pilewska ◽

M. Zasada ◽

...

Keyword(s):

Upper Limb ◽

Motor Commands

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Neurons in the Nucleus papilio contribute to the control of eye movements during REM sleep

Nature Communications ◽

10.1038/s41467-019-13217-y ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

C. Gutierrez Herrera ◽

F. Girard ◽

A. Bilella ◽

T. C. Gent ◽

D. M. Roccaro-Waldmeyer ◽

...

Keyword(s):

Eye Movements ◽

Rem Sleep ◽

Mammalian Brain ◽

Eye Muscle ◽

Genetic Ablation ◽

Rapid Eye Movements ◽

Motor Commands ◽

Calbindin D28k ◽

Contralateral Eye

AbstractRapid eye movements (REM) are characteristic of the eponymous phase of sleep, yet the underlying motor commands remain an enigma. Here, we identified a cluster of Calbindin-D28K-expressing neurons in the Nucleus papilio (NPCalb), located in the dorsal paragigantocellular nucleus, which are active during REM sleep and project to the three contralateral eye-muscle nuclei. The firing of opto-tagged NPCalb neurons is augmented prior to the onset of eye movements during REM sleep. Optogenetic activation of NPCalb neurons triggers eye movements selectively during REM sleep, while their genetic ablation or optogenetic silencing suppresses them. None of these perturbations led to a change in the duration of REM sleep episodes. Our study provides the first evidence for a brainstem premotor command contributing to the control of eye movements selectively during REM sleep in the mammalian brain.

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Does the nervous system depend on kinesthetic information to control natural limb movements?

Behavioral and Brain Sciences ◽

10.1017/s0140525x0007254x ◽

1992 ◽

Vol 15 (4) ◽

pp. 614-632 ◽

Cited By ~ 164

Author(s):

S. C. Gandevia ◽

David Burke

Keyword(s):

Human Subjects ◽

Experimental Studies ◽

Human Movement ◽

Cutaneous Afferents ◽

Motor Commands ◽

Target Article ◽

Natural Movement ◽

Command Signals ◽

Kinesthetic Information

Abstract This target article draws together two groups of experimental studies on the control of human movement through peripheral feedback and centrally generated signals of motor commands. First, during natural movement, feedback from muscle, joint, and cutaneous afferents changes; in human subjects these changes have reflex and kinesthetic consequences. Recent psychophysical and microneurographic evidence suggests that joint and even cutaneous afferents may have a proprioceptive role. Second, the role of centrally generated motor commands in the control of normal movements and movements following acute and chronic deafferentation is reviewed. There is increasing evidence that subjects can perceive their motor commands under various conditions, but that this is inadequate for normal movement; deficits in motor performance arise when the reliance on proprioceptive feedback is abolished either experimentally or because of pathology. During natural movement, the CNS appears to have access to functionally useful input from a range of peripheral receptors as well as from internally generated command signals. The unanswered questions that remain suggest a number of avenues for further research.

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