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Cohen JW, Vieira TM, Ivanova TD, Garland SJ. Differential behavior of distinct motoneuron pools that innervate the triceps surae. J Neurophysiol 2023; 129:272-284. [PMID: 36475977 DOI: 10.1152/jn.00336.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
It has been shown that when humans lean in various directions, the central nervous system (CNS) recruits different motoneuron pools for task completion; common units that are active during different leaning directions, and unique units that are active in only one leaning direction. We used high-density surface electromyography (HD-sEMG) to examine if motor unit (MU) firing behavior was dependent on leaning direction, muscle (medial and lateral gastrocnemius; soleus), limits of stability, or whether a MU is considered common or unique. Fourteen healthy participants stood on a force platform and maintained their center of pressure in five different leaning directions. HD-sEMG recordings were decomposed into MU action potentials and the average firing rate (AFR), coefficient of variation (CoVISI), and firing intermittency were calculated on the MU spike trains. During the 30°-90° leaning directions both unique units and common units had higher firing rates (F = 31.31, P < 0.0001). However, the unique units achieved higher firing rates compared with the common units (mean estimate difference = 3.48 Hz, P < 0.0001). The CoVISI increased across directions for the unique units but not for the common units (F = 23.65, P < 0.0001). Finally, intermittent activation of MUs was dependent on the leaning direction (F = 11.15, P < 0.0001), with less intermittent activity occurring during diagonal and forward-leaning directions. These results provide evidence that the CNS can preferentially control separate motoneuron pools within the ankle plantarflexors during voluntary leaning tasks for the maintenance of standing balance.NEW & NOTEWORTHY In this study, we demonstrate that the different subpopulations of motor units within the three muscles comprising the ankle plantarflexors behave differently during multidirectional leaning. Our results suggest that the central nervous system has the capability to control distinct subpopulations of motor units to meet the force requirements necessary for leaning. This may allow for a precise, efficient, and flexible control strategy for the maintenance of standing balance.
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Affiliation(s)
- Joshua W Cohen
- School of Kinesiology, Western University, London, Ontario, Canada.,Collaborative Specialization in Musculoskeletal Health Research, Bone and Joint Institute, Western University, London, Ontario, Canada
| | - Taian M Vieira
- Laboratorio di Ingegneria del Sistema Neuromuscolare (LISiN), Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, Turin, Italy
| | - Tanya D Ivanova
- Physical Therapy, Faculty of Health Sciences, Western University, London, Ontario, Canada
| | - S Jayne Garland
- Physical Therapy, Faculty of Health Sciences, Western University, London, Ontario, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
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Marshall NJ, Glaser JI, Trautmann EM, Amematsro EA, Perkins SM, Shadlen MN, Abbott LF, Cunningham JP, Churchland MM. Flexible neural control of motor units. Nat Neurosci 2022; 25:1492-1504. [PMID: 36216998 PMCID: PMC9633430 DOI: 10.1038/s41593-022-01165-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 08/12/2022] [Indexed: 01/13/2023]
Abstract
Voluntary movement requires communication from cortex to the spinal cord, where a dedicated pool of motor units (MUs) activates each muscle. The canonical description of MU function rests upon two foundational tenets. First, cortex cannot control MUs independently but supplies each pool with a common drive. Second, MUs are recruited in a rigid fashion that largely accords with Henneman's size principle. Although this paradigm has considerable empirical support, a direct test requires simultaneous observations of many MUs across diverse force profiles. In this study, we developed an isometric task that allowed stable MU recordings, in a rhesus macaque, even during rapidly changing forces. Patterns of MU activity were surprisingly behavior-dependent and could be accurately described only by assuming multiple drives. Consistent with flexible descending control, microstimulation of neighboring cortical sites recruited different MUs. Furthermore, the cortical population response displayed sufficient degrees of freedom to potentially exert fine-grained control. Thus, MU activity is flexibly controlled to meet task demands, and cortex may contribute to this ability.
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Affiliation(s)
- Najja J Marshall
- Department of Neuroscience, Columbia University Medical Center, New York, NY, USA
- Zuckerman Institute, Columbia University, New York, NY, USA
| | - Joshua I Glaser
- Zuckerman Institute, Columbia University, New York, NY, USA
- Department of Statistics, Columbia University, New York, NY, USA
- Grossman Center for the Statistics of Mind, Columbia University, New York, NY, USA
- Center for Theoretical Neuroscience, Columbia University Medical Center, New York, NY, USA
| | - Eric M Trautmann
- Department of Neuroscience, Columbia University Medical Center, New York, NY, USA
- Zuckerman Institute, Columbia University, New York, NY, USA
- Grossman Center for the Statistics of Mind, Columbia University, New York, NY, USA
| | - Elom A Amematsro
- Department of Neuroscience, Columbia University Medical Center, New York, NY, USA
- Zuckerman Institute, Columbia University, New York, NY, USA
| | - Sean M Perkins
- Zuckerman Institute, Columbia University, New York, NY, USA
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Michael N Shadlen
- Department of Neuroscience, Columbia University Medical Center, New York, NY, USA
- Zuckerman Institute, Columbia University, New York, NY, USA
- Kavli Institute for Brain Science, Columbia University Medical Center, New York, NY, USA
- Howard Hughes Medical Institute, Columbia University, New York, NY, USA
| | - L F Abbott
- Department of Neuroscience, Columbia University Medical Center, New York, NY, USA
- Zuckerman Institute, Columbia University, New York, NY, USA
- Center for Theoretical Neuroscience, Columbia University Medical Center, New York, NY, USA
- Kavli Institute for Brain Science, Columbia University Medical Center, New York, NY, USA
- Department of Physiology and Cellular Biophysics, Columbia University Medical Center, New York, NY, USA
| | - John P Cunningham
- Zuckerman Institute, Columbia University, New York, NY, USA
- Department of Statistics, Columbia University, New York, NY, USA
- Grossman Center for the Statistics of Mind, Columbia University, New York, NY, USA
- Center for Theoretical Neuroscience, Columbia University Medical Center, New York, NY, USA
| | - Mark M Churchland
- Department of Neuroscience, Columbia University Medical Center, New York, NY, USA.
- Zuckerman Institute, Columbia University, New York, NY, USA.
- Grossman Center for the Statistics of Mind, Columbia University, New York, NY, USA.
- Kavli Institute for Brain Science, Columbia University Medical Center, New York, NY, USA.
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Bräcklein M, Barsakcioglu DY, Ibáñez J, Eden J, Burdet E, Mehring C, Farina D. The control and training of single motor units in isometric tasks are constrained by a common input signal. eLife 2022; 11:72871. [PMID: 35670561 PMCID: PMC9208758 DOI: 10.7554/elife.72871] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 06/06/2022] [Indexed: 11/15/2022] Open
Abstract
Recent developments in neural interfaces enable the real-time and non-invasive tracking of motor neuron spiking activity. Such novel interfaces could provide a promising basis for human motor augmentation by extracting potentially high-dimensional control signals directly from the human nervous system. However, it is unclear how flexibly humans can control the activity of individual motor neurons to effectively increase the number of degrees of freedom available to coordinate multiple effectors simultaneously. Here, we provided human subjects (N = 7) with real-time feedback on the discharge patterns of pairs of motor units (MUs) innervating a single muscle (tibialis anterior) and encouraged them to independently control the MUs by tracking targets in a 2D space. Subjects learned control strategies to achieve the target-tracking task for various combinations of MUs. These strategies rarely corresponded to a volitional control of independent input signals to individual MUs during the onset of neural activity. Conversely, MU activation was consistent with a common input to the MU pair, while individual activation of the MUs in the pair was predominantly achieved by alterations in de-recruitment order that could be explained by history-dependent changes in motor neuron excitability. These results suggest that flexible MU recruitment based on independent synaptic inputs to single MUs is unlikely, although de-recruitment might reflect varying inputs or modulations in the neuron’s intrinsic excitability.
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Affiliation(s)
| | | | - Jaime Ibáñez
- Department of Bioengineering, Imperial College London
| | - Jonathan Eden
- Department of Bioengineering, Imperial College London
| | | | | | - Dario Farina
- Department of Bioengineering, Imperial College London
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Lei Y, Suresh NL, Rymer WZ, Hu X. Organization of the motor-unit pool for different directions of isometric contraction of the first dorsal interosseous muscle. Muscle Nerve 2017; 57:E85-E93. [PMID: 28877550 DOI: 10.1002/mus.25963] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2017] [Indexed: 11/08/2022]
Abstract
INTRODUCTION Muscle force generation involves recruitment and firing rate modulation of motor units (MUs). The control of MUs in producing multidirectional forces remains unclear. METHODS We studied MU recruitment and firing properties, recorded from the first dorsal interosseous muscle, for 3 different directions of contraction: abduction; abduction/flexion combination; and flexion. RESULTS MUs were recruited systematically at higher threshold force during flexion. Larger MUs were recruited and firing rates of MUs were lower during abduction. There was an orderly recruitment of MUs according to MU size regardless of contraction direction, obeying the "size principle." Firing rates of earlier-recruited MUs were consistently higher than later-recruited MUs, affirming the "onion-skin" property. DISCUSSION Our findings suggest that the size principle and onion-skin organization together provide a general description of MU recruitment patterns and firing properties. The directional alternations of MU control properties likely reflect changes in neural drive to the muscle. Muscle Nerve 57: E85-E93, 2018.
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Affiliation(s)
- Yuming Lei
- The Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami, 1095 NW 14th Terrace #48, Miami, Florida 33136, USA
| | - Nina L Suresh
- Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, Illinois, USA
| | - William Z Rymer
- Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, Illinois, USA
| | - Xiaogang Hu
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, North Carolina, USA
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Tucker K, Hodges PW, Van den Hoorn W, Nordez A, Hug F. Does stress within a muscle change in response to an acute noxious stimulus? PLoS One 2014; 9:e91899. [PMID: 24626150 PMCID: PMC3953640 DOI: 10.1371/journal.pone.0091899] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 02/11/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Altered muscle activation during pain is thought to redistribute stress within muscles and ultimately decrease the load on painful structures. However, change in muscle stress during pain has not been directly tested. The aim of the present study is to determine whether stress within muscle tissue is reduced during local acute experimental pain. METHODS AND RESULTS Ten participants attended 2 experimental sessions that each involved isometric knee extension tasks in 2 series of control trials and 1 series of test trials at ∼10%MVC. Shear elastic modulus was measured from vastus lateralis using a shear wave elastographic technique (Supersonic Shear Imaging). Prior to the test contractions, a bolus of hypertonic (Pain) or isotonic saline (No-pain) was injected into vastus lateralis. Pain intensity was 5.2±1.0 during the painful contractions. The intra-session repeatability of the shear elastic modulus determined between control trials was good (ICC: 0.95 and 0.99; SEM: 5.1 and 9.3 kPa for No-pain and Pain, respectively). Muscle shear elastic modulus did not change systematically during Pain or No-pain contractions (all main effects and interaction P>0.14). Examination of data for individual participants showed that stress either increased or decreased. If the absolute change in modulus is considered between the control and the test trials, the change during Pain (16.2±9.5 kPa) was double that observed with No pain (7.9±5.9 kPa; P = 0.046). CONCLUSION This is the first study to directly determine the change in stress within a muscle (change in shear elastic modulus) during pain. We conclude that experimental pain induced by hypertonic saline does not induce a systematic reduction in muscle stress during a single-joint isometric task. Therefore, the changes in muscle activity reported previously during similar tasks are unlikely to systematically reduce load in the painful region. Whether the individual-specific increase and decrease are physiologically relevant or purposeful requires further investigation.
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Affiliation(s)
- Kylie Tucker
- School of Health and Rehabilitation Sciences, National Health and Medical Research Council (NHMRC) Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, The University of Queensland, Brisbane, Queensland, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Paul W. Hodges
- School of Health and Rehabilitation Sciences, National Health and Medical Research Council (NHMRC) Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, The University of Queensland, Brisbane, Queensland, Australia
| | - Wolbert Van den Hoorn
- School of Health and Rehabilitation Sciences, National Health and Medical Research Council (NHMRC) Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, The University of Queensland, Brisbane, Queensland, Australia
| | - Antoine Nordez
- University of Nantes, Laboratory “Motricité, Interactions, Performance” (EA 4334), Nantes, France
| | - François Hug
- School of Health and Rehabilitation Sciences, National Health and Medical Research Council (NHMRC) Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, The University of Queensland, Brisbane, Queensland, Australia
- University of Nantes, Laboratory “Motricité, Interactions, Performance” (EA 4334), Nantes, France
- * E-mail:
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Tucker KJ, Hodges PW. Changes in motor unit recruitment strategy during pain alters force direction. Eur J Pain 2012; 14:932-8. [DOI: 10.1016/j.ejpain.2010.03.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Revised: 02/22/2010] [Accepted: 03/13/2010] [Indexed: 10/19/2022]
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Similar alteration of motor unit recruitment strategies during the anticipation and experience of pain. Pain 2011; 153:636-643. [PMID: 22209423 DOI: 10.1016/j.pain.2011.11.024] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 11/20/2011] [Accepted: 11/22/2011] [Indexed: 11/20/2022]
Abstract
A motor unit consists of a motoneurone and the multiple muscle fibres that it innervates, and forms the final neural pathway that influences movement. Discharge of motor units is altered (decreased discharge rate and/or cessation of firing; and increased discharge rate and/or recruitment of new units) during matched-force contractions with pain. This is thought to be mediated by nociceptive (pain) input on motoneurones, as demonstrated in animal studies. It is also possible that motoneurone excitability is altered by pain related descending inputs, that these changes persist after noxious stimuli cease, and that direct nociceptive input is not necessary to induce pain related changes in movement. We aimed to determine whether anticipation of pain (descending pain related inputs without nociceptor discharge) alters motor unit discharge, and to observe motor unit discharge recovery after pain has ceased. Motor unit discharge was recorded with fine-wire electrodes in the quadriceps of 9 volunteers. Subjects matched isometric knee-extension force during anticipation of pain (anticipation: electrical shocks randomly applied over the infrapatellar fat-pad); pain (hypertonic saline injected into the fat-pad); and 3 intervening control conditions. Discharge rate of motor units decreased during pain (P<.001) and anticipation (P<.01) compared with control contractions. De-recruitment of 1 population of units and new recruitment of another population were observed during both anticipation and pain; some changes in motor unit recruitment persisted after pain ceased. This challenges the fundamental theory that pain-related changes in muscle activity result from direct nociceptor discharge, and provides a mechanism that may underlie long-term changes in movement/chronicity in some musculoskeletal conditions.
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Moving differently in pain: A new theory to explain the adaptation to pain. Pain 2011; 152:S90-S98. [PMID: 21087823 DOI: 10.1016/j.pain.2010.10.020] [Citation(s) in RCA: 612] [Impact Index Per Article: 47.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 10/15/2010] [Accepted: 10/18/2010] [Indexed: 11/20/2022]
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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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