The Experts below are selected from a list of 1413 Experts worldwide ranked by ideXlab platform
Martyn Goulding - One of the best experts on this subject based on the ideXlab platform.
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CorticoSpinal Circuits from the Sensory and Motor Cortices Differentially Regulate Skilled Movements through Distinct Spinal Interneurons
Elsevier, 2018Co-Authors: Masaki Ueno, Martyn Goulding, Yuka Nakamura, Jesse Niehaus, Mari Maezawa, Steven A. Crone, Mark L. Baccei, Yutaka YoshidaAbstract:Summary: Little is known about the organizational and functional connectivity of the corticoSpinal (CS) circuits that are essential for voluntary movement. Here, we map the connectivity between CS neurons in the forelimb motor and sensory cortices and various Spinal Interneurons, demonstrating that distinct CS-Interneuron circuits control specific aspects of skilled movements. CS fibers originating in the mouse motor cortex directly synapse onto premotor Interneurons, including those expressing Chx10. Lesions of the motor cortex or silencing of Spinal Chx10+ Interneurons produces deficits in skilled reaching. In contrast, CS neurons in the sensory cortex do not synapse directly onto premotor Interneurons, and they preferentially connect to Vglut3+ Spinal Interneurons. Lesions to the sensory cortex or inhibition of Vglut3+ Interneurons cause deficits in food pellet release movements in goal-oriented tasks. These findings reveal that CS neurons in the motor and sensory cortices differentially control skilled movements through distinct CS-Spinal Interneuron circuits. : Ueno et al. generate a detailed connectivity map between corticoSpinal (CS) neurons in the motor and sensory cortices and Spinal Interneurons. The CS circuits originating from the motor and sensory cortices connect to distinct subpopulations of Spinal Interneurons to control discrete aspects of skilled movements. Keywords: corticoSpinal neuron, Spinal Interneuron, motor neuron, motor cortex, sensory cortex, skilled movement, Chx10, V2a, Vglut
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renshaw cell Interneuron specialization is controlled by a temporally restricted transcription factor program
Development, 2012Co-Authors: Floor J Stam, Eric J Geiman, Timothy J Hendricks, Cedric Francius, Frédéric Clotman, Jingming Zhang, Patricia A Labosky, Martyn GouldingAbstract:The Spinal cord contains a diverse array of physiologically distinct Interneuron cell types that subserve specialized roles in somatosensory perception and motor control. The mechanisms that generate these specialized Interneuronal cell types from multipotential Spinal progenitors are not known. In this study, we describe a temporally regulated transcriptional program that controls the differentiation of Renshaw cells (RCs), an anatomically and functionally discrete Spinal Interneuron subtype. We show that the selective activation of the Onecut transcription factors Oc1 and Oc2 during the first wave of V1 Interneuron neurogenesis is a key step in the RC differentiation program. The development of RCs is additionally dependent on the forkhead transcription factor Foxd3, which is more broadly expressed in postmitotic V1 Interneurons. Our demonstration that RCs are born, and activate Oc1 and Oc2 expression, in a narrow temporal window leads us to posit that neuronal diversity in the developing Spinal cord is established by the composite actions of early spatial and temporal determinants.
Robert E.w. Fyffe - One of the best experts on this subject based on the ideXlab platform.
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the continuing case for the renshaw cell
The Journal of Physiology, 2007Co-Authors: Francisco J Alvarez, Robert E.w. FyffeAbstract:Renshaw cell properties have been studied extensively for over 50 years, making them a uniquely well-defined class of Spinal Interneuron. Recent work has revealed novel ways to identify Renshaw cells in situ and this in turn has promoted a range of studies that have determined their ontogeny and organization of synaptic inputs in unprecedented detail. In this review we illustrate how mature Renshaw cell properties and connectivity arise through a combination of activity-dependent and genetically specified mechanisms. These new insights should aid the development of experimental strategies to manipulate Renshaw cells in Spinal circuits and clarify their role in modulating motor output.
Thomas M Jessell - One of the best experts on this subject based on the ideXlab platform.
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Degradation of mouse locomotor pattern in the absence of proprioceptive sensory feedback
Proceedings of the National Academy of Sciences of the United States of America, 2014Co-Authors: Turgay Akay, Silvia Arber, Warren G. Tourtellotte, Thomas M JessellAbstract:Mammalian locomotor programs are thought to be directed by the actions of Spinal Interneuron circuits collectively referred to as “central pattern generators.” The contribution of proprioceptive sensory feedback to the coordination of locomotor activity remains less clear. We have analyzed changes in mouse locomotor pattern under conditions in which proprioceptive feedback is attenuated genetically and biomechanically. We find that locomotor pattern degrades upon elimination of proprioceptive feedback from muscle spindles and Golgi tendon organs. The degradation of locomotor pattern is manifest as the loss of interjoint coordination and alternation of flexor and extensor muscles. Group Ia/II sensory feedback from muscle spindles has a predominant influence in patterning the activity of flexor muscles, whereas the redundant activities of group Ia/II and group Ib afferents appear to determine the pattern of extensor muscle firing. These findings establish a role for proprioceptive feedback in the control of fundamental aspects of mammalian locomotor behavior.
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neuronal ig caspr recognition promotes the formation of axoaxonic synapses in mouse Spinal cord
Neuron, 2014Co-Authors: Soha Ashrafi, Nicholas J Betley, John D Comer, Susan Brennermorton, Yasushi Shimoda, Kazutada Watanabe, Elior Peles, Thomas M JessellAbstract:Inhibitory microcircuits are wired with a precision that underlies their complex regulatory roles in neural information processing. In the Spinal cord, one specialized class of GABAergic Interneurons (GABApre) mediates presynaptic inhibitory control of sensory-motor synapses. The synaptic targeting of these GABAergic neurons exhibits an absolute dependence on proprioceptive sensory terminals, yet the molecular underpinnings of this specialized axoaxonic organization remain unclear. Here, we show that sensory expression of an NB2 (Contactin5)/Caspr4 coreceptor complex, together with Spinal Interneuron expression of NrCAM/CHL1, directs the high-density accumulation of GABAergic boutons on sensory terminals. Moreover, genetic elimination of NB2 results in a disproportionate stripping of inhibitory boutons from high-density GABApre-sensory synapses, suggesting that the preterminal axons of GABApre neurons compete for access to individual sensory terminals. Our findings define a recognition complex that contributes to the assembly and organization of a specialized GABAergic microcircuit.
Robert R Young - One of the best experts on this subject based on the ideXlab platform.
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recurrent inhibition is increased in patients with Spinal cord injury
Neurology, 1992Co-Authors: Jeremy M Shefner, Stephen A Berman, Mehdi Sarkarati, Robert R YoungAbstract:Mechanisms underlying the development of spasticity after Spinal cord injury are not understood. One Spinal Interneuron likely to be affected is the Renshaw cell, which acts to produce recurrent inhibition in motor neurons as well as inhibiting Ia Interneurons. Descending pathways exert both excitatory and inhibitory control over Renshaw cell activity. We studied Renshaw cell activity in normal subjects and in patients with varying levels of spasticity after Spinal cord injury using the conditioned H-reflex technique of Pierrot-Deseilligny and Bussel. A submaximal stimulus to the tibial nerve is presented prior to a supramaximal stimulus so that action potential collision permits an H reflex (H9) to be elicited in response to the supramaximal stimulus. The amplitude of this H9 reflex is affected by activity in recurrent inhibitory pathways. Patients with both complete and partial Spinal cord lesions were studied; date of injury ranged from 1 month to 216 months prior to evaluation. In the 18 patients in whom H reflexes could be recorded, H9 reflexes were absent in 13, in contrast to their uniform presence in normal subjects. We conclude that recurrent inhibition via Renshaw cell activity is increased in Spinal cord injury, and that measures of recurrent inhibition may correlate well with some clinical measures of spasticity.
Francisco J Alvarez - One of the best experts on this subject based on the ideXlab platform.
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the continuing case for the renshaw cell
The Journal of Physiology, 2007Co-Authors: Francisco J Alvarez, Robert E.w. FyffeAbstract:Renshaw cell properties have been studied extensively for over 50 years, making them a uniquely well-defined class of Spinal Interneuron. Recent work has revealed novel ways to identify Renshaw cells in situ and this in turn has promoted a range of studies that have determined their ontogeny and organization of synaptic inputs in unprecedented detail. In this review we illustrate how mature Renshaw cell properties and connectivity arise through a combination of activity-dependent and genetically specified mechanisms. These new insights should aid the development of experimental strategies to manipulate Renshaw cells in Spinal circuits and clarify their role in modulating motor output.
