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Sample records for corticospinal motor system

  1. Mapping genetic influences on the corticospinal motor system in humans

    DEFF Research Database (Denmark)

    Cheeran, B J; Ritter, C; Rothwell, J C

    2009-01-01

    It is becoming increasingly clear that genetic variations account for a certain amount of variance in the acquisition and maintenance of different skills. Until now, several levels of genetic influences were examined, ranging from global heritability estimates down to the analysis...... of the contribution of single nucleotide polymorphisms (SNP) and variable number tandem repeats. In humans, the corticospinal motor system is essential to the acquisition of fine manual motor skills which require a finely tuned coordination of activity in distal forelimb muscles. Here we review recent brain mapping...

  2. Emergence of gamma motor activity in an artificial neural network model of the corticospinal system.

    Science.gov (United States)

    Grandjean, Bernard; Maier, Marc A

    2017-02-01

    Muscle spindle discharge during active movement is a function of mechanical and neural parameters. Muscle length changes (and their derivatives) represent its primary mechanical, fusimotor drive its neural component. However, neither the action nor the function of fusimotor and in particular of γ-drive, have been clearly established, since γ-motor activity during voluntary, non-locomotor movements remains largely unknown. Here, using a computational approach, we explored whether γ-drive emerges in an artificial neural network model of the corticospinal system linked to a biomechanical antagonist wrist simulator. The wrist simulator included length-sensitive and γ-drive-dependent type Ia and type II muscle spindle activity. Network activity and connectivity were derived by a gradient descent algorithm to generate reciprocal, known target α-motor unit activity during wrist flexion-extension (F/E) movements. Two tasks were simulated: an alternating F/E task and a slow F/E tracking task. Emergence of γ-motor activity in the alternating F/E network was a function of α-motor unit drive: if muscle afferent (together with supraspinal) input was required for driving α-motor units, then γ-drive emerged in the form of α-γ coactivation, as predicted by empirical studies. In the slow F/E tracking network, γ-drive emerged in the form of α-γ dissociation and provided critical, bidirectional muscle afferent activity to the cortical network, containing known bidirectional target units. The model thus demonstrates the complementary aspects of spindle output and hence γ-drive: i) muscle spindle activity as a driving force of α-motor unit activity, and ii) afferent activity providing continuous sensory information, both of which crucially depend on γ-drive.

  3. Motor Skill Learning and Corticospinal Excitability

    DEFF Research Database (Denmark)

    Christiansen, Lasse

    Background Motor skill learning (MSL) is the persistent increase in performance of a skill obtained through practice. This process is associated with changes throughout the central nervous system. One of these is a change in corticospinal excitability (CSE) assessable with Transcranial Magnetic...... Stimulation. Prior work has demonstrated such a change to very different extents with and without causally linking it to the improvements in motor performance. Objectives The aim of this PhD project has been to explore the relation between changes in CSE and motor performance over the time course of learning...... a novel visuomotor skill. I hypothesized that changes in CSE accompanying long-term motor practice relate to the process of learning rather than repetitive practice on an acquired skill and investigated this by incrementally increasing task difficulty and thus postponing saturation of learning...

  4. Motor Skill Learning and Corticospinal Excitability

    DEFF Research Database (Denmark)

    Christiansen, Lasse

    Background Motor skill learning (MSL) is the persistent increase in performance of a skill obtained through practice. This process is associated with changes throughout the central nervous system. One of these is a change in corticospinal excitability (CSE) assessable with Transcranial Magnetic...... Stimulation. Prior work has demonstrated such a change to very different extents with and without causally linking it to the improvements in motor performance. Objectives The aim of this PhD project has been to explore the relation between changes in CSE and motor performance over the time course of learning...... a novel visuomotor skill. I hypothesized that changes in CSE accompanying long-term motor practice relate to the process of learning rather than repetitive practice on an acquired skill and investigated this by incrementally increasing task difficulty and thus postponing saturation of learning...

  5. SENSORIMOTOR INTEGRATION BY CORTICOSPINAL SYSTEM

    Directory of Open Access Journals (Sweden)

    Yunuen eMoreno-López

    2016-03-01

    Full Text Available The corticospinal (CS tract is a complex system which targets several areas of the spinal cord. In particular, the CS descending projection plays a major role in motor command, which results from direct and indirect control of spinal cord pre-motor interneurons as well as motoneurons. But in addition, this system is also involved in a selective and complex modulation of sensory feedback. Despite recent evidence confirms that CS projections drive distinct segmental neural circuits that are part of the sensory and pre-motor pathways, little is known about the spinal networks engaged by the corticospinal tract, the organization of CS projections, the intracortical microcircuitry, and the synaptic interactions in the sensorimotor cortex that may encode different cortical outputs to the spinal cord. Here is stressed the importance of integrated approaches for the study of sensorimotor function of CS system, in order to understand the functional compartmentalization and hierarchical organization of layer 5 output neurons, who are key elements for motor control and hence, of behavior.

  6. A Framework for Understanding the Relationship between Descending Pain Modulation, Motor Corticospinal, and Neuroplasticity Regulation Systems in Chronic Myofascial Pain

    Science.gov (United States)

    Botelho, Leonardo M.; Morales-Quezada, Leon; Rozisky, Joanna R.; Brietzke, Aline P.; Torres, Iraci L. S.; Deitos, Alicia; Fregni, Felipe; Caumo, Wolnei

    2016-01-01

    Myofascial pain syndrome (MPS) is a leading cause of chronic musculoskeletal pain. However, its neurobiological mechanisms are not entirely elucidated. Given the complex interaction between the networks involved in pain process, our approach, to providing insights into the neural mechanisms of pain, was to investigate the relationship between neurophysiological, neurochemical and clinical outcomes such as corticospinal excitability. Recent evidence has demonstrated that three neural systems are affected in chronic pain: (i) motor corticospinal system; (ii) internal descending pain modulation system; and (iii) the system regulating neuroplasticity. In this cross-sectional study, we aimed to examine the relationship between these three central systems in patients with chronic MPS of whom do/do not respond to the Conditioned Pain Modulation Task (CPM-task). The CPM-task was to immerse her non-dominant hand in cold water (0−1°C) to produce a heterotopic nociceptive stimulus. Corticospinal excitability was the primary outcome; specifically, the motor evoked potential (MEP) and intracortical facilitation (ICF) as assessed by transcranial magnetic stimulation (TMS). Secondary outcomes were the cortical excitability parameters [current silent period (CSP) and short intracortical inhibition (SICI)], serum brain-derived neurotrophic factor (BDNF), heat pain threshold (HPT), and the disability related to pain (DRP). We included 33 women, (18–65 years old). The MANCOVA model using Bonferroni's Multiple Comparison Test revealed that non-responders (n = 10) compared to responders (n = 23) presented increased intracortical facilitation (ICF; mean ± SD) 1.43 (0.3) vs. 1.11 (0.12), greater motor-evoked potential amplitude (μV) 1.93 (0.54) vs. 1.40 (0.27), as well a higher serum BDNF (pg/Ml) 32.56 (9.95) vs. 25.59 (10.24), (P pain inhibition was associated with an increase in ICF, serum BDNF levels, and DRP. We propose a framework to explain the relationship and potential

  7. A Framework for Understanding the Relationship between Descending Pain Modulation, Motor Corticospinal, and Neuroplasticity Regulation Systems in Chronic Myofascial Pain.

    Science.gov (United States)

    Botelho, Leonardo M; Morales-Quezada, Leon; Rozisky, Joanna R; Brietzke, Aline P; Torres, Iraci L S; Deitos, Alicia; Fregni, Felipe; Caumo, Wolnei

    2016-01-01

    Myofascial pain syndrome (MPS) is a leading cause of chronic musculoskeletal pain. However, its neurobiological mechanisms are not entirely elucidated. Given the complex interaction between the networks involved in pain process, our approach, to providing insights into the neural mechanisms of pain, was to investigate the relationship between neurophysiological, neurochemical and clinical outcomes such as corticospinal excitability. Recent evidence has demonstrated that three neural systems are affected in chronic pain: (i) motor corticospinal system; (ii) internal descending pain modulation system; and (iii) the system regulating neuroplasticity. In this cross-sectional study, we aimed to examine the relationship between these three central systems in patients with chronic MPS of whom do/do not respond to the Conditioned Pain Modulation Task (CPM-task). The CPM-task was to immerse her non-dominant hand in cold water (0-1°C) to produce a heterotopic nociceptive stimulus. Corticospinal excitability was the primary outcome; specifically, the motor evoked potential (MEP) and intracortical facilitation (ICF) as assessed by transcranial magnetic stimulation (TMS). Secondary outcomes were the cortical excitability parameters [current silent period (CSP) and short intracortical inhibition (SICI)], serum brain-derived neurotrophic factor (BDNF), heat pain threshold (HPT), and the disability related to pain (DRP). We included 33 women, (18-65 years old). The MANCOVA model using Bonferroni's Multiple Comparison Test revealed that non-responders (n = 10) compared to responders (n = 23) presented increased intracortical facilitation (ICF; mean ± SD) 1.43 (0.3) vs. 1.11 (0.12), greater motor-evoked potential amplitude (μV) 1.93 (0.54) vs. 1.40 (0.27), as well a higher serum BDNF (pg/Ml) 32.56 (9.95) vs. 25.59 (10.24), (P pain inhibition was associated with an increase in ICF, serum BDNF levels, and DRP. We propose a framework to explain the relationship and potential

  8. Passive listening to preferred motor tempo modulates corticospinal excitability.

    Science.gov (United States)

    Michaelis, Kelly; Wiener, Martin; Thompson, James C

    2014-01-01

    Rhythms are an essential characteristic of our lives, and auditory-motor coupling affects a variety of behaviors. Previous research has shown that the neural regions associated with motor system processing are coupled to perceptual rhythmic and melodic processing such that the perception of rhythmic stimuli can entrain motor system responses. However, the degree to which individual preference modulates the motor system is unknown. Recent work has shown that passively listening to metrically strong rhythms increases corticospinal excitability, as indicated by transcranial magnetic stimulation (TMS). Furthermore, this effect is modulated by high-groove music, or music that inspires movement, while neuroimaging evidence suggests that premotor activity increases with tempos occurring within a preferred tempo (PT) category. PT refers to the rate of a hypothetical endogenous oscillator that may be indicated by spontaneous motor tempo (SMT) and preferred perceptual tempo (PPT) measurements. The present study investigated whether listening to a rhythm at an individual's PT preferentially modulates motor system excitability. SMT was obtained in human participants through a tapping task in which subjects were asked to tap a response key at their most comfortable rate. Subjects listened a 10-beat tone sequence at 11 log-spaced tempos and rated their preference for each (PPT). We found that SMT and PPT measurements were correlated, indicating that preferred and produced tempos occurred at a similar rate. Crucially, single-pulse TMS delivered to left M1 during PPT judgments revealed that corticospinal excitability, measured by motor-evoked potentials (MEPs), was modulated by tempos traveling closer to individual PT. However, the specific nature of this modulation differed across individuals, with some exhibiting an increase in excitability around PT and others exhibiting a decrease. These findings suggest that auditory-motor coupling induced by rhythms is preferentially

  9. Changes in corticospinal motor excitability induced by non-motor linguistic tasks.

    Science.gov (United States)

    Papathanasiou, I; Filipović, S R; Whurr, R; Rothwell, J C; Jahanshahi, M

    2004-01-01

    "mirror neurons" in perception, the results suggest that activation of motor circuits used in generation of the written output may be an essential part of the perception of the written material as well. Understanding the patterns of task-dependent changes in excitability of the corticospinal motor pathways will provide insights into the organisation of central nervous system functional networks involved in linguistic processes, and may also be useful for future development of novel approaches to rehabilitation therapy of linguistic and motor functions.

  10. Integration of Corticospinal Tractography Reduces Motor Complications After Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Tomoyuki, E-mail: kouga-tky@umin.ac.jp [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan); Shin, Masahiro; Maruyama, Keisuke; Kamada, Kyousuke; Ota, Takahiro [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan); Itoh, Daisuke [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Kunii, Naoto [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan); Ino, Kenji; Aoki, Shigeki; Masutani, Yoshitaka; Igaki, Hiroshi; Onoe, Tsuyoshi [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Saito, Nobuhito [Department of Neurosurgery, University of Tokyo Hospital, Tokyo (Japan)

    2012-05-01

    Purpose: To evaluate whether the use of diffusion-tensor tractography (DTT) of the corticospinal tract could reduce motor complications after stereotactic radiosurgery (SRS). Methods and Materials: Patients with arteriovenous malformation (AVM) in the deep frontal lobe, deep parietal lobe, basal ganglia, and thalamus who had undergone radiosurgery since 2000 and were followed up for more than 3 years were studied. DTT of the corticospinal tract had been integrated into treatment planning of SRS since 2004, and the maximum dose received by the corticospinal tract was attempted to be less than 20 Gy. Treatment outcomes before (28 patients, Group A) and after (24 patients, Group B) the introduction of this technique were compared. Results: There were no statistical differences between the two groups (Group A vs. Group B) in patients' age (34 years vs. 33 years, p = 0.76), percentage of patients with hemorrhagic events before treatment (50% vs. 29%, p = 0.12), or percentage of AVM involving the basal ganglia and thalamus (36% vs. 46%, p = 0.46). Obliteration rates were 69% and 76% at 4 years in Groups A and B, respectively (p = 0.68), which were not significantly different. Motor complications were observed in 5 patients in Group A (17.9%) but only in 1 patient in Group B (4.2%), which was significantly less frequent (p = 0.021). Conclusion: Integrating DTT of the corticospinal tract into treatment planning contributed to reduction of motor complications without compromising the obliteration rate for AVM adjacent to the corticospinal tract.

  11. Motor simulation without motor expertise: enhanced corticospinal excitability in visually experienced dance spectators.

    Directory of Open Access Journals (Sweden)

    Corinne Jola

    Full Text Available The human "mirror-system" is suggested to play a crucial role in action observation and execution, and is characterized by activity in the premotor and parietal cortices during the passive observation of movements. The previous motor experience of the observer has been shown to enhance the activity in this network. Yet visual experience could also have a determinant influence when watching more complex actions, as in dance performances. Here we tested the impact visual experience has on motor simulation when watching dance, by measuring changes in corticospinal excitability. We also tested the effects of empathic abilities. To fully match the participants' long-term visual experience with the present experimental setting, we used three live solo dance performances: ballet, Indian dance, and non-dance. Participants were either frequent dance spectators of ballet or Indian dance, or "novices" who never watched dance. None of the spectators had been physically trained in these dance styles. Transcranial magnetic stimulation was used to measure corticospinal excitability by means of motor-evoked potentials (MEPs in both the hand and the arm, because the hand is specifically used in Indian dance and the arm is frequently engaged in ballet dance movements. We observed that frequent ballet spectators showed larger MEP amplitudes in the arm muscles when watching ballet compared to when they watched other performances. We also found that the higher Indian dance spectators scored on the fantasy subscale of the Interpersonal Reactivity Index, the larger their MEPs were in the arms when watching Indian dance. Our results show that even without physical training, corticospinal excitability can be enhanced as a function of either visual experience or the tendency to imaginatively transpose oneself into fictional characters. We suggest that spectators covertly simulate the movements for which they have acquired visual experience, and that empathic abilities

  12. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function.

    Science.gov (United States)

    Carmel, Jason B; Martin, John H

    2014-01-01

    The corticospinal system-with its direct spinal pathway, the corticospinal tract (CST) - is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that 10 days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay.

  13. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    Directory of Open Access Journals (Sweden)

    Jason B Carmel

    2014-06-01

    Full Text Available The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST—is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that ten days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay.

  14. Effect of Experimental Hand Pain on Training-Induced Changes in Motor Performance and Corticospinal Excitability

    Science.gov (United States)

    Mavromatis, Nicolas; Neige, Cécilia; Gagné, Martin; Reilly, Karen T.; Mercier, Catherine

    2017-01-01

    Pain influences plasticity within the sensorimotor system and the aim of this study was to assess the effect of pain on changes in motor performance and corticospinal excitability during training for a novel motor task. A total of 30 subjects were allocated to one of two groups (Pain, NoPain) and performed ten training blocks of a visually-guided isometric pinch task. Each block consisted of 15 force sequences, and subjects modulated the force applied to a transducer in order to reach one of five target forces. Pain was induced by applying capsaicin cream to the thumb. Motor performance was assessed by a skill index that measured shifts in the speed–accuracy trade-off function. Neurophysiological measures were taken from the first dorsal interosseous using transcranial magnetic stimulation. Overall, the Pain group performed better throughout the training (p = 0.03), but both groups showed similar improvements across training blocks (p < 0.001), and there was no significant interaction. Corticospinal excitability in the NoPain group increased halfway through the training, but this was not observed in the Pain group (Time × Group interaction; p = 0.01). These results suggest that, even when pain does not negatively impact on the acquisition of a novel motor task, it can affect training-related changes in corticospinal excitability. PMID:28165363

  15. Effect of Experimental Hand Pain on Training-Induced Changes in Motor Performance and Corticospinal Excitability

    Directory of Open Access Journals (Sweden)

    Nicolas Mavromatis

    2017-02-01

    Full Text Available Pain influences plasticity within the sensorimotor system and the aim of this study was to assess the effect of pain on changes in motor performance and corticospinal excitability during training for a novel motor task. A total of 30 subjects were allocated to one of two groups (Pain, NoPain and performed ten training blocks of a visually-guided isometric pinch task. Each block consisted of 15 force sequences, and subjects modulated the force applied to a transducer in order to reach one of five target forces. Pain was induced by applying capsaicin cream to the thumb. Motor performance was assessed by a skill index that measured shifts in the speed–accuracy trade-off function. Neurophysiological measures were taken from the first dorsal interosseous using transcranial magnetic stimulation. Overall, the Pain group performed better throughout the training (p = 0.03, but both groups showed similar improvements across training blocks (p < 0.001, and there was no significant interaction. Corticospinal excitability in the NoPain group increased halfway through the training, but this was not observed in the Pain group (Time × Group interaction; p = 0.01. These results suggest that, even when pain does not negatively impact on the acquisition of a novel motor task, it can affect training-related changes in corticospinal excitability.

  16. Fine motor skill training enhances functional plasticity of the corticospinal tract after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2016-01-01

    Full Text Available Following central nervous system injury, axonal sprouts form distal to the injury site and extend into the denervated area, reconstructing neural circuits through neural plasticity. How to facilitate this plasticity has become the key to the success of central nervous system repair. It remains controversial whether fine motor skill training contributes to the recovery of neurological function after spinal cord injury. Therefore, we established a rat model of unilateral corticospinal tract injury using a pyramidal tract cutting method. Horizontal ladder crawling and food ball grasping training procedures were conducted 2 weeks before injury and 3 days after injury. The neurological function of rat forelimbs was assessed at 1, 2, 3, 4, and 6 weeks after injury. Axon growth was observed with biotinylated dextran amine anterograde tracing in the healthy corticospinal tract of the denervated area at different time periods. Our results demonstrate that compared with untrained rats, functional recovery was better in the forelimbs and forepaws of trained rats. The number of axons and the expression of growth associated protein 43 were increased at the injury site 3 weeks after corticospinal tract injury. These findings confirm that fine motor skill training promotes central nervous system plasticity in spinal cord injury rats.

  17. Probing the corticospinal link between the motor cortex and motoneurones: some neglected aspects of human motor cortical function

    DEFF Research Database (Denmark)

    Petersen, Nicolas Caesar; Butler, Jane E.; Taylor, Janet L.

    2010-01-01

    ABSTRACT This review considers the operation of the corticospinal system in primates. There is a relatively widespread cortical area containing corticospinal outputs to a single muscle and thus a motoneurone pool receives corticospinal input from a wide region of cortex. In addition, corticospina...

  18. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    OpenAIRE

    Carmel, Jason B; John eMartin

    2014-01-01

    The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST) – is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-d...

  19. Changes in corticospinal drive to spinal motoneurones following visuo-motor skill learning in humans

    DEFF Research Database (Denmark)

    Perez, Monica A.; Jensen, Jesper Lundbye; Nielsen, Jens Bo

    2006-01-01

    We have previously demonstrated an increase in the excitability of the leg motor cortical area in relation to acquisition of a visuo-motor task in healthy humans. It remains unknown whether the interaction between corticospinal drive and spinal motoneurones is also modulated following motor skill...

  20. Corticospinal beta-range coherence is highly dependent on the pre-stationary motor state.

    Science.gov (United States)

    Omlor, Wolfgang; Patino, Luis; Mendez-Balbuena, Ignacio; Schulte-Mönting, Jürgen; Kristeva, Rumyana

    2011-06-01

    During steady muscle contractions, the human sensorimotor cortex generates oscillations in the beta-frequency range (15-30 Hz) that are coherent with the activity of contralateral spinal motoneurons. This corticospinal coherence is thought to favor stationary motor states, but its mode of operation remains elusive. We hypothesized that corticospinal beta-range coherence depends on the sensorimotor processing state before a steady force task and may thus increase after sensorimotor tuning to dynamic force generation. To test this hypothesis we instructed 16 human subjects to compensate static force after rest as well as after compensating predictable or unpredictable dynamic force with their right index finger. We calculated EEG-EMG coherence, cortical motor spectral power, and the motor performance during the force conditions. Corticospinal beta-coherence during stationary force was excessively elevated if the steady-state contraction was preceded by predictable dynamic force instead of rest, and was highest after unpredictable dynamic force. The beta-power decreased from rest to predictable dynamic force, and was lowest during unpredictable dynamic force. The increase in corticospinal beta-coherence showed a significant negative correlation with the preceding change in beta-power. The tuning to dynamic force did not entail an inferior motor performance during static force. The results imply a correlation between corticospinal beta-range coherence and the computational load of the preceding isometric motor engagement. We suggest beta-range coherence provides a functional corticospinal gateway for steady force-related processing that can override cortical states tuned to dynamic force. The modulation of corticospinal beta-range coherence might thus ensure comparable precision of static force in various motor contexts.

  1. Existing Motor State Is Favored at the Expense of New Movement during 13-35 Hz Oscillatory Synchrony in the Human Corticospinal System

    National Research Council Canada - National Science Library

    Gilbertson, Thomas; Lalo, Elodie; Doyle, Louise; Di Lazzaro, Vincenzo; Cioni, Beatrice; Brown, Peter

    2005-01-01

    .... Three experiments were performed. First, healthy subjects were instructed to make reaction time movements of the outstretched index finger in response to imperative cues triggered by transient increases in corticospinal synchrony...

  2. Motor Simulation without Motor Expertise: Enhanced Corticospinal Excitability in Visually Experienced Dance Spectators

    Science.gov (United States)

    Jola, Corinne; Abedian-Amiri, Ali; Kuppuswamy, Annapoorna; Pollick, Frank E.; Grosbras, Marie-Hélène

    2012-01-01

    The human “mirror-system” is suggested to play a crucial role in action observation and execution, and is characterized by activity in the premotor and parietal cortices during the passive observation of movements. The previous motor experience of the observer has been shown to enhance the activity in this network. Yet visual experience could also have a determinant influence when watching more complex actions, as in dance performances. Here we tested the impact visual experience has on motor simulation when watching dance, by measuring changes in corticospinal excitability. We also tested the effects of empathic abilities. To fully match the participants' long-term visual experience with the present experimental setting, we used three live solo dance performances: ballet, Indian dance, and non-dance. Participants were either frequent dance spectators of ballet or Indian dance, or “novices” who never watched dance. None of the spectators had been physically trained in these dance styles. Transcranial magnetic stimulation was used to measure corticospinal excitability by means of motor-evoked potentials (MEPs) in both the hand and the arm, because the hand is specifically used in Indian dance and the arm is frequently engaged in ballet dance movements. We observed that frequent ballet spectators showed larger MEP amplitudes in the arm muscles when watching ballet compared to when they watched other performances. We also found that the higher Indian dance spectators scored on the fantasy subscale of the Interpersonal Reactivity Index, the larger their MEPs were in the arms when watching Indian dance. Our results show that even without physical training, corticospinal excitability can be enhanced as a function of either visual experience or the tendency to imaginatively transpose oneself into fictional characters. We suggest that spectators covertly simulate the movements for which they have acquired visual experience, and that empathic abilities heighten

  3. Intraoperative tractography and motor evoked potential (MEP) monitoring in surgery for gliomas around the corticospinal tract.

    Science.gov (United States)

    Maesawa, Satoshi; Fujii, Masazumi; Nakahara, Norimoto; Watanabe, Tadashi; Wakabayashi, Toshihiko; Yoshida, Jun

    2010-07-01

    Our goal is to indicate the importance of combining intraoperative tractography with motor-evoked potential (MEP) monitoring for glioma surgery in motor eloquent areas. Tumor removal was performed in 28 patients with gliomas in and around the corticospinal tract (CST), in an operation theater equipped with an integrated high-field intraoperative magnetic resonance imaging and a neuronavigation system. Diffusion-tensor imaging-based tractography of the CST was implemented preoperatively and intraoperatively. When the surgically manipulated area came close to the corticospinal pathway, MEP responses were elicited by subcortical stimulation. Responsive areas were compared with the locations of fibers traced by preoperative and intraoperative tractography. Imaging and functional outcomes were reviewed. Intraoperative tractography demonstrated significant inward or outward shift during surgery. MEP responses were observed around the tract at various intensities, and the distance between MEP responsive sites and intraoperative tractography was significantly correlated with the stimulation intensity (P < 0.01). The distance from preoperative tractography was not correlated. A more than subtotal resection was achieved in 24 patients (85.7%). Transient motor deterioration was seen in 12 patients (42.8%), and a permanent deficit was seen in 1 patient (3.5%). We found that intraoperative tractography demonstrated the location of the CST more accurately than preoperative tractography. The results of the linear regression between distance and stimulation intensity were informative for guiding approaches to tumor remnants without impinging on the CST. The combination of intraoperative tractography and MEP monitoring can enhance the quality of surgery for gliomas in motor eloquent areas. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Corticospinal Reorganization after Locomotor Training in a Person with Motor Incomplete Paraplegia

    Directory of Open Access Journals (Sweden)

    Nupur Hajela

    2013-01-01

    Full Text Available Activity-dependent plasticity as a result of reorganization of neural circuits is a fundamental characteristic of the central nervous system that occurs simultaneously in multiple sites. In this study, we established the effects of subthreshold transcranial magnetic stimulation (TMS over the primary motor cortex region on the tibialis anterior (TA long-latency flexion reflex. Neurophysiological tests were conducted before and after robotic gait training in one person with a motor incomplete spinal cord injury (SCI while at rest and during robotic-assisted stepping. The TA flexion reflex was evoked following nonnociceptive sural nerve stimulation and was conditioned by TMS at 0.9 TA motor evoked potential resting threshold at conditioning-test intervals that ranged from 70 to 130 ms. Subthreshold TMS induced a significant facilitation on the TA flexion reflex before training, which was reversed to depression after training with the subject seated at rest. During stepping, corticospinal facilitation of the flexion reflex at early and midstance phases before training was replaced with depression at early and midswing followed by facilitation at late swing after training. These results constitute the first neurophysiologic evidence that locomotor training reorganizes the cortical control of spinal interneuronal circuits that generate patterned motor activity, modifying spinal reflex function, in the chronic lesioned human spinal cord.

  5. Motor cortex and spinal cord neuromodulation promote corticospinal tract axonal outgrowth and motor recovery after cervical contusion spinal cord injury.

    Science.gov (United States)

    Zareen, N; Shinozaki, M; Ryan, D; Alexander, H; Amer, A; Truong, D Q; Khadka, N; Sarkar, A; Naeem, S; Bikson, M; Martin, J H

    2017-08-10

    Cervical injuries are the most common form of SCI. In this study, we used a neuromodulatory approach to promote skilled movement recovery and repair of the corticospinal tract (CST) after a moderately severe C4 midline contusion in adult rats. We used bilateral epidural intermittent theta burst (iTBS) electrical stimulation of motor cortex to promote CST axonal sprouting and cathodal trans-spinal direct current stimulation (tsDCS) to enhance spinal cord activation to motor cortex stimulation after injury. We used Finite Element Method (FEM) modeling to direct tsDCS to the cervical enlargement. Combined iTBS-tsDCS was delivered for 30min daily for 10days. We compared the effect of stimulation on performance in the horizontal ladder and the Irvine Beattie and Bresnahan forepaw manipulation tasks and CST axonal sprouting in injury-only and injury+stimulation animals. The contusion eliminated the dorsal CST in all animals. tsDCS significantly enhanced motor cortex evoked responses after C4 injury. Using this combined spinal-M1 neuromodulatory approach, we found significant recovery of skilled locomotion and forepaw manipulation skills compared with injury-only controls. The spared CST axons caudal to the lesion in both animal groups derived mostly from lateral CST axons that populated the contralateral intermediate zone. Stimulation enhanced injury-dependent CST axonal outgrowth below and above the level of the injury. This dual neuromodulatory approach produced partial recovery of skilled motor behaviors that normally require integration of posture, upper limb sensory information, and intent for performance. We propose that the motor systems use these new CST projections to control movements better after injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Motor imagery of voluntary muscle relaxation induces temporal reduction of corticospinal excitability.

    Science.gov (United States)

    Kato, Kouki; Watanabe, Jun; Muraoka, Tetsuro; Kanosue, Kazuyuki

    2015-03-01

    Voluntary muscle relaxation is an "active process" requiring cortical activation. However, cortical activation during motor imagery of muscle relaxation has not been well understood. The purpose of this study was to clarify time-dependent changes in corticospinal excitability during the imagery of muscle relaxation. Ten participants imagined volitional muscle relaxation from an imagined pinching with their right index finger and thumb in response to an auditory cue. Transcranial magnetic stimulation was applied at the left primary motor area of the first dorsal interosseous (FDI) muscle at different time intervals after the auditory cue. Motor evoked potentials (MEPs) were recorded from the right hand and forearm muscles. The MEP amplitudes of the FDI and the synergist temporally decreased after the auditory cue as compared with those present in the resting condition. Our finding indicates that motor imagery of muscle relaxation induces a temporal reduction of the corticospinal excitability related to the targeted muscle. Copyright © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  7. Transcutaneous spinal direct current stimulation modulates human corticospinal system excitability.

    Science.gov (United States)

    Bocci, Tommaso; Marceglia, Sara; Vergari, Maurizio; Cognetto, Valeria; Cogiamanian, Filippo; Sartucci, Ferdinando; Priori, Alberto

    2015-07-01

    This study aimed to assess the effects of thoracic anodal and cathodal transcutaneous spinal direct current stimulation (tsDCS) on upper and lower limb corticospinal excitability. Although there have been studies assessing how thoracic tsDCS influences the spinal ascending tract and reflexes, none has assessed the effects of this technique over upper and lower limb corticomotor neuronal connections. In 14 healthy subjects we recorded motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) from abductor hallucis (AH) and hand abductor digiti minimi (ADM) muscles before (baseline) and at different time points (0 and 30 min) after anodal or cathodal tsDCS (2.5 mA, 20 min, T9-T11 level). In 8 of the 14 subjects we also tested the soleus H reflex and the F waves from AH and ADM before and after tsDCS. Both anodal and cathodal tsDCS left the upper limb MEPs and F wave unchanged. Conversely, while leaving lower limb H reflex unchanged, they oppositely affected lower limb MEPs: whereas anodal tsDCS increased resting motor threshold [(mean ± SE) 107.33 ± 3.3% increase immediately after tsDCS and 108.37 ± 3.2% increase 30 min after tsDCS compared with baseline] and had no effects on MEP area and latency, cathodal tsDCS increased MEP area (139.71 ± 12.9% increase immediately after tsDCS and 132.74 ± 22.0% increase 30 min after tsDCS compared with baseline) without affecting resting motor threshold and MEP latency. Our results show that tsDCS induces polarity-specific changes in corticospinal excitability that last for >30 min after tsDCS offset and selectively affect responses in lower limb muscles innervated by lumbar and sacral motor neurons.

  8. Corticospinal excitability in human voluntary movement

    NARCIS (Netherlands)

    Elswijk, G.A.F. van

    2008-01-01

    The research described in this thesis addressed the neurophysiologic changes in the human corticospinal system during preparation and execution of voluntary hand movements. The experiments involved transcranial magnetic stimulation (TMS) of the motor cortex combined with electromyography (EMG) and e

  9. Functional Assessment of Corticospinal System Excitability in Karate Athletes.

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    Fiorenzo Moscatelli

    Full Text Available To investigate the involvement of the primary motor cortex (M1 in the coordination performance of karate athletes through transcranial magnetic stimulation (TMS.Thirteen right-handed male karate athletes (25.0±5.0 years and 13 matched non-athlete controls (26.7±6.2 years were enrolled. A single-pulse TMS was applied using a figure-eight coil stimulator. Resting motor threshold (rMT was determined. Surface electromyography was recorded from the first dorsal interosseous muscle. Motor evoked potential (MEP latencies and amplitudes at rMT, 110%, and 120% of rMT were considered. Functional assessment of the coordination performance was assessed by in-phase (IP and anti-phase (AP homolateral hand and foot coordination tasks performed at 80, 120, and 180 bpm.Compared to controls, athletes showed lower rMT (p<0.01, shorter MEP latency (p<0.01 and higher MEP amplitude (p<0.01, with a significant correlation (r = 0.50, p<0.01 between rMT and MEP latency. Coordination decreased with increasing velocity, and better IP performances emerged compared to AP ones (p<0.001. In general, a high correlation between rMT and coordination tasks was found for both IP and AP conditions.With respect to controls, karate athletes present a higher corticospinal excitability indicating the presence of an activity-dependent alteration in the balance and interactions between inhibitory and facilitatory circuits determining the final output from the M1. Furthermore, the high correlation between corticospinal excitability and coordination performance could support sport-specific neurophysiological arrangements.

  10. Functional motor recovery from motoneuron axotomy is compromised in mice with defective corticospinal projections.

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    Yuetong Ding

    Full Text Available Brachial plexus injury (BPI and experimental spinal root avulsion result in loss of motor function in the affected segments. After root avulsion, significant motoneuron function is restored by re-implantation of the avulsed root. How much this functional recovery depends on corticospinal inputs is not known. Here, we studied that question using Celsr3|Emx1 mice, in which the corticospinal tract (CST is genetically absent. In adult mice, we tore off right C5-C7 motor and sensory roots and re-implanted the right C6 roots. Behavioral studies showed impaired recovery of elbow flexion in Celsr3|Emx1 mice compared to controls. Five months after surgery, a reduced number of small axons, and higher G-ratio of inner to outer diameter of myelin sheaths were observed in mutant versus control mice. At early stages post-surgery, mutant mice displayed lower expression of GAP-43 in spinal cord and of myelin basic protein (MBP in peripheral nerves than control animals. After five months, mutant animals had atrophy of the right biceps brachii, with less newly formed neuromuscular junctions (NMJs and reduced peak-to-peak amplitudes in electromyogram (EMG, than controls. However, quite unexpectedly, a higher motoneuron survival rate was found in mutant than in control mice. Thus, following root avulsion/re-implantation, the absence of the CST is probably an important reason to hamper axonal regeneration and remyelination, as well as target re-innervation and formation of new NMJ, resulting in lower functional recovery, while fostering motoneuron survival. These results indicate that manipulation of corticospinal transmission may help improve functional recovery following BPI.

  11. Real-time changes in corticospinal excitability related to motor imagery of a force control task.

    Science.gov (United States)

    Tatemoto, Tsuyoshi; Tsuchiya, Junko; Numata, Atsuki; Osawa, Ryuji; Yamaguchi, Tomofumi; Tanabe, Shigeo; Kondo, Kunitsugu; Otaka, Yohei; Sugawara, Kenichi

    2017-09-29

    To investigate real-time excitability changes in corticospinal pathways related to motor imagery in a changing force control task, using transcranial magnetic stimulation (TMS). Ten healthy volunteers learnt to control the contractile force of isometric right wrist dorsiflexion in order to track an on-screen sine wave form. Participants performed the trained task 40 times with actual muscle contraction in order to construct the motor image. They were then instructed to execute the task without actual muscle contraction, but by imagining contraction of the right wrist in dorsiflexion. Motor evoked potentials (MEPs), induced by TMS in the right extensor carpi radialis muscle (ECR) and flexor carpi radialis muscle (FCR), were measured during motor imagery. MEPs were induced at five time points: prior to imagery, during the gradual generation of the imaged wrist dorsiflexion (Increasing phase), the peak value of the sine wave, during the gradual reduction (Decreasing phase), and after completion of the task. The MEP ratio, as the ratio of imaged MEPs to resting-state, was compared between pre- and post-training at each time point. In the ECR muscle, the MEP ratio significantly increased during the Increasing phase and at the peak force of dorsiflexion imagery after training. Moreover, the MEP ratio was significantly greater in the Increasing phase than in the Decreasing phase. In the FCR, there were no significant consistent changes. Corticospinal excitability during motor imagery in an isometric contraction task was modulated in relation to the phase of force control after image construction. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Differences in corticospinal system activity and reaction response between karate athletes and non-athletes.

    Science.gov (United States)

    Moscatelli, Fiorenzo; Messina, Giovanni; Valenzano, Anna; Petito, Annamaria; Triggiani, Antonio Ivano; Messina, Antonietta; Monda, Vincenzo; Viggiano, Andrea; De Luca, Vincenzo; Capranica, Laura; Monda, Marcellino; Cibelli, Giuseppe

    2016-12-01

    The aim of this study was to verify the hypothesis that transcranial magnetic stimulation (TMS) parameters over the hand region of the motor cortex, such as resting motor threshold (rMT) and motor evoked potential (MEP) latency, predict the behavioural performance of karate athletes in the response time (RT) test. Twenty-five male karate athletes (24.9 ± 4.9 years) and 25 matched non-athletes (26.2 ± 4.5 years) were recruited. Using TMS, we investigated cortico-spinal system excitability. Compared with controls, the athletes showed faster RT (p rMT (p rMT (p rMT and the shorter MEP latency observed in athletes support the effects of training in determining specific brain organizations to meet specific sport challenges.

  13. Tractography of the corticospinal tracts in infants with focal perinatal injury : comparison with normal controls and to motor development

    NARCIS (Netherlands)

    Roze, Elise; Harris, Polly A.; Ball, Gareth; Zubiaurre Elorza, Leire; Braga, Rodrigo M.; Allsop, Joanna M.; Merchant, Nazakat; Porter, Emma; Arichi, Tomoki; Edwards, A. David; Rutherford, Mary A.; Cowan, Frances M.; Counsell, Serena J.

    2012-01-01

    Our aims were to (1) assess the corticospinal tracts (CSTs) in infants with focal injury and healthy term controls using probabilistic tractography and (2) to correlate the conventional magnetic resonance imaging (MRI) and tractography findings in infants with focal injury with their later motor fun

  14. The effect of electrical stimulation of the corticospinal tract on motor units of the human biceps brachii

    DEFF Research Database (Denmark)

    Petersen, Nicolas Caesar; Taylor, Janet L; Gandevia, Simon C

    2002-01-01

    In healthy human subjects, descending motor pathways including the corticospinal tract were stimulated electrically at the level of the cervicomedullary junction to determine the effects on the discharge of motoneurones innervating the biceps brachii. Post-stimulus time histograms (PSTHs) were co...

  15. Contribution of corticospinal tract and functional connectivity in hand motor impairment after stroke.

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    Charlotte Rosso

    Full Text Available BACKGROUND: Motor outcome after stroke is associated with reorganisation of cortical networks and corticospinal tract (CST integrity. However, the relationships between motor severity, CST damage, and functional brain connectivity are not well understood. Here, the main objective was to study the effect of CST damage on the relationship between functional motor network connectivity and hand motor function in two groups of stroke patients: the severely (n=8 and the mildly impaired (n=14. METHODS: Twenty-two carotid stroke patients with motor deficits were studied with magnetic resonance imaging (MRI at 3 weeks, at 3 and 6 months. Healthy subjects (n=28 were scanned once. The CST injury was assessed by fractional anisotropy values. Functional connectivity was studied from a whole-hand grip task fMRI in a cortical and cerebellar motor network. Functional connectivity indexes were computed between these regions at each time point. The relationship between hand motor strength, ipsilesional CST damage and functional connectivity from the primary motor cortex (M1 was investigated using global and partial correlations. FINDINGS: In mildly impaired patients, cortico-cortical connectivity was disturbed at three weeks but returned to a normal pattern after 3 months. Cortico-cerebellar connectivity was still decreased at 6 months. In severely impaired patients, the cortico-cortical connectivity tended to return to a normal pattern, but the cortico-cerebellar connectivity was totally abolished during the follow-up. In the entire group of patients, the hand motor strength was correlated to the ipsilesional functional connectivity from M1. Partial correlations revealed that these associations were not anymore significant when the impact of CST damage was removed, except for the ipsilesional M1-contralateral cerebellum connectivity. CONCLUSION: Functional brain connectivity changes can be observed, even in severely impaired patients with no recovery. Upper limb

  16. Influence of Corticospinal Tracts from Higher Order Motor Cortices on Recruitment Curve Properties in Stroke

    Science.gov (United States)

    Potter-Baker, Kelsey A.; Varnerin, Nicole M.; Cunningham, David A.; Roelle, Sarah M.; Sankarasubramanian, Vishwanath; Bonnett, Corin E.; Machado, Andre G.; Conforto, Adriana B.; Sakaie, Ken; Plow, Ela B.

    2016-01-01

    Background: Recruitment curves (RCs) acquired using transcranial magnetic stimulation are commonly used in stroke to study physiologic functioning of corticospinal tracts (CST) from M1. However, it is unclear whether CSTs from higher motor cortices contribute as well. Objective: To explore whether integrity of CST from higher motor areas, besides M1, relates to CST functioning captured using RCs. Methods: RCs were acquired for a paretic hand muscle in patients with chronic stroke. Metrics describing gain and overall output of CST were collected. CST integrity was defined by diffusion tensor imaging. For CST emerging from M1 and higher motor areas, integrity (fractional anisotropy) was evaluated in the region of the posterior limb of the internal capsule, the length of CST and in the region of the stroke lesion. Results: We found that output and gain of RC was related to integrity along the length of CST emerging from higher motor cortices but not the M1. Conclusions: Our results suggest that RC parameters in chronic stroke infer function primarily of CST descending from the higher motor areas but not M1. RCs may thus serve as a simple, in-expensive means to assess re-mapping of alternate areas that is generally studied with resource-intensive neuroimaging in stroke. PMID:27013942

  17. Corticospinal activity evoked and modulated by non-invasive stimulation of the intact human motor cortex.

    Science.gov (United States)

    Di Lazzaro, Vincenzo; Rothwell, John C

    2014-10-01

    A number of methods have been developed recently that stimulate the human brain non-invasively through the intact scalp. The most common are transcranial magnetic stimulation (TMS), transcranial electric stimulation (TES) and transcranial direct current stimulation (TDCS). They are widely used to probe function and connectivity of brain areas as well as therapeutically in a variety of conditions such as depression or stroke. They are much less focal than conventional invasive methods which use small electrodes placed on or in the brain and are often thought to activate all classes of neurones in the stimulated area. However, this is not true. A large body of evidence from experiments on the motor cortex shows that non-invasive methods of brain stimulation can be surprisingly selective and that adjusting the intensity and direction of stimulation can activate different classes of inhibitory and excitatory inputs to the corticospinal output cells. Here we review data that have elucidated the action of TMS and TES, concentrating mainly on the most direct evidence available from spinal epidural recordings of the descending corticospinal volleys. The results show that it is potentially possible to test and condition specific neural circuits in motor cortex that could be affected differentially by disease, or be used in different forms of natural behaviour. However, there is substantial interindividual variability in the specificity of these protocols. Perhaps in the future it will be possible, with the advances currently being made to model the electrical fields induced in individual brains, to develop forms of stimulation that can reliably target more specific populations of neurones, and open up the internal circuitry of the motor cortex for study in behaving humans.

  18. Activation of less affected corticospinal tract and poor motor outcome in hemiplegic pediatric patients: a diffusion tensor tractography imaging study

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    Jin Hyun Kim

    2015-01-01

    Full Text Available The less affected hemisphere is important in motor recovery in mature brains. However, in terms of motor outcome in immature brains, no study has been reported on the less affected corticospinal tract in hemiplegic pediatric patients. Therefore, we examined the relationship between the condition of the less affected corticospinal tract and motor function in hemiplegic pediatric patients. Forty patients with hemiplegia due to perinatal or prenatal injury (13.7 ± 3.0 months and 40 age-matched typically developing controls were recruited. These patients were divided into two age-matched groups, the high functioning group (20 patients and the low functioning group (20 patients using functional level of hemiplegia scale. Diffusion tensor tractography images showed that compared with the control group, the patient group of the less affected corticospinal tract showed significantly increased fiber number and significantly decreased fractional anisotropy value. Significantly increased fiber number and significantly decreased fractional anisotropy value in the low functioning group were observed than in the high functioning group. These findings suggest that activation of the less affected hemisphere presenting as increased fiber number and decreased fractional anisotropy value is related to poor motor function in pediatric hemiplegic patients.

  19. Activation of less affected corticospinal tract and poor motor outcome in hemiplegic pediatric patients: a diffusion tensor tractography imaging study.

    Science.gov (United States)

    Kim, Jin Hyun; Son, Su Min

    2015-12-01

    The less affected hemisphere is important in motor recovery in mature brains. However, in terms of motor outcome in immature brains, no study has been reported on the less affected corticospinal tract in hemiplegic pediatric patients. Therefore, we examined the relationship between the condition of the less affected corticospinal tract and motor function in hemiplegic pediatric patients. Forty patients with hemiplegia due to perinatal or prenatal injury (13.7 ± 3.0 months) and 40 age-matched typically developing controls were recruited. These patients were divided into two age-matched groups, the high functioning group (20 patients) and the low functioning group (20 patients) using functional level of hemiplegia scale. Diffusion tensor tractography images showed that compared with the control group, the patient group of the less affected corticospinal tract showed significantly increased fiber number and significantly decreased fractional anisotropy value. Significantly increased fiber number and significantly decreased fractional anisotropy value in the low functioning group were observed than in the high functioning group. These findings suggest that activation of the less affected hemisphere presenting as increased fiber number and decreased fractional anisotropy value is related to poor motor function in pediatric hemiplegic patients.

  20. Motor Cortex Activity Organizes the Developing Rubrospinal System.

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    Williams, Preston T J A; Martin, John H

    2015-09-30

    The corticospinal and rubrospinal systems function in skilled movement control. A key question is how do these systems develop the capacity to coordinate their motor functions and, in turn, if the red nucleus/rubrospinal tract (RN/RST) compensates for developmental corticospinal injury? We used the cat to investigate whether the developing rubrospinal system is shaped by activity-dependent interactions with the developing corticospinal system. We unilaterally inactivated M1 by muscimol microinfusion between postnatal weeks 5 and 7 to examine activity-dependent interactions and whether the RN/RST compensates for corticospinal tract (CST) developmental motor impairments and CST misprojections after M1 inactivation. We examined the RN motor map and RST cervical projections at 7 weeks of age, while the corticospinal system was inactivated, and at 14 weeks, after activity returned. During M1 inactivation, the RN on the same side showed normal RST projections and reduced motor thresholds, suggestive of precocious development. By contrast, the RN on the untreated/active M1 side showed sparse RST projections and an immature motor map. After M1 activity returned later in adolescent cat development, RN on the active M1/CST side continued to show a substantial loss of spinal terminations and an impaired motor map. RN/RST on the inactivated side regressed to a smaller map and fewer axons. Our findings suggest that the developing rubrospinal system is under activity-dependent regulation by the corticospinal system for establishing mature RST connections and RN motor map. The lack of RS compensation on the non-inactivated side can be explained by development of ipsilateral misprojections from the active M1 that outcompete the RST. Significance statement: Skilled movements reflect the activity of multiple descending motor systems and their interactions with spinal motor circuits. Currently, there is little insight into whether motor systems interact during development to

  1. Brain-Computer Interface Therapy after Stroke Affects Patterns of Brain-Behavior Relationships in Corticospinal Motor Fibers

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    Brittany Mei Young

    2016-09-01

    Full Text Available Background. Brain-computer interface (BCI devices are being investigated for their application in stroke rehabilitation, but little is known about how structural changes in the motor system relate to behavioral measures with the use of these systems. Objective. This study examined relationships among diffusion tensor imaging (DTI-derived metrics and with behavioral changes in stroke patients with and without BCI training. Methods. Stroke patients (n=19 with upper extremity motor impairment were assessed using Stroke Impact Scale (SIS, Action Research Arm Test (ARAT, Nine-Hole Peg Test (9-HPT, and DTI scans. Ten subjects completed four assessments over a control period during which no training was administered. Seventeen subjects, including eight who completed the control period, completed four assessments over an experimental period during which subjects received interventional BCI training. Fractional anisotropy (FA values were extracted from each corticospinal tract (CST and transcallosal motor fibers for each scan. Results. No significant group by time interactions were identified at the group level in DTI or behavioral measures. During the control period, increases in contralesional CST FA and in asymmetric FA (aFA correlated with poorer scores on SIS and 9-HPT. During the experimental period (with BCI training, increases in contralesional CST FA were correlated with improvements in 9-HPT while increases in aFA correlated with improvements in ARAT but with worsening 9-HPT performance; changes in transcallosal motor fibers positively correlated with those in the contralesional CST. All correlations p<0.05 corrected. Conclusions. These findings suggest that the integrity of the contralesional CST may be used to track individual behavioral changes observed with BCI training after stroke.

  2. Change in connection between corticospinal tract and Broca's area during motor recovery in a patient with an intracerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    Hyeok Gyu Kwon; Sung Ho Jang

    2011-01-01

    The present study reported a 42-year-old male patient who underwent conservative management for a spontaneous intracerebral hemorrhage in the left corona radiata and the basal ganglia. The patient presented with complete weakness of the right upper and lower extremities at the onset of intracerebral hemorrhage; however, he showed progressive motor recovery to the level that he was able to extent the affected extremities against some resistance at 5 weeks after onset. The corticospinal tract of the affected (left) hemisphere connected to the left Broca's area at 3 weeks after onset as shown by diffusion tensor tractography. By contrast, this connection had disappeared at 5 weeks after onset as shown by diffusion tensor tractogaphy. Transcranial magnetic stimulation study showed that no motor evoked potential was elicited from the affected (left) hemisphere at 3 weeks after onset, but motor evoked potentials were elicited at 5 weeks after onset. These findings suggest that the connection between the injured corticospinal tract and Broca's area in this patient appears to be a compensation for severe motor weakness; consequently, the connection seems to disappear with motor recovery.

  3. Investigation of Motor Cortical Plasticity and Corticospinal Tract Diffusion Tensor Imaging in Patients with Parkinsons Disease and Essential Tremor

    Science.gov (United States)

    Chen, Chun-Ming; Duann, Jeng-Ren; Ziemann, Ulf; Chen, Jui-Cheng; Chiou, Shang-Ming; Tsai, Chon-Haw

    2016-01-01

    Parkinson’s disease (PD) and essential tremor (ET) are characterized with motor dysfunctions. Motor circuit dysfunctions can be complementarily investigated by paired associative stimulation (PAS)-induced long-term potentiation (LTP)-like plasticity and diffusion tensor imaging (DTI) of the corticospinal tract (CST). Three groups of twelve subjects with moderate severity PD, ET with intention tremor and healthy controls (HC) were studied. The primary motor cortex (M1) excitability, measured by motor evoked potential (MEP) amplitude and by short-interval and long-interval intracortical inhibition (SICI and LICI) was compared between the three groups before and after PAS. The DTI measures of fractional anisotropy (FA) and mean diffusivity (MD) were acquired. PAS effects and DTI data were simultaneously examined between groups. PAS increased MEP amplitude in HC but not in PD and ET. SICI and LICI were significantly reduced after PAS irrespective of groups. No significant differences of the mean FA and MD were found between groups. There was no significant correlation between the PAS effects and the DTI measures. Findings suggest that both PD and ET with intention tremor have impairment of the associative LTP-like corticospinal excitability change in M1. The microstructure of the CST is not relevant to the deficiency of M1 associative plasticity in PD and ET. PMID:27603204

  4. MRI and diffusion tensor imaging in assessing correlation of activation of cortical motor function and manifestations of corticospinal tract with muscle strength in patients with ischemic stroke

    Institute of Scientific and Technical Information of China (English)

    Ziqian Chen; Hui Xiao; Biyun Zhang; Gennian Qian; Ping Ni; Xizhang Yang

    2006-01-01

    BACKGROUND: Ischemic stroke is often followed by the abnormalities of neurons and corticospinal tract,which can lead to corresponding clinical symptoms and signs. Recently, with the continuous perfection of high-field MRI instrument, it becomes possible to assess and investigate the cortical function and structural reconstruction following stroke by using MRI and diffusion tensor imaging (DTI).OBJECTIVE: To observe the cortical motor function and changes of corticospinal tracts by using MRI and DTI in the patients with ischemic stroke at acute period, compare with the normal subjects, and assess the damage of corticospinal tract and muscle strength.DESIGN: A case-control observation.SETTING: Department of Medical Imaging, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA.PARTICIPANTS: Nine inpatients (5 males and 4 females) with injury of motor function induced by acute ischemic stroke were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA between August and December in 2005, they aged 16-87 years with an average of 51 years old, and those with obvious conscious disturbances and severe cognitive disorders were excluded. At the same time, nine healthy right-handed physical examinees matched by age and gender with the patients were also selected, and they all had no nervous disease, epilepsy, mental diseases, cerebrovascular abnormalities and injury history, etc. All the subjects were informed with the detected items and agreed to participate in.METHODS:All the 9 patients with ischemic stroke at acute period and 9 healthy subjects were examined with MRI and DTI. ① A block-based design was used in the MRI, the passive finger-to-finger exercise was used as the stimulative task, and the static condition was taken as the baseline task. The GE 1.5T MRI system was used, all the data were processed after off-line, and analyzed with the SPM2 software, the association between the activated area and local anatomy of

  5. Beta-range cortical motor spectral power and corticomuscular coherence as a mechanism for effective corticospinal interaction during steady-state motor output.

    Science.gov (United States)

    Kristeva, Rumyana; Patino, Luis; Omlor, Wolfgang

    2007-07-01

    The steady-state motor output, occurring during static force, is characterized by synchronization between oscillatory cortical motor and muscle activity confined to the beta frequency range (15-30 Hz). The functional significance of this beta-range coherence remains unclear. We hypothesized that if the beta-range coherence had a functional role, it would have a behavioral correlate; specifically, it would be related to the precision of the steady-state motor output. To test this hypothesis, we investigated the corticomuscular (EEG-EMG) coherence in eight healthy subjects during steady-state motor output in a visuomotor task, in which the subjects exerted a static force with their right index finger to keep a visual cursor within a target zone. We show that the beta-range EEG-EMG coherence is related to the behavioral performance, i.e. the error signal between target and exerted force. Furthermore, we show that the amplitude of the cortical spectral power is also related to the performance. Moreover, we provide evidence that the EEG-EMG coherence and the cortical spectral power are not completely independent phenomena. Together, our findings indicate that higher beta-range cortical spectral power and increased corticospinal coherence in the beta-range improve motor performance during steady-state motor output. This suggests that the beta-range cortical motor spectral power and corticomuscular coherence may promote effective corticospinal interaction.

  6. Corticospinal tract integrity and lesion volume play different roles in chronic hemiparesis and its improvement through motor practice.

    Science.gov (United States)

    Sterr, Annette; Dean, Phil J A; Szameitat, Andre J; Conforto, Adriana Bastos; Shen, Shan

    2014-05-01

    Initial evidence suggests that the integrity of the ipsilesional corticospinal tract (CST) after stroke is strongly related to motor function in the chronic state but not the treatment gain induced by motor rehabilitation. We examined the association of motor status and treatment benefit by testing patients with a wide range of severity of hemiparesis of the left and right upper extremity. Diffusion tensor imaging was performed in 22 patients beyond 12 months after onset of stroke with severe to moderate hemiparesis. Motor function was tested before and after 2 weeks of modified constraint-induced movement therapy. CST integrity, but not lesion volume, correlated with the motor ability measures of the Wolf Motor Function Test and the Motor Activity Log. No differences were found between left and right hemiparesis. Motor performance improved significantly with the treatment regime, and did so equally for patients with left and right arm paresis. However, treatment benefit was not associated with either CST integrity or lesion volume. CST integrity correlated best in this small trial with chronic long-term status but not treatment-induced improvements. The CST may play a different role in the mechanisms mediating long-term outcome compared to those underlying practice-induced gains after a chronic plateau in motor function.

  7. Tractography of the corticospinal tracts in infants with focal perinatal injury: comparison with normal controls and to motor development

    Energy Technology Data Exchange (ETDEWEB)

    Roze, Elise [Imperial College, Centre for the Developing Brain, London (United Kingdom); Hammersmith Hospital, Robert Steiner MR Unit, MRC Clinical Sciences Centre, London (United Kingdom); University Medical Center Groningen, Division of Neonatology, Beatrix Children' s Hospital, Groningen (Netherlands); Harris, Polly A.; Ball, Gareth; Braga, Rodrigo M.; Allsop, Joanna M.; Counsell, Serena J. [Imperial College, Centre for the Developing Brain, London (United Kingdom); Hammersmith Hospital, Robert Steiner MR Unit, MRC Clinical Sciences Centre, London (United Kingdom); Elorza, Leire Zubiaurre [Imperial College, Centre for the Developing Brain, London (United Kingdom); Hammersmith Hospital, Robert Steiner MR Unit, MRC Clinical Sciences Centre, London (United Kingdom); University of Barcelona, Department of Psychiatry and Clinical Psychobiology, Faculty of Medicine, Barcelona (Spain); Merchant, Nazakat; Arichi, Tomoki; Edwards, A.D.; Cowan, Frances M. [Imperial College, Centre for the Developing Brain, London (United Kingdom); Hammersmith Hospital, Robert Steiner MR Unit, MRC Clinical Sciences Centre, London (United Kingdom); Imperial College Healthcare NHS Trust, Division of Neonatology, London (United Kingdom); Porter, Emma [Imperial College Healthcare NHS Trust, Division of Neonatology, London (United Kingdom); Rutherford, Mary A. [Imperial College, Centre for the Developing Brain, London (United Kingdom); Imperial College Healthcare NHS Trust, Division of Neonatology, London (United Kingdom)

    2012-05-15

    Our aims were to (1) assess the corticospinal tracts (CSTs) in infants with focal injury and healthy term controls using probabilistic tractography and (2) to correlate the conventional magnetic resonance imaging (MRI) and tractography findings in infants with focal injury with their later motor function. We studied 20 infants with focal lesions and 23 controls using MRI and diffusion tensor imaging. Tract volume, fractional anisotropy (FA), apparent diffusion coefficient (ADC) values, axial diffusivity and radial diffusivity (RD) of the CSTs were determined. Asymmetry indices (AIs) were calculated by comparing ipsilateral to contralateral CSTs. Motor outcome was assessed using a standardized neurological examination. Conventional MRI was able to predict normal motor development (n = 9) or hemiplegia (n = 6). In children who developed a mild motor asymmetry (n = 5), conventional MRI predicted a hemiplegia in two and normal motor development in three infants. The AIs for tract volume, FA, ADC and RD showed a significant difference between controls and infants who developed a hemiplegia, and RD also showed a significant difference in AI between controls and infants who developed a mild asymmetry. Conventional MRI was able to predict subsequent normal motor development or hemiplegia following focal injury in newborn infants. Measures of RD obtained from diffusion tractography may offer additional information for predicting a subsequent asymmetry in motor function. (orig.)

  8. Quadri-Pulse Theta Burst Stimulation using Ultra-High Frequency Bursts - A New Protocol to Induce Changes in Cortico-Spinal Excitability in Human Motor Cortex

    DEFF Research Database (Denmark)

    Jung, Nikolai H; Gleich, Bernhard; Gattinger, Norbert;

    2016-01-01

    of sinusoidal TMS pulses elicited either a posterior-anterior (PA) or anterior-posterior (AP) directed current in M1. Motor evoked potentials (MEPs) were recorded before and after qTBS to probe changes in cortico-spinal excitability. PA-qTBS at 666 Hz caused a decrease in PA-MEP amplitudes, whereas AP...... in cortico-spinal excitability. Induced current direction in the brain appears to be relevant when qTBS targets I-wave periodicity, corroborating that high-fidelity spike timing mechanisms are critical for inducing bi-directional plasticity in human M1.......Patterned transcranial magnetic stimulation (TMS) such as theta burst stimulation (TBS) or quadri-pulse stimulation (QPS) can induce changes in cortico-spinal excitability, commonly referred to as long-term potentiation (LTP)-like and long-term depression (LTD)-like effects in human motor cortex (M...

  9. Role of sensory-motor cortex activity in postnatal development of corticospinal axon terminals in the cat.

    Science.gov (United States)

    Friel, Kathleen M; Martin, John H

    2005-04-25

    The initial pattern of corticospinal (CS) terminations, as axons grow into the spinal gray matter, bears little resemblance to the pattern later in development and in maturity. This is because of extensive axon pruning and local axon terminal growth during early postnatal development. Pruning is driven by activity-dependent competition between the CS systems on each side during postnatal weeks (PW) 3-7. It is not known whether CS axon terminal growth and final topography are activity dependent. We examined the activity dependence of CS axon terminal growth and topography at different postnatal times. We inactivated sensory-motor cortex by infusion of the gamma-aminobutyric acid type A (GABA(A)) agonist muscimol and traced CS axons from the inactivated side. Inactivation between PW5 and PW7 produced permanent changes in projection topography, reduced local axon branching, and prevented development of dense clusters of presynaptic sites, which are normally characteristic of CS terminals. Inactivation at younger (PW3-5) and older (PW8-12) ages did not affect projection topography but impeded development of local axon branching and presynaptic site clusters. These effects were not due to increased cortical cell death during inactivation. Neural activity plays an important role in determining the morphology of CS terminals during the entire period of development, but, for the projection topography, the role of activity is exercised during a very brief period. This points to a complex, and possibly independent, regulation of termination topography and terminal morphology. Surprisingly, when a CS neuron's activity is blocked during early development, it does not recover lost connections later in development once activity resumes.

  10. Long-term progressive motor skill training enhances corticospinal excitability for the ipsilateral hemisphere and motor performance of the untrained hand

    DEFF Research Database (Denmark)

    Christiansen, Lasse; Larsen, Malte Nejst; Grey, Michael James

    2017-01-01

    curve parameters following application of transcranial magnetic stimulation (TMS) to the ipsilateral primary motor cortex(iM1) hotspot of the left abductor digiti minimi muscle(ADM). PT led to significant improvements in left hand motor performance immediately after 6 weeks of training (63±18%,P...It is well-established that unilateral motor practice can lead to increased performance in the opposite non-trained hand. Here, we test the hypothesis that progressively increasing task difficulty during long-term skill training with the dominant right hand increase performance and corticomotor...... excitability of the left non-trained hand. Subjects practiced a visuomotor tracking task engaging right digit V for 6 weeks with either progressively increasing task difficulty (PT) or no progression (NPT). Corticospinal excitability(CSE) was evaluated from the resting motor threshold(rMT) and recruitment...

  11. Functional corticospinal projections from human supplementary motor area revealed by corticomuscular coherence during precise grip force control.

    Directory of Open Access Journals (Sweden)

    Sophie Chen

    Full Text Available The purpose of the present study was to investigate whether corticospinal projections from human supplementary motor area (SMA are functional during precise force control with the precision grip (thumb-index opposition. Since beta band corticomuscular coherence (CMC is well-accepted to reflect efferent corticospinal transmission, we analyzed the beta band CMC obtained with simultaneous recording of electroencephalographic (EEG and electromyographic (EMG signals. Subjects performed a bimanual precise visuomotor force tracking task by applying isometric low grip forces with their right hand precision grip on a custom device with strain gauges. Concurrently, they held the device with their left hand precision grip, producing similar grip forces but without any precision constraints, to relieve the right hand. Some subjects also participated in a unimanual control condition in which they performed the task with only the right hand precision grip while the device was held by a mechanical grip. We analyzed whole scalp topographies of beta band CMC between 64 EEG channels and 4 EMG intrinsic hand muscles, 2 for each hand. To compare the different topographies, we performed non-parametric statistical tests based on spatio-spectral clustering. For the right hand, we obtained significant beta band CMC over the contralateral M1 region as well as over the SMA region during static force contraction periods. For the left hand, however, beta band CMC was only found over the contralateral M1. By comparing unimanual and bimanual conditions for right hand muscles, no significant difference was found on beta band CMC over M1 and SMA. We conclude that the beta band CMC found over SMA for right hand muscles results from the precision constraints and not from the bimanual aspect of the task. The result of the present study strongly suggests that the corticospinal projections from human SMA become functional when high precision force control is required.

  12. A change in injured corticospinal tract originating from the premotor cortex to the primary motor cortex in a patient with intracerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    Sang Seok Yeo; Sung Ho Jang

    2012-01-01

    Many studies have attempted to elucidate the motor recovery mechanism of stroke, but the majority of these studies focus on cerebral infarct and relatively little is known about the motor recovery mechanism of intracerebral hemorrhage. In this study, we report on a patient with intracerebral hemorrhage who displayed a change in injured corticospinal tract originating from the premotor cortex to the primary motor cortex on diffusion tensor imaging. An 86-year-old woman presented with complete paralysis of the right extremities following spontaneous intracerebral hemorrhage in the left frontoparietal cortex. The patient showed motor recovery, to the extent of being able to extend affected fingers against gravity and to walk independently on even ground at 5 months after onset. Diffusion tensor imaging showed that the left corticospinal tract originated from the premotor cortex at 1 month after intracerebral hemorrhage and from the left primary motor cortex and premotor cortex at 5 months after intracerebral hemorrhage. The change of injured corticospinal tract originating from the premotor cortex to the primary motor cortex suggests motor recovery of intracerebral hemorrhage.

  13. Facilitation of corticospinal excitability according to motor imagery and mirror therapy in healthy subjects and stroke patients.

    Science.gov (United States)

    Kang, Youn Joo; Ku, Jeonghun; Kim, Hyun Jung; Park, Hae Kyung

    2011-12-01

    To delineate the changes in corticospinal excitability when individuals are asked to exercise their hand using observation, motor imagery, voluntary exercise, and exercise with a mirror. The participants consisted of 30 healthy subjects and 30 stroke patients. In healthy subjects, the amplitudes and latencies of motor evoked potential (MEP) were obtained using seven conditions: (A) rest; (B) imagery; (C) observation and imagery of the hand activity of other individuals; (D) observation and imagery of own ipsilateral hand activity; (E) observation and imagery of the hand activity of another individual with a mirror; (F) observation and imagery of own symmetric ipsilateral hand activity (thumb abduction) with a mirror; and (G) observation and imagery of own asymmetric ipsilateral hand activity (little finger abduction) with a mirror. In stroke patients, MEPs were obtained in the A, C, D, E, F conditions. In both groups, increment of the percentage MEP amplitude (at rest) and latency decrement of MEPs were significantly higher during the observation of the activity of the hand of another individual with a mirror and during symmetric ipsilateral hand activity on their own hand with a mirror than they were without a mirror. In healthy subjects, the increment of percentage MEP amplitude and latency decrement were significantly higher during the observation of the symmetric ipsilateral hand activity with a mirror compared to the observation of the activity of the asymmetric ipsilateral hand with a mirror of their own hand. In both groups, corticospinal excitability was facilitated by viewing the mirror image of the activity of the ipsilateral hand. These findings provide neurophysiological evidence supporting the application of various mirror imagery programs during stroke rehabilitation.

  14. Identification of the primary motor area by three-dimensional reconstruction of the corticospinal tract using diffusion tensor imaging

    Institute of Scientific and Technical Information of China (English)

    Guojun Deng; Luo Li; Guimei Chen; Erming Zeng; Xiangzuo Xiao; Meihua Li; Tao Hong; Donghai Li

    2011-01-01

    Functional MRI (fMRI) is widely used as a non-invasive method for the evaluation of pre-operation motor function. However, patients with cortical function impairment, such as those with hemiparesis, can rarely achieve hand clenching, a typical fMRI task for central sulcus identification, and the method is also of limited use in uncooperative children. Thus, it is important to develop a new method for identifying primary motor areas (PMA) in such individuals. This study used corticospinal tractography to identify the PMA in 20 patients with deep-seated brain tumor. Two regions of interest were set within the brainstem for corticospinal tract (CST) fiber tracking: one at the level of the pons and the other at the level of the cerebral peduncle. The CST fiber tracking results and fMRI activation signals were merged with three-dimensional anatomic MRI findings. The consistency of identifying the PMA by CST and fMRI was analyzed. fMRI activation signals were distributed mainly in the contralateral central sulcus around the omega-shaped hand knob. The CST consistently propagated from the pons and cerebral peduncle to the suspected PMA location. There was a good correlation between CST fiber tracking results and fMRI activation signals in terms of their abilities to identify the PMA. The differences between fMRI and CST fiber tracking findings may result from our functional task, which consisted only of hand movements. Our results indicate that diffusion tensor imaging is a useful brain mapping technique for identifying the PMA in paralyzed patients and uncooperative children.

  15. Change in Excitability of Corticospinal Pathway and GABA-Mediated Inhibitory Circuits of Primary Motor Cortex Induced by Contraction of Adjacent Hand Muscle.

    Science.gov (United States)

    Jono, Yasutomo; Iwata, Yasuyuki; Mizusawa, Hiroki; Hiraoka, Koichi

    2016-11-01

    The present study examined whether the excitability of the corticospinal pathway and the GABA-mediated inhibitory circuits of the primary motor cortex that project onto the corticospinal neurons in the tonically contracting hand muscle are changed by tonic contraction of the adjacent hand muscle. The motor evoked potential (MEP) and cortical silent period (CSP) in the tonically contracting hand muscle were obtained while the adjacent hand muscle was either tonically contracting or at rest. The MEP and CSP of the first dorsal interosseous (FDI) muscle elicited across the scalp sites where the MEP is predominantly elicited in the FDI muscle were decreased by tonic contraction of the abductor digiti minimi (ADM) muscle. The centers of the area of the MEP and the duration of the CSP in the FDI muscle elicited across the sites where the MEP is predominantly elicited in the FDI muscle were lateral to those in the FDI muscle elicited across the sites where the MEP is elicited in both the FDI and ADM muscles. They were also lateral to those in the ADM muscle elicited either across the sites where the MEP is predominantly elicited in the ADM muscle, or across the sites where the MEP is elicited in both the FDI and ADM muscles. The decrease in the corticospinal excitability and the excitability of the GABA-mediated inhibitory circuits of the primary motor cortex that project onto the corticospinal neurons in the FDI muscle may be due either to (1) the interaction between the activity of the lateral area of the FDI representation and the descending drive to the ADM muscle, or (2) the decreased susceptibility of the primary motor area that predominantly projects onto the corticospinal neurons in the FDI muscle, which also plays a role in independent finger movement when both the FDI and ADM muscles act together as synergists.

  16. Corticospinal excitability during observation and imagery of simple and complex hand tasks : Implications for motor rehabilitation

    NARCIS (Netherlands)

    Roosink, Meyke; Zijdewind, Inge

    2010-01-01

    Movement observation and imagery are increasingly propagandized for motor rehabilitation. Both observation and imagery are thought to improve motor function through repeated activation of mental motor representations. However, it is unknown what stimulation parameters or imagery conditions are optim

  17. Corticospinal excitability during observation and imagery of simple and complex hand tasks : Implications for motor rehabilitation

    NARCIS (Netherlands)

    Roosink, Meyke; Zijdewind, Inge

    2010-01-01

    Movement observation and imagery are increasingly propagandized for motor rehabilitation. Both observation and imagery are thought to improve motor function through repeated activation of mental motor representations. However, it is unknown what stimulation parameters or imagery conditions are

  18. Exercise promotes motor functional recovery in rats with corticospinal tract injury: anti-apoptosis mechanism

    Directory of Open Access Journals (Sweden)

    Ting-ting Hou

    2015-01-01

    Full Text Available Studies have shown that exercise interventions can improve functional recovery after spinal cord injury, but the mechanism of action remains unclear. To investigate the mechanism, we established a unilateral corticospinal tract injury model in rats by pyramidotomy, and used a single pellet reaching task and horizontal ladder walking task as exercise interventions postoperatively. Functional recovery of forelimbs and forepaws in the rat models was noticeably enhanced after the exercises. Furthermore, TUNEL staining revealed significantly fewer apoptotic cells in the spinal cord of exercised rats, and western blot analysis showed that spinal cord expression of the apoptosis-related protein caspase-3 was significantly lower, and the expression of Bcl-2 was significantly higher, while the expression of Bax was not signifiantly changed after exercise, compared with the non-exercised group. Expression of these proteins decreased with time after injury, towards the levels observed in sham-operated rats, however at 4 weeks postoperatively, caspase-3 expression remained significantly greater than in sham-operated rats. The present findings indicate that a reduction in apoptosis is one of the mechanisms underlying the improvement of functional recovery by exercise interventions after corticospinal tract injury.

  19. Quadri-Pulse Theta Burst Stimulation using Ultra-High Frequency Bursts - A New Protocol to Induce Changes in Cortico-Spinal Excitability in Human Motor Cortex.

    Science.gov (United States)

    Jung, Nikolai H; Gleich, Bernhard; Gattinger, Norbert; Hoess, Catrina; Haug, Carolin; Siebner, Hartwig R; Mall, Volker

    2016-01-01

    Patterned transcranial magnetic stimulation (TMS) such as theta burst stimulation (TBS) or quadri-pulse stimulation (QPS) can induce changes in cortico-spinal excitability, commonly referred to as long-term potentiation (LTP)-like and long-term depression (LTD)-like effects in human motor cortex (M1). Here, we aimed to test the plasticity-inducing capabilities of a novel protocol that merged TBS and QPS. 360 bursts of quadri-pulse TBS (qTBS) were continuously given to M1 at 90% of active motor threshold (1440 full-sine pulses). In a first experiment, stimulation frequency of each burst was set to 666 Hz to mimic the rhythmicity of the descending cortico-spinal volleys that are elicited by TMS (i.e., I-wave periodicity). In a second experiment, burst frequency was set to 200 Hz to maximize postsynaptic Ca2+ influx using a temporal pattern unrelated to I-wave periodicity. The second phase of sinusoidal TMS pulses elicited either a posterior-anterior (PA) or anterior-posterior (AP) directed current in M1. Motor evoked potentials (MEPs) were recorded before and after qTBS to probe changes in cortico-spinal excitability. PA-qTBS at 666 Hz caused a decrease in PA-MEP amplitudes, whereas AP-qTBS at 666 Hz induced an increase in mean AP-MEP amplitudes. At a burst frequency of 200 Hz, PA-qTBS and AP-qTBS produced an increase in cortico-spinal excitability outlasting for at least 60 minutes in PA- and AP-MEP amplitudes, respectively. Continuous qTBS at 666 Hz or 200 Hz can induce lasting changes in cortico-spinal excitability. Induced current direction in the brain appears to be relevant when qTBS targets I-wave periodicity, corroborating that high-fidelity spike timing mechanisms are critical for inducing bi-directional plasticity in human M1.

  20. Direct mapping rather than motor prediction subserves modulation of corticospinal excitability during observation of actions in real time.

    Science.gov (United States)

    Gueugneau, Nicolas; Mc Cabe, Sofia I; Villalta, Jorge I; Grafton, Scott T; Della-Maggiore, Valeria

    2015-06-01

    Motor facilitation refers to the specific increment in corticospinal excitability (CSE) elicited by the observation of actions performed by others. To date, the precise nature of the mechanism at the basis of this phenomenon is unknown. One possibility is that motor facilitation is driven by a predictive process reminiscent of the role of forward models in motor control. Alternatively, motor facilitation may result from a model-free mechanism by which the basic elements of the observed action are directly mapped onto their cortical representations. Our study was designed to discern these alternatives. To this aim, we recorded the time course of CSE for the first dorsal interosseous (FDI) and the abductor digiti minimi (ADM) during observation of three grasping actions in real time, two of which strongly diverged in kinematics from their natural (invariant) form. Although artificially slow movements used in most action observation studies might enhance the observer's discrimination performance, the use of videos in real time is crucial to maintain the time course of CSE within the physiological range of daily actions. CSE was measured at 4 time points within a 240-ms window that best captured the kinematic divergence from the invariant form. Our results show that CSE of the FDI, not the ADM, closely follows the functional role of the muscle despite the mismatch between the natural and the divergent kinematics. We propose that motor facilitation during observation of actions performed in real time reflects the model-free coding of perceived movement following a direct mapping mechanism. Copyright © 2015 the American Physiological Society.

  1. Motor cortex electrical stimulation promotes axon outgrowth to brain stem and spinal targets that control the forelimb impaired by unilateral corticospinal injury.

    Science.gov (United States)

    Carmel, Jason B; Kimura, Hiroki; Berrol, Lauren J; Martin, John H

    2013-04-01

    We previously showed that electrical stimulation of motor cortex (M1) after unilateral pyramidotomy in the rat increased corticospinal tract (CST) axon length, strengthened spinal connections, and restored forelimb function. Here, we tested: (i) if M1 stimulation only increases spinal axon length or if it also promotes connections to brain stem forelimb control centers, especially magnocellular red nucleus; and (ii) if stimulation-induced increase in axon length depends on whether pyramidotomy denervated the structure. After unilateral pyramidotomy, we electrically stimulated the forelimb area of intact M1, to activate the intact CST and other corticofugal pathways, for 10 days. We anterogradely labeled stimulated M1 and measured axon length using stereology. Stimulation increased axon length in both the spinal cord and magnocellular red nucleus, even though the spinal cord is denervated by pyramidotomy and the red nucleus is not. Stimulation also promoted outgrowth in the cuneate and parvocellular red nuclei. In the spinal cord, electrical stimulation caused increased axon length ipsilateral, but not contralateral, to stimulation. Thus, stimulation promoted outgrowth preferentially to the sparsely corticospinal-innervated and impaired side. Outgrowth resulted in greater axon density in the ipsilateral dorsal horn and intermediate zone, resembling the contralateral termination pattern. Importantly, as in spinal cord, increase in axon length in brain stem also was preferentially directed towards areas less densely innervated by the stimulated system. Thus, M1 electrical stimulation promotes increases in corticofugal axon length to multiple M1 targets. We propose the axon length change was driven by competition into an adaptive pattern resembling lost connections. © 2013 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  2. Motor-evoked potential gain is a helpful test for the detection of corticospinal tract dysfunction in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Duclos, Y; Grapperon, A M; Jouve, E; Truillet, R; Zemmour, C; Verschueren, A; Pouget, J; Attarian, S

    2017-02-01

    The detection of upper motor neuron (UMN) dysfunction is necessary for the diagnosis of amyotrophic lateral sclerosis (ALS). However, signs of UMN dysfunction may be difficult to establish. This study aimed to determine whether motor-evoked potential (MEP) gain (MEP area/background electromyographic activity) represents an efficient alternative to assess UMN dysfunction. MEP area, MEP/compound muscle action potential (CMAP) area ratio, and MEP gain were tested at different force levels in healthy control subjects and ALS patients. Receiver operating characteristic (ROC) curve analyses was used to determine the diagnostic utility of MEP gain and compare it to alternative techniques, namely, diffusion tensor imaging (DTI) and the triple stimulation technique (TST). MEP gain revealed a significant difference between the patients and healthy control subjects in contrast to MEP area and MEP/CMAP area ratio. The diagnostic utility of MEP gain was comparable with that of TST and superior to that of DTI. MEP gain can distinguish ALS patients from control subjects and may be helpful for the diagnosis of ALS. MEP gain appears to be a useful adjunct test and noninvasive method for the assessment of corticospinal dysfunction. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  3. Retrograde labeling, transduction and genetic targeting allow cellular analysis of corticospinal motor neurons: Implications in health and disease.

    Directory of Open Access Journals (Sweden)

    Javier Hernan Jara

    2014-03-01

    Full Text Available Corticospinal motor neurons (CSMN have a unique ability to receive, integrate, translate, and transmit the cerebral cortex’s input toward spinal cord targets and therefore, act as a spokesperson for the initiation and modulation of voluntary movements that require cortical input. CSMN degeneration has an immense impact on motor neuron circuitry and is one of the underlying causes of numerous neurodegenerative diseases, such as primary lateral sclerosis, hereditary spastic paraplegia, and amyotrophic lateral sclerosis. In addition, CSMN death results in long-term paralysis in spinal cord injury patients. Detailed cellular analyses are crucial to gain a better understanding of the pathologies underlying CSMN degeneration. However, visualizing and identifying these vulnerable neuron populations in the complex and heterogeneous environment of the cerebral cortex has proved challenging. Here, we will review recent developments and current applications of novel strategies that reveal the cellular and molecular basis of CSMN health and vulnerability. Such studies hold promise for building long-term effective treatment solutions in the near future.

  4. Harnessing neural activity to promote repair of the damaged corticospinal system after spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    John H. Martin

    2016-01-01

    As most spinal cord injuries (SCIs) are incomplete, an important target for promoting neural repair and recovery of lost motor function is to promote the connections of spared descending spinal pathways with spinal motor circuits. Among the pathways, the corticospinal tract (CST) is most associated with skilled voluntary functions in humans and many animals. CST loss, whether at its origin in the motor cortex or in the white matter tracts subcortically and in the spinal cord, leads to movement impairments and paraly-sis. To restore motor function after injury will require repair of the damaged CST. In this review, I discuss how knowledge of activity-dependent development of the CST—which establishes connectional speci-ifcity through axon pruning, axon outgrowth, and synaptic competition among CST terminals—informed a novel activity-based therapy for promoting sprouting of spared CST axons after injur in mature animals. This therapy, which comprises motor cortex electrical stimulation with and without concurrent trans-spi-nal direct current stimulation, leads to an increase in the gray matter axon length of spared CST axons in the rat spinal cord and, after a pyramidal tract lesion, restoration of skilled locomotor movements. I discuss how this approach is now being applied to a C4 contusion rat model.

  5. Harnessing neural activity to promote repair of the damaged corticospinal system after spinal cord injury

    Directory of Open Access Journals (Sweden)

    John H Martin

    2016-01-01

    Full Text Available As most spinal cord injuries (SCIs are incomplete, an important target for promoting neural repair and recovery of lost motor function is to promote the connections of spared descending spinal pathways with spinal motor circuits. Among the pathways, the corticospinal tract (CST is most associated with skilled voluntary functions in humans and many animals. CST loss, whether at its origin in the motor cortex or in the white matter tracts subcortically and in the spinal cord, leads to movement impairments and paralysis. To restore motor function after injury will require repair of the damaged CST. In this review, I discuss how knowledge of activity-dependent development of the CST-which establishes connectional specificity through axon pruning, axon outgrowth, and synaptic competition among CST terminals-informed a novel activity-based therapy for promoting sprouting of spared CST axons after injur in mature animals. This therapy, which comprises motor cortex electrical stimulation with and without concurrent trans-spinal direct current stimulation, leads to an increase in the gray matter axon length of spared CST axons in the rat spinal cord and, after a pyramidal tract lesion, restoration of skilled locomotor movements. I discuss how this approach is now being applied to a C 4 contusion rat model.

  6. Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function.

    Science.gov (United States)

    Thibaut, Aurore; Simis, Marcel; Battistella, Linamara Rizzo; Fanciullacci, Chiara; Bertolucci, Federica; Huerta-Gutierrez, Rodrigo; Chisari, Carmelo; Fregni, Felipe

    2017-01-01

    What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (transcranial magnetic stimulation-TMS) and brain oscillations (electroencephalography-EEG). In this cross-sectional study, 55 subjects with chronic stroke (62 ± 14 yo, 17 women, 32 ± 42 months post-stroke) were recruited in two sites. We analyzed TMS measures (i.e., motor threshold-MT-of the affected and unaffected sides) and EEG variables (i.e., power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres) and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high-frequency rhythms and motor impairment, highlighting the role of an excess of beta in the affected central cortical region in poor motor function in stroke recovery.

  7. Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function

    Directory of Open Access Journals (Sweden)

    Aurore Thibaut

    2017-05-01

    Full Text Available What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (transcranial magnetic stimulation—TMS and brain oscillations (electroencephalography—EEG. In this cross-sectional study, 55 subjects with chronic stroke (62 ± 14 yo, 17 women, 32 ± 42 months post-stroke were recruited in two sites. We analyzed TMS measures (i.e., motor threshold—MT—of the affected and unaffected sides and EEG variables (i.e., power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high-frequency rhythms and motor impairment, highlighting the role of an excess of beta in the affected central cortical region in poor motor function in stroke recovery.

  8. Computer-assisted three-dimensional reconstruction of the corticospinal system as a reference for CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Buhmann, C. [Department of Neuroanatomy, Hannover Medical School (Germany)]|[University Hospital Eppendorf, Hamburg (Germany); Kretschmann, H.J. [Department of Neuroanatomy, Hannover Medical School (Germany)

    1998-09-01

    We present a three-dimensional (3D) anatomical computer-graphics model of the corticospinal system acquired from equidistant serial anatomical slices of six intracranially-fixed human brains. This model is part of a neuroanatomical reference system (NeuRef) which enables 3D visualization of the brain and shows the relationship of its components such as anatomical structures, functional fibre tracts and arteries. Sections through the models can be matched with corresponding CT or MR images. This allows the probable localisation of corticospinal fibres on CT or MRI. (orig.) (orig.) With 18 figs., 3 tabs., 40 refs.

  9. Right lower limb apraxia in a patient with left supplementary motor area infarction: intactness of the corticospinal tract confirmed by transcranial magnetic stimulation

    Directory of Open Access Journals (Sweden)

    Min Cheol Chang

    2015-01-01

    Full Text Available We reported a 50-year-old female patient with left supplementary motor area infarction who presented right lower limb apraxia and investigated the possible causes using transcranial magnetic stimulation. The patient was able to walk and climb stairs spontaneously without any assistance at 3 weeks after onset. However, she was unable to intentionally move her right lower limb although she understood what she supposed to do. The motor evoked potential evoked by transcranial magnetic stimulation from the right lower limb was within the normal range, indicating that the corticospinal tract innervating the right lower limb was uninjured. Thus, we thought that her motor dysfunction was not induced by motor weakness, and confirmed her symptoms as apraxia. In addition, these results also suggest that transcranial magnetic stimulation is helpful for diagnosing apraxia.

  10. Behavioural and neurophysiological disruption of corticobulbar motor systems and their effects on sequential pharyngeal swallowing.

    Science.gov (United States)

    Al-Toubi, Aamir; Daniels, Stephanie K; Huckabee, Maggie-Lee; Corey, David M; Doeltgen, Sebastian H

    2016-10-15

    Primary motor networks are known to be involved in the control of voluntary oral movements as well as the modulation of pharyngeal movements during experimentally controlled single swallows performed on command. The role of these networks in the more typical task of sequential swallowing remains unexplored. This study evaluated the hypothesis that experimental disruption of motor cortical activation would reduce the rate and regularity of repeatedly performed volitional or volitionally initiated motor tasks controlled by corticospinal (finger tapping) and corticobulbar (eyebrow movement, jaw opening, volitional sequential swallowing) motor systems, but would not influence a more reflexive corticobulbar task (reflexive sequential swallowing to pharyngeal water infusion). This premise was investigated in 24 healthy participants using two techniques: a dual task paradigm and a transcranial magnetic stimulation paradigm. Disruption effects were quantified by changes in rate and regularity of performance for each tested motor task. In summary, volitional motor tasks controlled by corticospinal motor networks (finger tapping) are more susceptible to behavioural and neurophysiological disruption than tasks controlled by cortiobulbar motor networks containing a reflexive component (both volitional and experimentally initiated consecutive swallowing). Purely volitional motor tasks controlled by the corticobulbar motor system (eyebrow raising or jaw opening) were affected in similar ways as the volitional corticospinal motor tasks. In summary, tasks involving sequential pharyngeal swallowing - whether volitionally or experimentally initiated - are largely robust against disruption of primary cortical motor networks, supporting a key role of medullary CPGs in the motor control of sequential pharyngeal swallowing.

  11. Reversed Effects of Intermittent Theta Burst Stimulation following Motor Training That Vary as a Function of Training-Induced Changes in Corticospinal Excitability

    Directory of Open Access Journals (Sweden)

    Tino Stöckel

    2015-01-01

    Full Text Available Intermittent theta burst stimulation (iTBS has the potential to enhance corticospinal excitability (CSE and subsequent motor learning. However, the effects of iTBS following motor learning are unknown. The purpose of the present study was to explore the effect of iTBS on CSE and performance following motor learning. Therefore twenty-four healthy participants practiced a ballistic motor task for a total of 150 movements. iTBS was subsequently applied to the trained motor cortex (STIM group or the vertex (SHAM group. Performance and CSE were assessed before motor learning and before and after iTBS. Training significantly increased performance and CSE in both groups. In STIM group participants, subsequent iTBS significantly reduced motor performance with smaller reductions in CSE. CSE changes as a result of motor learning were negatively correlated with both the CSE changes and performance changes as a result of iTBS. No significant effects of iTBS were found for SHAM group participants. We conclude that iTBS has the potential to degrade prior motor learning as a function of training-induced CSE changes. That means the expected LTP-like effects of iTBS are reversed following motor learning.

  12. Motor recovery in a patient with an infarct in the medullary pyramid via the corticospinal tract passing through the small spared area within the infarcted medullary pyramid

    Institute of Scientific and Technical Information of China (English)

    Hyeok Gyu Kwon; Sung Ho Jang

    2011-01-01

    The present study reported a 58-year-old male patient who exhibited complete paralysis of the right extremities at stroke onset.Brain MR images showed an infarct in the left medullary pyramid and a small spared area on the medial side of the infarct.He gained the ability to extend the affected fingers against gravity and to dorsiflex the affected ankle without gravity at 3 months after stroke onset.Diffusion tensor imaging results showed that at 6 months after stroke onset,the corticospinal tract of the affected (left) hemisphere descended through the small spared area of the infarcted medullary pyramid.No motor-evoked potential was elicited from the affected (left) hemisphere at 2 weeks after stroke onset;however,motor-evoked potential was elicited at 6 months as shown by transcranial magnetic stimulation results.The motor function of the affected side of this patient appears to have been recovered via the corticospinal tract that passed through the small spared area within the infarcted medullary pyramid.

  13. Do not resonate with actions: sentence polarity modulates cortico-spinal excitability during action-related sentence reading.

    Directory of Open Access Journals (Sweden)

    Marco Tullio Liuzza

    Full Text Available BACKGROUND: Theories of embodied language suggest that the motor system is differentially called into action when processing motor-related versus abstract content words or sentences. It has been recently shown that processing negative polarity action-related sentences modulates neural activity of premotor and motor cortices. METHODS AND FINDINGS: We sought to determine whether reading negative polarity sentences brought about differential modulation of cortico-spinal motor excitability depending on processing hand-action related or abstract sentences. Facilitatory paired-pulses Transcranial Magnetic Stimulation (pp-TMS was applied to the primary motor representation of the right-hand and the recorded amplitude of induced motor-evoked potentials (MEP was used to index M1 activity during passive reading of either hand-action related or abstract content sentences presented in both negative and affirmative polarity. Results showed that the cortico-spinal excitability was affected by sentence polarity only in the hand-action related condition. Indeed, in keeping with previous TMS studies, reading positive polarity, hand action-related sentences suppressed cortico-spinal reactivity. This effect was absent when reading hand action-related negative polarity sentences. Moreover, no modulation of cortico-spinal reactivity was associated with either negative or positive polarity abstract sentences. CONCLUSIONS: Our results indicate that grammatical cues prompting motor negation reduce the cortico-spinal suppression associated with affirmative action sentences reading and thus suggest that motor simulative processes underlying the embodiment may involve even syntactic features of language.

  14. Biotinylated dextran amine anterograde tracing of the canine corticospinal tract

    Institute of Scientific and Technical Information of China (English)

    Xiao Han; Guangming Lv; Huiqun Wu; Dafeng Ji; Zhou Sun; Yaofu Li; Lemin Tang

    2012-01-01

    In this study, biotinylated dextran amine (BDA) was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were visible in the left cortical motor area after injection. In the left medulla oblongata, the BDA-labeled corticospinal tract was evenly distributed, with green fluorescence that had a clear boundary with the surrounding tissue. The BDA-positive corticospinal tract entered into the right lateral funiculus of the spinal cord and descended into the posterior part of the right lateral funiculus, close to the posterior horn, from cervical to sacral segments. There was a small amount of green fluorescence in the sacral segment. The distribution of BDA labeling in the canine central nervous system was consistent with the course of the corticospinal tract. Fluorescence labeling for BDA gradually diminished with time after injection. Our findings indicate that the BDA anterograde tracing technique can be used to visualize the localization and trajectory of the corticospinal tract in the canine central nervous system.

  15. Early changes in corticospinal excitability when seeing fearful body expressions.

    Science.gov (United States)

    Borgomaneri, Sara; Vitale, Francesca; Avenanti, Alessio

    2015-09-21

    Quick inhibition of approach tendencies in response to signals of potential threats is thought to promote survival. However, little is known about the effect of viewing fearful expressions on the early dynamics of the human motor system. We used the high temporal resolution of single-pulse and paired-pulse transcranial magnetic stimulation (TMS) over the motor cortex to assess corticospinal excitability (CSE) and intracortical facilitation (ICF) during observation of happy, fearful and neutral body postures. To test motor circuits involved in approach tendencies, CSE and ICF were recorded from the first dorsal interosseous (FDI), a muscle involved in grasping, and the abductor pollicis brevis (APB), which served as a control. To test early motor dynamics, CSE and ICF were measured 70-90 ms after stimulus onset. We found a selective reduction in CSE in the FDI when participants observed fearful body expressions. No changes in ICF or in the excitability of APB were detected. Our study establishes an extremely rapid motor system reaction to observed fearful body expressions. This motor modulation involves corticospinal downstream projections but not cortical excitatory mechanisms, and appears to reflect an inhibition of hand grasping. Our results suggest a fast visuo-motor route that may rapidly inhibit inappropriate approaching actions.

  16. Processing abstract language modulates motor system activity.

    Science.gov (United States)

    Glenberg, Arthur M; Sato, Marc; Cattaneo, Luigi; Riggio, Lucia; Palumbo, Daniele; Buccino, Giovanni

    2008-06-01

    Embodiment theory proposes that neural systems for perception and action are also engaged during language comprehension. Previous neuroimaging and neurophysiological studies have only been able to demonstrate modulation of action systems during comprehension of concrete language. We provide neurophysiological evidence for modulation of motor system activity during the comprehension of both concrete and abstract language. In Experiment 1, when the described direction of object transfer or information transfer (e.g., away from the reader to another) matched the literal direction of a hand movement used to make a response, speed of responding was faster than when the two directions mismatched (an action-sentence compatibility effect). In Experiment 2, we used single-pulse transcranial magnetic stimulation to study changes in the corticospinal motor pathways to hand muscles while reading the same sentences. Relative to sentences that do not describe transfer, there is greater modulation of activity in the hand muscles when reading sentences describing transfer of both concrete objects and abstract information. These findings are discussed in relation to the human mirror neuron system.

  17. Step Motor Control System

    Institute of Scientific and Technical Information of China (English)

    ZhangShuochengt; WangDan; QiaoWeimin; JingLan

    2003-01-01

    All kinds of step motors and servomotors are widely used in CSR control system, such as many vacuum valves control that set on the HIRFL-CSR; all kinds of electric switches and knobs of ECR Ion Source; equipment of CSR Beam Diagnostics and a lot of large equipment like Inside Gun Toroid and Collector Toroid of HIRFL. A typical control system include up to 32 16-I/O Control boards, and each 16-I/O Control board can control 4 motors at the same time (including 8 Limit Switches).

  18. Corticospinal state variability and hemispheric asymmetries in motivational tendencies

    NARCIS (Netherlands)

    Schutter, D.J.L.G.; Hofman, D.; Hoppenbrouwers, S.S.; Kenemans, J.L.

    2011-01-01

    This transcranial magnetic stimulation (TMS) study examined interrelations between asymmetrical hemispheric differences in the degree of variability of corticospinal excitability levels and motivational tendencies. The relative standard deviation in motor evoked potentials (MEP) to single pulse TMS

  19. Paired-Pulse Parietal-Motor Stimulation Differentially Modulates Corticospinal Excitability across Hemispheres When Combined with Prism Adaptation.

    Science.gov (United States)

    Schintu, Selene; Martín-Arévalo, Elisa; Vesia, Michael; Rossetti, Yves; Salemme, Romeo; Pisella, Laure; Farnè, Alessandro; Reilly, Karen T

    2016-01-01

    Rightward prism adaptation ameliorates neglect symptoms while leftward prism adaptation (LPA) induces neglect-like biases in healthy individuals. Similarly, inhibitory repetitive transcranial magnetic stimulation (rTMS) on the right posterior parietal cortex (PPC) induces neglect-like behavior, whereas on the left PPC it ameliorates neglect symptoms and normalizes hyperexcitability of left hemisphere parietal-motor (PPC-M1) connectivity. Based on this analogy we hypothesized that LPA increases PPC-M1 excitability in the left hemisphere and decreases it in the right one. In an attempt to shed some light on the mechanisms underlying LPA's effects on cognition, we investigated this hypothesis in healthy individuals measuring PPC-M1 excitability with dual-site paired-pulse TMS (ppTMS). We found a left hemisphere increase and a right hemisphere decrease in the amplitude of motor evoked potentials elicited by paired as well as single pulses on M1. While this could indicate that LPA biases interhemispheric connectivity, it contradicts previous evidence that M1-only MEPs are unchanged after LPA. A control experiment showed that input-output curves were not affected by LPA per se. We conclude that LPA combined with ppTMS on PPC-M1 differentially alters the excitability of the left and right M1.

  20. Visualization of the eloquent motor system by integration of MEG, functional, and anisotropic diffusion-weighted MRI in functional neuronavigation.

    Science.gov (United States)

    Kamada, Kyousuke; Houkin, Kiyohiro; Takeuchi, Fumiya; Ishii, Nobuaki; Ikeda, Jun; Sawamura, Yutaka; Kuriki, Shinya; Kawaguchi, Hideaki; Iwasaki, Yoshinobu

    2003-05-01

    In this study, we visualized the eloquent motor system including the somatosensory-motor cortex and corticospinal tract on a neuronavigation system, integrating magnetoencephalography (MEG), functional magnetic resonance imaging (fMRI), and anisotropic diffusion-weighted MRI (ADWI). Four patients with brain lesions adjacent to the eloquent motor system were studied. Motor-evoked responses (MER) by finger-tapping paradigm were acquired with a 1.5-Tesla MR scanner, and somatosensory-evoked magnetic fields (SEF) by median nerve stimulation were measured with a 204-channel MEG system. In the same fMRI examination, ADWI and anatomic three-dimensional T1-weighted imaging (3-D MRI) were obtained. Activated areas of MER, estimated SEF dipoles, and the corticospinal tract on ADWI were coregistered to 3-D MRI, and the combined MR data were transferred to a neuronavigation system (functional neuronavigation). Intraoperative recording of cortical somatosensory-evoked potentials was performed for confirmation of the central sulcus. Combination of fMRI and MEG enabled firm identification of the central sulcus. Functional neuronavigation facilitated extensive tumor resection, having the advantage of sparing the motor cortex and corticospinal tract in all cases. The proposed functional neuronavigation allows neurosurgeons to perform effective and maximal resection of brain lesions, identifying and sparing eloquent cortical components and their subcortical connections. Potential clinical application of this technique is discussed.

  1. Distinct olfactory cross-modal effects on the human motor system.

    Directory of Open Access Journals (Sweden)

    Simone Rossi

    Full Text Available BACKGROUND: Converging evidence indicates that action observation and action-related sounds activate cross-modally the human motor system. Since olfaction, the most ancestral sense, may have behavioural consequences on human activities, we causally investigated by transcranial magnetic stimulation (TMS whether food odour could additionally facilitate the human motor system during the observation of grasping objects with alimentary valence, and the degree of specificity of these effects. METHODOLOGY/PRINCIPAL FINDINGS: In a repeated-measure block design, carried out on 24 healthy individuals participating to three different experiments, we show that sniffing alimentary odorants immediately increases the motor potentials evoked in hand muscles by TMS of the motor cortex. This effect was odorant-specific and was absent when subjects were presented with odorants including a potentially noxious trigeminal component. The smell-induced corticospinal facilitation of hand muscles during observation of grasping was an additive effect which superimposed to that induced by the mere observation of grasping actions for food or non-food objects. The odour-induced motor facilitation took place only in case of congruence between the sniffed odour and the observed grasped food, and specifically involved the muscle acting as prime mover for hand/fingers shaping in the observed action. CONCLUSIONS/SIGNIFICANCE: Complex olfactory cross-modal effects on the human corticospinal system are physiologically demonstrable. They are odorant-specific and, depending on the experimental context, muscle- and action-specific as well. This finding implies potential new diagnostic and rehabilitative applications.

  2. Gas-operated motor systems

    Energy Technology Data Exchange (ETDEWEB)

    Rilett, J.W.

    1980-09-30

    A gas-operated motor system of the stored energy type-as disclosed in U.S. Pat. No. 4,092,830-in which the gas exhausted from the motor is ducted to a chamber during operation of the motor and thereafter compressed back into the gas reservoir vessel. Recompression may be achieved, e.g., by providing the exhaust gas chamber with a movable piston, or by running the motor in the reverse mode as a compressor.

  3. The Effect of Velocity of Joint Mobilization on Corticospinal Excitability in Individuals With a History of Ankle Sprain.

    Science.gov (United States)

    Fisher, Beth E; Piraino, Andrew; Lee, Ya-Yun; Smith, Jo Armour; Johnson, Sean; Davenport, Todd E; Kulig, Kornelia

    2016-07-01

    Study Design Controlled laboratory study. Background Joint mobilization and manipulation decrease pain and improve patient function. Yet, the processes underlying these changes are not well understood. Measures of corticospinal excitability provide insight into potential mechanisms mediated by the central nervous system. Objectives To investigate the differential effects of joint mobilization and manipulation at the talocrural joint on corticospinal excitability in individuals with resolved symptoms following ankle sprain. Methods Twenty-seven participants with a history of ankle sprain were randomly assigned to the control, joint mobilization, or thrust manipulation group. The motor-evoked potential (MEP) and cortical silent period (CSP) of the tibialis anterior and gastrocnemius were obtained with transcranial magnetic stimulation at rest and during active contraction of the tibialis anterior. The slopes of MEP/CSP input/output curves and the maximal MEP/CSP values were calculated to indicate corticospinal excitability. Behavioral measures, including ankle dorsiflexion and dynamic balance, were evaluated. Results A repeated-measures analysis of variance of the MEP slope showed a significant group-by-time interaction for the tibialis anterior at rest (P = .002) and during active contraction (P = .042). After intervention, the thrust manipulation group had an increase in corticospinal excitability, while the corticospinal excitability decreased in the mobilization group. The thrust manipulation group, but not other groups, also demonstrated a significant increase in the maximal MEP amplitude of the tibialis anterior after intervention. Conclusion The findings suggest that joint manipulation and mobilization have different effects on corticospinal excitability. The increased corticospinal excitability following thrust manipulation may provide a window for physical therapists to optimize muscle recruitment and subsequently movement. The trial was registered at

  4. Changes in corticospinal drive to spinal motoneurones following tablet-based practice of manual dexterity

    DEFF Research Database (Denmark)

    Larsen, Lisbeth Højkjær; Jensen, Thor; Christensen, Mark Schram

    2016-01-01

    The use of touch screens, which require a high level of manual dexterity, has exploded since the development of smartphone and tablet technology. Manual dexterity relies on effective corticospinal control of finger muscles, and we therefore hypothesized that corticospinal drive to finger muscles ...... practice is associated with changes in the common corticospinal drive to spinal motoneurons involved in manual dexterity. Tablet-based motor practice may be a motivating training tool for stroke patients who struggle with loss of dexterity....

  5. Corticospinal modulations during bimanual movement with different relative phases

    Directory of Open Access Journals (Sweden)

    Yoshifumi eNomura

    2016-03-01

    Full Text Available The purpose of this study was to investigate corticospinal modulation of bimanual movement with different relative phases (RPs. The participants rhythmically abducted and adducted the right index finger (unimanual movement or both index fingers (bimanual movement with a cyclic duration of 1 s. The RP of bimanual movement, defined as the time difference between one hand movement and the other hand movement, was 0°, 90°, or 180°. Motor evoked potentials in the right flexor dorsal interosseous muscle elicited by transcranial magnetic stimulation were obtained during unimanual or bimanual movement. Corticospinal excitability in the first dorsal interosseous muscle during bimanual movement with 90° RP was higher than that during unimanual movement or bimanual movement with 0° or 180° RP. The correlation between muscle activity level and corticospinal excitability during bimanual movement with 90° RP was smaller than that during unimanual movement or bimanual movement with 0° or 180° RP. The higher corticospinal excitability during bimanual movement with 90° RP may be caused by the greater effort expended to execute a difficult task, the involvement of interhemispheric interaction, a motor binding process, or task acquisition. The lower dependency of corticospinal excitability on the muscle activity level during bimanual movement with 90° RP may reflect the minor corticospinal contribution to bimanual movement with an RP that is not in the attractor state.

  6. Biotinylated dextran amine is an ideal anterograde tracer for the corticospinal tract in a goat model of ischemic corticospinal tract injury

    Institute of Scientific and Technical Information of China (English)

    Xiaoyu Yang; Yufei Gao; Zhigang Qin; Xia Cao; Xinquan Gu

    2011-01-01

    Existing visualized tracer studies of the corticospinal tract have been focused on rodents, which have markedly different spinal cord structures compared with humans. In this study, the segmental artery feeding the spinal cord was embolized with digital subtraction angiography to establish a goat model of ischemic spinal cord injury. Biotinylated dextran amine was injected into the motor function areas of the cortex in goats with ischemic spinal cord injury. The corticospinal tract originates from the cerebral cortex motor function area, and travels towards the lateral funiculus at the contralateral spinal dorsal horn after decussation at the pyramid. The number of corticospinal tract positive fibers was found to be gradually reduced. These findings indicate that digital subtraction angiography can be applied to a goat model of ischemic spinal cord injury. Biotinylated dextran amine visualizes the course of the goat corticospinal tract in the spinal cord, which is similar to the human spinal cord. Biotinylated dextran amine is an ideal tracer for the corticospinal tract.

  7. Corticospinal tract recovery in a patient with traumatic transtentorial herniation

    Institute of Scientific and Technical Information of China (English)

    Sang Seok Yeo; Sung Ho Jang

    2013-01-01

    Transtentorial herniation is one of the causes of motor weakness in traumatic brain injury. In this study, we report on a patient who underwent decompressive craniectomy due to traumatic intracerebral hemorrhage. Brain CT images taken after surgery showed intracerebral hemorrhage in the left fronto-temporal lobe and left transtentorial herniation. The patient presented with severe paralysis of the right extremities at the time of intracerebral hemorrhage onset, but the limb motor function recovered partially at 6 months after onset and to nearly normal level at 27 months. Through diffusion tensor tractography, the left corticospinal tract was disrupted below the cerebral peduncle at 1 month after onset and the disrupted left corticospinal tract was reconstructed at 27 months. These findings suggest that recovery of limb motor function in a patient with traumatic transtentorial herniation can come to be true by recovery of corticospinal tract.

  8. Paired Stimulation to Promote Lasting Augmentation of Corticospinal Circuits

    Directory of Open Access Journals (Sweden)

    Noam Y. Harel

    2016-01-01

    Full Text Available After injury, electrical stimulation of the nervous system can augment plasticity of spared or latent circuits through focal modulation. Pairing stimulation of two parts of a spared circuit can target modulation more specifically to the intended circuit. We discuss 3 kinds of paired stimulation in the context of the corticospinal system, because of its importance in clinical neurorehabilitation. The first uses principles of Hebbian plasticity: by altering the stimulation timing of presynaptic neurons and their postsynaptic targets, synapse function can be modulated up or down. The second form uses synchronized presynaptic inputs onto a common synaptic target. We dub this a “convergent” mechanism, because stimuli have to converge on a common target with coordinated timing. The third form induces focal modulation by tonic excitation of one region (e.g., the spinal cord during phasic stimulation of another (e.g., motor cortex. Additionally, endogenous neural activity may be paired with exogenous electrical stimulation. This review addresses what is known about paired stimulation of the corticospinal system of both humans and animal models, emphasizes how it qualitatively differs from single-site stimulation, and discusses the gaps in knowledge that must be addressed to maximize its use and efficacy in neurorehabilitation.

  9. Impaired transmission in the corticospinal tract and gait disability in spinal cord injured persons

    DEFF Research Database (Denmark)

    Barthélemy, Dorothy; Willerslev-Olsen, Maria; Lundell, Hans Magnus Henrik;

    2010-01-01

    of foot drop. Spinal cord injured participants who exhibited a large foot drop had little or no MEP at rest in the TA muscle and had little or no coherence in the same muscle during walking. Gait speed was correlated to foot drop, and was the lowest in participants with no MEP at rest. The data confirm......Rehabilitation following spinal cord injury is likely to depend on recovery of corticospinal systems. Here we investigate whether transmission in the corticospinal tract may explain foot drop (inability to dorsiflex ankle) in persons with spinal cord lesion. The study was performed in 24 persons...... with incomplete spinal cord lesion (C1 to L1) and 15 healthy controls. Coherence in the 10-20 Hz frequency band between paired tibialis anterior muscle (TA) electromyographic recordings obtained in the swing phase of walking, which is taken as a measure of motor unit synchronization, was significantly correlated...

  10. Improve Motor System Efficiency for a Broad Range of Motors with MotorMaster+ International

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-05-01

    Available at no charge, MotorMaster+ International is designed to support motor systems improvement planning at industrial facilities by identifying the most cost-effective choice when deciding to repair or replace older motor models.

  11. Distributed Stepping Motor Control System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The beam diagnostic devices used at RIBLL are driven by stepper motors, which are controlled by I/O modules based on ISA-bus in an industrial computer. The disadvantages of such mode are that a large number of long cables are used and one computer to control is unsafe. We have developed a distributed stepping motor control system for the remote, local and centralized control of the stepping motors. RS-485 bus is used for the connection between the remote control unit and the local control units. The con...

  12. Can fully automated detection of corticospinal tract damage be used in stroke patients?

    OpenAIRE

    Leff, Alexander P.; Seghier, Mohamed L.; Kou, Nancy; Park, Chang-hyun; Ward, Nick S.

    2013-01-01

    We compared manual infarct definition, which is time-consuming and open to bias, with an automated abnormal tissue detection method in measuring corticospinal tract-infarct overlap volumes in chronic stroke patients to help predict motor outcome.

  13. Saccade suppression exerts global effects on the motor system.

    Science.gov (United States)

    Wessel, Jan R; Reynoso, H Sequoyah; Aron, Adam R

    2013-08-01

    Stopping inappropriate eye movements is a cognitive control function that allows humans to perform well in situations that demand attentional focus. The stop-signal task is an experimental model for this behavior. Participants initiate a saccade toward a target and occasionally have to try to stop the impending saccade if a stop signal occurs. Prior research using a version of this paradigm for limb movements (hand, leg) as well as for speech has shown that rapidly stopping action leads to apparently global suppression of the motor system, as indexed by the corticospinal excitability (CSE) of task-unrelated effectors in studies with transcranial magnetic stimulation (TMS) of M1. Here we measured CSE from the hand with high temporal precision while participants made saccades and while they successfully and unsuccessfully stopped these saccades in response to a stop signal. We showed that 50 ms before the estimated time at which a saccade is successfully stopped there was reduced CSE for the hand, which was task irrelevant. This shows that rapidly stopping eye movements also has global motor effects. We speculate that this arises because rapidly stopping eye movements, like skeleto-motor movements, is possibly achieved via input to the subthalamic nucleus of the basal ganglia, with a putatively broad suppressive effect on thalamocortical drive. Since recent studies suggest that this suppressive effect could also impact nonmotor representations, the present finding points to a possible mechanistic basis for some kinds of distractibility: abrupt-onset stimuli will interrupt ongoing processing by generating global motor and nonmotor effects.

  14. Using a hybrid brain computer interface and virtual reality system to monitor and promote cortical reorganization through motor activity and motor imagery training.

    Science.gov (United States)

    Bermúdez i Badia, S; García Morgade, A; Samaha, H; Verschure, P F M J

    2013-03-01

    Stroke is one of the leading causes of adult disability with high economical and societal costs. In recent years, novel rehabilitation paradigms have been proposed to address the life-long plasticity of the brain to regain motor function. We propose a hybrid brain-computer interface (BCI)-virtual reality (VR) system that combines a personalized motor training in a VR environment, exploiting brain mechanisms for action execution and observation, and a neuro-feedback paradigm using mental imagery as a way to engage secondary or indirect pathways to access undamaged cortico-spinal tracts. Furthermore, we present the development and validation experiments of the proposed system. More specifically, EEG data on nine naïve healthy subjects show that a simultaneous motor activity and motor imagery paradigm is more effective at engaging cortical motor areas and related networks to a larger extent. Additionally, we propose a motor imagery driven BCI-VR version of our system that was evaluated with nine different healthy subjects. Data show that users are capable of controlling a virtual avatar in a motor imagery training task that dynamically adjusts its difficulty to the capabilities of the user. User self-report questionnaires indicate enjoyment and acceptance of the proposed system.

  15. Viewing instructions accompanying action observation modulate corticospinal excitability

    Directory of Open Access Journals (Sweden)

    David James Wright

    2016-02-01

    Full Text Available Action observation interventions may have the potential to contribute to improved motor function in motor (relearning settings by promoting functional activity and plasticity in the motor regions of the brain. Optimal methods for delivering such interventions, however, have yet to be established. This experiment investigated the effect on corticospinal excitability of manipulating the viewing instructions provided to participants (N = 21 prior to action observation. Specifically, motor evoked potential responses measured from the right hand muscles following single-pulse transcranial magnetic stimulation to the left motor cortex were compared when participants were instructed to observe finger-thumb opposition movement sequences: (i passively; (ii with the intent to imitate the observed movement; or (iii whilst simultaneously and actively imagining that they were performing the movement as they observed it. All three action observation viewing instructions facilitated corticospinal excitability to a greater extent than did observation of a static hand. In addition, the extent to which corticospinal excitability was facilitated was greater during combined observation and imagery, compared to passive observation. These findings have important implications for the design of action observation interventions in motor (relearning settings, where instructions that encourage observers to simultaneously imagine themselves performing the observed movement may offer the current optimal method for improving motor function through action observation.

  16. The modulatory effect of electrical stimulation on the excitability of the corticospinal tract varies according to the type of muscle contraction being performed.

    Science.gov (United States)

    Saito, Kei; Sugawara, Kenichi; Miyaguchi, Shota; Matsumoto, Takuya; Kirimoto, Hikari; Tamaki, Hiroyuki; Onishi, Hideaki

    2014-01-01

    Afferent input caused by electrical stimulation of a peripheral nerve increases corticospinal excitability during voluntary contractions, indicating that proprioceptive sensory input arriving at the cortex plays a fundamental role in modulating corticospinal excitability. The purpose of this study was to investigate whether the effect of electrical stimulation on the corticospinal excitability varies according to the type of muscle contraction being performed. Motor-evoked potentials (MEPs) were elicited by transcranial magnetic stimulation (TMS) during a shortening contraction, an isometric contraction, or no contraction of the first dorsal interosseous (FDI) muscle. In some trials, electrical stimulation of the ulnar nerve was performed at 110% of the sensory threshold or 110% of the motor threshold prior to TMS. Electrical stimulation involved either a train of 50 pulses at 10 Hz or a single pulse. Shortening contraction with the train of electrical stimuli significantly increased MEP amplitudes, and the increase was dependent on the type of stimulation. Isometric contraction with the train of electrical stimuli and electrical stimulation without voluntary contraction did not affect MEP amplitudes. A single pulse of electrical stimulation did not affect MEP amplitudes in any condition. Thus, electrical-stimulation-induced modulation of corticospinal excitability varied according to the type of muscle contraction performed and the type of stimulation. These results show that the type of contraction should be considered when using electrical stimulation for rehabilitation in patients with central nervous system lesions.

  17. A case of polymicrogyria in macaque monkey: impact on anatomy and function of the motor system

    Directory of Open Access Journals (Sweden)

    Rouiller Eric M

    2009-12-01

    Full Text Available Abstract Background Polymicrogyria is a malformation of the cerebral cortex often resulting in epilepsy or mental retardation. It remains unclear whether this pathology affects the structure and function of the corticospinal (CS system. The anatomy and histology of the brain of one macaque monkey exhibiting a spontaneous polymicrogyria (PMG monkey were examined and compared to the brain of normal monkeys. The CS tract was labelled by injecting a neuronal tracer (BDA unilaterally in a region where low intensity electrical microstimulation elicited contralateral hand movements (presumably the primary motor cortex in the PMG monkey. Results The examination of the brain showed a large number of microgyri at macro- and microscopic levels, covering mainly the frontoparietal regions. The layered cortical organization was locally disrupted and the number of SMI-32 stained pyramidal neurons in the cortical layer III of the presumed motor cortex was reduced. We compared the distribution of labelled CS axons in the PMG monkey at spinal cervical level C5. The cumulated length of CS axon arbors in the spinal grey matter was not significantly different in the PMG monkey. In the red nucleus, numerous neurons presented large vesicles. We also assessed its motor performances by comparing its capacity to execute a complex reach and grasp behavioral task. The PMG monkey exhibited an increase of reaction time without any modification of other motor parameters, an observation in line with a normal CS tract organisation. Conclusion In spite of substantial cortical malformations in the frontal and parietal lobes, the PMG monkey exhibits surprisingly normal structure and function of the corticospinal system.

  18. Descending corticospinal control of intersegmental dynamics.

    Science.gov (United States)

    Gritsenko, Valeriya; Kalaska, John F; Cisek, Paul

    2011-08-17

    To make an accurate movement, the CNS has to overcome the inherent complexities of the multijoint limb. For example, interaction torques arise when motion of individual arm segments propagates to adjacent segments causing their movement without any muscle contractions. Since these passive joint torques significantly add to the overall torques generated by active muscular contractions, they must be taken into account during planning or execution of goal-directed movements. We investigated the role of the corticospinal tract in compensating for the interaction torques during arm movements in humans. Twelve subjects reached to visual targets with their arm supported by a robotic exoskeleton. Reaching to one target was accompanied by interaction torques that assisted the movement, while reaching to the other target was accompanied by interaction torques that resisted the movement. Corticospinal excitability was assessed at different times during movement using single-pulse transcranial magnetic stimulation (TMS) over the upper-arm region of M1 (primary motor cortex). We found that TMS responses in shoulder monoarticular and elbow-shoulder biarticular muscles changed together with the interaction torques during movements in which the interaction torques were resistive. In contrast, TMS responses did not correlate with assistive interaction torques or with co-contraction. This suggests that the descending motor command includes compensation for passive limb dynamics. Furthermore, our results suggest that compensation for interaction torques involves the biarticular muscles, which span both shoulder and elbow joints and are in a biomechanically advantageous position to provide such compensation.

  19. Characteristics of corticospinal projections to the intrinsic hand muscles in skilled harpists.

    Science.gov (United States)

    Buick, Alison R; Kennedy, Niamh C; Carson, Richard G

    2016-01-26

    The process of learning to play a musical instrument necessarily alters the functional organisation of the cortical motor areas that are involved in generating the required movements. In the case of the harp, the demands placed on the motor system are quite specific. During performance, all digits with the sole exception of the little finger are used to pluck the strings. With a view to elucidating the impact of having acquired this highly specialised musical skill on the characteristics of corticospinal projections to the intrinsic hand muscles, focal transcranial magnetic stimulation (TMS) was used to elicit motor evoked potentials (MEPs) in three muscles (of the left hand): abductor pollicis brevis (APB); first dorsal interosseous (FDI); and abductor digiti minimi (ADM) in seven harpists. Seven non-musicians served as controls. With respect to the FDI muscle-which moves the index finger, the harpists exhibited reliably larger MEP amplitudes than those in the control group. In contrast, MEPs evoked in the ADM muscle-which activates the little finger, were smaller in the harpists than in the non-musicians. The locations on the scalp over which magnetic stimulation elicited discriminable responses in ADM also differed between the harpists and the non-musicians. This specific pattern of variation in the excitability of corticospinal projections to these intrinsic hand muscles exhibited by harpists is in accordance with the idiosyncratic functional demands that are imposed in playing this instrument. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

  20. 卒中后皮质脊髓束Waller变性的DTI表现及其与运动功能受损的关系%Wallerian degeneration of the corticospinal tracts on diffusion tensor imaging after stroke and its relationship with impaired motor function

    Institute of Scientific and Technical Information of China (English)

    方珉; 谢瑞满; 周林江

    2009-01-01

    皮质脊髓束Waller变性是由于其上运动神经元或轴突损伤引起的远端轴突和髓鞘顺行性变性.卒中是引起皮质脊髓束Waller变性的最常见原因.皮质脊髓束Waller变性的常规MRI显示为与原发病灶相连的符合皮质脊髓束走行的条状异常信号,但常规MRI无法显示卒中发生后4周内的Waller变性.MRI弥散张量成像(diffusion tensor imaging,DTI)可早期检测皮质脊髓束Waller变性,且可动态观察从亚急性早期到慢性期的病理变化过程.文章综述了DTI在显示卒中后皮质脊髓束Waller变性,尤其是早期Waller变性中的作用,以及在卒中患者预后判断和后期康复中的价值.%Wallerian degeneration of the corticospinal tracts is the anterograde degener-ation of distal axons and myelin caused by the upper motor neuron injury or axonal injury.Stroke is the most common cause of Wallerian degeneration of the corticospinal tracts. Conventional magnetic resonance imaging (MRI) of Wallerian degeneration of the corticospinal tracts is a linear abnormal signal that connects the original lesion along the corticospinal tracts, but the conventional MRI signal does not reveal Wallerian degeneration until 4 weeks after stroke. Diffusion tensor imaging (DTI) detects early Wallerian degeneration of the corticospinal tracts, and dynamically observes the process of pathological changes from early subacute stage to chronic stage. 1his article reviews Wallerian degeneration of the corticospinal tracts on DTI after stroke, especially the effect in early Wallerian degeneration, as well as the values in predicting prognosis and late rehabilitation in patients with stroke.

  1. Dissociation of Structural and Functional Integrities of the Motor System in Amyotrophic Lateral Sclerosis and Behavioral-Variant Frontotemporal Dementia

    Science.gov (United States)

    Bae, Jong Seok; Ferguson, Michele; Tan, Rachel; Mioshi, Eneida; Simon, Neil; Burrell, James; Vucic, Steve; Hodges, John R.; Kiernan, Matthew C

    2016-01-01

    Background and Purpose This study investigated the structural and functional changes in the motor system in amyotrophic lateral sclerosis (ALS; n=25) and behavioral-variant fronto-temporal dementia (bvFTD; n=17) relative to healthy controls (n=37). Methods Structural changes were examined using a region-of-interest approach, applying voxel-based morphometry for gray-matter changes and diffusion tensor imaging for white-matter changes. Functional changes in the motor system were elucidated using threshold-tracking transcranial magnetic stimulation (TMS) measurements of upper motor-neuron excitability. Results The structural analyses showed that in ALS there were more white-matter changes in the corticospinal and motor-cortex regions and more gray-matter changes in the cerebellum in comparison to controls. bvFTD showed substantial gray- and white-matter changes across virtually all motor-system regions compared to controls, although the brainstem was affected less than the other regions. Direct comparisons across patient groups showed that the gray- and white-matter motor-system changes inclusive of the motor cortex were greater in bvFTD than in ALS. By contrast, the functional integrity of the motor system was more adversely affected in ALS than in bvFTD, with both patient groups showing increased excitability of upper motor neurons compared to controls. Conclusions Cross-correlation of structural and functional data further revealed a neural dissociation of different motor-system regions and tracts covarying with the TMS excitability across both patient groups. The structural and functional motor-system integrities appear to be dissociated between ALS and bvFTD, which represents useful information for the diagnosis of motor-system changes in these two disorders. PMID:26932257

  2. Quantitative Gait Analysis Using a Motorized Treadmill System Sensitively Detects Motor Abnormalities in Mice Expressing ATPase Defective Spastin.

    Science.gov (United States)

    Connell, James W; Allison, Rachel; Reid, Evan

    2016-01-01

    The hereditary spastic paraplegias (HSPs) are genetic conditions in which there is progressive axonal degeneration in the corticospinal tract. Autosomal dominant mutations, including nonsense, frameshift and missense changes, in the gene encoding the microtubule severing ATPase spastin are the most common cause of HSP in North America and northern Europe. In this study we report quantitative gait analysis using a motorized treadmill system, carried out on mice knocked-in for a disease-associated mutation affecting a critical residue in the Walker A motif of the spastin ATPase domain. At 4 months and at one year of age homozygous mutant mice had a number of abnormal gait parameters, including in stride length and stride duration, compared to heterozygous and wild-type littermates. Gait parameters in heterozygous animals did not differ from wild-type littermates. We conclude that quantitative gait analysis using the DigiGait system sensitively detects motor abnormalities in a hereditary spastic paraplegia model, and would be a useful method for analyzing the effects of pharmacological treatments for HSP.

  3. Abnormal modulation of corticospinal excitability in adults with Asperger's syndrome.

    Science.gov (United States)

    Oberman, Lindsay; Eldaief, Mark; Fecteau, Shirley; Ifert-Miller, Fritz; Tormos, Jose Maria; Pascual-Leone, Alvaro

    2012-09-01

    Most candidate genes and genetic abnormalities linked to autism spectrum disorders (ASD) are thought to play a role in developmental and experience-dependent plasticity. As a possible index of plasticity, we assessed the modulation of motor corticospinal excitability in individuals with Asperger's syndrome (AS) using transcranial magnetic stimulation (TMS). We measured the modulatory effects of theta-burst stimulation (TBS) on motor evoked potentials (MEPs) induced by single-pulse TMS in individuals with AS as compared with age-, gender- and IQ-matched neurotypical controls. The effect of TBS lasted significantly longer in the AS group. The duration of the TBS-induced modulation alone enabled the reliable classification of a second study cohort of subjects as AS or neurotypical. The alteration in the modulation of corticospinal excitability in AS is thought to reflect aberrant mechanisms of plasticity, and might provide a valuable future diagnostic biomarker for the disease and ultimately offer a target for novel therapeutic interventions.

  4. Corticospinal mirror neurons.

    Science.gov (United States)

    Kraskov, A; Philipp, R; Waldert, S; Vigneswaran, G; Quallo, M M; Lemon, R N

    2014-01-01

    Here, we report the properties of neurons with mirror-like characteristics that were identified as pyramidal tract neurons (PTNs) and recorded in the ventral premotor cortex (area F5) and primary motor cortex (M1) of three macaque monkeys. We analysed the neurons' discharge while the monkeys performed active grasp of either food or an object, and also while they observed an experimenter carrying out a similar range of grasps. A considerable proportion of tested PTNs showed clear mirror-like properties (52% F5 and 58% M1). Some PTNs exhibited 'classical' mirror neuron properties, increasing activity for both execution and observation, while others decreased their discharge during observation ('suppression mirror-neurons'). These experiments not only demonstrate the existence of PTNs as mirror neurons in M1, but also reveal some interesting differences between M1 and F5 mirror PTNs. Although observation-related changes in the discharge of PTNs must reach the spinal cord and will include some direct projections to motoneurons supplying grasping muscles, there was no EMG activity in these muscles during action observation. We suggest that the mirror neuron system is involved in the withholding of unwanted movement during action observation. Mirror neurons are differentially recruited in the behaviour that switches rapidly between making your own movements and observing those of others.

  5. Overt orienting of spatial attention and corticospinal excitability during action observation are unrelated

    Science.gov (United States)

    Betti, Sonia; Castiello, Umberto; Guerra, Silvia

    2017-01-01

    Observing moving body parts can automatically activate topographically corresponding motor representations in the primary motor cortex (M1), the so-called direct matching. Novel neurophysiological findings from social contexts are nonetheless proving that this process is not automatic as previously thought. The motor system can flexibly shift from imitative to incongruent motor preparation, when requested by a social gesture. In the present study we aim to bring an increase in the literature by assessing whether and how diverting overt spatial attention might affect motor preparation in contexts requiring interactive responses from the onlooker. Experiment 1 shows that overt attention—although anchored to an observed biological movement—can be captured by a target object as soon as a social request for it becomes evident. Experiment 2 reveals that the appearance of a short-lasting red dot in the contralateral space can divert attention from the target, but not from the biological movement. Nevertheless, transcranial magnetic stimulation (TMS) over M1 combined with electromyography (EMG) recordings (Experiment 3) indicates that attentional interference reduces corticospinal excitability related to the observed movement, but not motor preparation for a complementary action on the target. This work provides evidence that social motor preparation is impermeable to attentional interference and that a double dissociation is present between overt orienting of spatial attention and neurophysiological markers of action observation. PMID:28319191

  6. Corticospinal Excitability in Children with Congenital Hemiparesis

    Directory of Open Access Journals (Sweden)

    Chao-Ying Chen

    2016-10-01

    Full Text Available Transcranial magnetic stimulation (TMS can be used as an assessment or intervention to evaluate or influence brain activity in children with hemiparetic cerebral palsy (CP commonly caused by perinatal stroke. This communication report analyzed data from two clinical trials using TMS to assess corticospinal excitability in children and young adults with hemiparetic CP. The results of this communication revealed a higher probability of finding a motor evoked potential (MEP on the non-lesioned hemisphere compared to the lesioned hemisphere (p = 0.005. The resting motor threshold (RMT was lower on the non-lesioned hemisphere than the lesioned hemisphere (p = 0.013. There was a significantly negative correlation between age and RMT (rs = −0.65, p = 0.003. This communication provides information regarding MEP responses, motor thresholds (MTs and the association with age during TMS assessment in children with hemiparetic CP. Such findings contribute to the development of future pediatric studies in neuroplasticity and neuromodulation to influence motor function and recovery after perinatal stroke.

  7. Changes in corticospinal transmission following 8 weeks of ankle joint immobilization

    DEFF Research Database (Denmark)

    Leukel, Christian; Taube, Wolfgang; Rittweger, Jörn;

    2015-01-01

    ) of the primary motor cortex (Hcond). This method allows assessment of transmission in fast (monosynaptic) and slow(er) (polysynaptic) corticospinal pathways. METHODS: 9 subjects underwent 8weeks of unilateral ankle joint immobilization during daytime, 7 subjects served as controls. The measures obtained before...... immobilization. Importantly, Hcond revealed significant facilitation of conditioned reflexes, but only for longer conditioning intervals, suggesting that immobilization increased excitability only of slower, indirect corticospinal pathways. No changes were observed in the control group. Immobilization had...... no significant effects on spinal reflex measures. CONCLUSIONS: 8weeks of ankle joint immobilization was accompanied by pathway-specific modulation of corticospinal transmission. SIGNIFICANCE: It is particularly interesting that fast corticospinal projections were unaffected as these are involved in controlling...

  8. Functional implications of corticospinal tract impairment on gait after spinal cord injury

    DEFF Research Database (Denmark)

    Barthélemy, Dorothy; Knudsen, Hanne; Willerslev-Olsen, Maria

    2013-01-01

    Objective:Maximum toe elevation during walking is an objective measure of foot drop and reflects the impairment of the corticospinal tract (CST) in persons with spinal cord injury (SCI). To determine if this measurement is functionally relevant to ambulatory abilities, we correlated maximum toe...... elevation with clinical physiotherapy tests.Setting:Cross-sectional study, laboratory and clinical settings.Methods:A total of 24 individuals with SCI (American Spinal Injury Association (ASIA) Impairment Scale D) were recruited. Maximum toe elevation during the swing phase of treadmill gait was measured...... with a kinematic system. CST function was assessed in a sitting position by measuring the motor-evoked potentials (MEPs) induced in tibialis anterior muscle with transcranial magnetic stimulation over the motor cortex. Clinical tests performed were 10-m and 6-min walk test (6MWT), Timed-Up and Go (TUG), Walking...

  9. Rotary steerable motor system for underground drilling

    Energy Technology Data Exchange (ETDEWEB)

    Turner, William E. (Durham, CT); Perry, Carl A. (Middletown, CT); Wassell, Mark E. (Kingwood, TX); Barbely, Jason R. (Middletown, CT); Burgess, Daniel E. (Middletown, CT); Cobern, Martin E. (Cheshire, CT)

    2010-07-27

    A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

  10. Rotary steerable motor system for underground drilling

    Science.gov (United States)

    Turner, William E.; Perry, Carl A.; Wassell, Mark E.; Barbely, Jason R.; Burgess, Daniel E.; Cobern, Martin E.

    2008-06-24

    A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

  11. Rotary steerable motor system for underground drilling

    Science.gov (United States)

    Turner, William E.; Perry, Carl A.; Wassell, Mark E.; Barbely, Jason R.; Burgess, Daniel E.; Cobern, Martin E.

    2010-07-27

    A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

  12. Musical groove modulates motor cortex excitability: a TMS investigation.

    Science.gov (United States)

    Stupacher, Jan; Hove, Michael J; Novembre, Giacomo; Schütz-Bosbach, Simone; Keller, Peter E

    2013-07-01

    Groove is often described as a musical quality that can induce movement in a listener. This study examines the effects of listening to groove music on corticospinal excitability. Musicians and non-musicians listened to high-groove music, low-groove music, and spectrally matched noise, while receiving single-pulse transcranial magnetic stimulation (TMS) over the primary motor cortex either on-beat or off-beat. We examined changes in the amplitude of the motor-evoked potentials (MEPs), recorded from hand and arm muscles, as an index of activity within the motor system. Musicians and non-musicians rated groove similarly. MEP results showed that high-groove music modulated corticospinal excitability, whereas no difference occurred between low-groove music and noise. More specifically, musicians' MEPs were larger with high-groove than low-groove music, and this effect was especially pronounced for on-beat compared to off-beat pulses. These results indicate that high-groove music increasingly engages the motor system, and the temporal modulation of corticospinal excitability with the beat could stem from tight auditory-motor links in musicians. Conversely, non-musicians' MEPs were smaller for high-groove than low-groove music, and there was no effect of on- versus off-beat pulses, potentially stemming from suppression of overt movement. In sum, high-groove music engages the motor system, and previous training modulates how listening to music with a strong groove activates the motor system.

  13. Direct motor evoked potentials and cortical mapping using the NIM® nerve monitoring system: A technical note.

    Science.gov (United States)

    Bharadwaj, Suparna; Haji, Faizal; Hebb, Matthew; Chui, Jason

    2017-04-01

    Motor evoked potentials (MEPs) are commonly used to prevent neurological injury when operating in close proximity to the motor cortex or corticospinal pathway. We report a novel application of the NIM® nerve monitoring system (Medtronic@ NIM response 3.0) for intraoperative direct cortical (dc)-MEPs monitoring. A 69-year-old female patient presented with a 4month history of progressive left hemiparesis resulting from a large right sided posterior frontal meningioma that abutted and compressed the motor cortex. Motor cortical mapping and MEPs were indicated. The patient was anesthetized and maintained on total intravenous anesthetics. Compound muscle action potentials (CMAP) of the right upper limb were monitored using the NIM system. After a craniotomy was performed, we first used the Ojemann stimulator (monopolar) for dc-stimulation and then switched to use the monopolar nerve stimulator probe of the NIM system. The CMAP response was successfully elicited using the NIM stimulating probe (pulse width=250s, train frequency=7pulses/s, current=20mA). A gross total resection of the tumor was achieved with intermittent cortical mapping of MEPs. There were no intraoperative complications and the patient's motor function was preserved after the surgery. In this case, we reported the successful use of the NIM nerve monitoring system to elicit dc-MEPs under general anesthesia. The advantages of using this system include a simple set up and application, neurosurgeon familiarity, wide availability and lower cost. dc-MEPs can be achieved using the NIM system. We conclude that the NIM nerve monitoring system is a feasible alternative to standard neurophysiological monitoring systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Learning in a Simple Motor System

    Science.gov (United States)

    Broussard, Dianne M.; Kassardjian, Charles D.

    2004-01-01

    Motor learning is a very basic, essential form of learning that appears to share common mechanisms across different motor systems. We evaluate and compare a few conceptual models for learning in a relatively simple neural system, the vestibulo-ocular reflex (VOR) of vertebrates. We also compare the different animal models that have been used to…

  15. Corticospinal excitability during the processing of handwritten and typed words and non-words.

    Science.gov (United States)

    Gordon, Chelsea L; Spivey, Michael J; Balasubramaniam, Ramesh

    2017-06-09

    A number of studies have suggested that perception of actions is accompanied by motor simulation of those actions. To further explore this proposal, we applied Transcranial magnetic stimulation (TMS) to the left primary motor cortex during the observation of handwritten and typed language stimuli, including words and non-word consonant clusters. We recorded motor-evoked potentials (MEPs) from the right first dorsal interosseous (FDI) muscle to measure cortico-spinal excitability during written text perception. We observed a facilitation in MEPs for handwritten stimuli, regardless of whether the stimuli were words or non-words, suggesting potential motor simulation during observation. We did not observe a similar facilitation for the typed stimuli, suggesting that motor simulation was not occurring during observation of typed text. By demonstrating potential simulation of written language text during observation, these findings add to a growing literature suggesting that the motor system plays a strong role in the perception of written language. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. The motor system and its disorders

    DEFF Research Database (Denmark)

    Rowe, James B; Siebner, Hartwig R

    2012-01-01

    The motor system has been intensively studied using the emerging neuroimaging technologies over the last twenty years. These include early applications of positron emission tomography of brain perfusion, metabolic rate and receptor function, as well as functional magnetic resonance imaging......, tractography from diffusion weighted imaging, and transcranial magnetic stimulation. Motor system research has the advantage of the existence of extensive electrophysiological and anatomical information from comparative studies which enables cross-validation of new methods. We review the impact of neuroimaging...... on the understanding of diverse motor functions, including motor learning, decision making, inhibition and the mirror neuron system. In addition, we show how imaging of the motor system has supported a powerful platform for bidirectional translational neuroscience. In one direction, it has provided the opportunity...

  17. Does intrinsic motivation enhance motor cortex excitability?

    Science.gov (United States)

    Radel, Rémi; Pjevac, Dusan; Davranche, Karen; d'Arripe-Longueville, Fabienne; Colson, Serge S; Lapole, Thomas; Gruet, Mathieu

    2016-11-01

    Intrinsic motivation (IM) is often viewed as a spontaneous tendency for action. Recent behavioral and neuroimaging evidence indicate that IM, in comparison to extrinsic motivation (EM), solicits the motor system. Accordingly, we tested whether IM leads to greater excitability of the motor cortex than EM. To test this hypothesis, we used two different tasks to induce the motivational orientation using either words representing each motivational orientation or pictures previously linked to each motivational orientation through associative learning. Single-pulse transcranial magnetic stimulation over the motor cortex was applied when viewing the stimuli. Electromyographic activity was recorded on the contracted first dorsal interosseous muscle. Two indexes of corticospinal excitability (the amplitude of motor-evoked potential and the length of cortical silent period) were obtained through unbiased automatic detection and analyzed using a mixed model that provided both statistical power and a high level of control over all important individual, task, and stimuli characteristics. Across the two tasks and the two indices of corticospinal excitability, the exposure to IM-related stimuli did not lead to a greater corticospinal excitability than EM-related stimuli or than stimuli with no motivational valence (ps > .20). While these results tend to dismiss the advantage of IM at activating the motor cortex, we suggest alternative hypotheses to explain this lack of effect, which deserves further research. © 2016 Society for Psychophysiological Research.

  18. The nature of corticospinal paths driving human motoneurones during voluntary contractions

    DEFF Research Database (Denmark)

    Butler, Jane E; Larsen, Thomas S; Gandevia, Simon C

    2007-01-01

    The properties of the human motor cortex can be studied non-invasively using transcranial magnetic stimulation (TMS). Stimulation at high intensity excites corticospinal cells with fast conducting axons that make direct connections to motoneurones of human upper limb muscles, while low-intensity ......The properties of the human motor cortex can be studied non-invasively using transcranial magnetic stimulation (TMS). Stimulation at high intensity excites corticospinal cells with fast conducting axons that make direct connections to motoneurones of human upper limb muscles, while low...

  19. Corticospinal Excitability in the Hand Muscles is Decreased During Eye Movement with Visual Occlusion.

    Science.gov (United States)

    Chujo, Yuta; Jono, Yasutomo; Tani, Keisuke; Nomura, Yoshifumi; Hiraoka, Koichi

    2016-02-01

    Corticospinal excitability in the hand muscles decreases during smooth pursuit eye movement. The present study tested a hypothesis that the decrease in corticospinal excitability in the hand muscles at rest during eye movement is not caused by visual feedback but caused by motor commands to the eye muscles. Healthy men (M age = 28.4 yr., SD = 5.2) moved their eyes to the right with visual occlusion (dark goggles) while their arms and hands remained at rest. The motor-evoked potential in the hand muscles was suppressed by 19% in the third quarter of the eye-movement period, supporting a view that motor commands to the eye muscles are the cause of the decrease in corticospinal excitability in the hand muscles. The amount of the suppression was not significantly different among the muscles, indicating that modulation of corticospinal excitability in one muscle induced by eye movement is not dependent on whether eye movement direction and the direction of finger movement when the muscle contracts are identical. Thus, the finding failed to support a hypothetical view that motor commands to the eye muscles concomittantly produce motor commands to the hand muscles. Moreover, the amount of the suppression was not significantly different between the forearm positions, indicating that the suppression was not affected by proprioception of the forearm muscles when visual feedback is absent. © The Author(s) 2016.

  20. Extreme Temperature Motor and Drill System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to the need for motors, actuators and drilling systems that can operate in the harsh venusian environment for extended periods of time, on the order of...

  1. Involving the motor system in decision making.

    Science.gov (United States)

    Wyss, Reto; König, Peter; Verschure, Paul F M J

    2004-02-01

    The control of behaviour is usually understood in terms of three distinct components: sensory processing, decision making and movement control. Recently, this view has been questioned on the basis of physiological and behavioural data, blurring the distinction between these three stages. This raises the question to what extent the motor system itself can contribute to the interpretation of behavioural situations. To investigate this question we use a neural model of sensory motor integration applied to a behaving mobile robot performing a navigation task. We show that the population response of the motor system provides a substrate for the categorization of behavioural situations. This categorization allows for the assessment of the complexity of a behavioural situation and regulates whether higher-level decision making is required to resolve behavioural conflicts. Our model lends credence to an emerging reconceptualization of behavioural control where the motor system can be considered as part of a high-level perceptual system.

  2. Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability

    Science.gov (United States)

    Nogueira-Campos, Anaelli A.; Saunier, Ghislain; Della-Maggiore, Valeria; De Oliveira, Laura A. S.; Rodrigues, Erika C.; Vargas, Claudia D.

    2016-01-01

    The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system. PMID:27625602

  3. Observing grasping actions directed to emotion-laden objects: effects upon corticospinal excitability

    Directory of Open Access Journals (Sweden)

    Anaelli A Nogueira-Campos

    2016-08-01

    Full Text Available The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE. Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1 maximum grip aperture, and (2 object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.

  4. Stathmin is enriched in the developing corticospinal tract.

    Science.gov (United States)

    Fuller, Heidi R; Slade, Robert; Jovanov-Milošević, Nataša; Babić, Mirjana; Sedmak, Goran; Šimić, Goran; Fuszard, Matthew A; Shirran, Sally L; Botting, Catherine H; Gates, Monte A

    2015-11-01

    Understanding the intra- and extracellular proteins involved in the development of the corticospinal tract (CST) may offer insights into how the pathway could be regenerated following traumatic spinal cord injury. Currently, however, little is known about the proteome of the developing corticospinal system. The present study, therefore, has used quantitative proteomics and bioinformatics to detail the protein profile of the rat CST during its formation in the spinal cord. This analysis identified increased expression of 65 proteins during the early ingrowth of corticospinal axons into the spinal cord, and 36 proteins at the period of heightened CST growth. A majority of these proteins were involved in cellular assembly and organization, with annotations being most highly associated with cytoskeletal organization, microtubule dynamics, neurite outgrowth, and the formation, polymerization and quantity of microtubules. In addition, 22 proteins were more highly expressed within the developing CST in comparison to other developing white matter tracts of the spinal cord of age-matched animals. Of these differentially expressed proteins, only one, stathmin 1 (a protein known to be involved in microtubule dynamics), was both highly enriched in the developing CST and relatively sparse in other developing descending and ascending spinal tracts. Immunohistochemical analyses of the developing rat spinal cord and fetal human brain stem confirmed the enriched pattern of stathmin expression along the developing CST, and in vitro growth assays of rat corticospinal neurons showed a reduced length of neurite processes in response to pharmacological perturbation of stathmin activity. Combined, these findings suggest that stathmin activity may modulate axonal growth during development of the corticospinal projection, and reinforces the notion that microtubule dynamics could play an important role in the generation and regeneration of the CST.

  5. Symmetric Structure of Induction Motor Systems

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In this paper, symmetric structure of induction motor system in stationary αβ0 coordinates is studied bythe geometric approach. The results show that the system possesses symmetry (G, θ, Ф) and infinitesimal symme-try. Under certain conditions, the system can be transformed into a form possessing state-space symmetry (G, Ф)and infinitesimal state-space symmetry by means of state feedback and input coordinate base transform. The resultscan be extended to the fifth order induction motor system fed by hysteresis-band current-controlled PWM inverter.

  6. Combined action observation and imagery facilitates corticospinal excitability

    Directory of Open Access Journals (Sweden)

    David James Wright

    2014-11-01

    Full Text Available Observation and imagery of movement both activate similar brain regions to those involved in movement execution. As such, both are recommended as techniques for aiding the recovery of motor function following stroke. Traditionally, action observation and movement imagery have been considered as independent intervention techniques. Researchers have however begun to consider the possibility of combining the two techniques into a single intervention strategy. This study investigated the effect of combined action observation and movement imagery on corticospinal excitability in comparison to either observation or imagery alone. Single-pulse transcranial magnetic stimulation was delivered to the hand representation of the left motor cortex during combined action observation and movement imagery, passive observation, or movement imagery of right index finger abduction-adduction movements or control conditions. Motor evoked potential (MEPs were recorded from the first dorsal interosseous (FDI and abductor digiti minimi (ADM muscles of the right hand. The combined action observation and movement imagery condition produced MEPs of larger amplitude than were obtained during passive observation and control conditions. This effect was only present in the FDI muscle, indicating the facilitation of corticospinal excitability during the combined condition was specific to the muscles involved in the observed/imagined task. These findings have implications for stroke rehabilitation, where combined action observation and movement imagery interventions may prove to be more effective than observation or imagery alone.

  7. Control system for bearingless motor-generator

    Science.gov (United States)

    Kascak, Peter E. (Inventor); Jansen, Ralph H. (Inventor); Dever, Timothy P. (Inventor)

    2010-01-01

    A control system for an electromagnetic rotary drive for bearingless motor-generators comprises a winding configuration comprising a plurality of individual pole pairs through which phase current flows, each phase current producing both a lateral force and a torque. A motor-generator comprises a stator, a rotor supported for movement relative to the stator, and a control system. The motor-generator comprises a winding configuration supported by the stator. The winding configuration comprises at least three pole pairs through which phase current flows resulting in three three-phase systems. Each phase system has a first rotor reference frame axis current that produces a levitating force with no average torque and a second rotor reference frame axis current that produces torque.

  8. Rapid changes in corticospinal excitability during force field adaptation of human walking

    DEFF Research Database (Denmark)

    Barthélemy, Dorothy; Alain, S; Grey, Michael James

    2012-01-01

    Force field adaptation of locomotor muscle activity is one way of studying the ability of the motor control networks in the brain and spinal cord to adapt in a flexible way to changes in the environment. Here, we investigate whether the corticospinal tract is involved in this adaptation. We...... be explained by changes in background TA EMG activity. These effects seemed specific to walking, as similar changes in TA MEP were not seen when seated subjects were tested during static dorsiflexion. These observations suggest that the corticospinal tract contributes to the adaptation of walking...

  9. Development of Traction Drive Motors for the Toyota Hybrid System

    Science.gov (United States)

    Kamiya, Munehiro

    Toyota Motor Corporation developed in 2005 a new hybrid system for a large SUV. This system included the new development of a high-speed traction drive motor achieving a significant increase in power weight ratio. This paper provides an overview of the hybrid system, discusses the characteristics required of a traction drive motor, and presents the technologies employed in the developed motor.

  10. Computer-Controlled, Motorized Positioning System

    Science.gov (United States)

    Vargas-Aburto, Carlos; Liff, Dale R.

    1994-01-01

    Computer-controlled, motorized positioning system developed for use in robotic manipulation of samples in custom-built secondary-ion mass spectrometry (SIMS) system. Positions sample repeatably and accurately, even during analysis in three linear orthogonal coordinates and one angular coordinate under manual local control, or microprocessor-based local control or remote control by computer via general-purpose interface bus (GPIB).

  11. [Motor system physiotherapy of the masticatory organ].

    Science.gov (United States)

    Jagucka-Metel, Wioletta; Brzeska, Paulina; Sobolewska, Ewa; Machoy-Mokrzyńska, Anna; Baranowska, Agata

    2013-01-01

    The motor system of the masticatory organ is a complex morphological and functional structure. Its dysfunctions are manifested by various symptoms within the masticatory apparatus and in distant organs. The paper presents a discussion on the physiotherapeutic procedure for the treatment of disorders in the motor system of the masticatory organ. Therapeutic methods are presented, including: massage, trigger point therapy, kinesitherapy, biofeedback, manual therapy, postural re-education, kinesiotaping, physical interventions (TENS, hyaluronidase iontophoresis, ultrasound, laser therapy, and magnetoledotherapy). The paper points out the role of a comprehensive approach to the patient in order to eliminate the cause of disorders, going beyond symptomatic treatment.

  12. Extensive Spinal Decussation and Bilateral Termination of Cervical Corticospinal Projections in Rhesus Monkeys

    OpenAIRE

    2009-01-01

    To examine neuroanatomical mechanisms underlying fine motor control of the primate hand, adult Rhesus monkeys underwent injections of biotinylated dextran amine (BDA) into the right motor cortex. Spinal axonal anatomy was examined using detailed serial-section reconstruction and modified stereological quantification. 87% of corticospinal tract (CST) axons decussated in the medullary pyramids and descended through the contralateral dorsolateral tract of the spinal cord. 11% of CST axons projec...

  13. Control Systems Lab Using a LEGO Mindstorms NXT Motor System

    Science.gov (United States)

    Kim, Y.

    2011-01-01

    This paper introduces a low-cost LEGO Mindstorms NXT motor system for teaching classical and modern control theories in standard third-year undergraduate courses. The LEGO motor system can be used in conjunction with MATLAB, Simulink, and several necessary toolboxes to demonstrate: 1) a modeling technique; 2) proportional-integral-differential…

  14. Control Systems Lab Using a LEGO Mindstorms NXT Motor System

    Science.gov (United States)

    Kim, Y.

    2011-01-01

    This paper introduces a low-cost LEGO Mindstorms NXT motor system for teaching classical and modern control theories in standard third-year undergraduate courses. The LEGO motor system can be used in conjunction with MATLAB, Simulink, and several necessary toolboxes to demonstrate: 1) a modeling technique; 2) proportional-integral-differential…

  15. System and method for motor speed estimation of an electric motor

    Science.gov (United States)

    Lu, Bin [Kenosha, WI; Yan, Ting [Brookfield, WI; Luebke, Charles John [Sussex, WI; Sharma, Santosh Kumar [Viman Nagar, IN

    2012-06-19

    A system and method for a motor management system includes a computer readable storage medium and a processing unit. The processing unit configured to determine a voltage value of a voltage input to an alternating current (AC) motor, determine a frequency value of at least one of a voltage input and a current input to the AC motor, determine a load value from the AC motor, and access a set of motor nameplate data, where the set of motor nameplate data includes a rated power, a rated speed, a rated frequency, and a rated voltage of the AC motor. The processing unit is also configured to estimate a motor speed based on the voltage value, the frequency value, the load value, and the set of nameplate data and also store the motor speed on the computer readable storage medium.

  16. Corticospinal Excitability of Trunk Muscles during Different Postural Tasks.

    Science.gov (United States)

    Chiou, Shin-Yi; Gottardi, Sam E A; Hodges, Paul W; Strutton, Paul H

    2016-01-01

    Evidence suggests that the primary motor cortex (M1) is involved in both voluntary, goal-directed movements and in postural control. Trunk muscles are involved in both tasks, however, the extent to which M1 controls these muscles in trunk flexion/extension (voluntary movement) and in rapid shoulder flexion (postural control) remains unclear. The purpose of this study was to investigate this question by examining excitability of corticospinal inputs to trunk muscles during voluntary and postural tasks. Twenty healthy adults participated. Transcranial magnetic stimulation was delivered to the M1 to examine motor evoked potentials (MEPs) in the trunk muscles (erector spinae (ES) and rectus abdominis (RA)) during dynamic shoulder flexion (DSF), static shoulder flexion (SSF), and static trunk extension (STE). The level of background muscle activity in the ES muscles was matched across tasks. MEP amplitudes in ES were significantly larger in DSF than in SSF or in STE; however, this was not observed for RA. Further, there were no differences in levels of muscle activity in RA between tasks. Our findings reveal that corticospinal excitability of the ES muscles appears greater during dynamic anticipatory posture-related adjustments than during static tasks requiring postural (SSF) and goal-directed voluntary (STE) activity. These results suggest that task-oriented rehabilitation of trunk muscles should be considered for optimal transfer of therapeutic effect to function.

  17. Corticospinal Excitability of Trunk Muscles during Different Postural Tasks.

    Directory of Open Access Journals (Sweden)

    Shin-Yi Chiou

    Full Text Available Evidence suggests that the primary motor cortex (M1 is involved in both voluntary, goal-directed movements and in postural control. Trunk muscles are involved in both tasks, however, the extent to which M1 controls these muscles in trunk flexion/extension (voluntary movement and in rapid shoulder flexion (postural control remains unclear. The purpose of this study was to investigate this question by examining excitability of corticospinal inputs to trunk muscles during voluntary and postural tasks. Twenty healthy adults participated. Transcranial magnetic stimulation was delivered to the M1 to examine motor evoked potentials (MEPs in the trunk muscles (erector spinae (ES and rectus abdominis (RA during dynamic shoulder flexion (DSF, static shoulder flexion (SSF, and static trunk extension (STE. The level of background muscle activity in the ES muscles was matched across tasks. MEP amplitudes in ES were significantly larger in DSF than in SSF or in STE; however, this was not observed for RA. Further, there were no differences in levels of muscle activity in RA between tasks. Our findings reveal that corticospinal excitability of the ES muscles appears greater during dynamic anticipatory posture-related adjustments than during static tasks requiring postural (SSF and goal-directed voluntary (STE activity. These results suggest that task-oriented rehabilitation of trunk muscles should be considered for optimal transfer of therapeutic effect to function.

  18. System and method for determining stator winding resistance in an AC motor using motor drives

    Science.gov (United States)

    Lu, Bin; Habetler, Thomas G; Zhang, Pinjia

    2013-02-26

    A system and method for determining the stator winding resistance of AC motors is provided. The system includes an AC motor drive having an input connectable to an AC source and an output connectable to an input terminal of an AC motor, a pulse width modulation (PWM) converter having switches therein to control current flow and terminal voltages in the AC motor, and a control system connected to the PWM converter. The control system generates a command signal to cause the PWM converter to control an output of the AC motor drive corresponding to an input to the AC motor, selectively generates a modified command signal to cause the PWM converter to inject a DC signal into the output of the AC motor drive, and determines a stator winding resistance of the AC motor based on the DC signal of at least one of the voltage and current.

  19. Score for neonatal acute physiology-II and neonatal pain predict corticospinal tract development in premature newborns.

    Science.gov (United States)

    Zwicker, Jill G; Grunau, Ruth E; Adams, Elysia; Chau, Vann; Brant, Rollin; Poskitt, Kenneth J; Synnes, Anne; Miller, Steven P

    2013-02-01

    Premature infants are at risk for adverse motor outcomes, including cerebral palsy and developmental coordination disorder. The purpose of this study was to examine the relationship of antenatal, perinatal, and postnatal risk factors for abnormal development of the corticospinal tract, the major voluntary motor pathway, during the neonatal period. In a prospective cohort study, 126 premature neonates (24-32 weeks' gestational age) underwent serial brain imaging near birth and at term-equivalent age. With diffusion tensor tractography, mean diffusivity and fractional anisotropy of the corticospinal tract were measured to reflect microstructural development. Generalized estimating equation models examined associations of risk factors on corticospinal tract development. The perinatal risk factor of greater early illness severity (as measured by the Score for Neonatal Acute Physiology-II [SNAP-II]) was associated with a slower rise in fractional anisotropy of the corticospinal tract (P = 0.02), even after correcting for gestational age at birth and postnatal risk factors (P = 0.009). Consistent with previous findings, neonatal pain adjusted for morphine and postnatal infection were also associated with a slower rise in fractional anisotropy of the corticospinal tract (P = 0.03 and 0.02, respectively). Lessening illness severity in the first hours of life might offer potential to improve motor pathway development in premature newborns.

  20. Dynamic Response Analysis of Motorized Spindle System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; LUO Yi-chao; XU Juan; XIAO Ru-feng; LI Xian-hui

    2013-01-01

    As to motorized spindle system, this paper builds a simplified 3D model of spindle and bearing, performs structure modal analysis, reveals its dynamic characteristics under the free model;furthermore, modifies bearing radial stiffness and number of model, and studies the change of modal parameters. On this basis, through the harmonic response analysis of the finite element model, dy-namic response characteristic caused by imbalance of monitored spindle system and law of vibration response to different amount of unbalance is analyzed.

  1. IMPLEMENTATION AND STUDY OF BLDC MOTOR DRIVE SYSTEM

    OpenAIRE

    2016-01-01

    The BLDC motor  is an electronically commutated dc motor becoming very popular in many applications. There are various speed control methods used for BLDC motor. The performance of BLDC motor drives can be improved using sensored control techniques over sensorless technology. This paper presents Brushless Direct Current motor drive system and its sensored speed control technique with PWM.  Advantages and limitations of sensorless techniques are reviewed and then, sensored speed cont...

  2. Human neural stem cells promote corticospinal axons regeneration and synapse reformation in injured spinal cord of rats

    Institute of Scientific and Technical Information of China (English)

    LIANG Peng; JIN Lian-hong; LIANG Tao; LIU En-zhong; ZHAO Shi-guang

    2006-01-01

    Background Axonal regeneration in lesioned mammalian central nervous system is abortive, and this causes permanent disabilities in individuals with spinal cord injuries. This paper studied the action of neural stem cell (NSC) in promoting corticospinal axons regeneration and synapse reformation in rats with injured spinal cord.Methods NSCs were isolated from the cortical tissue of spontaneous aborted human fetuses in accordance with the ethical request. The cells were discarded from the NSC culture to acquire NSC-conditioned medium. Sixty adult Wistar rats were randomly divided into four groups (n=15 in each): NSC graft, NSC medium, graft control and medium control groups. Microsurgical transection of the spinal cord was performed in all the rats at the T11. The NSC graft group received stereotaxic injections of NSCs suspension into both the spinal cord stumps immediately after transection; graft control group received DMEM injection. In NSC medium group,NSC-conditioned medium was administered into the spinal cord every week; NSC culture medium was administered to the medium control group. Hindlimb motor function was assessed using the BBB Locomotor Rating Scale. Regeneration of biotin dextran amine (BDA) labeled corticospinal tract was assessed. Differentiation of NSCs and the expression of synaptophysin at the distal end of the injured spinal cord were observed under a confocal microscope. Group comparisons of behavioral data were analyzed with ANOVA.Results NSCs transplantation resulted in extensive growth of corticospinal axons and locomotor recovery in adult rats after complete spinal cord transection, the mean BBB scores reached 12.5 in NSC graft group and 2.5 in graft control group (P< 0.05). There was also significant difference in BBB score between the NSC medium (11.7) and medium control groups (3.7, P< 0.05). BDA traces regenerated fibers sprouted across the lesion site and entered the caudal part of the spinal cord. Synaptophysin expression

  3. Changes in corticospinal drive to spinal motoneurones following tablet-based practice of manual dexterity.

    Science.gov (United States)

    Larsen, Lisbeth H; Jensen, Thor; Christensen, Mark S; Lundbye-Jensen, Jesper; Langberg, Henning; Nielsen, Jens B

    2016-02-01

    The use of touch screens, which require a high level of manual dexterity, has exploded since the development of smartphone and tablet technology. Manual dexterity relies on effective corticospinal control of finger muscles, and we therefore hypothesized that corticospinal drive to finger muscles can be optimized by tablet-based motor practice. To investigate this, sixteen able-bodied females practiced a tablet-based game (3 × 10 min) with their nondominant hand requiring incrementally fast and precise pinching movements involving the thumb and index fingers. The study was designed as a semirandomized crossover study where the participants attended one practice- and one control session. Before and after each session electrophysiological recordings were obtained during three blocks of 50 precision pinch movements in a standardized setup resembling the practiced task. Data recorded during movements included electroencephalographic (EEG) activity from primary motor cortex and electromyographic (EMG) activity from first dorsal interosseous (FDI) and abductor pollicis brevis (APB) muscles. Changes in the corticospinal drive were evaluated from coupling in the frequency domain (coherence) between EEG-EMG and EMG-EMG activity. Following motor practice performance improved significantly and a significant increase in EEG-EMGAPB and EMGAPB-EMGFDI coherence in the beta band (15-30 Hz) was observed. No changes were observed after the control session. Our results show that tablet-based motor practice is associated with changes in the common corticospinal drive to spinal motoneurons involved in manual dexterity. Tablet-based motor practice may be a motivating training tool for stroke patients who struggle with loss of dexterity.

  4. Seeing fearful body language rapidly freezes the observer's motor cortex.

    Science.gov (United States)

    Borgomaneri, Sara; Vitale, Francesca; Gazzola, Valeria; Avenanti, Alessio

    2015-04-01

    Fearful body language is a salient signal alerting the observer to the presence of a potential threat in the surrounding environment. Although detecting potential threats may trigger an immediate reduction of motor output in animals (i.e., freezing behavior), it is unclear at what point in time similar reductions occur in the human motor cortex and whether they originate from excitatory or inhibitory processes. Using single-pulse and paired-pulse transcranial magnetic stimulation (TMS), here we tested the hypothesis that the observer's motor cortex implements extremely fast suppression of motor readiness when seeing emotional bodies - and fearful body expressions in particular. Participants observed pictures of body postures and categorized them as happy, fearful or neutral while receiving TMS over the right or left motor cortex at 100-125 msec after picture onset. In three different sessions, we assessed corticospinal excitability, short intracortical inhibition (SICI) and intracortical facilitation (ICF). Independently of the stimulated hemisphere and the time of the stimulation, watching fearful bodies suppressed ICF relative to happy and neutral body expressions. Moreover, happy expressions reduced ICF relative to neutral actions. No changes in corticospinal excitability or SICI were found during the task. These findings show extremely rapid bilateral modulation of the motor cortices when seeing emotional bodies, with stronger suppression of motor readiness when seeing fearful bodies. Our results provide neurophysiological support for the evolutionary notions that emotion perception is inherently linked to action systems and that fear-related cues induce an urgent mobilization of motor reactions.

  5. The Corticospinal Tract: A Biomarker to Categorize Upper Limb Functional Potential in Unilateral Cerebral Palsy

    Science.gov (United States)

    Jaspers, Ellen; Byblow, Winston D.; Feys, Hilde; Wenderoth, Nicole

    2016-01-01

    Children with unilateral cerebral palsy (CP) typically present with largely divergent upper limb sensorimotor deficits and individual differences in response to upper limb rehabilitation. This review summarizes how early brain damage can cause dramatic deviations from the normal anatomy of sensory and motor tracts, resulting in unique “wiring patterns” of the sensorimotor system in CP. Based on the existing literature, we suggest that corticospinal tract (CST) anatomy and integrity constrains sensorimotor function of the upper limb and potentially also the response to treatment. However, it is not possible to infer CST (re)organization from clinical presentation alone and conventional biomarkers, such as time of insult, location, and lesion extent seem to have limited clinical utility. Here, we propose a theoretical framework based on a detailed examination of the motor system using behavioral, neurophysiological, and magnetic resonance imaging measures, akin to those used to predict potential for upper limb recovery of adults after stroke. This theoretical framework might prove useful because it provides testable hypotheses for future research with the goal to develop and validate a clinical assessment flowchart to categorize children with unilateral CP. PMID:26779464

  6. Phase-dependent modulation of corticospinal excitability during the observation of the initial phase of gait.

    Science.gov (United States)

    Takahashi, Makoto; Uchida, Natsuko; Yoshida, Mami; Liang, Nan; Nakazawa, Kimitaka; Sekikawa, Kiyokazu; Inamizu, Tsutomu; Hamada, Hironobu

    2014-12-01

    This study was undertaken to identify the temporal characteristics of corticospinal excitability of tibialis anterior muscle during the observation of the initial phase of gait. For this purpose, using transcranial magnetic stimulation, we recorded motor evoked potentials (MEPs) during the observation of the second step of an actor's first three steps of gait initiation with (complex gait) or without (normal gait) an obstacle and unstable surface. The results demonstrate that (1) MEPs during the observation of the initial phase of normal gait were significantly increased only at early swing phase, but not other phases (mid-swing, heel contact, mid-stance, and heel off) and (2) MEPs during the observation of the initial phase of complex gait were significantly increased at early swing and also at mid-swing and heel contact phases. These findings provide the first evidence that corticospinal excitability during the observation of gait, especially the initial phase, is modulated in phase- and motor-demanded-dependent manners.

  7. Corticospinal excitability of the ankle extensor muscles is enhanced in ballet dancers.

    Science.gov (United States)

    Saito, Sakiko; Obata, Hiroki; Endoh, Takashi; Kuno-Mizumura, Mayumi; Nakazawa, Kimitaka

    2014-09-01

    We tested the corticospinal excitability of the soleus muscle in ballet dancers to clarify whether the presumed long-term repetition of the specific plantarflexion results in changes of excitability in this neural pathway. We compared motor evoked potentials of the soleus muscle at rest and during isometric contraction of the plantar flexors in dancers and non-dancers. The amplitudes of motor evoked potentials elicited by transcranial magnetic stimulation during contraction were examined against the background electromyographic activity. A regression line was calculated for each subject. Results showed that the slope of the regression line is significantly greater in the dancer group than in the control group, suggesting that the corticospinal tract of ballet dancers has adapted to long-term repetition of plantarflexion in daily ballet training.

  8. Cortical and corticospinal output modulations during reaching movements with varying directions and magnitudes of interaction torques.

    Science.gov (United States)

    Asmussen, M J; Bailey, A Z; Nelson, A J

    2015-12-17

    The neural command required to coordinate a multi-joint movement is inherently complex. During multi-joint movement of the limb, the force created from movement at one joint may create a torque at a second joint known as an interaction torque. Interaction torques may be assistive or resistive thereby aiding or opposing the motion of the second joint, respectively. For movement to be effectively controlled, the central nervous system should modulate neural output to the muscles to appropriately account for interaction torques. The present study examined the neural output from the primary motor cortex before and during reaching movements that required different combinations of assistive and resistive interaction torques occurring at the shoulder and elbow joints. Using transcranial magnetic stimulation to probe neural output from the primary motor cortex, results indicate that corticospinal output controlling the upper arm is related to resistive interaction torques occurring at the shoulder joint. Further, cortical output to bi-articular muscles is associated with interaction torque and this may be driven by the fact that these muscles are in an advantageous position to control torques produced between inter-connection segments. Humans have a tendency to avoid reaching movements that involve resistive interaction torques and this may be driven by the requirement of increased neural output associated with these movements.

  9. General Motors Phase II Catalyst System

    Energy Technology Data Exchange (ETDEWEB)

    Canale, R.P.; Winegarden, S.R.; Carlson, C.R.; Miles, D.L.

    1978-01-01

    Three-way catalysts provide a means of catalytically achieving lower NOx emission levels while maintaining good control of HC and CO emissions. However, very accurate control of air-fuel ratio is necessary. The precise air-fuel ratio control required is accomplished by employing a closed loop fuel metering system in conjunction with an exhaust gas sensor and an electronic control unit. To gain production experience with this type of system, General Motors is introducing it on two 1978 engine families sold in California. One is a 2.5 liter L-4 engine and the other is a 3.8 liter V-6 engine. Closed loop controlled carburetors are used on both systems. The components used on both systems are described and emission and fuel economy results are reviewed.

  10. Position Control of Motor Drive Systems: A Data Driven Approach

    Directory of Open Access Journals (Sweden)

    Hossein Parastvand

    2015-08-01

    Full Text Available This paper presents a new model free approach to the design of robust PID controller for the position control of electrical machines, such as induction motor, synchronous motor and DC motor faced to un-modeled dynamics. It is illustrated that knowing the frequency response data is sufficient to calculate the family of robust PID controllers that satisfy -norm on the complementary sensitivity function. The usefulness of the proposed approach is demonstrated through simulation on an induction motor drive system.

  11. Stokes Efficiency of Molecular Motor-Cargo Systems

    Directory of Open Access Journals (Sweden)

    Hongyun Wang

    2008-01-01

    Full Text Available A molecular motor utilizes chemical free energy to generate a unidirectional motion through the viscous fluid. In many experimental settings and biological settings, a molecular motor is elastically linked to a cargo. The stochastic motion of a molecular motor-cargo system is governed by a set of Langevin equations, each corresponding to an individual chemical occupancy state. The change of chemical occupancy state is modeled by a continuous time discrete space Markov process. The probability density of a motor-cargo system is governed by a two-dimensional Fokker-Planck equation. The operation of a molecular motor is dominated by high viscous friction and large thermal fluctuations from surrounding fluid. The instantaneous velocity of a molecular motor is highly stochastic: the past velocity is quickly damped by the viscous friction and the new velocity is quickly excited by bombardments of surrounding fluid molecules. Thus, the theory for macroscopic motors should not be applied directly to molecular motors without close examination. In particular, a molecular motor behaves differently working against a viscous drag than working against a conservative force. The Stokes efficiency was introduced to measure how efficiently a motor uses chemical free energy to drive against viscous drag. For a motor without cargo, it was proved that the Stokes efficiency is bounded by 100% [H. Wang and G. Oster, (2002]. Here, we present a proof for the general motor-cargo system.

  12. Lentiviral vectors express chondroitinase ABC in cortical projections and promote sprouting of injured corticospinal axons.

    Science.gov (United States)

    Zhao, Rong-Rong; Muir, Elizabeth M; Alves, João Nuno; Rickman, Hannah; Allan, Anna Y; Kwok, Jessica C; Roet, Kasper C D; Verhaagen, Joost; Schneider, Bernard L; Bensadoun, Jean-Charles; Ahmed, Sherif G; Yáñez-Muñoz, Rafael J; Keynes, Roger J; Fawcett, James W; Rogers, John H

    2011-09-30

    Several diseases and injuries of the central nervous system could potentially be treated by delivery of an enzyme, which might most effectively be achieved by gene therapy. In particular, the bacterial enzyme chondroitinase ABC is beneficial in animal models of spinal cord injury. We have adapted the chondroitinase gene so that it can direct secretion of active chondroitinase from mammalian cells, and inserted it into lentiviral vectors. When injected into adult rat brain, these vectors lead to extensive secretion of chondroitinase, both locally and from long-distance axon projections, with activity persisting for more than 4 weeks. In animals which received a simultaneous lesion of the corticospinal tract, the vector reduced axonal die-back and promoted sprouting and short-range regeneration of corticospinal axons. The same beneficial effects on damaged corticospinal axons were observed in animals which received the chondroitinase lentiviral vector directly into the vicinity of a spinal cord lesion.

  13. Corticalization of motor control in humans is a consequence of brain scaling in primate evolution.

    Science.gov (United States)

    Herculano-Houzel, Suzana; Kaas, Jon H; de Oliveira-Souza, Ricardo

    2016-02-15

    Control over spinal and brainstem somatomotor neurons is exerted by two sets of descending fibers, corticospinal/pyramidal and extrapyramidal. Although in nonhuman primates the effect of bilateral pyramidal lesions is mostly limited to an impairment of the independent use of digits in skilled manual actions, similar injuries in humans result in the locked-in syndrome, a state of mutism and quadriplegia in which communication can be established only by residual vertical eye movements. This behavioral contrast makes humans appear to be outliers compared with other primates because of our almost total dependence on the corticospinal/pyramidal system for the effectuation of movement. Here we propose, instead, that an increasing preponderance of the corticospinal/pyramidal system over motor control is an expected consequence of increasing brain size in primates because of the faster scaling of the number of neurons in the primary motor cortex over the brainstem and spinal cord motor neuron pools, explaining the apparent uniqueness of the corticalization of motor control in humans. © 2015 Wiley Periodicals, Inc.

  14. System programs design of motors; Sistema de programas de diseno de motores

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Gonzalez Palomas, Oscar; Ciprian Avila, Fernando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    This paper describes the objective of creating the program system for induction motors design SIPRODIMO, its scope, its general characteristics, its structure and the results obtained with its application, as well as the service capacity developed by the Motors Area of the Instituto de Investigaciones Elctricas. [Espanol] En este articulo se describe el objetivo de crear el sistema de programas de diseno de motores de induccion, Siprodimo, su alcance, sus caracteristicas generales, su estructura y los resultados obtenidos con su aplicacion, asi como la capacidad de servicio desarrollada por el area de motores, del Instituto de Investigaciones Electricas.

  15. Real-time changes in corticospinal excitability during voluntary contraction with concurrent electrical stimulation.

    Directory of Open Access Journals (Sweden)

    Tomofumi Yamaguchi

    Full Text Available While previous studies have assessed changes in corticospinal excitability following voluntary contraction coupled with electrical stimulation (ES, we sought to examine, for the first time in the field, real-time changes in corticospinal excitability. We monitored motor evoked potentials (MEPs elicited by transcranial magnetic stimulation and recorded the MEPs using a mechanomyogram, which is less susceptible to electrical artifacts. We assessed the MEPs at each level of muscle contraction of wrist flexion (0%, 5%, or 20% of maximum voluntary contraction during voluntary wrist flexion (flexor carpi radialis (FCR voluntary contraction, either with or without simultaneous low-frequency (10 Hz ES of the median nerve that innervates the FCR. The stimulus intensity corresponded to 1.2 × perception threshold. In the FCR, voluntary contraction with median nerve stimulation significantly increased corticospinal excitability compared with FCR voluntary contraction without median nerve stimulation (p<0.01. In addition, corticospinal excitability was significantly modulated by the level of FCR voluntary contraction. In contrast, in the extensor carpi radialis (ECR, FCR voluntary contraction with median nerve stimulation significantly decreased corticospinal excitability compared with FCR voluntary contraction without median nerve stimulation (p<0.05. Thus, median nerve stimulation during FCR voluntary contraction induces reciprocal changes in cortical excitability in agonist and antagonist muscles. Finally we also showed that even mental imagery of FCR voluntary contraction with median nerve stimulation induced the same reciprocal changes in cortical excitability in agonist and antagonist muscles. Our results support the use of voluntary contraction coupled with ES in neurorehabilitation therapy for patients.

  16. Continuous theta-burst stimulation of the primary motor cortex in essential tremor

    DEFF Research Database (Denmark)

    Hellriegel, Helge; Schulz, Eva M; Siebner, Hartwig R

    2012-01-01

    We investigated whether essential tremor (ET) can be altered by suppressing the corticospinal excitability in the primary motor cortex (M1) with transcranial magnetic stimulation.......We investigated whether essential tremor (ET) can be altered by suppressing the corticospinal excitability in the primary motor cortex (M1) with transcranial magnetic stimulation....

  17. Roles of the orexin system in central motor control.

    Science.gov (United States)

    Hu, Bo; Yang, Nian; Qiao, Qi-Cheng; Hu, Zhi-An; Zhang, Jun

    2015-02-01

    The neuropeptides orexin-A and orexin-B are produced by one group of neurons located in the lateral hypothalamic/perifornical area. However, the orexins are widely released in entire brain including various central motor control structures. Especially, the loss of orexins has been demonstrated to associate with several motor deficits. Here, we first summarize the present knowledge that describes the anatomical and morphological connections between the orexin system and various central motor control structures. In the next section, the direct influence of orexins on related central motor control structures is reviewed at molecular, cellular, circuitry, and motor activity levels. After the summarization, the characteristic and functional relevance of the orexin system's direct influence on central motor control function are demonstrated and discussed. We also propose a hypothesis as to how the orexin system orchestrates central motor control in a homeostatic regulation manner. Besides, the importance of the orexin system's phasic modulation on related central motor control structures is highlighted in this regulation manner. Finally, a scheme combining the homeostatic regulation of orexin system on central motor control and its effects on other brain functions is presented to discuss the role of orexin system beyond the pure motor activity level, but at the complex behavioral level.

  18. The effect of music on corticospinal excitability is related to the perceived emotion: a transcranial magnetic stimulation study.

    Science.gov (United States)

    Giovannelli, Fabio; Banfi, Chiara; Borgheresi, Alessandra; Fiori, Elisa; Innocenti, Iglis; Rossi, Simone; Zaccara, Gaetano; Viggiano, Maria Pia; Cincotta, Massimo

    2013-03-01

    Transcranial magnetic stimulation (TMS) and neuroimaging studies suggest a functional link between the emotion-related brain areas and the motor system. It is not well understood, however, whether the motor cortex activity is modulated by specific emotions experienced during music listening. In 23 healthy volunteers, we recorded the motor evoked potentials (MEP) following TMS to investigate the corticospinal excitability while subjects listened to music pieces evoking different emotions (happiness, sadness, fear, and displeasure), an emotionally neutral piece, and a control stimulus (musical scale). Quality and intensity of emotions were previously rated in an additional group of 30 healthy subjects. Fear-related music significantly increased the MEP size compared to the neutral piece and the control stimulus. This effect was not seen with music inducing other emotional experiences and was not related to changes in autonomic variables (respiration rate, heart rate). Current data indicate that also in a musical context, the excitability of the corticomotoneuronal system is related to the emotion expressed by the listened piece.

  19. Linearizing Control of Induction Motor Based on Networked Control Systems

    Institute of Scientific and Technical Information of China (English)

    Jun Ren; Chun-Wen Li; De-Zong Zhao

    2009-01-01

    A new approach to speed control of induction motors is developed by introducing networked control systems (NCSs) into the induction motor driving system. The control strategy is to stabilize and track the rotor speed of the induction motor when the network time delay occurs in the transport medium of network data. First, a feedback linearization method is used to achieve input-output linearization and decoupling control of the induction motor driving system based on rotor flux model, and then the characteristic of network data is analyzed in terms of the inherent network time delay. A networked control model of an induction motor is established. The sufficient condition of asymptotic stability for the networked induction motor driving system is given, and the state feedback controller is obtained by solving the linear matrix inequalities (LMIs). Simulation results verify the efficiency of the proposed scheme.

  20. Muscular weakness in individuals with HIV associated with a disorganization of the cortico-spinal tract: a multi-modal MRI investigation.

    Directory of Open Access Journals (Sweden)

    Charlotte Bernard

    Full Text Available Motor impairment is highly prevalent in HIV-infected patients. Here, we assess associations between peripheral muscular deficits as evaluated by the 5 sit-to-stand test (5STS and structural integrity of the motor system at a central level. Eighty-six HIV-infected patients receiving combination antiretroviral therapy and with no major cerebral events, underwent an MRI scan and the 5STS. Out of 86 participants, forty presented a score greater than two standard deviations above mean normative scores calculated for the 5STS and were therefore considered as motor-impaired. MRI-structural cerebral parameters were compared to the unimpaired participants. Fractional Anisotropy (FA, Axial Diffusivity (AD and Radial Diffusivity (RD, reflecting microstructural integrity, were extracted from Diffusion-Tensor MRI. Global and regional cerebral volumes or thicknesses were extracted from 3D-T1 morphological MRI. Whereas the two groups did not differ for any HIV variables, voxel-wise analysis revealed that motor-impaired participants present low FA values in various cortico-motor tracts and low AD in left cortico-spinal tract. However, they did not present reduced volumes or thicknesses of the precentral cortices compared to unimpaired participants. The absence of alterations in cortical regions holding motor-neurons might argue against neurodegenerative process as an explanation of White Matter (WM disorganization.

  1. Assessment of the contralesional corticospinal tract in early-onset pediatric hemiplegia: Preliminary findings.

    Science.gov (United States)

    Hawe, Rachel L; Dewald, Jules P A

    2014-01-01

    While pediatric hemiplegia results from a unilateral lesion, the immature state of the brain at the time of injury increases the likelihood of observing changes in the non-lesioned hemisphere as well. The purpose of this preliminary study was to use diffusion tensor imaging to evaluate the contralesional corticospinal tracts in individuals with early-onset pediatric hemiplegia. Twelve individuals with pediatric hemiplegia and ten age-matched controls underwent diffusion tensor imaging (DTI). Corticospinal projections were reconstructed using probabilistic tractography for both the lesioned and contralesional side in pediatric hemiplegia as well as the dominant and non-dominant sides in control subjects. The contralesional tract was found to have decreased white matter integrity relative to control subjects. Compared to controls, the contralesional tract also showed increased tract volume. The increase in volume suggests the presence of ipsilateral corticospinal projections from the contralesional hemisphere that are maintained during development to control the paretic extremities. Decreases in integrity may be explained by diffuse damage or incomplete maturation. The findings of this study support the notion of bilateral motor involvement in pediatric hemiplegia, and the need to address bilateral neural changes as well as motor deficits in this population.

  2. Different corticospinal control between discrete and rhythmic movement of the ankle

    Directory of Open Access Journals (Sweden)

    Yumeno eGoto

    2014-07-01

    Full Text Available We investigated differences in corticospinal and spinal control between discrete and rhythmic ankle movements. Motor evoked potentials (MEPs in the tibialis anterior and soleus muscles and soleus H-reflex were elicited in the middle of the plantar flexion phase during discrete ankle movement or in the initial or later cycles of rhythmic ankle movement. The H-reflex was evoked at an intensity eliciting a small M-wave and MEPs were elicited at an intensity of 1.2 times the motor threshold of the soleus MEPs. Only trials in which background EMG level, ankle angle, and ankle velocity were similar among the movement conditions were included for data analysis. In addition, only trials with a similar M-wave were included for data analysis in the experiment evoking H-reflexes. Results showed that H reflex and MEP amplitudes in the soleus muscle during discrete movement were not significantly different from those during rhythmic movement. MEP amplitude in the tibialis anterior muscle during the later cycles of rhythmic movement was significantly larger than that during the initial cycle of the rhythmic movement or during discrete movement. Higher corticospinal excitability in the tibialis anterior muscle during the later cycles of rhythmic movement may reflect changes in corticospinal control from the initial cycle to the later cycles of rhythmic movement.

  3. System For Characterizing Three-Phase Brushless dc Motors

    Science.gov (United States)

    Howard, David E.; Smith, Dennis A.

    1996-01-01

    System of electronic hardware and software developed to automate measurements and calculations needed to characterize electromechanical performances of three-phase brushless dc motors, associated shaft-angle sensors needed for commutation, and associated brushless tachometers. System quickly takes measurements on all three phases of motor, tachometer, and shaft-angle sensor simultaneously and processes measurements into performance data. Also useful in development and testing of motors with not only three phases but also two, four, or more phases.

  4. Corticospinal excitability changes to anodal tDCS elucidated with NIRS-EEG joint-imaging

    DEFF Research Database (Denmark)

    Jindal, Utkarsh; Sood, Mehak; Chowdhury, Shubhajit Roy;

    2015-01-01

    Transcranial direct current stimulation (tDCS) has been shown to modulate corticospinal excitability. We used near-infrared spectroscopy (NIRS) - electroencephalography (EEG) joint-imaging during and after anodal tDCS to measure changes in mean cerebral haemoglobin oxygen saturation (rSO2) along...... with changes in the log-transformed mean-power of EEG within 0.5 Hz - 11.25 Hz. In two separate studies, we investigated local post-tDCS alterations from baseline at the site of anodal tDCS using NIRS-EEG/tDCS joint-imaging as well as local post-tDCS alterations in motor evoked potentials (MEP...... that the innovative technologies for portable NIRS-EEG neuroimaging may be leveraged to objectively quantify the progress (e.g., corticospinal excitability alterations) and dose tDCS intervention as an adjuvant treatment during neurorehabilitation....

  5. Corticospinal responses of resistance-trained and un-trained males during dynamic muscle contractions

    NARCIS (Netherlands)

    Tallent, J.; Goodall, S.; Hortobagyi, T.; Gibson, A. St Clair; Howatson, G.

    2013-01-01

    Little is known regarding the modulation and the plasticity of the neural pathway interconnecting elements of the central nervous system and skeletal muscle in resistant-trained individuals. The aim of the study was to compare corticospinal and spinal responses measured during dynamic muscle contrac

  6. Passive control of Permanent Magnet Synchronous Motor chaotic systems

    Institute of Scientific and Technical Information of China (English)

    QI Dong-lian; WANG Jia-jun; ZHAO Guang-zhou

    2005-01-01

    Permanent Magnet Synchronous Motor model can exhibit a variety of chaotic phenomena under some choices of system parameters and external input. Based on the property of passive system, the essential conditions were studied, by which Permanent Magnet Synchronous Motor chaotic system could be equivalent to passive system. Using Lyapunov stability theory, the convergence condition deciding the system's characters was discussed. In the convergence condition area, the equivalent passive system could be globally asymptotically stabilized by smooth state feedback.

  7. Upper extremity rehabilitation of stroke: Facilitation of corticospinal excitability using virtual mirror paradigm

    Science.gov (United States)

    2012-01-01

    Background Several experimental studies in stroke patients suggest that mirror therapy and various virtual reality programs facilitate motor rehabilitation. However, the underlying mechanisms for these therapeutic effects have not been previously described. Objectives We attempted to delineate the changes in corticospinal excitability when individuals were asked to exercise their upper extremity using a real mirror and virtual mirror. Moreover, we attempted to delineate the role of visual modulation within the virtual environment that affected corticospinal excitability in healthy subjects and stroke patients. Methods A total of 18 healthy subjects and 18 hemiplegic patients were enrolled into the study. Motor evoked potential (MEP)s from transcranial magnetic stimulation were recorded in the flexor carpi radialis of the non-dominant or affected upper extremity using three different conditions: (A) relaxation; (B) real mirror; and (C) virtual mirror. Moreover, we compared the MEPs from the virtual mirror paradigm using continuous visual feedback or intermittent visual feedback. Results The rates of amplitude increment and latency decrement of MEPs in both groups were higher during the virtual mirror task than during the real mirror. In healthy subjects and stroke patients, the virtual mirror task with intermittent visual feedback significantly facilitated corticospinal excitability of MEPs compared with continuous visual feedback. Conclusion Corticospinal excitability was facilitated to a greater extent in the virtual mirror paradigm than in the real mirror and in intermittent visual feedback than in the continuous visual feedback, in both groups. This provides neurophysiological evidence supporting the application of the virtual mirror paradigm using various visual modulation technologies to upper extremity rehabilitation in stroke patients. PMID:23035951

  8. Upper extremity rehabilitation of stroke: Facilitation of corticospinal excitability using virtual mirror paradigm

    Directory of Open Access Journals (Sweden)

    Kang Youn

    2012-10-01

    Full Text Available Abstract Background Several experimental studies in stroke patients suggest that mirror therapy and various virtual reality programs facilitate motor rehabilitation. However, the underlying mechanisms for these therapeutic effects have not been previously described. Objectives We attempted to delineate the changes in corticospinal excitability when individuals were asked to exercise their upper extremity using a real mirror and virtual mirror. Moreover, we attempted to delineate the role of visual modulation within the virtual environment that affected corticospinal excitability in healthy subjects and stroke patients. Methods A total of 18 healthy subjects and 18 hemiplegic patients were enrolled into the study. Motor evoked potential (MEPs from transcranial magnetic stimulation were recorded in the flexor carpi radialis of the non-dominant or affected upper extremity using three different conditions: (A relaxation; (B real mirror; and (C virtual mirror. Moreover, we compared the MEPs from the virtual mirror paradigm using continuous visual feedback or intermittent visual feedback. Results The rates of amplitude increment and latency decrement of MEPs in both groups were higher during the virtual mirror task than during the real mirror. In healthy subjects and stroke patients, the virtual mirror task with intermittent visual feedback significantly facilitated corticospinal excitability of MEPs compared with continuous visual feedback. Conclusion Corticospinal excitability was facilitated to a greater extent in the virtual mirror paradigm than in the real mirror and in intermittent visual feedback than in the continuous visual feedback, in both groups. This provides neurophysiological evidence supporting the application of the virtual mirror paradigm using various visual modulation technologies to upper extremity rehabilitation in stroke patients.

  9. Upper extremity rehabilitation of stroke: facilitation of corticospinal excitability using virtual mirror paradigm.

    Science.gov (United States)

    Kang, Youn Joo; Park, Hae Kyung; Kim, Hyun Jung; Lim, Taeo; Ku, Jeonghun; Cho, Sangwoo; Kim, Sun I; Park, Eun Sook

    2012-10-04

    Several experimental studies in stroke patients suggest that mirror therapy and various virtual reality programs facilitate motor rehabilitation. However, the underlying mechanisms for these therapeutic effects have not been previously described. We attempted to delineate the changes in corticospinal excitability when individuals were asked to exercise their upper extremity using a real mirror and virtual mirror. Moreover, we attempted to delineate the role of visual modulation within the virtual environment that affected corticospinal excitability in healthy subjects and stroke patients. A total of 18 healthy subjects and 18 hemiplegic patients were enrolled into the study. Motor evoked potential (MEP)s from transcranial magnetic stimulation were recorded in the flexor carpi radialis of the non-dominant or affected upper extremity using three different conditions: (A) relaxation; (B) real mirror; and (C) virtual mirror. Moreover, we compared the MEPs from the virtual mirror paradigm using continuous visual feedback or intermittent visual feedback. The rates of amplitude increment and latency decrement of MEPs in both groups were higher during the virtual mirror task than during the real mirror. In healthy subjects and stroke patients, the virtual mirror task with intermittent visual feedback significantly facilitated corticospinal excitability of MEPs compared with continuous visual feedback. Corticospinal excitability was facilitated to a greater extent in the virtual mirror paradigm than in the real mirror and in intermittent visual feedback than in the continuous visual feedback, in both groups. This provides neurophysiological evidence supporting the application of the virtual mirror paradigm using various visual modulation technologies to upper extremity rehabilitation in stroke patients.

  10. Symmetric corticospinal excitability and representation of vastus lateralis muscle in right-handed healthy subjects.

    Science.gov (United States)

    Al Sawah, Mohomad; Rimawi, Mohammad; Concerto, Carmen; Amer, Bahaa; Cao, Yisheng; D'Antoni, Anthony V; Chusid, Eileen; Battaglia, Fortunato

    2014-10-01

    The purpose of this study was to determine the size and location of the representations of the anterior thigh muscles on the human motor cortex in the dominant and non-dominant hemispheres. Motor-evoked potentials (MEPs) induced by transcranial magnetic stimulation were recorded from the right and left vastus lateralis (rVL, lVL) muscles. A total of ten right-handed healthy volunteers participated in the study. In a single session experiment, we investigated VL muscle corticospinal excitability (motor threshold, MEP size, short interval intracortical inhibition, intracortical facilitation) and cortical representation (map area, volume, and location) in the dominant and non-dominant hemispheres. The motor threshold, MEPs, and intracortical excitability did not differ significantly between the hemispheres (P > 0.05). Furthermore, no difference between sides was found in the location of VL motor representation (mediolateral and anteroposterior axis) or in map area and volume (P > 0.05). Vastus lateralis muscle corticospinal excitability and cortical map were symmetrical in right-handed subjects. Future studies on patients with unilateral lower extremity injuries could examine side-to-side plastic reorganization in corticomotor output and map location in both hemispheres.

  11. Corticospinal Tract Compression by Hematoma in a Patient with Intracerebral Hemorrhage: A Diffusion Tensor Tractography and Functional MRI Study

    Science.gov (United States)

    Jang, Sung-Ho; Lee, Mi Young; Ahn, Sang Ho; Kim, Joong Hwi; Jeong, Dong-Hoon; Choi, Byung Yeun; Lee, Dong Gyu

    2006-01-01

    The purpose of this study was to demonstrate corticospinal tract compression that was due to a hematoma by using diffusion tensor tractography (DTT) and functional MRI (fMRI) in a patient with an intracerebral hemorrhage (ICH). A 23-year-old right-handed woman presented with severe paralysis of her right extremities at the onset of a spontaneous ICH. Over the first three days from onset, the motor function of the affected upper and lower extremities rapidly recovered to the extent that she was able to overcome applied resistance to the affected limbs, and her limbs regained normal function 3 weeks after onset. The tract of the right hemisphere originated from the primary sensori-motor cortex (SM1) and it passed through the known corticospinal tract pathway. However, the tract of the left hemisphere was similar to that of the right hemisphere except that it was displaced to the antero-medial side by the hematoma at the cerebral peduncle. Only the contralateral SM1 area centered on the precentral knob was activated during affected (right) or unaffected (left) hand movements, respectively. In conclusion, fMRI and DTT demonstrated a corticospinal tract compression due to hematoma in this patient. We conclude that the combined use of these two modalities appears to improve the accuracy of investigating the state of the corticospinal tract. PMID:16502496

  12. Corticospinal Tract Tracing in the Marmoset with a Clinical Whole-Body 3T Scanner Using Manganese-Enhanced MRI.

    Science.gov (United States)

    Demain, Boris; Davoust, Carole; Plas, Benjamin; Bolan, Faye; Boulanouar, Kader; Renaud, Luc; Darmana, Robert; Vaysse, Laurence; Vieu, Christophe; Loubinoux, Isabelle

    2015-01-01

    Manganese-enhanced MRI (MEMRI) has been described as a powerful tool to depict the architecture of neuronal circuits. In this study we investigated the potential use of in vivo MRI detection of manganese for tracing neuronal projections from the primary motor cortex (M1) in healthy marmosets (Callithrix Jacchus). We determined the optimal dose of manganese chloride (MnCl2) among 800, 400, 40 and 8 nmol that led to manganese-induced hyperintensity furthest from the injection site, as specific to the corticospinal tract as possible, and that would not induce motor deficit. A commonly available 3T human clinical MRI scanner and human knee coil were used to follow hyperintensity in the corticospinal tract 24h after injection. A statistical parametric map of seven marmosets injected with the chosen dose, 8 nmol, showed the corticospinal tract and M1 connectivity with the basal ganglia, substantia nigra and thalamus. Safety was determined for the lowest dose that did not induce dexterity and grip strength deficit, and no behavioral effects could be seen in marmosets who received multiple injections of manganese one month apart. In conclusion, our study shows for the first time in marmosets, a reliable and reproducible way to perform longitudinal ME-MRI experiments to observe the integrity of the marmoset corticospinal tract on a clinical 3T MRI scanner.

  13. Virtual test system for permanent-magnet DC motor

    Institute of Scientific and Technical Information of China (English)

    崔淑梅; 王悦; 柴凤; 吴红星; 刘宝廷; 程树康

    2003-01-01

    In order to obtain the primary parameters and operating characteristics of a DC motor without directlymeasuring its torque and rational speed, it is proposed to use a PC and a data acquisition card to acquire boththe dynamic and static data of armature current to establish the performance of a DC permanent-magnet motor.The accuracy and validity of this virtual test system proposed were verified by comparing the measurements madewith the system proposed with the measurements made with conventional torque meters. It is concluded from theresults of comparison that from the mathematic model established for the DC permant-magnet motors, both majorparameters and operating characteristics can be directly established for the DC motors without measuring theirtorques and rotational speed, a perfect on-line measurement and test system has been established for the DCpermanent-magnet motors using the theory of virtual test system. The system proposed features shorter test time,higher efficiency and lower cost.

  14. Kinetic energy recovery systems in motor vehicles

    Science.gov (United States)

    Śliwiński, C.

    2016-09-01

    The article draws attention to the increasing environmental pollution caused by the development of vehicle transport and motorization. Different types of design solutions used in vehicles for the reduction of fuel consumption, and thereby emission of toxic gasses into the atmosphere, were specified. Historical design solutions concerning energy recovery devices in mechanical vehicles which used flywheels to accumulate kinetic energy were shown. Developmental tendencies in the area of vehicle manufacturing in the form of hybrid electric and electric devices were discussed. Furthermore, designs of energy recovery devices with electrical energy storage from the vehicle braking and shock absorbing systems were presented. A mechanical energy storing device using a flywheel operating under vacuum was presented, as were advantages and disadvantages of both systems, the limitations they impose on individual constructions and safety issues. The paper also discusses a design concept of an energy recovery device in mechanical vehicles which uses torsion springs as the main components of energy accumulation during braking. The desirability of a cooperation of both the mechanical- and electrical energy recovery devices was indicated.

  15. An Insight into the Time Domain Phenomenon during the Transition Zone from Induction Motor to Synchronous Motor Mode for a Current Source Inverter Fed Synchronous Motor Drive System

    OpenAIRE

    A.B. Chattopadhyay; Sunil Thomas

    2014-01-01

    Modeling of synchronous motor plays a dominant role in designing complicated drive system for different applications, especially large blower fans etc., for steel industries. As synchronous motor has no inherent starting torque generally it is started as an induction motor with the help of a damper winding and it pulls into synchronism under certain conditions. The present study exactly concentrates on this particular zone of transition from induction motor to synchronous motor mode for a cur...

  16. Design of dual DC motor control system based on DSP

    Science.gov (United States)

    Shi, Peicheng; Wang, Suo; Xu, Zengwei; Xiao, Ping

    2017-08-01

    Multi-motor control systems are widely used in actual production and life, such as lifting stages, robots, printing systems. This paper through serial communication between PC and DSP, dual DC motor control system consisting of PC as the host computer, DSP as the lower computer with synchronous PWM speed regulation, commutation and selection functions is designed. It sends digital control instructions with host computer serial debugger to lower computer, to instruct the motor to complete corresponding actions. The hardware and software design of the control system are given, and feasibility and validity of the control system are verified by experiments. The expected design goal is achieved.

  17. Differential expression of secreted phosphoprotein 1 in the motor cortex among primate species and during postnatal development and functional recovery.

    Directory of Open Access Journals (Sweden)

    Tatsuya Yamamoto

    Full Text Available We previously reported that secreted phosphoprotein 1 (SPP1 mRNA is expressed in neurons whose axons form the corticospinal tract (CST of the rhesus macaque, but not in the corresponding neurons of the marmoset and rat. This suggests that SPP1 expression is involved in the functional or structural specialization of highly developed corticospinal systems in certain primate species. To further examine this hypothesis, we evaluated the expression of SPP1 mRNA in the motor cortex from three viewpoints: species differences, postnatal development, and functional/structural changes of the CST after a lesion of the lateral CST (l-CST at the mid-cervical level. The density of SPP1-positive neurons in layer V of the primary motor cortex (M1 was much greater in species with highly developed corticospinal systems (i.e., rhesus macaque, capuchin monkey, and humans than in those with less developed corticospinal systems (i.e., squirrel monkey, marmoset, and rat. SPP1-positive neurons in the macaque monkey M1 increased logarithmically in layer V during postnatal development, following a time course consistent with the increase in conduction velocity of the CST. After an l-CST lesion, SPP1-positive neurons increased in layer V of the ventral premotor cortex, in which compensatory changes in CST function/structure may occur, which positively correlated with the extent of finger dexterity recovery. These results further support the concept that the expression of SPP1 may reflect functional or structural specialization of highly developed corticospinal systems in certain primate species.

  18. ARDOLORES: an Arduino based motors control system for DOLORES

    Science.gov (United States)

    Gonzalez, Manuel; Ventura, H.; San Juan, J.; Di Fabrizio, L.

    2014-07-01

    We present ARDOLORES a custom made motor control system for the DOLORES instrument in use at the TNG telescope. ARDOLORES replaced the original PMAC based motor control system at a fraction of the cost. The whole system is composed by one master Arduino ONE with its Ethernet shield, to handle the communications with the external world through an Ethernet socket, and by one Arduino ONE with its custom motor shield for each axis to be controlled. The communication between the master and slaves Arduinos is made possible through the I2C bus. Also a Java web-service has been written to control the motors from an higher level and provides an external API for the scientific GUI. The system has been working since January 2012 handling the DOLORES motors and has demonstrated to be stable, reliable, and with easy maintenance in both the hardware and the software parts.

  19. A physiological signal that prevents motor skill improvements during consolidation.

    Science.gov (United States)

    Tunovic, Sanjin; Press, Daniel Z; Robertson, Edwin M

    2014-04-01

    Different memories follow different processing pathways. For example, some motor skill memories are enhanced over wakefulness, whereas others are instead enhanced over sleep. The processing pathway that a motor skill memory follows may be determined by functional changes within motor circuits. We tested this idea using transcranial magnetic stimulation to measure corticospinal excitability at 6, 21, 36, 96, and 126 min after participants learnt tasks that either were or were not enhanced over wakefulness. There was no change in corticospinal excitability after learning a motor skill that was subsequently enhanced; whereas, there was a substantial transient decrease in corticospinal excitability after learning a motor skill that was not enhanced. In subsequent experiments, we abolished the decrease in corticospinal excitability by applying theta burst stimulation to either the dorsolateral prefrontal or primary motor cortex, and induced motor skill improvements during consolidation. The motor skill improvements in each experiment were correlated with the corticospinal excitability after learning. Together, these experiments suggest that corticospinal excitability changes act as a physiological signal, which prevents improvements from developing over wakefulness, and so when this signal is abolished improvements are induced. Our observations show that the human brain can actively prevent the processing of memories, and provides insights into the mechanisms that control the fate of memories.

  20. Slit scan radiographic system for intermediate size rocket motors

    Science.gov (United States)

    Bernardi, Richard T.; Waters, David D.

    1992-12-01

    The development of slit-scan radiography capability for the NASA Advanced Computed Tomography Inspection System (ACTIS) computed tomography (CT) scanner at MSFC is discussed. This allows for tangential case interface (bondline) inspection at 2 MeV of intermediate-size rocket motors like the Hawk. Motorized mounting fixture hardware was designed, fabricated, installed, and tested on ACTIS. The ACTIS linear array of x-ray detectors was aligned parallel to the tangent line of a horizontal Hawk motor case. A 5 mm thick x-ray fan beam was used. Slit-scan images were produced with continuous rotation of a horizontal Hawk motor. Image features along Hawk motor case interfaces were indicated. A motorized exit cone fixture for ACTIS slit-scan inspection was also provided. The results of this SBIR have shown that slit scanning is an alternative imaging technique for case interface inspection. More data is required to qualify the technique for bondline inspection.

  1. The corticospinal tract in amyotrophic lateral sclerosis: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, E.; Warmuth-Metz, M. [Department of Neuroradiology, University of Wuerzburg (Germany); Ochs, G.; Pelzl, A. [Department of Neurology, University of Wuerzburg, Wuerzburg (Germany)

    1998-02-01

    Cortical motor neurone loss and corticospinal tract (CST) degeneration are typical of amyotrophic lateral sclerosis (ALS). It is a matter of debate whether qualitative assessment of the CST by MRI is useful in the diagnosis. It is also an open question whether quantitative determination of the T2 relaxation times can improve its value. Signal intensity along the CST on 14 consecutive slices was assessed using arbitrary visual rating on double-echo T2-weighted and proton-density spin-echo images of 21 patients with ALS and 21 age- and sex-matched controls. T2 was determined quantitatively. On the T2-weighted images the patients` ratings did not differ from that of controls. The T2 of patients and controls showed no statistical difference in any slice. There was no correlation between T2 and patient age, duration of the disease, or predominant bulbar, lower or upper motor neurone signs. The only correlation between MRI findings and disease was on the proton-density images: all cases in which the CST was poorly seen were controls; a clearly high-signal CST was seen only in the patients. High conspicuity of the CST was thus specific but not sensitive for the diagnosis of ALS. T2-weighted images and measurement of T2 were not useful for diagnosis. (orig.) With 2 figs., 1 tab., 26 refs.

  2. Albinism: Particular attention to the ocular motor system

    Directory of Open Access Journals (Sweden)

    Richard W Hertle

    2013-01-01

    Full Text Available The purpose of this report is to summarize an understanding of the ocular motor system in patients with albinism. Other than the association of vertical eccentric gaze null positions and asymmetric, (a periodic alternating nystagmus in a large percentage of patients, the ocular motor system in human albinism does not contain unique pathology, rather has "typical" types of infantile ocular oscillations and binocular disorders. Both the ocular motor and afferent visual system are affected to varying degrees in patients with albinism, thus, combined treatment of both systems will maximize visual function.

  3. Albinism: particular attention to the ocular motor system.

    Science.gov (United States)

    Hertle, Richard W

    2013-01-01

    The purpose of this report is to summarize an understanding of the ocular motor system in patients with albinism. Other than the association of vertical eccentric gaze null positions and asymmetric, (a) periodic alternating nystagmus in a large percentage of patients, the ocular motor system in human albinism does not contain unique pathology, rather has "typical" types of infantile ocular oscillations and binocular disorders. Both the ocular motor and afferent visual system are affected to varying degrees in patients with albinism, thus, combined treatment of both systems will maximize visual function.

  4. Counter-Rotating Tandem Motor Drilling System

    Energy Technology Data Exchange (ETDEWEB)

    Kent Perry

    2009-04-30

    Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively compared to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger

  5. Chained Activation of the Motor System during Language Understanding

    Science.gov (United States)

    Marino, Barbara F.; Borghi, Anna M.; Buccino, Giovanni; Riggio, Lucia

    2017-01-01

    Two experiments were carried out to investigate whether and how one important characteristic of the motor system, that is its goal-directed organization in motor chains, is reflected in language processing. This possibility stems from the embodied theory of language, according to which the linguistic system re-uses the structures of the motor system. The participants were presented with nouns of common tools preceded by a pair of verbs expressing grasping or observational motor chains (i.e., grasp-to-move, grasp-to-use, look-at-to-grasp, and look-at-to-stare). They decided whether the tool mentioned in the sentence was the same as that displayed in a picture presented shortly after. A primacy of the grasp-to-use motor chain over the other motor chains in priming the participants' performance was observed in both the experiments. More interestingly, we found that the motor information evoked by the noun was modulated by the specific motor-chain expressed by the preceding verbs. Specifically, with the grasping chain aimed at using the tool, the functional motor information prevailed over the volumetric information, and vice versa with the grasping chain aimed at moving the tool (Experiment 2). Instead, the functional and volumetric information were balanced for those motor chains that comprise at least an observational act (Experiment 1). Overall our results are in keeping with the embodied theory of language and suggest that understanding sentences expressing an action directed toward a tool drives a chained activation of the motor system. PMID:28265247

  6. Design of BLDCM Driving and Control System for Motorized Treadmill

    Institute of Scientific and Technical Information of China (English)

    Qi Zhang; Hui Li; Li-Bin Wang

    2007-01-01

    To satisfy the requirement of developing a new generation of motorized treadmill for a famous domestic manufacturer, a brushless DC motor (BLDCM) driving and control system for motorized treadmill is developed. High integration and reliability of this system are ensured under the condition that intelligent power module (TPM) is used and the protection module is included. Periodic current control method is applied to reduce the average current flowing through the armature winding of the motor when the treadmill is required to start with low speed while large load is added. Piecewise proportion-integration-differentiation (PID) control algorithm is applied to solve the problem of speed fluctuation when impulse load is added. The motorized treadmill of a new generation with the driving and control system has the advantages of high reliability, good speed stability, wide timing scope, low cost, and long life-span. And it is very promising for practical applications.

  7. Motor system evolution and the emergence of high cognitive functions.

    Science.gov (United States)

    Mendoza, Germán; Merchant, Hugo

    2014-11-01

    In human and nonhuman primates, the cortical motor system comprises a collection of brain areas primarily related to motor control. Existing evidence suggests that no other mammalian group has the number, extension, and complexity of motor-related areas observed in the frontal lobe of primates. Such diversity is probably related to the wide behavioral flexibility that primates display. Indeed, recent comparative anatomical, psychophysical, and neurophysiological studies suggest that the evolution of the motor cortical areas closely correlates with the emergence of high cognitive abilities. Advances in understanding the cortical motor system have shown that these areas are also related to functions previously linked to higher-order associative areas. In addition, experimental observations have shown that the classical distinction between perceptual and motor functions is not strictly followed across cortical areas. In this paper, we review evidence suggesting that evolution of the motor system had a role in the shaping of different cognitive functions in primates. We argue that the increase in the complexity of the motor system has contributed to the emergence of new abilities observed in human and nonhuman primates, including the recognition and imitation of the actions of others, speech perception and production, and the execution and appreciation of the rhythmic structure of music. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Local connections of layer 5 GABAergic interneurons to corticospinal neurons

    Directory of Open Access Journals (Sweden)

    Yasuyo H Tanaka

    2011-09-01

    Full Text Available In the local circuit of the cerebral cortex, GABAergic inhibitory interneurons are considered to work in collaboration with excitatory neurons. Although many interneuron subgroups have been described in the cortex, local inhibitory connections of each interneuron subgroup are only partially understood with respect to the functional neuron groups that receive these inhibitory connections. In the present study, we morphologically examined local inhibitory inputs to corticospinal neurons (CSNs in motor areas using transgenic rats in which GABAergic neurons expressed fluorescent protein Venus. By analysis of biocytin-filled axons obtained with whole-cell recording/staining in cortical slices, we classified fast-spiking (FS neurons in layer (L 5 into two types, FS1 and FS2, by their high and low densities of axonal arborization, respectively. We then investigated the connections of FS1, FS2, somatostatin-immunopositive (SOM and other (non-FS/non-SOM interneurons to CSNs that were retrogradely labeled in a Golgi-like manner in motor areas. When close appositions between the axon boutons of the intracellularly labeled interneurons and the somata/dendrites of the retrogradely labeled CSNs were examined electron-microscopically, 74% of these appositions made symmetric synaptic contacts. The axon boutons of single FS1 neurons were 2–4-fold more frequent in appositions to the somata/dendrites of CSNs than those of FS2, SOM and non-FS/non-SOM neurons. Axosomatic appositions were most frequently formed with axon boutons of FS1 and FS2 neurons (approximately 30% and least frequently formed with those of SOM neurons (7%. In contrast, SOM neurons most extensively sent axon boutons to the apical dendrites of CSNs. These results might suggest that motor outputs are controlled differentially by the subgroups of L5 GABAergic interneurons in cortical motor areas. 

  9. Human motor unit recordings: origins and insight into the integrated motor system.

    Science.gov (United States)

    Duchateau, Jacques; Enoka, Roger M

    2011-08-29

    Soon after Edward Liddell [1895-1981] and Charles Sherrington [1857-1952] introduced the concept of a motor unit in 1925 and the necessary technology was developed, the recording of single motor unit activity became feasible in humans. It was quickly discovered by Edgar Adrian [1889-1977] and Detlev Bronk [1897-1975] that the force exerted by muscle during voluntary contractions was the result of the concurrent recruitment of motor units and modulation of the rate at which they discharged action potentials. Subsequent studies found that the relation between discharge frequency and motor unit force was characterized by a sigmoidal function. Based on observations on experimental animals, Elwood Henneman [1915-1996] proposed a "size principle" in 1957 and most studies in humans focussed on validating this concept during various types of muscle contractions. By the end of the 20th C, the experimental evidence indicated that the recruitment order of human motor units was determined primarily by motoneuron size and that the occasional changes in recruitment order were not an intended strategy of the central nervous system. Fundamental knowledge on the function of Sherrington's "common final pathway" was expanded with observations on motor unit rotation, minimal and maximal discharge rates, discharge variability, and self-sustained firing. Despite the great amount of work on characterizing motor unit activity during the first century of inquiry, however, many basic questions remain unanswered and these limit the extent to which findings on humans and experimental animals can be integrated and generalized to all movements.

  10. Insulation system in an integrated motor compressor

    Energy Technology Data Exchange (ETDEWEB)

    Sihvo, V.

    2010-07-01

    A high-speed and high-voltage solid-rotor induction machine provides beneficial features for natural gas compressor technology. The mechanical robustness of the machine enables its use in an integrated motor-compressor. The technology uses a centrifugal compressor, which is mounted on the same shaft with the high-speed electrical machine driving it. No gearbox is needed as the speed is determined by the frequency converter. The cooling is provided by the process gas, which flows through the motor and is capable of transferring the heat away from the motor. The technology has been used in the compressors in the natural gas supply chain in the central Europe. New areas of application include natural gas compressors working at the wellheads of the subsea gas reservoir. A key challenge for the design of such a motor is the resistance of the stator insulation to the raw natural gas from the well. The gas contains water and heavy hydrocarbon compounds and it is far harsher than the sales gas in the natural gas supply network. The objective of this doctoral thesis is to discuss the resistance of the insulation to the raw natural gas and the phenomena degrading the insulation. The presence of partial discharges is analyzed in this doctoral dissertation. The breakdown voltage of the gas is measured as a function of pressure and gap distance. The partial discharge activity is measured on small samples representing the windings of the machine. The electrical field behavior is also modeled by finite element methods. Based on the measurements it has been concluded that the discharges are expected to disappear at gas pressures above 4 - 5 bar. The disappearance of discharges is caused by the breakdown strength of the gas, which increases as the pressure increases. Based on the finite element analysis, the physical length of a discharge seen in the PD measurements at atmospheric pressure was approximated to be 40 - 120 mum. The chemical aging of the insulation when exposed to raw

  11. Modulation of Corticospinal Excitability during Acquisition of Action Sequences by Observation

    Science.gov (United States)

    Sakamoto, Masanori; Moriyama, Noriyoshi; Mizuguchi, Nobuaki; Muraoka, Tetsuro; Kanosue, Kazuyuki

    2012-01-01

    Excitability of the corticospinal pathway increases during observation of an action. However, how corticospinal excitability changes during observation of sequential actions in the course of acquiring novel skills (observational learning) remains unexplored. To investigate this, we used a previously unpracticed sequence of ten hand postures. Participants were asked to repeat observation and replication of the sequence. This block of observation and replication was repeated 5 times. During observation of a given hand posture (OK sign), motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation were recorded from hand muscles. In experiment 1, the OK sign appeared in the 9th position of the sequence. Almost all participants could replicate the OK sign only at the 5th block of the experiment. MEP amplitude was greater than that in the control, and decreased with the stages. This suggested that during observational learning of sequential hand postures MEP changed with the progress of the learning. To evaluate this idea, we performed two additional experiments. In experiment 2, the OK sign appeared in the 2nd position. Almost all participants replicated the OK sign even in the 1st block. The MEP amplitude did not change across stages. In experiment 3, the OK sign appeared in the 9th position, but the order of other signs was randomized in every stage. Many participants were not able to replicate the OK sign even during the 5th block of the experiment. The MEP amplitude did not change across stages. These results suggest that: (1) During observational learning modulation of corticospinal excitability is associated with the learning process. (2) Corticospinal excitability decreases as learning progresses. PMID:22615889

  12. Descending motor pathways and the spinal motor system. Limbic and non-limbic components

    NARCIS (Netherlands)

    G. Holstege (Gert)

    1990-01-01

    textabstractFor a thorough understanding of the descending pathways of the motor system originating in the forebrain, knowledge about the anatomy and function of the structures in the more caudally located parts of the central nervous system is indispensable. In this paper an overview will be

  13. Descending motor pathways and the spinal motor system. Limbic and non-limbic components

    NARCIS (Netherlands)

    G. Holstege (Gert)

    1990-01-01

    textabstractFor a thorough understanding of the descending pathways of the motor system originating in the forebrain, knowledge about the anatomy and function of the structures in the more caudally located parts of the central nervous system is indispensable. In this paper an overview will be presen

  14. Descending motor pathways and the spinal motor system. Limbic and non-limbic components

    NARCIS (Netherlands)

    Holstege, G.

    1991-01-01

    For a thorough understanding of the descending pathways of the motor system originating in the forebrain, knowledge about the anatomy and function of the structures in the more caudally located parts of the central nervous system is indispensable. In this paper an overview will be presented of these

  15. A Novel Single Phase Hybrid Switched Reluctance Motor Drive System

    DEFF Research Database (Denmark)

    Liang, Jianing; Xu, Guoqing; Jian, Linni

    2011-01-01

    In this paper, a novel single phase hybrid switched reluctance motor(SRM) drive system is proposed. It integrated a single phase hybrid SRM and a novel single phase boost converter. This motor can reduce the number of phase switch. And the permanent magnet which is used in the motor can improve t...... SRM reduce the negative torque before zero-crossing point of torque curve, and build desired phase current to generate more power. Some experimental results are done to verify the performance of proposed hybrid SRM drive system....

  16. On Power Stream in Motor or Drive System

    Directory of Open Access Journals (Sweden)

    Paszota Zygmunt

    2016-12-01

    Full Text Available In a motor or a drive system the quantity of power increases in the direction opposite to the direction of power flow. Energy losses and energy efficiency of a motor or drive system must be presented as functions of physical quantities independent of losses. Such quantities are speed and load. But the picture of power stream in a motor or drive system is presented in the literature in the form of traditional Sankey diagram of power decrease in the direction of power flow. The paper refers to Matthew H. Sankey’s diagram in his paper „The Thermal Efficiency of Steam Engines“ of 1898. Presented is also a diagram of power increase in the direction opposite to the direction of power flow. The diagram, replacing the Sankey’s diagram, opens a new prospect for research into power of energy losses and efficiency of motors and drive systems.

  17. DC motor proportional control system for orthotic devices

    Science.gov (United States)

    Blaise, H. T.; Allen, J. R.

    1972-01-01

    Multi-channel proportional control system for operation of dc motors for use with externally-powered orthotic arm braces is described. Components of circuitry and principles of operation are described. Schematic diagram of control circuit is provided.

  18. Photovoltaic-wind hybrid system for permanent magnet DC motor

    Science.gov (United States)

    Nasir, M. N. M.; Lada, M. Y.; Baharom, M. F.; Jaafar, H. I.; Ramani, A. N.; Sulaima, M. F.

    2015-05-01

    Hybrid system of Photovoltaic (PV) - Wind turbine (WT) generation has more advantages and reliable compared to PV or wind turbine system alone. The aim of this paper is to model and design hybrid system of PV-WT supplying 100W permanent-magnet dc motor. To achieve the objective, both of PV and WT are connected to converter in order to get the same source of DC supply. Then both sources were combined and straightly connected to 100W permanent magnet dc motor. All the works in this paper is only applied in circuit simulator by using Matlab Simulink. The output produced from each converter is expected to be suit to the motor specification. The output produced from each renewable energy system is as expected to be high as it can support the motor if one of them is breakdown

  19. Changing ideas about others’ intentions: updating prior expectations tunes activity in the human motor system

    Science.gov (United States)

    Jacquet, Pierre O.; Roy, Alice C.; Chambon, Valérian; Borghi, Anna M.; Salemme, Roméo; Farnè, Alessandro; Reilly, Karen T.

    2016-01-01

    Predicting intentions from observing another agent’s behaviours is often thought to depend on motor resonance – i.e., the motor system’s response to a perceived movement by the activation of its stored motor counterpart, but observers might also rely on prior expectations, especially when actions take place in perceptually uncertain situations. Here we assessed motor resonance during an action prediction task using transcranial magnetic stimulation to probe corticospinal excitability (CSE) and report that experimentally-induced updates in observers’ prior expectations modulate CSE when predictions are made under situations of perceptual uncertainty. We show that prior expectations are updated on the basis of both biomechanical and probabilistic prior information and that the magnitude of the CSE modulation observed across participants is explained by the magnitude of change in their prior expectations. These findings provide the first evidence that when observers predict others’ intentions, motor resonance mechanisms adapt to changes in their prior expectations. We propose that this adaptive adjustment might reflect a regulatory control mechanism that shares some similarities with that observed during action selection. Such a mechanism could help arbitrate the competition between biomechanical and probabilistic prior information when appropriate for prediction. PMID:27243157

  20. Stator insulation systems for medium voltage PWM drives fed motors

    Energy Technology Data Exchange (ETDEWEB)

    Gao, G.; Chen, W. [TECO-Westinghouse Motor Co., Round Rock, TX (United States)

    2005-07-01

    Adjustable speed drives (ASD) are commonly used in power electronics and control systems. It is estimated that more than 15 per cent of medium voltage motors are currently fed by such drives worldwide. A research project was conducted to examine the influence of medium voltage pulse width modulated (PWM) ASD on motor stator insulation systems. The findings, based on accelerated laboratory tests, have helped designers to improve the capabilities of the insulation system used for ASD-fed motors. Repetitive, high magnitude voltage spikes with fast rise time create significant stress on insulation systems. Gradual deterioration and premature failure of the motor insulation can result from surge voltages which generate surface discharges between phase windings/end windings, or partial discharges between stator turns. However, there is no industrial standard to evaluate motor insulation life under ASD-cable-motor conditions. Several material manufacturers have developed their own version of corona resistant material. However, the insulation life of ASD-fed motors does not depend solely on the raw materials. Rather, it depends on the complete insulation system, including the stator manufacturing process. In order to address this problem, TECO-Westinghouse Motor Company has developed special design criteria and manufacturing practices in order to reduce winding insulation temperature and to compensate for the additional heat generated by high frequency contents in the PWM voltage waveform. A patent pending new cooling system should reduce winding temperature by 15 to 20 degrees C. This paper presented design considerations for turn insulation, groundwall insulation, and a voltage stress grading system. A new thermal class H insulation system was also described. 6 refs., 2 tabs., 5 figs.

  1. Three-dimensional white matter tractography by diffusion tensor imaging in ischaemic stroke involving the corticospinal tract

    Energy Technology Data Exchange (ETDEWEB)

    Kunimatsu, A.; Aoki, S.; Masutani, Y.; Abe, O.; Mori, H.; Ohtomo, K. [Department of Radiology, Graduate School of Medicine, Tokyo University, 7-3-1 Hongo, Bunkyo-ku, 113-8655, Tokyo (Japan)

    2003-08-01

    Diffusion tensor MR imaging (DTI) provides information on diffusion anisotropy, which can be expressed with three-dimensional (3D) white matter tractography. We used 3D white matter tractography to show the corticospinal tract in eight patients with acute or early subacute ischaemic stroke involving the posterior limb of the internal capsule or corona radiata and to assess involvement of the tract. Infarcts and the tract were shown simultaneously, providing information on their spatial relationships. In five of the eight patients, 3D fibre tract maps showed the corticospinal tract in close proximity to the infarct but not to pass through it. All these patients recovered well, with maximum improvement from the lowest score on manual muscle testing (MMT) up to the full score through rehabilitation. In the other three patients the corticospinal tract was shown running through the infarct; reduction in MMT did not necessarily improve favourably or last longer, other than in one patient. As 3D white matter tractography can show spatial relationships between the corticospinal tract and an infarct, it might be helpful in prognosis of gross motor function. (orig.)

  2. Multicore Based Open Loop Motor Controller Embedded System for Permanent Magnet Direct Current Motor

    Directory of Open Access Journals (Sweden)

    K. Baskaran

    2012-01-01

    Full Text Available Problem statement: In an advanced electronics world most of the applications are developed by microcontroller based embedded system. Approach: Multicore processor based motor controller was presented to improve the processing speed of the controller and improve the efficiency of the motor by maintaining constant speed. It was based on the combination of Cortex processor (Software core and Field Programmable Gate Arrays (FPGA, Hardware core. These multicore combination were help to design efficient low power motor controller. Results: A functional design of cortex processor and FPGA in this system was completed by using Actel libero IDE and IAR embedded IDE software PWM signal was generated by the proposed processor to control the motor driver circuit. All the function modules were programmed by Very-High-Speed Integrated Circuit Hardware Description Language (VHDL. The advantage of the proposed system was optimized operational performance and low power utility. Multicore processor was used to improve the speed of execution and optimize the performance of the controller. Conclusion: Without having the architectural concept of any motor we can control it by using this method.This is an low cost low power controller and easy to use. The simulation and experiment results verified its validity.

  3. Role of the motor system in language knowledge.

    Science.gov (United States)

    Berent, Iris; Brem, Anna-Katharine; Zhao, Xu; Seligson, Erica; Pan, Hong; Epstein, Jane; Stern, Emily; Galaburda, Albert M; Pascual-Leone, Alvaro

    2015-02-17

    All spoken languages express words by sound patterns, and certain patterns (e.g., blog) are systematically preferred to others (e.g., lbog). What principles account for such preferences: does the language system encode abstract rules banning syllables like lbog, or does their dislike reflect the increased motor demands associated with speech production? More generally, we ask whether linguistic knowledge is fully embodied or whether some linguistic principles could potentially be abstract. To address this question, here we gauge the sensitivity of English speakers to the putative universal syllable hierarchy (e.g., blif ≻ bnif ≻ bdif ≻ lbif) while undergoing transcranial magnetic stimulation (TMS) over the cortical motor representation of the left orbicularis oris muscle. If syllable preferences reflect motor simulation, then worse-formed syllables (e.g., lbif) should (i) elicit more errors; (ii) engage more strongly motor brain areas; and (iii) elicit stronger effects of TMS on these motor regions. In line with the motor account, we found that repetitive TMS pulses impaired participants' global sensitivity to the number of syllables, and functional MRI confirmed that the cortical stimulation site was sensitive to the syllable hierarchy. Contrary to the motor account, however, ill-formed syllables were least likely to engage the lip sensorimotor area and they were least impaired by TMS. Results suggest that speech perception automatically triggers motor action, but this effect is not causally linked to the computation of linguistic structure. We conclude that the language and motor systems are intimately linked, yet distinct. Language is designed to optimize motor action, but its knowledge includes principles that are disembodied and potentially abstract.

  4. Corticospinal excitability is dependent on the parameters of peripheral electric stimulation: a preliminary study.

    Science.gov (United States)

    Chipchase, Lucy S; Schabrun, Siobhan M; Hodges, Paul W

    2011-09-01

    To evaluate the effect of 6 electric stimulation paradigms on corticospinal excitability. Using a same subject pre-post test design, transcranial magnetic stimulation (TMS) was used to measure the responsiveness of corticomotor pathway to biceps and triceps brachii muscles before and after 30 minutes of electric stimulation over the biceps brachii. Six different electric stimulation paradigms were applied in random order, at least 3 days apart. Motor control research laboratory. Healthy subjects (N=10; 5 women, 5 men; mean age ± SD, 26 ± 3.6y). Six different electric stimulation paradigms with varied stimulus amplitude, frequency, and ramp settings. Amplitudes of TMS-induced motor evoked potentials at biceps and triceps brachii normalized to maximal M-wave amplitudes. Electric stimulation delivered at stimulus amplitude sufficient to evoke a sensory response at both 10 Hz and 100 Hz, and stimulus amplitude to create a noxious response at 10 Hz decreased corticomotor responsiveness (all PStimulation sufficient to induce a motor contraction (30 Hz) applied in a ramped pattern to mimic a voluntary activation increased corticomotor responsiveness (P=0.002), whereas constant low- and high-intensity motor stimulation at 10 Hz did not. Corticomotor excitability changes were similar for both the stimulated muscle and its antagonist. Stimulus amplitude (intensity) and the nature (muscle flicker vs contraction) of motor stimulation have a significant impact on changes in corticospinal excitability induced by electric stimulation. Here, we demonstrate that peripheral electric stimulation at stimulus amplitude to create a sensory response reduces corticomotor responsiveness. Conversely, stimulus amplitude to create a motor response increases corticomotor responsiveness, but only the parameters that create a motor response that mimics a voluntary muscle contraction. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Programmable logic controller based synchronous motor excitation system

    Directory of Open Access Journals (Sweden)

    Janda Žarko

    2011-01-01

    Full Text Available This paper presents a 3.5 MW synchronous motor excitation system reconstruction. In the proposed solution programmable logic controller is used to control motor, which drives the turbo compressor. Comparing to some other solutions that are used in similar situations, the proposed solution is superior due to its flexibility and usage of mass-production hardware. Moreover, the implementation of PLC enables easy integration of the excitation system with the other technological processes in the plant as well as in the voltage regulation of 'smart grid' system. Also, implementation of various optimization algorithms can be done comfortably and it does not require additional investment in hardware. Some experimental results that depict excitation current during motor start-up, as well as, measured static characteristics of the motor, were presented.

  6. Wireless and Powerless Sensing Node System Developed for Monitoring Motors

    Directory of Open Access Journals (Sweden)

    Dasheng Lee

    2008-08-01

    Full Text Available Reliability and maintainability of tooling systems can be improved through condition monitoring of motors. However, it is difficult to deploy sensor nodes due to the harsh environment of industrial plants. Sensor cables are easily damaged, which renders the monitoring system deployed to assure the machine’s reliability itself unreliable. A wireless and powerless sensing node integrated with a MEMS (Micro Electro-Mechanical System sensor, a signal processor, a communication module, and a self-powered generator was developed in this study for implementation of an easily mounted network sensor for monitoring motors. A specially designed communication module transmits a sequence of electromagnetic (EM pulses in response to the sensor signals. The EM pulses can penetrate through the machine’s metal case and delivers signals from the sensor inside the motor to the external data acquisition center. By using induction power, which is generated by the motor’s shaft rotation, the sensor node is self-sustaining; therefore, no power line is required. A monitoring system, equipped with novel sensing nodes, was constructed to test its performance. The test results illustrate that, the novel sensing node developed in this study can effectively enhance the reliability of the motor monitoring system and it is expected to be a valuable technology, which will be available to the plant for implementation in a reliable motor management program.

  7. Electric motor systems in developing countries: Opportunities for efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, S.; Monahan, P.; Lewis, P.; Greenberg, S. [Lawrence Berkeley Lab., CA (United States); Nadel, S. [American Council for an Energy-Efficient Economy, Washington, DC (United States)

    1993-08-01

    This report presents an overview of the current status and efficiency improvement potential of industrial motor systems in developing countries. Better management of electric motor systems is of particular relevance in developing countries, where improved efficiency can lead to increased productivity and slower growth in electricity demand. Motor systems currently consume some 65--80% of the industrial electricity in developing countries. Drawing on studies from Thailand, India, Brazil, China, Pakistan, and Costa Rica, we describe potential efficiency gains in various parts of the motor system, from the electricity delivery system through the motor to the point where useful work is performed. We report evidence of a significant electricity conservation potential. Most of the efficiency improvement methods we examine are very cost-effective from a societal viewpoint, but are generally not implemented due to various barriers that deter their adoption. Drawing on experiences in North America, we discuss a range of policies to overcome these barriers, including education, training, minimum efficiency standards, motor efficiency testing protocols, technical assistance programs, and financial incentives.

  8. Plasticity of Corticospinal Neural Control after Locomotor Training in Human Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Maria Knikou

    2012-01-01

    Full Text Available Spinal lesions substantially impair ambulation, occur generally in young and otherwise healthy individuals, and result in devastating effects on quality of life. Restoration of locomotion after damage to the spinal cord is challenging because axons of the damaged neurons do not regenerate spontaneously. Body-weight-supported treadmill training (BWSTT is a therapeutic approach in which a person with a spinal cord injury (SCI steps on a motorized treadmill while some body weight is removed through an upper body harness. BWSTT improves temporal gait parameters, muscle activation patterns, and clinical outcome measures in persons with SCI. These changes are likely the result of reorganization that occurs simultaneously in supraspinal and spinal cord neural circuits. This paper will focus on the cortical control of human locomotion and motor output, spinal reflex circuits, and spinal interneuronal circuits and how corticospinal control is reorganized after locomotor training in people with SCI. Based on neurophysiological studies, it is apparent that corticospinal plasticity is involved in restoration of locomotion after training. However, the neural mechanisms underlying restoration of lost voluntary motor function are not well understood and translational neuroscience research is needed so patient-orientated rehabilitation protocols to be developed.

  9. The corticospinal tract lesion of amyotrophic lateral sclerosis. Magnetic resonance imaging of the spinal cord

    Energy Technology Data Exchange (ETDEWEB)

    Terao, Shin-ichi; Sobue, Gen; Mitsuma, Terunori (Aichi Medical Univ., Nagakute (Japan)); Yasuda, Takeshi; Kachi, Teruhiko

    1994-09-01

    Magnetic resonance imaging by gradient echo method demonstrated lesions of the lateral corticospinal tract at cervical cord levels in three ALS patients. Patient 1 was a 43-year-old woman with common from of ALS. She developed right-side predominant pyramidal signs, and right-side predominant prolongation of central motor conduction time. MRI showed hypersignal intensity areas in the dorsal region of the lateral column at the 4th and 5th cervical segments with right-side predominacy. Patient 2 was a 65-year-old man with pseudopolyneuritic from of ALS, who showed lower motor neuron signs without a pyramidal sign. MRI of the 3rd and 4th cervical cord segments demonstrated bilateral hypersignal intensity areas in the dorsal part of the lateral column. Patient 3 was a 62-year-old man with common form of ALS, who showed marked bilateral pyramidal signs with Babinski's sign. MRI of the 5th cervical spinal cord segment demonstrated bilateral hypersignal intensity areas in the dorsolateral column. MR images of the spinal cord thus obtained corresponded well to the postmortem confirmed degeneration of the spinal corticospinal tract. MRI of the spinal cord performed by gradient echo method would provide additional information on the upper motor neuron involvement in ALS. (author).

  10. System for Monitoring and Analysis of Vibrations at Electric Motors

    Directory of Open Access Journals (Sweden)

    Gabriela Rață

    2014-09-01

    Full Text Available The monitoring of vibration occurring at the electric motors is of paramount importance to ensure their optimal functioning. This paper presents a monitoring system of vibrations occurring at two different types of electric motors, using a piezoelectric accelerometer (ICP 603C11 and a data acquisition board from National Instruments (NI 6009. Vibration signals taken from different parts of electric motors are transferred to computer through the acquisition board. A virtual instrument that allows real-time monitoring and Fourier analysis of signals from the vibration sensor was implemented in LabVIEW.

  11. CSF neurofilament light chain reflects corticospinal tract degeneration in ALS

    Science.gov (United States)

    Menke, Ricarda A L; Gray, Elizabeth; Lu, Ching-Hua; Kuhle, Jens; Talbot, Kevin; Malaspina, Andrea; Turner, Martin R

    2015-01-01

    Objective Diffusion tensor imaging (DTI) is sensitive to white matter tract pathology. A core signature involving the corticospinal tracts (CSTs) has been identified in amyotrophic lateral sclerosis (ALS). Raised neurofilament light chain protein (NfL) in cerebrospinal fluid (CSF) is thought to reflect axonal damage in a range of neurological disorders. The relationship between these two measures was explored. Methods CSF and serum NfL concentrations and DTI acquired at 3 Tesla on the same day were obtained from ALS patients (n = 25 CSF, 40 serum) and healthy, age-similar controls (n = 17 CSF, 25 serum). Within-group correlations between NfL and DTI measures of microstructural integrity in major white matter tracts (CSTs, superior longitudinal fasciculi [SLF], and corpus callosum) were performed using tract-based spatial statistics. Results NfL levels were higher in patients compared to controls. CSF levels correlated with clinical upper motor neuron burden and rate of disease progression. Higher NfL levels were significantly associated with lower DTI fractional anisotropy and increased radial diffusivity in the CSTs of ALS patients, but not in controls. Interpretation Elevated CSF and serum NfL is, in part, a result of CST degeneration in ALS. This highlights the wider potential for combining neurochemical and neuroimaging-based biomarkers in neurological disease. PMID:26273687

  12. Measuring mimicry: general corticospinal facilitation during observation of naturalistic behaviour.

    Science.gov (United States)

    van Schaik, J E; Sacheli, L M; Bekkering, H; Toni, I; Aglioti, S M

    2017-07-01

    Mimicry of others' postures and behaviours forms an implicit yet indispensable component of social interactions. However, whereas numerous behavioural studies have investigated the occurrence of mimicry and its social sensitivity, the underlying neurocognitive mechanisms remain elusive. In this study, single-pulse transcranial magnetic stimulation was used to measure corticospinal facilitation during a naturalistic behaviour observation task adapted from the behavioural mimicry literature. Motor evoked potentials (MEPs) in participants' right hands were measured as they observed stimulus videos of a confederate describing photographs. MEPs were recorded while confederates were and were not carrying out hand and leg behaviours that also differed in spatial extent (i.e. large behaviours: face rubbing and leg crossing; small behaviours: finger tapping and foot bouncing). Importantly, the cover task instructions did not refer to the behaviours but instead required participants to focus on the confederates' photograph descriptions in order to later perform a recognition test. A general arousal effect was found, with higher MEPs during stimulus video observation than during a fixation-cross baseline, regardless of whether or not the confederate was carrying out a behaviour at the time of the pulse. When controlling for this general arousal effect, results showed that MEPs during observation of the larger two behaviours were significantly higher than the smaller two behaviours, irrespective of effector. Thus, using a controlled yet naturalistic paradigm, this study suggests that general sensorimotor arousal during social interactions could play a role in implicit behavioural mimicry. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  13. Three-phase multilevel solar inverter for motor drive system

    Science.gov (United States)

    Bhasagare, Mayuresh P.

    This thesis deals with three phase inverters and the different control strategies that can be associated with an inverter being used together. The first part of this thesis discusses the present research in the fields of PV panels, motor drive systems and three phase inverters along with their control. This control includes various strategies like MPPT, Volts-Hertz and modulation index compensation. Incorporating these techniques together is the goal of this thesis. A new topology for operating an open end motor drive system has also been discusses, where a boost converter and a flyback converter have been used in cascade to run a three phase motor. The main advantage of this is increasing the number of levels and improving the quality of the output voltage, not to mention a few other benefits of having the proposed circuit. A new algorithm has also been designed for starting and stopping the motor, which controls the current drawn from the power source during starting.

  14. A Diagnostic System for Speed-Varying Motor Rotary Faults

    Directory of Open Access Journals (Sweden)

    Chwan-Lu Tseng

    2014-01-01

    Full Text Available This study proposed an intelligent rotary fault diagnostic system for motors. A sensorless rotational speed detection method and an improved dynamic structural neural network are used. Moreover, to increase the convergence speed of training, a terminal attractor method and a hybrid discriminant analysis are also adopted. The proposed method can be employed to detect the rotary frequencies of motors with varying speeds and can enhance the discrimination of motor faults. To conduct the experiments, this study used wireless sensor nodes to transmit vibration data and employed MATLAB to write codes for functional modules, including the signal processing, sensorless rotational speed estimation, neural network, and stochastic process control chart. Additionally, Visual Basic software was used to create an integrated human-machine interface. The experimental results regarding the test of equipment faults indicated that the proposed novel diagnostic system can effectively estimate rotational speeds and provide superior ability of motor fault discrimination with fast training convergence.

  15. The new General Motors diesel engine management system; Die neue Dieselmotor-Steuerung von General Motors

    Energy Technology Data Exchange (ETDEWEB)

    Graglia, Riccardo; Catanese, Alessandro; Parisi, Filippo; Barbero, Simone [General Motors Powertrain Europe S.r.L., Turin (Italy)

    2011-02-15

    For more than ten years, General Motors has been developing ECUs for spark-ignition engines in-house. The company has now also developed an engine management system for diesel engines that offers such features as closed-loop injector control and integrated glow plug electronics. (orig.)

  16. Switch Reluctance Motor Control Based on Fuzzy Logic System

    Directory of Open Access Journals (Sweden)

    S. Aleksandrovsky

    2012-01-01

    Full Text Available Due to its intrinsic simplicity and reliability, the switched reluctance motor (SRM has now become a promising candidate for variable-speed drive applications as an alternative induction motor in various industrial application. However, the SRM has the disadvantage of nonlinear characteristic and control. It is suggested to use controller based on fuzzy logic system. Design of FLS controller and simulation model presented.

  17. Brain-robot interface driven plasticity: Distributed modulation of corticospinal excitability.

    Science.gov (United States)

    Kraus, Dominic; Naros, Georgios; Bauer, Robert; Leão, Maria Teresa; Ziemann, Ulf; Gharabaghi, Alireza

    2016-01-15

    Brain-robot interfaces (BRI) are studied as novel interventions to facilitate functional restoration in patients with severe and persistent motor deficits following stroke. They bridge the impaired connection in the sensorimotor loop by providing brain-state dependent proprioceptive feedback with orthotic devices attached to the hand or arm of the patients. The underlying neurophysiology of this BRI neuromodulation is still largely unknown. We investigated changes of corticospinal excitability with transcranial magnetic stimulation in thirteen right-handed healthy subjects who performed 40min of kinesthetic motor imagery receiving proprioceptive feedback with a robotic orthosis attached to the left hand contingent to event-related desynchronization of the right sensorimotor cortex in the β-band (16-22Hz). Neural correlates of this BRI intervention were probed by acquiring the stimulus-response curve (SRC) of both motor evoked potential (MEP) peak-to-peak amplitudes and areas under the curve. In addition, a motor mapping was obtained. The specificity of the effects was studied by comparing two neighboring hand muscles, one BRI-trained and one control muscle. Robust changes of MEP amplitude but not MEP area occurred following the BRI intervention, but only in the BRI-trained muscle. The steep part of the SRC showed an MEP increase, while the plateau of the SRC showed an MEP decrease. MEP mapping revealed a distributed pattern with a decrease of excitability in the hand area of the primary motor cortex, which controlled the BRI, but an increase of excitability in the surrounding somatosensory and premotor cortex. In conclusion, the BRI intervention induced a complex pattern of modulated corticospinal excitability, which may boost subsequent motor learning during physiotherapy.

  18. Development of the Gross Motor Function Classification System (1997)

    Science.gov (United States)

    Morris, Christopher

    2008-01-01

    To address the need for a standardized system to classify the gross motor function of children with cerebral palsy, the authors developed a five-level classification system analogous to the staging and grading systems used in medicine. Nominal group process and Delphi survey consensus methods were used to examine content validity and revise the…

  19. Neuronal communication through coherence in the human motor system

    NARCIS (Netherlands)

    Schoffelen, J.M.

    2007-01-01

    This thesis explores the concept of neuronal communication through oscillatory synchronization. For most of the described research, we used the human motor system as a model system, in particular the cortico spinal system, in combination with non invasive recording techniques. Oscillatory

  20. Hydraulic Motor Driving Variable-Pitch System for Wind Turbine

    Directory of Open Access Journals (Sweden)

    Ye HUANG

    2013-11-01

    Full Text Available The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch system, the present hydraulic variable-pitch mechanism should be changed as follows: hydraulic motors are used to drive gears; gears drive blades; the electro-hydraulic proportional valves are used to control hydraulic motors. The hydraulic control part and electrical control part of variable-pitch system is redesigned. The new variable-pitch system is called hydraulic motor driving variable-pitch system. The new variable-pitch system meets the control requirements of blade pitch, makes the structure simple and its application effect is perfect.    

  1. A New Torque Control System of Permanent Magnet Synchronous Motor

    Directory of Open Access Journals (Sweden)

    Evstratov Andrey

    2017-01-01

    Full Text Available The article describes a new approach to control of permanent magnet synchronous motor drive based on the analysis of the electromechanical transformation. The proposed control system provides quick response and low ripple of the motor torque and flux. To synthesis this control system, the authors put the electromagnetic torque and the modulus of stator flux vector as controlled values and use the Lyapunov’s second method. In addition, the stator voltage constriction and ability of low-pass filtration are taken into account. The investigation of the proposed control system has carried out with the simulation and the experimental research which have confirmed that the proposed control system correspond to all above-mentioned control tasks and the permanent magnet synchronous motor controlled under this system may be recommended to use in robotics.

  2. Single-to-three phase induction motor sensorless drive system

    Directory of Open Access Journals (Sweden)

    Z.M.S. El-Barbary

    2012-06-01

    Full Text Available This paper presented a single to three-phase induction motor drive system to provide variable output voltage and frequency. The proposed drive system employs only six IGBT switches, which form the front-end rectifier and the output inverter for the one step conversion from single-phase supply to output three-phase supply. The front-end rectifier permits bidirectional power flow and provides excellent regulation against fluctuations in source voltage. Moreover, it incorporates active input current shaping feature. The control strategy of the proposed drive system of three-phase induction motor is based on speed sensorless vector control technique. A low cost of motor drive and much more advantages can be achieved using the proposed drive system. Simulation and experimental results are carried out to analysis and explore the characteristics of the proposed drive system.

  3. Biotinylated dextran amine as a neural tracer in the rat corticospinal tract

    Institute of Scientific and Technical Information of China (English)

    Biao Gong; Changqing Li; Xiaofeng Li; Ying Wang

    2008-01-01

    BACKGROUND: The corticospinal tract is the core structure of cerebral control of extremity movement and plasticity, which are prerequisites for movement rehabilitation after brain injury. The measurement and assessment of plasticity changes within the corticospinal tract has become one of the key goals in this field.OBJECTIVE: To explore the effects of biotinylated dextran amine (BDA) as a neural tracer in the rat corticospinal tract and the possibilities of assessing plasticity within the corticospinal tract.DESIGN: An observational experiment.SETTING: Department of Acupuncture of Chinese Medical College, Chongqing Medical University, Department of Neurology, the Second Affiliated Hospital, Chongqing Medical University.MATERIALS: Eighteen male adult Sprague Dawley (SD) rats of clean grade, weighing 200-250 g, were provided by the experimental animal center of Chongqing Medical University. The animal procedures in this study were in accordance with the animal ethics standards. BDA was provided by Vector Laboratories Company (USA, catalogue Sp-1140; serial number R0721).METHODS: This experiment was performed in the Laboratory of Chongqing Medical University between September and December 2006. Adult SD rats were used in the experiment and 15% BDA was injected slowly with a mini-syringe through two round (3 mm diameter) holes into the left sensory and motor cortex. The center of one hole was located 3 mm anterior from the anterior fontanel and 1.5 mm left of the midline; the second hole was located 1.5 mm posterior from the anterior fontanel and 4 mm left of the midline. Three injections were made at each hole at three different levels: 1.4, 1.2, and 1 mm ventral from the surface of the flat skull. After 14 days, the brains and spinal cords were removed and frozen. Sections were cut on a cryostat and BDA transportation absorbed by axons was observed under a fluorescence microscope.MAIN OUTCOME MEASURES: Axonal absorption and transportation of BDA was observed under

  4. Hemispheric differences in corticospinal excitability and in transcallosal inhibition in relation to degree of handedness.

    Directory of Open Access Journals (Sweden)

    Travis Davidson

    Full Text Available In this study, we examined hemispheric differences in corticospinal excitability and in transcallosal inhibition in a selected group of young adults (n = 34 grouped into three handedness categories (RH: strongly right-handed, n = 17; LH: strongly left-handed, n = 10; MH: mixed-handed, n = 7 based on laterality quotients (LQ derived from the Edinburgh Handedness Inventory. Performance measures were also used to derive a laterality index reflecting right-left asymmetries in manual dexterity (Dextli and in finger tapping speed (Speedli. Corticospinal excitability was assessed in each hemisphere by means of transcranial magnetic stimulation (TMS using the first dorsal interosseus as the target muscle. TMS measures consisted of resting motor threshold (rMT, motor evoked potential (MEP recruitment curve (RC and the contralateral silent period (cSP with the accompanying MEP facilitation. Hemispheric interactions were assessed by means of the ipsilateral silent period (iSP to determine the onset latency and the duration of transcallosal inhibition (i.e., LTI and DTI. Analysis of hemispheric variations in measures of corticospinal excitability revealed no major asymmetries in relation to degrees of laterality or handedness, with the exception of a rightward increase in rMTs in the LH group. Similarly, no clear asymmetries were found when looking at hemispheric variations in measures of transcallosal inhibition. However, a large group effect was detected for LTI measures, which were found to be significantly shorter in the MH group than in either the LH or RH group. MH participants also tended to show longer DTI than the other participants. Further inspection of overall variations in LTI and DTI measures as a function of LQs revealed that both variables followed a non-linear relationship, which was best described by a 2(nd order polynomial function. Overall, these findings provide converging evidence for a link between mixed-handedness and more efficient

  5. Extensive Spinal Decussation and Bilateral Termination of Cervical Corticospinal Projections in Rhesus Monkeys

    Science.gov (United States)

    Rosenzweig, Ephron S.; Brock, John H.; Culbertson, Maya D.; Lu, Paul; Moseanko, Rod; Edgerton, V. Reggie; Havton, Leif A.; Tuszynski, Mark H.

    2009-01-01

    To examine neuroanatomical mechanisms underlying fine motor control of the primate hand, adult Rhesus monkeys underwent injections of biotinylated dextran amine (BDA) into the right motor cortex. Spinal axonal anatomy was examined using detailed serial-section reconstruction and modified stereological quantification. 87% of corticospinal tract (CST) axons decussated in the medullary pyramids and descended through the contralateral dorsolateral tract of the spinal cord. 11% of CST axons projected through the dorsolateral CST ipsilateral to the hemisphere of origin, and 2% of axons projected through the ipsilateral ventromedial CST. Notably, corticospinal axons decussated extensively across the spinal cord midline. Remarkably, nearly two-fold more CST axons decussated across the cervical spinal cord midline (~12,000 axons) than were labeled in all descending components of the CST (~6,700 axons). These findings suggest that CST axons extend multiple segmental collaterals. Furthermore, serial-section reconstructions revealed that individual axons descending in either the ipsilateral or contralateral dorsolateral CST can: 1) terminate in the gray matter ipsilateral to the hemisphere of origin; 2) terminate in the gray matter contralateral to the hemisphere of origin; or 3) branch in the spinal cord and terminate on both sides of the spinal cord. These results reveal a previously unappreciated degree of bilaterality and complexity of corticospinal projections in the primate spinal cord. This bilaterality is more extensive than that of the rat CST, and may resemble human CST organization. Thus, augmentation of sprouting of these extensive bilateral CST projections may provide a novel target for enhancing recovery after spinal cord injury. PMID:19125408

  6. Encoding of Forelimb Forcesby Corticospinal Tract Activity in the Rat

    Directory of Open Access Journals (Sweden)

    Yi eGuo

    2014-05-01

    Full Text Available In search of a solution to the long standing problems encountered in traditional brain computer interfaces (BCI, the lateral descending tracts of the spinal cord present an alternative site for taping into the volitional motor signals. Due to the convergence of the cortical outputs into a final common pathway in the descending tracts of the spinal cord, neural interfaces with the spinal cord can potentially acquire signals richer with volitional information in a smaller anatomical region. The main objective of this study was to evaluate the feasibility of extracting motor control signals from the corticospinal tract (CST of the rat spinal cord. Flexible substrate, multi-electrode arrays (MEA were implanted in the CST of rats trained for a lever pressing task. This novel use of flexible substrate MEAs allowed recording of CST activity in behaving animals for up to three weeks with the current implantation technique. Time-frequency and principal component analyses (PCA were applied to the neural signals to reconstruct isometric forelimb forces. Computed regression coefficients were then used to predict isometric forces in additional trials. The correlation between measured and predicted forces in the vertical direction averaged across six animals was 0.67 and R-squared value was 0.44. Force regression in the horizontal directions was less successful, possibly due to the small amplitude of forces. Neural signals above and near the high gamma band made the largest contributions to prediction of forces. The results of this study support the feasibility of a spinal cord computer interface (SCCI for generation of command signals in paralyzed individuals.

  7. Brushless DC Motor Control System Design Based on DSP2812

    Directory of Open Access Journals (Sweden)

    Wei Min

    2016-01-01

    Full Text Available By comparison various control methods currently for permanent magnet brushless DC motor, on the basis of motor principle analysis, a current smallest and most real-time all-digital rare earth permanent magnet brushless DC motor control system is designed. The high-speed digital signal processor DSP2812 is applied as the main control unit. The fuzzy PID control algorithm is used to control rectifier regulator and speed, which the speed and current is double closed loop in the system. The principle of control system, control strategy and software is analyzed in this paper. The system has some features such as less overshoot, rapid response speed, good performance of anti-jamming, simple structure, high control precision, flexible in changing control policies and so on. Validity of the design is verified by prototype test.

  8. Long-lasting contralateral motor cortex excitability is increased by unilateral hand movement that triggers electrical stimulation of opposite homologous muscles.

    Science.gov (United States)

    Schmidt, Matthew W; Hinder, Mark R; Summers, Jeffery J; Garry, Michael I

    2011-01-01

    Long-term changes in the motor cortex can be induced by practicing motor tasks with simultaneous application of peripheral nerve stimulation. This combination may augment motor rehabilitation after stroke but has been used primarily during contraction of the affected hand. The authors tested the effect of a right hand movement that electrically stimulated left hand contraction on right motor cortex excitability. Three tasks were used in 15 healthy subjects--a motor and stimulation task (MS(task)), stimulation only task (S(task)), and motor only task (M(task)). The MS(task) consisted of isometric thumb abduction of the right hand that triggered paired electrical stimulation of the left abductor pollicis brevis (APB) and first dorsal interosseus (FDI) motor points. The S(task) was performed 1 week later and matched the stimulation received in the MS(task). The M(task) was performed as a control. Transcranial magnetic stimulation applied to the right motor cortex assessed corticospinal excitability, short latency intracortical inhibition, and intracortical facilitation of the FDI and APB before, immediately after, and 30 minutes after task performance. Corticospinal excitability increased in the FDI and APB following the MS(task) but not following the S(task) or M(task). The increased excitability present 30 minutes after the MS(task) also correlated with excitability measures recorded 1 week later. A bilateral motor and electrical stimulation task can drive persistent adaptation within the corticospinal system. Hemiplegic subjects who have poor voluntary movement of the affected hand may be able to contract the unaffected hand to activate and train homologous movements.

  9. Subcortical frontal lesions on MRI in patients with motor neurone disease

    Energy Technology Data Exchange (ETDEWEB)

    Andreadou, E.; Sgouropoulos, P.; Varelas, P.; Papageorgiou, C. [Eginition Hospital, Athens (Greece); Gouliamos, A. [Department of Radiology, CT/MRI Unit, Areteion Hospital, University of Athens (Greece)

    1998-05-01

    MRI was performed in 32 patients with motor neurone disease (26 men and 6 women, aged 40-77 years) and in a control group of 21 subjects. Of the patients studied, 19 had definite and 11 probable amyotrophic lateral sclerosis (ALS) and two had progressive bulbar palsy. In 10 patients there were asymmetrical bilateral foci of increased signal intensity on proton-density and T{sub 2}-weighted images, confined to the white matter. Two patients had only cortical frontal atrophy and slightly increased ventricular size, whereas 20 had normal MRI. The focal lesions were not confined to corticospinal tracts, but were also observed in subcortical frontal areas. While the lesions along the corticospinal tracts correspond to pyramidal tract degeneration, the subcortical foci correlate with degeneration of the frontal bundles and indicate generalised involvement of the central nervous system. (orig.) With 3 figs., 2 tabs., 25 refs.

  10. Practical Curriculum Design Based on Food Motoring System of PLC

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2015-03-01

    Full Text Available The study designed a kind of stepping food motoring control system based on PLC and touch screen, complete the secondary design and renovation based on PLC technology. According to the trend that the PLC new technology is widely and deeply applied into modern food industrial production, combining students electrician, maintenance electrician basic skill training needs to make a reformation of the food motoring system of student training curriculum. This system has simple structure, stable performance, economic value, outstanding using effect, remarkable specific design example and expected effect.

  11. Developmental kinesiology: three levels of motor control in the assessment and treatment of the motor system.

    Science.gov (United States)

    Kobesova, Alena; Kolar, Pavel

    2014-01-01

    Three levels of sensorimotor control within the central nervous system (CNS) can be distinguished. During the neonatal stage, general movements and primitive reflexes are controlled at the spinal and brain stem levels. Analysis of the newborn's spontaneous general movements and the assessment of primitive reflexes is crucial in the screening and early recognition of a risk for abnormal development. Following the newborn period, the subcortical level of the CNS motor control emerges and matures mainly during the first year of life. This allows for basic trunk stabilization, a prerequisite for any phasic movement and for the locomotor function of the extremities. At the subcortical level, orofacial muscles and afferent information are automatically integrated within postural-locomotor patterns. Finally, the cortical (the highest) level of motor control increasingly becomes activated. Cortical control is important for the individual qualities and characteristics of movement. It also allows for isolated segmental movement and relaxation. A child with impaired cortical motor control may be diagnosed with developmental dyspraxia or developmental coordination disorder. Human ontogenetic models, i.e., developmental motor patterns, can be used in both the diagnosis and treatment of locomotor system dysfunction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Damage to the medial motor system in stroke patients with motor neglect

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    Raffaella eMigliaccio

    2014-06-01

    Full Text Available Background and objectives. Motor neglect (MN is a clinically important condition whereby patients with unilateral brain lesions fail to move their contralateral limbs, despite normal muscle strength, reflexes, and sensation. MN has been associated with various lesion sites, including the parietal and frontal cortex, the internal capsule, the lenticulostriate nuclei, and the thalamus. In the present study, we explored the hypothesis that MN depends on a dysfunction of the medial motor system by performing a detailed anatomical analysis in four patients with MN.Methods. Ten patients participated in the study: four with MN, four with left visual neglect but without MN, and three patients with left hemiplegia without MN. We used specific scales for clinical and neuropsychological assessment. We drew the lesion borders directly onto the original brain images of each patient, and plotted the lesions on anatomical atlases for grey and white matter. Results. Lesion locations were highly heterogeneous in our MN patients, and included frontal and parietal sites, basal ganglia and white matter. The only consistently damaged structure across all MN patients was the cingulum bundle, a major pathway of the medial motor system important for motor initiative, and a key connection with limbic structures crucial for motivational aspects of actions. Three MN patients with additional damage to lateral fronto-parietal networks had also signs of contralesional visual neglect. The cingulum bundle was intact in all the control patients with visual neglect or hemiplegia.Conclusions. Cingulum damage may induce MN through unilateral dysfunction of the medial motor system. Additional lateral fronto-parietal dysfunction can result in the association with visual neglect.

  13. A Transformerless Medium Voltage Multiphase Motor Drive System

    Directory of Open Access Journals (Sweden)

    Dan Wang

    2016-04-01

    Full Text Available A multiphase motor has several major advantages, such as high reliability, fault tolerance, and high power density. It is a critical issue to develop a reliable and efficient multiphase motor drive system. In this paper, a transformerless voltage source converter-based drive system for a medium-voltage (MV multiphase motor is proposed. This drive converter employs cascaded H-bridge rectifiers loaded by H-bridge inverters as the interface between the grid and multiphase motor. The cascaded H-bridge rectifier technique makes the drive system able to be directly connected to the MV grid without the phase-shifting transformer because it can offset the voltage level gap between the MV grid and the semiconductor devices, provide near-sinusoidal AC terminal voltages without filters, and draw sinusoidal line current from the grid. Based on a digital signal processor (DSP, a complete improved Phase Disposition Pulse Width Modulation (PD-PWM method is developed to ensure the individual DC-link capacitor voltage balancing for enhancing the controllability and limiting the voltage and power stress on the H-bridge cells. A downscaled prototype is designed and developed based on a nine-phase motor. The experimental results verify the excellent performances of the proposed drive system and control strategy in steady-state and variant-frequency startup operations.

  14. Speed Control of Induction Motor Using PLC and SCADA System

    Directory of Open Access Journals (Sweden)

    Ayman Seksak Elsaid,

    2016-01-01

    Full Text Available Automation or automatic control is the use of various control systems for operating equipment such as machinery, processes in factories, boilers and heat-treating ovens, switching in telephone networks, steering and stabilization of ships, aircraft and other applications with minimal or reduced human intervention. Some processes have been completely automated. The motor speed is controlled via the driver as an open loop control. To make a more precise closed loop control of motor speed we will use a tachometer to measure the speed and feed it back to the PLC, which compares to the desired value and take a control action, then the signal is transferred to the motor – via driver – to increase / decrease the speed. We will measure the speed of the motor using an incremental rotary encoder by adjusting parameters (PLC, driver and also we need to reduce the overall cost of the system. Our control system will be held using the available Siemens PLC. In addition, we will monitor motor parameters via SCADA system.

  15. Induction Motors Most Efficient Operation Points in Pumped Storage Systems

    DEFF Research Database (Denmark)

    Busca-Forcos, Andreea; Marinescu, Corneliu; Busca, Cristian

    2015-01-01

    efficiency is desired especially when operating with renewable energy systems, which present low energy conversion factor (up to 50% - performance coefficient for wind turbines, and efficiency up to 40% for photovoltaic systems). In this paper the most efficient operation points of the induction motors...

  16. Kinesio-Taping Application and Corticospinal Excitability at the Ankle Joint

    Science.gov (United States)

    Tremblay, Francois; Karam, Siobhan

    2015-01-01

    Context Physiotherapists and athletic trainers often use Kinesio Taping (KT) to prevent and treat musculoskeletal injuries in athletes, yet evidence about its effects on neuromuscular performance is conflicting. Objective To investigate the influence of a KT application directed at the ankle joint on measures of corticospinal excitability with transcranial magnetic stimulation. Design Controlled laboratory study. Setting Research laboratory. Patients or Other Participants Twelve healthy young women (age = 23.1 ± 1.9 years; range, 19–26 years). Intervention(s) Participants were tested under no-tape and KT conditions according to a random sequence order. The KT was applied to the skin overlying the dorsiflexor and plantar-flexor muscles of the ankle. Main Outcome Measure(s) We assessed changes in the amplitude of motor-evoked potentials elicited at rest and during movement and changes in the silent period and background muscle activity during movement. Results Taping conditions had no effect on motor-evoked potential amplitude at rest or during movement or on the silent-period duration and background muscle activity. Conclusions Our results concur with other recent reports, showing KT applications have little influence at the neuromuscular level. Alterations in sensory feedback ascribed to elastic taping are likely insufficient to modulate corticospinal excitability in a functionally meaningful manner. PMID:26090708

  17. Decreased Corticospinal Excitability after the Illusion of Missing Part of the Arm.

    Science.gov (United States)

    Kilteni, Konstantina; Grau-Sánchez, Jennifer; Veciana De Las Heras, Misericordia; Rodríguez-Fornells, Antoni; Slater, Mel

    2016-01-01

    Previous studies on body ownership illusions have shown that under certain multimodal conditions, healthy people can experience artificial body-parts as if they were part of their own body, with direct physiological consequences for the real limb that gets 'substituted.' In this study we wanted to assess (a) whether healthy people can experience 'missing' a body-part through illusory ownership of an amputated virtual body, and (b) whether this would cause corticospinal excitability changes in muscles associated with the 'missing' body-part. Forty right-handed participants saw a virtual body from a first person perspective but for half of them the virtual body was missing a part of its right arm. Single pulse transcranial magnetic stimulation was applied before and after the experiment to left and right motor cortices. Motor evoked potentials (MEPs) were recorded from the first dorsal interosseous (FDI) and the extensor digitorum communis (EDC) of each hand. We found that the stronger the illusion of amputation and arm ownership, the more the reduction of MEP amplitudes of the EDC muscle for the contralateral sensorimotor cortex. In contrast, no association was found for the EDC amplitudes in the ipsilateral cortex and for the FDI amplitudes in both contralateral and ipsilateral cortices. Our study provides evidence that a short-term illusory perception of missing a body-part can trigger inhibitory effects on corticospinal pathways and importantly in the absence of any limb deafferentation or disuse.

  18. Decreased corticospinal excitability after the illusion of missing part of the arm

    Directory of Open Access Journals (Sweden)

    Konstantina eKilteni

    2016-04-01

    Full Text Available Previous studies on body ownership illusions have shown that under certain multimodal conditions, healthy people can experience artificial body-parts as if they were part of their own body, with direct physiological consequences for the real limb that gets ‘substituted’. In this study we wanted to assess (a whether healthy people can experience ‘missing’ a body-part through illusory ownership of an amputated virtual body, and (b whether this would cause corticospinal excitability changes in muscles associated with the ‘missing’ body-part. Forty right-handed participants saw a virtual body from a first person perspective but for half of them the virtual body was missing a part of its right arm. Single pulse transcranial magnetic stimulation was applied before and after the experiment to left and right motor cortices. Motor evoked potentials (MEPs were recorded from the first dorsal interosseous (FDI and the extensor digitorum communis (EDC of each hand. We found that the stronger the illusion of amputation and arm ownership, the more the reduction of MEP amplitudes of the EDC muscle for the contralateral sensorimotor cortex. In contrast, no association was found for the EDC amplitudes in the ipsilateral cortex and for the FDI amplitudes in both contralateral and ipsilateral cortices. Our study provides evidence that a short-term illusory perception of missing a body-part can trigger inhibitory effects on corticospinal pathways and importantly in the absence of any limb deafferentation or disuse.

  19. Decreased Corticospinal Excitability after the Illusion of Missing Part of the Arm

    Science.gov (United States)

    Kilteni, Konstantina; Grau-Sánchez, Jennifer; Veciana De Las Heras, Misericordia; Rodríguez-Fornells, Antoni; Slater, Mel

    2016-01-01

    Previous studies on body ownership illusions have shown that under certain multimodal conditions, healthy people can experience artificial body-parts as if they were part of their own body, with direct physiological consequences for the real limb that gets ‘substituted.’ In this study we wanted to assess (a) whether healthy people can experience ‘missing’ a body-part through illusory ownership of an amputated virtual body, and (b) whether this would cause corticospinal excitability changes in muscles associated with the ‘missing’ body-part. Forty right-handed participants saw a virtual body from a first person perspective but for half of them the virtual body was missing a part of its right arm. Single pulse transcranial magnetic stimulation was applied before and after the experiment to left and right motor cortices. Motor evoked potentials (MEPs) were recorded from the first dorsal interosseous (FDI) and the extensor digitorum communis (EDC) of each hand. We found that the stronger the illusion of amputation and arm ownership, the more the reduction of MEP amplitudes of the EDC muscle for the contralateral sensorimotor cortex. In contrast, no association was found for the EDC amplitudes in the ipsilateral cortex and for the FDI amplitudes in both contralateral and ipsilateral cortices. Our study provides evidence that a short-term illusory perception of missing a body-part can trigger inhibitory effects on corticospinal pathways and importantly in the absence of any limb deafferentation or disuse. PMID:27148005

  20. Continuous growth of the motor system in the axolotl

    Energy Technology Data Exchange (ETDEWEB)

    Holder, N.; Clarke, J.D.; Stephens, N.; Wilson, S.W.; Orsi, C.; Bloomer, T.; Tonge, D.A. (King' s College, London (England))

    1991-01-22

    During growth of the axolotl, motor neurons, and muscle fibres are added to the motor system. By double labelling neurons with tritiated thymidine and retrogradely transported HRP, we show that some motor neurons are born at postembryonic stages. Further analysis of motor neurons with the aid of HRP reveals this population of newly born cells relatively frequently in small (5-7 cm long) axolotls, but only rarely in large (7-13 cm long) axolotls. Evidence is presented that suggests that these immature cells are in the process of migrating from close to the ependyma out to the ventral horn. HRP transport also reveals growth cones of advancing axons within spinal nerves in animals up to 6 cm in length. Cell counts by light and electron microscopic methods show that muscle fibres are generated throughout larval life in the iliotibialis, a typical limb muscle. This analysis provides data consistent with the notion that new muscle fibres are added from a localised growth zone situated at the superficial edge of the muscle. These results are discussed in terms of the correlation between continuous growth of the motor system and the ability of the axolotl to functionally repair lesions to the peripheral nervous system.

  1. Information about the weight of grasped objects from vision and internal models interacts within the primary motor cortex.

    Science.gov (United States)

    Loh, Morrison N; Kirsch, Louise; Rothwell, John C; Lemon, Roger N; Davare, Marco

    2010-05-19

    When grasping and lifting different objects, visual cues and previously acquired knowledge enable us to prepare the upcoming grasp by scaling the fingertip forces according to the actual weight of the object. However, when no visual information is available, the weight of the object has to be predicted based on information learned from previous grasps. Here, we investigated how changes in corticospinal excitability (CSE) and grip force scaling depend on the presence of visual cues and the weight of previously lifted objects. CSE was assessed by delivering transcranial magnetic stimulation (TMS) at different times before grasp of the object. In conditions in which visual information was not provided, the size of motor evoked potentials (MEP) was larger when the object lifted was preceded by a heavy relative to a light object. Interestingly, the previous lift also affected MEP amplitude when visual cues about object weight were available but only in the period immediately after object presentation (50 ms); this effect had already declined for TMS delivered 150 ms after presentation. In a second experiment, we demonstrated that these CSE changes are used by the motor system to scale grip force. This suggests that the corticospinal system stores a "sensorimotor memory" of the grasp of different objects and relies on this memory when no visual cues are present. Moreover, visual information about weight interacts with this stored representation and allows the corticospinal system to switch rapidly to a different model of predictive grasp control.

  2. Understanding mirror neurons: evidence for enhanced corticospinal excitability during the observation of transitive but not intransitive hand gestures.

    Science.gov (United States)

    Enticott, Peter G; Kennedy, Hayley A; Bradshaw, John L; Rinehart, Nicole J; Fitzgerald, Paul B

    2010-07-01

    Putative measures of mirror neuron activity suggest that mirror neurons respond preferentially to biological motion, but it remains unclear whether enhanced cortical activity occurs during the observation of any behaviour, or whether that behaviour needs to be associated with a particular object or goal. Forty-three healthy adults completed a transcranial magnetic stimulation (TMS) experiment that assessed corticospinal excitability while viewing intransitive and transitive hand gestures (compared with the presentation of a static hand). Visual presentations were designed to control for motoric and stimulus properties. A significant increase in corticospinal excitability (putatively reflecting mirror neuron activation) was seen only during the observation of transitive behaviour. These findings are consistent with the notion that human hand-related mirror neurons are sensitive to object- and goal-directed behaviour, rather than biological motion per se. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  3. Congenital absence of corticospinal tract does not severely affect plastic changes of the developing postnatal spinal cord.

    Science.gov (United States)

    Huang, L; Xian, Q; Shen, N; Shi, L; Qu, Y; Zhou, L

    2015-08-20

    The arrival and refinement of corticospinal afferents are likely to influence the maturation of the spinal cord and sensory-motor networks. To understand this better, we studied the revision of monosynaptic muscle afferents, the expression of activity-related genes, neurotrophins and their receptors in the cervical spinal cord from postnatal day (P) 0 to 21. We compared control and Celsr3|Emx1 mice, in which corticospinal axons never develop. The corticospinal tract (CST), labeled by anti-protein kinase C gamma (PKCγ) antibody in the dorsal funiculus, increased gradually in the control, but was never visible in the mutant. Using anti-parvalbumin and choline acetyltransferase double immunostaining, close contacts between proprioceptive afferent fibers and spinal motor neurons appeared at P0 and were gradually eliminated thereafter, with no difference between control and mutant mice. In both genotypes, the number of parvalbumin-positive interneurons increased similarly from P7 to P21, and a comparable upregulation of c-Jun protein was seen at P7. Contrary to control samples, in which ciliary neurotrophic factor (CNTF) protein levels increased from P0 to P7 and gradually decreased after P14, CNTF concentrations were time-invariant in mutant samples. The dynamic profile of neurotrophin-3 (NT3) expression was also moderately affected in mutant mice. In control spinal cord, NT3 was increased at P7 and decreased at P14, but remained more stable in mutant samples. In contrast, expression profiles of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase (Trk) B, TrkC, p75 neurotrophin receptor (p75(NTR)) and glial cell-line-derived neurotrophic factor (GDNF) were similar in both genotypes. In conclusion, with the possible exception of CNTF and NT3 expression, most events that accompany maturation of the spinal cord appear largely independent of corticospinal inputs.

  4. Assessment of the corticospinal tract alterations before and after resection of brainstem lesions using Diffusion Tensor Imaging (DTI) and tractography at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Kovanlikaya, Ilhami, E-mail: ilk2002@med.cornell.edu [Department of Radiology, Weill Cornell Medical College, New York, NY (United States); Firat, Zeynep [Department of Radiology, Yeditepe University Hospital, Istanbul (Turkey); Kovanlikaya, Arzu [Department of Radiology, Weill Cornell Medical College, New York, NY (United States); Ulug, Aziz M. [Department of Radiology, Weill Cornell Medical College, New York, NY (United States); Department of Biomedical Engineering, Yeditepe University, Istanbul (Turkey); Cihangiroglu, M. Mutlu [Department of Radiology, Yeditepe University Hospital, Istanbul (Turkey); John, Majnu [Department of Public Health, Division of Biostatistics and Epidemiology, Weill Cornell Medical College, New York, NY (United States); Bingol, Canan Aykut; Ture, Ugur [Institute of Neurological Sciences, Yeditepe University Hospital, Istanbul (Turkey)

    2011-03-15

    The purpose of the study was to investigate the role of Diffusion Tensor Imaging (DTI) and Diffusion Tensor Tractography (DTT) on the corticospinal tract alterations due to space occupying lesions in the brainstem before and after surgical resection. Pre- and post-surgical DTI data were acquired in 14 patients undergoing surgical resection of brainstem lesions. Patterns of corticospinal tract (CST) alteration on DTT were compared with the neurological exams of the patients pre- and post-operatively. DTT, especially in 3D movie format, seemed very helpful for evaluating the relationship of the lesions with the corticospinal tracts for surgical approach. None of the patients developed additional motor deficit related to surgery except one patient who presented with cerebellar ataxia after surgery. All of the patients with normal CST on DTT presented without motor deficit on neurological exam. The sensitivity, specificity, positive predictive and negative predictive values of DTT before surgery were 100%, 63.6%, 42.9% and 100%, and the corresponding values after surgery were 100%, 96%, 75% and 100% respectively. Although it has low specificity before surgery, DTT is a potentially useful technique in evaluating the effects of brainstem lesions and surgical resection on the relevant corticospinal tracts with high negative predictive value and higher specificity after surgery.

  5. Homeostatic-like plasticity of the primary motor hand area is impaired in focal hand dystonia.

    Science.gov (United States)

    Quartarone, Angelo; Rizzo, Vincenzo; Bagnato, Sergio; Morgante, Francesca; Sant'Angelo, Antonino; Romano, Marcello; Crupi, Domenica; Girlanda, Paolo; Rothwell, John C; Siebner, Hartwig R

    2005-08-01

    The excitability of inhibitory circuits in patients with writer's cramp is reduced at multiple levels within the sensorimotor system, including the primary motor hand area (M1). Although this may play a major role in the pathophysiology of writer's cramp, it is still unclear what factors may cause the imbalance between inhibition and excitation to arise. One possibility is that homeostatic mechanisms that keep cortical excitability within a normal physiological range are impaired. In eight patients with writer's cramp and eight healthy age-matched controls, we combined low-frequency repetitive transcranial magnetic stimulation (rTMS) with transcranial direct current stimulation (TDCS) to probe regional homeostatic plasticity of the left M1. Confirming our previous study (Siebner et al., J Neurosci 2004; 24: 3379-85), 'facilitatory' preconditioning of the M1 with anodal TDCS enhanced the inhibitory effect of subsequent 1 Hz rTMS on corticospinal excitability. Conversely, 'inhibitory' preconditioning with cathodal TDCS reversed the after effect of 1 Hz rTMS, producing an increase in corticospinal excitability. The results were quite different in patients with writer's cramp. Following preconditioning with TDCS, 1 Hz rTMS induced no consistent changes in corticospinal excitability, indicating a loss of the normal 'homeostatic' response pattern. In addition, the normal inhibitory effect of preconditioning with cathodal TDCS was absent. The present data suggest that homeostatic mechanisms that stabilize excitability levels within a useful dynamic range are impaired in patients with writer's cramp. We propose that a faulty homeostatic response to acute increases in corticospinal excitability favours maladaptive motor plasticity. The role of homeostatic-like plasticity in the pathophysiology of task-specific dystonias warrants further study.

  6. Control systems are General Motors' biggest energy saver

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    In 1978, General Motors Corp. used almost 3% less energy than it did in 1972, even though production had increased about 25%. Most of the savings are the result of improved technology and design changes in buildings, equipment, and processes. Computerized energy management control systems are now in operation or being installed in 78 GM buildings.

  7. Practical Modeling and Comprehensive System Identification of a BLDC Motor

    Directory of Open Access Journals (Sweden)

    Changle Xiang

    2015-01-01

    Full Text Available The aim of this paper is to outline all the steps in a rigorous and simple procedure for system identification of BLDC motor. A practical mathematical model for identification is derived. Frequency domain identification techniques and time domain estimation method are combined to obtain the unknown parameters. The methods in time domain are founded on the least squares approximation method and a disturbance observer. Only the availability of experimental data for rotor speed and armature current are required for identification. The proposed identification method is systematically investigated, and the final identified model is validated by experimental results performed on a typical BLDC motor in UAV.

  8. Improvement the DTC system for electric vehicles induction motors

    Directory of Open Access Journals (Sweden)

    Arif Ali

    2010-01-01

    Full Text Available A three-phase squirrel-cage induction motor is used as a propulsion system of an electric vehicle (EV. Two different control methods have been designed. The first is based on the conventional DTC Scheme adapted for three level inverter. The second is based on the application of fuzzy logic controller to the DTC scheme. The motor is controlled at different operating conditions using a FLC based DTC technique. In the simulation the novel proposed technique reduces the torque and current ripples. The EV dynamics are taken into account.

  9. Favouritism in the motor system: social interaction modulates action simulation.

    Science.gov (United States)

    Kourtis, Dimitrios; Sebanz, Natalie; Knoblich, Günther

    2010-12-23

    The ability to anticipate others' actions is crucial for social interaction. It has been shown that this ability relies on motor areas of the human brain that are not only active during action execution and action observation, but also during anticipation of another person's action. Recording electroencephalograms during a triadic social interaction, we assessed whether activation of motor areas pertaining to the human mirror-neuron system prior to action observation depends on the social relationship between the actor and the observer. Anticipatory motor activation was stronger when participants expected an interaction partner to perform a particular action than when they anticipated that the same action would be performed by a third person they did not interact with. These results demonstrate that social interaction modulates action simulation.

  10. Direct and crossed effects of somatosensory stimulation on neuronal excitability and motor performance in humans

    NARCIS (Netherlands)

    Veldman, M. P.; Maffiuletti, N. A.; Hallett, M.; Zijdewind, I.; Hortobagyi, T.

    2014-01-01

    This analytic review reports how prolonged periods of somatosensory electric stimulation (SES) with repetitive transcutaneous nerve stimulation can have 'direct' and 'crossed' effects on brain activation, corticospinal excitability, and motor performance. A review of 26 studies involving 315 healthy

  11. Improving Motor and Drive System Performance – A Sourcebook for Industry

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-02-01

    This sourcebook outlines opportunities to improve motor and drive systems performance. The sourcebook is divided into four main sections: (1) Motor and Drive System Basics: Summarizes important terms, relationships, and system design considerations relating to motor and drive systems. (2) Performance Opportunity Road Map: Details the key components of well-functioning motor and drive systems and opportunities for energy performance opportunities. (3) Motor System Economics: Offers recommendations on how to propose improvement projects based on corporate priorities, efficiency gains, and financial payback periods. (4) Where to Find Help: Provides a directory of organizations associated with motors and drives, as well as resources for additional information, tools, software, videos, and training opportunities.

  12. Paired associative transcranial alternating current stimulation increases the excitability of corticospinal projections in humans.

    Science.gov (United States)

    McNickle, Emmet; Carson, Richard G

    2015-04-01

    Many types of non-invasive brain stimulation alter corticospinal excitability (CSE). Paired associative stimulation (PAS) has attracted particular attention as its effects ostensibly adhere to Hebbian principles of neural plasticity. In prototypical form, a single electrical stimulus is directed to a peripheral nerve in close temporal contiguity with transcranial magnetic stimulation delivered to the contralateral primary motor cortex (M1). Repeated pairing of the two discrete stimulus events (i.e. association) over an extended period either increases or decreases the excitability of corticospinal projections from M1, contingent on the interstimulus interval. We studied a novel form of associative stimulation, consisting of brief trains of peripheral afferent stimulation paired with short bursts of high frequency (≥80 Hz) transcranial alternating current stimulation (tACS) over contralateral M1. Elevations in the excitability of corticospinal projections to the forearm were observed for a range of tACS frequency (80, 140 and 250 Hz), current (1, 2 and 3 mA) and duration (500 and 1000 ms) parameters. The effects were at least as reliable as those brought about by PAS or transcranial direct current stimulation. When paired with tACS, muscle tendon vibration also induced elevations of CSE. No such changes were brought about by the tACS or peripheral afferent stimulation alone. In demonstrating that associative effects are expressed when the timing of the peripheral and cortical events is not precisely circumscribed, these findings suggest that multiple cellular pathways may contribute to a long term potentiation-type response. Their relative contributions will differ depending on the nature of the induction protocol that is used.

  13. Aberrant crossed corticospinal facilitation in muscles distant from a spinal cord injury.

    Directory of Open Access Journals (Sweden)

    Karen L Bunday

    Full Text Available Crossed facilitatory interactions in the corticospinal pathway are impaired in humans with chronic incomplete spinal cord injury (SCI. The extent to which crossed facilitation is affected in muscles above and below the injury remains unknown. To address this question we tested 51 patients with neurological injuries between C2-T12 and 17 age-matched healthy controls. Using transcranial magnetic stimulation we elicited motor evoked potentials (MEPs in the resting first dorsal interosseous, biceps brachii, and tibialis anterior muscles when the contralateral side remained at rest or performed 70% of maximal voluntary contraction (MVC into index finger abduction, elbow flexion, and ankle dorsiflexion, respectively. By testing MEPs in muscles with motoneurons located at different spinal cord segments we were able to relate the neurological level of injury to be above, at, or below the location of the motoneurons of the muscle tested. We demonstrate that in patients the size of MEPs was increased to a similar extent as in controls in muscles above the injury during 70% of MVC compared to rest. MEPs remained unchanged in muscles at and within 5 segments below the injury during 70% of MVC compared to rest. However, in muscles beyond 5 segments below the injury the size of MEPs increased similar to controls and was aberrantly high, 2-fold above controls, in muscles distant (>15 segments from the injury. These aberrantly large MEPs were accompanied by larger F-wave amplitudes compared to controls. Thus, our findings support the view that corticospinal degeneration does not spread rostral to the lesion, and highlights the potential of caudal regions distant from an injury to facilitate residual corticospinal output after SCI.

  14. Volitional muscle activity paired with transcranial magnetic stimulation increases corticospinal excitability

    Directory of Open Access Journals (Sweden)

    Matthew A Edwardson

    2015-01-01

    Full Text Available Studies of activity-dependent stimulation in non-human primates suggest that pairing each instance of volitional muscle activity with immediate intracortical stimulation causes long-term-potentiation-like effects. This technique holds promise for clinical rehabilitation, yet few investigators have tested activity-dependent stimulation in human subjects. In addition, no one has studied activity-dependent stimulation on the cortical representation for two separate target muscles in human subjects. We hypothesized that 40 min of transcranial magnetic stimulation (TMS triggered from ballistic muscle activity at a mean repetition rate of 1 Hz would cause greater increases in corticospinal excitability than TMS-cued muscle activity, and that these changes would be specific to the muscle of study. Ten healthy human subjects participated in 4 separate sessions in this crossover study: (1 visually cued volitional activation of the abductor pollicis brevis (APB muscle triggering TMS (APB-Triggered TMS, (2 volitional activation of APB in response to TMS delivered from a recording of the prior APB-Triggered TMS session (TMS-Cued APB, (3 visually cued volitional activation of the extensor digitorum (ED triggering TMS (ED-Triggered TMS, and (4 volitional activation of ED in response to TMS delivered from a recording of the prior ED-Triggered TMS session (TMS-Cued ED. Contrary to our hypothesis, we discovered evidence of increased corticospinal excitability for all conditions as measured by change in area of the motor evoked potential. We conclude that single TMS pulses paired either before or after muscle activity may increase corticospinal excitability and that further studies are needed to clarify the optimal time window for inducing neural plasticity with activity-dependent stimulation. These findings will inform the design of future activity-dependent stimulation protocols for clinical rehabilitation.

  15. Changes in tibialis anterior corticospinal properties after acute prolonged muscle vibration.

    Science.gov (United States)

    Farabet, Adrien; Souron, Robin; Millet, Guillaume Y; Lapole, Thomas

    2016-06-01

    Prolonged local vibration is known to impair muscle performance. While involved mechanisms were previously evidenced at the spinal level, changes at the cortical level were also hypothesized. The aims of the present study were to investigate the effects of 30 min of 100-Hz tibialis anterior muscle vibration on force production capacities and to further identify the respective changes in spinal loop properties, descending voluntary drive and corticospinal properties. Thirteen subjects were tested before and after a vibration condition, and before and after a resting control condition. Maximal voluntary contraction (MVC) in dorsiflexion was measured. Transcranial magnetic stimulation was superimposed during MVCs to assess cortical voluntary activation (VATMS), motor-evoked potential amplitude (MEP) and cortical silent period length (CSP). MEP and CSP were also measured during 50 and 75 % MVC contractions. Spinal excitability was investigated by mean of H-reflex. There were no vibration effects on MVC (p = 0.805), maximal EMG activity (p = 0.653), VATMS (p = 1), and CSP (p = 0.877). Vibration tended to decrease MEP amplitude (p = 0.117). H-reflex amplitude was depressed following vibration (p = 0.008). Dorsiflexion maximal force production capacities were unaffected by 30 min of tibialis anterior muscle vibration, despite spinal loop and corticospinal excitabilities being reduced. These findings suggest that acute prolonged vibration has the potential to modulate corticospinal excitability of lower limb muscles without a concomitant functional consequence.

  16. The United States industrial electric motor systems market opportunities assessment: Key results

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, M.; Olszewski, M.; Scheihing, P.

    1999-07-01

    This paper summarizes the findings of the US Industrial Electric Motor Systems Market Opportunities Assessment. The Market Assessment was sponsored by the US Department of Energy. The project's principal objectives were to create a detailed portrait of the inventory of motor systems currently in use in US industrial facilities, estimate motor system energy use and potential for energy savings. The research and analysis to support these objectives consisted primarily of on-site motor system inventories of a probability sample of 354 manufacturing facilities nationwide. In addition to characterizing the motor systems in use, the research effort also gathered detailed information on motor system management and purchasing practices. This paper presents key findings from the Market Assessment in regard to patterns of motor energy use, saturation of energy efficiency measures such as efficient motors and adjustable speed drives, and motor system purchase and maintenance practices.

  17. DECOUPLING CONTROL OF TWO MOTORS SYSTEM BASED ON NEURAL NETWORK INVERSE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Wang Deming; Ju Ping; Liu Guohai

    2004-01-01

    In accordance with the characteristics of two motors system, the united mathematic model of two-motors inverter system with v/f variable frequency speed-regulating is given. Two-motor inverter system can be decoupled by the neural network invert system, and changed into a sub-system of speed and a sub-system of tension. Multiple controllers are designed, and good results are obtained. The system has good static and dynamic performances and high anti-disturbance of load.

  18. Molecular motor assembly of a biomimetic system

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.

  19. Corticospinal excitability underlying digit force planning for grasping in humans.

    Science.gov (United States)

    Parikh, Pranav; Davare, Marco; McGurrin, Patrick; Santello, Marco

    2014-06-15

    Control of digit forces for grasping relies on sensorimotor memory gained from prior experience with the same or similar objects and on online sensory feedback. However, little is known about neural mechanisms underlying digit force planning. We addressed this question by quantifying the temporal evolution of corticospinal excitability (CSE) using single-pulse transcranial magnetic stimulation (TMS) during two reach-to-grasp tasks. These tasks differed in terms of the magnitude of force exerted on the same points on the object to isolate digit force planning from reach and grasp planning. We also addressed the role of intracortical circuitry within primary motor cortex (M1) by quantifying the balance between short intracortical inhibition and facilitation using paired-pulse TMS on the same tasks. Eighteen right-handed subjects were visually cued to plan digit placement at predetermined locations on the object and subsequently to exert either negligible force ("low-force" task, LF) or 10% of their maximum pinch force ("high-force" task, HF) on the object. We found that the HF task elicited significantly smaller CSE than the LF task, but only when the TMS pulse coincided with the signal to initiate the reach. This force planning-related CSE modulation was specific to the muscles involved in the performance of both tasks. Interestingly, digit force planning did not result in modulation of M1 intracortical inhibitory and facilitatory circuitry. Our findings suggest that planning of digit forces reflected by CSE modulation starts well before object contact and appears to be driven by inputs from frontoparietal areas other than M1.

  20. Motor systems energy efficiency supply curves: A methodology for assessing the energy efficiency potential of industrial motor systems

    Energy Technology Data Exchange (ETDEWEB)

    McKane, Aimee [Industrial Energy Analysis, Energy Analysis Department, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd. MS 90R4000, Berkeley, CA 94720 (United States); Hasanbeigi, Ali, E-mail: AHasanbeigi@lbl.gov [China Energy Group, Energy Analysis Department, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd. MS 90R4000, Berkeley, CA 94720 (United States)

    2011-10-15

    Motor-driven equipment accounts for approximately 60% of manufacturing final electricity use worldwide. A major barrier to effective policymaking, and to more global acceptance of the energy efficiency potential in industrial motor systems, is the lack of a transparent methodology for quantifying the magnitude and cost-effectiveness of these energy savings. This paper presents the results of groundbreaking analyses conducted for five countries and one region to begin to address this barrier. Using a combination of expert opinion and available data from the United States, Canada, the European Union, Thailand, Vietnam, and Brazil, bottom-up energy efficiency supply curve models were constructed to estimate the cost-effective electricity efficiency potentials and CO{sub 2} emission reduction for three types of motor systems (compressed air, pumping, and fan) in industry for the selected countries/region. Based on these analyses, the share of cost-effective electricity saving potential of these systems as compared to the total motor system energy use in the base year varies between 27% and 49% for pumping, 21% and 47% for compressed air, and 14% and 46% for fan systems. The total technical saving potential varies between 43% and 57% for pumping, 29% and 56% for compressed air, and 27% and 46% for fan systems. - Highlights: > Development of conservation supply curves for the industrial motor systems. > An innovative approach combining available aggregate country-level data with expert opinion. > Results show both cost-effective and technical potential for energy saving and their costs. > Policy implication of the results are briefly discussed.

  1. The Uniqueness of Speech among Motor Systems

    Science.gov (United States)

    Kent, Ray

    2004-01-01

    This paper considers evidence that the speech muscles are unique in their genetic, developmental, functional and phenotypical properties. The literature was reviewed using PubMed, ScienceDirect, ComDisDome and other literature-retrieval systems to identify studies reporting on the craniofacial and laryngeal muscles. Particular emphasis was given…

  2. Transcranial Magnetic Stimulation with Intermittent Theta Burst Stimulation Alters Corticospinal Output in Patients with Chronic Incomplete Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Hunter J. Fassett

    2017-08-01

    Full Text Available Intermittent theta burst stimulation (iTBS is intended primarily to alter corticospinal excitability, creating an attractive opportunity to alter neural output following incomplete spinal cord injury (SCI. This study is the first to assess the effects of iTBS in SCI. Eight individuals with chronic incomplete SCI were studied. Sham or real iTBS was delivered (to each participant over primary motor and somatosensory cortices in separate sessions. Motor-evoked potential (MEP recruitment curves were obtained from the flexor carpi radialis muscle before and after iTBS. Results indicate similar responses for iTBS to both motor and somatosensory cortex and reduced MEPs in 56.25% and increased MEPs in 25% of instances. Sham stimulation exceeded real iTBS effects in the remaining 18.25%. It is our opinion that observing short-term neuroplasticity in corticospinal output in chronic SCI is an important advance and should be tested in future studies as an opportunity to improve function in this population. We emphasize the need to re-consider the importance of the direction of MEP change following a single session of iTBS since the relationship between MEP direction and motor function is unknown and multiple sessions of iTBS may yield very different directional results. Furthermore, we highlight the importance of including sham control in the experimental design. The fundamental point from this pilot research is that a single session of iTBS is often capable of creating short-term change in SCI. Future sham-controlled randomized trials may consider repeat iTBS sessions to promote long-term changes in corticospinal excitability.

  3. Vulnerability of the medial frontal corticospinal projection accompanies combined lateral frontal and parietal cortex injury in rhesus monkey.

    Science.gov (United States)

    Morecraft, R J; Ge, J; Stilwell-Morecraft, K S; McNeal, D W; Hynes, S M; Pizzimenti, M A; Rotella, D L; Darling, W G

    2015-03-01

    Concurrent damage to the lateral frontal and parietal cortex is common following middle cerebral artery infarction, leading to upper extremity paresis, paresthesia, and sensory loss. Motor recovery is often poor, and the mechanisms that support or impede this process are unclear. Since the medial wall of the cerebral hemisphere is commonly spared following stroke, we investigated the spontaneous long-term (6 and 12 month) effects of lateral frontoparietal injury (F2P2 lesion) on the terminal distribution of the corticospinal projection (CSP) from intact, ipsilesional supplementary motor cortex (M2) at spinal levels C5 to T1. Isolated injury to the frontoparietal arm/hand region resulted in a significant loss of contralateral corticospinal boutons from M2 compared with controls. Specifically, reductions occurred in the medial and lateral parts of lamina VII and the dorsal quadrants of lamina IX. There were no statistical differences in the ipsilateral CSP. Contrary to isolated lateral frontal motor injury (F2 lesion), which results in substantial increases in contralateral M2 labeling in laminae VII and IX (McNeal et al. [2010] J. Comp. Neurol. 518:586-621), the added effect of adjacent parietal cortex injury to the frontal motor lesion (F2P2 lesion) not only impedes a favorable compensatory neuroplastic response but results in a substantial loss of M2 CSP terminals. This dramatic reversal of the CSP response suggests a critical trophic role for cortical somatosensory influence on spared ipsilesional frontal corticospinal projections, and that restoration of a favorable compensatory response will require therapeutic intervention. © 2014 Wiley Periodicals, Inc.

  4. A hybrid stepping motor system with dual CPU

    Institute of Scientific and Technical Information of China (English)

    高晗璎; 赵克; 孙力

    2004-01-01

    An indirect method of measuring the rotor position based on the magnetic reluctance variation is presented in the paper. A single-chip microprocessor 80C196KC is utilized to compensate the phase shift produeed by the process of position signals. At the same time, a DSP (Data Signal Processor) unit is used to realize the speed and current closed-loops of the hybrid stepping motor system. At last, experimental results show the control system has excellent static and dynamic characteristics.

  5. Magnification of starting torques of dc motors by maximum power point trackers in photovoltaic systems

    Science.gov (United States)

    Appelbaum, J.; Singer, S.

    1989-01-01

    A calculation of the starting torque ratio of permanent magnet, series, and shunt-excited dc motors powered by solar cell arrays is presented for two cases, i.e., with and without a maximum-power-point tracker (MPPT). Defining motor torque magnification by the ratio of the motor torque with an MPPT to the motor torque without an MPPT, a magnification of 3 for the permanent magnet motor and a magnification of 7 for both the series and shunt motors are obtained. The study also shows that all motor types are less sensitive to solar insolation variation in systems including MPPTs as compared to systems without MPPTs.

  6. Improving Mechanical Characteristics of Inverter-induction Motor Drive System

    Directory of Open Access Journals (Sweden)

    Hussein Sarhan

    2006-01-01

    Full Text Available An inverter-three-phase squirrel-cage induction motor drive system with improved mechanical characteristics is presented. The proposed system provides mechanical characteristics with constant maximum torque or increased maximum torque and reduced slip speed at frequencies below the nominal frequency. The control algorithm is based on the constant volts per hertz principle using two improvement techniques: keeping maximum torque constant or keeping magnetic flux constant. Performance analysis of the system under different operation conditions was provided. For this purpose, a standard state-space model of three-phase squirrel-cage induction motor, with respect to a synchronously rotating d-q reference frame was derived. The correctness and validity of the derived model of induction motor was verified. The inverter was considered as a static linear element and modeled through its input-output equation based on the modulation index. Three types of controllers were modeled, simulated and experimentally tested. The results show that both suggested control methods improve the system performance. The slip speed has been decreased and the starting torque and maximum torque have been increased. Controller with constant maximum torque can be used in drive systems working with constant load, while controller with constant flux can be used in drive systems working with constant power.

  7. Steerable motor systems in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Burton, B.

    1988-05-01

    Since their introduction to the Gulf of Mexico in September 1985, downhole steerable motor systems have been widely recognized for making major contributions to improved directional and horizontal drilling efficiency as well as the overall advancement of drilling technology. Some sources estimate this advanced technology can improve overall drilling productivity by 50 percent. Others foresee the day when future generations of the current systems will replace the rotary table as the primary drive mechanisms for the bit. While the technological issues are coming into better focus, less visible are the ripple effects of this innovation upon the market participants who supply traditional products and services complimentary to the drilling process. The purpose of this article is to provide an objective evaluation of the performance statistics of steerable motor systems to date in the Gulf of Mexico, thereby allowing for a greater understanding of the future market conditions that may develop with this emerging technology.

  8. Simulation of Field Oriented Control in Induction Motor Drive System

    Directory of Open Access Journals (Sweden)

    Xiang Zhao

    2013-07-01

    Full Text Available In this paper, a 3-phase induction motor model for simulation the field oriented control (FOC system based on space vector pulse width modulation (SVPWM is established in Ansoft/Simplorer software. The theory of field oriented control (FOC and the principle of space vector pulse width modulation (SVPWM were introduced. The simulation results are presented and analyzed. A Simulink simulation model of field oriented control system is presented as a comparison under the same conditions. The results indicated that the Simplorer model had quick response speed, small torque fluctuations and good performance both in steady and dynamic states. Furthermore, the Simplorer model can be coupled with the finite element model of the motor to achieve field-circuit coupling simulation of induction motor’s field oriented control system.    

  9. Distinct changes in cortical and spinal excitability following high-frequency repetitive TMS to the human motor cortex.

    Science.gov (United States)

    Quartarone, Angelo; Bagnato, Sergio; Rizzo, Vincenzo; Morgante, Francesca; Sant'angelo, Antonio; Battaglia, Fortunato; Messina, Corrado; Siebner, Hartwig Roman; Girlanda, Paolo

    2005-02-01

    It has been shown that high-frequency repetitive transcranial magnetic stimulation (rTMS) to the human primary motor hand area (M1-HAND) can induce a lasting increase in corticospinal excitability. Here we recorded motor evoked potentials (MEPs) from the right first dorsal interosseus muscle to investigate how sub-threshold high-frequency rTMS to the M1-HAND modulates cortical and spinal excitability. In a first experiment, we gave 1500 stimuli of 5 Hz rTMS. At an intensity of 90% of active motor threshold, rTMS produced no effect on MEP amplitude at rest. Increasing the intensity to 90% of resting motor threshold (RMT), rTMS produced an increase in MEP amplitude. This facilitatory effect gradually built up during the course of rTMS, reaching significance after the administration of 900 stimuli. In a second experiment, MEPs were elicited during tonic contraction using weak anodal electrical or magnetic test stimuli. 1500 (but not 600) conditioning stimuli at 90% of RMT induced a facilitation of MEPs in the contracting FDI muscle. In a third experiment, 600 conditioning stimuli were given at 90% of RMT to the M1-HAND. Using two well-established conditioning-test paradigms, we found a decrease in short-latency intracortical inhibition (SICI), and a facilitation of the first peak of facilitatory I-waves interaction (SICF). There was no correlation between the relative changes in SICI and SICF. These results demonstrate that subthreshold 5 Hz rTMS can induce lasting changes in specific neuronal subpopulations in the human corticospinal motor system, depending on the intensity and duration of rTMS. Short 5 Hz rTMS (600 stimuli) at 90% of RMT can selectively shape the excitability of distinct intracortical circuits, whereas prolonged 5 Hz rTMS (> or =900 stimuli) provokes an overall increase in excitability of the corticospinal output system, including spinal motoneurones.

  10. Enhanced Corticospinal Excitability and Volitional Drive in Response to Shortening and Lengthening Strength Training and Changes Following Detraining

    Science.gov (United States)

    Tallent, Jamie; Goodall, Stuart; Gibbon, Karl C.; Hortobágyi, Tibor; Howatson, Glyn

    2017-01-01

    There is a limited understanding of the neurological adaptations responsible for changes in strength following shortening and lengthening resistance training and subsequent detraining. The aim of the study was to investigate differences in corticospinal and spinal responses to resistance training of the tibialis anterior muscle between shortening or lengthening muscle contractions for 4 weeks and after 2 weeks of detraining. Thirty-one untrained individuals were assigned to either shortening or lengthening isokinetic resistance training (4 weeks, 3 days/weeks) or a non-training control group. Transcranial magnetic stimulation and peripheral nerve stimulation (PNS) were used to assess corticospinal and spinal changes, respectively, at pre-, mid-, post-resistance training and post detraining. Greater increases changes (P MVC were found from the respective muscle contraction training. Motor evoked potentials (expressed relative to background EMG) significantly increased in lengthening resistance training group under contraction intensities ranging from 25 to 80% of the shortening and lengthening contraction intensity (P MVC and V-wave did not change (P > 0.05), although MEP amplitude decreased during the detraining period (P < 0.01). No changes in H-reflex were found pre to post resistance training or post detraining. Modulation in V-wave appeared to be contraction specific, whereby greatest increases occurred following lengthening resistance training. Strength and volitional drive is maintained following 2 weeks detraining, however corticospinal excitability appears to decrease when the training stimulus is withdrawn. PMID:28223941

  11. Repeatability of corticospinal and spinal measures during lengthening and shortening contractions in the human tibialis anterior muscle.

    Directory of Open Access Journals (Sweden)

    Jamie Tallent

    Full Text Available UNLABELLED: Elements of the human central nervous system (CNS constantly oscillate. In addition, there are also methodological factors and changes in muscle mechanics during dynamic muscle contractions that threaten the stability and consistency of transcranial magnetic stimulation (TMS and perpherial nerve stimulation (PNS measures. PURPOSE: To determine the repeatability of TMS and PNS measures during lengthening and shortening muscle actions in the intact human tibialis anterior. METHODS: On three consecutive days, 20 males performed lengthening and shortening muscle actions at 15, 25, 50 and 80% of maximal voluntary contraction (MVC. The amplitude of the Motor Evoked Potentials (MEPs produced by TMS was measured at rest and during muscle contraction at 90° of ankle joint position. MEPs were normalised to Mmax determined with PNS. The corticospinal silent period was recorded at 80% MVC. Hoffman reflex (H-reflex at 10% isometric and 25% shortening and lengthening MVCs, and V-waves during MVCs were also evoked on each of the three days. RESULTS: With the exception of MEPs evoked at 80% shortening MVC, all TMS-derived measures showed good reliability (ICC = 0.81-0.94 from days 2 to 3. Confidence intervals (CI, 95% were lower between days 2 and 3 when compared to days 1 and 2. MEPs significantly increased at rest from days 1 to 2 (P = 0.016 and days 1 to 3 (P = 0.046. The H-reflex during dynamic muscle contraction was reliable across the three days (ICC = 0.76-0.84. V-waves (shortening, ICC = 0.77, lengthening ICC = 0.54 and the H-reflex at 10% isometric MVC (ICC = 0.66 was generally less reliable over the three days. CONCLUSION: Although it is well known that measures of the intact human CNS exhibit moment-to-moment fluctuations, careful experimental arrangements make it possible to obtain consistent and repeatable measurements of corticospinal and spinal excitability in the actively lengthening and shortening human

  12. The strength of the corticospinal coherence depends on the predictability of modulated isometric forces.

    Science.gov (United States)

    Mendez-Balbuena, Ignacio; Naranjo, Jose Raul; Wang, Xi; Andrykiewicz, Agnieska; Huethe, Frank; Schulte-Mönting, Jürgen; Hepp-Reymond, Marie-Claude; Kristeva, Rumyana

    2013-03-01

    Isometric compensation of predictably frequency-modulated low forces is associated with corticomuscular coherence (CMC) in beta and low gamma range. It remains unclear how the CMC is influenced by unpredictably modulated forces, which create a mismatch between expected and actual sensory feedback. We recorded electroencephalography from the contralateral hand motor area, electromyography (EMG), and the motor performance of 16 subjects during a visuomotor task in which they had to isometrically compensate target forces at 8% of the maximum voluntary contraction with their right index finger. The modulated forces were presented with predictable or unpredictable frequencies. We calculated the CMC, the cortical motor alpha-, beta-, and gamma-range spectral powers (SP), and the task-related desynchronization (TRD), as well as the EMG SP and the performance. We found that in the unpredictable condition the CMC was significantly lower and associated with lower cortical motor SP, stronger TRD, higher EMG SP, and worse performance. The findings suggest that due to the mismatch between predicted and actual sensory feedback leading to higher computational load and less stationary motor state, the unpredictable modulation of the force leads to a decrease in corticospinal synchrony, an increase in cortical and muscle activation, and a worse performance.

  13. The nature of corticospinal paths driving human motoneurones during voluntary contractions.

    Science.gov (United States)

    Butler, Jane E; Larsen, Thomas S; Gandevia, Simon C; Petersen, Nicolas T

    2007-10-15

    The properties of the human motor cortex can be studied non-invasively using transcranial magnetic stimulation (TMS). Stimulation at high intensity excites corticospinal cells with fast conducting axons that make direct connections to motoneurones of human upper limb muscles, while low-intensity stimulation can suppress ongoing EMG. To assess whether these cells are used in normal voluntary contractions, we used TMS at very low intensities to suppress the firing of single motor units in biceps brachii (n = 14) and first dorsal interosseous (FDI, n = 6). Their discharge was recorded with intramuscular electrodes and cortical stimulation was delivered at multiple intensities at appropriate times during sustained voluntary firing at approximately 10 Hz. For biceps, high-intensity stimulation produced facilitation at 17.1 +/- 2.1 ms (lasting 2.4 +/- 0.9 ms), while low-intensity stimulation (below motor threshold) produced suppression (without facilitation) at 20.2 +/- 2.1 ms (lasting 7.6 +/- 2.2 ms). For FDI, high-intensity stimulation produced facilitation at 23.3 +/- 1.2 ms (lasting 1.8 +/- 0.4 ms), with suppression produced by low-intensity stimulation at 25.2 +/- 2.6 ms (lasting 7.5 +/- 2.6 ms). The difference between the onsets of facilitation and suppression was short: 3.1 +/- 1.2 ms for biceps and 2.0 +/- 1.5 ms for FDI. This latency difference is much less than that previously reported using surface EMG recordings ( approximately 10 ms). These data suggest that low-intensity cortical stimulation inhibits ongoing activity in fast-conducting corticospinal axons through an oligosynaptic (possibly disynaptic) path, and that this activity is normally contributing to drive the motoneurones during voluntary contractions.

  14. Selective stimulation of dendrite outgrowth from identified corticospinal neurons by homotopic astrocytes

    NARCIS (Netherlands)

    Gispen, W.H.; Dijkstra, S.; Bar, P.R.; Joosten, E.A.

    1999-01-01

    Corticospinal neurons were identified in primary cultures of cortical neurons established from rats that had been injected with a fluorescent tracer to retrogradely label the corticospinal tract. We measured neurite outgrowth from corticospinal neurons after they had been co-cultured with astrocytes

  15. Intensity dependent effects of transcranial direct current stimulation on corticospinal excitability in chronic spinal cord injury.

    Science.gov (United States)

    Murray, Lynda M; Edwards, Dylan J; Ruffini, Giulio; Labar, Douglas; Stampas, Argyrios; Pascual-Leone, Alvaro; Cortes, Mar

    2015-04-01

    To investigate the effects of anodal transcranial direct current stimulation (a-tDCS) intensity on corticospinal excitability and affected muscle activation in individuals with chronic spinal cord injury (SCI). Single-blind, randomized, sham-controlled, crossover study. Medical research institute and rehabilitation hospital. Volunteers (N = 9) with chronic SCI and motor dysfunction in wrist extensor muscles. Three single session exposures to 20 minutes of a-tDCS (anode over the extensor carpi radialis [ECR] muscle representation on the left primary motor cortex, cathode over the right supraorbital area) using 1 mA, 2 mA, or sham stimulation, delivered at rest, with at least 1 week between sessions. Corticospinal excitability was assessed with motor-evoked potentials (MEPs) from the ECR muscle using surface electromyography after transcranial magnetic stimulation. Changes in spinal excitability, sensory threshold, and muscle strength were also investigated. Mean MEP amplitude significantly increased by approximately 40% immediately after 2mA a-tDCS (pre: 0.36 ± 0.1 mV; post: 0.47 ± 0.11 mV; P = .001), but not with 1 mA or sham. Maximal voluntary contraction measures remained unaltered across all conditions. Sensory threshold significantly decreased over time after 1mA (P = .002) and 2mA (P = .039) a-tDCS and did not change with sham. F-wave persistence showed a nonsignificant trend for increase (pre: 32% ± 12%; post: 41% ± 10%; follow-up: 46% ± 12%) after 2 mA stimulation. No adverse effects were reported with any of the experimental conditions. The a-tDCS can transiently raise corticospinal excitability to affected muscles in patients with chronic SCI after 2 mA stimulation. Sensory perception can improve with both 1 and 2 mA stimulation. This study gives support to the safe and effective use of a-tDCS using small electrodes in patients with SCI and highlights the importance of stimulation intensity. Copyright © 2015 American Congress of Rehabilitation

  16. Novel sucker rod pumping system based on linear motor technology

    Institute of Scientific and Technical Information of China (English)

    李立毅; 李立清; 吴红星; 胡余生; 邹积岩

    2004-01-01

    Obtaining petroleum at the cost of electrical energy is a common problem in almost all oil fields, and it is mainly caused by low duty radio of induction motor used in beam pumping units. Traditional beam-pumping units have many intrinsic disadvantages such as low efficiency, complex transmission devices, poor flexibility,tremendous volume and weight in long stroke, etc. Therefore, a novel direct driven linear electromagnetic pumping unit (EMPU) has been developed by combining oil extraction technology with linear motor technology. The thrust of EMPU matches the changing of suspension center load to improve the system efficiency and cut down the consumption of energy. Based on previous experience, a small-scale prototype was developed and a simulation was conducted with it. Both theoretical analyses and experimental study showed that the problems exiting in beam pumping units can be solved with EMPU system, and this is a new method which can be used to solve high energy waste in oil fields.

  17. Low speed phaselock speed control system. [for brushless dc motor

    Science.gov (United States)

    Fulcher, R. W.; Sudey, J. (Inventor)

    1975-01-01

    A motor speed control system for an electronically commutated brushless dc motor is provided which includes a phaselock loop with bidirectional torque control for locking the frequency output of a high density encoder, responsive to actual speed conditions, to a reference frequency signal, corresponding to the desired speed. The system includes a phase comparator, which produces an output in accordance with the difference in phase between the reference and encoder frequency signals, and an integrator-digital-to-analog converter unit, which converts the comparator output into an analog error signal voltage. Compensation circuitry, including a biasing means, is provided to convert the analog error signal voltage to a bidirectional error signal voltage which is utilized by an absolute value amplifier, rotational decoder, power amplifier-commutators, and an arrangement of commutation circuitry.

  18. 78 FR 72146 - Motor Carrier Management Information System (MCMIS) Changes to Improve Uniformity in the...

    Science.gov (United States)

    2013-12-02

    ... Federal Motor Carrier Safety Administration Motor Carrier Management Information System (MCMIS) Changes to... Motor Carrier Management Information System (MCMIS) to allow the Agency to upload the results of... enforcement agency into FMCSA's information systems and the subsequent adjudication happens much later with...

  19. Stokes Efficiency of Molecular Motor-Cargo Systems

    Science.gov (United States)

    2008-01-01

    2655, 1994. 11 F. Reif , Fundamentals of Statistical and Thermal Physics, McGraw-Hill, New York, NY, USA, 1985. 12 H. Kleinert, Path Integrals in...Quantum Mechanics , Statistics , Polymer Physics, and Financial Markets, World Scientific, River Edge, NJ, USA, 3rd edition, 2004. 13 A. Einstein...Efficiency of Molecular Motor-Cargo Systems Hongyun Wang1 and Hong Zhou2 1Department of Applied Mathematics and Statistics , University of California

  20. Research on Direct Torque Control System Based on Induction Motor

    Institute of Scientific and Technical Information of China (English)

    康劲松; 陶生桂; 毛明平

    2003-01-01

    The mathematic model of direct torque control (DTC) was deduced. Two simulating models based on the MATLAB & SIMULINK were established. The emphasis is focused on study of the performance difference of the DTC system with stator flux hexagon and circle trajectories. The simulation waveforms of flux, torque and current characters with two flux trajectories were given. Experiments were carried out in an AC drive system based on induction motor and two-level inverter. A dual-CPU structure was used and the communication with two CPUs was obtained by a dual-port RAM in this system.

  1. Permanent Magnetic Synchronous Motor Control System Based on ADRC

    Directory of Open Access Journals (Sweden)

    Song Wang

    2013-06-01

    Full Text Available Permanent magnetic synchronous motor (PMSM is a strong coupling and non-linear system. In the PMSM speed-regulation system, PID controller is the conventional one, it is difficult to decide the parameters of PID. Moreover, the performance of PID controller is not very well in large disturbance. In the paper, the Active Disturbance Rejection Controller (ADRC is applied to the PMSM speed-regulation system. The result of simulations and experiments show that this algorithm has better anti-load-disturbance performance than PID controller.

  2. Is Remodelling of Corticospinal Tract Terminations Originating in the Intact Hemisphere Associated with Recovery following Transient Ischaemic Stroke in the Rat?

    Directory of Open Access Journals (Sweden)

    Emma J Mitchell

    Full Text Available Following large strokes that encompass the cerebral cortex, it has been suggested that the corticospinal tract originating from the non-ischaemic hemisphere reorganises its pattern of terminal arborisation within the spinal cord to compensate for loss of function. However many strokes in humans predominantly affect subcortical structures with minimal involvement of the cerebral cortex. The aim of the present study was to determine whether remodelling of corticospinal terminals arising from the non-ischaemic hemisphere was associated with spontaneous recovery in rats with subcortical infarcts. Rats were subjected to transient middle cerebral artery occlusion or sham surgery and 28 days later, when animals exhibited functional recovery, cholera toxin b subunit was injected into the contralesional, intact forelimb motor cortex in order to anterogradely label terminals within cervical spinal cord segments. Infarcts were limited to subcortical structures and resulted in partial loss of corticospinal tract axons from the ischaemic hemisphere. Quantitative analysis revealed there was no significant difference in the numbers of terminals on the contralesional side of the spinal grey matter between ischaemic and sham rats. The results indicate that significant remodelling of the corticospinal tract from the non-ischaemic hemisphere is not associated with functional recovery in animals with subcortical infarcts.

  3. Induction generator-induction motor wind-powered pumping system

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, M.S.; Lyra, R.O.C.; Silva, S.R. [CPDEE - UFMG, Belo Horizonte (Brazil)

    1997-12-31

    The energy storage matter plays an important role in wind-electric conversion systems for isolated applications. Having that in mind, two different approaches can be basically considered: either the immediate conversion of the generated electric energy, as in a water pumping system or electric energy storage for later use, as in a battery charging system. Due to some features such as no need of an external reactive power source and, sometimes, a gearbox, permanent-magnet synchronous generators have been broadly used in low rated power isolated systems. Despite that, system performance can be affected when the generator is feeding an inductive load (e.g., an induction motor) under variable-speed-variable-frequency operational conditions. Since there is no effective flux control, motor overload may occur at high wind speeds. Thus, good system performance can be obtained through additional control devices which may increase system cost. Although being rugged and cheap, induction machines always work as a reactive power drain; therefore, they demand an external reactive power source. Considering that, reactive static compensators appear as an attractive alternative to the cost x performance problem. In addition to that, different control strategies can be used so that system performance can be improved.

  4. An Insight into the Time Domain Phenomenon during the Transition Zone from Induction Motor to Synchronous Motor Mode for a Current Source Inverter Fed Synchronous Motor Drive System

    Directory of Open Access Journals (Sweden)

    A.B. Chattopadhyay

    2014-10-01

    Full Text Available Modeling of synchronous motor plays a dominant role in designing complicated drive system for different applications, especially large blower fans etc., for steel industries. As synchronous motor has no inherent starting torque generally it is started as an induction motor with the help of a damper winding and it pulls into synchronism under certain conditions. The present study exactly concentrates on this particular zone of transition from induction motor to synchronous motor mode for a current source inverter fed synchronous motor drive system. Due to complexity of synchronous motor in terms of number of windings and finite amount of air gap saliency, direct modeling of such transition zone in time domain becomes cumbersome at the first instance of modeling. That is why firstly the modeling is presented in complex frequency domain and then the time domain modeling is obtained by applying inverse Laplace transform technique. Apparently it seems to be a straight forward mathematical treatment but involvement of Convolution Integral for converting the formulation from s-domain to time domain becomes a matter of interest and it may draw the attention of various researchers working in this area. Furthermore the time domain response of the disturbance function may help a designer to fix up the time instant when the pull in phenomenon will be imposed by throwing the field winding to a DC supply.

  5. Synchronization of motor controller and PC system clocks

    Science.gov (United States)

    Kittmann, Frank; Bertram, Thomas; Briegel, Florian; Mohr, Lars; Berwein, Jürgen

    2010-07-01

    The power of the Large Binocular Telescope (LBT) with its two 8.4m primary mirrors sharing a common mount will unfold its full potential with the LINC-NIRVANA (LN) instrument. LINC-NIRVANA is a German-Italian beam combiner for the LBT and will interfere the light from the two 8.4m mirrors of the LBT in Fizeau mode. More than 140 motors have to be handled by custom developed Motor Controllers (MoCons). One important feature of the MoCon is the support of externally computed trajectories. Motion profiles provide information on the movement of the motor along a defined path over a certain period of time. Such profiles can be uploaded to the MoCon over Ethernet and can be started at a specific time. For field derotation it is critical that the derotation trajectories are executed with a very precise relative and absolute timing. This raises the problem of the synchronization of the MoCon internal clock with the system time of the servers that are hosting LINCNIRVANA's Instrument Control Software. The MoCon time should be known by the servers with an uncertainty of few milliseconds in order to match the start time of the motion profile and the field rotation trajectory. In this paper we will discuss how to synchronize the MoCon internal time and the PC system time.

  6. Development of a linear induction motor based artificial muscle system.

    Science.gov (United States)

    Gruber, A; Arguello, E; Silva, R

    2013-01-01

    We present the design of a linear induction motor based on electromagnetic interactions. The engine is capable of producing a linear movement from electricity. The design consists of stators arranged in parallel, which produce a magnetic field sufficient to displace a plunger along its axial axis. Furthermore, the winding has a shell and cap of ferromagnetic material that amplifies the magnetic field. This produces a force along the length of the motor that is similar to that of skeletal muscle. In principle, the objective is to use the engine in the development of an artificial muscle system for prosthetic applications, but it could have multiple applications, not only in the medical field, but in other industries.

  7. [Correlation between corticospinal tract degeneration through magnetic resonance imaging, and functional scale (ALSFRS) in patients with amyotrophic lateral sclerosis].

    Science.gov (United States)

    Garcia, Larissa Nery; Silva, Alexandre Vallota da; Carrete, Henrique; Favero, Francis Meire; Fontes, Sissy Veloso; Moneiro, Marcelo Tavares; Oliveira, Acary Souza Bulle de

    2007-09-01

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects the corticospinal tract. ALS functional rating scale (ALSFRS) is a questionnaire that quantifies motor deficits, while diffusion tensor imaging (DTI) evaluates the integrity of fibers through the fractional anisotropy (FA). In the present study, seven ALS patients were evaluated by ALSFRS and immediately submitted to DTI, getting FA values in the following regions: cerebral peduncle (PC), internal capsule (CI) and the white matter under the primary motor cortex (M1), secondary motor cortex (M2) and somesthetic cortex (SI). A control group was constituted by twelve healthy individuals. FA values in patients were significantly lower when compared with controls, with a tendency to higher reductions in the right hemisphere and more inferior regions. Interestingly, FA values were reduced in somesthetic area. No correlation was observed between symptoms duration and FA values. Despite the correlation observed between ALSFRS scores and degeneration in PC and CI, our results suggest that this subjective scale is not a good parameter for the evaluation of the structural damage in encephalic portions of the corticospinal tract.

  8. 75 FR 15620 - Federal Motor Vehicle Safety Standards; Air Brake Systems

    Science.gov (United States)

    2010-03-30

    ... National Highway Traffic Safety Administration 49 CFR Part 571 RIN 2127-AK62 Federal Motor Vehicle Safety... that amended the Federal motor vehicle safety standard for air brake systems by requiring substantial... 37122) amending Federal Motor Vehicle Safety Standard (FMVSS) No. 121, Air Brake Systems, to...

  9. 76 FR 44829 - Federal Motor Vehicle Safety Standards; Air Brake Systems

    Science.gov (United States)

    2011-07-27

    ... Administration 49 CFR Part 571 [Docket No. NHTSA-2009-0175] RIN 2127-AK84 Federal Motor Vehicle Safety Standards... published a final rule that amended the Federal motor vehicle safety standard for air brake systems by... Federal Motor Vehicle Safety Standard (FMVSS) No. 121, Air Brake Systems, to require improved...

  10. 77 FR 30765 - Federal Motor Vehicle Safety Standards; Electronic Stability Control Systems for Heavy Vehicles

    Science.gov (United States)

    2012-05-23

    ... CFR Part 571 Federal Motor Vehicle Safety Standards; Electronic Stability Control Systems for Heavy... 571 RIN 2127-AK97 Federal Motor Vehicle Safety Standards; Electronic Stability Control Systems for... a new Federal Motor Vehicle Safety Standard No. 136 to require electronic stability control (ESC...

  11. Characters of MR diffusion tensor imaging in cerebral ischemic corticospinal tract injury

    Institute of Scientific and Technical Information of China (English)

    Ziqian Chen; Ping Ni; Hui Xiao; Youqiang Ye; Gennian Qian; Shangwen Xu; Xizhang Yang; Jinhua Chen; Biyun Zhang

    2006-01-01

    BACKGROUND: Diffusion tensor imaging (DTI) is one of the noninvasive methods to study the morphological structure of brain white matter fibrous bands in vivo, and it has been applied primarily in clinic. DTI is acknowledged as the more effective imaging method to diagnose ultra-acute and/or acute cerebral infarction.OBJECTIVE: To observe the anisotropic characters of cerebral white matter fibrous bands in patients with ischemic stroke by using DTI, and investigate the correlation between the damage of corticospinal tract and muscle strength in patients with ischemic stroke at acute period.DESIGN: A case-control observation.SETTING: Department of Medical Imaging, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA.PARTICIpANTS: Nine inpatients with injury of motor function induced by acute ischemic stroke (patient group) at 6 hours to 2 weeks after the attack were selected from the Department of Neurology, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from September 2005 to March 2006,and they all accorded with the present diagnostic standard for cerebrovascular disease in China. There were 5 males and 4 females, aged 16-87 years. At the same time, nine healthy right-handed physical examinees matched by age and sex with the patients were taken as the control group, and they all had no nervous disease, mental diseases, cerebrovascular abnormalities and injury history, etc. All the subjects were informed with the detected items and agreed to participate in the study.METHODS: All the 9 patients with ischemic stroke at acute period and 9 healthy subjects were examined with MRI, T1 weighted imaging, T2 weighted imaging and DTI. And the data were processed offline with dTV.Ⅱ software, the images of fractional anisotropy and directional encoded color (DEC) were obtained, and the three-dimensional fibrous band images of bilateral corticospinal tracts were reconstructed. In the control group, the values of fractional anisotropy

  12. Motor Control and Regulation for a Flywheel Energy Storage System

    Science.gov (United States)

    Kenny, Barbara; Lyons, Valerie

    2003-01-01

    This talk will focus on the motor control algorithms used to regulate the flywheel system at the NASA Glenn Research Center. First a discussion of the inner loop torque control technique will be given. It is based on the principle of field orientation and is implemented without a position or speed sensor (sensorless control). Then the outer loop charge and discharge algorithm will be presented. This algorithm controls the acceleration of the flywheel during charging and the deceleration while discharging. The algorithm also allows the flywheel system to regulate the DC bus voltage during the discharge cycle.

  13. New Heuristics for Interfacing Human Motor System using Brain Waves

    Directory of Open Access Journals (Sweden)

    Mohammed El-Dosuky

    2012-09-01

    Full Text Available There are many new forms of interfacing human users to machines. We persevere here electric-mechanical form of interaction between human and machine. The emergence of brain-computer interface allows mind-to-movement systems. The story of the Pied Piper inspired us to devise some new heuristics for interfacing human motor system using brain waves, by combining head helmet and LumbarMotionMonitor. For the simulation we use java GridGain. Brain responses of classified subjects during training indicates that Probe can be the best stimulus to rely on in distinguishing between knowledgeable and not knowledgeable

  14. Fully automated detection of corticospinal tract damage in chronic stroke patients.

    Science.gov (United States)

    Yang, Ming; Yang, Ya-ru; Li, Hui-jun; Lu, Xue-song; Shi, Yong-mei; Liu, Bin; Chen, Hua-jun; Teng, Gao-jun

    2014-01-01

    Structural integrity of the corticospinal tract (CST) after stroke is closely linked to the degree of motor impairment. However, current methods for measurement of fractional atrophy (FA) of CST based on region of interest (ROI) are time-consuming and open to bias. Here, we used tract-based spatial statistics (TBSS) together with a CST template with healthy volunteers to quantify structural integrity of CST automatically. Two groups of patients after ischemic stroke were enrolled, group 1 (10 patients, 7 men, and Fugl-Meyer assessment (FMA) scores ⩽ 50) and group 2 (12 patients, 12 men, and FMA scores = 100). CST of FA(ipsi), FA(contra), and FA(ratio) was compared between the two groups. Relative to group 2, FA was decreased in group 1 in the ipsilesional CST (P stroke, which would facilitate implementation of clinical practice.

  15. Structural and functional abnormalities of the motor system in developmental stuttering

    National Research Council Canada - National Science Library

    Watkins, Kate E; Smith, Stephen M; Davis, Steve; Howell, Peter

    Though stuttering is manifest in its motor characteristics, the cause of stuttering may not relate purely to impairments in the motor system as stuttering frequency is increased by linguistic factors...

  16. Dynamic equivalent method of interconnected power systems with consideration of motor loads

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The existing equivalent methods usually only deal with static load models and neglect the dynamic characteristics of loads such as induction motors.This paper presents a dynamic equivalent method which considers motor dynamics.At first,the clustering criterion of motor loads is given.The motors with similar dynamic characteristics are classified into one group.Then,reduction of motors in the same group is carried out.Finally,parameters of the equivalent motor are calculated and the equivalent system is thus obtained.This aggregation method is applied to the New England system of 39-buses and 10-generators.Simulation results show that the equivalent system retains the dynamic performance of the original system with good accuracy.Compared with the 1-motor equivalent scheme,the 2-motor equivalent scheme can improve equivalent precision effectively.

  17. The Effect of Visual and Auditory Enhancements on Excitability of the Primary Motor Cortex during Motor Imagery: A Pilot Study

    Science.gov (United States)

    Ikeda, Kohei; Higashi, Toshio; Sugawara, Kenichi; Tomori, Kounosuke; Kinoshita, Hiroshi; Kasai, Tatsuya

    2012-01-01

    The effect of visual and auditory enhancements of finger movement on corticospinal excitability during motor imagery (MI) was investigated using the transcranial magnetic stimulation technique. Motor-evoked potentials were elicited from the abductor digit minimi muscle during MI with auditory, visual and, auditory and visual information, and no…

  18. Preparation and execution of teeth clenching and foot muscle contraction influence on corticospinal hand-muscle excitability

    Science.gov (United States)

    Komeilipoor, Naeem; Ilmoniemi, Risto J.; Tiippana, Kaisa; Vainio, Martti; Tiainen, Mikko; Vainio, Lari

    2017-01-01

    Contraction of a muscle modulates not only the corticospinal excitability (CSE) of the contracting muscle but also that of different muscles. We investigated to what extent the CSE of a hand muscle is modulated during preparation and execution of teeth clenching and ipsilateral foot dorsiflexion either separately or in combination. Hand-muscle CSE was estimated based on motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) and recorded from the first dorsal interosseous (FDI) muscle. We found higher excitability during both preparation and execution of all the motor tasks than during mere observation of a fixation cross. As expected, the excitability was greater during the execution phase than the preparation one. Furthermore, both execution and preparation of combined motor tasks led to higher excitability than individual tasks. These results extend our current understanding of the neural interactions underlying simultaneous contraction of muscles in different body parts. PMID:28117368

  19. PARAMETER ESTIMATION METHODOLOGY FOR NONLINEAR SYSTEMS: APPLICATION TO INDUCTION MOTOR

    Institute of Scientific and Technical Information of China (English)

    G.KENNE; F.FLORET; H.NKWAWO; F.LAMNABHI-LAGARRIGUE

    2005-01-01

    This paper deals with on-line state and parameter estimation of a reasonably large class of nonlinear continuous-time systems using a step-by-step sliding mode observer approach. The method proposed can also be used for adaptation to parameters that vary with time. The other interesting feature of the method is that it is easily implementable in real-time. The efficiency of this technique is demonstrated via the on-line estimation of the electrical parameters and rotor flux of an induction motor. This application is based on the standard model of the induction motor expressed in rotor coordinates with the stator current and voltage as well as the rotor speed assumed to be measurable.Real-time implementation results are then reported and the ability of the algorithm to rapidly estimate the motor parameters is demonstrated. These results show the robustness of this approach with respect to measurement noise, discretization effects, parameter uncertainties and modeling inaccuracies.Comparisons between the results obtained and those of the classical recursive least square algorithm are also presented. The real-time implementation results show that the proposed algorithm gives better performance than the recursive least square method in terms of the convergence rate and the robustness with respect to measurement noise.

  20. Assessing Energy Efficiency Opportunities in US Industrial and Commercial Building Motor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Prakash; Sheaffer, Paul; McKane, Aimee; Scheihing, Paul

    2015-09-01

    In 2002, the United States Department of Energy (USDOE) published an energy efficiency assessment of U.S. industrial sector motor systems titled United States Industrial Electric Motor Systems Market Opportunities Assessment. The assessment advanced motor system efficiency by providing a greater understanding of the energy consumption, use characteristics, and energy efficiency improvement potential of industrial sector motor systems in the U.S. Since 2002, regulations such as Minimum Energy Performance Standards, cost reductions for motor system components such as variable frequency drives, system-integrated motor-driven equipment, and awareness programs for motor system energy efficiency have changed the landscape of U.S. motor system energy consumption. To capture the new landscape, the USDOE has initiated a three-year Motor System Market Assessment (MSMA), led by Lawrence Berkeley National Laboratory (LBNL). The MSMA will assess the energy consumption, operational and maintenance characteristics, and efficiency improvement opportunity of U.S. industrial sector and commercial building motor systems. As part of the MSMA, a significant effort is currently underway to conduct field assessments of motor systems from a sample of facilities representative of U.S. commercial and industrial motor system energy consumption. The Field Assessment Plan used for these assessments builds on recent LBNL research presented at EEMODS 2011 and EEMODS 2013 using methods for characterizing and determining regional motor system energy efficiency opportunities. This paper provides an update on the development and progress of the MSMA, focusing on the Field Assessment Plan and the framework for assessing the global supply chain for emerging motors and drive technologies.

  1. Modeling and Simulation Multi Motors Web Winding System

    Directory of Open Access Journals (Sweden)

    Hachemi Glaoui

    2013-03-01

    Full Text Available Web winding systems allow the operations of unwinding and rewinding of various products including plastic films, sheets of paper, sheets, and fabrics. These operations are necessary for the development and the treatment of these products. Web winding systems generally consist of the same machine elements in spite of the diversity of the transported products. Due to the wide rang variation of the radius and inertia of the rollers the system dynamic change considerably during the winding/ unwinding process. Decentralized PI controller for web tension control and linear speed control are presented in this paper. The PI control method can be applied easily and is widely known, it has an important place in control applications. Simulation results show the effectiveness of the proposed linear speed and tension controller for web winding multi motors systems.

  2. A Novel Single Phase Hybrid Switched Reluctance Motor Drive System

    DEFF Research Database (Denmark)

    Liang, Jianing; Xu, Guoqing; Jian, Linni;

    2011-01-01

    phase boost converter is applied to improve the performance of this motor. It is easy to generate a double dclink voltage and dc-link voltage and switch both of them. The voltage of boost capacitor is self balance, so the protective circuit is not need to consider. The fast excitation mode helps hybrid...... SRM reduce the negative torque before zero-crossing point of torque curve, and build desired phase current to generate more power. Some experimental results are done to verify the performance of proposed hybrid SRM drive system....

  3. 78 FR 9623 - Federal Motor Vehicle Safety Standards; Air Brake Systems

    Science.gov (United States)

    2013-02-11

    ... National Highway Traffic Safety Administration 49 CFR Part 571 RIN 2127-AL11 Federal Motor Vehicle Safety... published a final rule that amended the Federal motor vehicle safety standard for air brake systems by... published a final rule in the Federal Register amending Federal Motor Vehicle Safety Standard (FMVSS)...

  4. Fine motor skills in adult Tourette patients are task-dependent

    Directory of Open Access Journals (Sweden)

    Neuner Irene

    2012-10-01

    Full Text Available Abstract Background Tourette syndrome is a neuropsychiatric disorder characterized by motor and phonic tics. Deficient motor inhibition underlying tics is one of the main hypotheses in its pathophysiology. Therefore the question arises whether this supposed deficient motor inhibition affects also voluntary movements. Despite severe motor tics, different personalities who suffer from Tourette perform successfully as neurosurgeon, pilot or professional basketball player. Methods For the investigation of fine motor skills we conducted a motor performance test battery in an adult Tourette sample and an age matched group of healthy controls. Results The Tourette patients showed a significant lower performance in the categories steadiness of both hands and aiming of the right hand in comparison to the healthy controls. A comparison of patients’ subgroup without comorbidities or medication and healthy controls revealed a significant difference in the category steadiness of the right hand. Conclusions Our results show that steadiness and visuomotor integration of fine motor skills are altered in our adult sample but not precision and speed of movements. This alteration pattern might be the clinical vignette of complex adaptations in the excitability of the motor system on the basis of altered cortical and subcortical components. The structurally and functionally altered neuronal components could encompass orbitofrontal, ventrolateral prefrontal and parietal cortices, the anterior cingulate, amygdala, primary motor and sensorimotor areas including altered corticospinal projections, the corpus callosum and the basal ganglia.

  5. Design of a Solar Motor Drive System Fed by a Direct-Connected Photovoltaic Array

    Directory of Open Access Journals (Sweden)

    AYDOGMUS, O.

    2012-08-01

    Full Text Available A solar motor pump drive system is modeled and simulated. The proposed drive system does not require any kind of energy storage system and dc-dc converter. The system is connected directly to a photovoltaic (PV array. Thus, a low cost solar system can be achieved. A vector controlled Permanent Magnet Synchronous Motor (PMSM is used as a solar motor to increase the efficiency of system. The motor is designed for a low rated voltage level about 24V. The hill climbing MPPT method is used for balanced the motor power and PV power to obtain a high efficiency. The results are performed by using MATLAB/SimPowerSystem blocks. In addition, the PV array is modeled to allow for the possibility of running as on-line adjustable in simulation environment without using lookup table. The performances of motor, MPPT and drive system are analyzed in different conditions as temperature and irradiation of PV array.

  6. Intraoperative diffusion tensor imaging predicts the recovery of motor dysfunction after insular lesions

    Institute of Scientific and Technical Information of China (English)

    Jinjiang Li; Xiaolei Chen; Jiashu Zhang; Gang Zheng; Xueming Lv; Fangye Li; Shen Hu; Ting Zhang; Bainan Xu

    2013-01-01

    Insular lesions remain surgically challenging because of the need to balance aggressive resection and functional protection. Motor function deficits due to corticospinal tract injury are a common complication of surgery for lesions adjacent to the internal capsule and it is therefore essential to evaluate the corticospinal tract adjacent to the lesion. We used diffusion tensor imaging to evaluate the corticospinal tract in 89 patients with insular lobe lesions who underwent surgery in Chinese PLA General Hospital from February 2009 to May 2011. Postoperative motor function evaluation revealed that 57 patients had no changes in motor function, and 32 patients suffered motor dysfunction or aggravated motor dysfunction. Of the affected patients, 20 recovered motor function during the 6–12-month follow-up, and an additional 12 patients did not recover over more than 12 months of follow-up. Following reconstruction of the corticospinal tract, fractional anisotropy comparison demonstrated that preoperative, intraoperative and follow-up normalized fractional anisotropy in the stable group was higher than in the transient deficits group or the long-term deficits group. Compared with the transient deficits group, intraoperative normalized fractional anisotropy significantly decreased in the long-term deficits group. We conclude that intraoperative fractional anisotropy values of the corticospinal tracts can be used as a prognostic indicator of motor function outcome.

  7. A novel cortical target to enhance hand motor output in humans with spinal cord injury.

    Science.gov (United States)

    Long, Jinyi; Federico, Paolo; Perez, Monica A

    2017-06-01

    A main goal of rehabilitation strategies in humans with spinal cord injury is to strengthen transmission in spared neural networks. Although neuromodulatory strategies have targeted different sites within the central nervous system to restore motor function following spinal cord injury, the role of cortical targets remain poorly understood. Here, we use 180 pairs of transcranial magnetic stimulation for ∼30 min over the hand representation of the motor cortex at an interstimulus interval mimicking the rhythmicity of descending late indirect (I) waves in corticospinal neurons (4.3 ms; I-wave protocol) or at an interstimulus interval in-between I-waves (3.5 ms; control protocol) on separate days in a randomized order. Late I-waves are thought to arise from trans-synaptic cortical inputs and have a crucial role in the recruitment of spinal motor neurons following spinal cord injury. Motor evoked potentials elicited by transcranial magnetic stimulation, paired-pulse intracortical inhibition, spinal motor neuron excitability (F-waves), index finger abduction force and electromyographic activity as well as a hand dexterity task were measured before and after both protocols in 15 individuals with chronic incomplete cervical spinal cord injury and 17 uninjured participants. We found that motor evoked potentials size increased in spinal cord injury and uninjured participants after the I-wave but not the control protocol for ∼30 to 60 min after the stimulation. Intracortical inhibition decreased and F-wave amplitude and persistence increased after the I-wave but not the control protocol, suggesting that cortical and subcortical networks contributed to changes in corticospinal excitability. Importantly, hand motor output and hand dexterity increased in individuals with spinal cord injury after the I-wave protocol. These results provide the first evidence that late synaptic input to corticospinal neurons may represent a novel therapeutic target for improving motor function

  8. Motor response complications and the function of striatal efferent systems.

    Science.gov (United States)

    Chase, T N; Mouradian, M M; Engber, T M

    1993-12-01

    Motor response complications eventually appear in most patients with advanced Parkinson's disease being treated with levodopa. The interval between onset of parkinsonism and emergence of these adverse events appears independent of the dose or the duration of therapy. Current evidence suggests that "wearing-off" fluctuations largely reflect the loss of normally functioning dopaminergic terminals, although postsynaptic alterations contribute somewhat to the underlying decline in the duration of levodopa's antiparkinsonian action. "On-off" fluctuations and peak-dose dyskinesias, on the other hand, appear to arise mainly as a consequence of postjunctional alterations that follow exposure to nonphysiologic intrasynaptic dopamine fluctuations in patients who have lost the buffering afforded by dopaminergic terminals. Studies in rats with 6-hydroxydopamine lesions indicate that striking functional alterations occur in striatal dopaminoceptive systems as a result of dopaminergic denervation and that levodopa replacement, particularly when given intermittently, fails to normalize these changes. To the extent that similar alterations contribute to the appearance of motor complications, the successful symptomatic therapy of Parkinson's disease may require continuous dopaminergic stimulation, as well as direct pharmacologic targeting of striatal dopaminoceptive systems.

  9. Motor system contributions to verbal and non-verbal working memory

    Directory of Open Access Journals (Sweden)

    Diana A Liao

    2014-09-01

    Full Text Available Working memory (WM involves the ability to maintain and manipulate information held in mind. Neuroimaging studies have shown that secondary motor areas activate during WM for verbal content (e.g., words or letters, in the absence of primary motor area activation. This activation pattern may reflect an inner speech mechanism supporting online phonological rehearsal. Here, we examined the causal relationship between motor system activity and WM processing by using transcranial magnetic stimulation (TMS to manipulate motor system activity during WM rehearsal. We tested WM performance for verbalizable (words and pseudowords and non-verbalizable (Chinese characters visual information. We predicted that disruption of motor circuits would specifically affect WM processing of verbalizable information. We found that TMS targeting motor cortex slowed response times on verbal WM trials with high (pseudoword vs. low (real word phonological load. However, non-verbal WM trials were also significantly slowed with motor TMS. WM performance was unaffected by sham stimulation or TMS over visual cortex. Self-reported use of motor strategy predicted the degree of motor stimulation disruption on WM performance. These results provide evidence of the motor system’s contributions to verbal and non-verbal WM processing. We speculate that the motor system supports WM by creating motor traces consistent with the type of information being rehearsed during maintenance.

  10. Muscle relaxation of the foot reduces corticospinal excitability of hand muscles and enhances intracortical inhibition

    Directory of Open Access Journals (Sweden)

    Kouki eKato

    2016-05-01

    Full Text Available The object of this study was to clarify the effects of foot muscle relaxation on activity in the primary motor cortex of the hand area. Subjects were asked to volitionally relax the right foot from sustained contraction of either the dorsiflexor (tibialis anterior; TA relaxation or plantarflexor (soleus; SOL relaxation in response to an auditory stimulus. Single- and paired-pulse transcranial magnetic stimulation (TMS was delivered to the hand area of the left primary motor cortex at different time intervals before and after the onset of TA or SOL relaxation. Motor evoked potentials (MEPs were recorded from the right extensor carpi radialis (ECR and flexor carpi radialis (FCR. MEP amplitudes of ECR and FCR caused by single-pulse TMS temporarily decreased after TA and SOL relaxation onset, respectively, as compared with those of the resting control. Furthermore, short-interval intracortical inhibition (SICI of ECR evaluated with paired-pulse TMS temporarily increased after TA relaxation onset. Our findings indicate that muscle relaxation of the dorsiflexor reduced corticospinal excitability of the ipsilateral hand muscles. This is most likely caused by an increase in intracortical inhibition.

  11. Study on Downsizing Techniques for Conventional Motor with Solid Insulation System

    Science.gov (United States)

    Matsumoto, Hironori; Ohtake, Atsushi; Enomoto, Yuji

    Downsizing has become essential in the development of motors recently in order to meet requirements related to environmental issues such as resource depletion and energy shortages. To fulfill these demands, we propose downsizing techniques for a conventional motor where a solid insulation system is hired and a large amount of insulation resin was employed to replace structural metal materials used in conventional motors. This paper deals with a feasibility study of a solid insulation system applied downsized motor. The optimal heat design, mechanically stable structure, and proper insulation resin are proposed and discussed. A prototype motor was manufactured, and results of a basic insulation test, temperature rise test and noise test are presented.

  12. Phase- and Workload-Dependent Changes in Corticospinal Excitability to the Biceps and Triceps Brachii during Arm Cycling

    Directory of Open Access Journals (Sweden)

    Alyssa-Joy Spence

    2016-12-01

    Full Text Available This is the first study to examine corticospinal excitability (CSE to antagonistic muscle groups during arm cycling. Transcranial magnetic stimulation (TMS of the motor cortex and transmastoid electrical stimulation (TMES of the corticospinal tract were used to assess changes in supraspinal and spinal excitability, respectively. TMS induced motor evoked potentials (MEPs and TMES induced cervicomedullary evoked potentials (CMEPs were recorded from the biceps and triceps brachii at two positions, mid-elbow flexion and extension, while cycling at 5% and 15% of peak power output. While phase-dependent modulation of MEP and CMEP amplitudes occurred in the biceps brachii, there was no difference between flexion and extension for MEP amplitudes in the triceps brachii and CMEP amplitudes were higher during flexion than extension. Furthermore, MEP amplitudes in both biceps and triceps brachii increased with increased workload. CMEP amplitudes increased with higher workloads in the triceps brachii, but not biceps brachii, though the pattern of change in CMEPs was similar to MEPs. Differences between changes in CSE between the biceps and triceps brachii suggest that these antagonistic muscles may be under different neural control during arm cycling. Putative mechanisms are discussed.

  13. Transportation of drug-gold nanocomposites by actinomyosin motor system

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Harsimran, E-mail: microsimbac@gmail.com; Chaudhary, Archana; Kaur, Inderpreet [Council of Scientific and Industrial Research (CSIR), Biomolecular Electronics and Nanotechnology Division (BEND), Central Scientific Instruments Organization - CSIO (India); Singh, Kashmir [Panjab University, Department of Biotechnology (India); Bharadwaj, Lalit M. [Council of Scientific and Industrial Research (CSIR), Biomolecular Electronics and Nanotechnology Division (BEND), Central Scientific Instruments Organization - CSIO (India)

    2011-06-15

    Nanotechnology is playing an important role in drug delivery to overcome limitations of conventional drug delivery systems in terms of solubility, in vivo stability, pharmacokinetics, and bio-distribution. The controlled transportation of drug into the cell and within the cell is a major challenge to be addressed. Cellular molecular motors have been exploited for their cargo carrying capacity for various applications including engineering and health care. Combination of nanotechnology and biomolecular motors can address some of the challenges in drug delivery. In the present study, transportation of drug nanocomposites has been demonstrated. Nanocomposites of 6-mercaptopurine and levodopa drugs (cancer and Parkinson's disease, respectively) were prepared with gold nanoparticles (GNPs) by covalent attachment and these nanocomposites were attached to actin filaments. These nanocomposites were in-turn transported by actin filaments on myosin tracks. Characterization of drug nanocomposites formation was done by UV-Vis spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and confocal microscopy. GNP composites of 6-mercaptopurine and levodopa were formed by sulfide and amide bond formation, respectively. Average velocity of actin filament attached to nanocomposites was found to be 3.17 and 3.89 {mu}m/s for levodopa and 6-mercaptopurine, respectively, as compared to actin filaments with velocity of 4.0-6.0 {mu}m/s. Three concepts have been proposed for the study of drug transportation into the cell based on polycationic complex formation, interaction of actin with cellular myosin and Biomolecular Adaptor for Retrograde Transport (BART) technology. The aspects of this study heads toward the development of an approach to utilize molecular motors for nanoscale transportation endogenously.

  14. Limited Angle Torque Motors Having High Torque Density, Used in Accurate Drive Systems

    Directory of Open Access Journals (Sweden)

    R. Obreja

    2011-01-01

    Full Text Available A torque motor is a special electric motor that is able to develop the highest possible torque in a certain volume. A torque motor usually has a pancake configuration, and is directly jointed to a drive system (without a gear box. A limited angle torque motor is a torque motor that has no rotary electromagnetic field — in certain papers it is referred to as a linear electromagnet. The main intention of the authors for this paper is to present a means for analyzing and designing a limited angle torque motor only through the finite element method. Users nowadays require very high-performance limited angle torque motors with high density torque. It is therefore necessary to develop the highest possible torque in a relatively small volume. A way to design such motors is by using numerical methods based on the finite element method.

  15. Reflecting on mirror mechanisms: motor resonance effects during action observation only present with low-intensity transcranial magnetic stimulation.

    Directory of Open Access Journals (Sweden)

    Michela Loporto

    Full Text Available Transcranial magnetic stimulation (TMS studies indicate that the observation of other people's actions influences the excitability of the observer's motor system. Motor evoked potential (MEP amplitudes typically increase in muscles which would be active during the execution of the observed action. This 'motor resonance' effect is thought to result from activity in mirror neuron regions, which enhance the excitability of the primary motor cortex (M1 via cortico-cortical pathways. The importance of TMS intensity has not yet been recognised in this area of research. Low-intensity TMS predominately activates corticospinal neurons indirectly, whereas high-intensity TMS can directly activate corticospinal axons. This indicates that motor resonance effects should be more prominent when using low-intensity TMS. A related issue is that TMS is typically applied over a single optimal scalp position (OSP to simultaneously elicit MEPs from several muscles. Whether this confounds results, due to differences in the manner that TMS activates spatially separate cortical representations, has not yet been explored. In the current study, MEP amplitudes, resulting from single-pulse TMS applied over M1, were recorded from the first dorsal interosseous (FDI and abductor digiti minimi (ADM muscles during the observation of simple finger abductions. We tested if the TMS intensity (110% vs. 130% resting motor threshold or stimulating position (FDI-OSP vs. ADM-OSP influenced the magnitude of the motor resonance effects. Results showed that the MEP facilitation recorded in the FDI muscle during the observation of index-finger abductions was only detected using low-intensity TMS. In contrast, changes in the OSP had a negligible effect on the presence of motor resonance effects in either the FDI or ADM muscles. These findings support the hypothesis that MN activity enhances M1 excitability via cortico-cortical pathways and highlight a methodological framework by which the

  16. Reflecting on mirror mechanisms: motor resonance effects during action observation only present with low-intensity transcranial magnetic stimulation.

    Science.gov (United States)

    Loporto, Michela; Holmes, Paul S; Wright, David J; McAllister, Craig J

    2013-01-01

    Transcranial magnetic stimulation (TMS) studies indicate that the observation of other people's actions influences the excitability of the observer's motor system. Motor evoked potential (MEP) amplitudes typically increase in muscles which would be active during the execution of the observed action. This 'motor resonance' effect is thought to result from activity in mirror neuron regions, which enhance the excitability of the primary motor cortex (M1) via cortico-cortical pathways. The importance of TMS intensity has not yet been recognised in this area of research. Low-intensity TMS predominately activates corticospinal neurons indirectly, whereas high-intensity TMS can directly activate corticospinal axons. This indicates that motor resonance effects should be more prominent when using low-intensity TMS. A related issue is that TMS is typically applied over a single optimal scalp position (OSP) to simultaneously elicit MEPs from several muscles. Whether this confounds results, due to differences in the manner that TMS activates spatially separate cortical representations, has not yet been explored. In the current study, MEP amplitudes, resulting from single-pulse TMS applied over M1, were recorded from the first dorsal interosseous (FDI) and abductor digiti minimi (ADM) muscles during the observation of simple finger abductions. We tested if the TMS intensity (110% vs. 130% resting motor threshold) or stimulating position (FDI-OSP vs. ADM-OSP) influenced the magnitude of the motor resonance effects. Results showed that the MEP facilitation recorded in the FDI muscle during the observation of index-finger abductions was only detected using low-intensity TMS. In contrast, changes in the OSP had a negligible effect on the presence of motor resonance effects in either the FDI or ADM muscles. These findings support the hypothesis that MN activity enhances M1 excitability via cortico-cortical pathways and highlight a methodological framework by which the neural

  17. Cerebellum tunes the excitability of the motor system: evidence from peripheral motor axons.

    Science.gov (United States)

    Nodera, Hiroyuki; Manto, Mario

    2014-12-01

    Cerebellum is highly connected with the contralateral cerebral cortex. So far, the motor deficits observed in acute focal cerebellar lesions in human have been mainly explained on the basis of a disruption of the cerebello-thalamo-cortical projections. Cerebellar circuits have also numerous anatomical and functional interactions with brainstem nuclei and projects also directly to the spinal cord. Cerebellar lesions alter the excitability of peripheral motor axons as demonstrated by peripheral motor threshold-tracking techniques in cerebellar stroke. The biophysical changes are correlated with the functional scores. Nerve excitability measurements represent an attractive tool to extract the rules underlying the tuning of excitability of the motor pathways by the cerebellum and to discover the contributions of each cerebellar nucleus in this key function, contributing to early plasticity and sensorimotor learning.

  18. A Framework to Survey the Energy Efficiency of Installed Motor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Prakash; Hasanbeigi, Ali; McKane, Aimee

    2013-08-01

    While motors are ubiquitous throughout the globe, there is insufficient data to properly assess their level of energy efficiency across regional boundaries. Furthermore, many of the existing data sets focus on motor efficiency and neglect the connected drive and system. Without a comprehensive survey of the installed motor system base, a baseline energy efficiency of a country or region’s motor systems cannot be developed. The lack of data impedes government agencies, utilities, manufacturers, distributers, and energy managers when identifying where to invest resources to capture potential energy savings, creating programs aimed at reducing electrical energy consumption, or quantifying the impacts of such programs. This paper will outline a data collection framework for use when conducting a survey under a variety of execution models to characterize motor system energy efficiency within a country or region. The framework is intended to standardize the data collected ensuring consistency across independently conducted surveys. Consistency allows for the surveys to be leveraged against each other enabling comparisons to motor system energy efficiencies from other regions. In creating the framework, an analysis of various motor driven systems, including compressed air, pumping, and fan systems, was conducted and relevant parameters characterizing the efficiency of these systems were identified. A database using the framework will enable policymakers and industry to better assess the improvement potential of their installed motor system base particularly with respect to other regions, assisting in efforts to promote improvements to the energy efficiency of motor driven systems.

  19. Plasticity of motor control systems demonstrated by yoga training.

    Science.gov (United States)

    Telles, S; Hanumanthaiah, B H; Nagarathna, R; Nagendra, H R

    1994-04-01

    The static motor performance was tested in two groups with 20 subjects in each (age range 17 to 22 years, and 5 females in each group). Tests were carried out at the beginning and end of a 10 day period. The test required being able to insert and hold a metal stylus within holes of varying sizes for 15 sec. Accidental contacts between the stylus and the sides of the holes, were registered on a counter as errors. During the 10 days one group (the yoga group) practised asanas (physical postures), pranayama (voluntary regulation of breathing), meditation, devotional sessions, and tratakas (visual focussing exercises). The control group followed their usual routine. At the end of 10 days the yoga group showed a significant reduction in number of errors (Wilcoxon paired signed ranks test), while the control group did not change. Our earlier study showed a similar improvement in children (9-13 years). It was interesting to note the same degree of plasticity in motor control systems in young adults. The implications for rehabilitation programmes have been discussed.

  20. A New Approach to Laboratory Motor Control MMCS: The Modular Motor Control System

    Science.gov (United States)

    1989-02-01

    encB2 encl2 h/beat2 J2 . h/ beatl encll encBl encAl 0 = LED indicator connectors to motor/enc Figure 5.2: Motor interface board layout something is...signal for joint 1. h/ beatl Green Heartbeat signal for joint 1. h/beat2 Green Heartbeat signal for joint 2. gpl Red General purpose (software controllable

  1. Continuous theta-burst stimulation of the primary motor cortex in essential tremor.

    Science.gov (United States)

    Hellriegel, Helge; Schulz, Eva M; Siebner, Hartwig R; Deuschl, Günther; Raethjen, Jan H

    2012-05-01

    We investigated whether essential tremor (ET) can be altered by suppressing the corticospinal excitability in the primary motor cortex (M1) with transcranial magnetic stimulation. 10 Patients with ET and 10 healthy controls underwent transcranial continuous theta-burst stimulation (cTBS) of the left primary motor hand area at 80% (real cTBS) and 30% (control cTBS) of active motor threshold in two separate sessions at least one week apart. Postural tremor was rated clinically and measured accelerometrically before and after cTBS. Corticospinal excitability was assessed by recording the motor evoked potentials (MEP) from the first dorsal interosseous muscle. Real cTBS but not control cTBS reduced the tremor total power assessed with accelerometry. This beneficial effect was subclinical as there were no significant changes in clinical tremor rating after real cTBS. Relative to control cTBS, real cTBS reduced corticospinal excitability in the stimulated primary motor cortex only in healthy controls but not in ET patients. Real cTBS has a beneficial effect on ET. Since cTBS did not induce a parallel reduction in corticospinal excitability, this effect was not mediated by a suppression of the corticospinal motor output. "Inhibitory" cTBS of M1 leads to a consistent but subclinical reduction in tremor amplitude. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  2. 'Motor challenge' pilot programme; Motor Challenge Pilotprogramm. Schweizer Teilnahme im SAVE-Programm: pilot actions for motor systems industrial energy use challenge

    Energy Technology Data Exchange (ETDEWEB)

    Nipkow, J.

    2003-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a pilot project associated with the Motor Challenge Programme (MCP) initiated by the European Commission (Transport and Energy Committee). The programme is briefly described, which aims to improve the efficiency of electrical motors used in industrial compressed-air, pump and ventilator systems as well as in comprehensive motor driven systems. Switzerland's participation in this pilot project is examined, which was concluded after a period of two years when the Motor Challenge Programme itself was launched in February 2003. The mechanisms of the programme are described, whereby companies may become involved in the programme either as partners (users of drive systems) or as endorsers (suppliers, planners, etc., of such systems). Experience gained with two companies in Switzerland - a food processing group and a major chemical pulp producer - who participated in the programme is presented. Efficiency potentials of around 3 GWh/a were identified; these represent a high proportion of the estimated total of 18 GWh/a in the overall programme. A follow-up project is proposed that is to provide detailed information and initiate further efficiency projects in order to encourage other companies to participate in the MCP programme.

  3. Age and muscle-dependent variations in corticospinal excitability during standing tasks.

    Directory of Open Access Journals (Sweden)

    Anthony Remaud

    Full Text Available In this study, we investigated how modulation in corticospinal excitability elicited in the context of standing tasks varies as a function of age and between muscles. Changes in motor evoked potentials (MEPs recorded in tibialis anterior (TA and gastrocnemius lateralis (GL were monitored while participants (young, n = 10; seniors, n = 11 either quietly stood (QS or performed a heel raise (HR task. In the later condition, transcranial magnetic stimulation (TMS pulses were delivered at three specific time points during the task: 1 250 ms before the "go" cue (preparatory (PREP phase, 2 100 ms before the heel rise (anticipatory postural adjustment (APA phase, and 3 200 ms after heel rise (execution (EXEC phase. In each task and each phase, variations in MEP characteristics were analysed for age and muscle-dependent effects. Variations in silent period (SP duration were also examined for certain phases (APA and EXEC. Our analysis revealed no major difference during QS, as participants exhibited very similar patterns of modulation in both TA and GL, irrespective of their age group. During the HR task, young adults exhibited a differential modulation in the PREP phase with enhanced responses in TA relative to GL, which was not seen in seniors. Finally, besides differences in MEP latency, age had little influence on MEP modulation during the APA and EXEC phases, where amplitude was largely a function of background muscle activity associated with each phase (i.e., APA: TA; EXEC: GL. No age or muscle effects were detected for SP measurements. Overall, our results revealed no major differences between young adults and healthy seniors in the ability to modulate corticospinal facilitation destined to ankle muscles during standing tasks, with maybe the exception of the ability to prime muscle synergies in the preparatory phase of action.

  4. Autonomic nervous system correlates in movement observation and motor imagery

    Directory of Open Access Journals (Sweden)

    Christian eCollet

    2013-07-01

    Full Text Available The purpose of the current article is to provide a comprehensive overview of the literature offering a better understanding on the autonomic nervous system (ANS correlates in motor imagery (MI and movement observation. These are two high brain functions involving sensori-motor coupling, mediated by memory systems. How observing or mentally rehearsing a movement affect ANS activity has not been extensively investigated. The links between cognitive functions and ANS responses are not so obvious. We first describe the organization of the ANS whose main purposes are controlling vital functions by maintaining the homeostasis of the organism and providing adaptive responses when changes occur either in the external or internal milieu. We will then review how scientific knowledge evolved, thus integrating recent findings related to ANS functioning, and show how these are linked to mental functions. In turn, we will describe how movement observation or MI may elicit physiological responses at the peripheral level of the autonomic effectors, thus eliciting autonomic correlates to cognitive activity. Key features of this paper are to draw a step-by step progression from the understanding of ANS physiology to its relationships with high mental processes such as movement observation or MI. We will further provide evidence that mental processes are co-programmed both at the somatic and autonomic levels of the central nervous system. We will thus detail how peripheral physiological responses may be analyzed to provide objective evidence that MI is actually performed. The main perspective is thus to consider that, during movement observation and MI, ANS activity is an objective witness of mental processes.

  5. Passive control of Permanent Magnet Synchronous Motor chaotic system based on state observer

    Institute of Scientific and Technical Information of China (English)

    QI Dong-lian; WANG Qiao

    2006-01-01

    Passive system theory was applied to propose a new passive control method with nonlinear observer of the Permanent Magnet Synchronous Motor chaotic system. Through constructing a Lyapunov function, the subsystem of the Permanent Magnet Synchronous Motor chaotic system could be proved to be globally stable at the equilibrium point. Then a controller with smooth state feedback is designed so that the Permanent Magnet Synchronous Motor chaotic system can be equivalent to a passive system.To get the state variables of the controller, the nonlinear observer is also studied. It is found that the outputs of the nonlinear observer can approximate the state variables of the Permanent Magnet Synchronous Motor chaotic system if the system's nonlinear function is a globally Lipschitz function. Simulation results showed that the equivalent passive system of Permanent Magnet Synchronous Motor chaotic system could be globally asymptotically stabilized by smooth state feedback in the observed parameter convergence condition area.

  6. 75 FR 23306 - Establishment of Advisory Committee on the National Motor Vehicle Title Information System

    Science.gov (United States)

    2010-05-03

    ... Information System AGENCY: Office of Justice Programs (OJP), Justice. ACTION: Notice of establishment of the National Motor Vehicle Title Information System (NMVTIS) Advisory Board. SUMMARY: Pursuant to the National Motor Vehicle Title Information System (NMVTIS) Final Rule, 74 FR 5740, 5774 (January 30, 2009)...

  7. CSF neurofilament light chain reflects corticospinal tract degeneration in ALS

    OpenAIRE

    Menke, Ricarda A.L.; Gray, Elizabeth; Lu, Ching-Hua; Kuhle, Jens; Talbot, Kevin; Malaspina, Andrea; Turner, Martin R.

    2015-01-01

    Objective Diffusion tensor imaging (DTI) is sensitive to white matter tract pathology. A core signature involving the corticospinal tracts (CSTs) has been identified in amyotrophic lateral sclerosis (ALS). Raised neurofilament light chain protein (NfL) in cerebrospinal fluid (CSF) is thought to reflect axonal damage in a range of neurological disorders. The relationship between these two measures was explored. Methods CSF and serum NfL concentrations and DTI acquired at 3?Tesla on the same da...

  8. Resting-state interhemispheric motor connectivity and white matter integrity correlate with motor impairment in chronic stroke

    Directory of Open Access Journals (Sweden)

    Joyce L Chen

    2013-11-01

    Full Text Available Functional and structural reorganization in the brain occurs after stroke. The ability to predict motor outcomes may depend on patterns of brain functional and structural connectivity. We tested the hypothesis that alterations in motor transcallosal and corticospinal connections correlate with motor impairment in patients with chronic stroke. Eleven ischemic stroke patients underwent the Upper Extremity Fugl Meyer assessment, resting state functional magnetic resonance imaging, and diffusion tensor imaging. Twelve healthy control subjects underwent diffusion tensor imaging. We assessed the temporal coupling in neural activity between interhemispheric motor cortex, and white matter integrity by means of fractional anisotropy, in the transcallosal motor fibers and corticospinal tract. Partial correlation analyses were performed to determine whether these connectivity measures correlate with Upper Extremity Fugl Meyer scores. Patients compared to controls had reduced fractional anisotropy in common voxels of transcallosal motor and ipsilesional corticospinal fibers. Within the patient group those with higher interhemispheric motor cortex connectivity and higher fractional anisotropy in the transcallosal motor fibers were less impaired. The results show that markers of functional and structural motor cortex connectivity correlate with motor impairment in the chronic stage of stroke.

  9. ADC evaluation of the corticospinal tract in multiple sclerosis.

    Science.gov (United States)

    Inal, Mikail; Unal, Birsen; Kala, Ibrahim; Turkel, Yakup; Bilgili, Yasemin Karadeniz

    2015-06-01

    Apparent diffusion coefficient (ADC) values derived from diffusion-weighted MR imaging (DWI) provide important information about tissues. The goal of this study was to evaluate the ADC values in the corticospinal tract regions in multiple sclerosis (MS). The ADC values of 42 patients with multiple sclerosis and 46 healthy people were measured. The ADC values in the corticospinal tract at the capsula interna posterior crus from six points and mesencephalon from three points bilaterally in MS patients were compared with those of controls. An ANOVA post hoc test was used to analyse the differences in mean ADC values between the MS and control groups. The mean ADC values of the right (p = 0.008) and left internal capsules (p = 0.000) and right (p = 0.002) and left mesencephalons (p = 0.044) in MS patients were significantly lower than in the control group. There was no significant difference between the right and left side ADC values in MS (p = 0.313 vs. p = 0.223) and control groups (p = 0.756 vs. p = 0.105), respectively. The mean ADC values of the corticospinal tract in MS patients were significantly lower than in the control group. This decreased diffusion may be the result of cellular infiltration due to inflammation, cytotoxic oedema, demyelination or remyelination processes.

  10. Continuous Energy Improvement in Motor Driven Systems - A Guidebook for Industry

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert A. McCoy and John G. Douglass

    2014-02-01

    This guidebook provides a step-by-step approach to developing a motor system energy-improvement action plan. An action plan includes which motors should be repaired or replaced with higher efficiency models, recommendations on maintaining a spares inventory, and discussion of improvements in maintenance practices. The guidebook is the successor to DOE’s 1997 Energy Management for Motor Driven Systems. It builds on its predecessor publication by including topics such as power transmission systems and matching driven equipment to process requirements in addition to motors.

  11. Differential effects of motor cortical excitability and plasticity in young and old individuals: a Transcranial Magnetic Stimulation (TMS study

    Directory of Open Access Journals (Sweden)

    Shahid eBashir

    2014-06-01

    Full Text Available Aging is associated with changes in the motor system that, over time, can lead to functional impairments and contribute negatively to the ability to recover after brain damage. Unfortunately, there are still many questions surrounding the physiological mechanisms underlying these impairments. We examined cortico-spinal excitability and plasticity in a young cohort (age range: 19-31 and an elderly cohort (age range: 47-73 of healthy right-handed individuals using navigated transcranial magnetic stimulation (nTMS. Subjects were evaluated with a combination of physiological (motor evoked potentials (MEPs, motor threshold (MT, intracortical inhibition (ICI, intracortical facilitation (ICF, and silent period (SP and behavioral (reaction time (RT, pinch force, 9 hole peg task (HPT measures at baseline and following one session of low-frequency (1 Hz navigated repetitive TMS (rTMS to the right (non-dominant hemisphere.In the young cohort, the inhibitory effect of 1 Hz rTMS was significantly in the right hemisphere and a significant facilitatory effect was noted in the unstimulated hemisphere. Conversely, in the elderly cohort, we report only a trend toward a facilitatory effect in the unstimulated hemisphere, suggesting reduced cortical plasticity and interhemispheric commuinication. To this effect, we show that significant differences in hemispheric cortico-spinal excitability were present in the elderly cohort at baseline, with significantly reduced cortico-spinal excitability in the right hemisphere as compared to the left hemisphere. A correlation analysis revealed no significant relationship between cortical thickness of the selected region of interest and MEPs in either young or old subjects prior to and following rTMS. When combined with our preliminary results, further research into this topic could lead to the development of neurophysiological markers pertinent to the diagnosis, prognosis, and treatment of neurological

  12. Modulation of corticospinal excitability during lengthening and shortening contractions in the first dorsal interosseus muscle of humans.

    Science.gov (United States)

    Sekiguchi, Hirofumi; Kohno, Yutaka; Hirano, Tatsuya; Akai, Masami; Nakajima, Yasoichi; Nakazawa, Kimitaka

    2007-04-01

    Lengthening and shortening contractions are the fundamental patterns of muscle activation underlying various movements. It is still unknown whether or not there is a muscle-specific difference in such a fundamental pattern of muscle activation. The purpose of this study was, therefore, to investigate whether or not the relationship between lengthening and shortening contractions in the modulation of corticospinal excitability in the first dorsal interosseus (FDI) muscle is the same as that of previously tested muscles because the hand muscles are anatomically and functionally different from the other muscles. To this end, we investigated the relationship between the input-output curves of the corticospinal pathway (i.e., the relationship between the stimulus intensities vs. the area of motor-evoked potentials) during lengthening and shortening contractions in 17 healthy subjects. The shape of this relationship was sigmoidal and characterized by a plateau value, maximum slope, and threshold. The plateau value was at the same level between lengthening and shortening contractions. However, the maximum slope (P shortening contractions. These findings were different from the results of other muscles tested in previous studies (i.e., the soleus muscle and the elbow flexors). That is to say, the plateau value and the maximum slope during lengthening contractions were significantly lower than those during shortening contractions in previous studies. This study provides tentative evidence that the relationship between lengthening and shortening contractions in the modulation of corticospinal excitability differs between muscles, indicating that the underlying neural control is not necessarily the same even though the fundamental patterns of muscle activation are carried out.

  13. Plasminogen deficiency causes reduced corticospinal axonal plasticity and functional recovery after stroke in mice.

    Directory of Open Access Journals (Sweden)

    Zhongwu Liu

    Full Text Available Tissue plasminogen activator (tPA has been implicated in neurite outgrowth and neurological recovery post stroke. tPA converts the zymogen plasminogen (Plg into plasmin. In this study, using plasminogen knockout (Plg-/- mice and their Plg-native littermates (Plg+/+, we investigated the role of Plg in axonal remodeling and neurological recovery after stroke. Plg+/+ and Plg-/- mice (n = 10/group were subjected to permanent intraluminal monofilament middle cerebral artery occlusion (MCAo. A foot-fault test and a single pellet reaching test were performed prior to and on day 3 after stroke, and weekly thereafter to monitor functional deficit and recovery. Biotinylated dextran amine (BDA was injected into the left motor cortex to anterogradely label the corticospinal tract (CST. Animals were euthanized 4 weeks after stroke. Neurite outgrowth was also measured in primary cultured cortical neurons harvested from Plg+/+ and Plg-/- embryos. In Plg+/+ mice, the motor functional deficiency after stroke progressively recovered with time. In contrast, recovery in Plg-/- mice was significantly impaired compared to Plg+/+ mice (p0.82, p<0.01. Plg-/- neurons exhibited significantly reduced neurite outgrowth. Our data suggest that plasminogen-dependent proteolysis has a beneficial effect during neurological recovery after stroke, at least in part, by promoting axonal remodeling in the denervated spinal cord.

  14. Deterioration of pre-existing hemiparesis due to injury of the ipsilateral anterior corticospinal tract.

    Science.gov (United States)

    Jang, Sung Ho; Kwon, Hyeok Gyu

    2013-05-29

    The anterior corticospinal tract (CST) has been suggested as one of the ipsilateral motor pathways, which contribute to motor recovery following stroke. In this study, we report on a patient who showed deterioration of pre-existing hemiparesis due to an injury of the ipsilateral anterior CST following a pontine infarct, as evaluated by diffusion tensor tractography (DTT). A 55-year-old male patient showed quadriparesis after the onset of an infarct in the right pontine basis. He had history of an infarct in the left middle cerebral artery territory 7 years ago. Consequently, he showed right hemiparesis before onset of the right pontine infarct. Following this, his right hemiparesis deteriorated whereas his left hemiparesis newly developed. The DTTs for whole CST of the right hemisphere in the patient and both hemispheres in control subjects descended through the known CST pathway. By contrast, the DTT for the left whole CST of the patient showed a complete injury finding. The DTTs for the anterior CST of control subjects passed through the known pathway of the CST from cerebral cortex to medulla and terminated in the anterior funiculus of the upper cervical cord. However, the DTT for right anterior CST in the patient showed discontinuation below the right pontine infarct. It appeared that the deterioration of the pre-existing right hemiparesis was ascribed to an injury of the right anterior CST due to the right pontine infarct.

  15. Muscle Relaxation of the Foot Reduces Corticospinal Excitability of Hand Muscles and Enhances Intracortical Inhibition

    Science.gov (United States)

    Kato, Kouki; Muraoka, Tetsuro; Mizuguchi, Nobuaki; Nakagawa, Kento; Nakata, Hiroki; Kanosue, Kazuyuki

    2016-01-01

    The object of this study was to clarify the effects of foot muscle relaxation on activity in the primary motor cortex (M1) of the hand area. Subjects were asked to volitionally relax the right foot from sustained contraction of either the dorsiflexor (tibialis anterior; TA relaxation) or plantarflexor (soleus; SOL relaxation) in response to an auditory stimulus. Single- and paired-pulse transcranial magnetic stimulation (TMS) was delivered to the hand area of the left M1 at different time intervals before and after the onset of TA or SOL relaxation. Motor evoked potentials (MEPs) were recorded from the right extensor carpi radialis (ECR) and flexor carpi radialis (FCR). MEP amplitudes of ECR and FCR caused by single-pulse TMS temporarily decreased after TA and SOL relaxation onset, respectively, as compared with those of the resting control. Furthermore, short-interval intracortical inhibition (SICI) of ECR evaluated with paired-pulse TMS temporarily increased after TA relaxation onset. Our findings indicate that muscle relaxation of the dorsiflexor reduced corticospinal excitability of the ipsilateral hand muscles. This is most likely caused by an increase in intracortical inhibition. PMID:27242482

  16. Integrated Cooling System for Induction Motor Traction Drives, CARAT Program Phase Two Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Konrad, Charles E. [VPT, Inc., Blacksburg, VA (United States)

    2002-12-03

    This Program is directed toward improvements in electric vehicle/hybrid electric vehicle traction systems, and in particular, the development of a low cost, highly efficient, compact traction motor-controller system targeted for high volume automotive use. Because of the complex inter-relationships between the motor and the controller, the combination of motor and controller must be considered as a system in the design and evaluation of overall cost and performance. The induction motor is ideally suited for use as a traction motor because of its basic ruggedness, low cost, and high efficiency. As one can see in Figure 1.1, the induction motor traction drive has been continually evolving through a succession of programs spanning the past fifteen years. VPT marketed an induction motor-based traction drive system, the EV2000, which proved to be a reliable, high performance system that was used in a wide range of vehicles. The EV2000 drives evolved from the Modular Electric Vehicle Program (MEVP) and has been used in vehicles ranging in size from 3,000 lb. autos and utility vans, to 32,000 lb. city transit buses. Vehicles powered by the EV2000 induction motor powertrain have accumulated over 2 million miles of service. The EV2000 induction motor system represents 1993 state-of-the-art technology, and evolved from earlier induction motor programs that drove induction motor speeds up to 15,000 rpm to reduce the motor size and cost. It was recognized that the improvements in power density and motor cost sought in the PNGV program could only be achieved through increases in motor speed. Esson’s Rule for motor power clearly states that the power obtainable from a given motor design is the product of motor speed and volume. In order to meet the CARAT Program objectives, the maximum speed goal of the induction motor designed in this Program was increased from 15,000 rpm to 20,000 rpm while maintaining the efficiency and durability demonstrated by lower speed designs done in

  17. Cerebral activation is correlated to regional atrophy of the spinal cord and functional motor disability in spinal cord injured individuals

    DEFF Research Database (Denmark)

    Lundell, Henrik; Christensen, Mark Schram; Barthélemy, Dorothy

    2011-01-01

    Recovery of function following lesions in the nervous system requires adaptive changes in surviving circuitries. Here we investigate whether changes in cerebral activation are correlated to spinal cord atrophy and recovery of functionality in individuals with incomplete spinal cord injury (SCI). 19...... in the tibialis anterior muscle elicited by transcranial magnetic stimulation, but this did not reach statistical significance. There was no correlation between motor score or spinal cord dimensions and the volume of the cortical motor areas. The observations show that lesion of descending tracts in the lateral...... to the width of the spinal cord in the left-right direction, where the corticospinal tract is located, but not in the antero-posterior direction. There was a tendency for a negative correlation between cerebral activation in ipsilateral S1, M1 and PMC and the amplitude of motor evoked potentials...

  18. Power factor control system for ac induction motors

    Science.gov (United States)

    Nola, F. J. (Inventor)

    1981-01-01

    A power control circuit for an induction motor is disclosed in which a servo loop is used to control power input by controlling the power factor of motor operation. The power factor is measured by summing the voltage and current derived square wave signals.

  19. Physiological targets of artificial gravity: the sensory-motor system

    NARCIS (Netherlands)

    Groen, E.L.; Clarke, A.; Bles, W.; Wuyts, F.; Paloski, W.; Clément, G.

    2007-01-01

    This chapter describes the pros and cons of artificial gravity applications in relation to human sensory-motor functioning in space. Spaceflight creates a challenge for sensory-motor functions that depend on gravity, which include postural balance, locomotion, eye-hand coordination, and spatial orie

  20. Nouns Referring to Tools and Natural Objects Differentially Modulate the Motor System

    Science.gov (United States)

    Gough, Patricia M.; Riggio, Lucia; Chersi, Fabian; Sato, Marc; Fogassi, Leonardo; Buccino, Giovanni

    2012-01-01

    While increasing evidence points to a critical role for the motor system in language processing, the focus of previous work has been on the linguistic category of verbs. Here we tested whether nouns are effective in modulating the motor system and further whether different kinds of nouns--those referring to artifacts or natural items, and items…

  1. Co-Simulation of BLDC Motor Commutation by using MATLAB Simulink and Xilinx System generator

    Directory of Open Access Journals (Sweden)

    Suneeta

    2016-04-01

    Full Text Available This work mainly focuses on Matlab Simulink model for electronic commutation of BLDC motor and co simulation of the model by using Xilinx System generator tool. The BLDC motors (AKM21E are available in small size with good speed/torque characteristics. Since, the efficiency and dynamic response is high compared to brushed DC motor, they have widely used in various applications. We are using BLDC motor for adjusting the focus in radio telescope. The efficient electronic commutation is designed and tested by using modelling in Matlab Simulink. The Co verification of the model is done by using Xilinx system generator.

  2. ON NATURAL CHARACTERISTICS OF A RIGID MOTOR FLEXIBLE BASE DYNAMIC COUPLED SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Sun Yuguo; Song Kongjie

    2004-01-01

    In shipping and aircraft engineering,the vibrating motor or instrumentation is usually mounted on a non-rigid base.To apply isolation design effectively,it is necessary to investigate the nature vibration characteristics of the rigid motor,flexible base coupled system.A universal dynamic express for the coupled system is derived.A PC-based measurement solution is presented.And the system's dynamic behavior is then investigated numerically and experimentally.The results show that a strong interaction will exist between the motor's rigid mode and the flexible base's mode when the motor's mounting frequency is close to the flexible base's first natural frequency.The first natural frequency of the coupled system is generally lower than the motor's rigid mode frequency.At high frequency,the flexible base's modes are the dominant modes of the coupled system.

  3. Mechanism of cooperative behaviour in systems of slow and fast molecular motors.

    Science.gov (United States)

    Larson, Adam G; Landahl, Eric C; Rice, Sarah E

    2009-06-28

    Two recent theoretical advances have described cargo transport by multiple identical motors and by multiple oppositely directed, but otherwise identical motors [M. J. Muller, S. Klumpp and R. Lipowsky, Proc. Natl. Acad. Sci. U. S. A., 2008, 105(12), 4609-4614; S. Klumpp and R. Lipowsky, Proc. Natl. Acad. Sci. U. S. A., 2005, 102(48), 17284-17289]. Here, we combine a similar theoretical approach with a simple experiment to describe the behaviour of a system comprised of slow and fast molecular motors having the same directionality. We observed the movement of microtubules by mixtures of slow and fast kinesin motors attached to a glass coverslip in a classic sliding filament assay. The motors are identical, except that the slow ones contain five point mutations that collectively reduce their velocity approximately 15-fold without compromising maximal ATPase activity. Our results indicate that a small fraction of fast motors are able to accelerate the dissociation of slow motors from microtubules. Because of this, a sharp, highly cooperative transition occurs from slow to fast microtubule movement as the relative number of fast motors in the assay is increased. Microtubules move at half-maximal velocity when only 15% of the motors in the assay are fast. Our model indicates that this behaviour depends primarily on the relative motor velocities and the asymmetry between their forward and backward dissociation forces. It weakly depends on the number of motors and their processivity. We predict that movement of cargoes bound to two types of motors having very different velocities will be dominated by one or the other motor. Therefore, cargoes can potentially undergo abrupt changes in movement in response to regulatory mechanisms acting on only a small fraction of motors.

  4. CB1 receptor antagonism/inverse agonism increases motor system excitability in humans.

    Science.gov (United States)

    Oliviero, A; Arevalo-Martin, A; Rotondi, M; García-Ovejero, D; Mordillo-Mateos, L; Lozano-Sicilia, A; Panyavin, I; Chiovato, L; Aguilar, J; Foffani, G; Di Lazzaro, V; Molina-Holgado, E

    2012-01-01

    CB1 receptor is highly expressed in cerebral structures related to motor control, such as motor cortex, basal ganglia and cerebellum. In the spinal cord, the expression of CB1 receptors has also been observed in ventral motor neurons, interneurons and primary afferents, i.e., in the cells that may be part of the circuits involved in motor control. It is known that the antagonist/inverse agonist of CB1 receptors Rimonabant penetrates the blood-brain barrier and produces a broad range of central psychoactive effects in humans. Based on the occurrence of central effects in humans treated with Rimonabant and on the location of CB1 receptors, we hypothesized that the application of Rimonabant can also affect the motor system. We tested the effects of a single dose of 20mg of Rimonabant on the excitability of motor cortex and of spinal motor neurons in order to detect a possible drug action on motor system at cortical and spinal levels. For this purpose we use classical protocols of transcranial magnetic and electrical stimulation (TMS and TES). Single and paired pulse TMS and TES were used to assess a number of parameters of cortical inhibition and cortical excitability as well as of the excitability of spinal motor neurons. We demonstrated that a single oral dose of 20mg of Rimonabant can increase motor system excitability at cortical and spinal levels. This opens new avenues to test the CB1R antagonists/inverse agonists for the treatment of a number of neurological dysfunctions in which can be useful to increase the excitability levels of motor system. Virtually all the disorders characterized by a reduced output of the motor cortex can be included in the list of the disorders that can be treated using CB1 antagonists/reverse agonists (e.g. stroke, traumatic brain injury, spinal cord injury, multiple sclerosis, fatigue syndromes, parkinsonisms, etc.). Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Application of drive circuit based on L298N in direct current motor speed control system

    Science.gov (United States)

    Yin, Liuliu; Wang, Fang; Han, Sen; Li, Yuchen; Sun, Hao; Lu, Qingjie; Yang, Cheng; Wang, Quanzhao

    2016-10-01

    In the experiment of researching the nanometer laser interferometer, our design of laser interferometer circuit system is up to the wireless communication technique of the 802.15.4 IEEE standard, and we use the RF TI provided by Basic to receive the data on speed control system software. The system's hardware is connected with control module and the DC motor. However, in the experiment, we found that single chip microcomputer control module is very difficult to drive the DC motor directly. The reason is that the DC motor's starting and braking current is larger than the causing current of the single chip microcomputer control module. In order to solve this problem, we add a driving module that control board can transmit PWM wave signal through I/O port to drive the DC motor, the driving circuit board can come true the function of the DC motor's positive and reversal rotation and speed adjustment. In many various driving module, the L298N module's integrated level is higher compared with other driver module. The L298N model is easy to control, it not only can control the DC motor, but also achieve motor speed control by modulating PWM wave that the control panel output. It also has the over-current protection function, when the motor lock, the L298N model can protect circuit and motor. So we use the driver module based on L298N to drive the DC motor. It is concluded that the L298N driver circuit module plays a very important role in the process of driving the DC motor in the DC motor speed control system.

  6. Motor-Evoked Potentials in the Lower Back Are Modulated by Visual Perception of Lifted Weight.

    Directory of Open Access Journals (Sweden)

    Frank Behrendt

    Full Text Available Facilitation of the primary motor cortex (M1 during the mere observation of an action is highly congruent with the observed action itself. This congruency comprises several features of the executed action such as somatotopy and temporal coding. Studies using reach-grasp-lift paradigms showed that the muscle-specific facilitation of the observer's motor system reflects the degree of grip force exerted in an observed hand action. The weight judgment of a lifted object during action observation is an easy task which is the case for hand actions as well as for lifting boxes from the ground. Here we investigated whether the cortical representation in M1 for lumbar back muscles is modulated due to the observation of a whole-body lifting movement as it was shown for hand action. We used transcranial magnetic stimulation (TMS to measure the corticospinal excitability of the m. erector spinae (ES while subjects visually observed the recorded sequences of a person lifting boxes of different weights from the floor. Consistent with the results regarding hand action the present study reveals a differential modulation of corticospinal excitability despite the relatively small M1 representation of the back also for lifting actions that mainly involve the lower back musculature.

  7. Specific modulation of corticospinal and spinal excitabilities during maximal voluntary isometric, shortening and lengthening contractions in synergist muscles.

    Science.gov (United States)

    Duclay, Julien; Pasquet, Benjamin; Martin, Alain; Duchateau, Jacques

    2011-06-01

    This study was designed to investigate the cortical and spinal mechanisms involved in the modulations of neural activation during lengthening compared with isometric and shortening maximal voluntary contractions (MVCs). Two muscles susceptible to different neural adjustments at the spinal level, the soleus (SOL) and medial gastrocnemius (MG), were compared. Twelve healthy males participated in at least two experimental sessions designed to assess corticospinal and spinal excitabilities. We compared the modulation of motor evoked potentials (MEPs) in response to transcranial magnetic stimulation and Hoffmann reflexes (H-reflexes) during isometric and anisometric MVCs. The H-reflex and MEP responses, recorded during lengthening and shortening MVCs, were compared with those obtained during isometric MVCs. The results indicate that the maximal amplitude of both MEP and H-reflex in the SOL were smaller (P shortening MVCs but similar (P > 0.05) in MG for all three muscle contraction types. The silent period that follows maximal MEPs was reduced (P muscle. Collectively, the current results indicate that the relative contribution of both cortical and spinal mechanisms to the modulation of neural activation differs during lengthening MVCs and between two synergist muscles. The comparison of SOL and MG responses further suggests that the specific modulation of the corticospinal excitability during lengthening MVCs depends mainly on pre- and postsynaptic inhibitory mechanisms acting at the spinal level.

  8. Development of a Superconducting Magnet System for the ONR/General Atomics Homopolar Motor

    Science.gov (United States)

    Schaubel, K. M.; Langhorn, A. R.; Creedon, W. P.; Johanson, N. W.; Sheynin, S.; Thome, R. J.

    2006-04-01

    This paper describes the design, testing and operational experience of a superconducting magnet system presently in use on the Homopolar Motor Program. The homopolar motor is presently being tested at General Atomics in San Diego, California for the U.S Navy Office of Naval Research. The magnet system consists of two identical superconducting solenoid coils housed in two cryostats mounted integrally within the homopolar motor housing. The coils provide the static magnetic field required for motor operation and are wound using NbTi superconductor in a copper matrix. Each magnet is conduction cooled using a Gifford McMahon cryocooler. The coils are in close proximity to the iron motor housing requiring a cold to warm support structure with high stiffness and strength. The design of the coils, cold to warm support structure, cryogenic system, and the overall magnet system design will be described. The test results and operational experience will also be described.

  9. System and method for determining stator winding resistance in an AC motor

    Science.gov (United States)

    Lu, Bin; Habetler, Thomas G.; Zhang, Pinjia; Theisen, Peter J.

    2011-05-31

    A system and method for determining stator winding resistance in an AC motor is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of an AC motor. The circuit includes at least one contactor and at least one switch to control current flow and terminal voltages in the AC motor. The system also includes a controller connected to the circuit and configured to modify a switching time of the at least one switch to create a DC component in an output of the system corresponding to an input to the AC motor and determine a stator winding resistance of the AC motor based on the injected DC component of the voltage and current.

  10. Motor pathway degeneration in young ataxia telangiectasia patients: A diffusion tractography study

    Directory of Open Access Journals (Sweden)

    Ishani Sahama

    2015-01-01

    Conclusions: Whole tract analysis of the corticomotor, corticospinal and somatosensory pathways in ataxia telangiectasia showed significant white matter degeneration along the entire length of motor circuits, highlighting that ataxia–telangiectasia gene mutation impacts the cerebellum and multiple other motor circuits in young patients.

  11. Development of Heat Dissipation Measuring System for 1.2-kW BLDC Motor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Injun; Ye, Jungwoo; Lee, Daehun; Hwang, Pyung; Shim, Jaesool [Yeungnam Univ., Gyeongsan (Korea, Republic of)

    2013-11-15

    In this study, a heat dissipation measurement system is developed to analyze a 1.2-kW BLDC motor. It is important to check the temperature of the motor because an increase in temperature causes problems in the motor insulations, which in turn influences the motor life. A generator for a vehicle is installed to set up a load. We changed the load from 165 to 495 W. While the rpm varies from 2000 to 4000 under various load conditions, the changes in temperature were measured for the operating period by using a thermocouple. The results of experiments conducted under natural convection conditions suggest that the temperature was not stationary with the rpm, load, and coil of the motor and it kept increasing over 120 .deg. C. However, under forced convection conditions, the temperature stationarily reached 84 .deg. C after 4000 s. The difference between the maximum and the minimum temperatures was 10.26 .deg. C with an increase in the rpm and load. The orders of high temperature were as follows: motor coil, side of motor surface, inside of motor cap, upper side of motor surface, and inner wall of the motor.

  12. The performance and efficiency of four motor/controller/battery systems for the simpler electric vehicles

    Science.gov (United States)

    Shipps, P. R.

    1980-05-01

    A test and analysis program performed on four complete propulsion systems for an urban electric vehicle (EV) is described and results given. A dc series motor and a permanent magnet (PM) motor were tested, each powered by an EV battery pack and controlled by (1) a series/parallel voltage-switching (V-switch) system; and (2) a system using a pulse width modulation, 400 Hz transistorized chopper. Dynamometer tests were first performed, followed by eV performance predictions and data correlating road tests. During dynamometer tests using chopper control; current, voltage, and power were measured on both the battery and motor sides of the chopper, using three types of instrumentation. Conventional dc instruments provided adequate accuracy for eV power and energy measurements, when used on the battery side of the controller. When using the chopper controller, the addition of a small choke inductor improved system efficiency in the lower duty cycle range (some 8% increase at 50% duty cycle) with both types of motors. Overall system efficiency rankings during road tests were: (1) series motor with V-switch; (2) PM motor with V-switch; (3) series motor with chopper; and (4) PM motor with chopper. Chopper control of the eV was smoother and required less driver skill than V-switch control.

  13. System Cost Analysis for an Interior Permanent Magnet Motor

    Energy Technology Data Exchange (ETDEWEB)

    Peter Campbell

    2008-08-01

    The objective of this program is to provide an assessment of the cost structure for an interior permanent magnet ('IPM') motor which is designed to meet the 2010 FreedomCAR specification. The program is to evaluate the range of viable permanent magnet materials for an IPM motor, including sintered and bonded grades of rare earth magnets. The study considers the benefits of key processing steps, alternative magnet shapes and their assembly methods into the rotor (including magnetization), and any mechanical stress or temperature limits. The motor's costs are estimated for an annual production quantity of 200,000 units, and are broken out into such major components as magnetic raw materials, processing and manufacturing. But this is essentially a feasibility study of the motor's electromagnetic design, and is not intended to include mechanical or thermal studies as would be done to work up a selected design for production.

  14. Speed Estimation of Induction Motor Using Model Reference Adaptive System with Kalman Filter

    Directory of Open Access Journals (Sweden)

    Pavel Brandstetter

    2013-01-01

    Full Text Available The paper deals with a speed estimation of the induction motor using observer with Model Reference Adaptive System and Kalman Filter. For simulation, Hardware in Loop Simulation method is used. The first part of the paper includes the mathematical description of the observer for the speed estimation of the induction motor. The second part describes Kalman filter. The third part describes Hardware in Loop Simulation method and its realization using multifunction card MF 624. In the last section of the paper, simulation results are shown for different changes of the induction motor speed which confirm high dynamic properties of the induction motor drive with sensorless control.

  15. High temperature brushless DC motor system and its operation mode control

    Institute of Scientific and Technical Information of China (English)

    邹继斌; 胡建辉; 徐永向

    2001-01-01

    The high temperature ( 175 ℃ ) operation of a motor spells out special requirements for control algorithms, materials and elements. The stability of motor characteristic is guaranteed by the digital control strategy. Constant velocity operation is achieved by phase-locked loop ( PLL), and constant power operation is achieved by a current-restricting circuit. A motor for constant speed and constant power operation has been built and the speed control system is tuned by MATLAB simulation. Experimental and simulation results for operation mode control of brushless DC motor are presented.

  16. Research on motor rotational speed measurement in regenerative braking system of electric vehicle

    Science.gov (United States)

    Pan, Chaofeng; Chen, Liao; Chen, Long; Jiang, Haobin; Li, Zhongxing; Wang, Shaohua

    2016-01-01

    Rotational speed signals acquisition and processing techniques are widely used in rotational machinery. In order to realized precise and real-time control of motor drive and regenerative braking process, rotational speed measurement techniques are needed in electric vehicles. Obtaining accurate motor rotational speed signal will contribute to the regenerative braking force control steadily and realized higher energy recovery rate. This paper aims to develop a method that provides instantaneous speed information in the form of motor rotation. It addresses principles of motor rotational speed measurement in the regenerative braking systems of electric vehicle firstly. The paper then presents ideal and actual Hall position sensor signals characteristics, the relation between the motor rotational speed and the Hall position sensor signals is revealed. Finally, Hall position sensor signals conditioning and processing circuit and program for motor rotational speed measurement have been carried out based on measurement error analysis.

  17. A Study on New Current Controller for 7-Phase BLDC Motor Drive System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Surk; Jeon, Ywun Seok; Mok, Hyung Soo [Konkuk University (Korea); Kim, Duk Keun [Komotek Co., Ltd. (Korea)

    2001-04-01

    Recently, the demand of motor for industrial, household machinery is increasing. As Switching devices and control technology are progressing, so the use of BLDC Motor is increasing. But 3-phase BLCD Motor generally used has pulsating torque and speed variation in commutation, so the range of its application is limited to high speed operation. Especially, to solve these problems, it is necessary to increase phase of Motor, so study of Poly-Phase BLDC Motor is progressing. However, when hysteresis current controller is used, switching frequency is highly increasing. In this paper, 7-Phase BLDC Motor drive system is designed. Also MSTC (Minimum Switching Time Controller) is proposed and with simulation and experiment, their validities are verified. (author). 10 refs., 26 figs., 1 tab.

  18. Design of motion adjusting system for space camera based on ultrasonic motor

    Science.gov (United States)

    Xu, Kai; Jin, Guang; Gu, Song; Yan, Yong; Sun, Zhiyuan

    2011-08-01

    Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper, some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system, which is composed of the drift adjusting mechanical frame, the ultrasonic motor, the driver of Ultrasonic Motor, the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor, photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system, was introduced the source of the disturbance, and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space, simple configuration, high position control precision, fine repeatability, self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent.

  19. SYSTEM OF BUSINESS-PROCESSES MANAGEMENT AT MOTOR-TRANSPORT ENTERPRISE

    OpenAIRE

    2010-01-01

    The place of the system of business-processes management at motor-transport enterprise in the general system of management of the enterprise has been substantiated. The subsystems of strategic management, business-processes management of strategic orientation and current activity, processes of enterprise functioning management have been marked out. The system of motor-transport enterprise business-processes management has been formed, which, unlike the existing ones, is based on the system-cy...

  20. Enhancing transcranial direct current stimulation via motor imagery and kinesthetic illusion: crossing internal and external tools.

    Science.gov (United States)

    Bodranghien, Florian; Manto, Mario; Lebon, Florent

    2016-06-01

    Transcranial direct current stimulation is a safe technique which is now part of the therapeutic armamentarium for the neuromodulation of motor functions and cognitive operations. It is currently considered that tDCS is an intervention that might promote functional recovery after a lesion in the central nervous system, thus reducing long-term disability and associated socio-economic burden. A recent study shows that kinesthetic illusion and motor imagery prolong the effects of tDCS on corticospinal excitability, overcoming one of the limitations of this intervention. Because changes in excitability anticipate changes in structural plasticity in the CNS, this interesting multi-modal approach might very soon find applications in neurorehabilitation.

  1. Continuous rotary motor electro-hydraulic servo system based on the improved repetitive controller

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-jing; JIANG ji-hai; LI Shang-yi

    2010-01-01

    In order to suppress the periodic interference of the continuous rotary electro-hydraulic servo motor,this paper makes the motor tracking the periodic signals with high accuracy,and improves the influence of friction interference to the performance of continuous rotary electro-hydraulic servo motor.The mathematic model of the electro-hydraulic position servo system of the continuous rotary motor was established,and the compound control method was adopted based on the repetitive control,feed forward and PID to suppress the friction interference.Through the simulation,the result confirms that the compound control method decreases the tracking error of the system,increases the robust performance of the system and improves the performance of the continuous rotary electro-hydraulic servo motor.

  2. 76 FR 55829 - Federal Motor Vehicle Safety Standards; Electronic Stability Control Systems

    Science.gov (United States)

    2011-09-09

    ... National Highway Traffic Safety Administration 49 CFR Part 571 RIN 2127-AL02 Federal Motor Vehicle Safety Standards; Electronic Stability Control Systems AGENCY: National Highway Traffic Safety Administration... changes to a new Federal motor vehicle safety standard requiring light vehicles to be equipped with...

  3. Influence of PWM Modes on Commutation Torque Ripples in Sensorless Brushless DC Motor Control System

    Institute of Scientific and Technical Information of China (English)

    ZHANGXiang-jun; CHENBo-shi; 等

    2001-01-01

    This paper introduces four PWM modes used in the sensorless brushless DC motor control system,analyzes their different influences on the commutation torque ripple in detail,and selects the best PWM mode in four given types to reduce commutation torque ripple of Brushless OC( BLDC) motors,Simulation and experimental results show that the selection is correct and practical.

  4. Degeneration of corpus callosum and recovery of motor function after stroke: a multimodal magnetic resonance imaging study.

    Science.gov (United States)

    Wang, Ling E; Tittgemeyer, Marc; Imperati, Davide; Diekhoff, Svenja; Ameli, Mitra; Fink, Gereon R; Grefkes, Christian

    2012-12-01

    Animal models of stroke demonstrated that white matter ischemia may cause both axonal damage and myelin degradation distant from the core lesion, thereby impacting on behavior and functional outcome after stroke. We here used parameters derived from diffusion magnetic resonance imaging (MRI) to investigate the effect of focal white matter ischemia on functional reorganization within the motor system. Patients (n = 18) suffering from hand motor deficits in the subacute or chronic stage after subcortical stroke and healthy controls (n = 12) were scanned with both diffusion MRI and functional MRI while performing a motor task with the left or right hand. A laterality index was employed on activated voxels to assess functional reorganization across hemispheres. Regression analyses revealed that diffusion MRI parameters of both the ipsilesional corticospinal tract (CST) and corpus callosum (CC) predicted increased activation of the unaffected hemisphere during movements of the stroke-affected hand. Changes in diffusion MRI parameters possibly reflecting axonal damage and/or destruction of myelin sheath correlated with a stronger bilateral recruitment of motor areas and poorer motor performance. Probabilistic fiber tracking analyses revealed that the region in the CC correlating with the fMRI laterality index and motor deficits connected to sensorimotor cortex, supplementary motor area, ventral premotor cortex, superior parietal lobule, and temporoparietal junction. The results suggest that degeneration of transcallosal fibers connecting higher order sensorimotor regions constitute a relevant factor influencing cortical reorganization and motor outcome after subcortical stroke. Copyright © 2011 Wiley Periodicals, Inc.

  5. Abstract and concrete phrases processing differentially modulates cortico-spinal excitability.

    Science.gov (United States)

    Scorolli, Claudia; Jacquet, Pierre O; Binkofski, Ferdinand; Nicoletti, Roberto; Tessari, Alessia; Borghi, Anna M

    2012-12-07

    An important challenge of embodied theories is to explain the comprehension of abstract sentences. The aim of the present study was to scrutinize the role of the motor cortex in this process. We developed a new paradigm to study the abstract-concrete dimension by combining concrete (i.e., action-related) and abstract (i.e., non-action-related) verbs with nouns of graspable and non-graspable objects. Using these verb-noun combinations we performed a Transcranial Magnetic Stimulation (TMS) on the left primary motor cortex while participants performed a sentence sensibility task. Single-TMS pulses were delivered 250ms after verb or noun presentation in each of four combinations of abstract and concrete verbs and nouns. To evaluate cortico-spinal excitability we registered the electromyographic activity of the right first dorsal interosseous muscle. As to verb-noun integration, analysis of motor evoked potentials (MEPs) after TMS pulse during noun presentation revealed greater peak-to-peak amplitude in phrases containing abstract rather than concrete verbs. Response times were also collected and showed that compatible (Concrete-Concrete and Abstract-Abstract) combinations were processed faster than mixed ones; moreover in combinations containing concrete verbs, participants were faster when the pulse was delivered on the first word (verb) than on the second one (noun). Results support previous findings showing early activation of hand-related areas after concrete verbs processing. The prolonged or delayed activation of the same areas by abstract verbs will be discussed in the framework of recent embodied theories based on multiple types of representation, particularly theories emphasizing the role of different acquisition mechanisms for concrete and abstract words (Borghi and Cimatti, 2009,2012).

  6. Research on inverter test system of synchronous motor using modbus communication

    Science.gov (United States)

    Cao, Wenlun; Chen, Bei; He, Yuyao

    2013-03-01

    In this paper, the hardware architecture of the servo system composed by self-made inverter and permanent magnet synchronous motor is introduced as well as its measurement and control system software features. Basing on the Modbus-RTU protocols which contain the CRC data verification between IPC and the inverter, we have built a communication system. The measurement and control software of servo system are realized, which consists of self-made inverter and PMSM. Compared with the servo system which consists of Schindler's ATV31 inverter and SIMO's asynchronous motor, the results are given. The experiment parameters include harmonic content which is contained by phase current and voltage, and also the motor speed. The results show that the measurement and control system are stable and reliable. Both the harmonic content of the Inverter output and the motor speed meet the requirements.

  7. Backstepping Adaptive Controller of Electro-Hydraulic Servo System of Continuous Rotary Motor

    Institute of Scientific and Technical Information of China (English)

    XiaoJing Wang; ChangFu Xian; CaoLei Wan; JinBao Zhao; LiWei Xiu; AnCai Yu

    2014-01-01

    In order to consider the influence of the continuous rotary motor electro-hydraulic servo system parameters change on its performance, the design method of backstepping adaptive controller is put forward. The mathematical model of electro-hydraulic servo system of continuous rotary motor is established, and the whole system is decomposed into several lower order subsystems, and the virtual control signal is designed for each subsystem from the final subsystem with motor angular displacement to the subsystem with system control input voltage. Based on Lyapunov method and the backstepping theory, an adaptive backstepping controller is designed with the changed parameters adaptive law. It is proved that the system reaches the global asymptotic stability, and the system tracking error asymptotically tends to zero. The simulation results show that the backstepping adaptive controller based on the adaptive law of the changed parameters can improve the performance of continuous rotary motor, and the proposed control strategy is feasible.

  8. Specificity of motor components in the dual flagellar system of Shewanella putrefaciens CN-32.

    Science.gov (United States)

    Bubendorfer, Sebastian; Held, Susanne; Windel, Natalie; Paulick, Anja; Klingl, Andreas; Thormann, Kai M

    2012-01-01

    Bacterial flagellar motors are intricate nanomachines in which the stator units and rotor component FliM may be dynamically exchanged during function. Similar to other bacterial species, the gammaproteobacterium Shewanella putrefaciens CN-32 possesses a complete secondary flagellar system along with a corresponding stator unit. Expression of the secondary system occurs during planktonic growth in complex media and leads to the formation of a subpopulation with one or more additional flagella at random positions in addition to the primary polar system. We used physiological and phenotypic characterizations of defined mutants in concert with fluorescent microscopy on labelled components of the two different systems, the stator proteins PomB and MotB, the rotor components FliM(1) and FliM(2), and the auxiliary motor components MotX and MotY, to determine localization, function and dynamics of the proteins in the flagellar motors. The results demonstrate that the polar flagellum is driven by a Na(+)-dependent FliM(1)/PomAB/MotX/MotY flagellar motor while the secondary system is rotated by a H(+)-dependent FliM(2)/MotAB motor. The components were highly specific for their corresponding motor and are unlikely to be extensively swapped or shared between the two flagellar systems under planktonic conditions. The results have implications for both specificity and dynamics of flagellar motor components. © 2011 Blackwell Publishing Ltd.

  9. A novel method for simulation of brushless DC motor servo-control system based on MATLAB

    Science.gov (United States)

    Tao, Keyan; Yan, Yingmin

    2006-11-01

    This paper provides a research about the simulation of brush-less DC motor (BLDCM) servo control system. Based on the mathematical model of Brush-less DC motor (BLDCM), built the system simulation model with the MATLAB software. When the system model is made, the isolated functional blocks, such as BLDCM block, the rotor's position detection block, change-phase logic block etc. have been modeled. By the organic combination of these blocks, the model of BLDCM can be established easily. The reasonability and validity have been testified by the simulation results and this novel method offers a new thought way for designing and debugging actual motors.

  10. Design of permanent magnet synchronous motor speed control system based on SVPWM

    Science.gov (United States)

    Wu, Haibo

    2017-04-01

    The control system is designed to realize TMS320F28335 based on the permanent magnet synchronous motor speed control system, and put it to quoting all electric of injection molding machine. The system of the control method used SVPWM, through the sampling motor current and rotating transformer position information, realize speed, current double closed loop control. Through the TMS320F28335 hardware floating-point processing core, realize the application for permanent magnet synchronous motor in the floating point arithmetic, to replace the past fixed-point algorithm, and improve the efficiency of the code.

  11. Stochastic Resonance of Single (Independent of Each Other) Protein Motor System with Fluctuating Potential Barrier

    Institute of Scientific and Technical Information of China (English)

    MA Song-Hua; LI Jing-Hui; JIANG Yong-Qing; FANG Jian-Ping

    2008-01-01

    A single (independent of each other) protein motor system with fluctuating potential barrier and subject to sine electric field is investigated. We first derive the approximate Langevin equation of this system with fluctuating potential barrier. Then from this approximate Langevin equation, we calculate the signal-to-noise ratio (SNR) in the adiabatic limit. The phenomenon of stochastic resonance is found for this protein motor system with fluctuating potential barrier.

  12. The role of the motor system in discriminating normal and degraded speech sounds.

    Science.gov (United States)

    D'Ausilio, Alessandro; Bufalari, Ilaria; Salmas, Paola; Fadiga, Luciano

    2012-07-01

    Listening to speech recruits a network of fronto-temporo-parietal cortical areas. Classical models consider anterior, motor, sites involved in speech production whereas posterior sites involved in comprehension. This functional segregation is more and more challenged by action-perception theories suggesting that brain circuits for speech articulation and speech perception are functionally interdependent. Recent studies report that speech listening elicits motor activities analogous to production. However, the motor system could be crucially recruited only under certain conditions that make speech discrimination hard. Here, by using event-related double-pulse transcranial magnetic stimulation (TMS) on lips and tongue motor areas, we show data suggesting that the motor system may play a role in noisy, but crucially not in noise-free environments, for the discrimination of speech signals. Copyright © 2011 Elsevier Srl. All rights reserved.

  13. Perinatal Development of the Motor Systems Involved in Postural Control

    Directory of Open Access Journals (Sweden)

    Laurent Vinay

    2005-01-01

    Full Text Available Motor behaviors of some species, such as the rat and the human baby, are quite immature at birth. Here we review recent data on some of the mechanisms underlying the postnatal maturation of posture in the rat, in particular the development of pathways descending from the brain stem and projecting onto the lumbar enlargement of the spinal cord. A short-lasting depletion in serotonin affects both posture and the excitability of motoneurons. Here we try to extrapolate to human development and suggest that the abnormalities in motor control observed in childhood—e.g, deficits in motor coordination—might have their roots in the prenatal period, in particular serotonin depletion due to exposure to several environmental and toxicological factors during pregnancy.

  14. Perinatal development of the motor systems involved in postural control.

    Science.gov (United States)

    Vinay, Laurent; Ben-Mabrouk, Faïza; Brocard, Frédéric; Clarac, François; Jean-Xavier, Céline; Pearlstein, Edouard; Pflieger, Jean-François

    2005-01-01

    Motor behaviors of some species, such as the rat and the human baby, are quite immature at birth. Here we review recent data on some of the mechanisms underlying the postnatal maturation of posture in the rat, in particular the development of pathways descending from the brain stem and projecting onto the lumbar enlargement of the spinal cord. A short-lasting depletion in serotonin affects both posture and the excitability of motoneurons. Here we try to extrapolate to human development and suggest that the abnormalities in motor control observed in childhood--e.g. deficits in motor coordination--might have their roots in the prenatal period, in particular serotonin depletion due to exposure to several environmental and toxicological factors during pregnancy.

  15. Control System of Sensorless Brushless DC Motor Based on TMS320F240

    Directory of Open Access Journals (Sweden)

    Li Zeng

    2011-11-01

    Full Text Available A brushless DC(BLDC motor with the characteristics of high speed and high power density has been more widely used in industrial area. The BLDC motor requires the position and speed sensors for control. However the position sensors are undesirable from standpoints of size, cost, maintenance and reliability. There are some different ways that can solve this problem, depending on the flux distribution. This paper describes a control system of sensorless BLDC motor. The back-EMF is adopted to detect the rotor position. The back-EMF is very small in the motor starting process, and it is difficult to obtain rotor position efficiently. A re-setting method of the rotor is proposed in the paper, and current closed loop is used for high-speed and safety in the motor starting process. A good speed and current double closed loops system is designed. The speed and current regulators are implemented by a digital signal processor(DSP. A simple algorithm is used to calculate motor speed indirectly by the software, which simplifies the system hardware structure. The hardware structure and software design of sensorless BLDC motor control system are described in details. The simulation and experimental results have shown the validity of the sensorless control system and the accuracy of the detective position signal obtained.

  16. Changes in corticospinal excitability during consolidation predict acute exercise-induced off-line gains in procedural memory

    DEFF Research Database (Denmark)

    Ostadan, Fatemeh; Centeno, Carla; Daloze, Jean-Felix

    2016-01-01

    A single bout of cardiovascular exercise performed immediately after practicing a motor task improves the long-term retention of the skill through an optimization of memory consolidation. However, the specific brain mechanisms underlying the effects of acute cardiovascular exercise on procedural...... in the exercise condition showed larger (∼24%) improvements in procedural memory through consolidation although differences between groups did not reach statistical significance. Exercise promoted an increase in CSE, which remained elevated 2h after exercise. More importantly, global increases in CSE following...... memory are poorly understood. We sought to determine if a single bout of exercise modifies corticospinal excitability (CSE) during the early stages of memory consolidation. In addition, we investigated if changes in CSE are associated with exercise-induced off-line gains in procedural memory...

  17. From the Kinetic Energy Recovery System to the Thermo-Hydraulic Hybrid Motor Vehicle

    Science.gov (United States)

    Cristescu, Corneliu; Drumea, Petrin; Guta, Dragos; Dumitrescu, Catalin

    2011-12-01

    The paper presents some theoretical and experimental results obtained by the Hydraulics and Pneumatics Research Institute INOE 2000-IHP with its partners, regarding the creating of one hydraulic system able to recovering the kinetic energy of the motor vehicles, in the braking phases, and use this recovered energy in the starting and accelerating phases. Also, in the article is presented a testing stand, which was especially designed for testing the hydraulic system for recovery the kinetic energy. Through mounting of the kinetic energy recovering hydraulic system, on one motor vehicle, this vehicle became a thermo-hydraulic hybrid vehicle. Therefore, the dynamic behavior was analyzed for the whole hybrid motor vehicle, which includes the energy recovery system. The theoretical and experimental results demonstrate the possible performances of the hybrid vehicle and that the kinetic energy recovery hydraulic systems are good means to increase energy efficiency of the road motor vehicles and to decrease of the fuel consumption.

  18. Fully Automated Detection of Corticospinal Tract Damage in Chronic Stroke Patients

    Directory of Open Access Journals (Sweden)

    Ming Yang

    2014-01-01

    Full Text Available Structural integrity of the corticospinal tract (CST after stroke is closely linked to the degree of motor impairment. However, current methods for measurement of fractional atrophy (FA of CST based on region of interest (ROI are time-consuming and open to bias. Here, we used tract-based spatial statistics (TBSS together with a CST template with healthy volunteers to quantify structural integrity of CST automatically. Two groups of patients after ischemic stroke were enrolled, group 1 (10 patients, 7 men, and Fugl-Meyer assessment (FMA scores ⩽ 50 and group 2 (12 patients, 12 men, and FMA scores = 100. CST of FAipsi, FAcontra, and FAratio was compared between the two groups. Relative to group 2, FA was decreased in group 1 in the ipsilesional CST (P<0.01, as well as the FAratio (P<0.01. There was no significant difference between the two subgroups in the contralesional CST (P=0.23. Compared with contralesional CST, FA of ipsilesional CST decreased in group 1 (P<0.01. These results suggest that the automated method used in our study could detect a surrogate biomarker to quantify the CST after stroke, which would facilitate implementation of clinical practice.

  19. MRI of the intracranial corticospinal tracts in amyotrophic and primary lateral sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Peretti-Viton, P.; Brunel, H.; Daniel, C.; Salazard, B.; Salamon, G. [Dept. of Neuroradiology, Hopital de la Timone, Marseille (France); Azulay, J.P.; Trefouret, S.; Pouget, J.; Serratrice, G. [Dept. of Neurology and Neuromuscular Diseases, Hopital de la Timone, Marseille (France); Viton, J.M. [Dept. of Physical Medicine and Rehabilitation, Hopital de la Timone, Marseille (France); Flori, A. [Medical Informatics Dept., Hopital Nord, Marseille (France)

    1999-10-01

    Our aim was to investigate the corticospinal tracts (CST) in motor neurone disease, using MRI, and to correlate findings with clinical data. We studied 31 patients with amyotrophic (ALS) and eight with primary lateral sclerosis (PLS). The signal from the CST was classified into four grades on T2-weighted images, and compared to T2-weighted images of 37 age-matched control subjects. No abnormalities were seen in the CST on T1-weighted images and were rarely evident on proton-density weighting. Variable high signal in the CST was found on T2-weighted images in 35 patients, and in 29 control subjects. Our grades 0 and 1 were more frequent in control subjects, grades 2 and 3 more frequent in patients. We found no correlation between the high signal and clinical data, including the duration of the illness. We therefore conclude that this technique is neither sensitive nor specific except in grade 3 which is quite specific for ALS. In half the patients we found atrophy of the superior parietal gyrus, which merits further study. (orig.)

  20. Facilitation of corticospinal tract excitability by transcranial direct current stimulation combined with voluntary grip exercise.

    Science.gov (United States)

    Kim, Gi-Wook; Ko, Myoung-Hwan

    2013-08-26

    Previous studies have established that transcranial direct current stimulation (tDCS) is a powerful technique for the deliberate manipulation of the activity of human cerebral cortex. Moreover, it has also been shown that the non-exhausted voluntary motor exercise increases the excitability of corticospinal tract. We conducted this study to define the facilitation effect following anodal tDCS combined with the voluntary grip exercise as compared with single use of tDCS or voluntary grip exercise. Our result showed that the combination of anodal tDCS with voluntary grip exercise produced a 2-fold increase in the amplitude of MEP as compared with single use of anodal tDCS or voluntary grip exercise. In conclusion, our result could indicate that the treatment outcomes of brain and neurorehabilitation using tDCS would be better when tDCS is combined with the appropriate method of voluntary exercise as compared with single use of tDCS. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Structural damage to the corticospinal tract correlates with bilateral sensorimotor cortex reorganization in stroke patients.

    Science.gov (United States)

    Schaechter, Judith D; Perdue, Katherine L; Wang, Ruopeng

    2008-02-01

    Damage to the corticospinal tract (CST) in stroke patients has been associated with functional reorganization in the ipsilesional and contralesional sensorimotor cortices. However, it is unknown whether a quantitative relationship exists between the extent of structural damage to the CST and functional reorganization in stroke patients. The purpose of the current study was to examine the relationship between structural CST damage and motor task-related cortical activity in chronic hemiparetic stroke patients. In 10 chronic hemiparetic stroke patients with heterogeneous lesions, CST damage was quantified using conventional structural magnetic resonance imaging and tractography based on diffusion tensor imaging. Cortical activity was measured using functional magnetic resonance imaging during repetitive flexion/extension movements of the digits. We found that the two measures of CST damage were strongly correlated. Moreover, greater CST damage was significantly and linearly correlated with increased activation during affected hand movement in the hand area of the contralesional primary sensorimotor cortex (M1/S1) and in the ipsilesional M1/S1 ventral to the hand area. To our knowledge, this is the first demonstration of a quantitative relationship between the extent of structural damage to the CST and functional reorganization in stroke patients. This relationship was observed in stroke patients with heterogeneous lesions, suggesting that CST damage is a factor relevant to the variation in functional reorganization in the clinical population.

  2. Optimization of the transcranial magnetic stimulation protocol by defining a reliable estimate for corticospinal excitability.

    Directory of Open Access Journals (Sweden)

    Koen Cuypers

    Full Text Available The goal of this study was to optimize the transcranial magnetic stimulation (TMS protocol for acquiring a reliable estimate of corticospinal excitability (CSE using single-pulse TMS. Moreover, the minimal number of stimuli required to obtain a reliable estimate of CSE was investigated. In addition, the effect of two frequently used stimulation intensities [110% relative to the resting motor threshold (rMT and 120% rMT] and gender was evaluated. Thirty-six healthy young subjects (18 males and 18 females participated in a double-blind crossover procedure. They received 2 blocks of 40 consecutive TMS stimuli at either 110% rMT or 120% rMT in a randomized order. Based upon our data, we advise that at least 30 consecutive stimuli are required to obtain the most reliable estimate for CSE. Stimulation intensity and gender had no significant influence on CSE estimation. In addition, our results revealed that for subjects with a higher rMT, fewer consecutive stimuli were required to reach a stable estimate of CSE. The current findings can be used to optimize the design of similar TMS experiments.

  3. Optimization of the transcranial magnetic stimulation protocol by defining a reliable estimate for corticospinal excitability.

    Science.gov (United States)

    Cuypers, Koen; Thijs, Herbert; Meesen, Raf L J

    2014-01-01

    The goal of this study was to optimize the transcranial magnetic stimulation (TMS) protocol for acquiring a reliable estimate of corticospinal excitability (CSE) using single-pulse TMS. Moreover, the minimal number of stimuli required to obtain a reliable estimate of CSE was investigated. In addition, the effect of two frequently used stimulation intensities [110% relative to the resting motor threshold (rMT) and 120% rMT] and gender was evaluated. Thirty-six healthy young subjects (18 males and 18 females) participated in a double-blind crossover procedure. They received 2 blocks of 40 consecutive TMS stimuli at either 110% rMT or 120% rMT in a randomized order. Based upon our data, we advise that at least 30 consecutive stimuli are required to obtain the most reliable estimate for CSE. Stimulation intensity and gender had no significant influence on CSE estimation. In addition, our results revealed that for subjects with a higher rMT, fewer consecutive stimuli were required to reach a stable estimate of CSE. The current findings can be used to optimize the design of similar TMS experiments.

  4. Using TMS to study the role of the articulatory motor system in speech perception.

    Science.gov (United States)

    Möttönen, Riikka; Watkins, Kate E

    2012-09-01

    Background: The ability to communicate using speech is a remarkable skill, which requires precise coordination of articulatory movements and decoding of complex acoustic signals. According to the traditional view, speech production and perception rely on motor and auditory brain areas, respectively. However, there is growing evidence that auditory-motor circuits support both speech production and perception.Aims: In this article we provide a review of how transcranial magnetic stimulation (TMS) has been used to investigate the excitability of the motor system during listening to speech and the contribution of the motor system to performance in various speech perception tasks. We also discuss how TMS can be used in combination with brain-imaging techniques to study interactions between motor and auditory systems during speech perception.Main contribution: TMS has proven to be a powerful tool to investigate the role of the articulatory motor system in speech perception.Conclusions: TMS studies have provided support for the view that the motor structures that control the movements of the articulators contribute not only to speech production but also to speech perception.

  5. Grasping synergies: A motor-control approach to the mirror neuron mechanism

    Science.gov (United States)

    D'Ausilio, Alessandro; Bartoli, Eleonora; Maffongelli, Laura

    2015-03-01

    The discovery of mirror neurons revived interest in motor theories of perception, fostering a number of new studies as well as controversies. In particular, the degree of motor specificity with which others' actions are simulated is highly debated. Human corticospinal excitability studies support the conjecture that a mirror mechanism encodes object-directed goals or low-level kinematic features of others' reaching and grasping actions. These interpretations lead to different experimental predictions and implications for the functional role of the simulation of others' actions. We propose that the representational granularity of the mirror mechanism cannot be any different from that of the motor system during action execution. Hence, drawing from motor control models, we propose that the building blocks of the mirror mechanism are the relatively few motor synergies explaining the variety of hand functions. The recognition of these synergies, from action observation, can be potentially very robust to visual noise and thus demonstrate a clear advantage of using motor knowledge for classifying others' action.

  6. Grasping synergies: a motor-control approach to the mirror neuron mechanism.

    Science.gov (United States)

    D'Ausilio, Alessandro; Bartoli, Eleonora; Maffongelli, Laura

    2015-03-01

    The discovery of mirror neurons revived interest in motor theories of perception, fostering a number of new studies as well as controversies. In particular, the degree of motor specificity with which others' actions are simulated is highly debated. Human corticospinal excitability studies support the conjecture that a mirror mechanism encodes object-directed goals or low-level kinematic features of others' reaching and grasping actions. These interpretations lead to different experimental predictions and implications for the functional role of the simulation of others' actions. We propose that the representational granularity of the mirror mechanism cannot be any different from that of the motor system during action execution. Hence, drawing from motor control models, we propose that the building blocks of the mirror mechanism are the relatively few motor synergies explaining the variety of hand functions. The recognition of these synergies, from action observation, can be potentially very robust to visual noise and thus demonstrate a clear advantage of using motor knowledge for classifying others' action.

  7. Mathematical modeling and dynamic simulation of a class of drive systems with permanent magnet synchronous motors

    Directory of Open Access Journals (Sweden)

    Mikhov M.

    2009-12-01

    Full Text Available The performance of a two-coordinate drive system with permanent magnet synchronous motors is analyzed and discussed in this paper. Both motors have been controlled in brushless DC motor mode in accordance with the rotor positions. Detailed study has been carried out by means of mathematical modeling and computer simulation for the respective transient and steady-state regimes at various load and work conditions. The research carried out as well as the results obtained can be used in the design, optimization and tuning of such types of drive systems. They could be also applied in the teaching process.

  8. Transitioning to Low-GWP Alternatives in Motor Vehicle Air Conditioning Systems

    Science.gov (United States)

    This fact sheet provides information on low-GWP alternatives in newly manufactured motor vehicle air conditioning systems. It discusses HFC alternatives, market trends, challenges to market entry for alternatives, and potential solutions.

  9. United States industrial electric motor systems market opportunities assessment: Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1998-12-01

    The Market Assessment is designed to be of value to manufacturers, distributors, engineers, and others in the supply channels for motor systems. It provides a detailed and highly differentiated portrait of their end-use markets.

  10. [Glutamatergic neurotransmitter system in regulation of the gastrointestinal tract motor activity].

    Science.gov (United States)

    Alekseeva, E V; Popova, T S; Sal'nikov, P S

    2015-01-01

    The review include actual facts, demonstrating high probability of glutamatergic neurotransmitter system role in the regulation of the gastrointestinal tract motor activity. These facts suggest significant role of the glutamatergic neurotransmitter system dysfunction in forming motor activity disorders of the digestive tract, including in patients in critical condition. The analysis is based on results of multiple experimental and clinical researches of glutamic acid and other components of the glutamatergic neurotransmitter system in central nervous system and autonomic nervous system (with the accent on the enteral nervous system) in normal conditions and with functioning changes of the glutamatergic neurotransmitter system in case of inflammation, hupoxia, stress and in critical condition.

  11. The motor evoked potential in aids and HAM/TSP State of the evidence El potencial evocado motor en SIDA y HAM/PET

    Directory of Open Access Journals (Sweden)

    Fidias E. Leon-Sarmiento

    2009-12-01

    Full Text Available OBJECTIVE: We aimed to better understand the involvement of the corticospinal tract, assessed by non-invasive transcranial stimulation, in order to determine the actual involvement of the motor system in patients with HAM/TSP and AIDS. METHOD: An exhaustive MEDLINE search for the period of 1985 to 2008 for all articles cross-referenced for "HTLV-I, HTLV-II, HTLV-III and HIV, HIV1, HIV2, evoked potential, motor evoked potential, high voltage electrical stimulation, transcranial magnetic stimulation, magnetic stimulation, corticomotor physiology, motor pathways, acquired immunodeficiency syndrome, AIDS, SIDA, tropical spastic paraparesis, HTLV-I-associated myelopathy, HAM, TSP, and HAM/TSP" were selected and analysed. RESULTS: Eighteen papers published in English, Spanish, Portuguese, French and Japanese were identified. Only the central motor conduction time has been analyzed in seropositive patients to human retroviruses. The investigations done on HAM/TSP support the involvement of the pyramidal tract mainly at lower levels, following a centripetal pattern; in AIDS, such an involvement seems to be more prominent at brain levels following a centrifugal pattern. CONCLUSION: The central motor conduction time abnormalities and involvement differences of the corticospinal tract of patients with AIDS and HAM/TSP dissected here would allow to re-orient early neurorehabilitation measures in these retroviruses-associated neurodegenerative disorders. Besides this, more sophisticated and sensitive non-invasive corticospinal stimulation measures that detect early changes in thalamocortical-basal ganglia circuitry will be needed in both clinically established as well as asymptomatic patients at times when the fastest corticospinal fibers remain uninvolved.OBJETIVO: Investigar el compromiso del tracto piramidal, evaluado por estimulación trascranial no invasiva, en pacientes afectados por SIDA y HAM/TSP. MÉTODO: Se realizó una búsqueda en la base de

  12. An Active Stereo Vision System Based on Neural Pathways of Human Binocular Motor System

    Institute of Scientific and Technical Information of China (English)

    Yu-zhang Gu; Makoto Sato; Xiao-lin Zhang

    2007-01-01

    An active stereo vision system based on a model of neural pathways of human binocular motor system is proposed. With this model, it is guaranteed that the two cameras of the active stereo vision system can keep their lines of sight fixed on the same target object during smooth pursuit. This feature is very important for active stereo vision systems, since not only 3D reconstruction needs the two cameras have an overlapping field of vision, but also it can facilitate the 3D reconstruction algorithm. To evaluate the effectiveness of the proposed method, some software simulations are done to demonstrate the same target tracking characteristic in a virtual environment apt to mistracking easily. Here, mistracking means two eyes track two different objects separately. Then the proposed method is implemented in our active stereo vision system to perform real tracking task in a laboratory scene where several persons walk self-determining. Before the proposed model is implemented in the system, mistracking occurred frequently. After it is enabled, mistracking never occurred. The result shows that the vision system based on neural pathways of human binocular motor system can reliably avoid mistracking.

  13. The Functional Integration in the Sensory-Motor System Predicts Aging in Healthy Older Adults

    OpenAIRE

    He, Hui; Luo, Cheng; Chang, Xin; Shan, Yan; Cao, Weifang; Gong, Jinnan; Klugah-Brown, Benjamin; Bobes, Maria A.; Biswal, Bharat; Yao, Dezhong

    2017-01-01

    Healthy aging is typically accompanied by a decrease in the motor capacity. Although the disrupted neural representations and performance of movement have been observed in older age in previous studies, the relationship between the functional integration of sensory-motor (SM) system and aging could be further investigated. In this study, we examine the impact of healthy aging on the resting-state functional connectivity (rsFC) of the SM system, and investigate as to how aging is affecting the...

  14. Finite-Time Chaos Control of a Complex Permanent Magnet Synchronous Motor System

    Directory of Open Access Journals (Sweden)

    Xiaobing Zhou

    2014-01-01

    Full Text Available This paper investigates the finite-time chaos control of a permanent magnet synchronous motor system with complex variables. Based on the finite-time stability theory, two control strategies are proposed to realize stabilization of the complex permanent magnet synchronous motor system in a finite time. Two numerical simulations have been conducted to demonstrate the validity and feasibility of the theoretical analysis.

  15. Corticospinal excitability measurements using transcranial magnetic stimulation are valid with intramuscular electromyography

    Science.gov (United States)

    2017-01-01

    Objectives Muscular targets that are deep or inaccessible to surface electromyography (sEMG) require intrinsic recording using fine-wire electromyography (fEMG). It is unknown if fEMG validly record cortically evoked muscle responses compared to sEMG. The purpose of this investigation was to establish the validity and agreement of fEMG compared to sEMG to quantify typical transcranial magnetic stimulation (TMS) measures pre and post repetitive TMS (rTMS). The hypotheses were that fEMG would demonstrate excellent validity and agreement compared with sEMG. Materials and methods In ten healthy volunteers, paired pulse and cortical silent period (CSP) TMS measures were collected before and after 1200 pulses of 1Hz rTMS to the motor cortex. Data were simultaneously recorded with sEMG and fEMG in the first dorsal interosseous. Concurrent validity (r and rho) and agreement (Tukey mean-difference) were calculated. Results fEMG quantified corticospinal excitability with good to excellent validity compared to sEMG data at both pretest (r = 0.77–0.97) and posttest (r = 0.83–0.92). Pairwise comparisons indicated no difference between sEMG and fEMG for all outcomes; however, Tukey mean-difference plots display increased variance and questionable agreement for paired pulse outcomes. CSP displayed the highest estimates of validity and agreement. Paired pulse MEP responses recorded with fEMG displayed reduced validity, agreement and less sensitivity to changes in MEP amplitude compared to sEMG. Change scores following rTMS were not significantly different between sEMG and fEMG. Conclusion fEMG electrodes are a valid means to measure CSP and paired pulse MEP responses. CSP displays the highest validity estimates, while caution is warranted when assessing paired pulse responses with fEMG. Corticospinal excitability and neuromodulatory aftereffects from rTMS may be assessed using fEMG. PMID:28231250

  16. Filtering and Control of High Speed Motor Current in a Flywheel Energy Storage System

    Science.gov (United States)

    Kenny, Barbara H.; Santiago, Walter

    2004-01-01

    The NASA Glenn Research Center has been developing technology to enable the use of high speed flywheel energy storage units in future spacecraft for the last several years. An integral part of the flywheel unit is the three phase motor/generator that is used to accelerate and decelerate the flywheel. The motor/generator voltage is supplied from a pulse width modulated (PWM) inverter operating from a fixed DC voltage supply. The motor current is regulated through a closed loop current control that commands the necessary voltage from the inverter to achieve the desired current. The current regulation loop is the innermost control loop of the overall flywheel system and, as a result, must be fast and accurate over the entire operating speed range (20,000 to 60,000 rpm) of the flywheel. The voltage applied to the motor is a high frequency PWM version of the DC bus voltage that results in the commanded fundamental value plus higher order harmonics. Most of the harmonic content is at the switching frequency and above. The higher order harmonics cause a rapid change in voltage to be applied to the motor that can result in large voltage stresses across the motor windings. In addition, the high frequency content in the motor causes sensor noise in the magnetic bearings that leads to disturbances for the bearing control. To alleviate these problems, a filter is used to present a more sinusoidal voltage to the motor/generator. However, the filter adds additional dynamics and phase lag to the motor system that can interfere with the performance of the current regulator. This paper will discuss the tuning methodology and results for the motor/generator current regulator and the impact of the filter on the control. Results at speeds up to 50,000 rpm are presented.

  17. Mental imagery of speech: linking motor and perceptual systems through internal simulation and estimation

    Directory of Open Access Journals (Sweden)

    Xing eTian

    2012-11-01

    Full Text Available The neural basis of mental imagery has been investigated by localizing the underlying neural networks, mostly in motor and perceptual systems, separately. However, how modality-specific representations are top-down induced and how the action and perception systems interact in the context of mental imagery is not well understood. Imagined speech production (‘articulation imagery’, which induces the kinesthetic feeling of articulator movement and its auditory consequences, provides a new angle because of the concurrent involvement of motor and perceptual systems. On the basis of previous findings in mental imagery of speech, we argue for the following regarding the induction mechanisms of mental imagery and the interaction between motor and perceptual systems: (1 Two distinct top-down mechanisms, memory retrieval and motor simulation, exist to induce estimation in perceptual systems. (2 Motor simulation is sufficient to internally induce the representation of perceptual changes that would be caused by actual movement (perceptual associations; however, this simulation process only has modulatory effects on the perception of external stimuli, which critically depends on context and task demands. Considering the proposed simulation-estimation processes as common mechanisms for interaction between motor and perceptual systems, we outline how mental imagery (of speech relates to perception and production, and how these hypothesized mechanisms might underpin certain neural disorders.

  18. Diffusion tensor imaging detects Wallerian degeneration of the corticospinal tract early after cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Ruiman Xie; Min Fang; Linjiang Zhou; Shanghua Fan; Jianying Liu; Hongbo Quan; Man Luo; Dongying Qiu

    2012-01-01

    To investigate the feasibility and time window of early detection of Wallerian degeneration in the corticospinal tract after middle cerebral artery infarction, 23 patients were assessed using magnetic resonance diffusion tensor imaging at 3.0T within 14 days after the infarction. The fractional anisotropy values of the affected corticospinal tract began to decrease at 3 days after onset and decreased in all cases at 7 days. The diffusion coefficient remained unchanged. Experimental findings indicate that diffusion tensor imaging can detect the changes associated with Wallerian degeneration of the corticospinal tract as early as 3 days after cerebral infarction.

  19. Magnetic suspension motorized spindle-cutting system dynamics analysis and vibration control review

    Directory of Open Access Journals (Sweden)

    Xiaoli QIAO

    2016-10-01

    Full Text Available The performance of high-speed spindle directly determines the development of high-end machine tools. The cutting system's dynamic characteristics and vibration control effect are inseparable with the performance of the spindle,which influence each other, synergistic effect together the cutting efficiency, the surface quality of the workpiece and tool life in machining process. So, the review status on magnetic suspension motorized spindle, magnetic suspension bearing-flexible rotor system dynamics modeling theory and status of active control technology of flexible magnetic suspension motorized spindle rotor vibration are studied, and the problems which present in the magnetic suspension flexible motorized spindle rotor systems are refined, and the development trend of magnetic levitation motorized spindle and the application prospect is forecasted.

  20. Fuzzy Logic Based Speed Control System for ThreePhase Induction Motor

    Directory of Open Access Journals (Sweden)

    Marwan A. Badran

    2013-05-01

    Full Text Available Three-phase induction motors have been used in a wide range of industry applications. Using modern technology, the speed of induction motor can be easily controlled by variable frequency drives (VFDs. These drives use high speed power transistors with various switching techniques, mainly PWM schemes. For several decades, conventional control systems were applied to electric drives to control the speed of induction motor. Although conventional controllers showed good results, but they still need tuning to obtain optimum results. The recent proposed control systems use fuzzy logic controller (FLC to enhance the performance of induction motor drives. In this paper, a fuzzy logic based speed control system is presented. The proposed controller has been designed with MATLAB/SIMULINK software, and it was tested for various operating conditions including load disturbance and sudden change of reference speed. The results showed better performance of the proposed controller compared with the conventional PI controller.

  1. Prognostic value of cortically induced motor evoked activity by TMS in chronic stroke: Caveats from a revealing single clinical case

    Directory of Open Access Journals (Sweden)

    Amengual Julià L

    2012-06-01

    Full Text Available Abstract Background We report the case of a chronic stroke patient (62 months after injury showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand. Case presentation Multimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP, and Cortical Silent period (CSP as well as functional magnetic resonance imaging (fMRI of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI Tractography of corticospinal tract (CST. Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG activity (indexed by CSP demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations. Conclusions The potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.

  2. Prognostic Value of Cortically Induced Motor Evoked Activity by TMS in Chronic Stroke: Caveats from a Revealing Single Clinical Case

    LENUS (Irish Health Repository)

    Amengual, Julià L

    2012-06-08

    AbstractBackgroundWe report the case of a chronic stroke patient (62 months after injury) showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS) of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand.Case presentationMultimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP), and Cortical Silent period (CSP) as well as functional magnetic resonance imaging (fMRI) of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI) Tractography of corticospinal tract (CST). Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG) activity (indexed by CSP) demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations.ConclusionsThe potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.

  3. Evidence against a single coordinate system representation in the motor cortex.

    Science.gov (United States)

    Wu, Wei; Hatsopoulos, Nicholas

    2006-11-01

    Understanding the coordinate systems in which the motor cortical cells encode movement parameters such as direction is a fundamental yet unresolved issue. Although many studies have assumed that motor cortex encodes direction in an extrinsic, Cartesian (CA) coordinate system, other studies have provided evidence for encoding in intermediate coordinate systems such as a shoulder-centered (SC) or in a purely intrinsic, joint-angle-based (JA) coordinate frame. By simultaneously recording from multiple single units in primary motor cortex, we examined movement direction encoding under each of these three coordinate systems. We directly compared the degree of directional tuning invariance over multiple sub-regions in the workspace. We also compared the mutual information between neuronal firing rate and movement direction in the three systems. We observed a broad range of directional invariance in all three coordinate systems with no strong dominance of any single coordinate system. The mutual information analyses corroborated this observation. However, we found a small but significant bias toward the SC coordinate frame, which was also supported by population vector decoding. Similar results were found when we compared hand/torque force direction encoding in all three coordinate systems. These results suggest that the motor cortex employs a coordinate system that is yet to be discovered or perhaps that the motor cortex should not be viewed as a substrate for any coordinate system representation.

  4. Changes in cortico-spinal excitability following uphill versus downhill treadmill exercise.

    Science.gov (United States)

    Garnier, Yoann M; Lepers, Romuald; Stapley, Paul J; Papaxanthis, Charalambos; Paizis, Christos

    2017-01-15

    An acute bout of aerobic exercise induces neuroplasticity in the motor cortex. Moreover, paired associative stimulation (PAS) is known to induce neuroplasticity in M1. However, the possible influence of the type of exercise on the neuroplastic changes remains unknown. The present study investigated the effects of two different modes of muscle contraction produced during locomotor exercise on changes in corticospinal (CS) excitability. Subjects performed two 30-min treadmill exercises at an intensity corresponding to 60% of their maximal heart rate with either a +10% (uphill) or -10% (downhill) slope. These exercises were followed or not by paired associative stimulation method (PAS25) which consisted of 200 paired stimuli (0.25Hz, 15min) of median nerve electrical stimulation followed by transcranial magnetic stimulation of the hand M1 area (ISI 25ms). Motor evoked potentials (MEP), assessed through abductor pollicis brevis (APB) activity were obtained before exercise, at 5min, 15min and 30min after exercise. A significant (P<0.05) increase of the MEP amplitude was observed 30min after both exercises but was not different between the two modes of locomotion. On the contrary, MEP amplitude with PAS25 increased only 30min after downhill exercise. We conclude that sub-maximal treadmill exercise increases CS excitability within a period of 30min. However, the predominant mode of muscle contraction during uphill versus downhill locomotion does not influence CS excitability when assessed using a non-exercised muscle. However, results from PAS25 suggest that specific neuroplastic changes occur likely due to homeostatic mechanisms induced by exercise plus a PAS protocol. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. System for magnetic monitoring of high voltage motors MM6212

    Directory of Open Access Journals (Sweden)

    Kartalović Nenad

    2012-01-01

    Full Text Available This paper suggests the possibility of diagnosing different types of failure in working induction motors using a device for spectral analysis of axial leakage flux, which has been developed by the Electrotechnical Institute Nikola Tesla. A search coil, which can be of different diameters, was mounted concentrically on the shaft at the rear of the motor. The electromotive force (emf on each of the coils, created as a result of weak magnetic field changes, has a low amplitude. Following the necessary amplifications and adjustments, the signal is digitised on acquisition. In the fast Fourier transform (FFT stage, the sampled and quantised digital time-based signal is converted to a frequency spectrum. Changes in spectral content are used to identify developing faults.

  6. A model for improving energy efficiency in industrial motor system using multicriteria analysis

    Energy Technology Data Exchange (ETDEWEB)

    Herrero Sola, Antonio Vanderley, E-mail: sola@utfpr.edu.br [Federal University of Technology, Parana, Brazil (UTFPR)-Campus Ponta Grossa, Av. Monteiro Lobato, Km 4, CEP: 84016-210 (Brazil); Mota, Caroline Maria de Miranda, E-mail: carolmm@ufpe.br [Federal University of Pernambuco, Cx. Postal 7462, CEP 50630-970, Recife (Brazil); Kovaleski, Joao Luiz [Federal University of Technology, Parana, Brazil (UTFPR)-Campus Ponta Grossa, Av. Monteiro Lobato, Km 4, CEP: 84016-210 (Brazil)

    2011-06-15

    In the last years, several policies have been proposed by governments and global institutions in order to improve the efficient use of energy in industries worldwide. However, projects in industrial motor systems require new approach, mainly in decision making area, considering the organizational barriers for energy efficiency. Despite the wide application, multicriteria methods remain unexplored in industrial motor systems until now. This paper proposes a multicriteria model using the PROMETHEE II method, with the aim of ranking alternatives for induction motors replacement. A comparative analysis of the model, applied to a Brazilian industry, has shown that multicriteria analysis presents better performance on energy saving as well as return on investments than single criterion. The paper strongly recommends the dissemination of multicriteria decision aiding as a policy to support the decision makers in industries and to improve energy efficiency in electric motor systems. - Highlights: > Lack of decision model in industrial motor system is the main motivation of the research. > A multicriteria model based on PROMETHEE method is proposed with the aim of supporting the decision makers in industries. > The model can contribute to transpose some barriers within the industries, improving the energy efficiency in industrial motor system.

  7. The cortical motor system of the marmoset monkey (Callithrix jacchus).

    Science.gov (United States)

    Bakola, Sophia; Burman, Kathleen J; Rosa, Marcello G P

    2015-04-01

    Precise descriptions of the anatomical pathways that link different areas of the cerebral cortex are essential to the understanding of the sensorimotor and association processes that underlie human actions, and their impairment in pathological situations. Many years of research in macaque monkeys have critically shaped how we currently think about cortical motor function in humans. However, it is important to obtain additional understanding about the homologies between cortical areas in human and various non-human primates, and in particular how evolutionary changes in connectivity within specific neural circuits impact on the capacity for different behaviors. Current research has converged on the New World marmoset monkey as an important animal model for cortical function and dysfunction, emphasizing advantages unique to this species. However, the motor repertoire of the marmoset differs from that of the macaque in many ways, including the capacity for skilled use of the hands. Here, we review current knowledge about the cortical frontal areas in marmosets, which are key to the generation and control of motor behaviors, with focus on comparative analyses. We note significant parallels with the macaque monkey, as well as a few potentially important differences, which suggest future directions for work involving architectonic and functional analyses.

  8. Sensorless Monitoring of a Motor-Drive Machanical System Based on Adaptive Signal Decomposition

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-feng; JIAO Li-cheng

    2006-01-01

    A method for estimating current harmonics of an induction motor is introduced which is used for sensorless monitoring of a mechanical system driven by the motor. The method is based on an adaptive signal representation and is proposed to extract weak harmonics from a noisy current signal, especially in the presence of additive interference caused by transient modulation waves. As an application, a rotor unbalance experiment of rotating machinery driven by an induction motor is carried out. The result shows that the eccentricity harmonic magnitude of a current signal obtained by the method represents the rotor unbalance conditions sensitively. Vibration analysis is used to validate the proposed method.

  9. A single bout of high-intensity interval training improves motor skill retention in individuals with stroke

    DEFF Research Database (Denmark)

    Nepveu, Jean-Francois; Thiel, Alexander; Tang, Ada

    2017-01-01

    intensity is sufficient to induce neuroplastic changes and improve motor skill retention in patients with chronic stroke. METHODS: Twenty-two patients with different levels of motor impairment were recruited. On the first session, the effects of a maximal graded exercise test on corticospinal...... exercise test triggers only modest neuroplastic changes in patients with chronic stroke. However, a single bout of high-intensity interval training performed immediately after motor practice improves skill retention, which could potentially accelerate motor recovery in these individuals....

  10. Corticospinal contribution to arm muscle activity during human walking

    DEFF Research Database (Denmark)

    Barthélemy, Dorothy; Nielsen, Jens Bo

    2010-01-01

    potentials (MEPs) elicited in the posterior deltoid muscle (PD) by transcranial magnetic stimulation (TMS) were modulated during the gait cycle in parallel with changes in the background EMG activity. There was no significant difference in the size of the MEPs at a comparable level of background EMG during...... walking and during static PD contraction. Short latency intracortical inhibition (SICI; 2 ms interval) studied by paired-pulse TMS was diminished during bursts of PD EMG activity. This could not be explained only by changes in background EMG activity and/or control MEP size, since SICI showed...... no correlation to the level of background EMG activity during static PD contraction. Finally, TMS at intensity below the threshold for activation of corticospinal tract fibres elicited a suppression of the PD EMG activity during walking. Since TMS at this intensity is likely to only activate intracortical...

  11. Speed and Displacement Control System of Bearingless Brushless DC Motor Based on Improved Bacterial Foraging Algorithm

    Directory of Open Access Journals (Sweden)

    Diao Xiaoyan

    2016-01-01

    Full Text Available To solve the deficiencies of long optimization time and poor precision existing in conventional bacterial foraging algorithm (BFA in the process of parameter optimization, an improved bacterial foraging algorithm (IBFA is proposed and applied to speed and displacement control system of bearingless brushless DC (Bearingless BLDC motors. To begin with the fundamental principle of BFA, the proposed method is introduced and the individual intelligence is efficiently used in the process of parameter optimization, and then the working principle of bearingless BLDC motors is expounded. Finally, modeling and simulation of the speed and displacement control system of bearingless BLDC motors based on the IBFA are carried out by taking the software of MATLAB/Simulink as a platform. Simulation results show that, speed overshoot, torque ripple and rotor position oscillation are dramatically reduced, thus the proposed method has good application prospects in the field of bearingless motors.

  12. Modeling of R/C Servo Motor and Application to Underactuated Mechanical Systems

    Science.gov (United States)

    Ishikawa, Masato; Kitayoshi, Ryohei; Wada, Takashi; Maruta, Ichiro; Sugie, Toshiharu

    An R/C servo motor is a compact package of a DC geard-motor associated with a position servo controller. They are widely used in small-sized robotics and mechatronics by virtue of their compactness, easiness-to-use and high/weight ratio. However, it is crucial to clarify their internal model (including the embedded position servo) in order to improve control performance of mechatronic systems using R/C servo motors, such as biped robots or underactuted sysyems. In this paper, we propose a simple and realistic internal model of the R/C servo motors including the embedded servo controller, and estimate their physical parameters using continuous-time system identification method. We also provide a model of reference-to-torque transfer function so that we can estimate the internal torque acting on the load.

  13. Induction Motor Drive System Based on Linear Active Disturbance Rejection Controller

    Science.gov (United States)

    Liu, Liying; Zhang, Yongli; Yao, Qingmei

    It is difficult to establish an exact mathematical model for the induction motor and the robustness is poor of the vector control system using PI regulator. This paper adopts the linear active disturbance rejection controller (LADRC) to control inductor motor. LADRC doesn't need the exact mathematical model of motor and it can not only estimate but also compensate the general disturbance that includes the coupling items in model of motor and parameters perturbations by linear extended state observer (LESO), so the rotor flux and torque fully decouple. As a result, the performance is improved. To prove the above control scheme, the proposed control system has been simulated in MATLAB/SIMULINK, and the comparison was made with PID. Simulation results show that LADRC' has better performance and robustness than PID.

  14. On-Line Broken-Bar Fault Diagnosis System of Induction Motor

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rong; WANG Xiuhe

    2008-01-01

    Induction motor faults including mechanical and electrical faults are reviewed. The fault diagnosis methods are summarized. To analyze the influence of stator current, torque, speed and rotor current on faulted bars, a time-stepping transient finite element (FE) model of induction motor with bars faulted is created in this paper. With wavelet package analysis method and FFT method, the simulation result of finite element is analyzed. Based on the simulation analysis, the on-line fault diagnosis system of induction motor with bars faulted is developed. With the speed of broken bars motor changed from 1 478 r/min to 1 445 r/min, the FFT power spectra and the wavelet package decoupling factors are given. The comparison result shows that the on-line diagnosis system can detect broken-bar fault efficiently.

  15. Multiple Resonance and Stability of a Motor-elastic Linkage Mechanism System

    Institute of Scientific and Technical Information of China (English)

    LI Zhao-jun; CAI Gan-wei; DAI Wen-zheng

    2006-01-01

    The dynamics of a three-phase AC motor-elastic linkage mechanism system is considered. Taking the drive motor and the linkage mechanism as an integrated system, the coupling dynamic equations of the system are established by the finite element method. The multiple resonance and its stability of the system are studied using the method of multiple scales. The first order approximate solutions of the multiple resonance of the system are obtained. An algorithm for determining the stability of resonance is derived. The studies show that the multiple resonance and its stability of the system are not only related to the structure parameters of the linkage mechanism, but also to the electromagnetism parameters of the motor. At last, an experiment is given to verify the results of the theoretical analysis.

  16. A pilot feasibility study of daily rTMS to modify corticospinal excitability during lower limb immobilization.

    Science.gov (United States)

    Ricci, Raffaella; Ramsey, Dave; Johnson, Kevin; Borckardt, Jeffrey J; Vallejo, Matthew; Roberts, Donna R; George, Mark S

    2008-10-01

    Short term immobilization of the lower limb is associated with increased corticospinal excitability at 24 hours post cast removal. We wondered whether daily stimulation of the motor cortex might decrease brain reorganization during casting. We tested the feasibility of this approach. Using transcranial magnetic stimulation (TMS), resting motor threshold and recruitment curves were obtained at baseline in 6 healthy participants who then had leg casts placed for 10 days. On 7 of the 10 days subjects received 20 minutes of 1 Hz repetitive TMS (rTMS). TMS measures were then recorded immediately after and 24 hours post cast removal. Four of 6 subjects completed the study. At the group level there were no changes in excitability following cast removal. At the individual level, two participants did not show any change, 1 participant had higher and one lower excitability 24 hours after cast removal. Daily rTMS over motor cortex is feasible during casting and may modify neuroplastic changes occurring during limb disuse. A prospective double blind study is warranted to test whether daily rTMS might improve outcome in subjects undergoing casting, and perhaps in other forms of limb disuse such as those following brain injury or weightlessness in space flight.

  17. Changes in corticospinal excitability during consolidation predict acute exercise-induced off-line gains in procedural memory.

    Science.gov (United States)

    Ostadan, Fatemeh; Centeno, Carla; Daloze, Jean-Felix; Frenn, Mira; Lundbye-Jensen, Jesper; Roig, Marc

    2016-12-01

    A single bout of cardiovascular exercise performed immediately after practicing a motor task improves the long-term retention of the skill through an optimization of memory consolidation. However, the specific brain mechanisms underlying the effects of acute cardiovascular exercise on procedural memory are poorly understood. We sought to determine if a single bout of exercise modifies corticospinal excitability (CSE) during the early stages of memory consolidation. In addition, we investigated if changes in CSE are associated with exercise-induced off-line gains in procedural memory. Participants practiced a serial reaction time task followed by either a short bout of acute exercise or a similar rest period. To monitor changes in CSE we used transcranial magnetic stimulation applied to the primary motor cortex (M1) at baseline, 15, 35, 65 and 125min after exercise or rest. Participants in the exercise condition showed larger (∼24%) improvements in procedural memory through consolidation although differences between groups did not reach statistical significance. Exercise promoted an increase in CSE, which remained elevated 2h after exercise. More importantly, global increases in CSE following exercise correlated with the magnitude of off-line gains in skill level assessed in a retention test performed 8h after motor practice. A single bout of exercise modulates short-term neuroplasticity mechanisms subserving consolidation processes that predict off-line gains in procedural memory. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. A dendritic mechanism for decoding traveling waves: principles and applications to motor cortex.

    Directory of Open Access Journals (Sweden)

    Stewart Heitmann

    2013-10-01

    Full Text Available Traveling waves of neuronal oscillations have been observed in many cortical regions, including the motor and sensory cortex. Such waves are often modulated in a task-dependent fashion although their precise functional role remains a matter of debate. Here we conjecture that the cortex can utilize the direction and wavelength of traveling waves to encode information. We present a novel neural mechanism by which such information may be decoded by the spatial arrangement of receptors within the dendritic receptor field. In particular, we show how the density distributions of excitatory and inhibitory receptors can combine to act as a spatial filter of wave patterns. The proposed dendritic mechanism ensures that the neuron selectively responds to specific wave patterns, thus constituting a neural basis of pattern decoding. We validate this proposal in the descending motor system, where we model the large receptor fields of the pyramidal tract neurons - the principle outputs of the motor cortex - decoding motor commands encoded in the direction of traveling wave patterns in motor cortex. We use an existing model of field oscillations in motor cortex to investigate how the topology of the pyramidal cell receptor field acts to tune the cells responses to specific oscillatory wave patterns, even when those patterns are highly degraded. The model replicates key findings of the descending motor system during simple motor tasks, including variable interspike intervals and weak corticospinal coherence. By additionally showing how the nature of the wave patterns can be controlled by modulating the topology of local intra-cortical connections, we hence propose a novel integrated neuronal model of encoding and decoding motor commands.

  19. A new multi-motor drive system based on two-stage direct power converter

    OpenAIRE

    Kumar, Dinesh

    2011-01-01

    The two-stage AC to AC direct power converter is an alternative matrix converter topology, which offers the benefits of sinusoidal input currents and output voltages, bidirectional power flow and controllable input power factor. The absence of any energy storage devices, such as electrolytic capacitors, has increased the potential lifetime of the converter. In this research work, a new multi-motor drive system based on a two-stage direct power converter has been proposed, with two motors c...

  20. Feeding System Analysis of Self-Controlled Inverter-Bed Inductor Motors

    Directory of Open Access Journals (Sweden)

    S. V. Alexandrovsky

    2010-01-01

    Full Text Available The paper analyzes feeding systems for self-controlled inverter-bed inductor motor windings. Peculiar operational feature of the self-controlled inverter-bed inductor motor consists in the fact that the instantaneous electro-magnetic drive is determined by the sum of separate phase moments which are simultaneously alive. Quasi-stationary drive operational modes are analyzed on the basis of the developed simulation model.

  1. System and Method for Determining Rate of Rotation Using Brushless DC Motor

    Science.gov (United States)

    Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    2000-01-01

    A system and method are provided for measuring rate of rotation. A brushless DC motor is rotated and produces a back electromagnetic force (emf) on each winding thereof. Each winding's back-emf is squared. The squared outputs associated with each winding are combined, with the square root being taken of such combination, to produce a DC output proportional only to the rate of rotation of the motor's shaft.

  2. System Identification and Integration Design of an Air/Electric Motor

    Directory of Open Access Journals (Sweden)

    Shih-Yao Huang

    2013-02-01

    Full Text Available This paper presents an integration design and implementation of an air motor and a DC servo motor which utilizes a magnetic powder brake to integrate these two motors together. The dynamic model of the air/electric hybrid system will be derived and eventually leads to successful ECE-40 driving cycle tests with a FPGA-based speed controller. The testing results obtained by using the proposed experimental platform indicate that the total air consumption is about 256 L under air motor mode and the electric charge consumption is about 530 coulombs under DC servo motor mode. In a hybrid mode, the current reduction of the battery is about 18.5%, and then the service life of the battery can be improved. Furthermore, a prototype is built with a proportional-integral (PI speed controller based on a field-programmable gate array (FPGA in order to facilitate the entire analysis of the velocity switch experiment. Through the modular methodology of FPGA, the hybrid power platform can successfully operate under ECE-40 driving cycle with the PI speed controller. The experimental data shows that the chattering ranges of the air motor within ±1 km/h and ±0.2 km/h under DC servo motor drive. Therefore, the PI speed controller based on FPGA is successfully actualized.

  3. Cholinergic systems are essential for late-stage maturation and refinement of motor cortical circuits.

    Science.gov (United States)

    Ramanathan, Dhakshin S; Conner, James M; Anilkumar, Arjun A; Tuszynski, Mark H

    2015-03-01

    Previous studies reported that early postnatal cholinergic lesions severely perturb early cortical development, impairing neuronal cortical migration and the formation of cortical dendrites and synapses. These severe effects of early postnatal cholinergic lesions preclude our ability to understand the contribution of cholinergic systems to the later-stage maturation of topographic cortical representations. To study cholinergic mechanisms contributing to the later maturation of motor cortical circuits, we first characterized the temporal course of cortical motor map development and maturation in rats. In this study, we focused our attention on the maturation of cortical motor representations after postnatal day 25 (PND 25), a time after neuronal migration has been accomplished and cortical volume has reached adult size. We found significant maturation of cortical motor representations after this time, including both an expansion of forelimb representations in motor cortex and a shift from proximal to distal forelimb representations to an extent unexplainable by simple volume enlargement of the neocortex. Specific cholinergic lesions placed at PND 24 impaired enlargement of distal forelimb representations in particular and markedly reduced the ability to learn skilled motor tasks as adults. These results identify a novel and essential role for cholinergic systems in the late refinement and maturation of cortical circuits. Dysfunctions in this system may constitute a mechanism of late-onset neurodevelopmental disorders such as Rett syndrome and schizophrenia.

  4. Synchronous EMG activity in the Piper frequency band reveals the corticospinal demand of walking tasks

    OpenAIRE

    Clark, David J.; Kautz, Steven A.; Bauer, Andrew R.; Chen, Yen-Ting; Evangelos A Christou

    2013-01-01

    Evidence indicates that the frequency-domain characteristics of surface electromyogram (EMG) signals are modulated according to the contributing sources of neural drive. Modulation of inter-muscular EMG synchrony within the Piper frequency band (30–60Hz) during movement tasks has been linked to drive from the corticospinal tract. However, it is not known whether EMG synchrony is sufficiently sensitive to detect task-dependent differences in the corticospinal contribution to leg muscle activat...

  5. 78 FR 66420 - Proposed Enhancements to the Motor Carrier Safety Measurement System (SMS) Public Web Site

    Science.gov (United States)

    2013-11-05

    ... System (SMS) Public Web Site AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION... enhancements to the display of information on the Agency's Safety Measurement System (SMS) public Web site... and Fitness Electronic Records System (SAFER) Web site. Displaying current insurance and authority...

  6. 78 FR 76391 - Proposed Enhancements to the Motor Carrier Safety Measurement System (SMS) Public Web Site

    Science.gov (United States)

    2013-12-17

    ... System (SMS) Public Web Site AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION... Safety Measurement System (SMS) public Web site. On December 6, 2013, Advocates ] for Highway and Auto... Management System Number FMCSA-2013-0392 by any of the following methods: Federal eRulemaking Portal: http...

  7. An investigation of the dynamic electromechanical coupling effects in machine drive systems driven by asynchronous motors

    Science.gov (United States)

    Szolc, Tomasz; Konowrocki, Robert; Michajłow, Maciej; Pręgowska, Agnieszka

    2014-12-01

    In the paper dynamic electromechanical interaction between the rotating machine drive system and the electric driving motor is considered. The investigations are performed by means of the circuit model of the asynchronous motor as well as using an advanced structural hybrid model of the drive system. Using the analytical solutions applied for the electrical and the mechanical systems the electromagnetic stiffness and coefficient of damping, both generated by the electric motor rotationally interacting with the mechanical system of the given dynamic properties, were determined. By means of experimentally validated computational responses obtained for torsional harmonic excitation induced by the driven machine working tool, a modification of dynamic properties of the mechanical system by the electromagnetic flux between the stator and the rotor has been studied.

  8. Motor cortical organization in an adult with hemimegalencephaly and late onset epilepsy.

    Science.gov (United States)

    Civardi, Carlo; Vicentini, Roberta; Collini, Alessandra; Boccagni, Cristina; Cantello, Roberto; Monaco, Francesco

    2009-08-28

    Hemimegalencephaly is a rare brain malformation whose physiology is largely obscure. In a single patient, we studied motor cortex using several transcranial magnetic stimulation variables testing cortical excitability, and mapping motor area. The megalencephalic hemisphere showed an enlargement of cortical motor map with abnormal axonal orientation and an excess spread of corticospinal excitation, associated with multiple defects of cortical inhibition. TMS gave new information on the anatomic/functional features and epileptogenesis in this complex and physiologically obscure syndrome.

  9. Corticospinal adaptations and strength maintenance in the immobilized arm following 3 weeks unilateral strength training.

    Science.gov (United States)

    Pearce, A J; Hendy, A; Bowen, W A; Kidgell, D J

    2013-12-01

    Cross-education strength training has being shown to retain strength and muscle thickness in the immobilized contralateral limb. Corticospinal mechanisms have been proposed to underpin this phenomenon; however, no transcranial magnetic stimulation (TMS) data has yet been presented. This study used TMS to measure corticospinal responses following 3 weeks of unilateral arm training on the contralateral, immobilize arm. Participants (n = 28) were randomly divided into either immobilized strength training (Immob + train) immobilized no training (Immob) or control. Participants in the immobilized groups had their nondominant arm rested in a sling, 15 h/day for 3 weeks. The Immob + train group completed unilateral arm curl strength training, while the Immob and control groups did not undertake training. All participants were tested for corticospinal excitability, strength, and muscle thickness of both arms. Immobilization resulted in a group x time significant reduction in strength, muscle thickness and corticospinal excitability for the untrained limb of the Immob group. Conversely, no significant change in strength, muscle thickness, or corticospinal excitability occurred in the untrained limb of the Immob + train group. These results provide the first evidence of corticospinal mechanisms, assessed by TMS, underpinning the use of unilateral strength training to retain strength and muscle thickness following immobilization of the contralateral limb.

  10. Unilateral practice of a ballistic movement causes bilateral increases in performance and corticospinal excitability.

    Science.gov (United States)

    Carroll, Timothy J; Lee, Michael; Hsu, Marlene; Sayde, Janel

    2008-06-01

    It has long been known that practicing a task with one limb can result in performance improvements with the opposite, untrained limb. Hypotheses to account for cross-limb transfer of performance state that the effect is mediated either by neural adaptations in higher order control centers that are accessible to both limbs, or that there is a "spillover" of neural drive to the opposite hemisphere that results in bilateral adaptation. Here we address these hypotheses by assessing performance and corticospinal excitability in both hands after unilateral practice of a ballistic finger movement. Participants (n = 9) completed 300 practice trials of a ballistic task with the right hand, the aim of which was to maximize the peak abduction acceleration of the index finger. Practice caused a 140% improvement in right-hand performance and an 82% improvement for the untrained left hand. There were bilateral increases in the amplitude of responses to transcranial magnetic stimulation, but increased corticospinal excitability was not correlated with improved performance. There were no significant changes in corticospinal excitability or task performance for a control group that did not train (n = 9), indicating that performance testing for the left hand alone did not induce performance or corticospinal effects. Although the data do not provide conclusive evidence whether increased corticospinal excitability in the untrained hand is causally related to the cross-transfer of ballistic performance, the finding that ballistic practice can induce bilateral corticospinal adaptations may have important clinical implications for movement rehabilitation.

  11. Vector-induced NT-3 expression in rats promotes collateral growth of injured corticospinal tract axons far rostral to a spinal cord injury.

    Science.gov (United States)

    Weishaupt, N; Mason, A L O; Hurd, C; May, Z; Zmyslowski, D C; Galleguillos, D; Sipione, S; Fouad, K

    2014-07-11

    Rewiring the injured corticospinal tract (CST) by promoting connections between CST axons and spared neurons is a strategy being explored experimentally to achieve improved recovery of motor function after spinal cord injury (SCI). Reliable interventions to promote and direct growth of collaterals from injured CST axons are in high demand to promote functionally relevant detour pathways. A promising tool is neurotrophin-3 (NT-3), which has shown growth-stimulating and chemo-attractive effects for spared CST axons caudal to a CST lesion. Yet, efforts to promote growth of injured CST axons rostral to a SCI with NT-3 have been less successful to date. Evidence indicates that immune activation in the local growth environment, either intrinsic or induced by the endotoxin lipopolysaccharide (LPS), can play a decisive role in the CST's responsiveness to NT-3. Here, we test the potential of NT-3 as a tool to enhance and direct collateral growth from the injured CST rostral to a SCI (1) using long-term expression of NT-3 by adeno-associated viral vectors, (2) with and without stimulating the immune system with LPS. Our results indicate that inducing a growth response from injured CST axons into a region of vector-mediated NT-3 expression is possible in the environment of the spinal cord rostral to a SCI, but seems dependent on the distance between the responding axon and the source of NT-3. Our findings also suggest that injured CST axons do not increase their growth response to NT-3 after immune activation with LPS in this environment. In conclusion, this is to our knowledge the first demonstration that NT-3 can be effective at promoting growth of injured CST collaterals far rostral to a SCI. Making NT-3 available in close proximity to CST target axons may be the key to success when using NT-3 to rewire the injured CST in future investigations.

  12. Linear motor system for sliding door for 209-series 950-generation electric railcar; 209 kei 950 dai densha soku hikidoyo rinia motor system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-10

    The system named above has been delivered to East Japan Railway Co. by Fuji Electric Co., Ltd., for use aboard the railway company`s prototype car to close the sliding door and is now in test use, the car designed to carry both commuters and suburbanites. This is the first product of the linear motor-driven type intended to close the sliding door aboard a railway car. Some features are stated below. The door lock and the door lock disengagement unit are improved, with their reliability enhanced. TIMS (train information management system) control and transmission enable the opening and closing of the door, supervision over the individual door state, parameter rewriting, etc., from the driver`s cab. Some base boards are added for shortening the rigging process. It is planned that a 1-linear motor drive system will be manufactured, lighter in weight, lower in power consumption, enhanced in safety, and reduced in cost, for installation aboard the car. (NEDO)

  13. Scaling of motor cortical excitability during unimanual force generation.

    Science.gov (United States)

    Perez, Monica A; Cohen, Leonardo G

    2009-10-01

    During performance of a unimanual force generation task primary motor cortices (M1s) experience clear functional changes. Here, we evaluated the way in which M1s interact during parametric increases in right wrist flexion force in healthy volunteers. We measured the amplitude and the slope of motor evoked potentials (MEP) recruitment curves to transcranial magnetic stimulation (TMS) in the left and right flexor carpi radialis (FCR) muscles at rest and during 10%, 30% and 70% of maximal wrist flexion force. At rest, no differences were observed in the amplitude and slope of MEP recruitment curves in the left and right FCR muscles. With increasing right wrist flexion force, MEP amplitudes increased in both FCR muscles, with larger amplitudes in the right FCR. We found a significant correlation between the left and right MEP amplitudes across conditions. The slope of right and left FCR MEP recruitment curve was significantly steeper at 70% of force compared to rest and 10% of force. A significant correlation between the slope of left and right FCR MEP amplitudes was found at 70% of force only. Our results indicate a differential scaling of excitability in the corticospinal system controlling right and left FCR muscles at increasing levels of unimanual force generation. Specifically, these data highlights that at strong levels of unimanual force the increases in motor cortical excitability with increasing TMS stimulus intensities follow a similar pattern in both M1s, while at low levels of force they do not.

  14. Modulation of motor cortex excitability by physical similarity with an observed hand action.

    Directory of Open Access Journals (Sweden)

    Marie-Christine Désy

    Full Text Available The passive observation of hand actions is associated with increased motor cortex excitability, presumably reflecting activity within the human mirror neuron system (MNS. Recent data show that in-group ethnic membership increases motor cortex excitability during observation of culturally relevant hand gestures, suggesting that physical similarity with an observed body part may modulate MNS responses. Here, we ask whether the MNS is preferentially activated by passive observation of hand actions that are similar or dissimilar to self in terms of sex and skin color. Transcranial magnetic stimulation-induced motor evoked potentials were recorded from the first dorsal interosseus muscle while participants viewed videos depicting index finger movements made by female or male participants with black or white skin color. Forty-eight participants equally distributed in terms of sex and skin color participated in the study. Results show an interaction between self-attributes and physical attributes of the observed hand in the right motor cortex of female participants, where corticospinal excitability is increased during observation of hand actions in a different skin color than that of the observer. Our data show that specific physical properties of an observed action modulate motor cortex excitability and we hypothesize that in-group/out-group membership and self-related processes underlie these effects.

  15. Preliminary evaluation of wheelchair occupant restraint system usage in motor vehicles.

    Science.gov (United States)

    van Roosmalen, Linda; Bertocci, Gina E; Hobson, Douglas A; Karg, Patricia

    2002-01-01

    Individuals using wheeled mobility devices (WMDs) often use them as motor vehicle seats during transportation. Wheelchair occupant restraint systems (WORSs), consisting of upper torso and pelvic restraints, are usually mounted to the structure of transit vehicles to secure individuals within their wheelchair seats. This preliminary study attempts to evaluate the use and satisfaction of currently installed vehicle-mounted WORSs for individuals using WMD as seats in motor vehicles. A survey was conducted among 33 adults who use their WMD to travel in motor vehicles. Results from the survey showed that upper torso and pelvic restraints installed in private vehicles are quick, comfortable, and easy to use. However, WORS installed in mass transit and paratransit are often uncomfortable to wear, difficult to reach, and time-consuming to use. This preliminary study documents the growing need for developing alternative WORS that are safe, comfortable, and that allow independent usage for wheelchair occupants while traveling in a motor vehicle.

  16. Information-Measuring System to Control the Electrical and Mechanical Motor Parameters

    Directory of Open Access Journals (Sweden)

    K. S. Ermakov

    2015-01-01

    Full Text Available The article considers the issue of creating an information-measuring system for an asynchronous motor. The presented system allows ensuring the failure-free protection of electromotor, considerably reducing costs of its unplanned repair, and reduced economical loss from idle time of the electric motor.The developed system comprises a mathematical model and two subsystems to measure electrical and mechanical parameters of the asynchronous motor.The electrical subsystem comprises a FLUKE company recording multi-meter a signal from which passes through the block of intervals and coding and comes to PC.The mechanical subsystem uses technical tools of phase-chronometric method. This method developed at the department of Metrology and Interchangeability allows an increasing efficiency of developed informative-measuring system. Mathematical modeling is used to link information from subsystems (electrical and mechanical to electromotor construction.The work conducted mathematical modeling of some defects of electric motor, namely: rupture of rotor winding and line surge.The mathematical model in Mathcad was based on a modified formula of Kloss. It allows us to tie the average current value of the torque of the induction motor with shaft speed and take into account the effect of the frequency and voltage.The Matlab Simulink (the package for visual programming environment was used to simulate a rupture of the rotor winding. Simulation results showed how the phase currents of the electric motor changed with the winding rupture.The developed information-measuring system has a number of advantages over traditional systems used in this field (vibration-based diagnostics systems. It will allow an increasing efficiency of the system for diagnostics of electrical machines created on the basis of this information-measuring system.

  17. Noise Source Identification of Small Fan-BLDC Motor System for Refrigerators

    Directory of Open Access Journals (Sweden)

    Yong-Han Kim

    2006-01-01

    Full Text Available Noise levels in household appliances are increasingly attracting attention from manufacturers and customers. Legislation is becoming more severe on acceptable noise levels and low noise is a major marketing point for many products. The latest trend in the refrigerator manufacturing industry is to use brushless DC (BLDC motors instead of induction motors in order to reduce energy consumption and noise radiation. However, cogging torque from BLDC motor is an undesirable effect that prevents the smooth rotation of the rotor and results in noise. This paper presents a practical approach for identifying the source of excessive noise in the small fan-motor system for household refrigerators. The source is presumed to a mechanical resonance excited by torque ripple of the BLDC motor. By using finite element analysis, natural frequencies and mode shapes of the rotating part of the system are obtained and they are compared with experimental mode shapes obtained by electronic torsional excitation test which uses BLDC motor itself as an exciter. Two experimental validations are carried out to confirm the reduction of excessive noise.

  18. Research of Compound Control for DC Motor System Based on Global Sliding Mode Disturbance Observer

    Directory of Open Access Journals (Sweden)

    He Zhang

    2014-01-01

    Full Text Available Aiming at the problems of modeling errors, parameter variations, and load moment disturbances in DC motor control system, one global sliding mode disturbance observer (GSMDO is proposed based on the global sliding mode (GSM control theory. The output of GSMDO is used as the disturbance compensation in control system, which can improve the robust performance of DC motor control system. Based on the designed GSMDO in inner loop, one compound controller, composed of a feedback controller and a feedforward controller, is proposed in order to realize the position tracking of DC motor system. The gains of feedback controller are obtained by means of linear quadratic regulator (LQR optimal control theory. Simulation results present that the proposed control scheme possesses better tracking properties and stronger robustness against modeling errors, parameter variations, and friction moment disturbances. Moreover, its structure is simple; therefore it is easy to be implemented in engineering.

  19. Motor Neurons

    DEFF Research Database (Denmark)

    Hounsgaard, Jorn

    2017-01-01

    Motor neurons translate synaptic input from widely distributed premotor networks into patterns of action potentials that orchestrate motor unit force and motor behavior. Intercalated between the CNS and muscles, motor neurons add to and adjust the final motor command. The identity and functional...... properties of this facility in the path from synaptic sites to the motor axon is reviewed with emphasis on voltage sensitive ion channels and regulatory metabotropic transmitter pathways. The catalog of the intrinsic response properties, their underlying mechanisms, and regulation obtained from motoneurons...... in in vitro preparations is far from complete. Nevertheless, a foundation has been provided for pursuing functional significance of intrinsic response properties in motoneurons in vivo during motor behavior at levels from molecules to systems....

  20. Motor cortex excitability and connectivity in chronic stroke: a multimodal model of functional reorganization.

    Science.gov (United States)

    Volz, Lukas J; Sarfeld, Anna-Sophia; Diekhoff, Svenja; Rehme, Anne K; Pool, Eva-Maria; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

    2015-03-01

    Cerebral ischemia triggers a cascade of cellular processes, which induce neuroprotection, inflammation, apoptosis and regeneration. At the neural network level, lesions concomitantly induce cerebral plasticity. Yet, many stroke survivors are left with a permanent motor deficit, and only little is known about the neurobiological factors that determine functional outcome after stroke. Transcranial magnetic stimulation (TMS) and magnetic resonance imaging (MRI) are non-invasive approaches that allow insights into the functional (re-) organization of the cortical motor system. We here combined neuronavigated TMS, MRI and analyses of connectivity to investigate to which degree recovery of hand function depends on corticospinal tract (CST) damage and biomarkers of cerebral plasticity like cortical excitability and motor network effective connectivity. As expected, individual motor performance of 12 stroke patients with persistent motor deficits was found to depend upon the degree of CST damage but also motor cortex excitability and interhemispheric connectivity. In addition, the data revealed a strong correlation between reduced ipsilesional motor cortex excitability and reduced interhemispheric inhibition in severely impaired patients. Interindividual differences in ipsilesional motor cortex excitability were stronger related to the motor deficit than abnormal interhemispheric connectivity or CST damage. Multivariate linear regression analysis combining the three factors accounted for more than 80 % of the variance in functional impairment. The inter-relation of cortical excitability and reduced interhemispheric inhibition provides direct multi-modal evidence for the disinhibition theory of the contralesional hemisphere following stroke. Finally, our data reveal a key mechanism (i.e., the excitability-related reduction in interhemispheric inhibition) accounting for the rehabilitative potential of novel therapeutic approaches which aim at modulating cortical

  1. Development of a Simulink/RTW-Based Realtime Control System for an Induction Motor Vector Control

    Energy Technology Data Exchange (ETDEWEB)

    Kang, M. H. [Sunmoon University, Chonan (Korea)

    2001-03-01

    In this research a Simulink/RTW-based realtime control system was developed for an induction motor vector control. On the Simulink window, the control system is designed in the form of block diagrams, program codes are produced automatically with the RTW(Real Time Workshop), then an DSP c compiles the program codes. With this automatic program producing method rapid prototyping is realized with the least time-consuming manual programming procedures. To show effectiveness of the proposed system designing scheme a DSP-based induction motor vector controller was constructed and implemented. (author). 10 refs., 15 figs., 2 tabs.

  2. Presentation of CAE system for motor sports vehicle chassis development; Motor sports sharyo no shassis kaihatsuyo CAE system no shokai

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, N.; Ueda, E. [Nissan Motor Co. Ltd., Tokyo (Japan)

    2000-02-01

    In the recent motor sports vehicle development introduction of a new model in a short cycle to secure high competition ability shortens the period from its completion to the race. And application of embedded controls makes development process more complicated. In this circumstance, predictive development style becomes more important in order to achieve the performance at high level when the new car is at shakedown. In this paper, summary and the application examples are presented with regard to three important CAE tools such as lap time simulation, vehicle dynamics simulation and suspension kinematics simulation which are developed to realize the said development style. (author)

  3. Dynamic Performance of Subway Vehicle with Linear Induction Motor System

    Science.gov (United States)

    Wu, Pingbo; Luo, Ren; Hu, Yan; Zeng, Jing

    The light rail vehicle with Linear Induction Motor (LIM) bogie, which is a new type of urban rail traffic tool, has the advantages of low costs, wide applicability, low noise, simple maintenance and better dynamic behavior. This kind of vehicle, supported and guided by the wheel and rail, is not driven by the wheel/rail adhesion force, but driven by the electromagnetic force between LIM and reaction plate. In this paper, three different types of suspensions and their characteristic are discussed with considering the interactions both between wheel and rail and between LIM and reaction plate. A nonlinear mathematical model of the vehicle with LIM bogie is set up by using the software SIMPACK, and the electromechanical model is also set up on Simulink roof. Then the running behavior of the LIM vehicle is simulated, and the influence of suspension on the vehicle dynamic performance is investigated.

  4. A Novel MagPipe Pipeline transportation system using linear motor drives

    Energy Technology Data Exchange (ETDEWEB)

    Fang, J.R.; Montgomery, D.B.; Roderick, L. [Magplane Technology Inc., Littleton, MA (United States)

    2009-11-15

    A novel capsule pipeline transportation system using linear motor drives, called Magplane MagPipe, is under development with the intention to replace trucks and railways for hauling materials from the mine to the rail head, power plant, or processing plant with reduced operating cost and energy consumption. The initial demonstration of a MagPipe line in Inner Mongolia will be a 500-m-long double-pipe coal transport system with the design transportation capacity of 3 Mega-Mg per year. The pipeline consists of 6-m-long plastic pipe modules with an I-beam suspension system inside the pipe to carry sets of five coupled capsules. The pipe will also contain noncontinuous motor winding modules spaced at 50-m intervals. A set of Halbach-arrayed permanent magnets on the bottom of the capsules interact with the linear motor windings to provide propulsion. The motor is driven by variable frequency drives outside the pipe to control the speed. This paper briefly describes the overall MagPipe pipeline transportation system, including the preliminary conclusions of the linear synchronous motor analysis.

  5. Optimism system refrigerator hybrid power (solar cell + actuator motor to traditional fisherman boat in Makassar

    Directory of Open Access Journals (Sweden)

    Soetyono Ch. Iskandar

    2016-10-01

    Full Text Available Research of Pre-eminent Donation of This college aimed at energetic refrigerator system planning of hybrid (solar cell + actuator motor at inclusion ship of fish in coming, principal from this research is, exploiting of dissociation energy of diatomic is newest with usage of diesel fuel technology cell as coolant system actuator at actuator motor plus fisherman ship. This research program planned in a period of three years to design freezing device of energetic fish of hybrid (solarcell + actuator motor fisherman ship, yields storage device basis barium product of energetic fish of hybrid.In first year, does with refer to study study about base material refrigerator and solar cell and makes energetic refrigerator system prototype of solar (laboratory scale. In second year, does study to design energetic refrigerator of hybrid (solar cell + actuator motor with laboratory scale productively energetic refrigerator prototype of hybrid with laboratory scale. In third year, application of energetic refrigerator system of hybrid (solar cell + actuator motor at fisherman ship Poetere in Makassar, expected can push and motivates fisherman public in developing and applies this technology, causing can increase quality of produce of fish and at the same time increases fisherman public economics value without using again ice block to make cool fisherman fishing boat hold.

  6. SDF1 in the dorsal corticospinal tract promotes CXCR4+ cell migration after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Jung Hosung

    2011-02-01

    Full Text Available Abstract Background Stromal cell-derived factor-1 (SDF1 and its major signaling receptor, CXCR4, were initially described in the immune system; however, they are also expressed in the nervous system, including the spinal cord. After spinal cord injury, the blood brain barrier is compromised, opening the way for chemokine signaling between these two systems. These experiments clarified prior contradictory findings on normal expression of SDF1 and CXCR4 as well as examined the resulting spinal cord responses resulting from this signaling. Methods These experiments examined the expression and function of SDF1 and CXCR4 in the normal and injured adult mouse spinal cord primarily using CXCR4-EGFP and SDF1-EGFP transgenic reporter mice. Results In the uninjured spinal cord, SDF1 was expressed in the dorsal corticospinal tract (dCST as well as the meninges, whereas CXCR4 was found only in ependymal cells surrounding the central canal. After spinal cord injury (SCI, the pattern of SDF1 expression did not change rostral to the lesion but it disappeared from the degenerating dCST caudally. By contrast, CXCR4 expression changed dramatically after SCI. In addition to the CXCR4+ cells in the ependymal layer, numerous CXCR4+ cells appeared in the peripheral white matter and in the dorsal white matter localized between the dorsal corticospinal tract and the gray matter rostral to the lesion site. The non-ependymal CXCR4+ cells were found to be NG2+ and CD11b+ macrophages that presumably infiltrated through the broken blood-brain barrier. One population of macrophages appeared to be migrating towards the dCST that contains SDF1 rostral to the injury but not towards the caudal dCST in which SDF1 is no longer present. A second population of the CXCR4+ macrophages was present near the SDF1-expressing meningeal cells. Conclusions These observations suggest that attraction of CXCR4+ macrophages is part of a programmed response to injury and that modulation of the

  7. Low-Cost Undergraduate Control Systems Experiments Using Microcontroller-Based Control of a DC Motor

    Science.gov (United States)

    Gunasekaran, M.; Potluri, R.

    2012-01-01

    This paper presents low-cost experiments for a control systems laboratory module that is worth one and a third credits. The experiments are organized around the microcontroller-based control of a permanent magnet dc motor. The experimental setups were built in-house. Except for the operating system, the software used is primarily freeware or free…

  8. Conversational Rate of a Non-Vocal Person with Motor Neurone Disease Using the 'TALK' System.

    Science.gov (United States)

    Todman, J.; Lewins, E.

    1996-01-01

    This study evaluated the use of TALK, a computer-based augmentative and alternative communication (AAC) system, in the social communications of a nonvocal woman with motor neurone disease. She was able to achieve an average conversational rate of 42 words per minute (wpm) using TALK, compared with 2 to 10 wpm with other AAC systems using…

  9. Finite-Time Chaos Suppression of Permanent Magnet Synchronous Motor Systems

    Directory of Open Access Journals (Sweden)

    Yi-You Hou

    2014-04-01

    Full Text Available This paper considers the problem of the chaos suppression for the Permanent Magnet Synchronous Motor (PMSM system via the finite-time control. Based on Lyapunov stability theory and the finite-time controller are developed such that the chaos behaviors of PMSM system can be suppressed. The effectiveness and accuracy of the proposed methods are shown in numerical simulations.

  10. Only Self-Generated Actions Create Sensori-Motor Systems in the Developing Brain

    Science.gov (United States)

    James, Karin Harman; Swain, Shelley N.

    2011-01-01

    Previous research shows that sensory and motor systems interact during perception, but how these connections among systems are created during development is unknown. The current work exposes young children to novel "verbs" and objects through either (a) actively exploring the objects or (b) by seeing an experimenter interact with the objects.…

  11. Low-Cost Undergraduate Control Systems Experiments Using Microcontroller-Based Control of a DC Motor

    Science.gov (United States)

    Gunasekaran, M.; Potluri, R.

    2012-01-01

    This paper presents low-cost experiments for a control systems laboratory module that is worth one and a third credits. The experiments are organized around the microcontroller-based control of a permanent magnet dc motor. The experimental setups were built in-house. Except for the operating system, the software used is primarily freeware or free…

  12. 77 FR 44673 - Meeting of the Department of Justice National Motor Vehicle Title Information System Federal...

    Science.gov (United States)

    2012-07-30

    ... Vehicle Title Information System (NMVTIS) Federal Advisory Committee to discuss various issues relating to... of Justice Programs Meeting of the Department of Justice National Motor Vehicle Title Information System Federal Advisory Committee AGENCY: Office of Justice Programs (OJP), Justice. ACTION: Notice...

  13. New method for computing unstable equilibrium points of power systems with induction motors

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The computation of the unstable equilibrium point(UEP) is a key step involved in stability region estimation of nonlinear dynamic systems.A new continuation-based method to compute the UEPs of a power system with induction motors is proposed.The mechanical torques of motors are changed to form a parameterized equation set.Then the solution curve of the equation set is traced by the continuation method from the stable equilibrium point to a UEP.The direction of mechanical torque change is varied to get multiple UEPs.The obtained UEPs are mostly type-1.Then fast assessment of induction motor stability is studied by approximating the stable manifolds of the UEPs.The method is tested in several systems and satisfactory results are obtained.

  14. Common-mode Voltage Reduction in a Motor Drive System with a Power Factor Correction

    DEFF Research Database (Denmark)

    Adabi, J.; Boora, A.A.; Zare, F.;

    2012-01-01

    to reduce shaft voltage in a three-phase AC motor drive system. In this topology, the AC-DC diode rectifier influences the common-mode voltage generated by the inverter because the placement of the neutral point is changing in different rectifier circuit states. A pulse width modulation technique......Common-mode voltage generated by a power converter in combination with parasitic capacitive couplings is a potential source of shaft voltage in an AC motor drive system. In this study, a three-phase motor drive system supplied with a single-phase AC-DC diode rectifier is investigated in order...... is presented by a proper placement of the zero vectors to reduce the common-mode voltage level, which leads to a cost-effective shaft voltage reduction technique without load current distortion, while keeping the switching frequency constant. Analysis, simulations and experimental implementation have been...

  15. Motor-Skill Learning in an Insect Inspired Neuro-Computational Control System

    Science.gov (United States)

    Arena, Eleonora; Arena, Paolo; Strauss, Roland; Patané, Luca

    2017-01-01

    In nature, insects show impressive adaptation and learning capabilities. The proposed computational model takes inspiration from specific structures of the insect brain: after proposing key hypotheses on the direct involvement of the mushroom bodies (MBs) and on their neural organization, we developed a new architecture for motor learning to be applied in insect-like walking robots. The proposed model is a nonlinear control system based on spiking neurons. MBs are modeled as a nonlinear recurrent spiking neural network (SNN) with novel characteristics, able to memorize time evolutions of key parameters of the neural motor controller, so that existing motor primitives can be improved. The adopted control scheme enables the structure to efficiently cope with goal-oriented behavioral motor tasks. Here, a six-legged structure, showing a steady-state exponentially stable locomotion pattern, is exposed to the need of learning new motor skills: moving through the environment, the structure is able to modulate motor commands and implements an obstacle climbing procedure. Experimental results on a simulated hexapod robot are reported; they are obtained in a dynamic simulation environment and the robot mimicks the structures of Drosophila melanogaster. PMID:28337138

  16. Mechanical - physical treatment of used motor oil within a sustainable waste management system

    Directory of Open Access Journals (Sweden)

    Đukić Veljko N.

    2015-01-01

    Full Text Available Waste oils are all mineral or synthetic oils that cannot be used for the purpose for which they were originally produced. These are: hydraulic oils, motor oils, ship oils, liquids for the transfer of heat or insulation, oily remains from reservoirs, oil-water emulsions and various oil-water mixtures. In its chemical makeup used motor oil contains hydrocarbons, organic minerals, heavy metals (cobalt, magnesium, iron, zinc, sulfur, chlorine, nitrogen, phosphorus, compounds from additives and other products that are dangerous as they have cancerous effects on health. As it is considered the biggest contaminant of the environment and classified as hazardous waste; special attention must be given in the handling of used motor oil to ensure its appropriate disposal. Setting up of a viable system for Mechanical-Physical Treatment of used motor oil makes it possible to re-use it as a secondary raw material i.e. the problem of collection, transportation, treatment and storing of the used motor oil is being solved. . The subject of this research is the advantage of the mechanical-physical treatment of used motor oil. Re- refined motor oil can be used for multiple purposes such as a base for the other synthetic oils, for heating etc. Improper disposal of used motor oil causes multiple damage; firstly, losing the valuable secondary base which, with the addition of certain additives, can be used as the basis for the other synthetic oils; secondly, causing damage to the environment by the pollution with inability to repair the damage to all environmental components.

  17. An augmented reality system for upper-limb post-stroke motor rehabilitation: a feasibility study.

    Science.gov (United States)

    Assis, Gilda Aparecida de; Corrêa, Ana Grasielle Dionísio; Martins, Maria Bernardete Rodrigues; Pedrozo, Wendel Goes; Lopes, Roseli de Deus

    2016-08-01

    To determine the clinical feasibility of a system based on augmented reality for upper-limb (UL) motor rehabilitation of stroke participants. A physiotherapist instructed the participants to accomplish tasks in augmented reality environment, where they could see themselves and their surroundings, as in a mirror. Two case studies were conducted. Participants were evaluated pre- and post-intervention. The first study evaluated the UL motor function using Fugl-Meyer scale. Data were compared using non-parametric sign tests and effect size. The second study used the gain of motion range of shoulder flexion and abduction assessed by computerized biophotogrammetry. At a significance level of 5%, Fugl-Meyer scores suggested a trend for greater UL motor improvement in the augmented reality group than in the other. Moreover, effect size value 0.86 suggested high practical significance for UL motor rehabilitation using the augmented reality system. System provided promising results for UL motor rehabilitation, since enhancements have been observed in the shoulder range of motion and speed. Implications for Rehabilitation Gain of range of motion of flexion and abduction of the shoulder of post-stroke patients can be achieved through an augmented reality system containing exercises to promote the mental practice. NeuroR system provides a mental practice method combined with visual feedback for motor rehabilitation of chronic stroke patients, giving the illusion of injured upper-limb (UL) movements while the affected UL is resting. Its application is feasible and safe. This system can be used to improve UL rehabilitation, an additional treatment past the traditional period of the stroke patient hospitalization and rehabilitation.

  18. Effect of biased feedback on motor imagery learning in BCI-teleoperation system

    Directory of Open Access Journals (Sweden)

    Maryam eAlimardani

    2014-04-01

    Full Text Available Feedback design is an important issue in motor imagery BCI systems. Regardless, to date it has not been reported how feedback presentation can optimize co-adaptation between a human brain and such systems. This paper assesses the effect of realistic visual feedback on users’ BC performance and motor imagery skills. We previously developed a tele-operation system for a pair of humanlike robotic hands and showed that BCI control of such hands along with first-person perspective visual feedback of movements can arouse a sense of embodiment in the operators. In the first stage of this study, we found that the intensity of this ownership illusion was associated with feedback presentation and subjects’ performance during BCI motion control. In the second stage, we probed the effect of positive and negative feedback bias on subjects’ BCI performance and motor imagery skills. Although the subject specific classifier, which was set up at the beginning of experiment, detected no significant change in the subjects’ online performance, evaluation of brain activity patterns revealed that subjects’ self-regulation of motor imagery features improved due to a positive bias of feedback and a possible occurrence of ownership illusion. Our findings suggest that in general training protocols for BCIs, manipulation of feedback can play an important role in the optimization of subjects’ motor imagery skills.

  19. Real-Time Brain-Computer Interface System Based on Motor Imagery

    Institute of Scientific and Technical Information of China (English)

    Tie-Jun Liu; Ping Yang; Xu-Yong Peng; Yu Huang; De-Zhong Yao

    2009-01-01

    A brain-computer interface (BCI) real-time system based on motor imagery translates the user's motor intention into a real-time control signal for peripheral equipments.A key problem to be solved for practical applications is real-time data collection and processing.In this paper,a real-time BCI system is implemented on computer with electroencephalogram amplifier.In our implementation,the on-line voting method is adopted for feedback control strategy,and the voting results are used to control the cursor horizontal movement.Three subjects take part in the experiment.The results indicate that the best accuracy is 90%.

  20. Differences in corticospinal excitability to the biceps brachii between arm cycling and tonic contraction are not evident at the immediate onset of movement.

    Science.gov (United States)

    Forman, Davis A; Philpott, Devin T G; Button, Duane C; Power, Kevin E

    2016-08-01

    This is the first study to examine changes in corticospinal excitability to the biceps brachii during the onset of arm cycling from a resting position to a point when steady-state arm cycling was obtained. Supraspinal and spinal excitability were assessed using motor-evoked potentials (MEPs) elicited via transcranial magnetic stimulation and cervicomedullary evoked potentials (CMEPs) elicited via transmastoid electrical stimulation, respectively. Evoked responses were recorded from the biceps brachii during elbow flexion (6 o'clock relative to a clock face) for both arm cycling and an intensity-matched tonic contraction at three separate periods: (1) immediately at the onset of motor output and after completion of the (2) 4th revolution and (3) 9th revolution. There was no difference during initiation between tasks for MEP (P = 0.79) or CMEP amplitudes (P = 0.57). However, MEP amplitudes were significantly larger during arm cycling than an intensity-matched tonic contraction after the completion of the 4th (Cycling 76.48 ± 17.35 % of M max, Tonic 63.45 ± 18.45 % of M max, P Cycling 72.37 ± 15.96 % of M max, Tonic 58.1 ± 24.23 % of M max, P Cycling 49.6 ± 25.4 % of M max, Tonic 41.6 ± 11.2 % of M max, P = 0.31) or the 9th revolution (Cycling 47.2 ± 17.0 % of M max, Tonic 40.8 ± 13.6 % of M max, P = 0.29). These results demonstrate that corticospinal excitability is not different between arm cycling and a tonic contraction at motor output onset, but supraspinal excitability is enhanced during steady-state arm cycling. This suggests a similarity in the way the corticospinal tract initiates motor outputs in humans, regardless of the differences that present themselves in the later, steady-state stages.

  1. Effects of methylphenidate on motor system excitability in a response inhibition task

    Directory of Open Access Journals (Sweden)

    Moll Gunther H

    2009-02-01

    Full Text Available Abstract Background Motor system excitability is based on a complex interaction of excitatory and inhibitory processes, which in turn are modulated by internal (e.g., volitional inhibition and external (e.g., drugs factors. A well proven tool to investigate motor system excitability in vivo is the transcranial magnetic stimulation (TMS. In this study, we used TMS to investigate the effects of methylphenidate (MPH on the temporal dynamics of motor system excitability during a go/nogo task. Methods Using a double-blind, placebo-controlled, crossover design, 14 healthy adults (8 male, 6 female; aged 20–40 yrs performed a spatial go/nogo task (S1-S2 paradigm either under dl-methylphenidate (MPH, 20 mg or placebo. TMS single and double-pulses (interstimulus interval: 3 ms were delivered either at 120, 230 or 350 ms after the S2 stimulus (control, go and nogo trials. Results At the performance level, faster reaction times and a trend towards less impulsivity errors under MPH vs. placebo were observed. In nogo trials, i.e., when a prepared response had to be inhibited, motor evoked potentials (MEPs had a smaller amplitude at an interval of 230 ms compared to 120 and 350 ms. The short-interval intracortical inhibition (SICI increased over time. Under MPH, SICI in nogo trials was larger compared to placebo. With the interval between S2 and the TMS-pulse increasing, MEP amplitudes increased under MPH in nogo trials but an early inhibitory effect (at 120 ms could also be observed. Conclusion Our results show a distinct pattern of excitatory and inhibitory phenomena in a go/nogo task. MPH appears to significantly alter the dynamics of motor system excitability. Our findings suggest that a single dose of 20 mg MPH provides some fine-tuning of the motor system in healthy adults.

  2. High frequency vibration characteristics of electric wheel system under in-wheel motor torque ripple

    Science.gov (United States)

    Mao, Yu; Zuo, Shuguang; Wu, Xudong; Duan, Xianglei

    2017-07-01

    With the introduction of in-wheel motor, the electric wheel system encounters new vibration problems brought by motor torque ripple excitation. In order to analyze new vibration characteristics of electric wheel system, torque ripple of in-wheel motor based on motor module and vector control system is primarily analyzed, and frequency/order features of the torque ripple are discussed. Then quarter vehicle-electric wheel system (QV-EWS) dynamics model based on the rigid ring tire assumption is established and the main parameters of the model are identified according to tire free modal test. Modal characteristics of the model are further analyzed. The analysis indicates that torque excitation of in-wheel motor is prone to arouse horizontal vibration, in which in-phase rotational, anti-phase rotational and horizontal translational modes of electric wheel system mainly participate. Based on the model, vibration responses of the QV-EWS under torque ripple are simulated. The results show that unlike vertical low frequency (lower than 20 Hz) vibration excited by road roughness, broadband torque ripple will arouse horizontal high frequency (50-100 Hz) vibration of electric wheel system due to participation of the three aforementioned modes. To verify the theoretical analysis, the bench experiment of electric wheel system is conducted and vibration responses are acquired. The experiment demonstrates the high frequency vibration phenomenon of electric wheel system and the measured order features as well as main resonant frequencies agree with simulation results. Through theoretical modeling, analysis and experiments this paper reveals and explains the high frequency vibration characteristics of electric wheel system, providing references for the dynamic analysis, optimal design of QV-EWS.

  3. The Number of Pulses Needed to Measure Corticospinal Excitability by Navigated Transcranial Magnetic Stimulation: Eyes Open vs. Close Condition

    Science.gov (United States)

    Bashir, Shahid; Yoo, Woo-Kyoung; Kim, Hyoung Seop; Lim, Hyun Sun; Rotenberg, Alexander; Abu Jamea, Abdullah

    2017-01-01

    Objective: Motor evoked potentials (MEPs) obtained by transcranial magnetic stimulation (TMS) enable measures of the corticospinal excitability (CSE). However the reliability of TMS-derived CSE measures is suboptimal due to appreciable pulse-to-pulse MEP amplitude variability. We thus calculated how many TMS–derived MEPs will be needed to obtain a reliable CSE measure in awake adult subjects, in the eyes open (EO) and eyes closed (EC) conditions. Methods: Twenty healthy adults (70% male) received 40 consecutive navigated TMS pulses (120% resting motor threshold, RMT) in the EO or EC conditions on two separate days in randomized order. Results: For either the EO or EC condition, the probability that the 95% confidence interval (CI) derived from consecutive MEP amplitude measured included the true CSE, increased when the number of consecutive stimuli increased (EO: p = 0.05; EC: p = 0.001). No significant effect of RMT, Mini-Mental State Examination (MMSE) score, or gender on the CSE estimates was identified. At least 34 consecutive stimuli were required to obtain a most reliable CSE estimate in the EO condition and 31 in the EC condition. Conclusion: Our findings indicate that >30 consecutive MEPs may be necessary in order to obtain a CSE measure in healthy adults.

  4. CHARACTERISTICS OF ELECTROMECHANICAL COUPLING SELF-SYNCHRONIZATION OF A MULTI-MOTOR VIBRATION TRANSMISSION SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Multi-motor vibratory transmission systems have been wide used in large vibratory machines, and four-motor linear vibratory machine is one typical equipment of them. Under non-forcible synchronization condition zero-phase synchronization of the machine is non-stationary and π-phase synchronization is stable. Under half-forcible synchronization condition in which only one motor is controlled being synchronous to another, only lag synchronization near zero-phase synchronization can be realized. Both of the characteristics have never been revealed with classical theory quantitatively. The problem is solved by means of establishing an electromechanical coupling mathematical model of the system and numerical analysis of the starting processes.

  5. A Wireless Sensor System for Real-Time Monitoring and Fault Detection of Motor Arrays

    Science.gov (United States)

    Medina-García, Jonathan; Sánchez-Rodríguez, Trinidad; Galán, Juan Antonio Gómez; Delgado, Aránzazu; Gómez-Bravo, Fernando; Jiménez, Raúl

    2017-01-01

    This paper presents a wireless fault detection system for industrial motors that combines vibration, motor current and temperature analysis, thus improving the detection of mechanical faults. The design also considers the time of detection and further possible actions, which are also important for the early detection of possible malfunctions, and thus for avoiding irreversible damage to the motor. The remote motor condition monitoring is implemented through a wireless sensor network (WSN) based on the IEEE 802.15.4 standard. The deployed network uses the beacon-enabled mode to synchronize several sensor nodes with the coordinator node, and the guaranteed time slot mechanism provides data monitoring with a predetermined latency. A graphic user interface offers remote access to motor conditions and real-time monitoring of several parameters. The developed wireless sensor node exhibits very low power consumption since it has been optimized both in terms of hardware and software. The result is a low cost, highly reliable and compact design, achieving a high degree of autonomy of more than two years with just one 3.3 V/2600 mAh battery. Laboratory and field tests confirm the feasibility of the wireless system. PMID:28245623

  6. Evaluation of corticospinal tract injury with three-dimensional diffusion tensor tract in patients with acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Hui Xiao; Ziqian Chen; Biyun Zhang; Ping Ni

    2006-01-01

    BACKGROUND: Three-dimensional diffusion tensor tract (DTT) is the newest imaging to describe the structure of white matter fiber in three-dimensions, it has great significance in dividing the concrete anatomic site of gray and white matter lesions, displaying the correlation with fibrous band and judging clinical prognosis, which is incomparable by other imagings.OBJECTTVE: To observe the conditions of corticospinal tract (CST) in acute cerebral ischemic stroke patients,and analyze the relationship between motor function and the severity of CST injury.DESIGN: A case-control observation.SETTTNG: Department of Medical Imaging, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA.PARTTCTPANTS: Fifteen patients with acute cerebral infarction were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from February to December in 2005. They all suffered from acute attack and motor disorder of hemiplegic limbs to different extent, and were conformed by CT or MRI.There were 9 males and 6 females, aging 16-87 years old, the median age was 51.7 years, and all were right handed. Fifteen right-handed normal subjects, who were matched by age and sex with the patients in the cerebral infarction group, were selected from the relatives of patients and physicians of the Imaging Department as the control group. All the subjects were informed and agreed with the study.METHODS: The patients with acute cerebral infarction and subjects in the control group received MR diffusion tensor imaging (DTI) with GE 1.5 T nuclear magnetic resonance system, fiber tracking with the software of dTV- Ⅱ. Fractional anisotropy (FA) maps and three-dimensional tractography of bilateral CST of all patients were created. Displacement, continuity and destroy of fibrous bands were observed. At the same time, muscle strength of ipsilateral hand of patients with cerebral infarction was measured with Brunnstrom standard. The correlation between the severity

  7. Electromagnetic interference in electrical systems of motor vehicles

    Science.gov (United States)

    Dziubiński, M.; Drozd, A.; Adamiec, M.; Siemionek, E.

    2016-09-01

    Electronic ignition system affects the electronic equipment of the vehicle by electric and magnetic fields. The measurement of radio electromagnetic interference originating from the ignition system affecting the audiovisual test bench was carried out with a variable speed of the ignition system. The paper presents measurements of radio electromagnetic interference in automobiles. In order to determine the level of electromagnetic interference, the audiovisual test bench was equipped with a set of meters for power consumption and assessment of the level of electromagnetic interference. Measurements of the electromagnetic interference level within the audiovisual system were performed on an experimental test bench consisting of the ignition system, starting system and charging system with an alternator and regulator.

  8. Developing an intelligent control system of automatic window motor with diverse wireless sensor network devices

    Indian Academy of Sciences (India)

    Yao-Chiang Kan; Hsueh-Chun Lin; Wen-Pei Sung

    2014-08-01

    This invention system involves hardware, firmware and software to develop an intelligent control system of automatic window motor with diverse wireless sensor network (WSN) devices for health and environmental monitoring. The parts of this invention are improved by implementing the WSN mote into environmental sensors that may detect temperature, humility, toxic gas, smog or aerosol, etc. With embedded system design, these sensors are capable of delivering WSN signal packets based on ZigBee protocol that follows the IEEE 802.14.4 standards. The primary hardware of the system is the window motor with circuit design by integrating micro control unit (MCU), radio frequency (RF) and WSN antenna to receive command. The firmware developed under embedded system can bridge hardware and software to control the window at the specified position. At the back end, the control system software can manage diverse sensor data and provide the interface for remote monitoring.

  9. Synchronous EMG activity in the piper frequency band reveals the corticospinal demand of walking tasks.

    Science.gov (United States)

    Clark, David J; Kautz, Steven A; Bauer, Andrew R; Chen, Yen-Ting; Christou, Evangelos A

    2013-08-01

    Evidence indicates that the frequency-domain characteristics of surface electromyogram (EMG) signals are modulated according to the contributing sources of neural drive. Modulation of inter-muscular EMG synchrony within the Piper frequency band (30-60 Hz) during movement tasks has been linked to drive from the corticospinal tract. However, it is not known whether EMG synchrony is sufficiently sensitive to detect task-dependent differences in the corticospinal contribution to leg muscle activation during walking. We investigated this question in seventeen healthy older men and women. It was hypothesized that, relative to typical steady state walking, Piper band EMG synchrony of the triceps surae muscle group would be reduced for dual-task walking (because of competition for cortical resources), similar for fast walking (because walking speed is directed by an indirect locomotor pathway rather than by the corticospinal tract), and increased when taking a long step (because voluntary gait pattern modifications are directed by the corticospinal tract). Each of these hypotheses was confirmed. These findings support the use of frequency-domain analysis of EMG in future investigations into the corticospinal contribution to control of healthy and disordered human walking.

  10. Synchronous EMG activity in the Piper frequency band reveals the corticospinal demand of walking tasks

    Science.gov (United States)

    Clark, David J.; Kautz, Steven A.; Bauer, Andrew R.; Chen, Yen-Ting; Christou, Evangelos A.

    2013-01-01

    Evidence indicates that the frequency-domain characteristics of surface electromyogram (EMG) signals are modulated according to the contributing sources of neural drive. Modulation of inter-muscular EMG synchrony within the Piper frequency band (30–60Hz) during movement tasks has been linked to drive from the corticospinal tract. However, it is not known whether EMG synchrony is sufficiently sensitive to detect task-dependent differences in the corticospinal contribution to leg muscle activation during walking. We investigated this question in seventeen healthy older men and women. It was hypothesized that, relative to typical steady state walking, Piper band EMG synchrony of the triceps surae muscle group would be reduced for dual-task walking (because of competition for cortical resources), similar for fast walking (because walking speed is directed by an intermediate locomotor pathway rather than by the corticospinal tract), and increased when taking a long step (because voluntary gait pattern modifications are directed by the corticospinal tract). Each of these hypotheses was confirmed. These findings support the use of frequency-domain analysis of EMG in future investigations into the corticospinal contribution to control of healthy and disordered human walking. PMID:23740367

  11. Primary Motor Cortex Excitability in Karate Athletes: A Transcranial Magnetic Stimulation Study

    Directory of Open Access Journals (Sweden)

    Vincenzo Monda

    2017-09-01

    Full Text Available Purpose: The mechanisms involved in the coordination of muscle activity are not completely known: to investigate adaptive changes in human motor cortex Transcranial magnetic stimulation (TMS was often used. The sport models are frequently used to study how the training may affect the corticospinal system excitability: Karate represents a valuable sport model for this kind of investigations for its high levels of coordination required to athletes. This study was aimed at examining possible changes in the resting motor threshold (rMT and in the corticospinal response in karate athletes, and at determining whether athletes are characterized by a specific value of rMT.Methods: We recruited 25 right-handed young karate athletes and 25 matched non-athletes. TMS was applied to primary motor cortex (M1. Motor evoked potential (MEP were recorded by two electrodes placed above the first dorsal interosseous (FDI muscle. We considered MEP latencies and amplitudes at rMT, 110% of rMT, and 120% of rMT.Results: The two groups were similar for age (p > 0.05, height (p > 0.05 and body mass (p > 0.05. The TMS had a 70-mm figure-of-eight coil and a maximum output of 2.2 T, placed over the left motor cortex. During the stimulation, a mechanical arm kept the coil tangential to the scalp, with the handle at 45° respect to the midline. The SofTaxic navigator system (E.M.S. Italy, www.emsmedical.net was used in order to correctly identifying and repeating the stimulation for every subject. Compared to non-athletes, athletes showed a lower resting motor threshold (p < 0.001. Furthermore, athletes had a lower MEP latency (p < 0.001 and a higher MEP amplitude (p < 0.001 compared to non-athletes. Moreover, a ROC curve for rMT was found significant (area: 0.907; sensitivity 84%, specificity 76%.Conclusions: As the main finding, the present study showed significant differences in cortical excitability between athletes and non-athletes. The training can improve cortical

  12. A Fault Diagnosis Expert System for a Heavy Motor Used in a Rolling Mill

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A fault diagnosis expert system for a heavy motor used in a rolling mill is established in this paper. The fault diagnosis knowledge base was built, and its knowledge was represented by production rules. The knowledge base includes daily inspection system, brief diagnosis system and precise diagnosis system. A pull-down menu was adopted for the management of the knowledge base. The system can run under the help of expert system development tools. Practical examples show that the expert system can diagnose faults rapidly and precisely.

  13. 77 FR 22637 - Federal Motor Vehicle Safety Standards; Accelerator Control Systems

    Science.gov (United States)

    2012-04-16

    ..., in the case of an electric drive system, attenuate the electric current driving the vehicle... assembly if signals from the pedal position sensor exceed design limits. This could occur without brake... are supplanted by electronic components including sensors, electric motors, a control module,...

  14. Development of the Gross Motor Function Classification System for Cerebral Palsy

    Science.gov (United States)

    Rosenbaum, Peter L.; Palisano, Robert J.; Bartlett, Doreen J.; Galuppi, Barbara E.; Russell, Dianne J.

    2008-01-01

    The Gross Motor Function Classification System (GMFCS) for cerebral palsy has been widely used internationally for clinical, research, and administrative purposes. This paper recounts the ideas and work behind the creation of the GMFCS, reports on the lessons learned, and identifies some philosophical challenges inherent in trying to develop an…

  15. Modeling and Performance Prediction of Induction Motor Drive System for Electric Drive Tracked Vehicles

    Institute of Scientific and Technical Information of China (English)

    CHEN Shu-yong; CHEN Quan-shi; SUN Feng-chun

    2007-01-01

    The principle of rotor flux-orientation vector control on 100/150 kW three-phase AC induction motor for electric drive tracked vehicles is analyzed, and the mathematic model is deduced. The drive system of induction motor is modeled and simulated by Matlab/Simulink. The characteristics of motor and drive system are analyzed and evaluated by practical bench test. The simulation and bench test results show that the model is valid, and the driving control system has constant torque under rated speed, constant torque above rated speed, widely variable speed range and better dynamic characteristics. In order to evaluate the practical applications of high power induction motor driving system in electric drive tracked vehicles, a collaborative simulation based on interface technology of Matlab/Simulink and multi-body dynamic analysis software known as RecurDyn is done, the vehicle performances are predicted in the acceleration time (0-32 km/h) and turning characteristic (v=10 km/h, R=B).

  16. Does (Non-)Meaningful Sensori-Motor Engagement Promote Learning With Animated Physical Systems?

    NARCIS (Netherlands)

    Pouw, Wim T J L; Eielts, Charly; van Gog, Tamara; Zwaan, Rolf A.; Paas, Fred

    2016-01-01

    Previous research indicates that sensori-motor experience with physical systems can have a positive effect on learning. However, it is not clear whether this effect is caused by mere bodily engagement or the intrinsically meaningful information that such interaction affords in performing the learnin

  17. Counteracting Rotor Imbalance in a Bearingless Motor System with Feedforward Control

    Science.gov (United States)

    Kascak, Peter Eugene; Jansen, Ralph H.; Dever, Timothy; Nagorny, Aleksandr; Loparo, Kenneth

    2012-01-01

    In standard motor applications, traditional mechanical bearings represent the most economical approach to rotor suspension. However, in certain high performance applications, rotor suspension without bearing contact is either required or highly beneficial. Such applications include very high speed, extreme environment, or limited maintenance access applications. This paper extends upon a novel bearingless motor concept, in which full five-axis levitation and rotation of the rotor is achieved using two motors with opposing conical air-gaps. By leaving the motors' pole-pairs unconnected, different d-axis flux in each pole-pair is created, generating a flux imbalance which creates lateral force. Note this is approach is different than that used in previous bearingless motors, which use separate windings for levitation and rotation. This paper will examine the use of feedforward control to counteract synchronous whirl caused by rotor imbalance. Experimental results will be presented showing the performance of a prototype bearingless system, which was sized for a high speed flywheel energy storage application, with and without feedforward control.

  18. Anatomical Parameters of tDCS to Modulate the Motor System after Stroke: A Review

    Science.gov (United States)

    Lefebvre, Stephanie; Liew, Sook-Lei

    2017-01-01

    Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method to modulate the local field potential in neural tissue and consequently, cortical excitability. As tDCS is relatively portable, affordable, and accessible, the applications of tDCS to probe brain–behavior connections have rapidly increased in the last 10 years. One of the most promising applications is the use of tDCS to modulate excitability in the motor cortex after stroke and promote motor recovery. However, the results of clinical studies implementing tDCS to modulate motor excitability have been highly variable, with some studies demonstrating that as many as 50% or more of patients fail to show a response to stimulation. Much effort has therefore been dedicated to understand the sources of variability affecting tDCS efficacy. Possible suspects include the placement of the electrodes, task parameters during stimulation, dosing (current amplitude, duration of stimulation, frequency of stimulation), individual states (e.g., anxiety, motivation, attention), and more. In this review, we first briefly review potential sources of variability specific to stroke motor recovery following tDCS. We then examine how the anatomical variability in tDCS placement [e.g., neural target(s) and montages employed] may alter the neuromodulatory effects that tDCS exerts on the post-stroke motor system. PMID:28232816

  19. A high efficiency motor/generator for magnetically suspended flywheel energy storage system

    Science.gov (United States)

    Niemeyer, W. L.; Studer, P.; Kirk, J. A.; Anand, D. K.; Zmood, R. B.

    1989-01-01

    The authors discuss the theory and design of a brushless direct current motor for use in a flywheel energy storage system. The motor design is optimized for a nominal 4.5-in outside diameter operating within a speed range of 33,000-66,000 revolutions per minute with a 140-V maximum supply voltage. The equations which govern the motor's operation are used to compute a series of acceptable design parameter combinations for ideal operation. Engineering tradeoffs are then performed to minimize the irrecoverable energy loss while remaining within the design constraint boundaries. A final integrated structural design whose features allow it to be incorporated with the 500-Wh magnetically suspended flywheel is presented.

  20. High Performance Control of Matrix Converter Fed Induction Motor Drive System

    Institute of Scientific and Technical Information of China (English)

    孙凯; 黄立培; MATSUSE Kouki

    2007-01-01

    Matrix converter fed motor drive is superior to pulse width modulation inverter drives since it not only provides bi-directional power flow, sinusoidal input/output currents, unity input power factor, but also allows a compact design due to the lack of DC-link capacitors for energy storage. In this paper, model and control of matrix converter fed induction motor drive system are analyzed. A combined control strategy is simplified and improved, which realizes space vector pulse width modulation of matrix converter and rotor flux oriented vector control technique for induction motor drive simultaneously. This control strategy combines the advantages of matrix converter with the good drive performance of vector control technique. Experimental results demonstrate the feasibility and effectiveness of the proposed control strategy.

  1. Development of a Mechanical Scanning-type Intravascular Ultrasound System Using a Miniature Ultrasound Motor

    Science.gov (United States)

    Tanabe, Masayuki; Xie, Shangping; Tagawa, Norio; Moriya, Tadashi; Furukawa, Yuji

    2007-07-01

    Intravascular ultrasound (IVUS) plays an important role for the detection of arteriosclerosis, which causes the ischemic heart disease. In mechanical scanning-type IVUS, it is necessary to rotate a transducer or a reflecting mirror. A method that involves rotating the transducer using a torque wire causes image distortion (NURD: non uniform rotation distortion). For a method that involves placing an electromagnetic motor on the tip of an IVUS probe is difficult to miniaturize the probe. Our objectives are to miniaturize the probe (1 mm in diameter, 5 mm in length) and to remove NURD. Therefore, we conducted a study to assess the feasibility of attaining these objectives by constructing a prototype IVUS system, in which an ultrasound motor using a stator in the form of a helical coil (abbreviated as CS-USM: coiled stator-ultrasonic motor) is incorporated, and to clarify problems that need to be solved in constructing the probe.

  2. Precision control system of two-DOF stage with linear ultrasonic motor

    Institute of Scientific and Technical Information of China (English)

    Hanlei ZHANG; Yunlai SHI; Chunsheng ZHAO

    2008-01-01

    Using an appropriate control method, linear ultrasonic motors can be used in applications requiring high position accuracy. In this paper, a closed loop PI control system is designed to achieve high position accu-racy during the control of a two-DOF stage driven by linear ultrasonic motors, Two ultrasonic motors are mounted on the stage to generate motion in two ortho-gonal directions. The PI control algorithm is used to increase the stability and accuracy of position control. The x-axis mover covers 30 mm forward and backward in less than 0.3 s settling time and the y-axis mover in less than 0.4 s. Experimental results denote that the control strategy proposed in this paper appears to have high effi-ciency, quick response, and high accuracy.

  3. Personal experience with narrated events modulates functional connectivity within visual and motor systems during story comprehension.

    Science.gov (United States)

    Chow, Ho Ming; Mar, Raymond A; Xu, Yisheng; Liu, Siyuan; Wagage, Suraji; Braun, Allen R

    2015-04-01

    Past experience of everyday life activities, which forms the basis of our knowledge about the world, greatly affects how we understand stories. Yet, little is known about how this influence is instantiated in the human brain. Here, we used functional magnetic resonance imaging to investigate how past experience facilitates functional connectivity during the comprehension of stories rich in perceptual and motor details. We found that comprehenders' past experience with the scenes and actions described in the narratives selectively modulated functional connectivity between lower- and higher-level areas within the neural systems for visual and motor processing, respectively. These intramodal interactions may play an important role in integrating personal knowledge about a narrated situation with an evolving discourse representation. This study provides empirical evidence consistent with the idea that regions related to visual and motor processing are involved in the reenactment of experience as proposed by theories of embodied cognition.

  4. Intelligent Control Algorithm of PTZ System Driven by Two-DOF Ultrasonic Motor

    Institute of Scientific and Technical Information of China (English)

    Wu Songsen; Leng Xuefei; Jin Jiamei; Wang Bihui; Mao Xingyun

    2015-01-01

    It is difficult for the traditional pan-tilt-zoom (PTZ) system driven by electromagnetic motor to meet the growing demand for video surveillance system .The key challenge is high positioning accuracy ,high dynamic per-formance and miniaturization of the PTZ system .Here a PTZ system driven by two degree-of-freedom obelisk-shaped ultrasonic motor with single stator is presented ,and its intelligent control algorithm is studied .The struc-ture and driving mechanism of the presented PTZ system are analyzed by both simulation and experiment .To solve the complex nonlinear factors ,e .g .time-variation ,dead zone ,the fuzzy PID control algorithm and the variable gain cross-coupled control strategy are combined to improve the control performance .The results show that the proposed algorithm has faster response ,higher precision than traditional control algorithm ,and it also has a good robustness to prevent the effect of interference .

  5. Intelligent Microstepping System for Bipolar Stepper Motor Control with Step and Direction Interface

    Directory of Open Access Journals (Sweden)

    Alexandru Morar

    2010-06-01

    Full Text Available The paper presents a intelligent system for stepper motor control in a microstepping mode, which was designed and performed with a specialized integrated circuit (L292, made by SGS-THOMSON Microelectronics Company. With an interface and an adequate software, L292 circuit can be used as a chopper in 2 or 4 quadrant. The microstepping control system improves the positioning accuracy and eliminates low speed ripple and resonance effects in a stepper motor electric drive. The same microstepping system is ideal for robotics, printers, plotters, X-Y-Z tables and can facilitate the construction of very sophisticated positioning control systems while significantly reducing component cost, board space, design time and systems cost.

  6. Corticospinal Excitability during the Observation of Social Behavior

    Science.gov (United States)

    Bucchioni, Giulia; Cavallo, Andrea; Ippolito, Davide; Marton, Gianluca; Castiello, Umberto

    2013-01-01

    Evidence suggests that the observation of an action induces in the observers an enhancement of motor evoked potentials (MEPs) recorded by the observer's muscles corresponding to those involved in the observed action. Although this is a well-studied phenomenon, it remains still unclear how the viewer's motor facilitation is influenced by the social…

  7. Sensory-evoked and spontaneous gamma and spindle bursts in neonatal rat motor cortex.

    Science.gov (United States)

    An, Shuming; Kilb, Werner; Luhmann, Heiko J

    2014-08-13

    Self-generated neuronal activity originating from subcortical regions drives early spontaneous motor activity, which is a hallmark of the developing sensorimotor system. However, the neural activity patterns and role of primary motor cortex (M1) in these early movements are still unknown. Combining voltage-sensitive dye imaging (VSDI) with simultaneous extracellular multielectrode recordings in postnatal day 3 (P3)-P5 rat primary somatosensory cortex (S1) and M1 in vivo, we observed that tactile forepaw stimulation induced spindle bursts in S1 and gamma and spindle bursts in M1. Approximately 40% of the spontaneous gamma and spindle bursts in M1 were driven by early motor activity, whereas 23.7% of the M1 bursts triggered forepaw movements. Approximately 35% of the M1 bursts were uncorrelated to movements and these bursts had significantly fewer spikes and shorter burst duration. Focal electrical stimulation of layer V neurons in M1 mimicking physiologically relevant 40 Hz gamma or 10 Hz spindle burst activity reliably elicited forepaw movements. We conclude that M1 is already involved in somatosensory information processing during early development. M1 is mainly activated by tactile stimuli triggered by preceding spontaneous movements, which reach M1 via S1. Only a fraction of M1 activity transients trigger motor responses directly. We suggest that both spontaneously occurring and sensory-evoked gamma and spindle bursts in M1 contribute to the maturation of corticospinal and sensorimotor networks required for the refinement of sensorimotor coordination.

  8. Integrated PWM converter/inverter system feeding three-phase induction motor

    Energy Technology Data Exchange (ETDEWEB)

    Bayoumi, E.

    2001-07-01

    The integrated PWM converter/inverter system has the capability of unity power factor, sinusoidal supply current, bi-directional power capabilities and constant dc link voltage. Also, it has the ability to minimize the dc link capacitance. The integrated PWM converter/inverter fed three-phase induction motor consists of two identical PWM converters. One is used to serve as power regulator with unity power factor and constant dc voltage bus, while the other serve as inverter for the induction motor drive. By using the synchronous rotating-frame the current controllers in both the input and the output of the integrated system are characterized by fast current response and low harmonic distortion. The dc link is the intermediate stage between the PWM converter and the PWM inverter. It mainly consists of aluminium electrolytic capacitors, which are normally installed in the system as the energy storage element, but in some applications, such as high power voltage motor drives, the electrolytic capacitor has several drawbacks from the viewpoints of size, weight, cost and reliability. Due to continuous outgassing, the properties of the electrolytic capacitor deteriorate gradually (as time goes by). Hence, the capacitor is the major factor limiting the lifetime of the inverter systems. The aim of this work is to reduce the dc link capacitor size, as it means reduction of the cost and the volume of the converter/inverter systems. The work consists of 8 chapters: Chapter one illustrate the historical overview for the ac/dc/ac fed induction motor drive systems. It describes the benefits of the integrated PWM converter/inverter fed induction motor drive. It classified the integrated PWM converter/inverter systems into two types independent and dependent systems. It demonstrates some ideas for the control algorithms of these types of integrated systems. Chapter two introduces the mathematical model for the PWM converter. It explains the space vector PWM (SVPWM) method for

  9. Structural and functional abnormalities of the motor system in developmental stuttering.

    Science.gov (United States)

    Watkins, Kate E; Smith, Stephen M; Davis, Steve; Howell, Peter

    2008-01-01

    Though stuttering is manifest in its motor characteristics, the cause of stuttering may not relate purely to impairments in the motor system as stuttering frequency is increased by linguistic factors, such as syntactic complexity and length of utterance, and decreased by changes in perception, such as masking or altering auditory feedback. Using functional and diffusion imaging, we examined brain structure and function in the motor and language areas in a group of young people who stutter. During speech production, irrespective of fluency or auditory feedback, the people who stuttered showed overactivity relative to controls in the anterior insula, cerebellum and midbrain bilaterally and underactivity in the ventral premotor, Rolandic opercular and sensorimotor cortex bilaterally and Heschl's gyrus on the left. These results are consistent with a recent meta-analysis of functional imaging studies in developmental stuttering. Two additional findings emerged from our study. First, we found overactivity in the midbrain, which was at the level of the substantia nigra and extended to the pedunculopontine nucleus, red nucleus and subthalamic nucleus. This overactivity is consistent with suggestions in previous studies of abnormal function of the basal ganglia or excessive dopamine in people who stutter. Second, we found underactivity of the cortical motor and premotor areas associated with articulation and speech production. Analysis of the diffusion data revealed that the integrity of the white matter underlying the underactive areas in ventral premotor cortex was reduced in people who stutter. The white matter tracts in this area via connections with posterior superior temporal and inferior parietal cortex provide a substrate for the integration of articulatory planning and sensory feedback, and via connections with primary motor cortex, a substrate for execution of articulatory movements. Our data support the conclusion that stuttering is a disorder related primarily

  10. The effects of low- and high-frequency repetitive TMS on the input/output properties of the human corticospinal pathway.

    Science.gov (United States)

    Houdayer, E; Degardin, A; Cassim, F; Bocquillon, P; Derambure, P; Devanne, H

    2008-05-01

    The objective of this study was to characterize the effects of various parameters (notably the frequency and intensity) of repetitive transcranial magnetic stimulation (rTMS) applied over the primary motor (M1) and premotor (PMC) cortices on the excitability of the first dorsalis interosseus (FDI) corticospinal pathway. To this end, we applied a comprehensive input-output analysis after fitting the experimental results to a sigmoidal function. Twenty-six healthy subjects participated in the experiments. Repetitive TMS was applied either over M1 or PMC at 1 Hz (LF) for 30 min (1,800 pulses) or at 20 Hz (HF) for 20 min (1,600 pulses). In the HF condition, the TMS intensity was set to 90% (HF(90)) of the FDI's resting motor threshold (RMT). In the LF condition, the TMS intensity was set to either 90% (LF(90)) or 115% (LF(115)) of the RMT. The FDI input/output (I/O) curve was measured on both sides of the body before rTMS (the Pre session) and then during two Post sessions. For each subject, the I/O curves (i.e., the integral of the FDI motor-evoked potential (MEP) vs. stimulus intensity) were fitted using a Boltzmann sigmoidal function. The graph's maximum slope, S (50) and plateau value were then compared between Pre and Post sessions. LF(115) over M1 increased the slope of the FDI I/O curve but did not change the S (50) and plateau value. This also suggested an increase in the RMT. HF(90) led to a more complex effect, with an increase in the slope and a decrease in the S (50) and plateau value. We did not see a cross effect on the homologous FDI corticospinal pathway, and only PMC LF(90) had an effect on ipsilateral corticospinal excitability. Our results suggest that rTMS may exert a more complex influence on cortical network excitability than is usually reported (i.e. simple inhibitory or facilitatory effects). Analysis of the fitted stimulus response curve indicates a dichotomous influence of both low- and high-frequency rTMS on M1 cortical excitability; this may

  11. System and method for monitoring and controlling stator winding temperature in a de-energized AC motor

    Science.gov (United States)

    Lu, Bin; Luebke, Charles John; Habetler, Thomas G.; Zhang, Pinjia; Becker, Scott K.

    2011-12-27

    A system and method for measuring and controlling stator winding temperature in an AC motor while idling is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of a multi-phase AC motor. The circuit further includes a plurality of switching devices to control current flow and terminal voltages in the multi-phase AC motor and a controller connected to the circuit. The controller is configured to activate the plurality of switching devices to create a DC signal in an output of the motor control device corresponding to an input to the multi-phase AC motor, determine or estimate a stator winding resistance of the multi-phase AC motor based on the DC signal, and estimate a stator temperature from the stator winding resistance. Temperature can then be controlled and regulated by DC injection into the stator windings.

  12. Vectorial Command of Induction Motor Pumping System Supplied by a Photovoltaic Generator

    Science.gov (United States)

    Makhlouf, Messaoud; Messai, Feyrouz; Benalla, Hocine

    2011-01-01

    With the continuous decrease of the cost of solar cells, there is an increasing interest and needs in photovoltaic (PV) system applications following standard of living improvements. Water pumping system powered by solar-cell generators are one of the most important applications. The fluctuation of solar energy on one hand, and the necessity to optimise available solar energy on the other, it is useful to develop new efficient and flexible modes to control motors that entrain the pump. A vectorial control of an asynchronous motor fed by a photovoltaic system is proposed. This paper investigates a photovoltaic-electro mechanic chain, composed of a PV generator, DC-AC converter, a vector controlled induction motor and centrifugal pump. The PV generator is forced to operate at its maximum power point by using an appropriate search algorithm integrated in the vector control. The optimization is realized without need to adding a DC-DC converter to the chain. The motor supply is also ensured in all insolation conditions. Simulation results show the effectiveness and feasibility of such an approach.

  13. Responses of the human motor system to observing actions across species: A transcranial magnetic stimulation study.

    Science.gov (United States)

    White, Nicole C; Reid, Connor; Welsh, Timothy N

    2014-10-22

    Ample evidence suggests that the role of the mirror neuron system (MNS) in monkeys is to represent the meaning of actions. The MNS becomes active in monkeys during execution, observation, and auditory experience of meaningful, object-oriented actions, suggesting that these cells represent the same action based on a variety of cues. The present study sought to determine whether the human motor system, part of the putative human MNS, similarly represents and reflects the meaning of actions rather than simply the mechanics of the actions. To this end, transcranial magnetic stimulation (TMS) of primary motor cortex was used to generate motor-evoked potentials (MEPs) from muscles involved in grasping while participants viewed object-oriented grasping actions performed by either a human, an elephant, a rat, or a body-less robotic arm. The analysis of MEP amplitudes suggested that activity in primary motor cortex during action observation was greatest during observation of the grasping actions of the rat and elephant, and smallest for the human and robotic arm. Based on these data, we conclude that the human action observation system can represent actions executed by non-human animals and shows sensitivity to species-specific differences in action mechanics.

  14. Identification and adaptive neural network control of a DC motor system with dead-zone characteristics.