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Falgairolle M, O'Donovan MJ. Motoneuronal Spinal Circuits in Degenerative Motoneuron Disease. Front Mol Neurosci 2020; 13:74. [PMID: 32523513 PMCID: PMC7261878 DOI: 10.3389/fnmol.2020.00074] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 04/15/2020] [Indexed: 12/22/2022] Open
Abstract
The most evident phenotype of degenerative motoneuron disease is the loss of motor function which accompanies motoneuron death. In both amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), it is now clear that dysfunction is not restricted to motoneurons but is manifest in the spinal circuits in which motoneurons are embedded. As mounting evidence shows that motoneurons possess more elaborate and extensive connections within the spinal cord than previously realized, it is necessary to consider the role of this circuitry and its dysfunction in the disease process. In this review article, we ask if the selective vulnerability of the different motoneuron types and the relative disease resistance of distinct motoneuron groups can be understood in terms of their intraspinal connections.
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Affiliation(s)
- Mélanie Falgairolle
- Section on Developmental Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Michael J O'Donovan
- Section on Developmental Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
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Niwa M, Muramatsu K, Nakayama K, Sasaki SI. Electrophysiological properties of Ia excitation and recurrent inhibition in cat abdominal motoneurons. J Physiol Sci 2019; 69:253-262. [PMID: 30324557 PMCID: PMC10716931 DOI: 10.1007/s12576-018-0643-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 09/28/2018] [Indexed: 11/29/2022]
Abstract
Ia excitation and recurrent inhibition are basic neuronal circuits in motor control in hind limb. Renshaw cells receive synaptic inputs from axon collaterals of motoneurons and inhibit motoneurons and Ia inhibitory interneurons. It is important to know properties of Ia excitation and recurrent inhibition of trunk muscle such as abdominal muscles. The abdominal muscles have many roles and change those roles for different kind of functions. Intracellular recordings were obtained from the abdominal motoneurons of the upper lumbar segments in cats anesthetized. First, dorsal roots were left intact, and sensory and motor axons were electrically stimulated. Ia excitatory post-synaptic potentials were elicited in five of eight motoneurons at same segment stimulated. Second, dorsal roots were sectioned, and motor axons were electrically stimulated. Recurrent inhibitory post-synaptic potentials were elicited in one of 11 abdominal motoneurons. Renshaw cells extracellularly fired high-frequency bursts at short latency and at same segment stimulated.
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Affiliation(s)
- Masatoshi Niwa
- Department of Occupational Therapy, Kyorin University, 5-4-1 Shimorenjaku, Mitaka, Tokyo, 181-8612, Japan.
| | - Ken Muramatsu
- Department of Physical Therapy, Health Science University, 7187 Kodachi, Fujikawaguchiko, Yamanashi, 401-0380, Japan
| | - Kiyomi Nakayama
- Department of Oral Physiology, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo, 142-8555, Japan
| | - Sei-Ichi Sasaki
- Center for Medical Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki, Ibaraki, 300-0394, Japan
- Tokyo Public Health College, 6-21-7 Hommachi, Shibuya-ku, Tokyo, 151-0071, Japan
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Brownstone RM, Lancelin C. Escape from homeostasis: spinal microcircuits and progression of amyotrophic lateral sclerosis. J Neurophysiol 2018; 119:1782-1794. [PMID: 29384454 PMCID: PMC6008087 DOI: 10.1152/jn.00331.2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In amyotrophic lateral sclerosis (ALS), loss of motoneuron function leads to weakness and, ultimately, respiratory failure and death. Regardless of the initial pathogenic factors, motoneuron loss follows a specific pattern: the largest α-motoneurons die before smaller α-motoneurons, and γ-motoneurons are spared. In this article, we examine how homeostatic responses to this orderly progression could lead to local microcircuit dysfunction that in turn propagates motoneuron dysfunction and death. We first review motoneuron diversity and the principle of α-γ coactivation and then discuss two specific spinal motoneuron microcircuits: those involving proprioceptive afferents and those involving Renshaw cells. Next, we propose that the overall homeostatic response of the nervous system is aimed at maintaining force output. Thus motoneuron degeneration would lead to an increase in inputs to motoneurons, and, because of the pattern of neuronal degeneration, would result in an imbalance in local microcircuit activity that would overwhelm initial homeostatic responses. We suggest that this activity would ultimately lead to excitotoxicity of motoneurons, which would hasten the progression of disease. Finally, we propose that should this be the case, new therapies targeted toward microcircuit dysfunction could slow the course of ALS.
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Affiliation(s)
- Robert M Brownstone
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London , London , United Kingdom
| | - Camille Lancelin
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London , London , United Kingdom
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Sweeney LB, Bikoff JB, Gabitto MI, Brenner-Morton S, Baek M, Yang JH, Tabak EG, Dasen JS, Kintner CR, Jessell TM. Origin and Segmental Diversity of Spinal Inhibitory Interneurons. Neuron 2018; 97:341-355.e3. [PMID: 29307712 PMCID: PMC5880537 DOI: 10.1016/j.neuron.2017.12.029] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 11/14/2017] [Accepted: 12/17/2017] [Indexed: 10/18/2022]
Abstract
Motor output varies along the rostro-caudal axis of the tetrapod spinal cord. At limb levels, ∼60 motor pools control the alternation of flexor and extensor muscles about each joint, whereas at thoracic levels as few as 10 motor pools supply muscle groups that support posture, inspiration, and expiration. Whether such differences in motor neuron identity and muscle number are associated with segmental distinctions in interneuron diversity has not been resolved. We show that select combinations of nineteen transcription factors that specify lumbar V1 inhibitory interneurons generate subpopulations enriched at limb and thoracic levels. Specification of limb and thoracic V1 interneurons involves the Hox gene Hoxc9 independently of motor neurons. Thus, early Hox patterning of the spinal cord determines the identity of V1 interneurons and motor neurons. These studies reveal a developmental program of V1 interneuron diversity, providing insight into the organization of inhibitory interneurons associated with differential motor output.
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Affiliation(s)
- Lora B Sweeney
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
| | - Jay B Bikoff
- Howard Hughes Medical Institute, Zuckerman Institute, Departments of Neuroscience, and Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Mariano I Gabitto
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, NY 10010, USA.
| | - Susan Brenner-Morton
- Howard Hughes Medical Institute, Zuckerman Institute, Departments of Neuroscience, and Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Myungin Baek
- Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA
| | - Jerry H Yang
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Esteban G Tabak
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012, USA
| | - Jeremy S Dasen
- Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA
| | - Christopher R Kintner
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Thomas M Jessell
- Howard Hughes Medical Institute, Zuckerman Institute, Departments of Neuroscience, and Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA.
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Goetz C, Pivetta C, Arber S. Distinct limb and trunk premotor circuits establish laterality in the spinal cord. Neuron 2014; 85:131-144. [PMID: 25543457 DOI: 10.1016/j.neuron.2014.11.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2014] [Indexed: 12/31/2022]
Abstract
Movement coordination between opposite body sides relies on neuronal circuits capable of controlling muscle contractions according to motor commands. Trunk and limb muscles engage in distinctly lateralized behaviors, yet how regulatory spinal circuitry differs is less clear. Here, we intersect virus technology and mouse genetics to unravel striking distribution differences of interneurons connected to functionally distinct motor neurons. We find that premotor interneurons conveying information to axial motor neurons reside in symmetrically balanced locations while mostly ipsilateral premotor interneurons synapse with limb-innervating motor neurons, especially those innervating more distal muscles. We show that observed distribution differences reflect specific premotor interneuron subpopulations defined by genetic and neurotransmitter identity. Synaptic input across the midline reaches axial motor neurons preferentially through commissural axon arborization, and to a lesser extent, through midline-crossing dendrites capturing contralateral synaptic input. Together, our findings provide insight into principles of circuit organization underlying weighted lateralization of movement.
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Affiliation(s)
- Cyrill Goetz
- Biozentrum, Department of Cell Biology, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland; Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Chiara Pivetta
- Biozentrum, Department of Cell Biology, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland; Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Silvia Arber
- Biozentrum, Department of Cell Biology, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland; Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.
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Ford TW, Meehan CF, Kirkwood PA. Absence of synergy for monosynaptic Group I inputs between abdominal and internal intercostal motoneurons. J Neurophysiol 2014; 112:1159-68. [PMID: 24920027 PMCID: PMC4122728 DOI: 10.1152/jn.00245.2014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Internal intercostal and abdominal motoneurons are strongly coactivated during expiration. We investigated whether that synergy was paralleled by synergistic Group I reflex excitation. Intracellular recordings were made from motoneurons of the internal intercostal nerve of T8 in anesthetized cats, and the specificity of the monosynaptic connections from afferents in each of the two main branches of this nerve was investigated. Motoneurons were shown by antidromic excitation to innervate three muscle groups: external abdominal oblique [EO; innervated by the lateral branch (Lat)], the region of the internal intercostal muscle proximal to the branch point (IIm), and muscles innervated from the distal remainder (Dist). Strong specificity was observed, only 2 of 54 motoneurons showing excitatory postsynaptic potentials (EPSPs) from both Lat and Dist. No EO motoneurons showed an EPSP from Dist, and no IIm motoneurons showed one from Lat. Expiratory Dist motoneurons fell into two groups. Those with Dist EPSPs and none from Lat (group A) were assumed to innervate distal internal intercostal muscle. Those with Lat EPSPs (group B) were assumed to innervate abdominal muscle (transversus abdominis or rectus abdominis). Inspiratory Dist motoneurons (assumed to innervate interchondral muscle) showed Dist EPSPs. Stimulation of dorsal ramus nerves gave EPSPs in 12 instances, 9 being in group B Dist motoneurons. The complete absence of heteronymous monosynaptic Group I reflex excitation between muscles that are synergistically activated in expiration leads us to conclude that such connections from muscle spindle afferents of the thoracic nerves have little role in controlling expiratory movements but, where present, support other motor acts.
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Affiliation(s)
- T W Ford
- University of Nottingham School of Health Sciences, Queen's Medical Centre, Nottingham, United Kingdom; and
| | - C F Meehan
- Department of Neuroscience and Pharmacology, Panum Institute, Copenhagen N, Denmark
| | - P A Kirkwood
- Sobell Department for Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, London, United Kingdom;
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de Nooij JC, Doobar S, Jessell TM. Etv1 inactivation reveals proprioceptor subclasses that reflect the level of NT3 expression in muscle targets. Neuron 2013; 77:1055-68. [PMID: 23522042 DOI: 10.1016/j.neuron.2013.01.015] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/02/2013] [Indexed: 01/12/2023]
Abstract
The organization of spinal reflex circuits relies on the specification of distinct classes of proprioceptive sensory neurons (pSN), but the factors that drive such diversity remain unclear. We report here that pSNs supplying distinct skeletal muscles differ in their dependence on the ETS transcription factor Etv1 for their survival and differentiation. The status of Etv1-dependence is linked to the location of proprioceptor muscle targets: pSNs innervating hypaxial and axial muscles depend critically on Etv1 for survival, whereas those innervating certain limb muscles are resistant to Etv1 inactivation. The level of NT3 expression in individual muscles correlates with Etv1-dependence and the loss of pSNs triggered by Etv1 inactivation can be prevented by elevating the level of muscle-derived NT3-revealing a TrkC-activated Etv1-bypass pathway. Our findings support a model in which the specification of aspects of pSN subtype character is controlled by variation in the level of muscle NT3 expression and signaling.
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Affiliation(s)
- Joriene C de Nooij
- Department of Neuroscience, Howard Hughes Medical Institute, Kavli Institute for Brain Science, Columbia University, New York, NY 10032, USA
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Saywell SA, Ford TW, Meehan CF, Todd AJ, Kirkwood PA. Electrophysiological and morphological characterization of propriospinal interneurons in the thoracic spinal cord. J Neurophysiol 2011; 105:806-26. [PMID: 21106900 PMCID: PMC3059177 DOI: 10.1152/jn.00738.2010] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 11/18/2010] [Indexed: 12/29/2022] Open
Abstract
Propriospinal interneurons in the thoracic spinal cord have vital roles not only in controlling respiratory and trunk muscles, but also in providing possible substrates for recovery from spinal cord injury. Intracellular recordings were made from such interneurons in anesthetized cats under neuromuscular blockade and with the respiratory drive stimulated by inhaled CO(2). The majority of the interneurons were shown by antidromic activation to have axons descending for at least two to four segments, mostly contralateral to the soma. In all, 81% of the neurons showed postsynaptic potentials (PSPs) to stimulation of intercostal or dorsal ramus nerves of the same segment for low-threshold (≤ 5T) afferents. A monosynaptic component was present for the majority of the peripherally evoked excitatory PSPs. A central respiratory drive potential was present in most of the recordings, usually of small amplitude. Neurons depolarized in either inspiration or expiration, sometimes variably. The morphology of 17 of the interneurons and/or of their axons was studied following intracellular injection of Neurobiotin; 14 axons were descending, 6 with an additional ascending branch, and 3 were ascending (perhaps actually representing ascending tract cells); 15 axons were crossed, 2 ipsilateral, none bilateral. Collaterals were identified for 13 axons, showing exclusively unilateral projections. The collaterals were widely spaced and their terminations showed a variety of restricted locations in the ventral horn or intermediate area. Despite heterogeneity in detail, both physiological and morphological, which suggests heterogeneity of function, the projections mostly fitted a consistent general pattern: crossed axons, with locally weak, but widely distributed terminations.
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Affiliation(s)
- S A Saywell
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
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Evolutionary psychologists need to distinguish between the evolutionary process, ancestral selection pressures, and psychological mechanisms. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025577] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Selfishness reexamined: No man is an island. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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How useful is a concept such as muscle partitioning? Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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The physiological basis and implications of differential motor activation. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Selfish genes and ingroup altruism. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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A Comparative approach to muscle function. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x0002505x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
AbstractSocial dilemmas occur when the pursuit of self-interest by individuals in a group leads to less than optimal collective outcomes for everyone in the group. A critical assumption in the human sciences is that people's choices in such dilemmas are individualistic, selfish, and rational. Hence, cooperation in the support of group welfare will only occur if there are selfish incentives that convert the social dilemma into a nondilemma. In recent years, inclusive fitness theories have lent weight to such traditional views of rational selfishness on Darwinian grounds. To show that cooperation is based on selfish incentives, however, one must provide evidence that people do not cooperate without such incentives. In a series of experimental social dilemmas, subjects were instructed to make single, anonymous choices about whether or not to contribute money for a shared “bonus” that would be provided only if enough other people in the group also contributed their money. Noncontributors cited selfish reasons for their choices; contributors did not. If people are allowed to engage in discussion, they will contribute resources at high rates, frequently on irrational grounds, to promote group welfare. These findings are consistent with previous research on ingroup biasing effects that cannot be explained by “economic man” or “selfish gene” theories. An alternative explanation is that sociality was a primary factor shaping the evolution of Homo sapiens. The cognitive and affective mechanisms underlying such choices evolved under selection pressures on small groups for developing and maintaining group membership and for predicting and controlling the behavior of other group members. This sociality hypothesis organizes previously inexplicable and disparate phenomena in a Darwinian framework and makes novel predictions about human choice.
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Continuous and discrete models and measures of speech events. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Partitioning hypothesis in perspective. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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A multiple source, or, is a striped apple more striped than a striped orange? Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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The use of mathematical models in perceptual theory. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Ecological and social factors in hominid evolution. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Central partitioning may be altered during high-frequency activation of the lamotoneuron connection. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Speech perception by ear, eye, hand, and mind. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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What is the organization, scope, and functional significance of partitioning? Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
AbstractStudies have shown that in the mammalian neuromuscular system stretch reflexes are localized within individual muscles. Neuromuscular compartmentalization, the partitioning of sensory output from muscles, and the partitioning of segmental pathways to motor nuclei have also been demonstrated. This evidence indicates that individual motor nuclei and the muscles they innervate are not homogeneous functional units. An analysis of the functional significance of reflex localization and partitioning suggests that segmental control mechanisms are based on subdivisions of motor nuclei–muscle complexes. A partitioned organization of segmental control mechanisms could utilize (1) the potential functional diversity of muscle fiber types, (2) the variety of mechanical actions of individual muscles arising from their distributed origins and insertions, and (3) diverse architectural features such as intramuscular variations in pinnation and complex in-series and in-parallel arrangements of muscle fibers. The differentiated activity observed in some muscles during natural movements also calls for localized segmental control mechanisms. Partitioning may also play a role in mechanical interactions between contracting motor units and in increasing the stability of neuromuscular systems. The functional advantages of reflex localization and partitioning suggest they are probably common features of segmental systems, whose organization reflects the structure and function of their associated neuromuscular systems.
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Do we need two souls to explain cooperation? Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Acoustic reflex partitioning in the stapedius. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Reflex partitioning and differential control of human motor units. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x00025231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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On the regional distribution of muscle spindles. Behav Brain Sci 2010. [DOI: 10.1017/s0140525x0002522x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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