Current superimposition variable flux reluctance motor with 8 salient poles

Science.gov (United States)

Takahara, Kazuaki; Hirata, Katsuhiro; Niguchi, Noboru; Kohara, Akira

2017-12-01

We propose a current superimposition variable flux reluctance motor for a traction motor of electric vehicles and hybrid electric vehicles, which consists of 10 salient poles in the rotor and 12 slots in the stator. However, iron losses of this motor in high rotation speed ranges is large because the number of salient poles is large. In this paper, we propose a current superimposition variable flux reluctance motor that consists of 8 salient poles and 12 slots. The characteristics of the 10-pole-12-slot and 8-pole-12-slot current superimposition variable flux reluctance motors are compared using finite element analysis under vector control.

Current superimposition variable flux reluctance motor with 8 salient poles

Directory of Open Access Journals (Sweden)

Takahara Kazuaki

2017-12-01

Full Text Available We propose a current superimposition variable flux reluctance motor for a traction motor of electric vehicles and hybrid electric vehicles, which consists of 10 salient poles in the rotor and 12 slots in the stator. However, iron losses of this motor in high rotation speed ranges is large because the number of salient poles is large. In this paper, we propose a current superimposition variable flux reluctance motor that consists of 8 salient poles and 12 slots. The characteristics of the 10-pole-12-slot and 8-pole-12-slot current superimposition variable flux reluctance motors are compared using finite element analysis under vector control.

Impairments of Motor Function While Multitasking in HIV

Directory of Open Access Journals (Sweden)

Cherie L. Marvel

2017-04-01

Full Text Available Human immunodeficiency virus (HIV became a treatable illness with the introduction of combination antiretroviral therapy (CART. As a result, patients with regular access to CART are expected to live decades with HIV. Long-term HIV infection presents unique challenges, including neurocognitive impairments defined by three major stages of HIV-associated neurocognitive disorders (HAND. The current investigation aimed to study cognitive and motor impairments in HIV using a novel multitasking paradigm. Unlike current standard measures of cognitive and motor performance in HIV, multitasking increases real-world validity by mimicking the dual motor and cognitive demands that are part of daily professional and personal settings (e.g., driving, typing and writing. Moreover, multitask assessments can unmask compensatory mechanisms, normally used under single task conditions, to maintain performance. This investigation revealed that HIV+ participants were impaired on the motor component of the multitask, while cognitive performance was spared. A patient-specific positive interaction between motor performance and working memory recall was driven by poor HIV+ multitaskers. Surprisingly, HAND stage did not correspond with multitask performance and a variety of commonly used assessments indicated normal motor function among HIV+ participants with poor motor performance during the experimental task. These results support the use of multitasks to reveal otherwise hidden impairment in chronic HIV by expanding the sensitivity of clinical assessments used to determine HAND stage. Future studies should examine the capability of multitasks to predict performance in personal, professional and health-related behaviors and prognosis of patients living with chronic HIV.

Motor network structure and function are associated with motor performance in Huntington's disease.

Science.gov (United States)

Müller, Hans-Peter; Gorges, Martin; Grön, Georg; Kassubek, Jan; Landwehrmeyer, G Bernhard; Süßmuth, Sigurd D; Wolf, Robert Christian; Orth, Michael

2016-03-01

In Huntington's disease, the relationship of brain structure, brain function and clinical measures remains incompletely understood. We asked how sensory-motor network brain structure and neural activity relate to each other and to motor performance. Thirty-four early stage HD and 32 age- and sex-matched healthy control participants underwent structural magnetic resonance imaging (MRI), diffusion tensor, and intrinsic functional connectivity MRI. Diffusivity patterns were assessed in the cortico-spinal tract and the thalamus-somatosensory cortex tract. For the motor network connectivity analyses the dominant M1 motor cortex region and for the basal ganglia-thalamic network the thalamus were used as seeds. Region to region structural and functional connectivity was examined between thalamus and somatosensory cortex. Fractional anisotropy (FA) was higher in HD than controls in the basal ganglia, and lower in the external and internal capsule, in the thalamus, and in subcortical white matter. Between-group axial and radial diffusivity differences were more prominent than differences in FA, and correlated with motor performance. Within the motor network, the insula was less connected in HD than in controls, with the degree of connection correlating with motor scores. The basal ganglia-thalamic network's connectivity differed in the insula and basal ganglia. Tract specific white matter diffusivity and functional connectivity were not correlated. In HD sensory-motor white matter organization and functional connectivity in a motor network were independently associated with motor performance. The lack of tract-specific association of structure and function suggests that functional adaptation to structural loss differs between participants.

Torque harmonics of an asynchronous motor supplied by a voltage- or current-sourced inverter quasi-square operation

Energy Technology Data Exchange (ETDEWEB)

Kyyrae, J. [Helsinki University of Technology, Institute of Intelligent Power Electronics, Espoo (Finland)

1997-12-31

Voltage- and current-sourced dc-ac converters operating in quasi-square area are compared. Their characteristics are calculated with switching vector, which is space-vector of switching functions. When the load is an asynchronous motor various analytical equations, including torque, are calculated efficiently. Motor current and torque approximations are compared with the simulated ones. (orig.) 6 refs.

Effects of gross motor function and manual function levels on performance-based ADL motor skills of children with spastic cerebral palsy

OpenAIRE

Park, Myoung-Ok

2017-01-01

[Purpose] The purpose of this study was to determine effects of Gross Motor Function Classification System and Manual Ability Classification System levels on performance-based motor skills of children with spastic cerebral palsy. [Subjects and Methods] Twenty-three children with cerebral palsy were included. The Assessment of Motor and Process Skills was used to evaluate performance-based motor skills in daily life. Gross motor function was assessed using Gross Motor Function Classification S...

Starting characteristics of direct current motors powered by solar cells

Science.gov (United States)

Singer, S.; Appelbaum, J.

1989-01-01

Direct current motors are used in photovoltaic systems. Important characteristics of electric motors are the starting to rated current and torque ratios. These ratios are dictated by the size of the solar cell array and are different for the various dc motor types. Discussed here is the calculation of the starting to rated current ratio and starting to rated torque ratio of the permanent magnet, and series and shunt excited motors when powered by solar cells for two cases: with and without a maximum-power-point-tracker (MPPT) included in the system. Comparing these two cases, one gets a torque magnification of about 3 for the permanent magnet motor and about 7 for other motor types. The calculation of the torques may assist the PV system designer to determine whether or not to include an MPPT in the system.

In Vivo Neuromechanics: Decoding Causal Motor Neuron Behavior with Resulting Musculoskeletal Function.

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Sartori, Massimo; Yavuz, Utku Ş; Farina, Dario

2017-10-18

Human motor function emerges from the interaction between the neuromuscular and the musculoskeletal systems. Despite the knowledge of the mechanisms underlying neural and mechanical functions, there is no relevant understanding of the neuro-mechanical interplay in the neuro-musculo-skeletal system. This currently represents the major challenge to the understanding of human movement. We address this challenge by proposing a paradigm for investigating spinal motor neuron contribution to skeletal joint mechanical function in the intact human in vivo. We employ multi-muscle spatial sampling and deconvolution of high-density fiber electrical activity to decode accurate α-motor neuron discharges across five lumbosacral segments in the human spinal cord. We use complete α-motor neuron discharge series to drive forward subject-specific models of the musculoskeletal system in open-loop with no corrective feedback. We perform validation tests where mechanical moments are estimated with no knowledge of reference data over unseen conditions. This enables accurate blinded estimation of ankle function purely from motor neuron information. Remarkably, this enables observing causal associations between spinal motor neuron activity and joint moment control. We provide a new class of neural data-driven musculoskeletal modeling formulations for bridging between movement neural and mechanical levels in vivo with implications for understanding motor physiology, pathology, and recovery.

Transcranial direct current stimulation of the primary motor cortex improves word-retrieval in older adults.

Science.gov (United States)

Meinzer, Marcus; Lindenberg, Robert; Sieg, Mira M; Nachtigall, Laura; Ulm, Lena; Flöel, Agnes

2014-01-01

Language facilitation by transcranial direct current stimulation (tDCS) in healthy individuals has generated hope that tDCS may also allow improving language impairment after stroke (aphasia). However, current stimulation protocols have yielded variable results and may require identification of residual language cortex using functional magnetic resonance imaging (fMRI), which complicates incorporation into clinical practice. Based on previous behavioral studies that demonstrated improved language processing by motor system pre-activation, the present study assessed whether tDCS administered to the primary motor cortex (M1) can enhance language functions. This proof-of-concept study employed a sham-tDCS controlled, cross-over, within-subject design and assessed the impact of unilateral excitatory (anodal) and bihemispheric (dual) tDCS in 18 healthy older adults during semantic word-retrieval and motor speech tasks. Simultaneous fMRI scrutinized the neural mechanisms underlying tDCS effects. Both active tDCS conditions significantly improved word-retrieval compared to sham-tDCS. The direct comparison of activity elicited by word-retrieval vs. motor-speech trials revealed bilateral frontal activity increases during both anodal- and dual-tDCS compared to sham-tDCS. This effect was driven by more pronounced deactivation of frontal regions during the motor-speech task, while activity during word-retrieval trials was unaffected by the stimulation. No effects were found in M1 and secondary motor regions. Our results show that tDCS administered to M1 can improve word-retrieval in healthy individuals, thereby providing a rationale to explore whether M1-tDCS may offer a novel approach to improve language functions in aphasia. Functional magnetic resonance imaging revealed neural facilitation specifically during motor speech trials, which may have reduced switching costs between the overlapping neural systems for lexical retrieval and speech processing, thereby resulting in

Alternating-Current Motor Drive for Electric Vehicles

Science.gov (United States)

Krauthamer, S.; Rippel, W. E.

1982-01-01

New electric drive controls speed of a polyphase as motor by varying frequency of inverter output. Closed-loop current-sensing circuit automatically adjusts frequency of voltage-controlled oscillator that controls inverter frequency, to limit starting and accelerating surges. Efficient inverter and ac motor would give electric vehicles extra miles per battery charge.

An Examination of the Relationship between Motor Coordination and Executive Functions in Adolescents

Science.gov (United States)

Rigoli, Daniela; Piek, Jan P.; Kane, Robert; Oosterlaan, Jaap

2012-01-01

Aim: Research suggests important links between motor coordination and executive functions. The current study examined whether motor coordination predicts working memory, inhibition, and switching performance, extending previous research by accounting for attention-deficit-hyperactivity disorder (ADHD) symptomatology and other confounding factors,…

Motor function domains in alternating hemiplegia of childhood.

Science.gov (United States)

Masoud, Melanie; Gordon, Kelly; Hall, Amanda; Jasien, Joan; Lardinois, Kara; Uchitel, Julie; Mclean, Melissa; Prange, Lyndsey; Wuchich, Jeffrey; Mikati, Mohamad A

2017-08-01

To characterize motor function profiles in alternating hemiplegia of childhood, and to investigate interrelationships between these domains and with age. We studied a cohort of 23 patients (9 males, 14 females; mean age 9y 4mo, range 4mo-43y) who underwent standardized tests to assess gross motor, upper extremity motor control, motor speech, and dysphagia functions. Gross Motor Function Classification System (GMFCS), Gross Motor Function Measure-88 (GMFM-88), Manual Ability Classification System (MACS), and Revised Melbourne Assessment (MA2) scales manifested predominantly mild impairments; motor speech, moderate to severe; Modified Dysphagia Outcome and Severity Scale (M-DOSS), mild-to moderate deficits. GMFCS correlated with GMFM-88 scores (Pearson's correlation, p=0.002), MACS (p=0.038), and MA2 fluency (p=0.005) and accuracy (p=0.038) scores. GMFCS did not correlate with motor speech (p=0.399), MA2 dexterity (p=0.247), range of motion (p=0.063), or M-DOSS (p=0.856). Motor speech was more severely impaired than the GMFCS (p<0.013). There was no correlation between any of the assessment tools and age (p=0.210-0.798). Our data establish a detailed profile of motor function in alternating hemiplegia of childhood, argue against the presence of worse motor function in older patients, identify tools helpful in evaluating this population, and identify oropharyngeal function as the more severely affected domain, suggesting that brain areas controlling this function are more affected than others. © 2017 Mac Keith Press.

Soft commutated direct current motor [summary of proposed paper

Energy Technology Data Exchange (ETDEWEB)

Hsu, John S.

1998-10-22

A novel soft commutated direct current (DC) motor is introduced. The current of the commutated coil is intentionally drained before the brush disconnects the coil. This prevents the spark generation that normally occurs in conventional DC motors. A similar principle can be applied for DC generators.

Motor control for a brushless DC motor

Science.gov (United States)

Peterson, William J. (Inventor); Faulkner, Dennis T. (Inventor)

1985-01-01

This invention relates to a motor control system for a brushless DC motor having an inverter responsively coupled to the motor control system and in power transmitting relationship to the motor. The motor control system includes a motor rotor speed detecting unit that provides a pulsed waveform signal proportional to rotor speed. This pulsed waveform signal is delivered to the inverter to thereby cause an inverter fundamental current waveform output to the motor to be switched at a rate proportional to said rotor speed. In addition, the fundamental current waveform is also pulse width modulated at a rate proportional to the rotor speed. A fundamental current waveform phase advance circuit is controllingly coupled to the inverter. The phase advance circuit is coupled to receive the pulsed waveform signal from the motor rotor speed detecting unit and phase advance the pulsed waveform signal as a predetermined function of motor speed to thereby cause the fundamental current waveform to be advanced and thereby compensate for fundamental current waveform lag due to motor winding reactance which allows the motor to operate at higher speeds than the motor is rated while providing optimal torque and therefore increased efficiency.

PROTECTION OF HOUSEHOLD APPLIANCES INDUCTION MOTORS AGAINST OVERCURRENT TAKING INTO ACCOUNT NONLINEAR DISTORTION OF PHASE CURRENT

Directory of Open Access Journals (Sweden)

A.G. Sereda

2015-06-01

Full Text Available Purpose. Theoretical justification and engineering of induction motors heat protection method from overload currents taking into account nonlinear distortion of the phase current and implementation as a microprocessor device functioning algorithm. Methodology. To solve the problem used the theory of the representing complex harmonic oscillations analog signals expansion into the oscillation spectrum forming elementary harmonic components in order to compare their properties by applying the theory of discrete signals and systems, as well as methods of spectral analysis and discrete signals filtering. The harmonic analysis versatility is that any periodic signal may be synthesized from harmonic oscillation of certain amplitude, frequency and initial phase. A mathematical model for determining the phase current harmonic content of power supply networks with isolated neutral and non-linear loads types and, as a consequence, the distortion of sinusoidal phase current change is developed by multiplying the analog current in time dependency on the grate delta-function with different sampling intervals, in which the use of simple and widely used in relay protection units, in particular electronic overcurrent relays, mathematical operations of integration squares instantaneous current allows the most in harmony with the mathematical tools to build other network protection types. Findings. The necessity to increase the sensitivity of the induction motors heat protection from overload currents taking into account nonlinear distortion of the phase currents is proved. By nonlinear distortion harmonic analysis of the phase currents the motor protection reliability increasing provided by taking into account the higher harmonic components of the phase currents, which causes to additional losses and heating of the stator winding. It uses the simplest and widely used in protective relaying mathematical apparatus determining of most significant higher harmonics

Motor unit recruitment by size does not provide functional advantages for motor performance.

Science.gov (United States)

Dideriksen, Jakob L; Farina, Dario

2013-12-15

It is commonly assumed that the orderly recruitment of motor units by size provides a functional advantage for the performance of movements compared with a random recruitment order. On the other hand, the excitability of a motor neuron depends on its size and this is intrinsically linked to its innervation number. A range of innervation numbers among motor neurons corresponds to a range of sizes and thus to a range of excitabilities ordered by size. Therefore, if the excitation drive is similar among motor neurons, the recruitment by size is inevitably due to the intrinsic properties of motor neurons and may not have arisen to meet functional demands. In this view, we tested the assumption that orderly recruitment is necessarily beneficial by determining if this type of recruitment produces optimal motor output. Using evolutionary algorithms and without any a priori assumptions, the parameters of neuromuscular models were optimized with respect to several criteria for motor performance. Interestingly, the optimized model parameters matched well known neuromuscular properties, but none of the optimization criteria determined a consistent recruitment order by size unless this was imposed by an association between motor neuron size and excitability. Further, when the association between size and excitability was imposed, the resultant model of recruitment did not improve the motor performance with respect to the absence of orderly recruitment. A consistent observation was that optimal solutions for a variety of criteria of motor performance always required a broad range of innervation numbers in the population of motor neurons, skewed towards the small values. These results indicate that orderly recruitment of motor units in itself does not provide substantial functional advantages for motor control. Rather, the reason for its near-universal presence in human movements is that motor functions are optimized by a broad range of innervation numbers.

Inhibition linearizes firing rate responses in human motor units: implications for the role of persistent inward currents.

Science.gov (United States)

Revill, Ann L; Fuglevand, Andrew J

2017-01-01

Motor neurons are the output neurons of the central nervous system and are responsible for controlling muscle contraction. When initially activated during voluntary contraction, firing rates of motor neurons increase steeply but then level out at modest rates. Activation of an intrinsic source of excitatory current at recruitment onset may underlie the initial steep increase in firing rate in motor neurons. We attempted to disable this intrinsic excitatory current by artificially activating an inhibitory reflex. When motor neuron activity was recorded while the inhibitory reflex was engaged, firing rates no longer increased steeply, suggesting that the intrinsic excitatory current was probably responsible for the initial sharp rise in motor neuron firing rate. During graded isometric contractions, motor unit (MU) firing rates increase steeply upon recruitment but then level off at modest rates even though muscle force continues to increase. The mechanisms underlying such firing behaviour are not known although activation of persistent inward currents (PICs) might be involved. PICs are intrinsic, voltage-dependent currents that activate strongly when motor neurons (MNs) are first recruited. Such activation might cause a sharp escalation in depolarizing current and underlie the steep initial rise in MU firing rate. Because PICs can be disabled with synaptic inhibition, we hypothesized that artificial activation of an inhibitory pathway might curb this initial steep rise in firing rate. To test this, human subjects performed slow triangular ramp contractions of the ankle dorsiflexors in the absence and presence of tonic synaptic inhibition delivered to tibialis anterior (TA) MNs by sural nerve stimulation. Firing rate profiles (expressed as a function of contraction force) of TA MUs recorded during these tasks were compared for control and stimulation conditions. Under control conditions, during the ascending phase of the triangular contractions, 93% of the firing

Current direction-dependent modulation of human hand motor function by intermittent theta burst stimulation (iTBS).

Science.gov (United States)

Shirota, Yuichiro; Dhaka, Suman; Paulus, Walter; Sommer, Martin

2017-05-22

Transcranial magnetic stimulation (TMS) with different current directions can activate different sets of neurons. Current direction can also affect the results of repetitive TMS. To test the influence of uni-directional intermittent theta burst stimulation (iTBS) using different current directions, namely posteroanterior (PA) and anteroposterior (AP), on motor behaviour. In a cross-over design, PA- and AP-iTBS was applied over the left primary motor cortex in 19 healthy, right-handed volunteers. Performance of a finger-tapping task was recorded before and 0, 10, 20, and 30min after the iTBS. The task was conducted with the right and left hands separately at each time point. As a control, AP-iTBS with reduced intensity was applied to 14 participants in a separate session (AP weak condition). The finger-tapping count with the left hand was decreased after PA-iTBS. Neither AP- nor AP weak -iTBS altered the performance. Current direction had a significant impact on the after-effects of iTBS. Copyright © 2017 Elsevier B.V. All rights reserved.

Current and investigational non-dopaminergic agents for management of motor symptoms (including motor complications) in Parkinson's disease.

Science.gov (United States)

Müller, Thomas

2017-10-01

Parkinson's disease is characterized by a heterogeneous combination of motor and non motor symptoms. The nigrostriatal dopamine deficit is one of its essential pathophysiologic features. Areas covered: This invited narrative review provides an overlook over current available and future promising non dopaminergic therapeutics to modulate altered dopaminergic neurotransmission in Parkinson's disease. Current research strategies aim to proof clinical efficacy by amelioration of motor symptoms and preponderant levodopa related movement fluctuations. These so-called motor complications are characterized by involuntary movements as a result of an overstimulation of the nigrostriatal dopaminergic system or by temporary recurrence of motor symptoms, when beneficial effects of dopamine substituting drugs vane. Expert opinion: Non dopaminergic modulation of dopamine replacement is currently mostly investigated in well defined and selected patients with motor complications to get approval. However, the world of daily maintenance of patients with its individually adapted, so-called personalised, therapy will determine the real value of these therapeutics. Here the clinical experience of the treating neurologists and the courage to use unconventional drug combinations are essential preconditions for successful treatments of motor and associated non motor complications in cooperation with the patients and their care giving surroundings.

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.

Transcranial electric stimulation for intraoperative motor evoked potential monitoring: dependence of required stimulation current on interstimulus interval value.

Science.gov (United States)

Joksimovic, Boban; Szelenyi, Andrea; Seifert, Volker; Damjanovic, Aleksandar; Damjanovic, Aleksandra; Rasulic, Lukas

2015-05-01

To evaluate the relationship between stimulus intensity by constant current transcranial electric stimulation and interstimulus interval (ISI) for eliciting muscle motor evoked potentials (MEPs) in three different hand muscles and the tibialis anterior muscles. We tested intraoperatively different monophasic constant current pulses and ISIs in 22 patients with clinically normal motor function. Motor thresholds of contralateral muscle MEPs were determined at 0.5 milliseconds (ms) pulse duration and ISIs of 1, 2, 3, 4, 5, and 10 ms using a train of 2, 3, and 5 monophasic constant current pulses of 62 to 104 mA before craniotomy and after closure of the dura mater. The lowest stimulation threshold to elicit MEPs in the examined muscles was achieved with a train of 5 pulses (ISI: 3 ms) before craniotomy, which was statistically significant compared with 2 pulses (ISI: 3 ms) as well as 3 pulses (ISIs: 3 and 10 ms). An ISI of 3 ms gave the lowest motor thresholds with statistical significance compared with the ISIs of 4 ms (2 pulses) and of 1 ms (3 pulses). All current intensity (mA) and ISI (ms) relationship graphs had a trend of the exponential function as y = a + bx + c ρ (x), where y is intensity (mA) and x is ISI (ms). The minimum of the function was determined for each patient and each muscle. The difference was statistically significant between 3 and 5 pulses before craniotomy and between 3 and 5 pulses and 2 and 5 pulses after closure of the dura mater. In adult neurosurgical patients with a normal motor status, a train of 5 pulses and an ISI of 3 ms provide the lowest motor thresholds. We provided evidence of the dependence of required stimulation current on ISI. Georg Thieme Verlag KG Stuttgart · New York.

Transcranial direct current stimulation of the primary motor cortex improves word-retrieval in older adults.

Directory of Open Access Journals (Sweden)

Marcus eMeinzer

2014-09-01

Full Text Available Language facilitation by transcranial direct current stimulation (tDCS in healthy individuals has generated hope that tDCS may also allow improving language impairment after stroke (aphasia. However, current stimulation protocols have yielded variable results and may require identification of residual language cortex using functional magnetic resonance imaging (fMRI, which complicates incorporation into clinical practice. Based on previous behavioral studies that demonstrated improved language processing by motor system pre-activation, the present study assessed whether tDCS administered to the primary motor cortex (M1 can enhance language functions.This proof-of-concept study employed a sham-tDCS controlled, cross-over, within-subject design and assessed the impact of unilateral excitatory (anodal and bihemispheric (dual tDCS in eighteen healthy older adults during semantic word-retrieval and motor speech tasks. Simultaneous fMRI scrutinized the neural mechanisms underlying tDCS effects.Both active tDCS conditions significantly improved word-retrieval compared to sham-tDCS. The direct comparison of activity elicited by word-retrieval vs. motor-speech trials revealed bilateral frontal activity increases during both anodal- and dual-tDCS compared to sham-tDCS. This effect was driven by more pronounced deactivation of frontal regions during the motor-speech task, while activity during word-retrieval trials was unaffected by the stimulation. No effects were found in M1 and secondary motor regions.Our results show that tDCS administered to M1 can improve word-retrieval in healthy individuals, thereby providing a rationale to explore whether M1-tDCS may offer a novel approach to improve language functions in aphasia. fMRI revealed neural facilitation specifically during motor speech trials, which may have reduced switching costs between the overlapping neural systems for lexical retrieval and speech processing, thereby resulting in improved

Association Between Gross-Motor and Executive Function Depends on Age and Motor Task Complexity

DEFF Research Database (Denmark)

Spedden, Meaghan E; Malling, Anne Sofie B; Andersen, Ken K

2017-01-01

The objective was to examine associations between motor and executive function across the adult lifespan and to investigate the role of motor complexity in these associations. Young, middle-aged and older adults (n = 82; 19-83y) performed two gross-motor tasks with different levels of complexity...... and a Stroop-like computer task. Performance was decreased in older adults. The association between motor and cognitive performance was significant for older adults in the complex motor task (p = 0.03, rs = -0.41), whereas no significant associations were found for young or middle-aged groups, suggesting...... that the link between gross-motor and executive function emerges with age and depends on motor complexity....

Optimal current waveforms for brushless permanent magnet motors

Science.gov (United States)

Moehle, Nicholas; Boyd, Stephen

2015-07-01

In this paper, we give energy-optimal current waveforms for a permanent magnet synchronous motor that result in a desired average torque. Our formulation generalises previous work by including a general back-electromotive force (EMF) wave shape, voltage and current limits, an arbitrary phase winding connection, a simple eddy current loss model, and a trade-off between power loss and torque ripple. Determining the optimal current waveforms requires solving a small convex optimisation problem. We show how to use the alternating direction method of multipliers to find the optimal current in milliseconds or hundreds of microseconds, depending on the processor used, which allows the possibility of generating optimal waveforms in real time. This allows us to adapt in real time to changes in the operating requirements or in the model, such as a change in resistance with winding temperature, or even gross changes like the failure of one winding. Suboptimal waveforms are available in tens or hundreds of microseconds, allowing for quick response after abrupt changes in the desired torque. We demonstrate our approach on a simple numerical example, in which we give the optimal waveforms for a motor with a sinusoidal back-EMF, and for a motor with a more complicated, nonsinusoidal waveform, in both the constant-torque region and constant-power region.

Olfaction Is Related to Motor Function in Older Adults.

Science.gov (United States)

Tian, Qu; Resnick, Susan M; Studenski, Stephanie A

2017-08-01

Among older adults, both olfaction and motor function predict future cognitive decline and dementia, suggesting potential shared causal pathways. However, it is not known whether olfactory and motor function are independently related in late life. We assessed cross-sectional associations of olfaction with motor and cognitive function, using concurrent data on olfactory function, mobility, balance, fine motor function, manual dexterity, and cognition in 163 Baltimore Longitudinal Study of Aging participants aged 60 and older without common neurological diseases (n = 114 with available cognitive data). Using multiple linear regression, we adjusted for age, sex, race, smoking history, height, and weight for mobility and balance, and education for cognition. We used multiple linear regression to test whether olfaction-motor associations were independent of cognition and depressive symptoms. Olfactory scores were significantly associated with mobility (usual gait speed, rapid gait speed, 400-m walk time, and Health ABC Physical Performance Battery score), balance, fine motor function, and manual dexterity (all p function is associated with mobility, balance, fine motor function, and manual dexterity, and independent of cognitive function, with challenging upper and lower extremity motor function tasks. Longitudinal studies are needed to determine if olfactory performance predicts future mobility and functional decline. Published by Oxford University Press on behalf of The Gerontological Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Enhanced motor learning with bilateral transcranial direct current stimulation: Impact of polarity or current flow direction?

Science.gov (United States)

Naros, Georgios; Geyer, Marc; Koch, Susanne; Mayr, Lena; Ellinger, Tabea; Grimm, Florian; Gharabaghi, Alireza

2016-04-01

Bilateral transcranial direct current stimulation (TDCS) is superior to unilateral TDCS when targeting motor learning. This effect could be related to either the current flow direction or additive polarity-specific effects on each hemisphere. This sham-controlled randomized study included fifty right-handed healthy subjects in a parallel-group design who performed an exoskeleton-based motor task of the proximal left arm on three consecutive days. Prior to training, we applied either sham, right anodal (a-TDCS), left cathodal (c-TDCS), concurrent a-TDCS and c-TDCS with two independent current sources and return electrodes (double source (ds)-TDCS) or classical bilateral stimulation (bi-TDCS). Motor performance improved over time for both unilateral (a-TDCS, c-TDCS) and bilateral (bi-TDCS, ds-TDCS) TDCS montages. However, only the two bilateral paradigms led to an improvement of the final motor performance at the end of the training period as compared to the sham condition. There was no difference between the two bilateral stimulation conditions (bi-TDCS, ds-TDCS). Bilateral TDCS is more effective than unilateral stimulation due to its polarity-specific effects on each hemisphere rather than due to its current flow direction. This study is the first systematic evaluation of stimulation polarity and current flow direction of bi-hemispheric motor cortex TDCS on motor learning of proximal upper limb muscles. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Speed Control Analysis of Brushless DC Motor Based on Maximum Amplitude DC Current Feedback

Directory of Open Access Journals (Sweden)

Hassan M.A.A.

2014-07-01

Full Text Available This paper describes an approach to develop accurate and simple current controlled modulation technique for brushless DC (BLDC motor drive. The approach is applied to control phase current based on generation of quasi-square wave current by using only one current controller for the three phases. Unlike the vector control method which is complicated to be implemented, this simple current modulation technique presents advantages such as phase currents are kept in balance and the current is controlled through only one dc signal which represent maximum amplitude value of trapezoidal current (Imax. This technique is performed with Proportional Integral (PI control algorithm and triangular carrier comparison method to generate Pulse Width Modulation (PWM signal. In addition, the PI speed controller is incorporated with the current controller to perform desirable speed operation of non-overshoot response. The performance and functionality of the BLDC motor driver are verified via simulation by using MATLAB/SIMULINK. The simulation results show the developed control system performs desirable speed operation of non-overshoot and good current waveforms.

Does transcranial direct current stimulation affect the learning of a fine sequential hand motor skill with motor imagery?

NARCIS (Netherlands)

Sobierajewicz, Jagna; Jaskowski, Wojciech; van der Lubbe, Robert Henricus Johannes

2017-01-01

Learning a fine sequential hand motor skill, comparable to playing the piano or learning to type, improves not only due to physical practice, but also due to motor imagery. Previous studies revealed that transcranial direct current stimulation (tDCS) and motor imagery independently affect motor

Technology-aided assessment of sensori-motor function in early infancy

Directory of Open Access Journals (Sweden)

Alessandro G Allievi

2014-10-01

Full Text Available There is a pressing need for new techniques capable of providing accurate information about sensori-motor function during the first 2 years of childhood. Here we review current clinical methods and challenges for assessing motor function in early infancy, and discuss the potential benefits of applying technology-assisted methods. We also describe how the use of these tools with neuroimaging, and in particular functional magnetic resonance imaging (fMRI, can shed new light on the intra-cerebral processes underlying neurodevelopmental impairment. This knowledge is of particular relevance in the early infant brain which has an increased capacity for compensatory neural plasticity. Such tools could bring a wealth of knowledge about the underlying pathophysiological processes of diseases such as cerebral palsy; act as biomarkers to monitor the effects of possible therapeutic interventions; and provide clinicians with much needed early diagnostic information.

System and method for motor fault detection using stator current noise cancellation

Science.gov (United States)

Zhou, Wei; Lu, Bin; Nowak, Michael P.; Dimino, Steven A.

2010-12-07

A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to acquire at least on additional set of real-time operating current data from the motor during operation, redefine the noise component present in each additional set of real-time operating current data, and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

5-HT modulation of hyperpolarization-activated inward current and calcium- dependent outward current in a crustacean motor neuron

DEFF Research Database (Denmark)

Kiehn, O.; Harris-Warrick, R. M.

1992-01-01

1. Serotonergic modulation of a hyperpolarization-activated inward current, I(h), and a calcium-dependent outward current, I(o(Ca)), was examined in the dorsal gastric (DG) motor neuron, with the use of intracellular recording techniques in an isolated preparation of the crab stomatogastric....... The time course of activation of I(h) was well fitted by a single exponential function and strongly voltage dependent. 5-HT increased the rate of activation of I(h). 5- HT also slowed the rate of deactivation of the I(h) tail on repolarization to -50 mV. 6. The activation curve for the conductance (G...... reduced or eliminated the 5-HT response in the depolarizing range, suggesting that 5-HT specifically reduces I(o(Ca)). 11. These results demonstrate that 5-HT has dual effects on the DG motor neuron, in the crab stomatogastric ganglion. We suggest that changes in the two conductances are responsible...

Discrete-Time LPV Current Control of an Induction Motor

DEFF Research Database (Denmark)

Bendtsen, Jan Dimon; Trangbæk, Klaus

2001-01-01

In this paper we apply a new method for gain-scheduled output feedback control of nonlinear systems to current control of an induction motor. The method relies on recently developed controller synthesis results for linear parameter-varying (LPV) systems, where the controller synthesis is formulated...... without further complications. The synthesis method is applied to the model, yielding an LPV discrete-time controller. Finally, the efficiency of the control scheme is validated via simulations as well as experimentally on the actual induction motor, both in open-loop current control and when an outer...... speed control loop is closed around the current loop...

Discrete-Time LPV Current Control of an Induction Motor

DEFF Research Database (Denmark)

Bendtsen, Jan Dimon; Trangbæk, Klaus

2003-01-01

In this paper we apply a new method for gain-scheduled output feedback control of nonlinear systems to current control of an induction motor. The method relies on recently developed controller synthesis results for linear parameter-varying (LPV) systems, where the controller synthesis is formulated...... further complications. The synthesis method is applied to the model, yielding an LPV discrete-time controller. Finally, the efficiency of the control scheme is validated via simulations as well as on the actual induction motor, both in open-loop current control and when an outer speed control loop...... is closed around the current loop....

Motor skills training promotes motor functional recovery and induces synaptogenesis in the motor cortex and striatum after intracerebral hemorrhage in rats.

Science.gov (United States)

Tamakoshi, Keigo; Ishida, Akimasa; Takamatsu, Yasuyuki; Hamakawa, Michiru; Nakashima, Hiroki; Shimada, Haruka; Ishida, Kazuto

2014-03-01

We investigated the effects of motor skills training on several types of motor function and synaptic plasticity following intracerebral hemorrhage (ICH) in rats. Male Wistar rats were injected with collagenase into the left striatum to induce ICH, and they were randomly assigned to the ICH or sham groups. Each group was divided into the motor skills training (acrobatic training) and control (no exercise) groups. The acrobatic group performed acrobatic training from 4 to 28 days after surgery. Motor functions were assessed by motor deficit score, the horizontal ladder test and the wide or narrow beam walking test at several time points after ICH. The number of ΔFosB-positive cells was counted using immunohistochemistry to examine neuronal activation, and the PSD95 protein levels were analyzed by Western blotting to examine synaptic plasticity in the bilateral sensorimotor cortices and striata at 14 and 29 days after ICH. Motor skills training following ICH significantly improved gross motor function in the early phase after ICH and skilled motor coordinated function in the late phase. The number of ΔFosB-positive cells in the contralateral sensorimotor cortex in the acrobatic group significantly increased compared to the control group. PSD95 protein expression in the motor cortex significantly increased in the late phase, and in the striatum, the protein level significantly increased in the early phase by motor skills training after ICH compared to no training after ICH. We demonstrated that motor skills training improved motor function after ICH in rats and enhanced the neural activity and synaptic plasticity in the striatum and sensorimotor cortex. Copyright © 2013 Elsevier B.V. All rights reserved.

Exchange of rotor components in functioning bacterial flagellar motor

International Nuclear Information System (INIS)

Fukuoka, Hajime; Inoue, Yuichi; Terasawa, Shun; Takahashi, Hiroto; Ishijima, Akihiko

2010-01-01

The bacterial flagellar motor is a rotary motor driven by the electrochemical potential of a coupling ion. The interaction between a rotor and stator units is thought to generate torque. The overall structure of flagellar motor has been thought to be static, however, it was recently proved that stators are exchanged in a rotating motor. Understanding the dynamics of rotor components in functioning motor is important for the clarifying of working mechanism of bacterial flagellar motor. In this study, we focused on the dynamics and the turnover of rotor components in a functioning flagellar motor. Expression systems for GFP-FliN, FliM-GFP, and GFP-FliG were constructed, and each GFP-fusion was functionally incorporated into the flagellar motor. To investigate whether the rotor components are exchanged in a rotating motor, we performed fluorescence recovery after photobleaching experiments using total internal reflection fluorescence microscopy. After photobleaching, in a tethered cell producing GFP-FliN or FliM-GFP, the recovery of fluorescence at the rotational center was observed. However, in a cell producing GFP-FliG, no recovery of fluorescence was observed. The transition phase of fluorescence intensity after full or partially photobleaching allowed the turnover of FliN subunits to be calculated as 0.0007 s -1 , meaning that FliN would be exchanged in tens of minutes. These novel findings indicate that a bacterial flagellar motor is not a static structure even in functioning state. This is the first report for the exchange of rotor components in a functioning bacterial flagellar motor.

Task-relevant cognitive and motor functions are prioritized during prolonged speed-accuracy motor task performance.

Science.gov (United States)

Solianik, Rima; Satas, Andrius; Mickeviciene, Dalia; Cekanauskaite, Agne; Valanciene, Dovile; Majauskiene, Daiva; Skurvydas, Albertas

2018-06-01

This study aimed to explore the effect of prolonged speed-accuracy motor task on the indicators of psychological, cognitive, psychomotor and motor function. Ten young men aged 21.1 ± 1.0 years performed a fast- and accurate-reaching movement task and a control task. Both tasks were performed for 2 h. Despite decreased motivation, and increased perception of effort as well as subjective feeling of fatigue, speed-accuracy motor task performance improved during the whole period of task execution. After the motor task, the increased working memory function and prefrontal cortex oxygenation at rest and during conflict detection, and the decreased efficiency of incorrect response inhibition and visuomotor tracking were observed. The speed-accuracy motor task increased the amplitude of motor-evoked potentials, while grip strength was not affected. These findings demonstrate that to sustain the performance of 2-h speed-accuracy task under conditions of self-reported fatigue, task-relevant functions are maintained or even improved, whereas less critical functions are impaired.

Evaluating rodent motor functions: Which tests to choose?

Science.gov (United States)

Schönfeld, Lisa-Maria; Dooley, Dearbhaile; Jahanshahi, Ali; Temel, Yasin; Hendrix, Sven

2017-12-01

Damage to the motor cortex induced by stroke or traumatic brain injury (TBI) can result in chronic motor deficits. For the development and improvement of therapies, animal models which possess symptoms comparable to the clinical population are used. However, the use of experimental animals raises valid ethical and methodological concerns. To decrease discomfort by experimental procedures and to increase the quality of results, non-invasive and sensitive rodent motor tests are needed. A broad variety of rodent motor tests are available to determine deficits after stroke or TBI. The current review describes and evaluates motor tests that fall into three categories: Tests to evaluate fine motor skills and grip strength, tests for gait and inter-limb coordination and neurological deficit scores. In this review, we share our thoughts on standardized data presentation to increase data comparability between studies. We also critically evaluate current methods and provide recommendations for choosing the best behavioral test for a new research line. Copyright © 2017 Elsevier Ltd. All rights reserved.

Executive functioning, motor programming, and functional independence: accounting for variance, people, and time.

Science.gov (United States)

Kraybill, Matthew L; Suchy, Yana

2011-02-01

Assessing functional independence is an important part of making diagnostic decisions and treatment recommendations but is often complicated by the limitations of self-report and behavioral measures. Alternatively, it may be worthwhile to investigate neurocognitive correlates of incipient functional declines including using tests of executive functioning (EF) and motor programming (MP). The current study examined an electronic MP task and pitted it against other assessment instruments to evaluate its relative utility in assessing both EF and functional independence. Participants were 72 community-dwelling older adults. Results of this study showed that the MP task was correlated with other measures of EF, an efficient and reliable predictor of functionality, useful for identifying at-risk patients, and comparable to a longer battery in terms of sensitivity and specificity.

Retrospectively Assessed Early Motor and Current Pragmatic Language Skills in Autistic and Neurotypical Children.

Science.gov (United States)

Stevenson, Jennifer L; Lindley, Caitlin E; Murlo, Nicole

2017-08-01

Autistic individuals often struggle developmentally, even in areas that are not explicit diagnostic criteria, such as motor skills. This study explored the relation between early motor skills, assessed retrospectively, and current pragmatic language skills. Caregivers of neurotypical and autistic children, matched on gender and age, completed assessments of their child's early motor development and current language abilities. Early motor skills were correlated with later pragmatic language skills, and autistic children exhibited fewer motor skills than neurotypical children. In fact, motor skills were a better predictor of an autism spectrum diagnosis than were scores on a measure of current pragmatic language. These results highlight the important role of motor skills in autism spectrum disorders.

Functional connectivity between somatosensory and motor brain areas predicts individual differences in motor learning by observing.

Science.gov (United States)

McGregor, Heather R; Gribble, Paul L

2017-08-01

Action observation can facilitate the acquisition of novel motor skills; however, there is considerable individual variability in the extent to which observation promotes motor learning. Here we tested the hypothesis that individual differences in brain function or structure can predict subsequent observation-related gains in motor learning. Subjects underwent an anatomical MRI scan and resting-state fMRI scans to assess preobservation gray matter volume and preobservation resting-state functional connectivity (FC), respectively. On the following day, subjects observed a video of a tutor adapting her reaches to a novel force field. After observation, subjects performed reaches in a force field as a behavioral assessment of gains in motor learning resulting from observation. We found that individual differences in resting-state FC, but not gray matter volume, predicted postobservation gains in motor learning. Preobservation resting-state FC between left primary somatosensory cortex and bilateral dorsal premotor cortex, primary motor cortex, and primary somatosensory cortex and left superior parietal lobule was positively correlated with behavioral measures of postobservation motor learning. Sensory-motor resting-state FC can thus predict the extent to which observation will promote subsequent motor learning. NEW & NOTEWORTHY We show that individual differences in preobservation brain function can predict subsequent observation-related gains in motor learning. Preobservation resting-state functional connectivity within a sensory-motor network may be used as a biomarker for the extent to which observation promotes motor learning. This kind of information may be useful if observation is to be used as a way to boost neuroplasticity and sensory-motor recovery for patients undergoing rehabilitation for diseases that impair movement such as stroke. Copyright © 2017 the American Physiological Society.

Intrasurgical mapping of complex motor function in the superior frontal gyrus.

Science.gov (United States)

Martino, J; Gabarrós, A; Deus, J; Juncadella, M; Acebes, J J; Torres, A; Pujol, J

2011-04-14

A lesion to the superior frontal gyrus (SFG) has been associated with long-lasting deficits in complex motor functions. The aim of this study was to analyze the functional role of the SFG by means of electrical cortical stimulation. Direct intraoperative electrical stimulation was used in a group of 21 subjects with lesions within or close to the SFG while they performed three motor tasks that require high skills or bimanual synergy. The results were compared to functional magnetic resonance imaging (fMRI). Ninety-four of the 98 (94.9%) labels identified were located on the convexity surface of the SFG and only four (4.1%) labels were located on the middle surface of the SFG. Areas of blockage of the three tasks were identified in six of the 12 (50%) hemispheres with lesions that had infiltrated the SFG, compared to all 10 of the 10 hemispheres (100%) with lesions that spared the SFG. The difference between these two proportions was statistically significant (P=0.015). fMRI activation was mainly located on the medial aspect of the SFG. We show that the convexity surface of the SFG has an important role in bilateral control of complex movements and in bimanual coordination. The infiltration of the posterior part of the SFG by a lesion disturbs some of the complex hand motor functions, which may be assumed by the contralesional homologous area. Finally, the current study emphasizes the discrepancies between fMRI and intraoperative electrical stimulation maps in complex hand motor function. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Design of Controller for Reducing In-Rush Current of Single-Phase Induction Motor

Energy Technology Data Exchange (ETDEWEB)

Park, Su Kang; Baek, Hyung Lae; Lee, Sang Il [Chosun University, Kwangju (Korea)

2001-05-01

During an AC motor's start-up accelerating period, a large amount of current is required to reach to the rating speed. This is called in-rush current. This peak in-rush current can be more than about several times the operating or steady-state current in the full load rating of the motor. In-rush current is present in both and electronic ballasts. The main area of concern is the tripping of circuit breaker and fuses which can affect electrical system components From this, we can see that the electrical power controllers will be rather concerned, since they have to supply the actual current necessary to start the motor. This paper presents a new method to reducing in-rush current and energy saving of the single-phase induction motor used in air-conditioner. It can be obtained that proposed system is low cost and small size as compared with other controller. Experiments are focused on a capacitor starting single-phase induction motor. The optimal power saving and in-rush current limiting by phase angle control are verified by experimental results. Also, auxiliary winding was controlled by electronic starting switch. (author). 10 refs., 13 figs., 2 tabs.

Discrete-Time LPV Current Control of an Induction Motor

DEFF Research Database (Denmark)

Bendtsen, Jan Dimon; Trangbæk, Klaus

2003-01-01

In this paper we apply a new method for gain-scheduled output feedback control of nonlinear systems to current control of an induction motor. The method relies on recently developed controller synthesis results for linear parameter-varying (LPV) systems, where the controller synthesis is formulated...... as a set of linear matrix inequalities with full-block multipliers. A standard nonlinear model of the motor is constructed and written on LPV form. We then show that, although originally developed in continuous time, the controller synthesis results can be applied to a discrete-time model as well without...... further complications. The synthesis method is applied to the model, yielding an LPV discrete-time controller. Finally, the efficiency of the control scheme is validated via simulations as well as on the actual induction motor, both in open-loop current control and when an outer speed control loop...

Relationship between muscle strength and motor function in Duchenne muscular dystrophy

Directory of Open Access Journals (Sweden)

Milene F. Nunes

2016-07-01

Full Text Available ABSTRACT Measuring muscle strength and motor function is part of Duchenne muscular dystrophy (DMD assessment. However, the relationship between these variables is controversial. Objective To investigate the relationship between muscle strength and motor function and between these variables and age. Method Muscle strength was measured by Medical Research Council (MRC scale and motor function, by Motor Function Measure (MFM, in 40 non-ambulatory patients. Spearman tests investigated the relationships between muscle strength, motor function and age. Results Total MRC and MFM scores were strongly related to each other (r = 0.94; p 0.05. Strong and moderate relationships between partial muscle strength and motor function scores were found. Higher correlation coefficients were found between total scores and Dimensions 2 (axial/ proximal control and 3 (distal control of MFM. Conclusion Muscle strength and motor function are strongly correlated and seem to decrease proportionally in DMD.

Research on the induction motor current signature for centrifugal pump at cavitation condition

Directory of Open Access Journals (Sweden)

Yin Luo

2015-11-01

Full Text Available Cavitation is a major undesirable phenomenon for centrifugal pump because it can cause hydraulic performance deterioration, pump damage by pitting and material erosion, and structural vibration and noise. Cavitation can appear within the entire range of the operating conditions; therefore, it must be prevented by all means. Sensorless monitoring technology based on motor current signature analysis is non-intrusive and economic for monitoring motor-driven equipment. Thus, this technology is suitable for centrifugal pump systems. The motor current signature for centrifugal pump load at the cavitation condition is the basis of this technology. However, systematic research is lacking on sensorless monitoring technology based on motor current signature. As a result, the tentative exploration for motor current signature at cavitation load was conducted in this study. The results show that the stator current is still a sinusoidal alternating current strictly to the law of sine. Moreover, the root mean square of the current fluctuates because of different flow regimes in the cavitation progress and decreases because vapor density is smaller than water density when cavitation is fully formed. For the stator current spectrum, the noise level, noise distribution, rotation speed, and vane pass frequency components show features in the cavitation process. These indicator indexes change according to the stage of cavitation development. Thus, the motor current signature analysis is found to be a feasible and cost-effective method for the stages of cavitation condition.

Relation between hand function and gross motor function in full term infants aged 4 to 8 months

Science.gov (United States)

Nogueira, Solange F.; Figueiredo, Elyonara M.; Gonçalves, Rejane V.; Mancini, Marisa C.

2015-01-01

Background: In children, reaching emerges around four months of age, which is followed by rapid changes in hand function and concomitant changes in gross motor function, including the acquisition of independent sitting. Although there is a close functional relationship between these domains, to date they have been investigated separately. Objective: To investigate the longitudinal profile of changes and the relationship between the development of hand function (i.e. reaching for and manipulating an object) and gross motor function in 13 normally developing children born at term who were evaluated every 15 days from 4 to 8 months of age. Method: The number of reaches and the period (i.e. time) of manipulation to an object were extracted from video synchronized with the Qualisys(r) movement analysis system. Gross motor function was measured using the Alberta Infant Motor Scale. ANOVA for repeated measures was used to test the effect of age on the number of reaches, the time of manipulation and gross motor function. Hierarchical regression models were used to test the associations of reaching and manipulation with gross motor function. Results: Results revealed a significant increase in the number of reaches (pgross motor function (pgross motor function (R2=0.84; pgross motor function (R2=0.13; p=0.02) from 4 to 6 months of age. Associations from 6 to 8 months of age were not significant. Conclusion: The relationship between hand function and gross motor function was not constant, and the age span from 4 to 6 months was a critical period of interdependency of hand function and gross motor function development. PMID:25714437

Effects of mirror therapy through functional activites and motor standards in motor function of the upper limb after stroke

OpenAIRE

Medeiros, Candice Simões Pimenta de; Fernandes, Sabrina Gabrielle Gomes; Lopes, Johnnatas Mikael; Cacho, Enio Walker Azevedo; Cacho, Roberta de Oliveira

2014-01-01

The study aimed to evaluate the effects of mirror therapy through functional activities and motor standards in upper limb function of chronic stroke subjects. Six patients with paresis of the arm within at least six months after stroke were randomly to a group of functional activities (GAF - n=3) and group of motor standards (GPM - n=3). Both groups performed 15 sessions of mirror therapy for 30 minutes, but the first one (GAF) were instructed to do the bilateral and symmetrical movements bas...

Effect of Transcranial Direct Current Stimulation on Severely Affected Arm-Hand Motor Function in Patients After an Acute Ischemic Stroke: A Pilot Randomized Control Trial.

Science.gov (United States)

Rabadi, Meheroz H; Aston, Christopher E

2017-10-01

The aim of this article was to determine whether cathodal transcranial direct current stimulation (c-tDCS) to unaffected primary motor cortex (PMC) plus conventional occupational therapy (OT) improves functional motor recovery of the affected arm hand in patients after an acute ischemic stroke compared with sham transcranial direct current stimulation plus conventional OT. In this prospective, randomized, double-blinded, sham-controlled trial of 16 severe, acute ischemic stroke patients with severe arm-hand weakness were randomly assigned to either experimental (c-tDCS plus OT; n = 8) or control (sham transcranial direct current stimulation plus OT; n = 8) groups. All patients received a standard 3-hr in-patient rehabilitation therapy, plus an additional ten 30-min sessions of tDCS. During each session, 1 mA of cathodal stimulation to the unaffected PMC is performed followed by the patient's scheduled OT. The primary outcome measure was change in Action Research Arm Test (ARAT) total and subscores on discharge. Application of c-tDCS to unaffected PMC resulted in a clinically relevant 10-point improvement in the affected arm-hand function based on ARAT total score compared with a 2-point improvement in the control group. Application of 30-min of c-tDCS to the unaffected PMC showed a 10-point improvement in the ARAT score. This corresponds to a large effect size in improvement of affected arm-hand function in patients with severe, acute ischemic stroke. Although not statistically significant, this suggests that larger studies, enrolling at least 25 patients in each group, and with a longer follow-up are warranted.

Non-invasive brain stimulation to promote motor and functional recovery following spinal cord injury

Directory of Open Access Journals (Sweden)

Aysegul Gunduz

2017-01-01

Full Text Available We conducted a systematic review of studies using non-invasive brain stimulation (NIBS: repetitive transcranial magnetic stimulation (rTMS and transcranial direct current stimulation (tDCS as a research and clinical tool aimed at improving motor and functional recovery or spasticity in patients following spinal cord injury (SCI under the assumption that if the residual corticospinal circuits could be stimulated appropriately, the changes might be accompanied by functional recovery or an improvement in spasticity. This review summarizes the literature on the changes induced by NIBS in the motor and functional recovery and spasticity control of the upper and lower extremities following SCI.

Maturation of Sensori-Motor Functional Responses in the Preterm Brain.

Science.gov (United States)

Allievi, Alessandro G; Arichi, Tomoki; Tusor, Nora; Kimpton, Jessica; Arulkumaran, Sophie; Counsell, Serena J; Edwards, A David; Burdet, Etienne

2016-01-01

Preterm birth engenders an increased risk of conditions like cerebral palsy and therefore this time may be crucial for the brain's developing sensori-motor system. However, little is known about how cortical sensori-motor function matures at this time, whether development is influenced by experience, and about its role in spontaneous motor behavior. We aimed to systematically characterize spatial and temporal maturation of sensori-motor functional brain activity across this period using functional MRI and a custom-made robotic stimulation device. We studied 57 infants aged from 30 + 2 to 43 + 2 weeks postmenstrual age. Following both induced and spontaneous right wrist movements, we saw consistent positive blood oxygen level-dependent functional responses in the contralateral (left) primary somatosensory and motor cortices. In addition, we saw a maturational trend toward faster, higher amplitude, and more spatially dispersed functional responses; and increasing integration of the ipsilateral hemisphere and sensori-motor associative areas. We also found that interhemispheric functional connectivity was significantly related to ex-utero exposure, suggesting the influence of experience-dependent mechanisms. At term equivalent age, we saw a decrease in both response amplitude and interhemispheric functional connectivity, and an increase in spatial specificity, culminating in the establishment of a sensori-motor functional response similar to that seen in adults. © The Author 2015. Published by Oxford University Press.

A novel method for assessing the development of speech motor function in toddlers with autism spectrum disorders

Directory of Open Access Journals (Sweden)

Katherine eSullivan

2013-03-01

Full Text Available There is increasing evidence to show that indicators other than socio-cognitive abilities might predict communicative function in Autism Spectrum Disorders (ASD. A potential area of research is the development of speech motor function in toddlers. Utilizing a novel measure called ‘articulatory features’, we assess the abilities of toddlers to produce sounds at different timescales as a metric of their speech motor skills. In the current study, we examined 1 whether speech motor function differed between toddlers with ASD, developmental delay, and typical development; and 2 whether differences in speech motor function are correlated with standard measures of language in toddlers with ASD. Our results revealed significant differences between a subgroup of the ASD population with poor verbal skills, and the other groups for the articulatory features associated with the shortest time scale, namely place of articulation, (p<0.05. We also found significant correlations between articulatory features and language and motor ability as assessed by the Mullen and the Vineland scales for the ASD group. Our findings suggest that articulatory features may be an additional measure of speech motor function that could potentially be useful as an early risk indicator of ASD.

Relation between hand function and gross motor function in full term infants aged 4 to 8 months

Directory of Open Access Journals (Sweden)

Solange F. Nogueira

2015-02-01

Full Text Available Background: In children, reaching emerges around four months of age, which is followed by rapid changes in hand function and concomitant changes in gross motor function, including the acquisition of independent sitting. Although there is a close functional relationship between these domains, to date they have been investigated separately. Objective: To investigate the longitudinal profile of changes and the relationship between the development of hand function (i.e. reaching for and manipulating an object and gross motor function in 13 normally developing children born at term who were evaluated every 15 days from 4 to 8 months of age. Method: The number of reaches and the period (i.e. time of manipulation to an object were extracted from video synchronized with the Qualisys(r movement analysis system. Gross motor function was measured using the Alberta Infant Motor Scale. ANOVA for repeated measures was used to test the effect of age on the number of reaches, the time of manipulation and gross motor function. Hierarchical regression models were used to test the associations of reaching and manipulation with gross motor function. Results: Results revealed a significant increase in the number of reaches (p<0.001, the time of manipulation (p<0.001 and gross motor function (p<0.001 over time, as well as associations between reaching and gross motor function (R2=0.84; p<0.001 and manipulation and gross motor function (R2=0.13; p=0.02 from 4 to 6 months of age. Associations from 6 to 8 months of age were not significant. Conclusion: The relationship between hand function and gross motor function was not constant, and the age span from 4 to 6 months was a critical period of interdependency of hand function and gross motor function development.

Combined motor cortex and spinal cord neuromodulation promotes corticospinal system functional and structural plasticity and motor function after injury.

Science.gov (United States)

Song, Weiguo; Amer, Alzahraa; Ryan, Daniel; Martin, John H

2016-03-01

An important strategy for promoting voluntary movements after motor system injury is to harness activity-dependent corticospinal tract (CST) plasticity. We combine forelimb motor cortex (M1) activation with co-activation of its cervical spinal targets in rats to promote CST sprouting and skilled limb movement after pyramidal tract lesion (PTX). We used a two-step experimental design in which we first established the optimal combined stimulation protocol in intact rats and then used the optimal protocol in injured animals to promote CST repair and motor recovery. M1 was activated epidurally using an electrical analog of intermittent theta burst stimulation (iTBS). The cervical spinal cord was co-activated by trans-spinal direct current stimulation (tsDCS) that was targeted to the cervical enlargement, simulated from finite element method. In intact rats, forelimb motor evoked potentials (MEPs) were strongly facilitated during iTBS and for 10 min after cessation of stimulation. Cathodal, not anodal, tsDCS alone facilitated MEPs and also produced a facilitatory aftereffect that peaked at 10 min. Combined iTBS and cathodal tsDCS (c-tsDCS) produced further MEP enhancement during stimulation, but without further aftereffect enhancement. Correlations between forelimb M1 local field potentials and forelimb electromyogram (EMG) during locomotion increased after electrical iTBS alone and further increased with combined stimulation (iTBS+c-tsDCS). This optimized combined stimulation was then used to promote function after PTX because it enhanced functional connections between M1 and spinal circuits and greater M1 engagement in muscle contraction than either stimulation alone. Daily application of combined M1 iTBS on the intact side and c-tsDCS after PTX (10 days, 27 min/day) significantly restored skilled movements during horizontal ladder walking. Stimulation produced a 5.4-fold increase in spared ipsilateral CST terminations. Combined neuromodulation achieves optimal motor

Cytoskeleton Molecular Motors: Structures and Their Functions in Neuron.

Science.gov (United States)

Xiao, Qingpin; Hu, Xiaohui; Wei, Zhiyi; Tam, Kin Yip

2016-01-01

Cells make use of molecular motors to transport small molecules, macromolecules and cellular organelles to target region to execute biological functions, which is utmost important for polarized cells, such as neurons. In particular, cytoskeleton motors play fundamental roles in neuron polarization, extension, shape and neurotransmission. Cytoskeleton motors comprise of myosin, kinesin and cytoplasmic dynein. F-actin filaments act as myosin track, while kinesin and cytoplasmic dynein move on microtubules. Cytoskeleton motors work together to build a highly polarized and regulated system in neuronal cells via different molecular mechanisms and functional regulations. This review discusses the structures and working mechanisms of the cytoskeleton motors in neurons.

Abnormal functional motor lateralization in healthy siblings of patients with schizophrenia.

Science.gov (United States)

Altamura, Mario; Fazio, Leonardo; De Salvia, Michela; Petito, Annamaria; Blasi, Giuseppe; Taurisano, Paolo; Romano, Raffaella; Gelao, Barbara; Bellomo, Antonello; Bertolino, Alessandro

2012-07-30

Earlier neuroimaging studies of motor function in schizophrenia have demonstrated reduced functional lateralization in the motor network during motor tasks. Here, we used event-related functional magnetic resonance imaging during a visually guided motor task in 18 clinically unaffected siblings of patients with schizophrenia and 24 matched controls to investigate if abnormal functional lateralization is related to genetic risk for this brain disorder. Whereas activity associated with motor task performance was mainly contralateral with only a marginal ipsilateral component in healthy participants, unaffected siblings had strong bilateral activity with significantly greater response in ipsilateral and contralateral premotor areas as well as in contralateral subcortical motor regions relative to controls. Reduced lateralization in siblings was also identified with a measure of laterality quotient. These findings suggest that abnormal functional lateralization of motor circuitry is related to genetic risk of schizophrenia. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Increasing Mud Pump Motor Reliability against Malfunctions of DC Motor Excitation System

Science.gov (United States)

Nikulin, O. V.; Shabanov, V. A.

2017-10-01

The most widely used drilling machinery, such as mud pumps, draw-works, and rotors, use direct-current (DC) motors with independent excitation as the electric drive. Drilling machinery drives operate in harsh ambient conditions, including those with the presence of moisture, dust and vibration, which increases the malfunction rate of both drilling equipment and their electric drives. One of the frequently encountered malfunctions are DC motor excitation coil faults, which disrupt the normal functioning of electric drives, often leading to shutdown of the drilling process. In a four-pole DC motor, the malfunction of one coil leads to lack of excitation current in just one coil pair, while the other pair remains functional. In this case, DC motors and drilling equipment can remain operational, which would allow for continuing the drilling process. This paper considers the possibility of operation of a DC motor on a drilling rig in those cases when one pair of excitation coils is non-functional, and describes the device for switching between the excitation coils and the auxiliary winding in a DC motor with independent excitation.

Functions of myosin motors tailored for parasitism

DEFF Research Database (Denmark)

Mueller, Christina; Graindorge, Arnault; Soldati-Favre, Dominique

2017-01-01

Myosin motors are one of the largest protein families in eukaryotes that exhibit divergent cellular functions. Their roles in protozoans, a diverse group of anciently diverged, single celled organisms with many prominent members known to be parasitic and to cause diseases in human and livestock......, are largely unknown. In the recent years many different approaches, among them whole genome sequencing, phylogenetic analyses and functional studies have increased our understanding on the distribution, protein architecture and function of unconventional myosin motors in protozoan parasites. In Apicomplexa......, myosins turn out to be highly specialized and to exhibit unique functions tailored to accommodate the lifestyle of these parasites....

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.

Evaluation of esophageal motor function in clinical practice.

Science.gov (United States)

Gyawali, C P; Bredenoord, A J; Conklin, J L; Fox, M; Pandolfino, J E; Peters, J H; Roman, S; Staiano, A; Vaezi, M F

2013-02-01

Esophageal motor function is highly coordinated between central and enteric nervous systems and the esophageal musculature, which consists of proximal skeletal and distal smooth muscle in three functional regions, the upper and lower esophageal sphincters, and the esophageal body. While upper endoscopy is useful in evaluating for structural disorders of the esophagus, barium esophagography, radionuclide transit studies, and esophageal intraluminal impedance evaluate esophageal transit and partially assess motor function. However, esophageal manometry is the test of choice for the evaluation of esophageal motor function. In recent years, high-resolution manometry (HRM) has streamlined the process of acquisition and display of esophageal pressure data, while uncovering hitherto unrecognized esophageal physiologic mechanisms and pathophysiologic patterns. New algorithms have been devised for analysis and reporting of esophageal pressure topography from HRM. The clinical value of HRM extends to the pediatric population, and complements preoperative evaluation prior to foregut surgery. Provocative maneuvers during HRM may add to the assessment of esophageal motor function. The addition of impedance to HRM provides bolus transit data, but impact on clinical management remains unclear. Emerging techniques such as 3-D HRM and impedance planimetry show promise in the assessment of esophageal sphincter function and esophageal biomechanics. © 2013 Blackwell Publishing Ltd.

Cognitive and cognitive-motor interventions affecting physical functioning: A systematic review

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Murer Kurt

2011-06-01

Full Text Available Abstract Background Several types of cognitive or combined cognitive-motor intervention types that might influence physical functions have been proposed in the past: training of dual-tasking abilities, and improving cognitive function through behavioral interventions or the use of computer games. The objective of this systematic review was to examine the literature regarding the use of cognitive and cognitive-motor interventions to improve physical functioning in older adults or people with neurological impairments that are similar to cognitive impairments seen in aging. The aim was to identify potentially promising methods that might be used in future intervention type studies for older adults. Methods A systematic search was conducted for the Medline/Premedline, PsycINFO, CINAHL and EMBASE databases. The search was focused on older adults over the age of 65. To increase the number of articles for review, we also included those discussing adult patients with neurological impairments due to trauma, as these cognitive impairments are similar to those seen in the aging population. The search was restricted to English, German and French language literature without any limitation of publication date or restriction by study design. Cognitive or cognitive-motor interventions were defined as dual-tasking, virtual reality exercise, cognitive exercise, or a combination of these. Results 28 articles met our inclusion criteria. Three articles used an isolated cognitive rehabilitation intervention, seven articles used a dual-task intervention and 19 applied a computerized intervention. There is evidence to suggest that cognitive or motor-cognitive methods positively affects physical functioning, such as postural control, walking abilities and general functions of the upper and lower extremities, respectively. The majority of the included studies resulted in improvements of the assessed functional outcome measures. Conclusions The current evidence on the

Language and motor function thresholds during pediatric extra-operative electrical cortical stimulation brain mapping.

Science.gov (United States)

Zea Vera, Alonso; Aungaroon, Gewalin; Horn, Paul S; Byars, Anna W; Greiner, Hansel M; Tenney, Jeffrey R; Arthur, Todd M; Crone, Nathan E; Holland, Katherine D; Mangano, Francesco T; Arya, Ravindra

2017-10-01

To examine current thresholds and their determinants for language and motor mapping with extra-operative electrical cortical stimulation (ECS). ECS electrocorticograph recordings were reviewed to determine functional thresholds. Predictors of functional thresholds were found with multivariable analyses. In 122 patients (age 11.9±5.4years), average minimum, frontal, and temporal language thresholds were 7.4 (± 3.0), 7.8 (± 3.0), and 7.4 (± 3.1) mA respectively. Average minimum, face, upper and lower extremity motor thresholds were 5.4 (± 2.8), 6.1 (± 2.8), 4.9 (± 2.3), and 5.3 (± 3.3) mA respectively. Functional and after-discharge (AD)/seizure thresholds were significantly related. Minimum, frontal, and temporal language thresholds were higher than AD thresholds at all ages. Minimum motor threshold was higher than minimum AD threshold up to 8.0years of age, face motor threshold was higher than frontal AD threshold up to 11.8years age, and lower subsequently. UE motor thresholds remained below frontal AD thresholds throughout the age range. Functional thresholds are frequently above AD thresholds in younger children. These findings raise concerns about safety and neurophysiologic validity of ECS mapping. Functional and AD/seizure thresholds relationships suggest individual differences in cortical excitability which cannot be explained by clinical variables. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Perceptual-motor functioning in children with phenylketonuria.

Science.gov (United States)

Koff, E; Boyle, P; Pueschel, S M

1977-10-01

Children with treated phenylketonuria (PKU) have been described as being at high risk for perceptual-motor dysfunction. In this study, the Wechsler Intelligence Scale for Children (WISC) and the Bender Gestalt test were administered to 19 school age children with treated PKU and of average intelligence who have been off diet from five months to six years four months. Perceptual-motor performance was evaluated, and school functioning was rated by classroom teachers. Substantial impairment of perceptual-motor functioning as measured by the Bender Gestalt test and lower WISC performance IQs than verbal IQs were observed in children of average intelligence. Quality of dietary control was found to be associated with performance on the Bender Gestalt test. These findings suggest the possibility of a specific deficit that could seriously interfere with academic progress, but which is not signalled by obvious impairment of overall intellectual functioning.

Start Up Current Control of Buck-Boost Convertor-Fed Serial DC Motor

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Yusuf SÖNMEZ

2009-02-01

Full Text Available Generally, DC motors are given preference for industrial applications such as electric locomotives, cranes, goods lifts. Because of they have high starting moment; they initially start with high current. This high start-up current must be decreased since it may damage windings of the motor and increases power consumption. It could be controlled by an appropriate driver system and controller. The nature of fuzzy logic control has adaptive characteristics that can achieve robust response to a system with uncertainty, parameter variation, and load disturbance. In this paper, fuzzy logic based control of start-up current of a Buck-Boost Converter fed serial DC motor is examined through computer simulation. In order to see the advantages of fuzzy logic control, classical PI control has applied to the same motor, under same circumstances and has been compared. C++ Builder software has been used for the simulation. According to the simulation results, plainly, fuzzy logic control has stronger responses than classical PI control and uses lower current at starting moment.

Functional imaging in pre-motor Parkinson’s disease

International Nuclear Information System (INIS)

Arnaldi, D.; Picco, A.; Ferrara, M.; Nobili, F.; Famà, F.; Buschiazzo, A.; Morbelli, S.; De Carli, F.

2014-01-01

Several non motor symptoms (NMS) can precede the onset of the classical motor Parkinson’s disease (PD) syndrome. The existence of pre-motor and even pre-clinical PD stages has been proposed but the best target population to be screened to disclose PD patients in a pre-clinical, thus asymptomatic, stage is still matter of debate. The REM sleep behavior disorder (RBD) often affects PD patients at different stages of the disease and could precede the onset of motor symptoms by several years. However, RBD could also precede other synucleinopathies (namely, dementia with Lewy bodies and multisystem atrophy), and less frequently could be related to other neurological conditions or remain idiopathic. Moreover, not all PD patients exhibit RBD. Despite these caveats, RBD probably represents the best feature to disclose pre-motor PD patients given its high-risk of developing a full motor syndrome. Other clinical clues in the premotor stages of PD undergoing active investigation include hyposmia, depression, and autonomic dysfunction. Effective biomarkers are needed in order to improve the diagnostic accuracy in the pre-motor stage of PD, to monitor disease progression and to plan both pharmacological and non-pharmacological intervention. Functional imaging, in particular radionuclide methodologies, has been often used to investigate dopaminergic and non-dopaminergic features as well as cortical functioning in patients with RBD in its idiopathic form (iRBD) and/or associated with PD. Recently, new tracers to image α-synuclein pathologies are under development. Functional imaging in pre-motor PD, and in particular in iRBD, could improve our knowledge about the underlying mechanisms and the neurodegenerative progress of PD

Discrete Current Control Strategy of Permanent Magnet Synchronous Motors

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Yan Dong

2013-01-01

Full Text Available A control strategy of permanent magnet synchronous motors (PMSMs, which is different from the traditional vector control (VC and direct torque control (DTC, is proposed. Firstly, the circular rotating magnetic field is analyzed on the simplified model and discredited into stepping magnetic field. The stepping magnetomotive force will drive the rotor to run as the stepping motor. Secondly, the stator current orientation is used to build the control model instead of rotor flux orientation. Then, the discrete current control strategy is set and adopted in positioning control. Three methods of the strategy are simulated in computer and tested on the experiment platform of PMSM. The control precision is also verified through the experiment.

Development of Rotor Diagnosis Method via Motor Current Signature Analysis

Energy Technology Data Exchange (ETDEWEB)

Park, Jin Seok; Huh, Hyung; Kim, Min Hwan; Jeong, Kyeong Hoon; Lee, Gyu Mhan; Park, Jin Ho; Park, Keun Bae; Lee, Cheol Kwon; Hur, S

2006-01-15

A study on motor current signature analysis has been performed to monitor a journal bearing fault due to increasing clearance. It was known that the journal bearing clearance produces side band frequencies, the supplied current frequency plus and minus rotational rotor frequency in motor current. But the existence information of the side band frequencies is not sufficient to diagnose whether the journal bearing is safe or not. Four journal bearing sets with different clearances are used to measure the side band frequency amplitude and the rotor vibration amplitude versus the journal bearing clearance. The side band frequency amplitude and the rotor vibration amplitude are increased as the journal bearing clearance is increasing. This trend assures that ASME OM vibration guide line can be applied to estimate the journal bearing clearance size. In this research, 2.5 times the reference side band amplitude is suggested as an indicator of a journal bearing fault. Further study is necessary to make out more specific quantitative relations between the side band frequency amplitude and the journal bearing clearance of a motor.

Development of Rotor Diagnosis Method via Motor Current Signature Analysis

International Nuclear Information System (INIS)

Park, Jin Seok; Huh, Hyung; Kim, Min Hwan; Jeong, Kyeong Hoon; Lee, Gyu Mhan; Park, Jin Ho; Park, Keun Bae; Lee, Cheol Kwon; Hur, S.

2006-01-01

A study on motor current signature analysis has been performed to monitor a journal bearing fault due to increasing clearance. It was known that the journal bearing clearance produces side band frequencies, the supplied current frequency plus and minus rotational rotor frequency in motor current. But the existence information of the side band frequencies is not sufficient to diagnose whether the journal bearing is safe or not. Four journal bearing sets with different clearances are used to measure the side band frequency amplitude and the rotor vibration amplitude versus the journal bearing clearance. The side band frequency amplitude and the rotor vibration amplitude are increased as the journal bearing clearance is increasing. This trend assures that ASME OM vibration guide line can be applied to estimate the journal bearing clearance size. In this research, 2.5 times the reference side band amplitude is suggested as an indicator of a journal bearing fault. Further study is necessary to make out more specific quantitative relations between the side band frequency amplitude and the journal bearing clearance of a motor

ATF3 expression improves motor function in the ALS mouse model by promoting motor neuron survival and retaining muscle innervation.

Science.gov (United States)

Seijffers, Rhona; Zhang, Jiangwen; Matthews, Jonathan C; Chen, Adam; Tamrazian, Eric; Babaniyi, Olusegun; Selig, Martin; Hynynen, Meri; Woolf, Clifford J; Brown, Robert H

2014-01-28

ALS is a fatal neurodegenerative disease characterized by a progressive loss of motor neurons and atrophy of distal axon terminals in muscle, resulting in loss of motor function. Motor end plates denervated by axonal retraction of dying motor neurons are partially reinnervated by remaining viable motor neurons; however, this axonal sprouting is insufficient to compensate for motor neuron loss. Activating transcription factor 3 (ATF3) promotes neuronal survival and axonal growth. Here, we reveal that forced expression of ATF3 in motor neurons of transgenic SOD1(G93A) ALS mice delays neuromuscular junction denervation by inducing axonal sprouting and enhancing motor neuron viability. Maintenance of neuromuscular junction innervation during the course of the disease in ATF3/SOD1(G93A) mice is associated with a substantial delay in muscle atrophy and improved motor performance. Although disease onset and mortality are delayed, disease duration is not affected. This study shows that adaptive axonal growth-promoting mechanisms can substantially improve motor function in ALS and importantly, that augmenting viability of the motor neuron soma and maintaining functional neuromuscular junction connections are both essential elements in therapy for motor neuron disease in the SOD1(G93A) mice. Accordingly, effective protection of optimal motor neuron function requires restitution of multiple dysregulated cellular pathways.

How Can a Ketogenic Diet Improve Motor Function?

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Charlotte Veyrat-Durebex

2018-01-01

Full Text Available A ketogenic diet (KD is a normocaloric diet composed by high fat (80–90%, low carbohydrate, and low protein consumption that induces fasting-like effects. KD increases ketone body (KBs production and its concentration in the blood, providing the brain an alternative energy supply that enhances oxidative mitochondrial metabolism. In addition to its profound impact on neuro-metabolism and bioenergetics, the neuroprotective effect of specific polyunsaturated fatty acids and KBs involves pleiotropic mechanisms, such as the modulation of neuronal membrane excitability, inflammation, or reactive oxygen species production. KD is a therapy that has been used for almost a century to treat medically intractable epilepsy and has been increasingly explored in a number of neurological diseases. Motor function has also been shown to be improved by KD and/or medium-chain triglyceride diets in rodent models of Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and spinal cord injury. These studies have proposed that KD may induce a modification in synaptic morphology and function, involving ionic channels, glutamatergic transmission, or synaptic vesicular cycling machinery. However, little is understood about the molecular mechanisms underlying the impact of KD on motor function and the perspectives of its use to acquire the neuromuscular effects. The aim of this review is to explore the conditions through which KD might improve motor function. First, we will describe the main consequences of KD exposure in tissues involved in motor function. Second, we will report and discuss the relevance of KD in pre-clinical and clinical trials in the major diseases presenting motor dysfunction.

Impact of cercal air currents on singing motor pattern generation in the cricket (Gryllus bimaculatus DeGeer)

Science.gov (United States)

2015-01-01

The cercal system of crickets detects low-frequency air currents produced by approaching predators and self-generated air currents during singing, which may provide sensory feedback to the singing motor network. We analyzed the effect of cercal stimulation on singing motor pattern generation to reveal the response of a singing interneuron to predator-like signals and to elucidate the possible role of self-generated air currents during singing. In fictive singing males, we recorded an interneuron of the singing network while applying air currents to the cerci; additionally, we analyzed the effect of abolishing the cercal system in freely singing males. In fictively singing crickets, the effect of short air stimuli is either to terminate prematurely or to lengthen the interchirp interval, depending on their phase in the chirp cycle. Within our stimulation paradigm, air stimuli of different velocities and durations always elicited an inhibitory postsynaptic potential in the singing interneuron. Current injection in the singing interneuron elicited singing motor activity, even during the air current-evoked inhibitory input from the cercal pathway. The disruptive effects of air stimuli on the fictive singing pattern and the inhibitory response of the singing interneuron point toward the cercal system being involved in initiating avoidance responses in singing crickets, according to the established role of cerci in a predator escape pathway. After abolishing the activity of the cercal system, the timing of natural singing activity was not significantly altered. Our study provides no evidence that self-generated cercal sensory activity has a feedback function for singing motor pattern generation. PMID:26334014

Ocular Motor Function in Patients with Bilateral Vestibular Weakness

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Seyyed Amir Hossein Ghazizadeh Hashemi

2016-05-01

Full Text Available Introduction: Patients with bilateral weakness (BW have many difficulties in gaze stability that interfere with their normal function. The aim of this study was to evaluate ocular motor functions in patients with BW to better understand the problem of gaze instability in these patients.   Materials and Methods: Patients were referred from the Otolaryngology Department for Vestibular Assessment to our clinic between November 2014 and March 2015. We assessed ocular motor function (gaze, saccade, and smooth pursuit in patients over the age of 18 years with BW, as verified by a caloric test.   Results: Seventy-eight patients completed all the tests. The mean age of patients was 51.9 (±15.9 years, and 47 (60% were female. Abnormal results were found in five (6.4%, 32 (41%, and seven (9% patients with respect to gaze, smooth pursuit, and saccade, respectively. There were positive but relatively weak relationships between age and ocular motor results.   Conclusion:  Patients with BW suffer from dizziness and unsteadiness. These patients have abnormal function in ocular motor (especially smooth pursuit tests. The ocular motor dysfunction is responsible for gaze instability in static positions such as standing.

Enhanced motor learning following task-concurrent dual transcranial direct current stimulation.

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Sophia Karok

Full Text Available OBJECTIVE: Transcranial direct current stimulation (tDCS of the primary motor cortex (M1 has beneficial effects on motor performance and motor learning in healthy subjects and is emerging as a promising tool for motor neurorehabilitation. Applying tDCS concurrently with a motor task has recently been found to be more effective than applying stimulation before the motor task. This study extends this finding to examine whether such task-concurrent stimulation further enhances motor learning on a dual M1 montage. METHOD: Twenty healthy, right-handed subjects received anodal tDCS to the right M1, dual tDCS (anodal current over right M1 and cathodal over left M1 and sham tDCS in a repeated-measures design. Stimulation was applied for 10 mins at 1.5 mA during an explicit motor learning task. Response times (RT and accuracy were measured at baseline, during, directly after and 15 mins after stimulation. Motor cortical excitability was recorded from both hemispheres before and after stimulation using single-pulse transcranial magnetic stimulation. RESULTS: Task-concurrent stimulation with a dual M1 montage significantly reduced RTs by 23% as early as with the onset of stimulation (p<0.01 with this effect increasing to 30% at the final measurement. Polarity-specific changes in cortical excitability were observed with MEPs significantly reduced by 12% in the left M1 and increased by 69% in the right M1. CONCLUSION: Performance improvement occurred earliest in the dual M1 condition with a stable and lasting effect. Unilateral anodal stimulation resulted only in trendwise improvement when compared to sham. Therefore, task-concurrent dual M1 stimulation is most suited for obtaining the desired neuromodulatory effects of tDCS in explicit motor learning.

Motor skills and functional characteristics of students of different somatotypes

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M.M. Kolokoltsev

2018-02-01

Full Text Available He purpose of the article is to study correlation of motor and functional characteristics of students of different somatotypes. Material : it was examined first year students (n=577, 17-18 years old. All students were trained in discipline “Physical education”. It was carried out somatotyping. It was considered motor skills and functional characteristics of students. Results : it was determined the reliable differences in values of parameters of motor tests and functional characteristics of students’ organism. It is determined that by the end of the first year of study the positive dynamics is registered: in sthenics (in two of seven motor tests; in asthenics (in four tests. It wasn’t found the reliable positive changes in group of hypersthenics. Students of sthenic and asthenic somatotypes have higher functional reserves of cardiorespiratory system, than girls of hypersthenics somatotype. Conclusions: constitutional features of motor skills and functional parameters of students of different somatotypes allow to concretize provisions of methodology of planning the individual differentiated training in discipline Physical education.

Comparison of Output Current Ripple in Single and Dual Three-Phase Inverters for Electric Vehicle Motor Drives

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Jelena Loncarski

2015-04-01

Full Text Available The standard solution for the traction system in battery powered electric vehicles (EVs is a two-level (2L inverter feeding a three-phase motor. A simple and effective way to achieve a three-level (3L inverter in battery-supplied electric vehicles consists of using two standard three-phase 2L inverters with the open-end winding connection of standard three-phase ac motors. The 3L inverter solution can be usefully adopted in EVs since it combines several benefits such as current ripple reduction, increment of phase motor voltage with limited voltage ratings of the two battery banks, improvement in system reliability, etc. The reduction in current ripple amplitude is particularly relevant since it is a source of electromagnetic interference and audio noise from the inverter-motor power connection cables and from the motor itself. By increasing the inverter switching frequency the ripple amplitude is reduced, but the drive efficiency decreases due to the proportionally increased switching losses. In this paper the peak-to-peak ripple amplitude of the dual-2L inverter is evaluated and compared with the corresponding ripple of the single-2L inverter, considering the same voltage and power motor ratings. The ripple analysis is carried out as a function of the modulation index to cover the whole modulation range of the inverter, and the theoretical results are verified with experimental tests carried out by an inverter-motor drive prototype.

Motor function and incident dementia: a systematic review and meta-analysis.

Science.gov (United States)

Kueper, Jacqueline Kathleen; Speechley, Mark; Lingum, Navena Rebecca; Montero-Odasso, Manuel

2017-09-01

cognitive and mobility decline are interrelated processes, whereby mobility decline coincides or precedes the onset of cognitive decline. to assess whether there is an association between performance on motor function tests and incident dementia. electronic database, grey literature and hand searching identified studies testing for associations between baseline motor function and incident dementia in older adults. of 2,540 potentially relevant documents, 37 met the final inclusion criteria and were reviewed qualitatively. Three meta-analyses were conducted using data from 10 studies. Three main motor domains-upper limb motor function, parkinsonism and lower limb motor function-emerged as associated with increased risk of incident dementia. Studies including older adults without neurological overt disease found a higher risk of incident dementia associated with poorer performance on composite motor function scores, balance and gait velocity (meta-analysis pooled HR = 1.94, 95% CI: 1.41, 2.65). Mixed results were found across different study samples for upper limb motor function, overall parkinsonism (meta-analysis pooled OR = 3.05, 95% CI: 1.31, 7.08), bradykinesia and rigidity. Studies restricted to older adults with Parkinson's Disease found weak or no association with incident dementia even for motor domains highly associated in less restrictive samples. Tremor was not associated with an increased risk of dementia in any population (meta-analysis pooled HR = 0.80, 95% CI 0.31, 2.03). lower limb motor function was associated with increased risk of developing dementia, while tremor and hand grip strength were not. Our results support future research investigating the inclusion of quantitative motor assessment, specifically gait velocity tests, for clinical dementia risk evaluation. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com

Catenin-dependent cadherin function drives divisional segregation of spinal motor neurons.

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Bello, Sanusi M; Millo, Hadas; Rajebhosale, Manisha; Price, Stephen R

2012-01-11

Motor neurons that control limb movements are organized as a neuronal nucleus in the developing ventral horn of the spinal cord called the lateral motor column. Neuronal migration segregates motor neurons into distinct lateral and medial divisions within the lateral motor column that project axons to dorsal or ventral limb targets, respectively. This migratory phase is followed by an aggregation phase whereby motor neurons within a division that project to the same muscle cluster together. These later phases of motor neuron organization depend on limb-regulated differential cadherin expression within motor neurons. Initially, all motor neurons display the same cadherin expression profile, which coincides with the migratory phase of motor neuron segregation. Here, we show that this early, pan-motor neuron cadherin function drives the divisional segregation of spinal motor neurons in the chicken embryo by controlling motor neuron migration. We manipulated pan-motor neuron cadherin function through dissociation of cadherin binding to their intracellular partners. We found that of the major intracellular transducers of cadherin signaling, γ-catenin and α-catenin predominate in the lateral motor column. In vivo manipulations that uncouple cadherin-catenin binding disrupt divisional segregation via deficits in motor neuron migration. Additionally, reduction of the expression of cadherin-7, a cadherin predominantly expressed in motor neurons only during their migration, also perturbs divisional segregation. Our results show that γ-catenin-dependent cadherin function is required for spinal motor neuron migration and divisional segregation and suggest a prolonged role for cadherin expression in all phases of motor neuron organization.

Motor cortex stimulation does not lead to functional recovery after experimental cortical injury in rats.

Science.gov (United States)

Schönfeld, Lisa-Maria; Jahanshahi, Ali; Lemmens, Evi; Bauwens, Matthias; Hescham, Sarah-Anna; Schipper, Sandra; Lagiere, Melanie; Hendrix, Sven; Temel, Yasin

2017-01-01

Motor impairments are among the major complications that develop after cortical damage caused by either stroke or traumatic brain injury. Motor cortex stimulation (MCS) can improve motor functions in animal models of stroke by inducing neuroplasticity. In the current study, the therapeutic effect of chronic MCS was assessed in a rat model of severe cortical damage. A controlled cortical impact (CCI) was applied to the forelimb area of the motor cortex followed by implantation of a flat electrode covering the lesioned area. Forelimb function was assessed using the Montoya staircase test and the cylinder test before and after a period of chronic MCS. Furthermore, the effect of MCS on tissue metabolism and lesion size was measured using [18F]-fluorodesoxyglucose (FDG) μPET scanning. CCI caused a considerable lesion at the level of the motor cortex and dorsal striatum together with a long-lasting behavioral phenotype of forelimb impairment. However, MCS applied to the CCI lesion did not lead to any improvement in limb functioning when compared to non-stimulated control rats. Also, MCS neither changed lesion size nor distribution of FDG. The use of MCS as a standalone treatment did not improve motor impairments in a rat model of severe cortical damage using our specific treatment modalities.

Functional MRI of motor speech area combined with motor stimulation during resting period

International Nuclear Information System (INIS)

Lim, Yeong Su; Park, Hark Hoon; Chung, Gyung Ho; Lee, Sang Yong; Chon, Su Bin; Kang, Shin Hwa

1999-01-01

To evaluate functional MR imaging of the motor speech area with and without motor stimulation during the rest period. Nine healthy, right-handed volunteers(M:F=7:2, age:21-40years) were included in this study. Brain activity was mapped using a multislice, gradient echo single shot EPI on a 1.5T MR scanner. The paradigm consisted on a series of alternating rest and activation tasks, performed six times. Each volunteer in the first study(group A) was given examples of motor stimulation during the rest period, while each in the second study(group B) was not given examples of a rest period. Motor stimulation in group A was achieved by continuously flexing five fingers of the right hand. In both groups, maximum internal word generation was achieved during the activation period. Using fMRI analysis software(Stimulate 5.0) and a cross-correlation method(backgroud threshold, 200; correlation threshold, 0.3; ceiling, 1.0; floor, 0.3; minimal count, 3), functional images were analysed. After correlating the activated foci and a time-signal intensity curve, the activated brain cortex and number of pixels were analysed and compared between the two tasks. The t-test was used for statistical analysis. In all nine subjects in group A and B, activation was observed in and adjacent to the left Broca's area. The mean number of activated pixels was 31.6 in group A and 27.8 in group B, a difference which was not statistically significant(P>0.1). Activities in and adjacent to the right Broca's area were seen in seven of group A and four of group B. The mean number of activated pixels was 14.9 in group A and 18 in group B. Eight of nine volunteers in group A showed activity in the left primary motor area with negative correlation to the time-signal intensity curve. The mean number of activated pixels for this group was 17.5. In three volonteers, activation in the right primary motor area was also observed, the mean number of activated pixels in these cases was 10.0. During the rest

Visual-motor integration functioning in a South African middle ...

African Journals Online (AJOL)

Visual-motor integration functioning has been identified as playing an integral role in different aspects of a child's development. Sensory-motor development is not only foundational to the physical maturation process, but is also imperative for progress with formal learning activities. Deficits in visual-motor integration have ...

Correlation analysis of motor current and chatter vibration in grinding using complex continuous wavelet coherence

International Nuclear Information System (INIS)

Liu, Yao; Wang, Xiufeng; Lin, Jing; Zhao, Wei

2016-01-01

Motor current is an emerging and popular signal which can be used to detect machining chatter with its multiple advantages. To achieve accurate and reliable chatter detection using motor current, it is important to make clear the quantitative relationship between motor current and chatter vibration, which has not yet been studied clearly. In this study, complex continuous wavelet coherence, including cross wavelet transform and wavelet coherence, is applied to the correlation analysis of motor current and chatter vibration in grinding. Experimental results show that complex continuous wavelet coherence performs very well in demonstrating and quantifying the intense correlation between these two signals in frequency, amplitude and phase. When chatter occurs, clear correlations in frequency and amplitude in the chatter frequency band appear and the phase difference of current signal to vibration signal turns from random to stable. The phase lead of the most correlated chatter frequency is the largest. With the further development of chatter, the correlation grows up in intensity and expands to higher order chatter frequency band. The analyzing results confirm that there is a consistent correlation between motor current and vibration signals in the grinding chatter process. However, to achieve accurate and reliable chatter detection using motor current, the frequency response bandwidth of current loop of the feed drive system must be wide enough to response chatter effectively. (paper)

Treatment of functional motor disorders

NARCIS (Netherlands)

Gelauff, Jeannette M.; Dreissen, Yasmine E. M.; Tijssen, Marina A. J.; Stone, Jon

OPINION STATEMENT: For the treatment of functional motor disorder, we recommend a three-stage approach. Firstly, patients must be assessed and given an unambiguous diagnosis, with an explanation that helps them understand that they have a genuine disorder, with the potential for reversibility. A key

Use of functional near-infrared spectroscopy to evaluate the effects of anodal transcranial direct current stimulation on brain connectivity in motor-related cortex

Science.gov (United States)

Yan, Jiaqing; Wei, Yun; Wang, Yinghua; Xu, Gang; Li, Zheng; Li, Xiaoli

2015-04-01

Transcranial direct current stimulation (tDCS) is a noninvasive, safe and convenient neuro-modulatory technique in neurological rehabilitation, treatment, and other aspects of brain disorders. However, evaluating the effects of tDCS is still difficult. We aimed to evaluate the effects of tDCS using hemodynamic changes using functional near-infrared spectroscopy (fNIRS). Five healthy participants were employed and anodal tDCS was applied to the left motor-related cortex, with cathodes positioned on the right dorsolateral supraorbital area. fNIRS data were collected from the right motor-related area at the same time. Functional connectivity (FC) between intracortical regions was calculated between fNIRS channels using a minimum variance distortion-less response magnitude squared coherence (MVDR-MSC) method. The levels of Oxy-HbO change and the FC between channels during the prestimulation, stimulation, and poststimulation stages were compared. Results showed no significant level difference, but the FC measured by MVDR-MSC significantly decreased during tDCS compared with pre-tDCS and post-tDCS, although the FC difference between pre-tDCS and post-tDCS was not significant. We conclude that coherence calculated from resting state fNIRS may be a useful tool for evaluating the effects of anodal tDCS and optimizing parameters for tDCS application.

Cerebellar direct current stimulation enhances on-line motor skill acquisition through an effect on accuracy.

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Cantarero, Gabriela; Spampinato, Danny; Reis, Janine; Ajagbe, Loni; Thompson, Tziporah; Kulkarni, Kopal; Celnik, Pablo

2015-02-18

The cerebellum is involved in the update of motor commands during error-dependent learning. Transcranial direct current stimulation (tDCS), a form of noninvasive brain stimulation, has been shown to increase cerebellar excitability and improve learning in motor adaptation tasks. Although cerebellar involvement has been clearly demonstrated in adaptation paradigms, a type of task that heavily relies on error-dependent motor learning mechanisms, its role during motor skill learning, a behavior that likely involves error-dependent as well as reinforcement and strategic mechanisms, is not completely understood. Here, in humans, we delivered cerebellar tDCS to modulate its activity during novel motor skill training over the course of 3 d and assessed gains during training (on-line effects), between days (off-line effects), and overall improvement. We found that excitatory anodal tDCS applied over the cerebellum increased skill learning relative to sham and cathodal tDCS specifically by increasing on-line rather than off-line learning. Moreover, the larger skill improvement in the anodal group was predominantly mediated by reductions in error rate rather than changes in movement time. These results have important implications for using cerebellar tDCS as an intervention to speed up motor skill acquisition and to improve motor skill accuracy, as well as to further our understanding of cerebellar function. Copyright © 2015 the authors 0270-6474/15/353285-06$15.00/0.

Sex differences in anthropometric characteristics, motor and cognitive functioning in preschool children at the time of school enrolment.

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Bala, Gustav; Katić, Ratko

2009-12-01

The study included a sample of 333 preschool children (162 male and 171 female) at the time of school enrolment. Study subjects were recruited from the population of children in kindergartens in the cities of Novi Sad, Sombor, Sremska Mitrovica and Backa Palanka (Province of Voivodina, Serbia). Eight anthropometric variables, seven motor variables and one cognitive variable were analyzed to identify quantitative and qualitative sex differences in anthropometric characteristics, motor and cognitive functioning. Study results showed statistically significant sex differences in anthropometric characteristics and motor abilities in favor of male children, whereas no such difference was recorded in cognitive functioning. Sex differences found in morphological and motor spaces contributed to structuring proper general factors according to space and sex. Somewhat stronger structures were observed in male children. The cognitive aspect of functioning yielded better correlation with motor functioning in female than in male children. Motor functioning correlated better with morphological growth and development in male children, whereas cognitive functioning was relatively independent. These results are not fully in accordance with the current concept of general conditions in preschool children, nor they fully confirm the theory of integral development of children, hence they should be re-examined in future studies. Although these study results cannot be applied to sports practice in general, since we believe that it is too early for preschool children to take up sports and sport competitions, they are relevant for pointing to the need of developing general motor ability and motor behavior in preschool children.

Functional aging impairs the role of feedback in motor learning.

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Liu, Yu; Cao, Chunmei; Yan, Jin H

2013-10-01

Optimal motor skill acquisition frequently requires augmented feedback or knowledge of results (KR). However, the effect of functional declines on the benefits of KR remains to be determined. The objective of this research was to examine how cognitive and motor deficits of older adults influence the use of KR for motor skill learning. A total of 57 older adults (mean 73.1 years; SD 4.2) received both cognitive and eye-hand coordination assessments, whereas 55 young controls (mean 25.8 years; SD 3.8) took only the eye-hand coordination test. All young and older participants learned a time-constrained arm movement through KR in three pre-KR and post-KR intervals. In the subsequent no-KR skill retests, absolute and variable time errors were not significantly reduced for the older learners who had KR during skill practice, especially for those with cognitive and motor dysfunctions. The finding suggests that KR results in no measureable improvement for older adults with cognitive and motor functional deficiencies. More importantly, for the older adults, longer post-KR intervals showed greater detrimental effects on feedback-based motor learning than shorter pauses after KR delivery. The findings support the hypothesis about the effects of cognitive and motor deficits on KR in motor skill learning of older adults. The dynamics of cognitive and motor aging, external feedback and internal control mechanisms collectively explain the deterioration in the sensory-motor learning of older adults. The theoretical implications and practical relevance of functional aging for motor skill learning are discussed. © 2013 Japan Geriatrics Society.

Effects of motor imagery combined with functional electrical stimulation on upper limb motor function of patients with acute ischemic stroke

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Shou-feng LIU

2015-03-01

Full Text Available Objective To explore the effects of motor imagery (MI combined with the third generation functional electrical stimulation (FES on upper limb motor function in acute ischemic stroke patients with hemiplegia.  Methods Forty acute ischemic stroke patients, within 48 h of onset, were randomly divided into FES group (N = 20 and combination group (FES combined with motor imagery, N = 20. All patients received basic routine rehabilitation training, for example, good limb positioning, accepting braces, balance training and training in the activities of daily living (ADL. FES group received the third generation FES therapy and the combination group also received motor imagery for 2 weeks. All of the patients were assessed with Fugl-Meyer Assessment (FMA, Action Research Arm Test (ARAT and active range of motion (AROM of wrist dorsiflexion before and after 2 weeks of treatment.  Results After 2 weeks of treatment, the 2 groups had significantly higher FMA score, ARAT score and AROM of wrist dorsiflexion than that in pre-treatment (P = 0.000, for all. Besides, the FMA score (t = - 2.528, P = 0.016, ARAT score (t = - 2.562, P = 0.014 and AROM of wrist dorsiflexion (t = - 2.469, P = 0.018 in the combination group were significantly higher than that in the FES group. There were interactions of treatment methods with observation time points (P < 0.05, for all.  Conclusions Motor imagery combined with the third generation FES can effectively promote the recovery of upper limb motor function and motion range of wrist dorsiflexion in patients with acute ischemic stroke. DOI: 10.3969/j.issn.1672-6731.2015.03.008

Relationship between functional connectivity and motor function assessment in stroke patients with hemiplegia: a resting-state functional MRI study

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Zhang, Ye; Wang, Li; Zhang, Jingna; Sang, Linqiong; Li, Pengyue; Qiu, Mingguo [Third Military Medical University, Department of Medical Imaging, College of Biomedical Engineering, Chongqing (China); Liu, Hongliang; Yan, Rubing [Third Military Medical University, Department of Rehabilitation, Southwest Hospital, Chongqing (China); Yang, Jun; Wang, Jian [Third Military Medical University, Department of Radiology, Southwest Hospital, Chongqing (China)

2016-05-15

Resting-state functional magnetic resonance imaging (fMRI) has been used to examine the brain mechanisms of stroke patients with hemiplegia, but the relationship between functional connectivity (FC) and treatment-induced motor function recovery has not yet been fully investigated. This study aimed to identify the brain FC changes in stroke patients and study the relationship between FC and motor function assessment using the resting-state fMRI. Seventeen stroke patients with hemiplegia and fifteen healthy control subjects (HCSs) were recruited in this study. We compared the FC between the ipsilesional primary motor cortex (M1) and the whole brain of the patients with the FC of the HCSs and studied the FC changes in the patients before and after conventional rehabilitation and motor imagery therapy. Additionally, correlations between the FC change and motor function of the patients were studied. Compared to the HCSs, the FC in the patient group was significantly increased between the ipsilesional M1 and the ipsilesional inferior parietal cortex, frontal gyrus, supplementary motor area (SMA), and contralesional angular and decreased between the ipsilesional M1 and bilateral M1. After the treatment, the FC between the ipsilesional M1 and contralesional M1 increased while the FC between the ipsilesional M1 and ipsilesional SMA and paracentral lobule decreased. A statistically significant correlation was found between the FC change in the bilateral M1 and the Fugl-Meyer assessment (FMA) score change. Our results revealed an abnormal motor network after stroke and suggested that the FC could serve as a biomarker of motor function recovery in stroke patients with hemiplegia. (orig.)

Relationship between functional connectivity and motor function assessment in stroke patients with hemiplegia: a resting-state functional MRI study

International Nuclear Information System (INIS)

Zhang, Ye; Wang, Li; Zhang, Jingna; Sang, Linqiong; Li, Pengyue; Qiu, Mingguo; Liu, Hongliang; Yan, Rubing; Yang, Jun; Wang, Jian

2016-01-01

Resting-state functional magnetic resonance imaging (fMRI) has been used to examine the brain mechanisms of stroke patients with hemiplegia, but the relationship between functional connectivity (FC) and treatment-induced motor function recovery has not yet been fully investigated. This study aimed to identify the brain FC changes in stroke patients and study the relationship between FC and motor function assessment using the resting-state fMRI. Seventeen stroke patients with hemiplegia and fifteen healthy control subjects (HCSs) were recruited in this study. We compared the FC between the ipsilesional primary motor cortex (M1) and the whole brain of the patients with the FC of the HCSs and studied the FC changes in the patients before and after conventional rehabilitation and motor imagery therapy. Additionally, correlations between the FC change and motor function of the patients were studied. Compared to the HCSs, the FC in the patient group was significantly increased between the ipsilesional M1 and the ipsilesional inferior parietal cortex, frontal gyrus, supplementary motor area (SMA), and contralesional angular and decreased between the ipsilesional M1 and bilateral M1. After the treatment, the FC between the ipsilesional M1 and contralesional M1 increased while the FC between the ipsilesional M1 and ipsilesional SMA and paracentral lobule decreased. A statistically significant correlation was found between the FC change in the bilateral M1 and the Fugl-Meyer assessment (FMA) score change. Our results revealed an abnormal motor network after stroke and suggested that the FC could serve as a biomarker of motor function recovery in stroke patients with hemiplegia. (orig.)

Brief Assessment of Motor Function: Content Validity and Reliability of the Upper Extremity Gross Motor Scale

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Cintas, Holly Lea; Parks, Rebecca; Don, Sarah; Gerber, Lynn

2011-01-01

Content validity and reliability of the Brief Assessment of Motor Function (BAMF) Upper Extremity Gross Motor Scale (UEGMS) were evaluated in this prospective, descriptive study. The UEGMS is one of five BAMF ordinal scales designed for quick documentation of gross, fine, and oral motor skill levels. Designed to be independent of age and…

Functional Neuroimaging of Motor Control inParkinson’s Disease

DEFF Research Database (Denmark)

Herz, Damian M; Eickhoff, Simon B; Løkkegaard, Annemette

2014-01-01

Functional neuroimaging has been widely used to study the activation patterns of the motor network in patients with Parkinson's disease (PD), but these studies have yielded conflicting results. This meta-analysis of previous neuroimaging studies was performed to identify patterns of abnormal...... movement-related activation in PD that were consistent across studies. We applied activation likelihood estimation (ALE) of functional neuroimaging studies probing motor function in patients with PD. The meta-analysis encompassed data from 283 patients with PD reported in 24 functional neuroimaging studies...

BDNF genotype interacts with motor-function to influence rehabilitation responsiveness post-stroke

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Christine T Shiner

2016-05-01

Full Text Available Background. Persistent motor impairment is common but highly heterogeneous post-stroke. Genetic polymorphisms, including those identified on the brain derived neurotrophic factor (BDNF and apolipoprotein E (APOE genes, may contribute to this variability by limiting the capacity for use-dependent neuroplasticity, and hence rehabilitation responsiveness.Objective. To determine whether BDNF and APOE genotypes influence motor improvement facilitated by post-stroke upper-limb rehabilitation. Methods. BDNF Val66Met and APOE isoform genotypes were determined using leukocyte DNA for 55 community-dwelling patients 2-123 months post-stroke. All patients completed a dose-matched upper-limb rehabilitation program of either Wii-based Movement Therapy or Constraint-induced Movement Therapy. Upper-limb motor-function was assessed pre- and post-therapy using a suite of functional measures. Results. Motor-function improved for all patients post-therapy, with no difference between therapy groups. In the pooled data, there was no significant effect of BDNF or APOE genotype on motor-function at baseline, or following the intervention. However, a significant interaction between the level of residual motor-function and BDNF genotype was identified (p=0.029, whereby post-therapy improvement was significantly less for Met allele carriers with moderate and high, but not low motor-function. There was no significant association between APOE genotype and therapy outcomes. Conclusions. This study identified a novel interaction between the BDNF Val66Met polymorphism, motor-function status and the magnitude of improvement with rehabilitation in chronic stroke. This polymorphism does not preclude, but may reduce, the magnitude of motor improvement with therapy, particularly for patients with higher but not lower residual motor-function. BDNF genotype should be considered in the design and interpretation of clinical trials.

Repeated sessions of noninvasive brain DC stimulation is associated with motor function improvement in stroke patients.

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Boggio, Paulo S; Nunes, Alice; Rigonatti, Sergio P; Nitsche, Michael A; Pascual-Leone, Alvaro; Fregni, Felipe

2007-01-01

Recent evidence has suggested that a simple technique of noninvasive brain stimulation - transcranial direct current stimulation (tDCS) - is associated with a significant motor function improvement in stroke patients. We tested the motor performance improvement in stroke patients following 4 weekly sessions of sham, anodal- and cathodal tDCS (experiment 1) and the effects of 5 consecutive daily sessions of cathodal tDCS (experiment 2). A blinded rater evaluated motor function using the Jebsen-Taylor Hand Function Test. There was a significant main effect of stimulation condition (p=0.009) in experiment 1. Furthermore there was a significant motor function improvement after either cathodal tDCS of the unaffected hemisphere (p=0.016) or anodal tDCS of the affected hemisphere (p=0.046) when compared to sham tDCS. There was no cumulative effect associated with weekly sessions of tDCS, however consecutive daily sessions of tDCS (experiment 2) were associated with a significant effect on time (pmotor function improvement in stroke patients; and support that consecutive daily sessions of tDCS might increase its behavioral effects. Because the technique of tDCS is simple, safe and non-expensive; our findings support further research on the use of this technique for the rehabilitation of patients with stroke.

Motor functions and adaptive behaviour in children with childhood apraxia of speech.

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Tükel, Şermin; Björelius, Helena; Henningsson, Gunilla; McAllister, Anita; Eliasson, Ann Christin

2015-01-01

Undiagnosed motor and behavioural problems have been reported for children with childhood apraxia of speech (CAS). This study aims to understand the extent of these problems by determining the profile of and relationships between speech/non-speech oral, manual and overall body motor functions and adaptive behaviours in CAS. Eighteen children (five girls and 13 boys) with CAS, 4 years 4 months to 10 years 6 months old, participated in this study. The assessments used were the Verbal Motor Production Assessment for Children (VMPAC), Bruininks-Oseretsky Test of Motor Proficiency (BOT-2) and Adaptive Behaviour Assessment System (ABAS-II). Median result of speech/non-speech oral motor function was between -1 and -2 SD of the mean VMPAC norms. For BOT-2 and ABAS-II, the median result was between the mean and -1 SD of test norms. However, on an individual level, many children had co-occurring difficulties (below -1 SD of the mean) in overall and manual motor functions and in adaptive behaviour, despite few correlations between sub-tests. In addition to the impaired speech motor output, children displayed heterogeneous motor problems suggesting the presence of a global motor deficit. The complex relationship between motor functions and behaviour may partly explain the undiagnosed developmental difficulties in CAS.

Disentangling the relationship between children's motor ability, executive function and academic achievement.

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Mirko Schmidt

Full Text Available Even though positive relations between children's motor ability and their academic achievement are frequently reported, the underlying mechanisms are still unclear. Executive function has indeed been proposed, but hardly tested as a potential mediator. The aim of the present study was therefore to examine the mediating role of executive function in the relationship between motor ability and academic achievement, also investigating the individual contribution of specific motor abilities to the hypothesized mediated linkage to academic achievement. At intervals of ten weeks, 236 children aged between 10 and 12 years were tested in terms of their motor ability (t1: cardiovascular endurance, muscular strength, motor coordination, core executive functions (t2: updating, inhibition, shifting, and academic achievement (t3: mathematics, reading, spelling. Structural equation modelling revealed executive function to be a mediator in the relation between motor ability and academic achievement, represented by a significant indirect effect. In separate analyses, each of the three motor abilities were positively related to children's academic achievement. However, only in the case of children's motor coordination, the mediation by executive function accounted for a significance percentage of variance of academic achievement data. The results provide evidence in support of models that conceive executive function as a mechanism explaining the relationship that links children's physical activity-related outcomes to academic achievement and strengthen the advocacy for quality physical activity not merely focused on health-related physical fitness outcomes, but also on motor skill development and learning.

The Gemin associates of survival motor neuron are required for motor function in Drosophila.

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Borg, Rebecca; Cauchi, Ruben J

2013-01-01

Membership of the survival motor neuron (SMN) complex extends to nine factors, including the SMN protein, the product of the spinal muscular atrophy (SMA) disease gene, Gemins 2-8 and Unrip. The best-characterised function of this macromolecular machine is the assembly of the Sm-class of uridine-rich small nuclear ribonucleoprotein (snRNP) particles and each SMN complex member has a key role during this process. So far, however, only little is known about the function of the individual Gemin components in vivo. Here, we make use of the Drosophila model organism to uncover loss-of-function phenotypes of Gemin2, Gemin3 and Gemin5, which together with SMN form the minimalistic fly SMN complex. We show that ectopic overexpression of the dead helicase Gem3(ΔN) mutant or knockdown of Gemin3 result in similar motor phenotypes, when restricted to muscle, and in combination cause lethality, hence suggesting that Gem3(ΔN) overexpression mimics a loss-of-function. Based on the localisation pattern of Gem3(ΔN), we predict that the nucleus is the primary site of the antimorphic or dominant-negative mechanism of Gem3(ΔN)-mediated interference. Interestingly, phenotypes induced by human SMN overexpression in Drosophila exhibit similarities to those induced by overexpression of Gem3(ΔN). Through enhanced knockdown we also uncover a requirement of Gemin2, Gemin3 and Gemin5 for viability and motor behaviour, including locomotion as well as flight, in muscle. Notably, in the case of Gemin3 and Gemin5, such function also depends on adequate levels of the respective protein in neurons. Overall, these findings lead us to speculate that absence of any one member is sufficient to arrest the SMN-Gemins complex function in a nucleocentric pathway, which is critical for motor function in vivo.

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

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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. PMID:24994971

Current status of gene therapy for motor neuron disease

Institute of Scientific and Technical Information of China (English)

Xingkai An; Rong Peng; Shanshan Zhao

2006-01-01

OBJECTIVE: Although the etiology and pathogenesis of motor neuron disease is still unknown, there are many hypotheses on motor neuron mitochondrion, cytoskeleton structure and functional injuries. Thus, gene therapy of motor neuron disease has become a hot topic to apply in viral vector, gene delivery and basic gene techniques.DATA SOURCES: The related articles published between January 2000 and October 2006 were searched in Medline database and ISl database by computer using the keywords "motor neuron disease, gene therapy", and the language is limited to English. Meanwhile, the related references of review were also searched by handiwork. STUDY SELECTION: Original articles and referred articles in review were chosen after first hearing, then the full text which had new ideas were found, and when refer to the similar study in the recent years were considered first.DATA EXTRACTION: Among the 92 related articles, 40 ones were accepted, and 52 were excluded because of repetitive study or reviews.DATA SYNTHESIS: The viral vectors of gene therapy for motor neuron disease include adenoviral, adeno-associated viral vectors, herpes simplex virus type 1 vectors and lentiviral vectors. The delivery of them can be achieved by direct injection into the brain, or by remote delivery after injection vectors into muscle or peripheral nerves, or by ex vivo gene transfer. The viral vectors of gene therapy for motor neuron disease have been successfully developed, but the gene delivery of them is hampered by some difficulties. The RNA interference and neuroprotection are the main technologies for gene-based therapy in motor neuron disease. CONCLUSION : The RNA interference for motor neuron disease has succeeded in animal models, and the neuroprotection also does. But, there are still a lot of questions for gene therapy in the clinical treatment of motor neuron disease.

Double-temperature ratchet model and current reversal of coupled Brownian motors

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Li, Chen-Pu; Chen, Hong-Bin; Zheng, Zhi-Gang

2017-12-01

On the basis of the transport features and experimental phenomena observed in studies of molecular motors, we propose a double-temperature ratchet model of coupled motors to reveal the dynamical mechanism of cooperative transport of motors with two heads, where the interactions and asynchrony between two motor heads are taken into account. We investigate the collective unidirectional transport of coupled system and find that the direction of motion can be reversed under certain conditions. Reverse motion can be achieved by modulating the coupling strength, coupling free length, and asymmetric coefficient of the periodic potential, which is understood in terms of the effective potential theory. The dependence of the directed current on various parameters is studied systematically. Directed transport of coupled Brownian motors can be manipulated and optimized by adjusting the pulsation period or the phase shift of the pulsation temperature.

Forced, not voluntary, exercise improves motor function in Parkinson's disease patients.

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Ridgel, Angela L; Vitek, Jerrold L; Alberts, Jay L

2009-01-01

Animal studies indicate forced exercise (FE) improves overall motor function in Parkinsonian rodents. Global improvements in motor function following voluntary exercise (VE) are not widely reported in human Parkinson's disease (PD) patients. The aim of this study was to compare the effects of VE and FE on PD symptoms, motor function, and bimanual dexterity. Ten patients with mild to moderate PD were randomly assigned to complete 8 weeks of FE or VE. With the assistance of a trainer, patients in the FE group pedaled at a rate 30% greater than their preferred voluntary rate, whereas patients in the VE group pedaled at their preferred rate. Aerobic intensity for both groups was identical, 60% to 80% of their individualized training heart rate. Aerobic fitness improved for both groups. Following FE, Unified Parkinson's Disease Rating Scale (UPDRS) motor scores improved 35%, whereas patients completing VE did not exhibit any improvement. The control and coordination of grasping forces during the performance of a functional bimanual dexterity task improved significantly for patients in the FE group, whereas no changes in motor performance were observed following VE. Improvements in clinical measures of rigidity and bradykinesia and biomechanical measures of bimanual dexterity were maintained 4 weeks after FE cessation. Aerobic fitness can be improved in PD patients following both VE and FE interventions. However, only FE results in significant improvements in motor function and bimanual dexterity. Biomechanical data indicate that FE leads to a shift in motor control strategy, from feedback to a greater reliance on feedforward processes, which suggests FE may be altering central motor control processes.

Statistical mechanical characteristics of slip-ring induction motors when direct current braking

Energy Technology Data Exchange (ETDEWEB)

Kedzior, W; Muchorowski, J; Pienkowski, K

1980-09-01

This paper evaluates methods of braking high capacity belt conveyors used in brown coal surface mines in Poland. Complications associated with belt conveyor braking, particularly when a conveyor moves down a slope, are analyzed. A method of calculating mechanical characteristics of wound-rotor induction motors during direct current braking taking into account saturation of magnetic circuit is presented. Characteristics of the SZUr motor with 630 kW power, used in brown coal mining, are also given. Analyses show that motor operation can be efficiently braked in two ways: 1. by changing additional resistance in rotor circuit (e.g. using thyristor controller); 2. by changing intensity of electric current supplied to stator winding (e.g. using a rectifier). (3 refs.) (In Polish)

The single- and double-particle properties and the current reversal of coupled Brownian motors

International Nuclear Information System (INIS)

Li, Chen-Pu; Chen, Hong-Bin; Zheng, Zhi-Gang; Fan, Hong; Shen, Wen-Mei

2017-01-01

In this paper, we investigate the directed transport of coupled Brownian motors composed of two identical particles which is individually subject to a time-symmetric rocking force in spatially-symmetric periodic potentials. We find that both the coupling free length and the coupling strength can induce the reversed motion of the coupled Brownian motors, the essence of which is the coupled Brownian motors can exhibit completely different single- or double-particle properties under certain conditions. Namely, the current reversal is the result of the mutual conversion between the single- and double-particle properties of the coupled Brownian motors. Moreover, the directed current of coupled Brownian motors can be optimized and manipulated by adjusting the strength, the period, the phase difference of the rocking forces, and the noise intensity. (paper)

Enhanced motor skill acquisition in the non-dominant upper extremity using intermittent theta burst stimulation and transcranial direct current stimulation.

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Butts, Raymond J; Kolar, Melissa B; Newman-Norlund, Roger D

2014-01-01

Individuals suffering from motor impairments often require physical therapy (PT) to help improve their level of function. Previous investigations suggest that both intermittent theta burst stimulation (iTBS) and bihemispheric transcranial direct current stimulation (tDCS) may increase the speed and extent of motor learning/relearning. The purpose of the current study was to explore the feasibility and effectiveness of a novel, non-invasive brain stimulation approach that combined an iTBS primer, and bihemispheric stimulation coupled with motor training. We hypothesized that individuals exposed to this novel treatment would make greater functional improvements than individuals undergoing sham stimulation when tested immediately following, 24-h, and 7-days post-training. A total of 26 right-handed, healthy young adults were randomly assigned to either a treatment (n = 15) or control group (n = 12). iTBS (20 trains of 10 pulse triplets each delivered at 80% active motor threshold (AMT) / 50 Hz over 191.84 s) and bihemispheric tDCS (1.0 ma for 20 min) were used as a primer to, and in conjunction with, 20 min of motor training, respectively. Our primary outcome measure was performance on the Jebsen-Taylor Hand Function (JTHF) test. Participants tolerated the combined iTBS/bihemispheric stimulation treatment without complaint. While performance gains in the sham and stimulation group were not significant immediately after training, they were nearly significant 24-h post training (p = 0.055), and were significant at 7-days post training (p iTBS/bihemispheric stimulation protocol is both feasible and effective. Future research should examine the mechanistic explanation of this approach as well as the potential of using this approach in clinical populations.

Transcranial direct current stimulation over multiple days enhances motor performance of a grip task.

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Fan, Julie; Voisin, Julien; Milot, Marie-Hélène; Higgins, Johanne; Boudrias, Marie-Hélène

2017-09-01

Recovery of handgrip is critical after stroke since it is positively related to upper limb function. To boost motor recovery, transcranial direct current stimulation (tDCS) is a promising, non-invasive brain stimulation technique for the rehabilitation of persons with stroke. When applied over the primary motor cortex (M1), tDCS has been shown to modulate neural processes involved in motor learning. However, no studies have looked at the impact of tDCS on the learning of a grip task in both stroke and healthy individuals. To assess the use of tDCS over multiple days to promote motor learning of a grip task using a learning paradigm involving a speed-accuracy tradeoff in healthy individuals. In a double-blinded experiment, 30 right-handed subjects (mean age: 22.1±3.3 years) participated in the study and were randomly assigned to an anodal (n=15) or sham (n=15) stimulation group. First, subjects performed the grip task with their dominant hand while following the pace of a metronome. Afterwards, subjects trained on the task, at their own pace, over 5 consecutive days while receiving sham or anodal tDCS over M1. After training, subjects performed de novo the metronome-assisted task. The change in performance between the pre and post metronome-assisted task was used to assess the impact of the grip task and tDCS on learning. Anodal tDCS over M1 had a significant effect on the speed-accuracy tradeoff function. The anodal tDCS group showed significantly greater improvement in performance (39.28±15.92%) than the sham tDCS group (24.06±16.35%) on the metronome-assisted task, t(28)=2.583, P=0.015 (effect size d=0.94). Anodal tDCS is effective in promoting grip motor learning in healthy individuals. Further studies are warranted to test its potential use for the rehabilitation of fine motor skills in stroke patients. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The relationship between motor function, cognition, independence and quality of life in myelomeningocele patients.

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Luz, Carolina Lundberg; Moura, Maria Clara Drummond Soares de; Becker, Karine Kyomi; Teixeira, Rosani Aparecida Antunes; Voos, Mariana Callil; Hasue, Renata Hydee

2017-08-01

Motor function, cognition, functional independence and quality of life have been described in myelomeningocele patients, but no study has investigated their relationships. We aimed to investigate the relationships between motor function, cognition, functional independence, quality of life, age, and lesion level in myelomeningocele patients, and investigate the influence of hydrocephalus on these variables. We assessed 47 patients with the Gross Motor Function Measure (motor function), Raven's Colored Progressive Matrices (cognition), Pediatric Evaluation of Disability Inventory (functional independence) and the Autoquestionnaire Qualité de vie Enfant Imagé (quality of life). Spearman's correlation tests determined relationships between the variables. The Friedman ANOVAs determined the influence of hydrocephalus. Motor function was strongly related to mobility and lesion level, and moderately related to cognition, self-care and social function. Cognition and quality of life were moderately related to functional independence. Age correlated moderately with functional independence and quality of life. Hydrocephalus resulted in poorer motor/cognitive outcomes and lower functional independence.

Parallel Alterations of Functional Connectivity during Execution and Imagination after Motor Imagery Learning

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Zhang, Rushao; Hui, Mingqi; Long, Zhiying; Zhao, Xiaojie; Yao, Li

2012-01-01

Background Neural substrates underlying motor learning have been widely investigated with neuroimaging technologies. Investigations have illustrated the critical regions of motor learning and further revealed parallel alterations of functional activation during imagination and execution after learning. However, little is known about the functional connectivity associated with motor learning, especially motor imagery learning, although benefits from functional connectivity analysis attract more attention to the related explorations. We explored whether motor imagery (MI) and motor execution (ME) shared parallel alterations of functional connectivity after MI learning. Methodology/Principal Findings Graph theory analysis, which is widely used in functional connectivity exploration, was performed on the functional magnetic resonance imaging (fMRI) data of MI and ME tasks before and after 14 days of consecutive MI learning. The control group had no learning. Two measures, connectivity degree and interregional connectivity, were calculated and further assessed at a statistical level. Two interesting results were obtained: (1) The connectivity degree of the right posterior parietal lobe decreased in both MI and ME tasks after MI learning in the experimental group; (2) The parallel alterations of interregional connectivity related to the right posterior parietal lobe occurred in the supplementary motor area for both tasks. Conclusions/Significance These computational results may provide the following insights: (1) The establishment of motor schema through MI learning may induce the significant decrease of connectivity degree in the posterior parietal lobe; (2) The decreased interregional connectivity between the supplementary motor area and the right posterior parietal lobe in post-test implicates the dissociation between motor learning and task performing. These findings and explanations further revealed the neural substrates underpinning MI learning and supported that

Infant motor and cognitive abilities and subsequent executive function.

Science.gov (United States)

Wu, Meng; Liang, Xi; Lu, Shan; Wang, Zhengyan

2017-11-01

Although executive function (EF) is widely considered crucial to several aspects of life, the mechanisms underlying EF development remain largely unexplored, especially for infants. From a behavioral or neurodevelopmental perspective, motor and general cognitive abilities are linked with EF. EF development is a multistage process that starts with sensorimotor interactive behaviors, which become basic cognitive abilities and, in turn, mature EF. This study aims to examine how infant motor and general cognitive abilities are linked with their EF at 3 years of age. This work also aims to explore the potential processes of EF development from early movement. A longitudinal study was conducted with 96 infants (55 girls and 41 boys). The infants' motor and general cognitive abilities were assessed at 1 and 2 years of age with Bayley Scales of Infant and Toddler Development, Second and Third Editions, respectively. Infants' EFs were assessed at 3 years of age with Working Memory Span task, Day-Night task, Wrapped Gift task, and modified Gift-in-Bag task. Children with higher scores for cognitive ability at 2 years of age performed better in working memory, and children with higher scores for gross motor ability at 2 years performed better in cognitive inhibitory control (IC). Motor ability at 1 year and fine/gross motor ability at 2 years indirectly affected cognitive IC via general cognitive ability at 2 years and working memory. EF development is a multistage process that originates from physical movement to simple cognitive function, and then to complex cognitive function. Infants and toddlers can undergo targeted motor training to promote EF development. Copyright © 2017 Elsevier Inc. All rights reserved.

Transcranial direct current stimulation (tDCS) to the supplementary motor area (SMA) influences performance on motor tasks.

Science.gov (United States)

Hupfeld, K E; Ketcham, C J; Schneider, H D

2017-03-01

The supplementary motor area (SMA) is believed to be highly involved in the planning and execution of both simple and complex motor tasks. This study aimed to examine the role of the SMA in planning the movements required to complete reaction time, balance, and pegboard tasks using anodal transcranial direct current stimulation (tDCS), which passes a weak electrical current between two electrodes, in order to modulate neuronal activity. Twenty healthy adults were counterbalanced to receive either tDCS (experimental condition) or no tDCS (control condition) for 3 days. During administration of tDCS, participants performed a balance task significantly faster than controls. After tDCS, subjects significantly improved their simple and choice reaction time. These results demonstrate that the SMA is highly involved in planning and executing fine and gross motor skill tasks and that tDCS is an effective modality for increasing SMA-related performance on these tasks. The findings may be generalizable and therefore indicate implications for future interventions using tDCS as a therapeutic tool.

Motor imagery learning modulates functional connectivity of multiple brain systems in resting state.

Science.gov (United States)

Zhang, Hang; Long, Zhiying; Ge, Ruiyang; Xu, Lele; Jin, Zhen; Yao, Li; Liu, Yijun

2014-01-01

Learning motor skills involves subsequent modulation of resting-state functional connectivity in the sensory-motor system. This idea was mostly derived from the investigations on motor execution learning which mainly recruits the processing of sensory-motor information. Behavioral evidences demonstrated that motor skills in our daily lives could be learned through imagery procedures. However, it remains unclear whether the modulation of resting-state functional connectivity also exists in the sensory-motor system after motor imagery learning. We performed a fMRI investigation on motor imagery learning from resting state. Based on previous studies, we identified eight sensory and cognitive resting-state networks (RSNs) corresponding to the brain systems and further explored the functional connectivity of these RSNs through the assessments, connectivity and network strengths before and after the two-week consecutive learning. Two intriguing results were revealed: (1) The sensory RSNs, specifically sensory-motor and lateral visual networks exhibited greater connectivity strengths in precuneus and fusiform gyrus after learning; (2) Decreased network strength induced by learning was proved in the default mode network, a cognitive RSN. These results indicated that resting-state functional connectivity could be modulated by motor imagery learning in multiple brain systems, and such modulation displayed in the sensory-motor, visual and default brain systems may be associated with the establishment of motor schema and the regulation of introspective thought. These findings further revealed the neural substrates underlying motor skill learning and potentially provided new insights into the therapeutic benefits of motor imagery learning.

Obesity Reduces Cognitive and Motor Functions across the Lifespan

OpenAIRE

Wang, Chuanming; Chan, John S. Y.; Ren, Lijie; Yan, Jin H.

2016-01-01

Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has ...

Motor function deficits in schizophrenia: an fMRI and VBM study

Energy Technology Data Exchange (ETDEWEB)

Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Singh, Namita; Khushu, Subash [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Center, Delhi (India); Goyal, Satnam; Bhatia, Triptish; Deshpande, Smita N. [RML Hospital, PGIMER, New Delhi (India)

2014-05-15

To investigate whether the motor functional alterations in schizophrenia (SZ) are also associated with structural changes in the related brain areas using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). A sample of 14 right-handed SZ patients and 14 right-handed healthy control subjects matched for age, sex, and education were examined with structural high-resolution T1-weighted MRI; fMRI images were obtained during right index finger-tapping task in the same session. fMRI results showed reduced functional activation in the motor areas (contralateral precentral and postcentral gyrus) and ipsilateral cerebellum in SZ subjects as compared to healthy controls (n = 14). VBM analysis also revealed reduced grey matter in motor areas and white matter reduction in cerebellum of SZ subjects as compared to controls. The present study provides an evidence for a possible association between structural alterations in the motor cortex and disturbed functional activation in the motor areas in persons affected with SZ during a simple finger-tapping task. (orig.)

Motor function deficits in schizophrenia: an fMRI and VBM study

International Nuclear Information System (INIS)

Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Singh, Namita; Khushu, Subash; Goyal, Satnam; Bhatia, Triptish; Deshpande, Smita N.

2014-01-01

To investigate whether the motor functional alterations in schizophrenia (SZ) are also associated with structural changes in the related brain areas using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). A sample of 14 right-handed SZ patients and 14 right-handed healthy control subjects matched for age, sex, and education were examined with structural high-resolution T1-weighted MRI; fMRI images were obtained during right index finger-tapping task in the same session. fMRI results showed reduced functional activation in the motor areas (contralateral precentral and postcentral gyrus) and ipsilateral cerebellum in SZ subjects as compared to healthy controls (n = 14). VBM analysis also revealed reduced grey matter in motor areas and white matter reduction in cerebellum of SZ subjects as compared to controls. The present study provides an evidence for a possible association between structural alterations in the motor cortex and disturbed functional activation in the motor areas in persons affected with SZ during a simple finger-tapping task. (orig.)

Organization of the human motor system as studied by functional magnetic resonance imaging

International Nuclear Information System (INIS)

Mattay, Venkata S.; Weinberger, Daniel R.

1999-01-01

Blood oxygenation level dependent functional magnetic resonance imaging (BOLD fMRI), because of its superior resolution and unlimited repeatability, can be particularly useful in studying functional aspects of the human motor system, especially plasticity, and somatotopic and temporal organization. In this survey, while describing studies that have reliably used BOLD fMRI to examine these aspects of the motor system, we also discuss studies that investigate the neural substrates underlying motor skill acquisition, motor imagery, production of motor sequences; effect of rate and force of movement on brain activation and hemispheric control of motor function. In the clinical realm, in addition to the presurgical evaluation of neurosurgical patients, BOLD fMRI has been used to explore the mechanisms underlying motor abnormalities in patients with neuropsychiatric disorders and the mechanisms underlying reorganization or plasticity of the motor system following a cerebral insult

Development of the pump protection system against cavitation on the basis of the stator current signature analysis of drive electric motor

Science.gov (United States)

Kipervasser, M. V.; Gerasimuk, A. V.; Simakov, V. P.

2018-05-01

In the present paper a new registration method of such inadmissible phenomenon as cavitation in the operating mode of centrifugal pump is offered. Influence of cavitation and extent of its development on the value of mechanical power consumed by the pump from the electric motor is studied. On the basis of design formulas the joint mathematical model of centrifugal pumping unit with the synchronous motor is created. In the model the phenomena accompanying the work of a pumping installation in the cavitation mode are considered. Mathematical modeling of the pump operation in the considered emergency operation is carried out. The chart of stator current of the electric motor, depending on the degree of cavitation development of is received. On the basis of the analysis of the obtained data the conclusion on the possibility of registration of cavitation by the current of drive electric motor is made and the functional diagram of the developed protection system is offered, its operation principle is described.

Exercise alters resting state functional connectivity of motor circuits in Parkinsonian rats

Science.gov (United States)

Wang, Zhuo; Guo, Yumei; Myers, Kalisa G.; Heintz, Ryan; Peng, Yu-Hao; Maarek, Jean-Michel I.; Holschneider, Daniel P.

2014-01-01

Few studies have examined changes in functional connectivity after long-term aerobic exercise. We examined the effects of 4 weeks of forced running wheel exercise on the resting-state functional connectivity (rsFC) of motor circuits of rats subjected to bilateral 6-hydroxydopamine lesion of the dorsal striatum. Our results showed substantial similarity between lesion-induced changes in rsFC in the rats and alterations in rsFC reported in Parkinson’s disease subjects, including disconnection of the dorsolateral striatum. Exercise in lesioned rats resulted in: (a) normalization of many of the lesion-induced alterations in rsFC, including reintegration of the dorsolateral striatum into the motor network; (b) emergence of the ventrolateral striatum as a new broadly connected network hub; (c) increased rsFC among the motor cortex, motor thalamus, basal ganglia, and cerebellum. Our results showed for the first time that long-term exercise training partially reversed lesion-induced alterations in rsFC of the motor circuits, and in addition enhanced functional connectivity in specific motor pathways in the Parkinsonian rats, which could underlie recovery in motor functions observed in these rats. PMID:25219465

Effect of sensory and motor connectivity on hand function in pediatric hemiplegia.

Science.gov (United States)

Gupta, Disha; Barachant, Alexandre; Gordon, Andrew M; Ferre, Claudio; Kuo, Hsing-Ching; Carmel, Jason B; Friel, Kathleen M

2017-11-01

We tested the hypothesis that somatosensory system injury would more strongly affect movement than motor system injury in children with unilateral cerebral palsy (USCP). This hypothesis was based on how somatosensory and corticospinal circuits adapt to injury during development; whereas the motor system can maintain connections to the impaired hand from the uninjured hemisphere, this does not occur in the somatosensory system. As a corollary, cortical injury strongly impairs sensory function, so we hypothesized that cortical lesions would impair hand function more than subcortical lesions. Twenty-four children with unilateral cerebral palsy had physiological and anatomical measures of the motor and somatosensory systems and lesion classification. Motor physiology was performed with transcranial magnetic stimulation and somatosensory physiology with vibration-evoked electroencephalographic potentials. Tractography of the corticospinal tract and the medial lemniscus was performed with diffusion tensor imaging, and lesions were classified by magnetic resonance imaging. Anatomical and physiological results were correlated with measures of hand function using 2 independent statistical methods. Children with disruptions in the somatosensory connectivity and cortical lesions had the most severe upper extremity impairments, particularly somatosensory function. Motor system connectivity was significantly correlated with bimanual function, but not unimanual function or somatosensory function. Both sensory and motor connectivity impact hand function in children with USCP. Somatosensory connectivity could be an important target for recovery of hand function in children with USCP. Ann Neurol 2017;82:766-780. © 2017 American Neurological Association.

Motor Imagery Learning Modulates Functional Connectivity of Multiple Brain Systems in Resting State

Science.gov (United States)

Zhang, Hang; Long, Zhiying; Ge, Ruiyang; Xu, Lele; Jin, Zhen; Yao, Li; Liu, Yijun

2014-01-01

Background Learning motor skills involves subsequent modulation of resting-state functional connectivity in the sensory-motor system. This idea was mostly derived from the investigations on motor execution learning which mainly recruits the processing of sensory-motor information. Behavioral evidences demonstrated that motor skills in our daily lives could be learned through imagery procedures. However, it remains unclear whether the modulation of resting-state functional connectivity also exists in the sensory-motor system after motor imagery learning. Methodology/Principal Findings We performed a fMRI investigation on motor imagery learning from resting state. Based on previous studies, we identified eight sensory and cognitive resting-state networks (RSNs) corresponding to the brain systems and further explored the functional connectivity of these RSNs through the assessments, connectivity and network strengths before and after the two-week consecutive learning. Two intriguing results were revealed: (1) The sensory RSNs, specifically sensory-motor and lateral visual networks exhibited greater connectivity strengths in precuneus and fusiform gyrus after learning; (2) Decreased network strength induced by learning was proved in the default mode network, a cognitive RSN. Conclusions/Significance These results indicated that resting-state functional connectivity could be modulated by motor imagery learning in multiple brain systems, and such modulation displayed in the sensory-motor, visual and default brain systems may be associated with the establishment of motor schema and the regulation of introspective thought. These findings further revealed the neural substrates underlying motor skill learning and potentially provided new insights into the therapeutic benefits of motor imagery learning. PMID:24465577

Shaping Early Reorganization of Neural Networks Promotes Motor Function after Stroke

Science.gov (United States)

Volz, L. J.; Rehme, A. K.; Michely, J.; Nettekoven, C.; Eickhoff, S. B.; Fink, G. R.; Grefkes, C.

2016-01-01

Neural plasticity is a major factor driving cortical reorganization after stroke. We here tested whether repetitively enhancing motor cortex plasticity by means of intermittent theta-burst stimulation (iTBS) prior to physiotherapy might promote recovery of function early after stroke. Functional magnetic resonance imaging (fMRI) was used to elucidate underlying neural mechanisms. Twenty-six hospitalized, first-ever stroke patients (time since stroke: 1–16 days) with hand motor deficits were enrolled in a sham-controlled design and pseudo-randomized into 2 groups. iTBS was administered prior to physiotherapy on 5 consecutive days either over ipsilesional primary motor cortex (M1-stimulation group) or parieto-occipital vertex (control-stimulation group). Hand motor function, cortical excitability, and resting-state fMRI were assessed 1 day prior to the first stimulation and 1 day after the last stimulation. Recovery of grip strength was significantly stronger in the M1-stimulation compared to the control-stimulation group. Higher levels of motor network connectivity were associated with better motor outcome. Consistently, control-stimulated patients featured a decrease in intra- and interhemispheric connectivity of the motor network, which was absent in the M1-stimulation group. Hence, adding iTBS to prime physiotherapy in recovering stroke patients seems to interfere with motor network degradation, possibly reflecting alleviation of post-stroke diaschisis. PMID:26980614

Motor sequence learning-induced neural efficiency in functional brain connectivity.

Science.gov (United States)

Karim, Helmet T; Huppert, Theodore J; Erickson, Kirk I; Wollam, Mariegold E; Sparto, Patrick J; Sejdić, Ervin; VanSwearingen, Jessie M

2017-02-15

Previous studies have shown the functional neural circuitry differences before and after an explicitly learned motor sequence task, but have not assessed these changes during the process of motor skill learning. Functional magnetic resonance imaging activity was measured while participants (n=13) were asked to tap their fingers to visually presented sequences in blocks that were either the same sequence repeated (learning block) or random sequences (control block). Motor learning was associated with a decrease in brain activity during learning compared to control. Lower brain activation was noted in the posterior parietal association area and bilateral thalamus during the later periods of learning (not during the control). Compared to the control condition, we found the task-related motor learning was associated with decreased connectivity between the putamen and left inferior frontal gyrus and left middle cingulate brain regions. Motor learning was associated with changes in network activity, spatial extent, and connectivity. Copyright © 2016 Elsevier B.V. All rights reserved.

Functional magnetic resonance imaging of the primary motor cortex

Indian Academy of Sciences (India)

Functional magnetic resonance imaging (fMRI) studies have been performed on 20 right handed volunteers at 1.5 Tesla using echo planar imaging (EPI) protocol. Index finger tapping invoked localized activation in the primary motor area. Consistent and highly reproducible activation in the primary motor area was observed ...

Obesity Reduces Cognitive and Motor Functions across the Lifespan

Science.gov (United States)

Wang, Chuanming; Chan, John S. Y.; Ren, Lijie; Yan, Jin H.

2016-01-01

Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised. PMID:26881095

Obesity Reduces Cognitive and Motor Functions across the Lifespan.

Science.gov (United States)

Wang, Chuanming; Chan, John S Y; Ren, Lijie; Yan, Jin H

2016-01-01

Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised.

Obesity Reduces Cognitive and Motor Functions across the Lifespan

Directory of Open Access Journals (Sweden)

Chuanming Wang

2016-01-01

Full Text Available Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised.

Immediate improvement of motor function after epilepsy surgery in congenital hemiparesis.

Science.gov (United States)

Pascoal, Tharick; Paglioli, Eliseu; Palmini, André; Menezes, Rafael; Staudt, Martin

2013-08-01

Hemispherectomy often leads to a loss of contralateral hand function. In some children with congenital hemiparesis, however, paretic hand function remains unchanged. An immediate improvement of hand function has never been reported. A 17-year-old boy with congenital hemiparesis and therapy-refractory seizures due to a large infarction in the territory of the middle cerebral artery underwent epilepsy surgery. Intraoperatively, electrical cortical stimulation of the affected hemisphere demonstrated preserved motor projections from the sensorimotor cortex to the (contralateral) paretic hand. A frontoparietal resection was performed, which included a complete disconnection of all motor projections originating in the sensorimotor cortex of the affected hemisphere. Surprisingly, the paretic hand showed a significant functional improvement immediately after the operation. This observation demonstrates that, in congenital hemiparesis, crossed motor projections from the affected hemisphere are not always beneficial, but can be dysfunctional, interfering with ipsilateral motor control over the paretic hand by the contralesional hemisphere. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

Decreased function of survival motor neuron protein impairs endocytic pathways.

Science.gov (United States)

Dimitriadi, Maria; Derdowski, Aaron; Kalloo, Geetika; Maginnis, Melissa S; O'Hern, Patrick; Bliska, Bryn; Sorkaç, Altar; Nguyen, Ken C Q; Cook, Steven J; Poulogiannis, George; Atwood, Walter J; Hall, David H; Hart, Anne C

2016-07-26

Spinal muscular atrophy (SMA) is caused by depletion of the ubiquitously expressed survival motor neuron (SMN) protein, with 1 in 40 Caucasians being heterozygous for a disease allele. SMN is critical for the assembly of numerous ribonucleoprotein complexes, yet it is still unclear how reduced SMN levels affect motor neuron function. Here, we examined the impact of SMN depletion in Caenorhabditis elegans and found that decreased function of the SMN ortholog SMN-1 perturbed endocytic pathways at motor neuron synapses and in other tissues. Diminished SMN-1 levels caused defects in C. elegans neuromuscular function, and smn-1 genetic interactions were consistent with an endocytic defect. Changes were observed in synaptic endocytic proteins when SMN-1 levels decreased. At the ultrastructural level, defects were observed in endosomal compartments, including significantly fewer docked synaptic vesicles. Finally, endocytosis-dependent infection by JC polyomavirus (JCPyV) was reduced in human cells with decreased SMN levels. Collectively, these results demonstrate for the first time, to our knowledge, that SMN depletion causes defects in endosomal trafficking that impair synaptic function, even in the absence of motor neuron cell death.

Relationships Between Gross Motor Skills and Social Function in Young Boys With Autism Spectrum Disorder.

Science.gov (United States)

Holloway, Jamie M; Long, Toby M; Biasini, Fred

2018-05-02

The purpose of this study was to examine the relationship between gross motor skills and social function in young boys with autism spectrum disorder. Twenty-one children with autism spectrum disorder participated in the study. The Peabody Developmental Motor Scales Second Edition and the Miller Function and Participation Scales were used to assess gross motor skills. The Social Skills Improvement System Rating Scales was used to assess social function. Moderately high correlations were found between overall gross motor and social skills (r = 0.644) and between the core stability motor subtest and overall social skills (r = -0.672). Specific motor impairments in stability, motor accuracy, and object manipulation scores were predictive of social function. This study suggests that motor skills and social function are related in young boys with autism. Implications for physical therapy intervention are also discussed.

Evaluation of esophageal motor function in clinical practice

NARCIS (Netherlands)

Gyawali, C. P.; Bredenoord, A. J.; Conklin, J. L.; Fox, M.; Pandolfino, J. E.; Peters, J. H.; Roman, S.; Staiano, A.; Vaezi, M. F.

2013-01-01

Esophageal motor function is highly coordinated between central and enteric nervous systems and the esophageal musculature, which consists of proximal skeletal and distal smooth muscle in three functional regions, the upper and lower esophageal sphincters, and the esophageal body. While upper

Comparison of Unmodulated Current Control Characteristics of Permanent Magnet Synchronous Motor

Directory of Open Access Journals (Sweden)

Anwar Muqorobin

2014-12-01

Full Text Available This paper discusses comparison of unmodulated current controls in PMSM, more specifically, on-off, sliding mode, predictive and hybrid controls. The purpose of this study is to select the most appropriate control technique to be adopted. The comparison method is preceded by modeling the motor and entering the values of the motor parameters. PI control is used for speed control and zero d-axis current is employed. Furthermore, performing simulation for each type ofthe selected current controls and analyzing their responses in terms of dq and abc currents, q-axis current response with step reference, as well as THD. Simulation results show that the on-off control gives the best overall performance based on its abc-axis current ripple and THD at large load torque. The hybrid control shows the best response occurring only at the fastest transient time of q-axis current but its response exhibits bad qualities compared with other controls. The predictive control yields the best responses offering the smallest d-axis ripple current and THD at small load torque condition. The sliding mode control, however, does not exhibit any prominent performance compared to the others. Results presented in this paper further indicate that for the PMSM used in the simulation the most appropriate control is the predictive control.

The micro-step motor controller

International Nuclear Information System (INIS)

Hong, Kwang Pyo; Lee, Chang Hee; Moon, Myung Kook; Choi, Bung Hun; Choi, Young Hyun; Cheon, Jong Gu

2004-11-01

The developed micro-step motor controller can handle 4 axes stepping motor drivers simultaneously and provide high power bipolar driving mechanism with constant current mode. It can be easily controlled by manual key functions and the motor driving status is displayed by the front panel VFD. Due to the development of several kinds of communication and driving protocol, PC can operate even several micro-step motor controllers at once by multi-drop connection

Correlations between motor and sensory functions in upper limb chronic hemiparetics after stroke

Directory of Open Access Journals (Sweden)

Thais Botossi Scalha

2011-08-01

Full Text Available OBJECTIVE: Describe the somatosensory function of the affected upper limb of hemiparetic stroke patients and investigate the correlations between measurements of motor and sensory functions in tasks with and without visual deprivation. METHOD: We applied the Fugl-Meyer Assessment (FMA, Nottingham Sensory Assessment (NSA, and several motor and sensory tests: Paper manipulation (PM, Motor Sequences (MS, Reaching and grasping (RG Tests Functional (TF, Tactile Discrimination (TD, Weight Discrimination (WD and Tactile Recognition of Objects (RO. RESULTS: We found moderate correlations between the FMA motor subscale and the tactile sensation score of the NSA. Additionally, the FMA sensitivity was correlated with the NSA total; and performance on the WD test items correlated with the NSA. CONCLUSION: There was a correlation between the sensory and motor functions of the upper limb in chronic hemiparetic stroke patients. Additionally, there was a greater reliance on visual information to compensate for lost sensory-motor skills.

Transcriptomics of aged Drosophila motor neurons reveals a matrix metalloproteinase that impairs motor function.

Science.gov (United States)

Azpurua, Jorge; Mahoney, Rebekah E; Eaton, Benjamin A

2018-04-01

The neuromuscular junction (NMJ) is responsible for transforming nervous system signals into motor behavior and locomotion. In the fruit fly Drosophila melanogaster, an age-dependent decline in motor function occurs, analogous to the decline experienced in mice, humans, and other mammals. The molecular and cellular underpinnings of this decline are still poorly understood. By specifically profiling the transcriptome of Drosophila motor neurons across age using custom microarrays, we found that the expression of the matrix metalloproteinase 1 (dMMP1) gene reproducibly increased in motor neurons in an age-dependent manner. Modulation of physiological aging also altered the rate of dMMP1 expression, validating dMMP1 expression as a bona fide aging biomarker for motor neurons. Temporally controlled overexpression of dMMP1 specifically in motor neurons was sufficient to induce deficits in climbing behavior and cause a decrease in neurotransmitter release at neuromuscular synapses. These deficits were reversible if the dMMP1 expression was shut off again immediately after the onset of motor dysfunction. Additionally, repression of dMMP1 enzymatic activity via overexpression of a tissue inhibitor of metalloproteinases delayed the onset of age-dependent motor dysfunction. MMPs are required for proper tissue architecture during development. Our results support the idea that matrix metalloproteinase 1 is acting as a downstream effector of antagonistic pleiotropy in motor neurons and is necessary for proper development, but deleterious when reactivated at an advanced age. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Current Nondopaminergic Therapeutic Options for Motor Symptoms of Parkinson's Disease

Institute of Scientific and Technical Information of China (English)

Juan-Juan Du; Sheng-Di Chen

2017-01-01

Objective:The aim of this study was to summarize recent studies on nondopaminergic options for the treatment of motor symptoms in Parkinson's disease (PD).Data Sources:Papers in English published in PubMed,Cochrane,and Ovid Nursing databases between January 1988 and November 2016 were searched using the following keywords:PD,nondopaminergic therapy,adenosine,glutamatergic,adrenergic,serotoninergic,histaminic,and iron chelator.We also reviewed the ongoing clinical trials in the website of clinicaltrials.gov.Study Selection:Articles related to the nondopaminergic treatment of motor symptoms in PD were selected for this review.Results:PD is conventionally treated with dopamine replacement strategies,which are effective in the early stages of PD.Long-term use oflevodopa could result in motor complications.Recent studies revealed that nondopaminergic systems such as adenosine,glutamatergic,adrenergic,serotoninergic,histaminic,and iron chelator pathways could include potential therapeutic targets for motor symptoms,including motor fluctuations,levodopa-induced dyskinesia,and gait disorders.Some nondopaminergic drugs,such as istradefylline and amantadine,are currently used clinically,while most such drugs are in preclinical testing stages.Transitioning of these agents into clinically beneficial strategies requires reliable evaluation since several agents have failed to show consistent results despite positive findings at the preclinical level.Conclusions:Targeting nondopaminergic transmission could improve some motor symptoms in PD,especially the discomfort ofdyskinesia.Although nondopaminergic treatments show great potential in PD treatment as an adjunct therapy to levodopa,further investigation is required to ensure their success.

The influence of viscosity on the functioning of molecular motors

NARCIS (Netherlands)

Klok, Martin; Janssen, Leon P.B.M.; Browne, Wesley R.; Feringa, Ben L.

2009-01-01

Light driven molecular motors based on sterically overcrowded alkenes achieve repetitive unidirectional rotation through a sequential series of photochemical and thermal steps. The influence of highly viscous environments on the functioning of unidirectional light driven molecular motors is

Precision electronic speed controller for an alternating-current motor

Science.gov (United States)

Bolie, V.W.

A high precision controller for an alternating-current multi-phase electrical motor that is subject to a large inertial load. The controller was developed for controlling, in a neutron chopper system, a heavy spinning rotor that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal having a meandering line frequency. The controller includes a shaft revolution sensor which provides a feedback pulse train representative of the actual speed of the motor. An internal digital timing signal generator provides a reference signal which is compared with the feedback signal in a computing unit to provide a motor control signal. The motor control signal is a weighted linear sum of a speed error voltage, a phase error voltage, and a drift error voltage, each of which is computed anew with each revolution of the motor shaft. The speed error signal is generated by a novel vernier-logic circuit which is drift-free and highly sensitive to small speed changes. The phase error is also computed by digital logic, with adjustable sensitivity around a 0 mid-scale value. The drift error signal, generated by long-term counting of the phase error, is used to compensate for any slow changes in the average friction drag on the motor. An auxillary drift-byte status sensor prevents any disruptive overflow or underflow of the drift-error counter. An adjustable clocked-delay unit is inserted between the controller and the source of the reference pulse train to permit phase alignment of the rotor to any desired offset angle. The stator windings of the motor are driven by two amplifiers which are provided with input signals having the proper quadrature relationship by an exciter unit consisting of a voltage controlled oscillator, a binary counter, a pair of read-only memories, and a pair of digital-to-analog converters.

Self-regulation of primary motor cortex activity with motor imagery induces functional connectivity modulation: A real-time fMRI neurofeedback study.

Science.gov (United States)

Makary, Meena M; Seulgi, Eun; Kyungmo Park

2017-07-01

Recent developments in data acquisition of functional magnetic resonance imaging (fMRI) have led to rapid preprocessing and analysis of brain activity in a quasireal-time basis, what so called real-time fMRI neurofeedback (rtfMRI-NFB). This information is fed back to subjects allowing them to gain a voluntary control over their own region-specific brain activity. Forty-one healthy participants were randomized into an experimental (NFB) group, who received a feedback directly proportional to their brain activity from the primary motor cortex (M1), and a control (CTRL) group who received a sham feedback. The M1 ROI was functionally localized during motor execution and imagery tasks. A resting-state functional run was performed before and after the neurofeedback training to investigate the default mode network (DMN) modulation after training. The NFB group revealed increased DMN functional connectivity after training to the cortical and subcortical sensory/motor areas (M1/S1 and caudate nucleus, respectively), which may be associated with sensorimotor processing of learning in the resting state. These results show that motor imagery training through rtfMRI-NFB could modulate the DMN functional connectivity to motor-related areas, suggesting that this modulation potentially subserved the establishment of motor learning in the NFB group.

Effects of hippotherapy on gross motor function and functional performance of children with cerebral palsy.

Science.gov (United States)

Park, Eun Sook; Rha, Dong Wook; Shin, Jung Soon; Kim, Soohyeon; Jung, Soojin

2014-11-01

The purpose of our study was to investigate the effects of hippotherapy on gross motor function and functional performance in children with spastic cerebral palsy (CP). We recruited 34 children (M:F=15:19, age: 3-12 years) with spastic CP who underwent hippotherapy for 45 minutes twice a week for 8 weeks. Twenty-one children with spastic CP were recruited for control group. The distribution of gross motor function classification system level and mean age were not significantly different between the two groups. Outcome measures, including the Gross Motor Function Measure (GMFM)-66, GMFM-88 and the Pediatric Evaluation of Disability Inventory: Functional Skills Scale (PEDI-FSS), were assessed before therapy and after the 8-weeks intervention as outcome measures. There were no significant differences between intervention and control groups in mean baseline total scores of GMFM-66, GMFM-88 or PEDI-FSS. After the 8-weeks intervention, mean GMFM-66 and GMFM-88 scores were significantly improved in both groups. However, the hippotherapy group had significantly greater improvement in dimension E and GMFM-66 total score than the control group. The total PEDI-FSS score and the sub-scores of its 3 domains were significantly improved in the hippotherapy group, but not in the control group. The results of our study demonstrate the beneficial effects of hippotherapy on gross motor function and functional performance in children with CP compared to control group. The significant improvement in PEDI-FSS scores suggests that hippotherapy may be useful to maximize the functional performance of children with CP.

Global motion perception is associated with motor function in 2-year-old children.

Science.gov (United States)

Thompson, Benjamin; McKinlay, Christopher J D; Chakraborty, Arijit; Anstice, Nicola S; Jacobs, Robert J; Paudel, Nabin; Yu, Tzu-Ying; Ansell, Judith M; Wouldes, Trecia A; Harding, Jane E

2017-09-29

The dorsal visual processing stream that includes V1, motion sensitive area V5 and the posterior parietal lobe, supports visually guided motor function. Two recent studies have reported associations between global motion perception, a behavioural measure of processing in V5, and motor function in pre-school and school aged children. This indicates a relationship between visual and motor development and also supports the use of global motion perception to assess overall dorsal stream function in studies of human neurodevelopment. We investigated whether associations between vision and motor function were present at 2 years of age, a substantially earlier stage of development. The Bayley III test of Infant and Toddler Development and measures of vision including visual acuity (Cardiff Acuity Cards), stereopsis (Lang stereotest) and global motion perception were attempted in 404 2-year-old children (±4 weeks). Global motion perception (quantified as a motion coherence threshold) was assessed by observing optokinetic nystagmus in response to random dot kinematograms of varying coherence. Linear regression revealed that global motion perception was modestly, but statistically significantly associated with Bayley III composite motor (r 2 =0.06, Pmotor scores (r 2 =0.06, pmotor and fine motor scores, but unaided visual acuity was not statistically significantly associated with any of the motor scores. These results demonstrate that global motion perception and binocular vision are associated with motor function at an early stage of development. Global motion perception can be used as a partial measure of dorsal stream function from early childhood. Copyright © 2017 Elsevier B.V. All rights reserved.

Executive functions as predictors of visual-motor integration in children with intellectual disability.

Science.gov (United States)

Memisevic, Haris; Sinanovic, Osman

2013-12-01

The goal of this study was to assess the relationship between visual-motor integration and executive functions, and in particular, the extent to which executive functions can predict visual-motor integration skills in children with intellectual disability. The sample consisted of 90 children (54 boys, 36 girls; M age = 11.3 yr., SD = 2.7, range 7-15) with intellectual disabilities of various etiologies. The measure of executive functions were 8 subscales of the Behavioral Rating Inventory of Executive Function (BRIEF) consisting of Inhibition, Shifting, Emotional Control, Initiating, Working memory, Planning, Organization of material, and Monitoring. Visual-motor integration was measured with the Acadia test of visual-motor integration (VMI). Regression analysis revealed that BRIEF subscales explained 38% of the variance in VMI scores. Of all the BRIEF subscales, only two were statistically significant predictors of visual-motor integration: Working memory and Monitoring. Possible implications of this finding are further elaborated.

A Smart Current Modulation Scheme for Harmonic Reduction in Three- Phase Motor Drive Applications

DEFF Research Database (Denmark)

Davari, Pooya; Zare, Firuz; Blaabjerg, Frede

2015-01-01

Electric motor-driven systems consume considerable amount of the global electricity. Majority of three-phase motor drives are equipped with conventional diode rectifier and passive harmonic mitigation, being witnessed as the main source in generating input current harmonics. While many active har...

Speed controller for an alternating - current motor

International Nuclear Information System (INIS)

Bolie, V.W.

1984-01-01

A controller for a multi-phase ac motor that is subject to a large inertial load, e.g. an induction motor driving a heavy spinning rotor of a neutron chopper that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal Esub(L) having a meandering line frequency, includes a sensor which provides a feedback pulse train representative of the actual speed of the motor which is compared (by counting clock pulses between feedback pulses) with a reference clock signal in a computing unit to provide a motor control signal Esub(c). The motor control signal is a weighted linear sum of a speed error signal, a phase error signal, and a drift error signal, the magnitudes of which are recalculated and updated with each revolution of the motor shaft. The speed error signal is constant for large speed errors but highly sensitive to small speed errors. The stator windings of the motor are driven by variable-frequency power amplifiers which are controlled by the motor control signal Esub(c) via PROMs which store digital representations of sine and cosine waveforms in quadrature. (author)

Structural and functional evaluation of cortical motor areas in Amyotrophic Lateral Sclerosis.

Science.gov (United States)

Cosottini, Mirco; Pesaresi, Ilaria; Piazza, Selina; Diciotti, Stefano; Cecchi, Paolo; Fabbri, Serena; Carlesi, Cecilia; Mascalchi, Mario; Siciliano, Gabriele

2012-03-01

The structural and functional data gathered with Magnetic Resonance Imaging (MRI) techniques about the brain cortical motor damage in Amyotrophic Lateral Sclerosis (ALS) are controversial. In fact some structural MRI studies showed foci of gray matter (GM) atrophy in the precentral gyrus, even in the early stage, while others did not. Most functional MRI (fMRI) studies in ALS reported hyperactivation of extra-primary motor cortices, while contradictory results were obtained on the activation of the primary motor cortex. We aimed to investigate the cortical motor circuitries in ALS patients by a combined structural and functional approach. Twenty patients with definite ALS and 16 healthy subjects underwent a structural examination with acquisition of a 3D T1-weighted sequence and fMRI examination during a maximal force handgrip task executed with the right-hand, the left-hand and with both hands simultaneously. The T1-weighted images were analyzed with Voxel-Based Morphometry (VBM) that showed several clusters of reduced cortical GM in ALS patients compared to controls including the pre and postcentral gyri, the superior, middle and inferior frontal gyri, the supplementary motor area, the superior and inferior parietal cortices and the temporal lobe, bilaterally but more extensive on the right side. In ALS patients a significant hypoactivation of the primary sensory motor cortex and frontal dorsal premotor areas as compared to controls was observed. The hypoactivated areas matched with foci of cortical atrophy demonstrated by VBM. The fMRI analysis also showed an enhanced activation in the ventral premotor frontal areas and in the parietal cortex pertaining to the fronto-parietal motor circuit which paralleled with disease progression rate and matched with cortical regions of atrophy. The hyperactivation of the fronto-parietal circuit was asymmetric and prevalent in the left hemisphere. VBM and fMRI identified structural and functional markers of an extended

Methylphenidate improves motor functions in children diagnosed with Hyperkinetic Disorder

Directory of Open Access Journals (Sweden)

Iversen Synnøve

2009-05-01

Full Text Available Abstract Background A previous study showed that a high percentage of children diagnosed with Hyperkinetic Disorder (HKD displayed a consistent pattern of motor function problems. The purpose of this study was to investigate the effect of methylphenidate (MPH on such motor performance in children with HKD Methods 25 drug-naïve boys, aged 8–12 yr with a HKD-F90.0 diagnosis, were randomly assigned into two groups within a double blind cross-over design, and tested with a motor assessment instrument, during MPH and placebo conditions. Results The percentage of MFNU scores in the sample indicating 'severe motor problems' ranged from 44–84%, typically over 60%. Highly significant improvements in motor performance were observed with MPH compared to baseline ratings on all the 17 subtests of the MFNU 1–2 hr after administration of MPH. There were no significant placebo effects. The motor improvement was consistent with improvement of clinical symptoms. Conclusion The study confirmed our prior clinical observations showing that children with ADHD typically demonstrate marked improvements of motor functions after a single dose of 10 mg MPH. The most pronounced positive MPH response was seen in subtests measuring either neuromotor inhibition, or heightened muscular tone in the gross movement muscles involved in maintaining the alignment and balance of the body. Introduction of MPH generally led to improved balance and a generally more coordinated and controlled body movement.

Use of the Maximum Torque Sensor to Reduce the Starting Current in the Induction Motor

Directory of Open Access Journals (Sweden)

Muchlas

2010-03-01

Full Text Available Use of the maximum torque sensor has been demonstrated able to improve the standard ramp-up technique in the induction motor circuit system. The induction motor used was of a three-phase squirrel-cage motor controlled using a microcontroller 68HC11. From the simulation done, it has been found that this innovative technique could optimize the performance of motor by introducing low stator current and low power consumption over the standard ramp-up technique.

The count of losses by eddy currents in the windings of electric motors with hollow anchor

Directory of Open Access Journals (Sweden)

N. V. Pribylova

2017-01-01

Full Text Available Given the rationale of taking into account losses on eddy currents in the windings of a low-inertia DC motors with offered magnetoelectric systems. Increased in recent years, the power of these motors (through the use of highly coercive magnets permanent caused an increase in the volume of copper in the air gap and the magnetic induction values. All this has values given rise to significant eddy currents in the windings made in the air gap, and hence the necessity of taking into account losses from these currents. The experimentally obtained dependence of the losses on eddy currents on the frequency of rotation for a DC motor with a hollow anchor with a power of 350 watts. The magnitude of these losses can reach 30% of the nominal power of the motor. Described mechanism of occurrence of losses. Eddy currents occur in areas with variable magnetic flux and cause the appearance of force, which is directed toward the velocity vector and inhibits the anchor. The directions of these currents, the vectors of magnetic induction, magnetic field and force acting on the conductor winding and a braking anchor. The proposed methods reduce losses: crushing contours of eddy currents and achieve uniform distribution of magnetic induction in the interpolar space of the motor. Shows their strengths and weaknesses. The crushing circuits of windings occur surge currents. To eliminate the losses on the surge currents it is necessary to apply a transposition of the conductors. Given a refined formula for finding the losses on eddy currents in the armature winding, the conductors of which is made in the form of a harness of several wires. Formula has shown a good convergence with experimental data.

Enhanced Motor Skill Acquisition in the Non-dominant Upper Extremity using Intermittent Theta Burst Stimulation and Transcranial Direct Current Stimulation

Directory of Open Access Journals (Sweden)

Ray eButts

2014-06-01

Full Text Available Individuals suffering from motor impairments often require physical therapy (PT to help improve their level of function. Previous investigations suggest that both intermittent theta burst stimulation (iTBS and bihemispheric transcranial direct current stimulation may increase the speed and extent of motor learning/relearning and that this increase may be related to brain derived neurotrophic factor (BDNF. The purpose of the current study was to explore the feasibility and effectiveness of a novel, non-invasive brain stimulation approach that combined an iTBS primer, and bihemispheric stimulation coupled with motor training. We hypothesized that individuals exposed to this novel treatment would make greater functional improvements than individuals undergoing sham stimulation when tested immediately following, 24-hours, and 7-days post-training. A total of 26 right-handed, healthy young adults were randomly assigned to either a treatment (n = 15 or control group (n = 12. iTBS (20 trains of 10 pulse triplets each delivered at 80% AMT / 50Hz over 191.84 seconds and bihemispheric tDCS (1.0 ma for 20 minutes were used as a primer to, and in conjunction with, 20 minutes of motor training, respectively. Our primary outcome measure was performance on the Jebsen-Taylor Hand Function Test. Participants tolerated the combined iTBS/bihemispheric stimulation treatment without complaint. While performance gains in the sham and stimulation group were not significant immediately after training, they were nearly significant 24-hours post training (p = 0.055, and were significant at 7-days post training (p < 0.05. These results suggest that the combined iTBS/bihemispheric stimulation protocol is both feasible and effective. Future research should examine the mechanistic explanation of this approach as well as the potential of using this approach in clinical populations.

Alcohol hangover: type and time-extension of motor function impairments.

Science.gov (United States)

Karadayian, Analía G; Cutrera, Rodolfo A

2013-06-15

Alcohol hangover is defined as the unpleasant next-day state following an evening of excessive alcohol consumption. Hangover begins when ethanol is absent in plasma and is characterized by physical and psychological symptoms. During hangover cognitive functions and subjective capacities are affected along with inefficiency, reduced productivity, absenteeism, driving impairments, poor academic achievement and reductions in motor coordination. The aim of this work was to study the type and length of motor and exploratory functions from the beginning to the end of the alcohol hangover. Male Swiss mice were injected i.p. either with saline (control group) or with ethanol (3.8 g/kg BW) (hangover group). Motor performance, walking deficiency, motor strength, locomotion and exploratory activity were evaluated at a basal point (ZT0) and every 2 h up to 20 h after blood alcohol levels were close to zero (hangover onset). Motor performance was 80% decreased at the onset of hangover (pwalking deficiencies from the beginning to 16 h after hangover onset (popen field test and the exploratory activity on T-maze and hole board tests were reduced during 16 h after hangover onset (ptime-extension between 16 to 20 h for hangover motor and exploratory impairments. As a whole, this study shows the long lasting effects of alcohol hangover. Copyright © 2013 Elsevier B.V. All rights reserved.

Progressive motor cortex functional reorganization following 6-hydroxydopamine lesioning in rats.

Science.gov (United States)

Viaro, Riccardo; Morari, Michele; Franchi, Gianfranco

2011-03-23

Many studies have attempted to correlate changes of motor cortex activity with progression of Parkinson's disease, although results have been controversial. In the present study we used intracortical microstimulation (ICMS) combined with behavioral testing in 6-hydroxydopamine hemilesioned rats to evaluate the impact of dopamine depletion on movement representations in primary motor cortex (M1) and motor behavior. ICMS allows for motor-effective stimulation of corticofugal neurons in motor areas so as to obtain topographic movements representations based on movement type, area size, and threshold currents. Rats received unilateral 6-hydroxydopamine in the nigrostriatal bundle, causing motor impairment. Changes in M1 were time dependent and bilateral, although stronger in the lesioned than the intact hemisphere. Representation size and threshold current were maximally impaired at 15 d, although inhibition was still detectable at 60-120 d after lesion. Proximal forelimb movements emerged at the expense of the distal ones. Movement lateralization was lost mainly at 30 d after lesion. Systemic L-3,4-dihydroxyphenylalanine partially attenuated motor impairment and cortical changes, particularly in the caudal forelimb area, and completely rescued distal forelimb movements. Local application of the GABA(A) antagonist bicuculline partially restored cortical changes, particularly in the rostral forelimb area. The local anesthetic lidocaine injected into the M1 of the intact hemisphere restored movement lateralization in the lesioned hemisphere. This study provides evidence for motor cortex remodeling after unilateral dopamine denervation, suggesting that cortical changes were associated with dopamine denervation, pathogenic intracortical GABA inhibition, and altered interhemispheric activity.

Motor function and respiratory capacity in patients with late-onset pompe disease

DEFF Research Database (Denmark)

Illes, Zsolt; Mike, Andrea; Trauninger, Anita

2014-01-01

Introduction: The relationship between skeletal muscle strength and respiratory dysfunction in Pompe disease has not been examined by quantitative methods. We investigated correlations among lower extremity proximal muscle strength, respiratory function, and motor performance. Methods: Concentric...... strength of the knee extensor and flexor muscles were measured with a dynamometer, and pulmonary function was evaluated using spirometry in 7 adult patients. The six-minute walk test and the four-step stair-climb test were used for assessing aerobic endurance and anaerobic power, respectively. Results......: Anaerobic motor performance correlated with strength of both thigh muscles. Respiratory function did not correlate with either muscle strength or motor function performance. Conclusions: Respiratory and lower extremity proximal muscles could be differentially affected by the disease in individual patients...

Effects of occupational therapy services on fine motor and functional performance in preschool children.

Science.gov (United States)

Case-Smith, J

2000-01-01

This study examined how performance components and variables in intervention influenced fine motor and functional outcomes in preschool children. In a sample of 44 preschool-aged children with fine motor delays who received occupational therapy services, eight fine motor and functional performance assessments were administered at the beginning and end of the academic year. Data on the format and intervention activities of each occupational therapy session were recorded for 8 months. The children received a mean of 23 sessions, in both individual and group format. Most of the sessions (81%) used fine motor activities; 29% addressed peer interaction, and 16% addressed play skills. Visual motor outcomes were influenced by the number of intervention sessions and percent of sessions with play goals. Fine motor outcomes were most influenced by the therapists' emphasis on play and peer interaction goals; functional outcomes were influenced by number of sessions and percent of sessions that specifically addressed self-care goals. The influence of play on therapy outcomes suggests that a focus on play in intervention activities can enhance fine motor and visual motor performance.

Myoelectric hand prosthesis force control through servo motor current feedback.

Science.gov (United States)

Sono, Tálita Saemi Payossim; Menegaldo, Luciano Luporini

2009-10-01

This paper presents the prehension force closed-loop control design of a mechanical finger commanded by electromyographic signal (EMG) from a patient's arm. The control scheme was implemented and tested in a mechanical finger prototype with three degrees of freedom and one actuator, driven by arm muscles EMG of normal volunteers. Real-time indirect estimation of prehension force was assessed by measuring the DC servo motor actuator current. A model of the plant comprising finger, motor, and grasped object was proposed. Model parameters were identified experimentally and a classical feedback phase-lead compensator was designed. The controlled mechanical finger was able to provide a more accurate prehension force modulation of a compliant object when compared to open-loop control.

Association between fine motor skills and binocular visual function in children with reading difficulties.

Science.gov (United States)

Niechwiej-Szwedo, Ewa; Alramis, Fatimah; Christian, Lisa W

2017-12-01

Performance of fine motor skills (FMS) assessed by a clinical test battery has been associated with reading achievement in school-age children. However, the nature of this association remains to be established. The aim of this study was to assess FMS in children with reading difficulties using two experimental tasks, and to determine if performance is associated with reduced binocular function. We hypothesized that in comparison to an age- and sex-matched control group, children identified with reading difficulties will perform worse only on a motor task that has been shown to rely on binocular input. To test this hypothesis, motor performance was assessed using two tasks: bead-threading and peg-board in 19 children who were reading below expected grade and age-level. Binocular vision assessment included tests for stereoacuity, fusional vergence, amplitude of accommodation, and accommodative facility. In comparison to the control group, children with reading difficulties performed significantly worse on the bead-threading task. In contrast, performance on the peg-board task was similar in both groups. Accommodative facility was the only measure of binocular function significantly associated with motor performance. Findings from our exploratory study suggest that normal binocular vision may provide an important sensory input for the optimal development of FMS and reading. Given the small sample size tested in the current study, further investigation to assess the contribution of binocular vision to the development and performance of FMS and reading is warranted. Copyright © 2017 Elsevier B.V. All rights reserved.

Functional significance of ipsilesional motor deficits after unilateral stroke.

Science.gov (United States)

Chestnut, Caitilin; Haaland, Kathleen Y

2008-01-01

To determine whether ipsilesional motor skills, which have been related to independent functioning, are present chronically after unilateral stroke and are more common in people with apraxia than in those without apraxia. Observational cohort comparing the performance of an able-bodied control group, stroke patients with left- or right-hemisphere damage matched for lesion volume, and left-hemisphere stroke patients with and without ideomotor limb apraxia. Primary care Veterans Affairs and private medical center. Volunteer right-handed sample; stroke patients with left- or right-hemisphere damage about 4 years poststroke; a control group of demographically matched, able-bodied adults. Not applicable. Total time to perform the (1) Williams doors test and the (2) timed manual performance test (TMPT), which includes parts of the Jebsen-Taylor Hand Function Test. Ipsilesional motor deficits were present after left- or right-hemisphere stroke when using both measures, but deficits were consistently more common in patients with limb apraxia only for the TMPT. These findings add to a growing literature that suggests that ipsilesional motor deficits may have a functional impact in unilateral stroke patients, especially in patients with ideomotor limb apraxia.

Music-supported therapy (MST) in improving post-stroke patients' upper-limb motor function: a randomised controlled pilot study.

Science.gov (United States)

Tong, Yanna; Forreider, Brian; Sun, Xinting; Geng, Xiaokun; Zhang, Weidong; Du, Huishan; Zhang, Tong; Ding, Yuchuan

2015-05-01

Music-supported therapy (MST) is a new approach for motor rehabilitation of stroke patients. Recently, many studies have demonstrated that MST improved the motor functions of post-stroke patients. However, the underlying mechanism for this effect is still unclear. It may result from repeated practice or repeated practice combined with musical stimulation. Currently, few studies have been designed to clarify this discrepancy. In this study, the application of "mute" musical instruments allowed for the study of music as an independent factor. Thirty-three post-stroke patients with no substantial previous musical training were included. Participants were assigned to either audible music group (MG) or mute music group (CG), permitting observation of music's independent effect. All subjects received the conventional rehabilitation treatments. Patients in MG (n = 15) received 20 extra sessions of audible musical instrument training over 4 weeks. Patients in CG (n = 18) received "mute" musical instrument training of the same protocol as that of MG. Wolf motor function test (WMFT) and Fugl-Meyer assessment (FMA) for upper limbs were utilised to evaluate motor functions of patients in both groups before and after the treatment. Three patients in CG dropped out. All participants in both groups showed significant improvements in motor functions of upper limbs after 4  weeks' treatment. However, significant differences in the WMFT were found between the two groups (WMFT-quality: P = 0.025; WMFT-time: P = 0.037), but not in the FMA (P = 0.448). In short, all participants showed significant improvement after 4 weeks' treatment, but subjects in MG demonstrated greater improvement than those in CG. This study supports that MST, when combined with conventional treatment, is effective for the recovery of motor skills in post-stroke patients. Additionally, it suggests that apart from the repetitive practices of MST, music may play a unique role in improving

Ocular Motor Score (OMS): a clinical tool to evaluating ocular motor functions in children. Intrarater and inter-rater agreement.

Science.gov (United States)

Olsson, Monica; Teär Fahnehjelm, Kristina; Rydberg, Agneta; Ygge, Jan

2015-08-01

Ocular motor score (OMS) is a new clinical test protocol for evaluating ocular motor functions in children and young adults. OMS is a set of 15 important and relevant non-invasive ocular motor function parameters derived from clinical practice. The aim of the study was to evaluate OMS according to intrarater and inter-rater agreement. Forty children aged 4-10 years, 23 girls median age 6.5 (range 4.3-9.3) and 17 boys median age 5.8 (range 4.1-9.8) were included. The ocular motor functions were assessed and scored according to the OMS protocol. The examinations were videotaped. To obtain the intrarater agreement, the first author examined and scored the children twice, first in the clinic and 2 weeks later by watching the videotape. To obtain the inter-rater agreement, three other raters independently scored the ocular motor function of the children by watching the videotapes. The overall observed intrarater agreement was 88%, and the observed inter-rater agreement between the three raters was 80%. For none of the subtests was there an observed intrarater agreement lower than 65%. Three of the subtests had an observed inter-rater agreement of 65% or below. Overall there was high observed intra- and inter-rater agreement for the OMS test protocol. Subtests such as saccades and smooth pursuit were more difficult for raters to score similarly according the clinical OMS test protocol. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Gastrointestinal motor function in patients with portal hypertension

DEFF Research Database (Denmark)

Madsen, Jan Lysgård; Brinch, K; Hansen, Erik Feldager

2000-01-01

BACKGROUND: Existing data on gastric emptying and small-intestinal transit rates in portal-hypertensive patients are scarce and contradictory, and so far, the motor function of the colon has not been assessed in these patients. In this study we evaluated the propulsive effect of all main segments...... of the gastrointestinal tract in patients with well-characterized portal hypertension. METHODS: Eight patients with a postsinusoidal hepatic pressure gradient of at least 13 mmHg and eight age- and sex-matched healthy controls participated in the study. Gastric emptying, small-intestinal transit, and colonic transit...... the test meal between patients and controls. CONCLUSIONS: These data suggest that the colonic transit is often accelerated in patients with portal hypertension, whereas the motor function of the stomach and the small intestine is unaffected....

A review of monopolar motor mapping and a comprehensive guide to continuous dynamic motor mapping for resection of motor eloquent brain tumors.

Science.gov (United States)

Schucht, P; Seidel, K; Jilch, A; Beck, J; Raabe, A

2017-06-01

Monopolar mapping of motor function differs from the most commonly used method of intraoperative mapping, i.e. bipolar direct electrical stimulation at 50-60Hz (Penfield technique mapping). Most importantly, the monopolar probe emits a radial, homogenous electrical field different to the more focused inter-tip bipolar electrical field. Most users combine monopolar stimulation with the short train technique, also called high frequency stimulation, or train-of-five techniques. It consists of trains of four to nine monopolar rectangular electrical pulses of 200-500μs pulse length with an inter stimulus interval of 2-4msec. High frequency short train stimulation triggers a time-locked motor-evoked potential response, which has a defined latency and an easily quantifiable amplitude. In this way, motor thresholds might be used to evaluate a current-to-distance relation. The homogeneous electrical field and the current-to-distance approximation provide the surgeon with an estimate of the remaining distance to the corticospinal tract, enabling the surgeon to adjust the speed of resection as the corticospinal tract is approached. Furthermore, this stimulation paradigm is associated with a lower incidence of intraoperative seizures, allowing continuous stimulation. Hence, monopolar mapping is increasingly used as part of a strategy of continuous dynamic mapping: ergonomically integrated into the surgeon's tools, the monopolar probe reliably provides continuous/uninterrupted feedback on motor function. As part of this strategy, motor mapping is not any longer a time consuming interruption of resection but rather a radar-like, real-time information system on the spatial relationship of the current resection site to eloquent motor structures. Copyright © 2017. Published by Elsevier Masson SAS.

IGF-1 delivery to CNS attenuates motor neuron cell death but does not improve motor function in type III SMA mice.

Science.gov (United States)

Tsai, Li-Kai; Chen, Yi-Chun; Cheng, Wei-Cheng; Ting, Chen-Hung; Dodge, James C; Hwu, Wuh-Liang; Cheng, Seng H; Passini, Marco A

2012-01-01

The efficacy of administering a recombinant adeno-associated virus (AAV) vector encoding human IGF-1 (AAV2/1-hIGF-1) into the deep cerebellar nucleus (DCN) of a type III SMA mouse model was evaluated. High levels of IGF-1 transcripts and protein were detected in the spinal cord at 2 months post-injection demonstrating that axonal connections between the cerebellum and spinal cord were able to act as conduits for the viral vector and protein to the spinal cord. Mice treated with AAV2/1-hIGF-1 and analyzed 8 months later showed changes in endogenous Bax and Bcl-xl levels in spinal cord motor neurons that were consistent with IGF-1-mediated anti-apoptotic effects on motor neurons. However, although AAV2/1-hIGF-1 treatment reduced the extent of motor neuron cell death, the majority of rescued motor neurons were non-functional, as they lacked axons that innervated the muscles. Furthermore, treated SMA mice exhibited abnormal muscle fibers, aberrant neuromuscular junction structure, and impaired performance on motor function tests. These data indicate that although CNS-directed expression of IGF-1 could reduce motor neuron cell death, this did not translate to improvements in motor function in an adult mouse model of type III SMA. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of blueberries on inflammation, motor performance and cognitive function

Science.gov (United States)

Motor and cognitive function decrease with age, to include deficits in balance, coordination, gait, processing speed, executive function, memory, and spatial learning. These functional declines may be caused by long term increases in and susceptibility to oxidative stress and inflammation. Research ...

Design of motors for inverter operation

Energy Technology Data Exchange (ETDEWEB)

Haring, T. [ABB Motors OY, Vaasa (Finland)

2000-07-01

This paper describes very practical principles of how an induction motor should be designed for converter application. The main focus targets the efficiency of the motor and drive. The results presented are based on actual test motors and FEM-calculation simulations. FEM-calculation together with a time-stepping function is a powerful tool for estimating magnetic flux densities, iron losses, current densities and corresponding losses in windings, in other words a tool for optimisation of the motor design. Time-stepping is rather time consuming because all the circuit equations must be solved for each time-step, but it provides a way to estimate the iron losses; hysteresis and eddy current losses as well as current distribution and current losses. The calculation tool also provides the possibility to check if an existing motor is feasible for a converter drive. Alternatively if a motor is only to be supplied by a converter there are many more degrees of freedom in the electrical design and the motor may be optimised for that converter drive by incorporationg rather simple design changes. Additionally a design compromise, ''a general purpose motor'' useable for DOL and feasible for converter drive can be produced following the principles presented herewith. The converter types which are considered are indirect types and mainly voltage source converters since they are the most common on the market and are ''general purpose converters'' and providing a certain freedom to select the motor for the drive. Current source converters require ''matching'' with the motor and therefore need a precise knowledge of the motor equivalent circuit, making the selection of the motor more complicated. (orig.)

Gross and fine motor function in fibromyalgia and chronic fatigue syndrome.

Science.gov (United States)

Rasouli, Omid; Fors, Egil A; Borchgrevink, Petter Chr; Öhberg, Fredrik; Stensdotter, Ann-Katrin

2017-01-01

This paper aimed to investigate motor proficiency in fine and gross motor function, with a focus on reaction time (RT) and movement skill, in patients with fibromyalgia (FM) and chronic fatigue syndrome (CFS) compared to healthy controls (HC). A total of 60 individuals (20 CFS, 20 FM, and 20 HC), age 19-49 years, participated in this study. Gross motor function in the lower extremity was assessed using a RT task during gait initiation in response to an auditory trigger. Fine motor function in the upper extremity was measured during a precision task (the Purdue Pegboard test) where the number of pins inserted within 30 s was counted. No significant differences were found between FM and CFS in any parameters. FM and CFS groups had significantly longer RT than HC in the gait initiation ( p =0.001, and p =0.004 respectively). In the Purdue Pegboard test, 20% in the FM group, 15% in the CFS groups, and 0% of HC group, scored below the threshold of the accepted performance. However, there were no significant differences between FM, CFS, and HC in this task ( p =0.12). Compared to controls, both CFS and FM groups displayed significantly longer RT in the gait initiation task. Generally, FM patients showed the worst results in both tests, although no group differences were found in fine motor control, according to the Purdue Pegboard test.

Action in Perception: Prominent Visuo-Motor Functional Symmetry in Musicians during Music Listening.

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Iballa Burunat

Full Text Available Musical training leads to sensory and motor neuroplastic changes in the human brain. Motivated by findings on enlarged corpus callosum in musicians and asymmetric somatomotor representation in string players, we investigated the relationship between musical training, callosal anatomy, and interhemispheric functional symmetry during music listening. Functional symmetry was increased in musicians compared to nonmusicians, and in keyboardists compared to string players. This increased functional symmetry was prominent in visual and motor brain networks. Callosal size did not significantly differ between groups except for the posterior callosum in musicians compared to nonmusicians. We conclude that the distinctive postural and kinematic symmetry in instrument playing cross-modally shapes information processing in sensory-motor cortical areas during music listening. This cross-modal plasticity suggests that motor training affects music perception.

Effects of transcranial direct current stimulation on motor learning in healthy individuals: a systematic review

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Águida Foerster

Full Text Available Introduction Transcranial direct current stimulation (tDCS has been used to modify cortical excitability and promote motor learning. Objective To systematically review published data to investigate the effects of transcranial direct current stimulation on motor learning in healthy individuals. Methods Randomized or quasi-randomized studies that evaluated the tDCS effects on motor learning were included and the risk of bias was examined by Cochrane Collaboration’s tool. The following electronic databases were used: PubMed, Scopus, Web of Science, LILACS, CINAHL with no language restriction. Results It was found 160 studies; after reading the title and abstract, 17 of those were selected, but just 4 were included. All studies involved healthy, right-handed adults. All studies assessed motor learning by the Jebsen Taylor Test or by the Serial Finger Tapping Task (SFTT. Almost all studies were randomized and all were blinding for participants. Some studies presented differences at SFTT protocol. Conclusion The result is insufficient to draw conclusions if tDCS influences the motor learning. Furthermore, there was significant heterogeneity of the stimulation parameters used. Further researches are needed to investigate the parameters that are more important for motor learning improvement and measure whether the effects are long-lasting or limited in time.

Improving Survival and Promoting Respiratory Motor Function After Cervical Spinal Cord Injury

Science.gov (United States)

2017-09-01

AWARD NUMBER: W81XWH-15-1-0378 TITLE: Improving Survival and Promoting Respiratory Motor Function After Cervical Spinal Cord Injury PRINCIPAL...TITLE AND SUBTITLE CordCorInjury 5a. CONTRACT NUMBER Improvi g Survival and Promoting Respiratory Motor Function After Cervical Spinal Cord...care. However, despite these drastic interventions, the cervical injured patient is still susceptible to death due to respiratory complications

Roentgenological characteristics of motor-evacuatory stomach function after selective proximal vagotomy (SPV)

International Nuclear Information System (INIS)

Rustamov, Eh.A.; Manafov, S.S.

1988-01-01

An x-ray picture of motor-evacuatory stomach function was studied in patients with pyloroduodenal ulcers after SPV with and without drainage (435 patients aged 16 to 80). Methods of investigation included polyprojectional radioscopy and panoramic and spot films at various time intervals after barium suspension intake. Stomach investigation was performed before operation as well as 2-3 weeks, 3-6 mos, 1-2 yrs, 3-5 yrs, and 7-10 yrs after it. Motor-evacuatory stomach function was studied over time. The least changes in motor-evacuatory fucntion were observed after SPV without drainage as a result of preserving pyloric contractility

ELECTRIC MOTOR DIAGNOSTICS OF SWITCHES BASED ON THE NEURAL NETWORK DATA MODELING THE SPECTRAL DECOMPOSITION OF THE CURRENTS

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O. M. Shvets

2009-07-01

Full Text Available The method of automated diagnostics of electric motors is offered. It uses a neural network revealing the electric motor faults on the basis of analysis of frequency spectrum of current flowing through the motor.

ALS-associated mutant FUS induces selective motor neuron degeneration through toxic gain of function.

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Sharma, Aarti; Lyashchenko, Alexander K; Lu, Lei; Nasrabady, Sara Ebrahimi; Elmaleh, Margot; Mendelsohn, Monica; Nemes, Adriana; Tapia, Juan Carlos; Mentis, George Z; Shneider, Neil A

2016-02-04

Mutations in FUS cause amyotrophic lateral sclerosis (ALS), including some of the most aggressive, juvenile-onset forms of the disease. FUS loss-of-function and toxic gain-of-function mechanisms have been proposed to explain how mutant FUS leads to motor neuron degeneration, but neither has been firmly established in the pathogenesis of ALS. Here we characterize a series of transgenic FUS mouse lines that manifest progressive, mutant-dependent motor neuron degeneration preceded by early, structural and functional abnormalities at the neuromuscular junction. A novel, conditional FUS knockout mutant reveals that postnatal elimination of FUS has no effect on motor neuron survival or function. Moreover, endogenous FUS does not contribute to the onset of the ALS phenotype induced by mutant FUS. These findings demonstrate that FUS-dependent motor degeneration is not due to loss of FUS function, but to the gain of toxic properties conferred by ALS mutations.

Impacts of Sensation, Perception, and Motor Abilities of the Ipsilesional Upper Limb on Hand Functions in Unilateral Stroke: Quantifications From Biomechanical and Functional Perspectives.

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Hsu, Hsiu-Yun; Ke, Chia-Wen; Kuan, Ta-Shen; Yang, Hsiu-Ching; Tsai, Ching-Liang; Kuo, Li-Chieh

2018-02-01

The presence of subtle losses in hand dexterity after stroke affects the regaining of independence with regard to activities of daily living. Therefore, awareness of ipsilesional upper extremity (UE) function may be of importance when developing a comprehensive rehabilitation program. However, current hand function tests seem to be unable to identify asymptomatic UE impairments. To assess the motor coordination as well as the sensory perception of an ipsilesional UE using biomechanical analysis of performance-oriented tasks and conducting a Manual Tactile Test (MTT). Case-controlled study. A university hospital. A total of 21 patients with unilateral stroke, along with 21 matched healthy control subjects, were recruited. Each participant was requested to perform a pinch-holding-up activity (PHUA) test, object-transport task, and reach-to-grasp task via motion capture, as well as the MTT. The kinetic data of the PHUA test, kinematics analysis of functional movements, and time requirement of MTT were analyzed. Patients with ipsilesional UE had an inferior ability to scale and produce pinch force precisely when conducting the PHUA test compared to the healthy controls (P perception (P sensation-perception-motor system in the ipsilesional UE. Integration of sensorimotor training programs for ipsilesional UE in future neuro-rehabilitation strategies may provide more beneficial effects to regain patients' motor recovery and to promote daily living activity independence than focusing on paretic arm motor training alone. III. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

submitter Estimation of stepping motor current from long distances through cable-length-adaptive piecewise affine virtual sensor

CERN Document Server

Oliveri, Alberto; Masi, Alessandro; Storace, Marco

2015-01-01

In this paper a piecewise affine virtual sensor is used for the estimation of the motor-side current of hybrid stepper motors, which actuate the LHC (Large Hadron Collider) collimators at CERN. The estimation is performed starting from measurements of the current in the driver, which is connected to the motor by a long cable (up to 720 m). The measured current is therefore affected by noise and ringing phenomena. The proposed method does not require a model of the cable, since it is only based on measured data and can be used with cables of different length. A circuit architecture suitable for FPGA implementation has been designed and the effects of fixed point representation of data are analyzed.

Axonal regeneration and neuronal function are preserved in motor neurons lacking ß-actin in vivo.

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Thomas R Cheever

2011-03-01

Full Text Available The proper localization of ß-actin mRNA and protein is essential for growth cone guidance and axon elongation in cultured neurons. In addition, decreased levels of ß-actin mRNA and protein have been identified in the growth cones of motor neurons cultured from a mouse model of Spinal Muscular Atrophy (SMA, suggesting that ß-actin loss-of-function at growth cones or pre-synaptic nerve terminals could contribute to the pathogenesis of this disease. However, the role of ß-actin in motor neurons in vivo and its potential relevance to disease has yet to be examined. We therefore generated motor neuron specific ß-actin knock-out mice (Actb-MNsKO to investigate the function of ß-actin in motor neurons in vivo. Surprisingly, ß-actin was not required for motor neuron viability or neuromuscular junction maintenance. Skeletal muscle from Actb-MNsKO mice showed no histological indication of denervation and did not significantly differ from controls in several measurements of physiologic function. Finally, motor axon regeneration was unimpaired in Actb-MNsKO mice, suggesting that ß-actin is not required for motor neuron function or regeneration in vivo.

Human Motor Cortex Functional Changes in Acute Stroke: Gender Effects

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Vincenzo eDi Lazzaro

2016-01-01

Full Text Available The acute phase of stroke is accompanied by functional changes in the activity and interplay of both hemispheres. In healthy subjects, gender is known to impact the functional brain organization.We investigated whether gender influences also acute stroke functional changes. In thirty-five ischemic stroke patients, we evaluated the excitability of the affected (AH and unaffected hemisphere (UH by measuring resting and active motor threshold and motor-evoked potential amplitude under baseline conditions and after intermittent theta burst stimulation (iTBS of AH. We also computed an index of the excitability balance between the hemispheres, laterality indexes (LI, to evidence hemispheric asymmetry. Active motor threshold differed significantly between AH and UH only in the male group (p=0.004, not in females (p>0.200, and both LIAMT and LIRMT were significantly higher in males than in females (respectively p=0.033 and p=0.042. LTP-like activity induced by iTBS in AH was more frequent in females. Gender influences the functional excitability changes that take place after human stroke and the level of LTP that can be induced by repetitive stimulation. This knowledge is of high value in the attempt of individualizing to different genders any non-invasive stimulation strategy designed to foster stroke recovery.

Effect of Obesity on Motor Functional Outcome of Rehabilitating Traumatic Brain Injury Patients.

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Le, David; Shafi, Shahid; Gwirtz, Patricia; Bennett, Monica; Reeves, Rustin; Callender, Librada; Dunklin, Cynthia; Cleveland, Samantha

2015-08-01

The aim of this study was to determine the association between obesity and functional motor outcome of patients undergoing inpatient rehabilitation after traumatic brain injury. This retrospective study at an urban acute inpatient rehabilitation center screened data from 761 subjects in the Traumatic Brain Injury Model System who were admitted from January 2010 to September 2013. Inclusion criteria consisted of age of 18 years or older and an abnormal Functional Independence Measure motor score. Body mass index was used to determine obesity in the study population. Patients with a body mass index of 30.0 kg/m or greater were considered obese. A total of 372 subjects met the criteria for inclusion in the study. Of these, 54 (13.2%) were obese. Both obese and nonobese patients showed similar improvement in Functional Independence Measure motor score (mean [SD], 30.4 [12.8] for the obese patients, P = 0.115, and 27.3 [13.1] for the nonobese patients). The mean (SD) Functional Independence Measure motor scores at discharge for the obese and nonobese patients were 63.0 (12.6) and 62.3 (10.1) (P = 0.6548), respectively. Obesity had no adverse impact on motor functional outcomes of the traumatic brain injury patients who underwent inpatient rehabilitation. Therefore, obesity should not be considered an obstacle in inpatient rehabilitation after traumatic brain injury, if patients are able to participate in necessary therapy.

Towards an ankle neuroprosthesis for hybrid robotics: Concepts and current sources for functional electrical stimulation.

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Casco, S; Fuster, I; Galeano, R; Moreno, J C; Pons, J L; Brunetti, F

2017-07-01

Hybrid rehabilitation robotics combine neuro-prosthetic devices (close-loop functional electrical stimulation systems) and traditional robotic structures and actuators to explore better therapies and promote a more efficient motor function recovery or compensation. Although hybrid robotics and ankle neuroprostheses (NPs) have been widely developed over the last years, there are just few studies on the use of NPs to electrically control both ankle flexion and extension to promote ankle recovery and improved gait patterns in paretic limbs. The aim of this work is to develop an ankle NP specifically designed to work in the field of hybrid robotics. This article presents early steps towards this goal and makes a brief review about motor NPs and Functional Electrical Stimulation (FES) principles and most common devices used to aid the ankle functioning during the gait cycle. It also shows a current sources analysis done in this framework, in order to choose the best one for this intended application.

Functional MRI in human motor control studies and clinical applications

International Nuclear Information System (INIS)

Toma, Keiichiro

2002-01-01

Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

Functional MRI in human motor control studies and clinical applications

Energy Technology Data Exchange (ETDEWEB)

Toma, Keiichiro [Kyoto Univ. (Japan). Graduate School of Medicine; Nakai, Toshiharu [Inst. of Biomedical Research and Innovation, Kobe (Japan)

2002-07-01

Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

Brain implants for substituting lost motor function: state of the art and potential impact on the lives of motor-impaired seniors.

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Ramsey, N F; Aarnoutse, E J; Vansteensel, M J

2014-01-01

Recent scientific achievements bring the concept of neural prosthetics for reinstating lost motor function closer to medical application. Current research involves severely paralyzed people under the age of 65, but implications for seniors with stroke or trauma-induced impairments are clearly on the horizon. Demographic changes will lead to a shortage of personnel to care for an increasing population of senior citizens, threatening maintenance of an acceptable level of care and urging ways for people to live longer at their home independent from personal assistance. This is particularly challenging when people suffer from disabilities such as partial paralysis after stroke or trauma, where daily personal assistance is required. For some of these people, neural prosthetics can reinstate some lost motor function and/or lost communication, thereby increasing independence and possibly quality of life. In this viewpoint article, we present the state of the art in decoding brain activity in the service of brain-computer interfacing. Although some noninvasive applications produce good results, we focus on brain implants that benefit from better quality brain signals. Fully implantable neural prostheses for home use are not available yet, but clinical trials are being prepared. More sophisticated systems are expected to follow in the years to come, with capabilities of interest for less severe paralysis. Eventually the combination of smart robotics and brain implants is expected to enable people to interact well enough with their environment to live an independent life in spite of motor disabilities. © 2014 S. Karger AG, Basel.

Early functional impairment of sensory-motor connectivity in a mouse model of spinal muscular atrophy

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Mentis, George Z.; Blivis, Dvir; Liu, Wenfang; Drobac, Estelle; Crowder, Melissa E.; Kong, Lingling; Alvarez, Francisco J.; Sumner, Charlotte J.; O'Donovan, Michael J.

2011-01-01

SUMMARY To define alterations of neuronal connectivity that occur during motor neuron degeneration, we characterized the function and structure of spinal circuitry in spinal muscular atrophy (SMA) model mice. SMA motor neurons show reduced proprioceptive reflexes that correlate with decreased number and function of synapses on motor neuron somata and proximal dendrites. These abnormalities occur at an early stage of disease in motor neurons innervating proximal hindlimb muscles and medial motor neurons innervating axial muscles, but only at end-stage disease in motor neurons innervating distal hindlimb muscles. Motor neuron loss follows afferent synapse loss with the same temporal and topographical pattern. Trichostatin A, which improves motor behavior and survival of SMA mice, partially restores spinal reflexes illustrating the reversibility of these synaptic defects. De-afferentation of motor neurons is an early event in SMA and may be a primary cause of motor dysfunction that is amenable to therapeutic intervention. PMID:21315257

Protocol study for a randomised, controlled, double-blind, clinical trial involving virtual reality and anodal transcranial direct current stimulation for the improvement of upper limb motor function in children with Down syndrome.

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Lopes, Jamile Benite Palma; Grecco, Luanda André Collange; Moura, Renata Calhes Franco de; Lazzari, Roberta Delasta; Duarte, Natalia de Almeida Carvalho; Miziara, Isabela; Melo, Gileno Edu Lameira de; Dumont, Arislander Jonathan Lopes; Galli, Manuela; Santos Oliveira, Claudia

2017-08-11

Down syndrome results in neuromotor impairment that affects selective motor control, compromising the acquisition of motor skills and functional independence. The aim of the proposed study is to evaluate and compare the effects of multiple-monopolar anodal transcranial direct current stimulation and sham stimulation over the primary motor cortex during upper limb motor training involving virtual reality on motor control, muscle activity, cerebral activity and functional independence. A randomised, controlled, double-blind, clinical trial is proposed. The calculation of the sample size will be defined based on the results of a pilot study involving the same methods. The participants will be randomly allocated to two groups. Evaluations will be conducted before and after the intervention as well as 1 month after the end of the intervention process. At each evaluation, three-dimensional analysis of upper limb movement muscle activity will be measured using electromyography, cerebral activity will be measured using an electroencephalogram system and intellectual capacity will be assessed using the Wechsler Intelligence Scale for Children. Virtual reality training will be performed three times a week (one 20 min session per day) for a total of 10 sessions. During the protocol, transcranial stimulation will be administered concomitantly to upper limb motor training. The results will be analysed statistically, with a p value≤0.05 considered indicative of statistical significance. The present study received approval from the Institutional Review Board of Universidade Nove de Julho (Sao Paulo,Brazil) under process number 1.540.113 and is registered with the Brazilian Registry of Clinical Trials (N° RBR3PHPXB). The participating institutions have presented a declaration of participation. The volunteers will be permitted to drop out of the study at any time with no negative repercussions. The results will be published and will contribute evidence regarding the use of

Functional compensation of motor function in pre-symptomatic Huntington's disease

DEFF Research Database (Denmark)

Klöppel, Stefan; Draganski, Bogdan; Siebner, Hartwig R

2009-01-01

the compensatory mechanisms that underlie the phenomenon of retained motor function in the presence of degenerative change. Fifteen pre-symptomatic gene carriers and 12 matched controls performed button presses paced by a metronome at either 0.5 or 2 Hz with four fingers of the right hand whilst being scanned...... with functional magnetic resonance imaging. Subjects pressed buttons either in the order of a previously learnt 10-item finger sequence, from left to right, or kept still. Error rates ranged from 2% to 7% in the pre-symptomatic gene carriers and from 0.5% to 4% in controls, depending on the condition...

Task-specific effect of transcranial direct current stimulation on motor learning

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Cinthia Maria Saucedo Marquez

2013-07-01

Full Text Available Transcranial direct current stimulation (tDCS is a relatively new non-invasive brain stimulation technique that modulates neural processes. When applied to the human primary motor cortex (M1, tDCS has beneficial effects on motor skill learning and consolidation in healthy controls and in patients. However, it remains unclear whether tDCS improves motor learning in a general manner or whether these effects depend on which motor task is acquired. Here we compare whether the effect of tDCS differs when the same individual acquires (1 a Sequential Finger Tapping Task (SEQTAP and (2 a Visual Isometric Pinch Force Task (FORCE. Both tasks have been shown to be sensitive to tDCS applied over M1, however, the underlying processes mediating learning and memory formation might benefit differently from anodal-tDCS. Thirty healthy subjects were randomly assigned to an anodal-tDCS group or sham-group. Using a double-blind, sham-controlled cross-over design, tDCS was applied over M1 while subjects acquired each of the motor tasks over 3 consecutive days, with the order being randomized across subjects. We found that anodal-tDCS affected each task differently: The SEQTAP task benefited from anodal-tDCS during learning, whereas the FORCE task showed improvements only at retention. These findings suggest that anodal tDCS applied over M1 appears to have a task-dependent effect on learning and memory formation.

Heavy Chronic Ethanol Exposure From Adolescence to Adulthood Induces Cerebellar Neuronal Loss and Motor Function Damage in Female Rats

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Fernando B. R. da Silva

2018-05-01

Full Text Available Over the last years, heavy ethanol consumption by teenagers/younger adults has increased considerably among females. However, few studies have addressed the long-term impact on brain structures’ morphology and function of chronic exposure to high ethanol doses from adolescence to adulthood in females. In line with this idea, in the current study we investigated whether heavy chronic ethanol exposure during adolescence to adulthood may induce motor impairments and morphological and cellular alterations in the cerebellum of female rats. Adolescent female Wistar rats (35 days old were treated with distilled water or ethanol (6.5 g/kg/day, 22.5% w/v during 55 days by gavage. At 90 days of age, motor function of animals was assessed using open field (OF, pole, beam walking and rotarod tests. Following completion of behavioral tests, morphological and immunohistochemical analyses of the cerebellum were performed. Chronic ethanol exposure impaired significantly motor performance of female rats, inducing spontaneous locomotor activity deficits, bradykinesia, incoordination and motor learning disruption. Moreover, histological analysis revealed that ethanol exposure induced atrophy and neuronal loss in the cerebellum. These findings indicate that heavy ethanol exposure during adolescence is associated with long-lasting cerebellar degeneration and motor impairments in female rats.

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

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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.

A novel solid-state control system for the minimization of re-switching transient currents of induction motor

International Nuclear Information System (INIS)

Abro, M.R.; Larik, A.S.; Mahar, M.A.

2005-01-01

This work is an investigation into the minimizing re-closure transient currents of induction motors by activating NOVEL solid state control system switching at a matched condition. This emphasis is placed upon-circuit transition starting of cage motors, particularly star-delta switching. The initial study is carried out on single-phase induction motion. This system is capable of effective sensing re-closure of a switched off running single-phase induction motor. Further this scheme could be developed to give sequential delta closure of a switched off running three-phase induction motor during 1st cycles following the opening of the star mode. Consideration is also given to the possibility of using sensed re-closure to minimize transient whenever the supply to a running induction motor is briefly interrupted, irrespective of whether the interruption is by accident design. A brief study is made into the type of transient currents generated by opening the circuit of a running induction motor. The importance of the switching pattern for star-delta starting is explained and emphasized. (author)

Motor circuit computer model based on studies of functional Nuclear Magnetic Resonance

International Nuclear Information System (INIS)

Garcia Ramo, Karla Batista; Rodriguez Rojas, Rafael; Carballo Barreda, Maylen

2012-01-01

The basal ganglia are a complex network of subcortical nuclei involved in motor control, sensorimotor integration, and cognitive processes. Their functioning and interaction with other cerebral structures remains as a subject of debate. The aim of the present work was to simulate the basal ganglia-thalamus-cortex circuitry interaction in motor program selection, supported by functional connectivity pattern obtained by functional nuclear magnetic resonance imaging. Determination of connections weights between neural populations by functional magnetic resonance imaging, contributed to a more realistic formulation of the model; and consequently to obtain similar results to clinical and experimental data. The network allowed to describe the participation of the basal ganglia in motor program selection and the changes in Parkinson disease. The simulation allowed to demonstrate that dopamine depletion above to 40 % leads to a loss of action selection capability, and to reflect the system adaptation ability to compensate dysfunction in Parkinson disease, coincident with experimental and clinical studies

Hemispheric surgery for refractory epilepsy in children and adolescents: outcome regarding seizures, motor skills and adaptive function.

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Hamad, Ana Paula; Caboclo, Luís Otávio; Centeno, Ricardo; Costa, Livia Vianez; Ladeia-Frota, Carol; Junior, Henrique Carrete; Gomez, Nicolas Garofalo; Marinho, Murilo; Yacubian, Elza Márcia Targas; Sakamoto, Américo Ceiki

2013-11-01

The aim of the study was to report the seizure outcome, motor skills and adaptive motor functions in a series of children and adolescents who underwent hemispheric surgery, analysing the risk-benefits of surgery. The clinical course, seizure and motor function outcomes of 15 patients who underwent hemispheric surgery were reviewed. The mean age at surgery was 9.5, with 1-9 years follow-up. The underlying pathologies were Rasmussen encephalitis, vascular disorders, and hemimegalencephaly. All the patients presented with severe epilepsy and different degrees of hemiparesis, although motor functionality was preserved in 80% of the patients. At last follow-up, 67% were seizure free, and 20% rarely experienced seizures. Antiepileptic drugs were reduced in 60%, and complete withdrawal from such drugs was successful in 20% of the patients. The motor outcome following the surgery varied between the patients. Despite the motor deficit after surgery, the post-operative motor function showed unchanged for gross motor function in most (60%), while 27% improved. Similar results were obtained for the ability to handle objects in daily life activities. Sixty percent of the children were capable of handling objects, with somewhat reduced coordination and/or motor speed. Pre-surgical motor function continues to play a role in the pre-surgical evaluation process in order to provide a baseline for outcome. Hemispheric surgery, once regarded as a radical intervention and last treatment resource, may become routinely indicated for refractory hemispheric epilepsy in children and adolescents, with oftentime favourable motor outcomes. Copyright © 2013 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Environmental exposure to manganese and motor function of children in Mexico.

Science.gov (United States)

Hernández-Bonilla, D; Schilmann, A; Montes, S; Rodríguez-Agudelo, Y; Rodríguez-Dozal, S; Solís-Vivanco, R; Ríos, C; Riojas-Rodríguez, H

2011-10-01

Occupational manganese (Mn) exposure has been associated with motor deficits in adult workers, but data on the potential effects of environmental exposure to Mn on the developing motor function for a children population is scarce. The aim of this study was to evaluate the association between exposure to Mn and motor function of school aged children. We conducted a cross-sectional study selecting 195 children (100 exposed and 95 unexposed) between 7 and 11 years old. The following tests were used to evaluate the motor function: Grooved pegboard, finger tapping, and Santa Ana test. Mn exposure was assessed by blood (MnB) and hair concentrations (MnH). We constructed linear regression models to evaluate the association between exposure to Mn and the different test scores adjusting for age, sex, maternal education, hemoglobin and blood lead. The median concentration of MnH and MnB was significantly higher in exposed (12.6 μg/g and 9.5 μg/L) compared to unexposed children (0.6 μg/g and 8.0 μg/L). The exposed children on average performed the grooved pegboard test faster, but made more errors, although these results did not reach statistical significance with neither one of the Mn exposure biomarkers. MnB showed an inverse association on the execution of the finger tapping test (average in 5 trials β -0.4, p=0.02), but no association was observed with MnH. A subtle negative association of Mn exposure on motor speed and coordination was shown. In adults, the main effect of environmental Mn exposure has been associated with motor skills, but these results suggest that such alterations are not the main effect on children. Copyright © 2011 Elsevier Inc. All rights reserved.

Fine Motor Skills and Executive Function Both Contribute to Kindergarten Achievement

Science.gov (United States)

Cameron, Claire E.; Brock, Laura L.; Murrah, William M.; Bell, Lindsay H.; Worzalla, Samantha L.; Grissmer, David; Morrison, Frederick J.

2012-01-01

This study examined the contribution of executive function (EF) and multiple aspects of fine motor skills to achievement on 6 standardized assessments in a sample of middle-socioeconomic status kindergarteners. Three- and 4-year-olds' (n = 213) fine and gross motor skills were assessed in a home visit before kindergarten, EF was measured at fall…

Early uneven ear input induces long-lasting differences in left-right motor function.

Science.gov (United States)

Antoine, Michelle W; Zhu, Xiaoxia; Dieterich, Marianne; Brandt, Thomas; Vijayakumar, Sarath; McKeehan, Nicholas; Arezzo, Joseph C; Zukin, R Suzanne; Borkholder, David A; Jones, Sherri M; Frisina, Robert D; Hébert, Jean M

2018-03-01

How asymmetries in motor behavior become established normally or atypically in mammals remains unclear. An established model for motor asymmetry that is conserved across mammals can be obtained by experimentally inducing asymmetric striatal dopamine activity. However, the factors that can cause motor asymmetries in the absence of experimental manipulations to the brain remain unknown. Here, we show that mice with inner ear dysfunction display a robust left or right rotational preference, and this motor preference reflects an atypical asymmetry in cortico-striatal neurotransmission. By unilaterally targeting striatal activity with an antagonist of extracellular signal-regulated kinase (ERK), a downstream integrator of striatal neurotransmitter signaling, we can reverse or exaggerate rotational preference in these mice. By surgically biasing vestibular failure to one ear, we can dictate the direction of motor preference, illustrating the influence of uneven vestibular failure in establishing the outward asymmetries in motor preference. The inner ear-induced striatal asymmetries identified here intersect with non-ear-induced asymmetries previously linked to lateralized motor behavior across species and suggest that aspects of left-right brain function in mammals can be ontogenetically influenced by inner ear input. Consistent with inner ear input contributing to motor asymmetry, we also show that, in humans with normal ear function, the motor-dominant hemisphere, measured as handedness, is ipsilateral to the ear with weaker vestibular input.

Functional magnetic resonance imaging mapping of the motor cortex in patients with cerebral tumors

International Nuclear Information System (INIS)

Mueller, W.M.; Zerrin Yetkin, F.; Hammeke, T.A.

1997-01-01

Objective. The purpose of this study was to determine the usefulness of functional magnetic resonance imaging (FMRI) to map cerebral functions in patients with frontal or parietal tumors. Methods. Charts and images of patients with cerebral tumors or vascular malformations who underwent FMRI with an echo-planar technique were reviewed. The FMRI maps of motor (11 patients), tactile sensory (12 patients) and language tasks (4 patients) were obtained. The location of the FMRI activation and the positive responses to intraoperative cortical stimulation were compared. The reliability of the paradigms for mapping the rolandic cortex was evaluated. Results. Rolandic cortex was activated by tactile tasks in hall 12 patients and by motor tasks in 10 of 11 patients. Language tasks elicited activation in each of the four patients. Activation was obtained within edematous brain and adjacent to tumors. FMRI in three cases with intraoperative electro-cortical mapping results showed activation for a language, tactile, or motor task within the same gyrus in which stimulation elicited a related motor, sensory, or language function. In patients with >2 cm between the margin of the tumor, as revealed by magnetic resonance imaging, and the activation, no decline in motor function occurred from surgical resection. Conclusions. FMRI of tactile, motor, and language tasks is feasible in patients with cerebral tumors. FMRI shows promise as a means of determining the risk of a postoperative motor deficit from surgical resection of frontal or parietal tumors. (authors)

Motor relearning program and Bobath method improve motor function of the upper extremities in patients with stroke

Institute of Scientific and Technical Information of China (English)

Jinjing Liu; Fengsheng Li; Guihua Liu

2006-01-01

BACKGROUND: In the natural evolution of cerebrovascular disease, unconscious use of affected extremity during drug treatment and daily life can improve the function of affected upper extremity partially, but it is very slow and alsc accompanied by the formation of abnormal mode. Therefore, functional training should be emphasized in recovering the motor function of extremity.OBJECTIVE: To observe the effects of combination of motor relearning program and Bobath method on motor function of upper extremity of patients with stroke.DESIGN: Comparison of therapeutic effects taking stroke patients as observation subjects.SETTING: Department of Neurology, General Hospital of Beijing Jingmei Group.PARTICIPANTS: Totally 120 stroke patients, including 60 males and 60 females, averaged (59±3) years, who hospitalized in the Department of Neurology, General Hospital of Beijing Jingmei Group between January 2005 and June 2006 were recruited. The involved patients met the following criteria: Stroke attack within 2 weeks;diagnosis criteria of cerebral hemorrhage or infarction made in the 4th National Cerebrovascular Disease Conference; confirmed by skull CT or MRI; Informed consents of therapeutic regimen were obtained. The patients were assigned into 2 groups according to their wills: rehabilitation group and control group, with 30 males and 30 females in each group. Patients in rehabilitation group averaged (59±2)years old, and those in the control group averaged (58±2)years old.METHODS: ① Patients in two groups received routine treatment in the Department of Neurology. When the vital signs of patients in the rehabilitation group were stable, individualized treatment was conducted by combined application of motor relearning program and Bobath method. Meanwhile, training of activity of daily living was performed according to the disease condition changes of patients at different phases, including the nursing and instruction of body posture, the maintenance of good extremity

Effect of Hippotherapy on Motor Proficiency and Function in Children with Cerebral Palsy Who Walk.

Science.gov (United States)

Champagne, Danielle; Corriveau, Hélène; Dugas, Claude

2017-02-01

To evaluate the effects of hippotherapy on physical capacities of children with cerebral palsy. Thirteen children (4-12 years old) with cerebral palsy classified in Gross Motor Function Classification System Level I or II were included in this prospective quasi-experimental ABA design study. Participants received 10 weeks of hippotherapy (30 min per week). Gross motor function and proficiency were measured with the Bruininks-Oseretski Motor Proficiency short form [BOT2-SF]) and the Gross Motor Function Measure-88 [GMFM-88] (Dimension D and E) twice before the program (T1 and T1'), immediately after (T2), and 10 weeks following the end of the program (T3). Mean scores for dimensions D and E of the GMFM-88 Dimension scores (p = .005) and three out of the eight items of the BOT2-SF (fine motor precision (p = .013), balance (p = .025), and strength (p = .012) improved between baseline and immediately after intervention; mean scores immediately following and 10 weeks following intervention did not differ. Hippotherapy provided by a trained therapist who applies an intense and graded session for 10 weeks can improve body functions and performance of gross motor and fine motor activities in children with cerebral palsy.

Motor performance of children with mild intellectual disability and borderline intellectual functioning

NARCIS (Netherlands)

Vuijk, P. J.; Hartman, E.; Scherder, E.; Visscher, C.

2010-01-01

Background There is a relatively small body of research on the motor performance of children with mild intellectual disabilities (MID) and borderline intellectual functioning (BIF). Adequate levels of motor skills may contribute to lifelong enjoyment of physical activity, participation in sports and

Eigenvector/eigenvalue analysis of a 3D current referential fault detection and diagnosis of an induction motor

International Nuclear Information System (INIS)

Pires, V. Fernao; Martins, J.F.; Pires, A.J.

2010-01-01

In this paper an integrated approach for on-line induction motor fault detection and diagnosis is presented. The need to insure a continuous and safety operation for induction motors involves preventive maintenance procedures combined with fault diagnosis techniques. The proposed approach uses an automatic three step algorithm. Firstly, the induction motor stator currents are measured which will give typical patterns that can be used to identify the fault. Secondly, the eigenvectors/eigenvalues of the 3D current referential are computed. Finally the proposed algorithm will discern if the motor is healthy or not and report the extent of the fault. Furthermore this algorithm is able to identify distinct faults (stator winding faults or broken bars). The proposed approach was experimentally implemented and its performance verified on various types of working conditions.

Motor ability and adaptive function in children with attention deficit hyperactivity disorder

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Hui-Yi Wang

2011-10-01

Full Text Available Attention deficit hyperactivity disorder (ADHD is a common neuropsychiatric disorder. Previous studies have reported that children with ADHD exhibit deficits of adaptive function and insufficient motor ability. The objective of this study was to investigate the association between adaptive function and motor ability in children with ADHD compared with a group of normal children. The study group included 25 children with ADHD (19 boys and 6 girls, aged from 4.6 years to 8.6 years (mean±standard deviation, 6.5±1.2. A group of 24 children without ADHD (normal children were selected to match the children with ADHD on age and gender. The Movement Assessment Battery for Children, which includes three subtests, was used to assess the motor ability of the children of both groups. The Chinese version of Adaptive Behavior Scales, which consists of 12 life domains, was used to assess adaptive function of the children with ADHD. Compared with the normal children, children with ADHD exhibited poorer motor ability on all the three subtests of motor assessment. In the ADHD group, nine (36% children had significant motor impairments and seven (28% were borderline cases. A total of 10 (40% children with ADHD had definite adaptive problems in one or more adaptive domains. With statistically controlling of IQ for the ADHD group, those children with impaired motor ability had significantly poorer behaviors in the adaptive domain of home living (p=0.035. Moreover, children with ADHD who had severely impaired manual dexterity performed worse than the control group in the adaptive domains of home living (r=−0.47, p=0.018, socialization (r=−0.49, p=0.013, and self-direction (r=−0.41, p=0.040. In addition, children with poorer ball skills had worse home living behavior (r=−0.56, p=0.003. Children who had more impaired balance exhibited poorer performance in social behavior (r=−0.41, p=0.040. This study found significant correlation between motor ability and

Rotational hysteresis and eddy current losses in electrical motor stators under non-conventional supply

International Nuclear Information System (INIS)

Bottauscio, Oriano.; Canova, Aldo; Chiampi, Mario; Repetto, Maurizio

2003-01-01

The magnetic analysis of stators of electrical motors is performed through an innovative 2D finite element formulation that takes into account the effects of eddy currents within the laminations by means of a generalized constitutive relationship also including vector hysteresis. This approach is applied to a deep estimation of magnetic flux distribution and magnetic losses in stator of induction motors supplied by high-frequency sinusoidal or six-step voltage sources

Decoupling control of a five-phase fault-tolerant permanent magnet motor by radial basis function neural network inverse

Science.gov (United States)

Chen, Qian; Liu, Guohai; Xu, Dezhi; Xu, Liang; Xu, Gaohong; Aamir, Nazir

2018-05-01

This paper proposes a new decoupled control for a five-phase in-wheel fault-tolerant permanent magnet (IW-FTPM) motor drive, in which radial basis function neural network inverse (RBF-NNI) and internal model control (IMC) are combined. The RBF-NNI system is introduced into original system to construct a pseudo-linear system, and IMC is used as a robust controller. Hence, the newly proposed control system incorporates the merits of the IMC and RBF-NNI methods. In order to verify the proposed strategy, an IW-FTPM motor drive is designed based on dSPACE real-time control platform. Then, the experimental results are offered to verify that the d-axis current and the rotor speed are successfully decoupled. Besides, the proposed motor drive exhibits strong robustness even under load torque disturbance.

Primary motor cortex functionally contributes to language comprehension: An online rTMS study.

Science.gov (United States)

Vukovic, Nikola; Feurra, Matteo; Shpektor, Anna; Myachykov, Andriy; Shtyrov, Yury

2017-02-01

Among various questions pertinent to grounding human cognitive functions in a neurobiological substrate, the association between language and motor brain structures is a particularly debated one in neuroscience and psychology. While many studies support a broadly distributed model of language and semantics grounded, among other things, in the general modality-specific systems, theories disagree as to whether motor and sensory cortex activity observed during language processing is functional or epiphenomenal. Here, we assessed the role of motor areas in linguistic processing by investigating the responses of 28 healthy volunteers to different word types in semantic and lexical decision tasks, following repetitive transcranial magnetic stimulation (rTMS) of primary motor cortex. We found that early rTMS (delivered within 200ms of word onset) produces a left-lateralised and meaning-specific change in reaction speed, slowing down behavioural responses to action-related words, and facilitating abstract words - an effect present only during semantic, but not lexical, decision. We interpret these data in light of action-perception theory of language, bolstering the claim that motor cortical areas play a functional role in language comprehension. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical activity and obesity mediate the association between childhood motor function and adolescents' academic achievement.

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Kantomaa, Marko T; Stamatakis, Emmanuel; Kankaanpää, Anna; Kaakinen, Marika; Rodriguez, Alina; Taanila, Anja; Ahonen, Timo; Järvelin, Marjo-Riitta; Tammelin, Tuija

2013-01-29

The global epidemic of obesity and physical inactivity may have detrimental implications for young people's cognitive function and academic achievement. This prospective study investigated whether childhood motor function predicts later academic achievement via physical activity, fitness, and obesity. The study sample included 8,061 children from the Northern Finland Birth Cohort 1986, which contains data about parent-reported motor function at age 8 y and self-reported physical activity, predicted cardiorespiratory fitness (cycle ergometer test), obesity (body weight and height), and academic achievement (grades) at age 16 y. Structural equation models with unstandardized (B) and standardized (β) coefficients were used to test whether, and to what extent, physical activity, cardiorespiratory fitness, and obesity at age 16 mediated the association between childhood motor function and adolescents' academic achievement. Physical activity was associated with a higher grade-point average, and obesity was associated with a lower grade-point average in adolescence. Furthermore, compromised motor function in childhood had a negative indirect effect on adolescents' academic achievement via physical inactivity (B = -0.023, 95% confidence interval = -0.031, -0.015) and obesity (B = -0.025, 95% confidence interval = -0.039, -0.011), but not via cardiorespiratory fitness. These results suggest that physical activity and obesity may mediate the association between childhood motor function and adolescents' academic achievement. Compromised motor function in childhood may represent an important factor driving the effects of obesity and physical inactivity on academic underachievement.

Physical activity and obesity mediate the association between childhood motor function and adolescents’ academic achievement

Science.gov (United States)

Kantomaa, Marko T.; Stamatakis, Emmanuel; Kankaanpää, Anna; Kaakinen, Marika; Rodriguez, Alina; Taanila, Anja; Ahonen, Timo; Järvelin, Marjo-Riitta; Tammelin, Tuija

2013-01-01

The global epidemic of obesity and physical inactivity may have detrimental implications for young people’s cognitive function and academic achievement. This prospective study investigated whether childhood motor function predicts later academic achievement via physical activity, fitness, and obesity. The study sample included 8,061 children from the Northern Finland Birth Cohort 1986, which contains data about parent-reported motor function at age 8 y and self-reported physical activity, predicted cardiorespiratory fitness (cycle ergometer test), obesity (body weight and height), and academic achievement (grades) at age 16 y. Structural equation models with unstandardized (B) and standardized (β) coefficients were used to test whether, and to what extent, physical activity, cardiorespiratory fitness, and obesity at age 16 mediated the association between childhood motor function and adolescents’ academic achievement. Physical activity was associated with a higher grade-point average, and obesity was associated with a lower grade-point average in adolescence. Furthermore, compromised motor function in childhood had a negative indirect effect on adolescents’ academic achievement via physical inactivity (B = –0.023, 95% confidence interval = –0.031, –0.015) and obesity (B = –0.025, 95% confidence interval = –0.039, –0.011), but not via cardiorespiratory fitness. These results suggest that physical activity and obesity may mediate the association between childhood motor function and adolescents’ academic achievement. Compromised motor function in childhood may represent an important factor driving the effects of obesity and physical inactivity on academic underachievement. PMID:23277558

Effect of α7 nicotinic acetylcholine receptor agonists and antagonists on motor function in mice

International Nuclear Information System (INIS)

Welch, Kevin D.; Pfister, James A.; Lima, Flavia G.; Green, Benedict T.; Gardner, Dale R.

2013-01-01

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated cation channels found throughout the body, and serve to mediate diverse physiological functions. Muscle-type nAChRs located in the motor endplate region of muscle fibers play an integral role in muscle contraction and thus motor function. The toxicity and teratogenicity of many plants (which results in millions of dollars in losses annually to the livestock industry) are due to various toxins that bind to nAChRs including deltaline and methyllycaconitine (MLA) from larkspur (Delphinium) species, and nicotine and anabasine from tobacco (Nicotiana) species. The primary result of the actions of these alkaloids at nAChRs is neuromuscular paralysis and respiratory failure. The objective of this study was to further characterize the motor coordination deficiencies that occur upon exposure to a non-lethal dose of nAChR antagonists MLA and deltaline as well as nAChR agonists nicotine and anabasine. We evaluated the effect of nAChR agonists and antagonists on the motor function and coordination in mice using a balance beam, grip strength meter, rotarod, open field analysis and tremor monitor. These analyses demonstrated that within seconds after treatment the mice had significant loss of motor function and coordination that lasted up to 1 min, followed by a short period of quiescence. Recovery to normal muscle coordination was rapid, typically within approximately 10 min post-dosing. However, mice treated with the nAChR agonist nicotine and anabasine required a slightly longer time to recover some aspects of normal muscle function in comparison to mice treated with the nAChR antagonist MLA or deltaline. -- Highlights: ► Mice treated with nAChR agonists and antagonists have a loss in motor function. ► These deficits are temporary as near normal motor function returns within 10 min. ► There are compound-specific differences in the effects on motor function.

Tracking the Re-organization of Motor Functions After Disconnective Surgery: A Longitudinal fMRI and DTI Study

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Cristina Rosazza

2018-06-01

Full Text Available Objective: Mechanisms of motor plasticity are critical to maintain motor functions after cerebral damage. This study explores the mechanisms of motor reorganization occurring before and after surgery in four patients with drug-refractory epilepsy candidate to disconnective surgery.Methods: We studied four patients with early damage, who underwent tailored hemispheric surgery in adulthood, removing the cortical motor areas and disconnecting the corticospinal tract (CST from the affected hemisphere. Motor functions were assessed clinically, with functional MRI (fMRI tasks of arm and leg movement and Diffusion Tensor Imaging (DTI before and after surgery with assessments of up to 3 years. Quantifications of fMRI motor activations and DTI fractional anisotropy (FA color maps were performed to assess the lateralization of motor network. We hypothesized that lateralization of motor circuits assessed preoperatively with fMRI and DTI was useful to evaluate the motor outcome in these patients.Results: In two cases preoperative DTI-tractography did not reconstruct the CST, and FA-maps were strongly asymmetric. In the other two cases, the affected CST appeared reduced compared to the contralateral one, with modest asymmetry in the FA-maps. fMRI showed different degrees of lateralization of the motor network and the SMA of the intact hemisphere was mostly engaged in all cases. After surgery, patients with a strongly lateralized motor network showed a stable performance. By contrast, a patient with a more bilateral pattern showed worsening of the upper limb function. For all cases, fMRI activations shifted to the intact hemisphere. Structural alterations of motor circuits, observed with FA values, continued beyond 1 year after surgery.Conclusion: In our case series fMRI and DTI could track the longitudinal reorganization of motor functions. In these four patients the more the paretic limbs recruited the intact hemisphere in primary motor and associative

Tracking the Re-organization of Motor Functions After Disconnective Surgery: A Longitudinal fMRI and DTI Study.

Science.gov (United States)

Rosazza, Cristina; Deleo, Francesco; D'Incerti, Ludovico; Antelmi, Luigi; Tringali, Giovanni; Didato, Giuseppe; Bruzzone, Maria G; Villani, Flavio; Ghielmetti, Francesco

2018-01-01

Objective: Mechanisms of motor plasticity are critical to maintain motor functions after cerebral damage. This study explores the mechanisms of motor reorganization occurring before and after surgery in four patients with drug-refractory epilepsy candidate to disconnective surgery. Methods: We studied four patients with early damage, who underwent tailored hemispheric surgery in adulthood, removing the cortical motor areas and disconnecting the corticospinal tract (CST) from the affected hemisphere. Motor functions were assessed clinically, with functional MRI (fMRI) tasks of arm and leg movement and Diffusion Tensor Imaging (DTI) before and after surgery with assessments of up to 3 years. Quantifications of fMRI motor activations and DTI fractional anisotropy (FA) color maps were performed to assess the lateralization of motor network. We hypothesized that lateralization of motor circuits assessed preoperatively with fMRI and DTI was useful to evaluate the motor outcome in these patients. Results: In two cases preoperative DTI-tractography did not reconstruct the CST, and FA-maps were strongly asymmetric. In the other two cases, the affected CST appeared reduced compared to the contralateral one, with modest asymmetry in the FA-maps. fMRI showed different degrees of lateralization of the motor network and the SMA of the intact hemisphere was mostly engaged in all cases. After surgery, patients with a strongly lateralized motor network showed a stable performance. By contrast, a patient with a more bilateral pattern showed worsening of the upper limb function. For all cases, fMRI activations shifted to the intact hemisphere. Structural alterations of motor circuits, observed with FA values, continued beyond 1 year after surgery. Conclusion: In our case series fMRI and DTI could track the longitudinal reorganization of motor functions. In these four patients the more the paretic limbs recruited the intact hemisphere in primary motor and associative areas, the

On the functional organization and operational principles of the motor cortex

DEFF Research Database (Denmark)

Capaday, Charles; Ethier, Christian; Van Vreeswijk, Carl

2013-01-01

of the movements evoked by activation of each point on its own. This operational principle may simplify the synthesis of motor commands. We will discuss two possible mechanisms that may explain linear summation of outputs. We have observed that the final posture of the arm when pointing to a given spatial location......Recent studies on the functional organization and operational principles of the motor cortex (MCx), taken together, strongly support the notion that the MCx controls the muscle synergies subserving movements in an integrated manner. For example, during pointing the shoulder, elbow and wrist muscles...... appear to be controlled as a coupled functional system, rather than singly and separately. The recurrent pattern of intrinsic synaptic connections between motor cortical points is likely part of the explanation for this operational principle. So too is the reduplicated, non-contiguous and intermingled...

Functional organization and restoration of the brain motor-execution network after stroke and rehabilitation

Directory of Open Access Journals (Sweden)

Sahil eBajaj

2015-03-01

Full Text Available Multiple cortical areas of the human brain motor system interact coherently in the low frequency range (< 0.1 Hz, even in the absence of explicit tasks. Following stroke, cortical interactions are functionally disturbed. How these interactions are affected and how the functional organization is regained from rehabilitative treatments as people begin to recover motor behaviors has not been systematically studied. We recorded the intrinsic functional magnetic resonance imaging (fMRI signals from 30 participants: 17 young healthy controls and 13 aged stroke survivors. Stroke participants underwent mental practice (MP or both mental practice and physical therapy (MP + PT within 14-51 days following stroke. We investigated the network activity of five core areas in the motor-execution network, consisting of the left primary motor area (LM1, the right primary motor area (RM1, the left pre-motor cortex (LPMC, the right pre-motor cortex (RPMC and the supplementary motor area (SMA. We discovered that (i the network activity dominated in the frequency range 0.06 Hz – 0.08 Hz for all the regions, and for both able-bodied and stroke participants (ii the causal information flow between the regions: LM1 and SMA, RPMC and SMA, RPMC and LM1, SMA and RM1, SMA and LPMC, was reduced significantly for stroke survivors (iii the flow did not increase significantly after MP alone and (iv the flow among the regions during MP+PT increased significantly. We also found that sensation and motor scores were significantly higher and correlated with directed functional connectivity measures when the stroke-survivors underwent MP+PT but not MP alone. The findings provide evidence that a combination of mental practice and physical therapy can be an effective means of treatment for stroke survivors to recover or regain the strength of motor behaviors, and that the spectra of causal information flow can be used as a reliable biomarker for evaluating rehabilitation in stroke

Changes in visual and sensory-motor resting-state functional connectivity support motor learning by observing

Science.gov (United States)

McGregor, Heather R.

2015-01-01

Motor learning occurs not only through direct first-hand experience but also through observation (Mattar AA, Gribble PL. Neuron 46: 153–160, 2005). When observing the actions of others, we activate many of the same brain regions involved in performing those actions ourselves (Malfait N, Valyear KF, Culham JC, Anton JL, Brown LE, Gribble PL. J Cogn Neurosci 22: 1493–1503, 2010). Links between neural systems for vision and action have been reported in neurophysiological (Strafella AP, Paus T. Neuroreport 11: 2289–2292, 2000; Watkins KE, Strafella AP, Paus T. Neuropsychologia 41: 989–994, 2003), brain imaging (Buccino G, Binkofski F, Fink GR, Fadiga L, Fogassi L, Gallese V, Seitz RJ, Zilles K, Rizzolatti G, Freund HJ. Eur J Neurosci 13: 400–404, 2001; Iacoboni M, Woods RP, Brass M, Bekkering H, Mazziotta JC, Rizzolatti G. Science 286: 2526–2528, 1999), and eye tracking (Flanagan JR, Johansson RS. Nature 424: 769–771, 2003) studies. Here we used a force field learning paradigm coupled with resting-state fMRI to investigate the brain areas involved in motor learning by observing. We examined changes in resting-state functional connectivity (FC) after an observational learning task and found a network consisting of V5/MT, cerebellum, and primary motor and somatosensory cortices in which changes in FC were correlated with the amount of motor learning achieved through observation, as assessed behaviorally after resting-state fMRI scans. The observed FC changes in this network are not due to visual attention to motion or observation of movement errors but rather are specifically linked to motor learning. These results support the idea that brain networks linking action observation and motor control also facilitate motor learning. PMID:25995349

Changes in visual and sensory-motor resting-state functional connectivity support motor learning by observing.

Science.gov (United States)

McGregor, Heather R; Gribble, Paul L

2015-07-01

Motor learning occurs not only through direct first-hand experience but also through observation (Mattar AA, Gribble PL. Neuron 46: 153-160, 2005). When observing the actions of others, we activate many of the same brain regions involved in performing those actions ourselves (Malfait N, Valyear KF, Culham JC, Anton JL, Brown LE, Gribble PL. J Cogn Neurosci 22: 1493-1503, 2010). Links between neural systems for vision and action have been reported in neurophysiological (Strafella AP, Paus T. Neuroreport 11: 2289-2292, 2000; Watkins KE, Strafella AP, Paus T. Neuropsychologia 41: 989-994, 2003), brain imaging (Buccino G, Binkofski F, Fink GR, Fadiga L, Fogassi L, Gallese V, Seitz RJ, Zilles K, Rizzolatti G, Freund HJ. Eur J Neurosci 13: 400-404, 2001; Iacoboni M, Woods RP, Brass M, Bekkering H, Mazziotta JC, Rizzolatti G. Science 286: 2526-2528, 1999), and eye tracking (Flanagan JR, Johansson RS. Nature 424: 769-771, 2003) studies. Here we used a force field learning paradigm coupled with resting-state fMRI to investigate the brain areas involved in motor learning by observing. We examined changes in resting-state functional connectivity (FC) after an observational learning task and found a network consisting of V5/MT, cerebellum, and primary motor and somatosensory cortices in which changes in FC were correlated with the amount of motor learning achieved through observation, as assessed behaviorally after resting-state fMRI scans. The observed FC changes in this network are not due to visual attention to motion or observation of movement errors but rather are specifically linked to motor learning. These results support the idea that brain networks linking action observation and motor control also facilitate motor learning. Copyright © 2015 the American Physiological Society.

Dysfunction in endoplasmic reticulum-mitochondria crosstalk underlies SIGMAR1 loss of function mediated motor neuron degeneration.

Science.gov (United States)

Bernard-Marissal, Nathalie; Médard, Jean-Jacques; Azzedine, Hamid; Chrast, Roman

2015-04-01

Mutations in Sigma 1 receptor (SIGMAR1) have been previously identified in patients with amyotrophic lateral sclerosis and disruption of Sigmar1 in mouse leads to locomotor deficits. However, cellular mechanisms underlying motor phenotypes in human and mouse with disturbed SIGMAR1 function have not been described so far. Here we used a combination of in vivo and in vitro approaches to investigate the role of SIGMAR1 in motor neuron biology. Characterization of Sigmar1(-/-) mice revealed that affected animals display locomotor deficits associated with muscle weakness, axonal degeneration and motor neuron loss. Using primary motor neuron cultures, we observed that pharmacological or genetic inactivation of SIGMAR1 led to motor neuron axonal degeneration followed by cell death. Disruption of SIGMAR1 function in motor neurons disturbed endoplasmic reticulum-mitochondria contacts, affected intracellular calcium signalling and was accompanied by activation of endoplasmic reticulum stress and defects in mitochondrial dynamics and transport. These defects were not observed in cultured sensory neurons, highlighting the exacerbated sensitivity of motor neurons to SIGMAR1 function. Interestingly, the inhibition of mitochondrial fission was sufficient to induce mitochondria axonal transport defects as well as axonal degeneration similar to the changes observed after SIGMAR1 inactivation or loss. Intracellular calcium scavenging and endoplasmic reticulum stress inhibition were able to restore mitochondrial function and consequently prevent motor neuron degeneration. These results uncover the cellular mechanisms underlying motor neuron degeneration mediated by loss of SIGMAR1 function and provide therapeutically relevant insight into motor neuronal diseases. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Running exercise enhances motor functional recovery with inhibition of dendritic regression in the motor cortex after collagenase-induced intracerebral hemorrhage in rats.

Science.gov (United States)

Takamatsu, Yasuyuki; Tamakoshi, Keigo; Waseda, Yuya; Ishida, Kazuto

2016-03-01

Rehabilitative approaches benefit motor functional recovery after stroke and relate to neuronal plasticity. We investigated the effects of a treadmill running exercise on the motor functional recovery and neuronal plasticity after collagenase-induced striatal intracerebral hemorrhage (ICH) in rats. Male Wistar rats were injected with type IV collagenase into the left striatum to induce ICH. Sham-operated animals were injected with saline instead of collagenase. The animals were randomly assigned to the sham control (SC), the sham exercise (SE), the ICH control (IC), or the ICH exercise (IE) group. The exercise groups were forced to run on a treadmill at a speed of 9 m/min for 30 min/day between days 4 and 14 after surgery. Behavioral tests were performed using a motor deficit score, a beam-walking test and a cylinder test. At fifteen days after surgery, the animals were sacrificed, and their brains were removed. The motor function of the IE group significantly improved compared with the motor function of the IC group. No significant differences in cortical thickness were found between the groups. The IC group had fewer branches and shorter dendrite lengths compared with the sham groups. However, dendritic branches and lengths were not significantly different between the IE and the other groups. Tropomyosin-related kinase B (TrkB) expression levels increased in the IE compared with IC group, but no significant differences in other protein (brain-derived neurotrophic factor, BDNF; Nogo-A; Rho-A/Rho-associated protein kinase 2, ROCK2) expression levels were found between the groups. These results suggest that improved motor function after a treadmill running exercise after ICH may be related to the prevention of dendritic regression due to TrkB upregulation. Copyright © 2015. Published by Elsevier B.V.

Human brain mapping of language-related function on 1.5T magnetic resonance system: focused on motor language function

International Nuclear Information System (INIS)

Jung, Hee Young; Kim, Jae Hyoung; Shin, Taemin; Piao, Xiang Hao; Kim, Jae Soo; Lee, Gyung Kyu; Park, Il Soon; Park, Ji Hoon; Kang, Su Jin; You, Jin Jong; Chung, Sung Hoon

1998-01-01

To investigate the feasibility of functional MR imaging of motor language function and its usefulness in the determination of hemispheric language dominance. In order to activate the motor center of language, six subjects ( 5 right-handed, 1 left-handed: 3 males: 3 females) generated words. They were requested to do this silently, without physical articulation, in response to English letters presented visually. Gradient-echo images (TR/TE/flip angle, 80/60/40 deg; 64 x 128 matrix; 10 mm thickness) were obtained in three axial planes including the inferior frontal gyrus. Functional maps were created by the postprocessing of gradient-echo images, including subtraction and statistics. Areas of activation were topographically analyzed and numbers of activated pixels in each region were compared between right and left sides. The reproducibility of functional maps was tested by repetition of functional imaging in the same subjects. Our results suggest that functional MR imaging can depict the activation of motor language function in the brain and can be used a useful non-invasive method for determining the hemispheric dominance of language. (author). 26 refs., 3 figs

Association between vestibular function and motor performance in hearing-impaired children.

Science.gov (United States)

Maes, Leen; De Kegel, Alexandra; Van Waelvelde, Hilde; Dhooge, Ingeborg

2014-12-01

The clinical balance performance of normal-hearing (NH) children was compared with the balance performance of hearing-impaired (HI) children with and without vestibular dysfunction to identify an association between vestibular function and motor performance. Prospective study. Tertiary referral center. Thirty-six children (mean age, 7 yr 5 mo; range, 3 yr 8 mo-12 yr 11 mo) divided into three groups: NH children with normal vestibular responses, HI children with normal vestibular responses, and HI children with abnormal vestibular function. A vestibular test protocol (rotatory and collic vestibular evoked myogenic potential testing) in combination with three clinical balance tests (balance beam walking, one-leg hopping, one-leg stance). Clinical balance performance. HI children with abnormal vestibular test results obtained the lowest quotients of motor performance, which were significantly lower compared with the NH group (p beam walking and one-leg stance; p = 0.003 for one-leg hopping). The balance performance of the HI group with normal vestibular responses was better in comparison with the vestibular impaired group but still significantly lower compared with the NH group (p = 0.020 for balance beam walking; p = 0.001 for one-leg stance; not significant for one-leg hopping). These results indicate an association between vestibular function and motor performance in HI children, with a more distinct motor deterioration if a vestibular impairment is superimposed to the auditory dysfunction.

[Formula: see text]Current knowledge on motor disorders in children with autism spectrum disorder (ASD).

Science.gov (United States)

Paquet, A; Olliac, B; Golse, B; Vaivre-Douret, L

2016-01-01

Motor symptomatology in autism is currently poorly understood, and still not included in the autism spectrum disorder (ASD) diagnostic criteria, although some studies suggest the presence of motor disturbances in this syndrome. We provide here a literature review on early motor symptoms in autism, focusing on studies on psychomotor issues (tone, postural control, manual dexterity, handedness, praxis). The approach adopted in research to study altered motor behaviors is generally global and there is no detailed semiology of the motor or neuromotor disorders observed in people with ASD. This global approach does not enable understanding of the neuro-developmental mechanisms involved in ASD. Identification of clinical neuro-psychomotor profiles in reference to a standard would help to better understand the origin and the nature of the disorders encountered in ASD, and would thus give new directions for treatment.

The sensory side of post-stroke motor rehabilitation.

Science.gov (United States)

Bolognini, Nadia; Russo, Cristina; Edwards, Dylan J

2016-04-11

Contemporary strategies to promote motor recovery following stroke focus on repetitive voluntary movements. Although successful movement relies on efficient sensorimotor integration, functional outcomes often bias motor therapy toward motor-related impairments such as weakness, spasticity and synergies; sensory therapy and reintegration is implied, but seldom targeted. However, the planning and execution of voluntary movement requires that the brain extracts sensory information regarding body position and predicts future positions, by integrating a variety of sensory inputs with ongoing and planned motor activity. Neurological patients who have lost one or more of their senses may show profoundly affected motor functions, even if muscle strength remains unaffected. Following stroke, motor recovery can be dictated by the degree of sensory disruption. Consequently, a thorough account of sensory function might be both prognostic and prescriptive in neurorehabilitation. This review outlines the key sensory components of human voluntary movement, describes how sensory disruption can influence prognosis and expected outcomes in stroke patients, reports on current sensory-based approaches in post-stroke motor rehabilitation, and makes recommendations for optimizing rehabilitation programs based on sensory stimulation.

Relationship between communication skills and gross motor function in preschool-aged children with cerebral palsy.

Science.gov (United States)

Coleman, Andrea; Weir, Kelly A; Ware, Robert S; Boyd, Roslyn N

2013-11-01

To explore the communication skills of children with cerebral palsy (CP) at 24 months' corrected age with reference to typically developing children, and to determine the relationship between communication ability, gross motor function, and other comorbidities associated with CP. Prospective, cross-sectional, population-based cohort study. General community. Children with CP (N=124; mean age, 24mo; functional severity on Gross Motor Function Classification System [GMFCS]: I=47, II=14, III=22, IV=19, V=22). Not applicable. Parents reported communication skills on the Communication and Symbolic Behavior Scales Developmental Profile (CSBS-DP) Infant-Toddler Checklist. Two independent physiotherapists classified motor type, distribution, and GMFCS. Data on comorbidities were obtained from parent interviews and medical records. Children with mild CP (GMFCS I/II) had mean CSBS-DP scores that were 0.5 to 0.6 SD below the mean for typically developing peers, while those with moderate-severe impairment (GMFCS III-V) were 1.4 to 2.6 SD below the mean. GMFCS was significantly associated with performance on the CSBS-DP (F=18.55, Pgross motor ability accounting for 38% of the variation in communication. Poorer communication was strongly associated with gross motor function and full-term birth. Preschool-aged children with CP, with more severe gross motor impairment, showed delayed communication, while children with mild motor impairment were less vulnerable. Term-born children had significantly poorer communication than those born prematurely. Because a portion of each gross motor functional severity level is at risk, this study reinforces the need for early monitoring of communication development for all children with CP. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Impairment of complex upper limb motor function in de novo parkinson's disease.

NARCIS (Netherlands)

Ponsen, M.M.; Daffertshofer, A.; Wolters, E.C.M.J.; Beek, P.J.; Berendse, H.W.

2008-01-01

The aim of the present study was to evaluate complex upper limb motor function in newly diagnosed, untreated Parkinson's disease (PD) patients. Four different unimanual upper limb motor tasks were applied to 13 newly diagnosed, untreated PD patients and 13 age- and sex-matched controls. In a

Impact of a Community-Based Programme for Motor Development on Gross Motor Skills and Cognitive Function in Preschool Children from Disadvantaged Settings

Science.gov (United States)

Draper, Catherine E.; Achmat, Masturah; Forbes, Jared; Lambert, Estelle V.

2012-01-01

The aims of the studies were to assess the impact of the Little Champs programme for motor development on (1) the gross motor skills, and (2) cognitive function of children in the programme. In study 1, 118 children from one Early Childhood Development Centre (ECDC) were tested using the Test of Gross Motor Development-2, and in study 2, 83…

The Inpatient Assessment and Management of Motor Functional Neurological Disorders: An Interdisciplinary Perspective.

Science.gov (United States)

McKee, Kathleen; Glass, Sean; Adams, Caitlin; Stephen, Christopher D; King, Franklin; Parlman, Kristin; Perez, David L; Kontos, Nicholas

2018-01-08

Motor functional neurologic disorders (FND)-previously termed "hysteria" and later "conversion disorder"-are exceedingly common and frequently encountered in the acute hospital setting. Despite their high prevalence, patients with motor FND can be challenging to diagnose accurately and manage effectively. To date, there is limited guidance on the inpatient approach to the neuropsychiatric evaluation of patients with functional (psychogenic) neurologic symptoms. The authors outline an inpatient multidisciplinary approach, involving neurology, psychiatry, and physical therapy, for the assessment and acute inpatient management of motor FND. A vignette of a patient with motor FND is presented followed by a discussion of general assessment principles. Thereafter, a detailed description of the neurologic and psychiatric assessments is outlined. Delivery of a "rule-in" diagnosis is emphasized and specific guidance for what can be accomplished postdiagnosis in the hospital is suggested. We encourage an interdisciplinary approach beginning at the early stages of the diagnostic assessment once an individual is suspected of having motor FND. Practical suggestions for the inpatient assessment of motor FND are presented. It is also important to individualize the diagnostic assessment. Future research should be conducted to test best practices for motor FND management in the acute inpatient hospital setting. Copyright © 2018 Academy of Consultation-Liaison Psychiatry. Published by Elsevier Inc. All rights reserved.

Fine motor skills and executive function both contribute to kindergarten achievement

Science.gov (United States)

Cameron, Claire E.; Brock, Laura L.; Murrah, William M.; Bell, Lindsay H.; Worzalla, Samantha L.; Grissmer, David; Morrison, Frederick J.

2012-01-01

This study examined the contribution of executive function (EF) and multiple aspects of fine motor skills to achievement on six standardized assessments in a sample of middle-SES kindergarteners. 3- and 4-year-olds’ (N=213) fine and gross motor skills were assessed in a home visit before kindergarten; EF was measured at fall of kindergarten; and Woodcock-Johnson III (WJ III) Tests of Academic Achievement were administered at fall and spring. Correlations indicated that EF and fine motor skills appeared distinct. Further, controlling for background variables, higher levels of both EF and fine motor skills, specifically design copy, predicted higher achievement on multiple subtests at kindergarten entry, as well as improvement from fall to spring. Implications for research on school readiness are discussed. PMID:22537276

Motor Performance of Children with Mild Intellectual Disability and Borderline Intellectual Functioning

Science.gov (United States)

Vuijk, P. J.; Hartman, E.; Scherder, E.; Visscher, C.

2010-01-01

Background: There is a relatively small body of research on the motor performance of children with mild intellectual disabilities (MID) and borderline intellectual functioning (BIF). Adequate levels of motor skills may contribute to lifelong enjoyment of physical activity, participation in sports and healthy lifestyles. The present study compares…

Functional resting-state connectivity of the human motor network: differences between right- and left-handers.

Science.gov (United States)

Pool, Eva-Maria; Rehme, Anne K; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

2015-04-01

Handedness is associated with differences in activation levels in various motor tasks performed with the dominant or non-dominant hand. Here we tested whether handedness is reflected in the functional architecture of the motor system even in the absence of an overt motor task. Using resting-state functional magnetic resonance imaging we investigated 18 right- and 18 left-handers. Whole-brain functional connectivity maps of the primary motor cortex (M1), supplementary motor area (SMA), dorsolateral premotor cortex (PMd), pre-SMA, inferior frontal junction and motor putamen were compared between right- and left-handers. We further used a multivariate linear support vector machine (SVM) classifier to reveal the specificity of brain regions for classifying handedness based on individual resting-state maps. Using left M1 as seed region, functional connectivity analysis revealed stronger interhemispheric functional connectivity between left M1 and right PMd in right-handers as compared to left-handers. This connectivity cluster contributed to the individual classification of right- and left-handers with 86.2% accuracy. Consistently, also seeding from right PMd yielded a similar handedness-dependent effect in left M1, albeit with lower classification accuracy (78.1%). Control analyses of the other resting-state networks including the speech and the visual network revealed no significant differences in functional connectivity related to handedness. In conclusion, our data revealed an intrinsically higher functional connectivity in right-handers. These results may help to explain that hand preference is more lateralized in right-handers than in left-handers. Furthermore, enhanced functional connectivity between left M1 and right PMd may serve as an individual marker of handedness. Copyright © 2015 Elsevier Inc. All rights reserved.

Motor network plasticity and low-frequency oscillations abnormalities in patients with brain gliomas: a functional MRI study.

Directory of Open Access Journals (Sweden)

Chen Niu

Full Text Available Brain plasticity is often associated with the process of slow-growing tumor formation, which remodels neural organization and optimizes brain network function. In this study, we aimed to investigate whether motor function plasticity would display deficits in patients with slow-growing brain tumors located in or near motor areas, but who were without motor neurological deficits. We used resting-state functional magnetic resonance imaging to probe motor networks in 15 patients with histopathologically confirmed brain gliomas and 15 age-matched healthy controls. All subjects performed a motor task to help identify individual motor activity in the bilateral primary motor cortex (PMC and supplementary motor area (SMA. Frequency-based analysis at three different frequencies was then used to investigate possible alterations in the power spectral density (PSD of low-frequency oscillations. For each group, the average PSD was determined for each brain region and a nonparametric test was performed to determine the difference in power between the two groups. Significantly reduced inter-hemispheric functional connectivity between the left and right PMC was observed in patients compared with controls (P<0.05. We also found significantly decreased PSD in patients compared to that in controls, in all three frequency bands (low: 0.01-0.02 Hz; middle: 0.02-0.06 Hz; and high: 0.06-0.1 Hz, at three key motor regions. These findings suggest that in asymptomatic patients with brain tumors located in eloquent regions, inter-hemispheric connection may be more vulnerable. A comparison of the two approaches indicated that power spectral analysis is more sensitive than functional connectivity analysis for identifying the neurological abnormalities underlying motor function plasticity induced by slow-growing tumors.

Performance evaluation of directly photovoltaic powered DC PM (direct current permanent magnet) motor – propeller thrust system

International Nuclear Information System (INIS)

Atlam, Ozcan; Kolhe, Mohan

2013-01-01

Photovoltaic (PV) powered directly coupled electro-mechanical system has wide applications (e.g. PV powered cooling fans in green houses, PV water pumping system, solar vehicles). The objective of this work is to analyse the operation of directly PV powered DC PM (direct current permanent magnet) motor – propeller system for selection of motor parameters. The performance of such system mainly depends on the incident solar radiation, operating cell temperature, DC motor and propeller load parameters. It is observed that the operating points of the PV DC PM motor – propeller system matches very closely with the maximum power points (MPPs) of the PV array, if the DC PM motor – propeller parameters have been properly selected. It is found that for a specific application of such type of system, matching of torque–speed operating points with respect to the maximum power points of PV array are very important. It is ascertained through results that the DC PM motor's armature resistance, magnetic field constant, starting current to overcome the starting torque and torque coefficient are the main parameters. In designing a PV powered DC PM motor for a specific application, selection of these parameters are important for maximum utilization of the PV array output. The results of this system are useful for designing of directly PV powered DC PM motor's for aerodynamic applications. - Highlights: • We analyse the performance of directly PV powered DC PM motor – propeller system. • We examine PV electro-mechanical system for selection of DC motor parameters. • Matching of torque–speed curve to maximum power points of PV array is important

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...... 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....

The Written-Pole{sup TM} motor: high efficiency - low start current

Energy Technology Data Exchange (ETDEWEB)

Beck, B. [C.Eng. Precise Power Corp., Bradenton, FL (United States); Friesen, D. [P.E. Manitoba Hydro, Winnipeg (Canada)

2000-07-01

Written-Pole{sup TM} technology is a patented machine technology, which changes the magnetic polarity of the rotor field in a rotating machine, while the machine is operating. The number of poles is thereby changed, resulting in a constant frequency - variable speed machine. When operating as a motor, a Written-Pole machine has inherently low starting current and high operating efficiency. (orig.)

A Recommended New Approach on Motorization Ratio Calculations of Stepper Motors

Science.gov (United States)

Nalbandian, Ruben; Blais, Thierry; Horth, Richard

2014-01-01

Stepper motors are widely used on most spacecraft mechanisms requiring repeatable and reliable performance. The unique detent torque characteristics of these type of motors makes them behave differently when subjected to low duty cycle excitations where the applied driving pulses are only energized for a fraction of the pulse duration. This phenomenon is even more pronounced in discrete permanent magnet stepper motors used in the space industry. While the inherent high detent properties of discrete permanent magnets provide desirable unpowered holding performance characteristics, it results in unique behavior especially in low duty cycles. Notably, the running torque reduces quickly to the unpowered holding torque when the duty cycle is reduced. The space industry's accepted methodology of calculating the Motorization Ratio (or Torque Margin) is more applicable to systems where the power is continuously applied to the motor coils like brushless DC motors where the cogging torques are low enough not to affect the linear performance of the motors as a function of applied current. This paper summarizes the theoretical and experimental studies performed on a number of space qualified motors under different pulse rates and duty cycles. It is the intention of this paper to introduce a new approach to calculate the Motorization Ratios for discrete permanent magnet steppers under all full and partial duty cycle regimes. The recommended approach defines two distinct relationships to calculate the Motorization Ratio for 100 percent duty cycle and partial duty cycle, when the motor detent (unpowered holding torque) is the main contributor to holding position. These two computations reflect accurately the stepper motor physical behavior as a function of the command phase (ON versus OFF times of the pulses), pointing out how the torque contributors combine. Important points highlighted under this study are the torque margin computations, in particular for well characterized

Parental questionnaire as a screening instrument for motor function at age five.

Science.gov (United States)

Nordbye-Nielsen, Kirsten; Kesmodel, Ulrik Schiøler

2014-12-01

No standardised method is used to determine motor function in children in general practice in Denmark. Our aim was to evaluate the correlation between a parental questionnaire assessing motor function at the age of five years and the clinical test Movement Assessment Battery for Children (M-ABC), and to assess whether one or more questions could be used to screen for motor problems at the age of five years. This study was based on a parental questionnaire containing ten questions. The M-ABC was used as the gold standard. n = 755 children. The Mann-Whitney rank sum test, Pearson's χ(2)-test, logistic regression analyses and sensitivity and specificity were used to assess the correlation between the questionnaire and the M-ABC test. The best screening tool was six questions in combination: sensitivity 39.8%, specificity 87.1%. Asking if a health professional ever expressed concern about the childs motor development had a sensitivity of 17.0% and a specificity of 93.9%. A parental questionnaire used as a screening instrument to identify children with motor problems has a reasonable specificity, but a low sensitivity. The six questions can be used to identify children who do not have motor function difficulties with a relatively high certainty, and it can fairly well identify children with motor function problems. This study was primarily supported by the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA. Additional support was obtained from The Danish Health and Medicines Authority, the Lundbeck Foundation, Ludvig & Daara Elsass Foundation, the Augustinus Foundation, and Aase & Ejnar Danielsens Foundation. The Danish National Research Foundation has established the Danish Epidemiology Science Centre that initiated and created the Danish National Birth Cohort. The cohort is furthermore a result of a major grant from this Foundation. Additional support for the Danish National Birth Cohort is obtained from the Pharmacy Foundation, the Egmont

Model reference adaptive vector control for induction motor without speed sensor

Directory of Open Access Journals (Sweden)

Bo Fan

2017-01-01

Full Text Available The wide applications of vector control improve the high-accuracy performance of alternating current (AC adjustable speed system. In order to obverse the full-order flux and calculate the real-time speed, this article introduces the motor T equivalent circuit to build a full-order flux observer model, where the current and flux variables of stator and rotor are adopted. Model reference adaptive control is introduced to build the AC motor flux observer. The current output is used as feedback to build the feedback matrix. The calculation method of motor speed, which is part of the inputs of flux observation, is applied to realize the adaptive control. The concept of characteristic function is introduced to calculate the flux, of which the foundation is the variables of composite form of voltage and current models. The characteristic function is deduced as a relative-state variable function. The feedback matrix is improved and designed to ensure the motor flux observer is a smooth switch between current and voltage model in low and high speeds, respectively. Experimental results show that the feedback and characteristic model are feasible, and the vector control with speed sensorless based on the full-order flux observer has better performance and anti-disturbance.

Fault Diagnosis System of Induction Motors Based on Neural Network and Genetic Algorithm Using Stator Current Signals

Directory of Open Access Journals (Sweden)

Tian Han

2006-01-01

Full Text Available This paper proposes an online fault diagnosis system for induction motors through the combination of discrete wavelet transform (DWT, feature extraction, genetic algorithm (GA, and neural network (ANN techniques. The wavelet transform improves the signal-to-noise ratio during a preprocessing. Features are extracted from motor stator current, while reducing data transfers and making online application available. GA is used to select the most significant features from the whole feature database and optimize the ANN structure parameter. Optimized ANN is trained and tested by the selected features of the measurement data of stator current. The combination of advanced techniques reduces the learning time and increases the diagnosis accuracy. The efficiency of the proposed system is demonstrated through motor faults of electrical and mechanical origins on the induction motors. The results of the test indicate that the proposed system is promising for the real-time application.

The threshold of cortical electrical stimulation for mapping sensory and motor functional areas.

Science.gov (United States)

Guojun, Zhang; Duanyu, Ni; Fu, Paul; Lixin, Cai; Tao, Yu; Wei, Du; Liang, Qiao; Zhiwei, Ren

2014-02-01

This study aimed to investigate the threshold of cortical electrical stimulation (CES) for functional brain mapping during surgery for the treatment of rolandic epilepsy. A total of 21 patients with rolandic epilepsy who underwent surgical treatment at the Beijing Institute of Functional Neurosurgery between October 2006 and March 2008 were included in this study. Their clinical data were retrospectively collected and analyzed. The thresholds of CES for motor response, sensory response, and after discharge production along with other threshold-related factors were investigated. The thresholds (mean ± standard deviation) for motor response, sensory response, and after discharge production were 3.48 ± 0.87, 3.86 ± 1.31, and 4.84 ± 1.38 mA, respectively. The threshold for after discharge production was significantly higher than those of both the motor and sensory response (both pstimulation frequency of 50 Hz and a pulse width of 0.2 ms, the threshold of sensory and motor responses were similar, and the threshold of after discharge production was higher than that of sensory and motor response. Copyright © 2013 Elsevier Ltd. All rights reserved.

De Gross Motor Function Measure (GMFM): een onderzoek naar de betrouwbaarheid van de Nederlandse vertaling.

NARCIS (Netherlands)

Veenhof, C.; Ketelaar, M.; Petegem-van Beek, E. van

2003-01-01

This article is about the psychometric characteristics of the Dutch translation of the Gross Motor Function Measure (GMFM). It describes the reliability of the instrument. The article "Gross Motor Function Measure" (GMFM): a validity study of the Dutch translation focusses on the responsiveness of

De Gross Motor Function Measure (GMFM): een onderzoek naar de responsiviteit van de Nederlandse vertaling.

NARCIS (Netherlands)

Veenhof, C.; Ketelaar, M.; Petegem-van Beek, E. van; Vermeer, A.

2003-01-01

This article is about the psychometric characteristics of the Dutch translation of the Gross Motor Function Measure (GMFM). It describes the responsiveness to change. The article "Gross Motor Function Measure (GMFM): a reliability study of the Dutch translation" focuses on the reliability of the

Generating linear regression model to predict motor functions by use of laser range finder during TUG.

Science.gov (United States)

Adachi, Daiki; Nishiguchi, Shu; Fukutani, Naoto; Hotta, Takayuki; Tashiro, Yuto; Morino, Saori; Shirooka, Hidehiko; Nozaki, Yuma; Hirata, Hinako; Yamaguchi, Moe; Yorozu, Ayanori; Takahashi, Masaki; Aoyama, Tomoki

2017-05-01

The purpose of this study was to investigate which spatial and temporal parameters of the Timed Up and Go (TUG) test are associated with motor function in elderly individuals. This study included 99 community-dwelling women aged 72.9 ± 6.3 years. Step length, step width, single support time, variability of the aforementioned parameters, gait velocity, cadence, reaction time from starting signal to first step, and minimum distance between the foot and a marker placed to 3 in front of the chair were measured using our analysis system. The 10-m walk test, five times sit-to-stand (FTSTS) test, and one-leg standing (OLS) test were used to assess motor function. Stepwise multivariate linear regression analysis was used to determine which TUG test parameters were associated with each motor function test. Finally, we calculated a predictive model for each motor function test using each regression coefficient. In stepwise linear regression analysis, step length and cadence were significantly associated with the 10-m walk test, FTSTS and OLS test. Reaction time was associated with the FTSTS test, and step width was associated with the OLS test. Each predictive model showed a strong correlation with the 10-m walk test and OLS test (P motor function test. Moreover, the TUG test time regarded as the lower extremity function and mobility has strong predictive ability in each motor function test. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Laterality of cerebral hemispheres on CT scan and gross motor function in severely handicapped children

Energy Technology Data Exchange (ETDEWEB)

Iwasaki, Nobuaki; Hamano, Kenzo; Nakamoto, Natsue; Okada, Yusuke [Tsukuba Univ., Ibaraki (Japan); Takeya, Toshiki

1997-06-01

The relation between brain damage and gross motor function in severely handicapped children (spastic type) was studied. The subjects were fifteen cases with laterality in their cerebral hemisphere CT scans (laterality group) and 28 cases with no laterality (control group). All cases were divided into four groups according to the level of gross motor function. The grade of brain damage was estimated based on CT scan analysis using the following parameters and index: maximum frontal extracerebral space (ES), maximum width of Sylvian fissure (SY), Evans` ratio, and cella media index. In the laterality group, the parameters and index were measured for both cerebral hemispheres, respectively. In the more severely disturbed hemisphere of the laterality group, ES and SY were significantly enlarged compared with those of the cases with the same level of motor function in the control group (p<0.01). In the less severely disturbed hemisphere of the laterality group, the ES, SY, Evans` ratio and cell media index were not significantly enlarged compared to cases with the same level of motor function as the control group. These findings may indicate that gross motor function of severely handicapped children is closely related to the less severely disturbed cerebral hemisphere. (author)

Laterality of cerebral hemispheres on CT scan and gross motor function in severely handicapped children

International Nuclear Information System (INIS)

Iwasaki, Nobuaki; Hamano, Kenzo; Nakamoto, Natsue; Okada, Yusuke; Takeya, Toshiki.

1997-01-01

The relation between brain damage and gross motor function in severely handicapped children (spastic type) was studied. The subjects were fifteen cases with laterality in their cerebral hemisphere CT scans (laterality group) and 28 cases with no laterality (control group). All cases were divided into four groups according to the level of gross motor function. The grade of brain damage was estimated based on CT scan analysis using the following parameters and index: maximum frontal extracerebral space (ES), maximum width of Sylvian fissure (SY), Evans' ratio, and cella media index. In the laterality group, the parameters and index were measured for both cerebral hemispheres, respectively. In the more severely disturbed hemisphere of the laterality group, ES and SY were significantly enlarged compared with those of the cases with the same level of motor function in the control group (p<0.01). In the less severely disturbed hemisphere of the laterality group, the ES, SY, Evans' ratio and cell media index were not significantly enlarged compared to cases with the same level of motor function as the control group. These findings may indicate that gross motor function of severely handicapped children is closely related to the less severely disturbed cerebral hemisphere. (author)

Frequency response function of motors for switching noise energy with a new experimental approach

International Nuclear Information System (INIS)

Kim, Hyunsu; Yoon, Jong-Yun

2017-01-01

Switching energy in electrical vehicles can create serious noise from the motors. However, the characteristics of switching noise in vehicle motors are not clear due to the complexity of measuring them. This study proposes a new experimental method to investigate the switching noise energy of a vehicle motor based on frequency response functions. A function generator-amplifier system is used to gen- erate the switching energy instead of the complex battery-inverter system that has previously been used to examine the noise energy characteristics. Even though newly adapted experimental method is simple, the switching noise energy was explicitly investigated under various input signals. Thus, this simple new method can be used to investigate the dynamic characteristics of noise energy in a vehicle motor

Frequency response function of motors for switching noise energy with a new experimental approach

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyunsu [Ensemble Center for Automotive Research, Seoul (Korea, Republic of); Yoon, Jong-Yun [Incheon National University, Incheon (Korea, Republic of)

2017-06-15

Switching energy in electrical vehicles can create serious noise from the motors. However, the characteristics of switching noise in vehicle motors are not clear due to the complexity of measuring them. This study proposes a new experimental method to investigate the switching noise energy of a vehicle motor based on frequency response functions. A function generator-amplifier system is used to gen- erate the switching energy instead of the complex battery-inverter system that has previously been used to examine the noise energy characteristics. Even though newly adapted experimental method is simple, the switching noise energy was explicitly investigated under various input signals. Thus, this simple new method can be used to investigate the dynamic characteristics of noise energy in a vehicle motor.

Effect of α{sub 7} nicotinic acetylcholine receptor agonists and antagonists on motor function in mice

Energy Technology Data Exchange (ETDEWEB)

Welch, Kevin D., E-mail: kevin.welch@ars.usda.gov [USDA/ARS Poisonous Plant Research Laboratory, 1150 E. 1400N., Logan, UT 84341 (United States); Pfister, James A. [USDA/ARS Poisonous Plant Research Laboratory, 1150 E. 1400N., Logan, UT 84341 (United States); Lima, Flavia G. [Federal University of Goías, School of Veterinary Medicine, Goiânia, Goías (Brazil); Green, Benedict T.; Gardner, Dale R. [USDA/ARS Poisonous Plant Research Laboratory, 1150 E. 1400N., Logan, UT 84341 (United States)

2013-02-01

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated cation channels found throughout the body, and serve to mediate diverse physiological functions. Muscle-type nAChRs located in the motor endplate region of muscle fibers play an integral role in muscle contraction and thus motor function. The toxicity and teratogenicity of many plants (which results in millions of dollars in losses annually to the livestock industry) are due to various toxins that bind to nAChRs including deltaline and methyllycaconitine (MLA) from larkspur (Delphinium) species, and nicotine and anabasine from tobacco (Nicotiana) species. The primary result of the actions of these alkaloids at nAChRs is neuromuscular paralysis and respiratory failure. The objective of this study was to further characterize the motor coordination deficiencies that occur upon exposure to a non-lethal dose of nAChR antagonists MLA and deltaline as well as nAChR agonists nicotine and anabasine. We evaluated the effect of nAChR agonists and antagonists on the motor function and coordination in mice using a balance beam, grip strength meter, rotarod, open field analysis and tremor monitor. These analyses demonstrated that within seconds after treatment the mice had significant loss of motor function and coordination that lasted up to 1 min, followed by a short period of quiescence. Recovery to normal muscle coordination was rapid, typically within approximately 10 min post-dosing. However, mice treated with the nAChR agonist nicotine and anabasine required a slightly longer time to recover some aspects of normal muscle function in comparison to mice treated with the nAChR antagonist MLA or deltaline. -- Highlights: ► Mice treated with nAChR agonists and antagonists have a loss in motor function. ► These deficits are temporary as near normal motor function returns within 10 min. ► There are compound-specific differences in the effects on motor function.

Three-dimensional visualization of functional brain tissue and functional magnetic resonance imaging-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex

International Nuclear Information System (INIS)

Han Tong; Cui Shimin; Tong Xiaoguang; Liu Li; Xue Kai; Liu Meili; Liang Siquan; Zhang Yunting; Zhi Dashi

2011-01-01

Objective: To assess the value of three -dimensional visualization of functional brain tissue and the functional magnetic resonance imaging (fMRI)-integrated neuronavigation in the resection of brain tumor adjacent to motor cortex. Method: Sixty patients with tumor located in the central sulcus were enrolled. Thirty patients were randomly assigned to function group and 30 to control group. Patients in function group underwent fMRI to localize the functional brain tissues. Then the function information was transferred to the neurosurgical navigator. The patients in control group underwent surgery with navigation without function information. The therapeutic effect, excision rate. improvement of motor function, and survival quality during follow-up were analyzed. Result: All patients in function group were accomplished visualization of functional brain tissues and fMRI-integrated neuronavigation. The locations of tumors, central sulcus and motor cortex were marked during the operation. The fMRI -integrated information played a great role in both pre- and post-operation. Pre-operation: designing the location of the skin flap and window bone, determining the relationship between the tumor and motor cortex, and designing the pathway for the resection. Post- operation: real-time navigation of relationship between the tumor and motor cortex, assisting to localize the motor cortex using interoperation ultra-sound for correcting the displacement by the CSF outflow and collapsing tumor. The patients in the function group had better results than the patients in the control group in therapeutic effect (u=2.646, P=0.008), excision rate (χ = 7.200, P<0.01), improvement of motor function (u=2.231, P=0.026), and survival quality (KPS u c = 2.664, P=0.008; Zubrod -ECOG -WHO u c =2.135, P=0.033). Conclusions: Using preoperative three -dimensional visualization of cerebral function tissue and the fMRI-integrated neuronavigation technology, combining intraoperative accurate

State of motor function of stomach in patients with cervix uteri carcinoma in combined radiotherapy

International Nuclear Information System (INIS)

Zhidovtseva, M.I.; Shutilova, A.A.; Dynnik, M.S.; Lugovskaya, K.A.; Duma, V.A.

1978-01-01

Data on studying stomach motor function in patients with carvix uteri carcinoma of 2 and 3 stages in combined radiotherapy are given. The patients were examined before radiotherapy and directly after it as well as in 1-2 years using the X-ray method for 50 patients and electrogastrography for 68 patients. Revealed changes in stomach motor function, being considered as a response to irradiation, were manifested more often in decreasing motility, evacuatory function and bioelectric stomach activity. These functional changes result in disturbance of general state of patients, appearance of symptomatology of stomach dysfunction and serve as indications for the prescription of correcting therapy, which includes diet and preparations strengthening stomach motor activity

Effect of hippotherapy on gross motor function in children with cerebral palsy: a randomized controlled trial.

Science.gov (United States)

Kwon, Jeong-Yi; Chang, Hyun Jung; Yi, Sook-Hee; Lee, Ji Young; Shin, Hye-Yeon; Kim, Yun-Hee

2015-01-01

To examine whether hippotherapy has a clinically significant effect on gross motor function in children with cerebral palsy (CP). Randomized controlled trial. Outpatient therapy center. Ninety-two children with CP, aged 4-10 years, presenting variable function (Gross Motor Function Classification System [GMFCS] levels I-IV). Hippotherapy (30 minutes twice weekly for 8 consecutive weeks). Gross Motor Function Measure (GMFM)-88, GMFM-66, and Pediatric Balance Scale. Pre- and post-treatment measures were completed by 91 children (45 in the intervention group and 46 in the control group). Differences in improvement on all three measures significantly differed between groups after the 8-week study period. Dimensions of GMFM-88 improved significantly after hippotherapy varied by GMFCS level: dimension E in level I, dimensions D and E in level II, dimensions C and D in level III, and dimensions B and C in level IV. Hippotherapy positively affects gross motor function and balance in children with CP of various functional levels.

Higher Efficiency HVAC Motors

Energy Technology Data Exchange (ETDEWEB)

Flynn, Charles Joseph [QM Power, Inc., Kansas City, MO (United States)

2018-02-13

The objective of this project was to design and build a cost competitive, more efficient heating, ventilation, and air conditioning (HVAC) motor than what is currently available on the market. Though different potential motor architectures among QMP’s primary technology platforms were investigated and evaluated, including through the building of numerous prototypes, the project ultimately focused on scaling up QM Power, Inc.’s (QMP) Q-Sync permanent magnet synchronous motors from available sub-fractional horsepower (HP) sizes for commercial refrigeration fan applications to larger fractional horsepower sizes appropriate for HVAC applications, and to add multi-speed functionality. The more specific goal became the research, design, development, and testing of a prototype 1/2 HP Q-Sync motor that has at least two operating speeds and 87% peak efficiency compared to incumbent electronically commutated motors (EC or ECM, also known as brushless direct current (DC) motors), the heretofore highest efficiency HVACR fan motor solution, at approximately 82% peak efficiency. The resulting motor prototype built achieved these goals, hitting 90% efficiency and .95 power factor at full load and speed, and 80% efficiency and .7 power factor at half speed. Q-Sync, developed in part through a DOE SBIR grant (Award # DE-SC0006311), is a novel, patented motor technology that improves on electronically commutated permanent magnet motors through an advanced electronic circuit technology. It allows a motor to “sync” with the alternating current (AC) power flow. It does so by eliminating the constant, wasteful power conversions from AC to DC and back to AC through the synthetic creation of a new AC wave on the primary circuit board (PCB) by a process called pulse width modulation (PWM; aka electronic commutation) that is incessantly required to sustain motor operation in an EC permanent magnet motor. The Q-Sync circuit improves the power factor of the motor by removing all

Gross motor function in children with spastic Cerebral Palsy and Cerebral Visual Impairment : A comparison between outcomes of the original and the Cerebral Visual Impairment adapted Gross Motor Function Measure-88 (GMFM-88-CVI)

NARCIS (Netherlands)

Salavati, M.; Rameckers, E. A. A.; Waninge, A.; Krijnen, W. P.; Steenbergen, B.; van der Schans, C. P.

Purpose: To investigate whether the adapted version of the Gross Motor Function Measure 88 (GMFM-88) for children with Cerebral Palsy (CP) and Cerebral Visual Impairment (CVI) results in higher scores. This is most likely to be a reflection of their gross motor function, however it may be the result

An experimental evaluation of a new designed apparatus (NDA) for the rapid measurement of impaired motor function in rats.

Science.gov (United States)

Jarrahi, M; Sedighi Moghadam, B; Torkmandi, H

2015-08-15

Assessment of the ability of rat to balance by rotarod apparatus (ROTA) is frequently used as a measure of impaired motor system function. Most of these methods have some disadvantages, such as failing to sense motor coordination rather than endurance and as the sensitivity of the method is low, more animals are needed to obtain statistically significant results. We have designed and tested a new designed apparatus (NDA) to measure motor system function in rats. Our system consists of a glass box containing 4 beams which placed with 1cm distance between them, two electrical motors for rotating the beams, and a camera to record the movements of the rats. The RPM of the beams is adjustable digitally between 0 and 50 rounds per minute. We evaluated experimentally the capability of the NDA for the rapid measurement of impaired motor function in rats. Also we demonstrated that the sensitivity of the NDA increases by faster rotation speeds and may be more sensitive than ROTA for evaluating of impaired motor system function. Compared to a previous version of this task, our NDA provides a more efficient method to test rodents for studies of motor system function after impaired motor nervous system. In summary, our NDA will allow high efficient monitoring of rat motor system function and may be more sensitive than ROTA for evaluating of impaired motor system function in rats. Copyright © 2015 Elsevier B.V. All rights reserved.

A Strategy for Embedding Functional Motor and Early Numeracy Skill Instruction into Physical Education Activities

Science.gov (United States)

Whinnery, Stacie B.; Whinnery, Keith W.; Eddins, Daisy

2016-01-01

This article addresses the challenges educators face when attempting to find a balance between both functional and academic skill instruction for students with severe, multiple disabilities including motor impairments. The authors describe a strategy that employs embedded instruction of early numeracy and functional motor skills during physical…

Detection of mechanical failures in induction motors by current spectrum analysis

Energy Technology Data Exchange (ETDEWEB)

Sokansky, K; Novak, P; Bilos, J; Labaj, J [Technical University Ostrava, Moraviasilesian Power Stations s.h.c. (Czech Republic)

1998-12-31

From the diagnostic point of view, an electric machine can be understood as an electromechanical system. It means that any manifestations of mechanical failures do not have to show themselves only in mechanical quantities, i.e. vibration in our case. Mechanical failures can also manifest themselves in electrical quantities, namely in electric current in our case. This statement is valid inversely too, which means that faults occurring in electric circuits can be measured through mechanical quantities. This presentation deals with measuring the current spectra of induction motors with short circuited armatures that are drives used in the industries most. (orig.) 3 refs.

Detection of mechanical failures in induction motors by current spectrum analysis

Energy Technology Data Exchange (ETDEWEB)

Sokansky, K.; Novak, P.; Bilos, J.; Labaj, J. [Technical University Ostrava, Moraviasilesian Power Stations s.h.c. (Czech Republic)

1997-12-31

From the diagnostic point of view, an electric machine can be understood as an electromechanical system. It means that any manifestations of mechanical failures do not have to show themselves only in mechanical quantities, i.e. vibration in our case. Mechanical failures can also manifest themselves in electrical quantities, namely in electric current in our case. This statement is valid inversely too, which means that faults occurring in electric circuits can be measured through mechanical quantities. This presentation deals with measuring the current spectra of induction motors with short circuited armatures that are drives used in the industries most. (orig.) 3 refs.

3-D analysis of eddy current in permanent magnet of interior permanent magnet motors

International Nuclear Information System (INIS)

Kawase, Yoshihiro; Yamaguchi, Tadashi; Fukanaga, Hiromu; Ito, Shokichi

2002-01-01

Interior permanent magnet motors are widely used in various fields. However, in high-speed operations, it is important to decrease the eddy current loss in the permanent magnet. In order to decrease the eddy current loss, we propose to divide the permanent magnet. In this paper, we clarified the effect of division of permanent magnet on the eddy current loss using the 3-D finite element method. (Author)

Functional BOLD MRI: comparison of different field strengths in a motor task

International Nuclear Information System (INIS)

Meindl, T.; Born, C.; Britsch, S.; Reiser, M.; Schoenberg, S.

2008-01-01

The purpose was to evaluate the benefit of an increased field strength for functional magnetic resonance imaging in a motor task. Six right-handed volunteers were scanned at 1.5 T and 3.0 T using a motor task. Each experiment consisted of two runs with four activation blocks, each with right- and left-hand tapping. Analysis was done using BrainVoyagerQX registered . Differences between both field strengths concerning signal to noise (SNR), blood oxygen level-dependent (BOLD) signal change, functional sensitivity and BOLD contrast to noise (CNR) were tested using a paired t test. Delineation of activations and artifacts were graded by two independent readers. Results were further validated by means of a phantom study. The sensorimotor and premotor cortex, the supplementary motor area, subcortical and cerebellar structures were activated at each field strength. Additional activations of the right premotor cortex and right superior temporal gyrus were found at 3.0 T. Signal-to-noise, percentage of BOLD signal change, BOLD CNR and functional sensitivity improved at 3.0 T by a factor of up to 2.4. Functional imaging at 3.0 T results in detection of additional activated areas, increased SNR, BOLD signal change, functional sensitivity and BOLD CNR. (orig.)

Functional Communication Profiles in Children with Cerebral Palsy in Relation to Gross Motor Function and Manual and Intellectual Ability.

Science.gov (United States)

Choi, Ja Young; Park, Jieun; Choi, Yoon Seong; Goh, Yu Ra; Park, Eun Sook

2018-07-01

The aim of the present study was to investigate communication function using classification systems and its association with other functional profiles, including gross motor function, manual ability, intellectual functioning, and brain magnetic resonance imaging (MRI) characteristics in children with cerebral palsy (CP). This study recruited 117 individuals with CP aged from 4 to 16 years. The Communication Function Classification System (CFCS), Viking Speech Scale (VSS), Speech Language Profile Groups (SLPG), Gross Motor Function Classification System (GMFCS), Manual Ability Classification System (MACS), and intellectual functioning were assessed in the children along with brain MRI categorization. Very strong relationships were noted among the VSS, CFCS, and SLPG, although these three communication systems provide complementary information, especially for children with mid-range communication impairment. These three communication classification systems were strongly related with the MACS, but moderately related with the GMFCS. Multiple logistic regression analysis indicated that manual ability and intellectual functioning were significantly related with VSS and CFCS function, whereas only intellectual functioning was significantly related with SLPG functioning in children with CP. Communication function in children with a periventricular white matter lesion (PVWL) varied widely. In the cases with a PVWL, poor functioning was more common on the SLPG, compared to the VSS and CFCS. Very strong relationships were noted among three communication classification systems that are closely related with intellectual ability. Compared to gross motor function, manual ability seemed more closely related with communication function in these children. © Copyright: Yonsei University College of Medicine 2018.

Dynamic eccentricity fault diagnosis in round rotor synchronous motors

International Nuclear Information System (INIS)

Ebrahimi, Bashir Mahdi; Etemadrezaei, Mohammad; Faiz, Jawad

2011-01-01

Research highlights: → We have presented a novel approach to detect dynamic eccentricity in round rotor synchronous motors. → We have introduced an efficient index based on processing torque using time series data mining method. → The stator current spectrum of the motor under different levels of fault and load are computed. → Winding function method has been employed to model healthy and faulty synchronous motors. -- Abstract: In this paper, a novel approach is presented to detect dynamic eccentricity in round rotor synchronous motors. For this, an efficient index is introduced based on processing developed torque using time series data mining (TSDM) method. This index can be utilized to diagnose eccentricity fault and its degree. The capability of this index to predict dynamic eccentricity is illustrated by investigation of load variation impacts on the nominated index. Stator current spectrum of the faulty synchronous motor under different loads and dynamic eccentricity degrees are computed. Effects of the dynamic eccentricity and load variation simultaneously are scrutinized on the magnitude of 17th and 19th harmonic components as traditional indices for eccentricity fault diagnosis in synchronous motors. Necessity signals and parameters for processing and feature extraction are evaluated by winding function method which is employed to model healthy and faulty synchronous motors.

Viral and cellular SOS-regulated motor proteins: dsDNA translocation mechanisms with divergent functions.

Science.gov (United States)

Wolfe, Annie; Phipps, Kara; Weitao, Tao

2014-01-01

DNA damage attacks on bacterial cells have been known to activate the SOS response, a transcriptional response affecting chromosome replication, DNA recombination and repair, cell division and prophage induction. All these functions require double-stranded (ds) DNA translocation by ASCE hexameric motors. This review seeks to delineate the structural and functional characteristics of the SOS response and the SOS-regulated DNA translocases FtsK and RuvB with the phi29 bacteriophage packaging motor gp16 ATPase as a prototype to study bacterial motors. While gp16 ATPase, cellular FtsK and RuvB are similarly comprised of hexameric rings encircling dsDNA and functioning as ATP-driven DNA translocases, they utilize different mechanisms to accomplish separate functions, suggesting a convergent evolution of these motors. The gp16 ATPase and FtsK use a novel revolution mechanism, generating a power stroke between subunits through an entropy-DNA affinity switch and pushing dsDNA inward without rotation of DNA and the motor, whereas RuvB seems to employ a rotation mechanism that remains to be further characterized. While FtsK and RuvB perform essential tasks during the SOS response, their roles may be far more significant as SOS response is involved in antibiotic-inducible bacterial vesiculation and biofilm formation as well as the perspective of the bacteria-cancer evolutionary interaction.

Broken-Rotor-Bar Diagnosis for Induction Motors

International Nuclear Information System (INIS)

Wang Jinjiang; Gao, Robert X; Yan Ruqiang

2011-01-01

Broken rotor bar is one of the commonly encountered induction motor faults that may cause serious motor damage to the motor if not detected timely. Past efforts on broken rotor bar diagnosis have been focused on current signature analysis using spectral analysis and wavelet transform. These methods require accurate slip estimation to localize fault-related frequency. This paper presents a new approach to broken rotor bar diagnosis without slip estimation, based on the ensemble empirical mode decomposition (EEMD) and the Hilbert transform. Specifically, the Hilbert transform first extracts the envelope of the motor current signal, which contains broken rotor fault-related frequency information. Subsequently, the envelope signal is adaptively decomposed into a number of intrinsic mode functions (IMFs) by the EEMD algorithm. Two criteria based on the energy and correlation analyses have been investigated to automate the IMF selection. Numerical and experimental studies have confirmed that the proposed approach is effective in diagnosing broken rotor bar faults for improved induction motor condition monitoring and damage assessment.

Functional MRI of tongue motor tasks in patients with tongue cancer: observations before and after partial glossectomy

International Nuclear Information System (INIS)

Haupage, Samantha; Branski, Ryan C.; Kraus, Dennis; Peck, Kyung K.; Hsu, Meier; Holodny, Andrei

2010-01-01

The current study seeks to provide preliminary data regarding this central, adaptive response during tongue motor tasks utilizing functional magnetic resonance imaging (fMRI) before and after glossectomy. Six patients, with confirmed histological diagnoses of oral tongue cancer, underwent fMRI before and 6 months after partial glossectomy. These data were compared to nine healthy controls. All subjects performed three tongue motor tasks during fMRI: tongue tapping (TT), dry swallow (Dry), and wet swallow (Wet). Following surgery, increased activation was subjectively observed in the superior parietal lobule, supplementary motor area, and anterior cingulate. Region of interest (ROI) analysis of the precentral gyrus confirmed increased cortical activity following surgery. In addition, comparisons between pre-surgical scans and controls suggested the dry swallow task was sensitive to elicit tongue-related activation in the precentral gyrus (p ≤ 0.05). The adaptive changes in the cortex following partial glossectomy reflect recruitment of the parietal, frontal, and cingulate cortex during tongue motor tasks. In addition, post-operative activation patterns more closely approximated control levels than the pre-operative scans. Furthermore, the dry swallow task appears most specific to elicit tongue-related cortical activity. (orig.)

Functional MRI of tongue motor tasks in patients with tongue cancer: observations before and after partial glossectomy

Energy Technology Data Exchange (ETDEWEB)

Haupage, Samantha; Branski, Ryan C.; Kraus, Dennis [Memorial Sloan-Kettering Cancer Center, Head and Neck Surgery, New York, NY (United States); Peck, Kyung K. [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States); Memorial Sloan-Kettering Cancer Center, Medical Physics, New York, NY (United States); Memorial Sloan-Kettering Cancer Center, Department of Medical Physics and Radiology, New York, NY (United States); Hsu, Meier [Memorial Sloan-Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Holodny, Andrei [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States)

2010-12-15

The current study seeks to provide preliminary data regarding this central, adaptive response during tongue motor tasks utilizing functional magnetic resonance imaging (fMRI) before and after glossectomy. Six patients, with confirmed histological diagnoses of oral tongue cancer, underwent fMRI before and 6 months after partial glossectomy. These data were compared to nine healthy controls. All subjects performed three tongue motor tasks during fMRI: tongue tapping (TT), dry swallow (Dry), and wet swallow (Wet). Following surgery, increased activation was subjectively observed in the superior parietal lobule, supplementary motor area, and anterior cingulate. Region of interest (ROI) analysis of the precentral gyrus confirmed increased cortical activity following surgery. In addition, comparisons between pre-surgical scans and controls suggested the dry swallow task was sensitive to elicit tongue-related activation in the precentral gyrus (p {<=} 0.05). The adaptive changes in the cortex following partial glossectomy reflect recruitment of the parietal, frontal, and cingulate cortex during tongue motor tasks. In addition, post-operative activation patterns more closely approximated control levels than the pre-operative scans. Furthermore, the dry swallow task appears most specific to elicit tongue-related cortical activity. (orig.)

Correlation between movement of the feet and motor function of children with chronic encephalopathy

Directory of Open Access Journals (Sweden)

Táubuta Gomes Souza

Full Text Available Abstract Introduction: Chronic non-progressive encephalopathy (CNPE is one of the most common causes of physical deformities in childhood. It is characterized by non-progressive neuropathological abnormalities of the developing brain, which results in neuromotor impairments and changes in posture and movement. Objective: To evaluate foot deformities in children with CNPE, by measuring the joint amplitude and correlating these measures with the scores of the Gross Motor Function Measure (GMFM-88, using all its five dimensions. Methods: Cross-sectional and descriptive study with a sample of 17 children. The data collection instruments used were manual goniometer and the Gross Motor Function Measure test (GMFM-88. Data were analyzed using the program SPSS version 18, and the Pearson correlation test as a measure of association. Results: Children with chronic encephalopathy and a reduced amplitude motion have lower capacity in motor function. Statistically significant correlation was found for the right dorsiflexion angle (p = 0.023, left dorsiflexion angle (p = 0.019, right inversion (p = 0.040, left inversion (p = 0.034 and left eversion (p = 0.018. There was no statistically significant correlation for the right eversion (p > 0.05. Conclusion: Musculoskeletal disorders associated with CNPE and foot deformities interfere negatively in motor function, compromising the functional performance of these children.

Fine Motor Function Skills in Patients with Parkinson Disease with and without Mild Cognitive Impairment.

Science.gov (United States)

Dahdal, Philippe; Meyer, Antonia; Chaturvedi, Menorca; Nowak, Karolina; Roesch, Anne D; Fuhr, Peter; Gschwandtner, Ute

2016-01-01

The objective of this study was to investigate the relation between impaired fine motor skills in Parkinson disease (PD) patients and their cognitive status, and to determine whether fine motor skills are more impaired in PD patients with mild cognitive impairment (MCI) than in non-MCI patients. Twenty PD MCI and 31 PD non-MCI patients (mean age 66.7 years, range 50-84, 36 males/15 females), all right-handed, took part in a motor performance test battery. Steadiness, precision, dexterity, velocity of arm-hand movements, and velocity of wrist-finger movements were measured and compared across groups and analyzed for confounders (age, sex, education, severity of motor symptoms, and disease duration). Statistical analysis included t tests corrected for multiple testing, and a linear regression with stepwise elimination procedure was used to select significant predictors for fine motor function. PD MCI patients performed significantly worse in precision (p motor function skills were confounded by age. Fine motor skills in PD MCI patients are impaired compared to PD non-MCI patients. Investigating the relation between the fine motor performance and MCI in PD might be a relevant subject for future research. © 2016 S. Karger AG, Basel.

Toward a more personalized motor function rehabilitation in Myotonic dystrophy type 1: The role of neuroplasticity.

Directory of Open Access Journals (Sweden)

Simona Portaro

Full Text Available Myotonic dystrophy type 1 (DM1 is the most prevalent adult muscular dystrophy, often accompanied by impairments in attention, memory, visuospatial and executive functions. Given that DM1 is a multi-system disorder, it requires a multi-disciplinary approach, including effective rehabilitation programs, focusing on the central nervous system neuroplasticity, in order to develop patient-tailored rehabilitative procedures for motor function recovery. Herein, we performed a transcranial magnetic stimulation (TMS study aimed at investigating central motor conduction time, sensory-motor plasticity, and cortical excitability in 7 genetically defined DM1 patients. As compared to healthy individuals, DM1 patients showed a delayed central motor conduction time and an abnormal sensory-motor plasticity, with no alteration of cortical excitability. These findings may be useful to define patient-tailored motor rehabilitative programs.

Gross Motor Function Measure Evolution Ratio: Use as a Control for Natural Progression in Cerebral Palsy.

Science.gov (United States)

Marois, Pierre; Marois, Mikael; Pouliot-Laforte, Annie; Vanasse, Michel; Lambert, Jean; Ballaz, Laurent

2016-05-01

To develop a new way to interpret Gross Motor Function Measure (GMFM-66) score improvement in studies conducted without control groups in children with cerebral palsy (CP). The curves, which describe the pattern of motor development according to the children's Gross Motor Function Classification System level, were used as historical control to define the GMFM-66 expected natural evolution in children with CP. These curves have been modeled and generalized to fit the curve to particular children characteristics. Research center. Not applicable. Not applicable. Not applicable. Assuming that the GMFM-66 score evolution followed the shape of the Rosenbaum curves, by taking into account the age and GMFM-66 score of children, the expected natural evolution of the GMFM-66 score was predicted for any group of children with CP who were Ratio, was defined as follows: Gross Motor Function Measure Evolution Ratio=measured GMFM-66 score change/expected natural evolution. For practical or ethical reasons, it is almost impossible to use control groups in studies evaluating effectiveness of many therapeutic modalities. The Gross Motor Function Measure Evolution Ratio gives the opportunity to take into account the expected natural evolution of the gross motor function of children with CP, which is essential to accurately interpret the therapy effect on the GMFM-66. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

46 CFR 169.684 - Overcurrent protection for motors and motor branch circuits.

Science.gov (United States)

2010-10-01

...) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations Operating at... motor that is responsive to motor current or to both motor current and temperature may be used. (b) The...

Transcranial direct current stimulation (tDCS) Paired with massed practice training to promote adaptive plasticity and motor recovery in chronic incomplete tetraplegia: a pilot study.

Science.gov (United States)

Potter-Baker, Kelsey A; Janini, Daniel P; Lin, Yin-Liang; Sankarasubramanian, Vishwanath; Cunningham, David A; Varnerin, Nicole M; Chabra, Patrick; Kilgore, Kevin L; Richmond, Mary Ann; Frost, Frederick S; Plow, Ela B

2017-08-07

Objective Our goal was to determine if pairing transcranial direct current stimulation (tDCS) with rehabilitation for two weeks could augment adaptive plasticity offered by these residual pathways to elicit longer-lasting improvements in motor function in incomplete spinal cord injury (iSCI). Design Longitudinal, randomized, controlled, double-blinded cohort study. Setting Cleveland Clinic Foundation, Cleveland, Ohio, USA. Participants Eight male subjects with chronic incomplete motor tetraplegia. Interventions Massed practice (MP) training with or without tDCS for 2 hrs, 5 times a week. Outcome Measures We assessed neurophysiologic and functional outcomes before, after and three months following intervention. Neurophysiologic measures were collected with transcranial magnetic stimulation (TMS). TMS measures included excitability, representational volume, area and distribution of a weaker and stronger muscle motor map. Functional assessments included a manual muscle test (MMT), upper extremity motor score (UEMS), action research arm test (ARAT) and nine hole peg test (NHPT). Results We observed that subjects receiving training paired with tDCS had more increased strength of weak proximal (15% vs 10%), wrist (22% vs 10%) and hand (39% vs. 16%) muscles immediately and three months after intervention compared to the sham group. Our observed changes in muscle strength were related to decreases in strong muscle map volume (r=0.851), reduced weak muscle excitability (r=0.808), a more focused weak muscle motor map (r=0.675) and movement of weak muscle motor map (r=0.935). Conclusion Overall, our results encourage the establishment of larger clinical trials to confirm the potential benefit of pairing tDCS with training to improve the effectiveness of rehabilitation interventions for individuals with SCI. Trial Registration NCT01539109.

Fault Diagnosis of Three Phase Induction Motor Using Current Signal, MSAF-Ratio15 and Selected Classifiers

Directory of Open Access Journals (Sweden)

Glowacz A.

2017-12-01

Full Text Available A degradation of metallurgical equipment is normal process depended on time. Some factors such as: operation process, friction, high temperature can accelerate the degradation process of metallurgical equipment. In this paper the authors analyzed three phase induction motors. These motors are common used in the metallurgy industry, for example in conveyor belt. The diagnostics of such motors is essential. An early detection of faults prevents financial loss and downtimes. The authors proposed a technique of fault diagnosis based on recognition of currents. The authors analyzed 4 states of three phase induction motor: healthy three phase induction motor, three phase induction motor with 1 faulty rotor bar, three phase induction motor with 2 faulty rotor bars, three phase induction motor with faulty ring of squirrel-cage. An analysis was carried out for original method of feature extraction called MSAF-RATIO15 (Method of Selection of Amplitudes of Frequencies – Ratio 15% of maximum of amplitude. A classification of feature vectors was performed by Bayes classifier, Linear Discriminant Analysis (LDA and Nearest Neighbour classifier. The proposed technique of fault diagnosis can be used for protection of three phase induction motors and other rotating electrical machines. In the near future the authors will analyze other motors and faults. There is also idea to use thermal, acoustic, electrical, vibration signal together.

Muscle Hyperalgesia Correlates With Motor Function in Complex Regional Pain Syndrome Type 1

NARCIS (Netherlands)

van Rooijen, Diana E.; Marinus, Johan; Schouten, Alfred Christiaan; Noldus, Lucas P.J.J.; van Hilten, Jacobus J.

2013-01-01

At present it is unclear if disturbed sensory processing plays a role in the development of the commonly observed motor impairments in patients with complex regional pain syndrome (CRPS). This study aims to investigate the relation between sensory and motor functioning in CRPS patients with and

Genetic and environmental influences on motor function: a magnetoencephalographic study of twins

Directory of Open Access Journals (Sweden)

Toshihiko eAraki

2014-06-01

Full Text Available To investigate the effect of genetic and environmental influences on cerebral motor function, we determined similarities of movement-related cortical fields (MRCFs in middle-aged and elderly monozygotic (MZ twins. MRCFs were measured using a 160-channel MEG system when MZ twins were instructed to repeat lifting of the right index finger. We compared latency, amplitude, dipole location, and dipole intensity of movement-evoked field 1 (MEF1 between 16 MZ twins and 16 pairs of genetically unrelated pairs. Differences in latency and dipole location between MZ twins were significantly less than those between unrelated age-matched pairs. However, amplitude and dipole intensity were not significantly different. These results suggest that the latency and dipole location of MEF1 are determined early in life by genetic and early common environmental factors, whereas amplitude and dipole intensity are influenced by long-term environmental factors. Improved understanding of genetic and environmental factors that influence cerebral motor function may contribute to evaluation and improvement for individual motor function.

Aging-associated changes in motor axon voltage-gated Na+ channel function in mice

DEFF Research Database (Denmark)

Moldovan, Mihai; Rosberg, Mette Romer; Alvarez Herrero, Susana

2016-01-01

the functional impairment. The aim of the present study was to investigate the effect of regular aging on motor axon function with particular emphasis on Nav1.8. We compared tibial nerve conduction and excitability measures by threshold tracking in 12 months (mature) and 20 months (aged) wild-type (WT) mice...... expression was found by immunohistochemistry. The depolarizing excitability features were absent in Nav1.8 null mice, and they were counteracted in WT mice by a Nav1.8 blocker. Our data suggest that alteration in voltage-gated Na+ channel isoform expression contributes to changes in motor axon function...

Analysis of the Torque Ripples in Designing a Disk Type Brushless Direct Current Motor

Directory of Open Access Journals (Sweden)

A. V. Stepanov

2015-01-01

Full Text Available This paper investigates the torque ripples of disk-type low-power brushless direct current motor (BDCM with permanent magnets. In spite of numerous studies on designing of valve engines this issue is understudied as yet. The torque ripples cause noise and vibration and can significantly limit accuracy when used in instrumentation, computer technology.We consider a motor that includes a power unit consisting of a rotor and a stator. There are ferrite elements of sensor on the rotor, and the nonmagnetic disk, bonded to it, contains permanent magnets. The rotor is mounted on a rotating shaft. The stator consists of a steel casing and bonded to it non-magnetic, non-conductive disk with holes. In the disk holes from both sides are mounted armature coils. The armature winding consists of two sections each of which has 6 coils. Each adjacent coil in section has an opposite direction of winding. The coils are arranged circumferentially and are shifted relative to each other; the displacement angle between the coils of one section is equal to 2π/6 (rad. Sections are also shifted relative to each other; the angular shift is π/6 (rad. Sections are connected to the output terminals of the electronic switch. Sections of motor windings have the reverse full-wave power.The paper has investigated the steady operation at four-stroke switching and under constant load (torque. In this case, the electromagnetic torque and rotor speed are periodical functions of the rotor rotation angle. The dependencies of the averaged torque on the rotation speed have been obtained. The spectral distribution of the torque ripples at various rotor speeds of rotation has been calculated. The dependencies of the torque on the speed were studied both at constant speed and taking into account the uneven speed. Based on the research findings of disk type BDCM was computed a level of ripples amounted to 0.8 - 5%, which is quite acceptable for use in a drive. The results are useful for

Effect of age on changes in motor units functional connectivity.

Science.gov (United States)

Arjunan, Sridhar P; Kumar, Dinesh

2015-08-01

With age, there is a change in functional connectivity of motor units in muscle. This leads to reduced muscle strength. This study has investigated the effect of age on the changes in the motor unit recruitment by measuring the mutual information between multiple channels of surface electromyogram (sEMG) of biceps brachii muscle. It is hypothesised that with ageing, there is a reduction in number of motor units, which can lead to an increase in the dependency of remaining motor units. This increase can be observed in the mutual information between the multiple channels of the muscle activity. Two channels of sEMG were recorded during the maximum level of isometric contraction. 28 healthy subjects (Young: age range 20-35years and Old: age range - 60-70years) participated in the experiments. The normalized mutual information (NMI), a measure of dependency factor, was computed for the sEMG recordings. Statistical analysis was performed to test the effect of age on NMI. The results show that the NMI among the older cohort was significantly higher when compared with the young adults.

Esophageal hypomotility and spastic motor disorders: current diagnosis and treatment.

Science.gov (United States)

Valdovinos, Miguel A; Zavala-Solares, Monica R; Coss-Adame, Enrique

2014-11-01

Esophageal hypomotility (EH) is characterized by abnormal esophageal peristalsis, either from a reduction or absence of contractions, whereas spastic motor disorders (SMD) are characterized by an increase in the vigor and/or propagation velocity of esophageal body contractions. Their pathophysiology is not clearly known. The reduced excitation of the smooth muscle contraction mediated by cholinergic neurons and the impairment of inhibitory ganglion neuronal function mediated by nitric oxide are likely mechanisms of the peristaltic abnormalities seen in EH and SMD, respectively. Dysphagia and chest pain are the most frequent clinical manifestations for both of these dysfunctions, and gastroesophageal reflux disease (GERD) is commonly associated with these motor disorders. The introduction of high-resolution manometry (HRM) and esophageal pressure topography (EPT) has significantly enhanced the ability to diagnose EH and SMD. Novel EPT metrics in particular the development of the Chicago Classification of esophageal motor disorders has enabled improved characterization of these abnormalities. The first step in the management of EH and SMD is to treat GERD, especially when esophageal testing shows pathologic reflux. Smooth muscle relaxants (nitrates, calcium channel blockers, 5-phosphodiesterase inhibitors) and pain modulators may be useful in the management of dysphagia or pain in SMD. Endoscopic Botox injection and pneumatic dilation are the second-line therapies. Extended myotomy of the esophageal body or peroral endoscopic myotomy (POEM) may be considered in highly selected cases but lack evidence.

Is Rest Really Rest? Resting State Functional Connectivity during Rest and Motor Task Paradigms.

Science.gov (United States)

Jurkiewicz, Michael T; Crawley, Adrian P; Mikulis, David J

2018-04-18

Numerous studies have identified the default mode network (DMN) within the brain of healthy individuals, which has been attributed to the ongoing mental activity of the brain during the wakeful resting-state. While engaged during specific resting-state fMRI paradigms, it remains unclear as to whether traditional block-design simple movement fMRI experiments significantly influence the default mode network or other areas. Using blood-oxygen level dependent (BOLD) fMRI we characterized the pattern of functional connectivity in healthy subjects during a resting-state paradigm and compared this to the same resting-state analysis performed on motor task data residual time courses after regressing out the task paradigm. Using seed-voxel analysis to define the DMN, the executive control network (ECN), and sensorimotor, auditory and visual networks, the resting-state analysis of the residual time courses demonstrated reduced functional connectivity in the motor network and reduced connectivity between the insula and the ECN compared to the standard resting-state datasets. Overall, performance of simple self-directed motor tasks does little to change the resting-state functional connectivity across the brain, especially in non-motor areas. This would suggest that previously acquired fMRI studies incorporating simple block-design motor tasks could be mined retrospectively for assessment of the resting-state connectivity.

Motor and sensory function of the esophagus: revelations through ultrasound imaging.

Science.gov (United States)

Mittal, Ravinder K

2005-04-01

Catheter based high frequency intraluminal ultrasound (HFIUS) imaging is a powerful tool to study esophageal sensory and motor function and dysfunction in vivo in humans. It has provided a number of important insights into the longitudinal muscle function of the esophagus. Based on the ultrasound images and intraluminal pressure recordings, it is clear that there is synchrony in the timing as well as the amplitude of contraction between the circular and the longitudinal muscle layers of the esophagus in normal subjects. On the other hand, in patients with spastic disorders of the esophagus, there is an asynchrony of contraction related to the timing and amplitude of contraction of the two muscle layers during peristalsis. Achalasia, diffuse esophageal spasm, and nutcracker esophagus (spastic motor disorders of the esophagus) are associated with hypertrophy of the circular as well as longitudinal muscle layers. A sustained contraction of the longitudinal muscle of the esophagus is temporally related to chest pain and heartburn and may very well be the cause of symptoms. Longitudinal muscle function of the esophagus can be studied in vivo in humans using dynamic ultrasound imaging. Longitudinal muscle dysfunction appears to be important in the motor and sensory disorders of the esophagus.

Physical activity and obesity mediate the association between childhood motor function and adolescents’ academic achievement

OpenAIRE

Kantomaa, Marko T.; Stamatakis, Emmanuel; Kankaanpää, Anna; Kaakinen, Marika; Rodriguez, Alina; Taanila, Anja; Ahonen, Timo; Järvelin, Marjo-Riitta; Tammelin, Tuija

2012-01-01

The global epidemic of obesity and physical inactivity may have detrimental implications for young people’s cognitive function and academic achievement. This prospective study investigated whether childhood motor function predicts later academic achievement via physical activity, fitness, and obesity. The study sample included 8,061 children from the Northern Finland Birth Cohort 1986, which contains data about parent-reported motor function at age 8 y and self-reported physical activity, pre...

[Functional and motor gastrointestinal disorders].

Science.gov (United States)

Mearin, Fermín; Rey, Enrique; Balboa, Agustín

2015-09-01

This article discusses the most interesting studies on functional and motor gastrointestinal disorders presented at Digestive Diseases Week (DDW), 2015. Researchers are still seeking biomarkers for irritable bowel syndrome and have presented new data. One study confirmed that the use of low-dose antidepressants has an antinociceptive effect without altering the psychological features of patients with functional dyspepsia. A contribution that could have immediate application is the use of transcutaneous electroacupuncture, which has demonstrated effectiveness in controlling nausea in patients with gastroparesis. New data have come to light on the importance of diet in irritable bowel syndrome, although the effectiveness of a low-FODMAP diet seems to be losing momentum with time. Multiple data were presented on the long-term efficacy of rifaximin therapy in patients with irritable bowel syndrome and diarrhoea. In addition, among other contributions, and more as a curiosity, a study evaluated the effect of histamine in the diet of patients with irritable bowel syndrome. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Iron insufficiency compromises motor neurons and their mitochondrial function in Irp2-null mice

KAUST Repository

Jeong, Suh Young; Crooks, Daniel R.; Wilson-Ollivierre, Hayden; Ghosh, Manik C.; Sougrat, Rachid; Lee, Jaekwon; Cooperman, Sharon; Mitchell, James B.; Beaumont, Carole; Rouault, Tracey A.

2011-01-01

Genetic ablation of Iron Regulatory Protein 2 (Irp2, Ireb2), which post-transcriptionally regulates iron metabolism genes, causes a gait disorder in mice that progresses to hind-limb paralysis. Here we have demonstrated that misregulation of iron metabolism from loss of Irp2 causes lower motor neuronal degeneration with significant spinal cord axonopathy. Mitochondria in the lumbar spinal cord showed significantly decreased Complex I and II activities, and abnormal morphology. Lower motor neurons appeared to be the most adversely affected neurons, and we show that functional iron starvation due to misregulation of iron import and storage proteins, including transferrin receptor 1 and ferritin, may have a causal role in disease. We demonstrated that two therapeutic approaches were beneficial for motor neuron survival. First, we activated a homologous protein, IRP1, by oral Tempol treatment and found that axons were partially spared from degeneration. Secondly, we genetically decreased expression of the iron storage protein, ferritin, to diminish functional iron starvation. These data suggest that functional iron deficiency may constitute a previously unrecognized molecular basis for degeneration of motor neurons in mice.

Iron insufficiency compromises motor neurons and their mitochondrial function in Irp2-null mice

KAUST Repository

Jeong, Suh Young

2011-10-07

Genetic ablation of Iron Regulatory Protein 2 (Irp2, Ireb2), which post-transcriptionally regulates iron metabolism genes, causes a gait disorder in mice that progresses to hind-limb paralysis. Here we have demonstrated that misregulation of iron metabolism from loss of Irp2 causes lower motor neuronal degeneration with significant spinal cord axonopathy. Mitochondria in the lumbar spinal cord showed significantly decreased Complex I and II activities, and abnormal morphology. Lower motor neurons appeared to be the most adversely affected neurons, and we show that functional iron starvation due to misregulation of iron import and storage proteins, including transferrin receptor 1 and ferritin, may have a causal role in disease. We demonstrated that two therapeutic approaches were beneficial for motor neuron survival. First, we activated a homologous protein, IRP1, by oral Tempol treatment and found that axons were partially spared from degeneration. Secondly, we genetically decreased expression of the iron storage protein, ferritin, to diminish functional iron starvation. These data suggest that functional iron deficiency may constitute a previously unrecognized molecular basis for degeneration of motor neurons in mice.

Parental questionnaire as a screening instrument for motor function at age five

DEFF Research Database (Denmark)

Nordbye-Nielsen, Kirsten; Kesmodel, Ulrik Schiøler

2014-01-01

, Pearson’s χ2-test, logistic regression analyses and sensitivity and specificity were used to assess the correlation between the questionnaire and the M-ABC test. Results: The best screening tool was six questions in combination: sensitivity 39.8%, specificity 87.1%. Asking if a health professional ever......Introduction: No standardised method is used to determine motor function in children in general practice in Denmark. Our aim was to evaluate the correlation between a parental questionnaire assessing motor function at the age of five years and the clinical test Movement Assessment Battery...... for Children (M-ABC), and to assess whether one or more questions could be used to screen for motor problems at the age of five years. Methods: This study was based on a parental questionnaire containing ten questions. The M-ABC was used as the gold standard. n = 755 children. The Mann-Whitney rank sum test...

Awareness and use of Gross Motor Function Classification System ...

African Journals Online (AJOL)

Introduction The degree of disability in children with Cerebral Palsy (CP) can be evaluated with the Gross Motor Function Classification System (GMFCS), a valid tool which was designed for such purposes. However, there appears to be paucity of data on the awareness and use of the GMFCS particularly in the ...

Relationship between Motor Skill Competency and Executive Function in Children with Down's Syndrome

Science.gov (United States)

Schott, N.; Holfelder, B.

2015-01-01

Background: Previous studies suggest that children with Down's syndrome (DS), a genetically based neurodevelopmental disorder, demonstrate motor problems and cognitive deficits. The first aim of this study was to examine motor skills and executive functions (EFs) in school-age children with DS. The second aim was to investigate the relationship…

Wideband impedance measurements of DC motors under dynamic load conditions

NARCIS (Netherlands)

Diouf, F.; Buesink, Frederik Johannes Karel; Leferink, Frank Bernardus Johannes; Duval, Fabrice; Bensetti, Mohamed

2013-01-01

One of the principal conducted EMI(electromagnetic interferences) sources of low voltage DC (direct current) motors is the commutation occurring during rotation. In this paper the small-signal impedance of low voltage DC motors under different functioning modes, including the dynamic one is studied

Effect of physical therapy frequency on gross motor function in children with cerebral palsy

OpenAIRE

Park, Eun-Young

2016-01-01

[Purpose] This study attempted to investigate the effect of physical therapy frequency based on neurodevelopmental therapy on gross motor function in children with cerebral palsy. [Subjects and Methods] The study sample included 161 children with cerebral palsy who attended a convalescent or rehabilitation center for disabled individuals or a special school for children with physical disabilities in South Korea. Gross Motor Function Measure data were collected according to physical therapy fr...

Overexpression of survival motor neuron improves neuromuscular function and motor neuron survival in mutant SOD1 mice.

Science.gov (United States)

Turner, Bradley J; Alfazema, Neza; Sheean, Rebecca K; Sleigh, James N; Davies, Kay E; Horne, Malcolm K; Talbot, Kevin

2014-04-01

Spinal muscular atrophy results from diminished levels of survival motor neuron (SMN) protein in spinal motor neurons. Low levels of SMN also occur in models of amyotrophic lateral sclerosis (ALS) caused by mutant superoxide dismutase 1 (SOD1) and genetic reduction of SMN levels exacerbates the phenotype of transgenic SOD1(G93A) mice. Here, we demonstrate that SMN protein is significantly reduced in the spinal cords of patients with sporadic ALS. To test the potential of SMN as a modifier of ALS, we overexpressed SMN in 2 different strains of SOD1(G93A) mice. Neuronal overexpression of SMN significantly preserved locomotor function, rescued motor neurons, and attenuated astrogliosis in spinal cords of SOD1(G93A) mice. Despite this, survival was not prolonged, most likely resulting from SMN mislocalization and depletion of gems in motor neurons of symptomatic mice. Our results reveal that SMN upregulation slows locomotor deficit onset and motor neuron loss in this mouse model of ALS. However, disruption of SMN nuclear complexes by high levels of mutant SOD1, even in the presence of SMN overexpression, might limit its survival promoting effects in this specific mouse model. Studies in emerging mouse models of ALS are therefore warranted to further explore the potential of SMN as a modifier of ALS. Copyright © 2014 Elsevier Inc. All rights reserved.

Transfer function modeling of parallel connected two three-phase induction motor implementation using LabView platform

DEFF Research Database (Denmark)

Gunabalan, R.; Sanjeevikumar, P.; Blaabjerg, Frede

2015-01-01

This paper presents the transfer function modeling and stability analysis of two induction motors of same ratings and parameters connected in parallel. The induction motors are controlled by a single inverter and the entire drive system is modeled using transfer function in LabView. Further...

Aberrant supplementary motor complex and limbic activity during motor preparation in motor conversion disorder.

Science.gov (United States)

Voon, Valerie; Brezing, Christina; Gallea, Cecile; Hallett, Mark

2011-11-01

Conversion disorder (CD) is characterized by unexplained neurological symptoms presumed related to psychological issues. The main hypotheses to explain conversion paralysis, characterized by a lack of movement, include impairments in either motor intention or disruption of motor execution, and further, that hyperactive self-monitoring, limbic processing or top-down regulation from higher order frontal regions may interfere with motor execution. We have recently shown that CD with positive abnormal or excessive motor symptoms was associated with greater amygdala activity to arousing stimuli along with greater functional connectivity between the amygdala and supplementary motor area. Here we studied patients with such symptoms focusing on motor initiation. Subjects performed either an internally or externally generated 2-button action selection task in a functional MRI study. Eleven CD patients without major depression and 11 age- and gender-matched normal volunteers were assessed. During both internally and externally generated movement, conversion disorder patients relative to normal volunteers had lower left supplementary motor area (SMA) (implicated in motor initiation) and higher right amygdala, left anterior insula, and bilateral posterior cingulate activity (implicated in assigning emotional salience). These findings were confirmed in a subgroup analysis of patients with tremor symptoms. During internally versus externally generated action in CD patients, the left SMA had lower functional connectivity with bilateral dorsolateral prefrontal cortices. We propose a theory in which previously mapped conversion motor representations may in an arousing context hijack the voluntary action selection system, which is both hypoactive and functionally disconnected from prefrontal top-down regulation. Copyright © 2011 Movement Disorder Society.

Aberrant supplementary motor complex and limbic activity during motor preparation in motor conversion disorder

Science.gov (United States)

Voon, V; Brezing, C; Gallea, C; Hallett, M

2014-01-01

Background Conversion disorder is characterized by unexplained neurological symptoms presumed related to psychological issues. The main hypotheses to explain conversion paralysis, characterized by a lack of movement, include impairments in either motor intention or disruption of motor execution, and further, that hyperactive self-monitoring, limbic processing or top-down regulation from higher order frontal regions may interfere with motor execution. We have recently shown that conversion disorder with positive abnormal or excessive motor symptoms was associated with greater amygdala activity to arousing stimuli along with greater functional connectivity between the amgydala and supplementary motor area. Here we studied patients with such symptoms focusing on motor initiation. Methods Subjects performed either an internally or externally generated two-button action selection task in a functional MRI study. Results Eleven conversion disorder patients without major depression and 11 age- and gender-matched normal volunteers were assessed. During both internally and externally generated movement, conversion disorder patients relative to normal volunteers had lower left supplementary motor area (SMA) (implicated in motor initiation) and higher right amygdala, left anterior insula and bilateral posterior cingulate activity (implicated in assigning emotional salience). These findings were confirmed in a subgroup analysis of patients with tremor symptoms. During internally versus externally generated action in CD patients, the left SMA had lower functional connectivity with bilateral dorsolateral prefrontal cortices. Conclusion We propose a theory in which previously mapped conversion motor representations may in an arousing context hijack the voluntary action selection system which is both hypoactive and functionally disconnected from prefrontal top-down regulation. PMID:21935985

Using non-invasive brain stimulation to augment motor training-induced plasticity

Directory of Open Access Journals (Sweden)

Pascual-Leone Alvaro

2009-03-01

Full Text Available Abstract Therapies for motor recovery after stroke or traumatic brain injury are still not satisfactory. To date the best approach seems to be the intensive physical therapy. However the results are limited and functional gains are often minimal. The goal of motor training is to minimize functional disability and optimize functional motor recovery. This is thought to be achieved by modulation of plastic changes in the brain. Therefore, adjunct interventions that can augment the response of the motor system to the behavioural training might be useful to enhance the therapy-induced recovery in neurological populations. In this context, noninvasive brain stimulation appears to be an interesting option as an add-on intervention to standard physical therapies. Two non-invasive methods of inducing electrical currents into the brain have proved to be promising for inducing long-lasting plastic changes in motor systems: transcranial magnetic stimulation (TMS and transcranial direct current stimulation (tDCS. These techniques represent powerful methods for priming cortical excitability for a subsequent motor task, demand, or stimulation. Thus, their mutual use can optimize the plastic changes induced by motor practice, leading to more remarkable and outlasting clinical gains in rehabilitation. In this review we discuss how these techniques can enhance the effects of a behavioural intervention and the clinical evidence to date.

Neural substrates underlying stimulation-enhanced motor skill learning after stroke.

Science.gov (United States)

Lefebvre, Stéphanie; Dricot, Laurence; Laloux, Patrice; Gradkowski, Wojciech; Desfontaines, Philippe; Evrard, Frédéric; Peeters, André; Jamart, Jacques; Vandermeeren, Yves

2015-01-01

Motor skill learning is one of the key components of motor function recovery after stroke, especially recovery driven by neurorehabilitation. Transcranial direct current stimulation can enhance neurorehabilitation and motor skill learning in stroke patients. However, the neural mechanisms underlying the retention of stimulation-enhanced motor skill learning involving a paretic upper limb have not been resolved. These neural substrates were explored by means of functional magnetic resonance imaging. Nineteen chronic hemiparetic stroke patients participated in a double-blind, cross-over randomized, sham-controlled experiment with two series. Each series consisted of two sessions: (i) an intervention session during which dual transcranial direct current stimulation or sham was applied during motor skill learning with the paretic upper limb; and (ii) an imaging session 1 week later, during which the patients performed the learned motor skill. The motor skill learning task, called the 'circuit game', involves a speed/accuracy trade-off and consists of moving a pointer controlled by a computer mouse along a complex circuit as quickly and accurately as possible. Relative to the sham series, dual transcranial direct current stimulation applied bilaterally over the primary motor cortex during motor skill learning with the paretic upper limb resulted in (i) enhanced online motor skill learning; (ii) enhanced 1-week retention; and (iii) superior transfer of performance improvement to an untrained task. The 1-week retention's enhancement driven by the intervention was associated with a trend towards normalization of the brain activation pattern during performance of the learned motor skill relative to the sham series. A similar trend towards normalization relative to sham was observed during performance of a simple, untrained task without a speed/accuracy constraint, despite a lack of behavioural difference between the dual transcranial direct current stimulation and sham

Acute changes in motor cortical excitability during slow oscillatory and constant anodal transcranial direct current stimulation

DEFF Research Database (Denmark)

Bergmann, Til Ole; Groppa, Sergiu; Seeger, Markus

2009-01-01

Transcranial oscillatory current stimulation has recently emerged as a noninvasive technique that can interact with ongoing endogenous rhythms of the human brain. Yet, there is still little knowledge on how time-varied exogenous currents acutely modulate cortical excitability. In ten healthy...... individuals we used on-line single-pulse transcranial magnetic stimulation (TMS) to search for systematic shifts in corticospinal excitability during anodal sleeplike 0.8-Hz slow oscillatory transcranial direct current stimulation (so-tDCS). In separate sessions, we repeatedly applied 30-s trials (two blocks...... at 20 min) of either anodal so-tDCS or constant tDCS (c-tDCS) to the primary motor hand area during quiet wakefulness. Simultaneously and time-locked to different phase angles of the slow oscillation, motor-evoked potentials (MEPs) as an index of corticospinal excitability were obtained...

Functional MRI (fMRI) on lesions in and around the motor and the eloquent cortices

International Nuclear Information System (INIS)

Hara, Yoshie; Nakamura, Mitsugu; Tamura, Shogo; Tamaki, Norihiko; Kitamura, Junji

1999-01-01

From the view point of neurosurgeons, to aim the preoperative localized diagnosis on the motor and the eloquent cortices and postoperative preservation of neurological functions, fMRI was carried for patients with lesions in and around the motor and the eloquent cortices. Even in cases of mechanical oppression or brain edema, the motor and the eloquent cortices are localized on cerebral gyri. In perioperative period, identification and preserving the motor and the eloquent cortices are important for keeping brain function. Twenty six preoperative cases and 3 normal healthy subjects were observed. Exercise enhanced fMRI was performed on 3 normal healthy subjects, fMRI with motor stimulation in 24 cases and fMRI with speech stimulation in 4 cases. The signal intensity increased in all cases responsing to both stimulations. But the signal intensity in 8 cases decreased in some regions by motor stimulation and 1 case by speech stimulation. The decrease of signal intensity in this study seems to be a clinically important finding and it will be required to examine the significance in future. (K.H.)

Permanent Magnet Eddy Current Loss Analysis of a Novel Motor Integrated Permanent Magnet Gear

DEFF Research Database (Denmark)

Zhang, Yuqiu; Lu, Kaiyuan; Ye, Yunyue

2012-01-01

In this paper, a new motor integrated permanent magnet gear (MIPMG) is discussed. The focus is on eddy current loss analysis associated to permanent magnets (PMs). A convenient model of MIPMG is provided based on 2-D field-motion coupled time-stepping finite element method for transient eddy...... current analysis. The model takes the eddy current effect of PMs into account in determination of the magnetic field in the air-gap and in the magnet regions. The eddy current losses generated in the magnets are properly interpreted. Design improvements for reducing the eddy current losses are suggested...

In vivo optogenetic tracing of functional corticocortical connections between motor forelimb areas

Directory of Open Access Journals (Sweden)

Riichiro eHira

2013-04-01

Full Text Available Interactions between distinct motor cortical areas are essential for coordinated motor behaviors. In rodents, the motor cortical forelimb areas are divided into at least two distinct areas: the rostral forelimb area (RFA and the caudal forelimb area (CFA. The RFA is thought to be an equivalent of the premotor cortex in primates, whereas the CFA is believed to be an equivalent of the primary motor cortex. Although reciprocal connections between the RFA and the CFA have been anatomically identified in rats, it is unknown whether there are functional connections between these areas that can induce postsynaptic spikes. In this study, we used an in vivo Channelrhodopsin-2 photostimulation method to trace the functional connections between the mouse RFA and CFA. Simultaneous electrical recordings were utilized to detect spiking activities induced by synaptic inputs originating from photostimulated areas. This method, in combination with anatomical tracing, demonstrated that the RFA receives strong functional projections from layer 2/3 and/or layer 5a, but not from layer 5b, of the CFA. Further, the CFA receives strong projections from layer 5b neurons of the RFA. The onset latency of electrical responses evoked in remote areas upon photostimulation of the other areas was approximately 10 ms, which is consistent with the synaptic connectivity between these areas. Our results suggest that neuronal activities in the RFA and the CFA during movements are formed through asymmetric reciprocal connections.

Longitudinal development of gross motor function among Dutch children and young adults with cerebral palsy: an investigation of motor growth curves.

Science.gov (United States)

Smits, Dirk-Wouter; Gorter, Jan Willem; Hanna, Steven E; Dallmeijer, Annet J; van Eck, Mirjam; Roebroeck, Marij E; Vos, Rimke C; Ketelaar, Marjolijn

2013-04-01

The aim of this study was to describe patterns for gross motor development by level of severity in a Dutch population of individuals with cerebral palsy (CP). This longitudinal study included 423 individuals (260 males, 163 females) with CP. The mean age at baseline was 9 years 6 months (SD 6y 2mo, range 1-22y). The level of severity of CP among participants, according to the Gross Motor Function Classification System (GMFCS), was 50% level I, 13% level II, 14% level III, 13% level IV, and 10% level V. Participants had been assessed up to four times with the Gross Motor Function Measure (GMFM-66) at 1- or 2-year intervals between 2002 and 2009. Data were analysed using non-linear mixed effects modelling. For each GMFCS level, patterns were created by contrasting a stable limit model (SLM) with a peak and decline model (PDM), followed by estimating limits and rates of gross motor development. The SLM showed a better fit for all GMFCS levels than the PDM. Within the SLM, significant differences between GMFCS levels were found for both the limits (higher values for lower GMFCS levels) and the rates (higher values for GMFCS levels I-II vs level IV and for GMFCS levels I-IV vs level V) of gross motor development. The results validate the existence of five distinct patterns for gross motor development by level of severity of CP. ©The Authors. Developmental Medicine & Child Neurology © 2013 Mac Keith Press.

Milling tool wear diagnosis by feed motor current signal using an artificial neural network

Energy Technology Data Exchange (ETDEWEB)

Khajavi, Mehrdad Nouri; Nasernia, Ebrahim; Rostaghi, Mostafa [Dept. of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran (Iran, Islamic Republic of)

2016-11-15

In this paper, a Multi-layer perceptron (MLP) neural network was used to predict tool wear in face milling. For this purpose, a series of experiments was conducted using a milling machine on a CK45 work piece. Tool wear was measured by an optical microscope. To improve the accuracy and reliability of the monitoring system, tool wear state was classified into five groups, namely, no wear, slight wear, normal wear, severe wear and broken tool. Experiments were conducted with the aforementioned tool wear states, and different machining conditions and data were extracted. An increase in current amplitude was observed as the tool wear increased. Furthermore, effects of parameters such as tool wear, feed, and cut depth on motor current consumption were analyzed. Considering the complexity of the wear state classification, a multi-layer neural network was used. The root mean square of motor current, feed, cut depth, and tool rpm were chosen as the input and amount of flank wear as the output of MLP. Results showed good performance of the designed tool wear monitoring system.

PERFORMANCE OPTIMIZATION OF LINEAR INDUCTION MOTOR BY EDDY CURRENT AND FLUX DENSITY DISTRIBUTION ANALYSIS

Directory of Open Access Journals (Sweden)

M. S. MANNA

2011-12-01

Full Text Available The development of electromagnetic devices as machines, transformers, heating devices confronts the engineers with several problems. For the design of an optimized geometry and the prediction of the operational behaviour an accurate knowledge of the dependencies of the field quantities inside the magnetic circuits is necessary. This paper provides the eddy current and core flux density distribution analysis in linear induction motor. Magnetic flux in the air gap of the Linear Induction Motor (LIM is reduced to various losses such as end effects, fringes, effect, skin effects etc. The finite element based software package COMSOL Multiphysics Inc. USA is used to get the reliable and accurate computational results for optimization the performance of Linear Induction Motor (LIM. The geometrical characteristics of LIM are varied to find the optimal point of thrust and minimum flux leakage during static and dynamic conditions.

Analytical Method of Malculation of the Current and Torque a Reluctance Stepper Motor via Fourier Series

Directory of Open Access Journals (Sweden)

Pavel Zaskalicky

2008-01-01

Full Text Available Reluctance stepper motors are becoming to be very attractive transducer to conversion of electric signal to the mechanical position. Due to its simple construction is reluctance machine considered a very reliable machine which not requiring any maintenance. Present paper proposes a mathematical method of an analytical calculus of a phase current and electromagnetic torque of the motor via Fourier series. Saturation effect and winding reluctance are neglected.

In Vivo Neuromechanics : Decoding Causal Motor Neuron Behavior with Resulting Musculoskeletal Function

NARCIS (Netherlands)

Sartori, Massimo; Yavuz, Utku; Farina, Dario

2017-01-01

Human motor function emerges from the interaction between the neuromuscular and the musculoskeletal systems. Despite the knowledge of the mechanisms underlying neural and mechanical functions, there is no relevant understanding of the neuro-mechanical interplay in the neuro-musculo-skeletal system.

Submerged electricity generation plane with marine current-driven motors

Science.gov (United States)

Dehlsen, James G.P.; Dehlsen, James B.; Fleming, Alexander

2014-07-01

An underwater apparatus for generating electric power from ocean currents and deep water tides. A submersible platform including two or more power pods, each having a rotor with fixed-pitch blades, with drivetrains housed in pressure vessels that are connected by a transverse structure providing buoyancy, which can be a wing depressor, hydrofoil, truss, or faired tube. The platform is connected to anchors on the seafloor by forward mooring lines and a vertical mooring line that restricts the depth of the device in the water column. The platform operates using passive, rather than active, depth control. The wing depressor, along with rotor drag loads, ensures the platform seeks the desired operational current velocity. The rotors are directly coupled to a hydraulic pump that drives at least one constant-speed hydraulic-motor generator set and enables hydraulic braking. A fluidic bearing decouples non-torque rotor loads to the main shaft driving the hydraulic pumps.

Threshold values of ankle dorsiflexion and gross motor function in 60 children with cerebral palsy

DEFF Research Database (Denmark)

Rasmussen, Helle M; Svensson, Joachim; Thorning, Maria

2018-01-01

Background and purpose - Threshold values defining 3 categories of passive range of motion are used in the Cerebral Palsy follow-Up Program to guide clinical decisions. The aim of this study was to investigate the threshold values by testing the hypothesis that passive range of motion in ankle...... dorsiflexion is associated with gross motor function and that function differs between the groups of participants in each category. Patients and methods - We analyzed data from 60 ambulatory children (aged 5-9 years) with spastic cerebral palsy. Outcomes were passive range of motion in ankle dorsiflexion...... with flexed and extended knee and gross motor function (Gait Deviation Index, Gait Variable Score of the ankle, peak dorsiflexion during gait, 1-minute walk, Gross Motor Function Measure, the Pediatric Quality of Life Inventory Cerebral Palsy Module, and Pediatric Outcomes Data Collection Instrument). Results...

Modulation of mu rhythm desynchronization during motor imagery by transcranial direct current stimulation

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Kimura Akio

2010-06-01

Full Text Available Abstract Background The mu event-related desynchronization (ERD is supposed to reflect motor preparation and appear during motor imagery. The aim of this study is to examine the modulation of ERD with transcranial direct current stimulation (tDCS. Methods Six healthy subjects were asked to imagine their right hand grasping something after receiving a visual cue. Electroencephalograms (EEGs were recorded near the left M1. ERD of the mu rhythm (mu ERD by right hand motor imagery was measured. tDCS (10 min, 1 mA was used to modulate the cortical excitability of M1. Anodal, cathodal, and sham tDCS were tested in each subject with a randomized sequence on different days. Each condition was separated from the preceding one by more than 1 week in the same subject. Before and after tDCS, mu ERD was assessed. The motor thresholds (MT of the left M1 were also measured with transcranial magnetic stimulation. Results Mu ERD significantly increased after anodal stimulation, whereas it significantly decreased after cathodal stimulation. There was a significant correlation between mu ERD and MT. Conclusions Opposing effects on mu ERD based on the orientation of the stimulation suggest that mu ERD is affected by cortical excitability.

Comparison of experimental and theoretical reaction rail currents, rail voltages, and airgap fields for the linear induction motor research vehicle

Science.gov (United States)

Elliott, D. G.

1977-01-01

Measurements of reaction rail currents, reaction rail voltages, and airgap magnetic fields in tests of the Linear Induction Motor Research Vehicle (LIMRV) were compared with theoretical calculations from the mesh/matrix theory. It was found that the rail currents and magnetic fields predicted by the theory are within 20 percent of the measured currents and fields at most motor locations in most of the runs, but differ by as much as a factor of two in some cases. The most consistent difference is a higher experimental than theoretical magnetic field near the entrance of the motor and a lower experimental than theoretical magnetic field near the exit. The observed differences between the theoretical and experimental magnetic fields and currents do not account for the differences of as much as 26 percent between the theoretical and experimental thrusts.

Toxic gain of function from mutant FUS protein is crucial to trigger cell autonomous motor neuron loss.

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Scekic-Zahirovic, Jelena; Sendscheid, Oliver; El Oussini, Hajer; Jambeau, Mélanie; Sun, Ying; Mersmann, Sina; Wagner, Marina; Dieterlé, Stéphane; Sinniger, Jérome; Dirrig-Grosch, Sylvie; Drenner, Kevin; Birling, Marie-Christine; Qiu, Jinsong; Zhou, Yu; Li, Hairi; Fu, Xiang-Dong; Rouaux, Caroline; Shelkovnikova, Tatyana; Witting, Anke; Ludolph, Albert C; Kiefer, Friedemann; Storkebaum, Erik; Lagier-Tourenne, Clotilde; Dupuis, Luc

2016-05-17

FUS is an RNA-binding protein involved in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Cytoplasmic FUS-containing aggregates are often associated with concomitant loss of nuclear FUS Whether loss of nuclear FUS function, gain of a cytoplasmic function, or a combination of both lead to neurodegeneration remains elusive. To address this question, we generated knockin mice expressing mislocalized cytoplasmic FUS and complete FUS knockout mice. Both mouse models display similar perinatal lethality with respiratory insufficiency, reduced body weight and length, and largely similar alterations in gene expression and mRNA splicing patterns, indicating that mislocalized FUS results in loss of its normal function. However, FUS knockin mice, but not FUS knockout mice, display reduced motor neuron numbers at birth, associated with enhanced motor neuron apoptosis, which can be rescued by cell-specific CRE-mediated expression of wild-type FUS within motor neurons. Together, our findings indicate that cytoplasmic FUS mislocalization not only leads to nuclear loss of function, but also triggers motor neuron death through a toxic gain of function within motor neurons. © 2016 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

Calculation of Industrial Power Systems Containing Induction Motors

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Gheorghe Hazi

2014-09-01

Full Text Available The current paper proposes two methods and algorithms for determining the operating regimes of industrial electrical networks which include induction motors. The two methods presented are based on specific principles for calculating electrical networks: Newton-Raphson and Backward-Forward for iteratively determining currents and voltages. The particularity of this paper is how the driven load influences the determination of the motors operating regimes. For the industrial machines driven by motors we take into account the characteristic of the resistant torque depending on speed. In this way, at the electrical busbars to which motors are connected, the active and the reactive power absorbed are calculated as a function of voltage as opposed to a regular consumer busbar. The algorithms for the two methods are presented. Finally, a numerical study for a test network is realized and the convergence is analyzed.

Recycling of electrical motors by automatic disassembly

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Karlsson, Björn; Järrhed, Jan-Ove

2000-04-01

This paper presents a robotized workstation for end-of-life treatment of electrical motors with an electrical effect of about 1 kW. These motors can, for example, be found in washing machines and in industry. There are two main steps in the work. The first step is an inspection whereby the functionality of the motor is checked and classification either for re-use or for disassembly is done. In the second step the motors classified for disassembly are disassembled in a robotized automatic station. In the initial step measurements are performed during a start-up sequence of about 1 s. By measuring the rotation speed and the current and voltage of the three phases of the motor classification for either reuse or disassembly can be done. During the disassembly work, vision data are fused in order to classify the motors according to their type. The vision system also feeds the control system of the robot with various object co-ordinates, to facilitate correct operation of the robot. Finally, tests with a vision system and eddy-current equipment are performed to decide whether all copper has been removed from the stator.

Relations of Preschoolers' Visual-Motor and Object Manipulation Skills With Executive Function and Social Behavior.

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MacDonald, Megan; Lipscomb, Shannon; McClelland, Megan M; Duncan, Rob; Becker, Derek; Anderson, Kim; Kile, Molly

2016-12-01

The purpose of this article was to examine specific linkages between early visual-motor integration skills and executive function, as well as between early object manipulation skills and social behaviors in the classroom during the preschool year. Ninety-two children aged 3 to 5 years old (M age  = 4.31 years) were recruited to participate. Comprehensive measures of visual-motor integration skills, object manipulation skills, executive function, and social behaviors were administered in the fall and spring of the preschool year. Our findings indicated that children who had better visual-motor integration skills in the fall had better executive function scores (B = 0.47 [0.20], p gender, Head Start status, and site location, but not after controlling for children's baseline levels of executive function. In addition, children who demonstrated better object manipulation skills in the fall showed significantly stronger social behavior in their classrooms (as rated by teachers) in the spring, including more self-control (B - 0.03 [0.00], p social behavior in the fall and other covariates. Children's visual-motor integration and object manipulation skills in the fall have modest to moderate relations with executive function and social behaviors later in the preschool year. These findings have implications for early learning initiatives and school readiness.

Reduced sensory synaptic excitation impairs motor neuron function via Kv2.1 in spinal muscular atrophy.

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Fletcher, Emily V; Simon, Christian M; Pagiazitis, John G; Chalif, Joshua I; Vukojicic, Aleksandra; Drobac, Estelle; Wang, Xiaojian; Mentis, George Z

2017-07-01

Behavioral deficits in neurodegenerative diseases are often attributed to the selective dysfunction of vulnerable neurons via cell-autonomous mechanisms. Although vulnerable neurons are embedded in neuronal circuits, the contributions of their synaptic partners to disease process are largely unknown. Here we show that, in a mouse model of spinal muscular atrophy (SMA), a reduction in proprioceptive synaptic drive leads to motor neuron dysfunction and motor behavior impairments. In SMA mice or after the blockade of proprioceptive synaptic transmission, we observed a decrease in the motor neuron firing that could be explained by the reduction in the expression of the potassium channel Kv2.1 at the surface of motor neurons. Chronically increasing neuronal activity pharmacologically in vivo led to a normalization of Kv2.1 expression and an improvement in motor function. Our results demonstrate a key role of excitatory synaptic drive in shaping the function of motor neurons during development and the contribution of its disruption to a neurodegenerative disease.

Iron insufficiency compromises motor neurons and their mitochondrial function in Irp2-null mice.

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Suh Young Jeong

Full Text Available Genetic ablation of Iron Regulatory Protein 2 (Irp2, Ireb2, which post-transcriptionally regulates iron metabolism genes, causes a gait disorder in mice that progresses to hind-limb paralysis. Here we have demonstrated that misregulation of iron metabolism from loss of Irp2 causes lower motor neuronal degeneration with significant spinal cord axonopathy. Mitochondria in the lumbar spinal cord showed significantly decreased Complex I and II activities, and abnormal morphology. Lower motor neurons appeared to be the most adversely affected neurons, and we show that functional iron starvation due to misregulation of iron import and storage proteins, including transferrin receptor 1 and ferritin, may have a causal role in disease. We demonstrated that two therapeutic approaches were beneficial for motor neuron survival. First, we activated a homologous protein, IRP1, by oral Tempol treatment and found that axons were partially spared from degeneration. Secondly, we genetically decreased expression of the iron storage protein, ferritin, to diminish functional iron starvation. These data suggest that functional iron deficiency may constitute a previously unrecognized molecular basis for degeneration of motor neurons in mice.

Gear wear monitoring by modulation signal bispectrum based on motor current signal analysis

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Zhang, Ruiliang; Gu, Fengshou; Mansaf, Haram; Wang, Tie; Ball, Andrew D.

2017-09-01

Gears are important mechanical components for power transmissions. Tooth wear is one of the most common failure modes, which can present throughout a gear's lifetime. It is significant to accurately monitor gear wear progression in order to take timely predictive maintenances. Motor current signature analysis (MCSA) is an effective and non-intrusive approach which is able to monitor faults from both electrical and mechanical systems. However, little research has been reported in monitoring the gear wear and estimating its severity based on MCSA. This paper presents a novel gear wear monitoring method through a modulation signal bispectrum based motor current signal analysis (MSB-MCSA). For a steady gear transmission, it is inevitable to exist load and speed oscillations due to various errors including wears. These oscillations can induce small modulations in the current signals of the driving motor. MSB is particularly effective in characterising such small modulation signals. Based on these understandings, the monitoring process was implemented based on the current signals from a run-to-failure test of an industrial two stages helical gearbox under a moderate accelerated fatigue process. At the initial operation of the test, MSB analysis results showed that the peak values at the bifrequencies of gear rotations and the power supply can be effective monitoring features for identifying faulty gears and wear severity as they exhibit agreeable changes with gear loads. A monotonically increasing trend established by these features allows a clear indication of the gear wear progression. The dismantle inspection at 477 h of operation, made when one of the monitored features is about 123% higher than its baseline, has found that there are severe scuffing wear marks on a number of tooth surfaces on the driving gear, showing that the gear endures a gradual wear process during its long test operation. Therefore, it is affirmed that the MSB-MSCA approach proposed is reliable

Motor and somatosensory conversion disorder: a functional unawareness syndrome?

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Perez, David L; Barsky, Arthur J; Daffner, Kirk; Silbersweig, David A

2012-01-01

Although conversion disorder is closely connected to the origins of neurology and psychiatry, it remains poorly understood. In this article, the authors discuss neural and clinical parallels between lesional unawareness disorders and unilateral motor and somatosensory conversion disorder, emphasizing functional neuroimaging/disease correlates. Authors suggest that a functional-unawareness neurobiological framework, mediated by right hemisphere-lateralized, large-scale brain network dysfunction, may play a significant role in the neurobiology of conversion disorder. The perigenual anterior cingulate and the posterior parietal cortices are detailed as important in disease pathophysiology. Further investigations will refine the functional-unawareness concept, clarify the role of affective circuits, and delineate the process through which functional neurologic symptoms emerge.

On the relationship between motor performance and executive functioning in children with intellectual disabilities.

NARCIS (Netherlands)

Hartman, E.; Houwen, S.; Scherder, E.J.A.; Visscher, C.

2010-01-01

Background: It has been suggested that children with intellectual disabilities (ID) have motor problems and higher-order cognitive deficits. The aim of this study was to examine the motor skills and executive functions in school-age children with borderline and mild ID. The second aim was to

On the relationship between motor performance and executive functioning in children with intellectual disabilities

NARCIS (Netherlands)

Hartman, E.; Houwen, S.; Scherder, E.; Visscher, C.

Background It has been suggested that children with intellectual disabilities (ID) have motor problems and higher-order cognitive deficits. The aim of this study was to examine the motor skills and executive functions in school-age children with borderline and mild ID. The second aim was to

Machinability evaluation of titanium alloys (Part 2)--Analyses of cutting force and spindle motor current.

Science.gov (United States)

Kikuchi, Masafumi; Okuno, Osamu

2004-12-01

To establish a method of determining the machinability of dental materials for CAD/CAM systems, the machinability of titanium, two titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb), and free-cutting brass was evaluated through cutting force and spindle motor current. The metals were slotted using a milling machine and square end mills at four cutting conditions. Both the static and dynamic components of the cutting force represented well the machinability of the metals tested: the machinability of Ti-6Al-4V and Ti-6Al-7Nb was worse than that of titanium, while that of free-cutting brass was better. On the other hand, the results indicated that the spindle motor current was not sensitive enough to detect the material difference among the titanium and its alloys.

A DESCRIPTIVE STUDY ON THE ASSESSMENT OF FUNCTIONAL MOTOR DISABILITY IN CHILDREN WITH CEREBRAL PALSY

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Wadugodapitiya .S .I

2015-08-01

Full Text Available Background: Cerebral palsy (CP is one of the most common conditions in childhood causing severe physical disability. Spastic paresis is the most common form of CP. According to the topographic classification, CP is divided into spastic hemiplegia, diplegia and quadriplegia. Distribution of functional motor disability is varied in each type of CP. Aims: To describe functional motor disability in children with cerebral palsy using standard scales. Method: This cross-sectional descriptive study included 93 children with cerebral palsy (CP. Functional motor disability of each type of spastic CP was assessed using standard scales. Results: The dominant sub-type of cerebral palsy in the present study was spastic diplegia. Most affected muscle with spasticity was gastrocnemius-soleus group of muscles. Active range of motion of foot eversion and dorsiflexion were the most affected movements in all the types of CP. In the overall sample, only 35% were able to walk independently. Majority of subjects with quadriplegia were in levels III and IV of Gross Motor Functional Classification Scale representing severe disability. There was a significant relationship observed between the muscle tone and range of motion of their corresponding joints as well as between the muscle tone of gastrocnemius-soleus group of muscles and the ankle components of Observational Gait Analysis. Conclusions: Results of the present study confirms the clinical impression of disability levels in each type of CP and showed that the assessment of functional motor disability in children with different types of spastic CP is useful in planning and evaluation of treatment options.

Structurofunctional resting-state networks correlate with motor function in chronic stroke

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Benjamin T. Kalinosky

2017-01-01

Conclusion: The results demonstrate that changes after a stroke in both intrinsic and network-based structurofunctional correlations at rest are correlated with motor function, underscoring the importance of residual structural connectivity in cortical networks.

Clinical studies of brain functional images by motor activation using single photon emission computed tomography

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Kawaguchi, Masahiro [Gifu Univ. (Japan). School of Medicine

1998-09-01

Thirty participants (10 normal controls; group A, 5 patients with brain tumors located near central sulcus without hemiparesis; group B, 10 patients with brain tumors located near central sulcus with hemiparesis; group C, and 5 patients with brain tumors besides the central regions with hemiparesis; group D) were enrolled. The images were performed by means of split-dose method with {sup 99m}Tc-ECD at rest condition (SPECT 1) and during hand grasping (SPECT 2). The activation SPECT were obtained by subtracting SPECT 1 from SPECT 2, and the functional mapping was made by the strict registration of the activation SPECT with 3D MRI. To evaluate the changes of CBF (%{Delta}CBF) of the sensorimotor and supplementary motor areas on the functional mapping, ratio of the average counts of SPECT 1 and SPECT 2 was calculated and statistically compared. The functional activation paradigms caused a significant increase of CBF in the sensorimotor area contra-lateral to the stimulated hand, although the sensorimotor area and the central sulcus in groups B and C were dislocated, compared with hemisphere of non-tumor side. The sensorimotor area ipsi-lateral to the stimulated hand could be detected in almost of all subjects. The supplementary motor area could be detected in all subjects. In group A, the average %{Delta}CBF were up 24.1{+-}4.3% in the contra-lateral sensorimotor area, and 22.3{+-}3.6% in the supplementary motor area, respectively. The average %{Delta}CBF in the contra-lateral sensorimotor area of group D was significantly higher than that of group A. The brain functional mapping by motor activation using SPECT could localize the area of cortical motor function in normal volunteers and patients with brain tumors. The changes of regional CBF by activation SPECT precisely assess the cortical motor function even in patients with brain tumors located near central sulcus. (K.H.)

Clinical studies of brain functional images by motor activation using single photon emission computed tomography

International Nuclear Information System (INIS)

Kawaguchi, Masahiro

1998-01-01

Thirty participants (10 normal controls; group A, 5 patients with brain tumors located near central sulcus without hemiparesis; group B, 10 patients with brain tumors located near central sulcus with hemiparesis; group C, and 5 patients with brain tumors besides the central regions with hemiparesis; group D) were enrolled. The images were performed by means of split-dose method with 99m Tc-ECD at rest condition (SPECT 1) and during hand grasping (SPECT 2). The activation SPECT were obtained by subtracting SPECT 1 from SPECT 2, and the functional mapping was made by the strict registration of the activation SPECT with 3D MRI. To evaluate the changes of CBF (%ΔCBF) of the sensorimotor and supplementary motor areas on the functional mapping, ratio of the average counts of SPECT 1 and SPECT 2 was calculated and statistically compared. The functional activation paradigms caused a significant increase of CBF in the sensorimotor area contra-lateral to the stimulated hand, although the sensorimotor area and the central sulcus in groups B and C were dislocated, compared with hemisphere of non-tumor side. The sensorimotor area ipsi-lateral to the stimulated hand could be detected in almost of all subjects. The supplementary motor area could be detected in all subjects. In group A, the average %ΔCBF were up 24.1±4.3% in the contra-lateral sensorimotor area, and 22.3±3.6% in the supplementary motor area, respectively. The average %ΔCBF in the contra-lateral sensorimotor area of group D was significantly higher than that of group A. The brain functional mapping by motor activation using SPECT could localize the area of cortical motor function in normal volunteers and patients with brain tumors. The changes of regional CBF by activation SPECT precisely assess the cortical motor function even in patients with brain tumors located near central sulcus. (K.H.)

Human Motor Cortex Functional Changes in Acute Stroke: Gender Effects

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Di Lazzaro, Vincenzo; Pellegrino, Giovanni; Di Pino, Giovanni; Ranieri, Federico; Lotti, Fiorenza; Florio, Lucia; Capone, Fioravante

2016-01-01

The acute phase of stroke is accompanied by functional changes in the activity and interplay of both hemispheres. In healthy subjects, gender is known to impact the functional brain organization. We investigated whether gender influences also acute stroke functional changes. In thirty-five ischemic stroke patients, we evaluated the excitability of the affected (AH) and unaffected hemisphere (UH) by measuring resting and active motor threshold (AMT) and motor-evoked potential amplitude under baseline conditions and after intermittent theta burst stimulation (iTBS) of AH. We also computed an index of the excitability balance between the hemispheres, laterality indexes (LI), to evidence hemispheric asymmetry. AMT differed significantly between AH and UH only in the male group (p = 0.004), not in females (p > 0.200), and both LIAMT and LIRMT were significantly higher in males than in females (respectively p = 0.033 and p = 0.042). LTP-like activity induced by iTBS in AH was more frequent in females. Gender influences the functional excitability changes that take place after human stroke and the level of LTP that can be induced by repetitive stimulation. This knowledge is of high value in the attempt of individualizing to different genders any non-invasive stimulation strategy designed to foster stroke recovery. PMID:26858590

The central role of trunk control in the gross motor function of children with cerebral palsy

DEFF Research Database (Denmark)

Curtis, Derek John; Butler, Penny; Saavedra, Sandy

2015-01-01

. The participants were tested using the Gross Motor Function Measure (GMFM), the Pediatric Evaluation of Disability Inventory (PEDI), and the Segmental Assessment of Trunk Control (SATCo). Results Linear regression analysis showed a positive relationship between the segmental level of trunk control and age......, with both gross motor function and mobility. Segmental trunk control measured using the SATCo could explain between 38% and 40% of variation in GMFM and between 32% and 37% of variation in PEDI. Interpretation This study suggests a strong association between segmental trunk postural control and gross motor...

Split-phase motor running as capacitor starts motor and as capacitor run motor

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Yahaya Asizehi ENESI

2016-07-01

Full Text Available In this paper, the input parameters of a single phase split-phase induction motor is taken to investigate and to study the output performance characteristics of capacitor start and capacitor run induction motor. The value of these input parameters are used in the design characteristics of capacitor run and capacitor start motor with each motor connected to rated or standard capacitor in series with auxiliary winding or starting winding respectively for the normal operational condition. The magnitude of capacitor that will develop maximum torque in capacitor start motor and capacitor run motor are investigated and determined by simulation. Each of these capacitors is connected to the auxiliary winding of split-phase motor thereby transforming it into capacitor start or capacitor run motor. The starting current and starting torque of the split-phase motor (SPM, capacitor run motor (CRM and capacitor star motor (CSM are compared for their suitability in their operational performance and applications.

Robust quasi NID current and flux control of an induction motor for position control

NARCIS (Netherlands)

van Duijnhoven, M.; Blachuta, M.J.

1999-01-01

In the paper, a new control design method called Dynamic Contraction method is applied to the flux and quadrature current robust control of an induction motor operated using the field orientation principle. The resulting input-output decoupled and linearized drive is then used for time-optimal

Cathodal Transcranial Direct Current Stimulation Over Left Dorsolateral Prefrontal Cortex Area Promotes Implicit Motor Learning in a Golf Putting Task.

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Zhu, Frank F; Yeung, Andrew Y; Poolton, Jamie M; Lee, Tatia M C; Leung, Gilberto K K; Masters, Rich S W

2015-01-01

Implicit motor learning is characterized by low dependence on working memory and stable performance despite stress, fatigue, or multi-tasking. However, current paradigms for implicit motor learning are based on behavioral interventions that are often task-specific and limited when applied in practice. To investigate whether cathodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (DLPFC) area during motor learning suppressed working memory activity and reduced explicit verbal-analytical involvement in movement control, thereby promoting implicit motor learning. Twenty-seven healthy individuals practiced a golf putting task during a Training Phase while receiving either real cathodal tDCS stimulation over the left DLPFC area or sham stimulation. Their performance was assessed during a Test phase on another day. Verbal working memory capacity was assessed before and after the Training Phase, and before the Test Phase. Compared to sham stimulation, real stimulation suppressed verbal working memory activity after the Training Phase, but enhanced golf putting performance during the Training Phase and the Test Phase, especially when participants were required to multi-task. Cathodal tDCS over the left DLPFC may foster implicit motor learning and performance in complex real-life motor tasks that occur during sports, surgery or motor rehabilitation. Copyright © 2015 Elsevier Inc. All rights reserved.

A comparative study of using spindle motor power and eddy current for the detection of tool conditions in milling processes

OpenAIRE

Abbass, JK; Al-Habaibeh, A

2015-01-01

This paper investigates the use of the power of the driving motor of a CNC spindle in comparison to two perpendicular eddy current sensors for the detection of tool wear in milling processes. Monitoring the power through the current profile is a low cost system which has been utilised in this study as an attempt to detect the fluctuation in the motor load as a result of the conditions of the cutting tool. Eddy current sensors are dedicated sensors that are installed on the spindle to measure ...

Atypical within- and between-hemisphere motor network functional connections in children with developmental coordination disorder and attention-deficit/hyperactivity disorder

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Kevin R. McLeod

2016-01-01

Full Text Available Developmental coordination disorder (DCD and attention-deficit hyperactivity disorder (ADHD are highly comorbid neurodevelopmental disorders; however, the neural mechanisms of this comorbidity are poorly understood. Previous research has demonstrated that children with DCD and ADHD have altered brain region communication, particularly within the motor network. The structure and function of the motor network in a typically developing brain exhibits hemispheric dominance. It is plausible that functional deficits observed in children with DCD and ADHD are associated with neurodevelopmental alterations in within- and between-hemisphere motor network functional connection strength that disrupt this hemispheric dominance. We used resting-state functional magnetic resonance imaging to examine functional connections of the left and right primary and sensory motor (SM1 cortices in children with DCD, ADHD and DCD + ADHD, relative to typically developing children. Our findings revealed that children with DCD, ADHD and DCD + ADHD exhibit atypical within- and between-hemisphere functional connection strength between SM1 and regions of the basal ganglia, as well as the cerebellum. Our findings further support the assertion that development of atypical motor network connections represents common and distinct neural mechanisms underlying DCD and ADHD. In children with DCD and DCD + ADHD (but not ADHD, a significant correlation was observed between clinical assessment of motor function and the strength of functional connections between right SM1 and anterior cingulate cortex, supplementary motor area, and regions involved in visuospatial processing. This latter finding suggests that behavioral phenotypes associated with atypical motor network development differ between individuals with DCD and those with ADHD.

The Functional Organization and Cortical Connections of Motor Cortex in Squirrels

Science.gov (United States)

Cooke, Dylan F.; Padberg, Jeffrey; Zahner, Tony

2012-01-01

Despite extraordinary diversity in the rodent order, studies of motor cortex have been limited to only 2 species, rats and mice. Here, we examine the topographic organization of motor cortex in the Eastern gray squirrel (Sciurus carolinensis) and cortical connections of motor cortex in the California ground squirrel (Spermophilus beecheyi). We distinguish a primary motor area, M1, based on intracortical microstimulation (ICMS), myeloarchitecture, and patterns of connectivity. A sensorimotor area between M1 and the primary somatosensory area, S1, was also distinguished based on connections, functional organization, and myeloarchitecture. We term this field 3a based on similarities with area 3a in nonrodent mammals. Movements are evoked with ICMS in both M1 and 3a in a roughly somatotopic pattern. Connections of 3a and M1 are distinct and suggest the presence of a third far rostral field, termed “F,” possibly involved in motor processing based on its connections. We hypothesize that 3a is homologous to the dysgranular zone (DZ) in S1 of rats and mice. Our results demonstrate that squirrels have both similar and unique features of M1 organization compared with those described in rats and mice, and that changes in 3a/DZ borders appear to have occurred in both lineages. PMID:22021916

Effects of 2-Year Cognitive⁻Motor Dual-Task Training on Cognitive Function and Motor Ability in Healthy Elderly People: A Pilot Study.

Science.gov (United States)

Morita, Emiko; Yokoyama, Hisayo; Imai, Daiki; Takeda, Ryosuke; Ota, Akemi; Kawai, Eriko; Suzuki, Yuta; Okazaki, Kazunobu

2018-05-11

We aimed to examine the effect of 2-year cognitive⁻motor dual-task (DT) training on cognitive functions and motor ability of healthy elderly people without marked cognitive impairment. From the 25 participants of our 12-week DT trial conducted in 2014, we recruited 8 subjects who voluntarily participated in a new DT training program once a week for 2 years (exercise (EX) group). Their cognitive functions were evaluated by the Modified Mini-Mental State (3MS) examination and the Trail Making Test, and results were compared with those of the 11 subjects who discontinued the training and did not perform any types of exercise for 2 years (non-exercise (NO) group). Subjects in the NO group showed deterioration in the 3MS examination results, especially in the cognitive domain of attention. Meanwhile, participation in DT training maintained the scores in almost all domains of cognitive function, as well as the total 3MS scores. However, both groups had impaired quadriceps muscle strength and motor ability after the 2-year observation period. These results suggest that participating in exercise program comprising DT training for 2 years may be beneficial for maintaining the broad domains of cognitive function in healthy elderly people, although further verification is needed.

Effects of 2-Year Cognitive–Motor Dual-Task Training on Cognitive Function and Motor Ability in Healthy Elderly People: A Pilot Study

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Emiko Morita

2018-05-01

Full Text Available We aimed to examine the effect of 2-year cognitive–motor dual-task (DT training on cognitive functions and motor ability of healthy elderly people without marked cognitive impairment. From the 25 participants of our 12-week DT trial conducted in 2014, we recruited 8 subjects who voluntarily participated in a new DT training program once a week for 2 years (exercise (EX group. Their cognitive functions were evaluated by the Modified Mini-Mental State (3MS examination and the Trail Making Test, and results were compared with those of the 11 subjects who discontinued the training and did not perform any types of exercise for 2 years (non-exercise (NO group. Subjects in the NO group showed deterioration in the 3MS examination results, especially in the cognitive domain of attention. Meanwhile, participation in DT training maintained the scores in almost all domains of cognitive function, as well as the total 3MS scores. However, both groups had impaired quadriceps muscle strength and motor ability after the 2-year observation period. These results suggest that participating in exercise program comprising DT training for 2 years may be beneficial for maintaining the broad domains of cognitive function in healthy elderly people, although further verification is needed.

Rotor position sensor switches currents in brushless dc motors

Science.gov (United States)

1965-01-01

Reluctance switch incorporated in an induction motor is used for sensing rotor position and switching armature circuits in a brushless dc motor. This device drives the solar array system of an unmanned space satellite.

Prediction of motor outcomes and activities of daily living function using diffusion tensor tractography in acute hemiparetic stroke patients.

Science.gov (United States)

Imura, Takeshi; Nagasawa, Yuki; Inagawa, Tetsuji; Imada, Naoki; Izumi, Hiroaki; Emoto, Katsuya; Tani, Itaru; Yamasaki, Hiroyuki; Ota, Yuichiro; Oki, Shuichi; Maeda, Tadanori; Araki, Osamu

2015-05-01

[Purpose] The efficacy of diffusion tensor imaging in the prediction of motor outcomes and activities of daily living function remains unclear. We evaluated the most appropriate diffusion tensor parameters and methodology to determine whether the region of interest- or tractography-based method was more useful for predicting motor outcomes and activities of daily living function in stroke patients. [Subjects and Methods] Diffusion tensor imaging data within 10 days after stroke onset were collected and analyzed for 25 patients. The corticospinal tract was analyzed. Fractional anisotropy, number of fibers, and apparent diffusion coefficient were used as diffusion tensor parameters. Motor outcomes and activities of daily living function were evaluated on the same day as diffusion tensor imaging and at 1 month post-onset. [Results] The fractional anisotropy value of the affected corticospinal tract significantly correlated with the motor outcome and activities of daily living function within 10 days post-onset and at 1 month post-onset. Tthere were no significant correlations between other diffusion tensor parameters and motor outcomes or activities of daily living function. [Conclusion] The fractional anisotropy value of the affected corticospinal tract obtained using the tractography-based method was useful for predicting motor outcomes and activities of daily living function in stroke patients.

Effects of 10 Hz and 20 Hz Transcranial Alternating Current Stimulation on Automatic Motor Control.

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Cappon, Davide; D'Ostilio, Kevin; Garraux, Gaëtan; Rothwell, John; Bisiacchi, Patrizia

2016-01-01

In a masked prime choice reaction task, presentation of a compatible prime increases the reaction time to the following imperative stimulus if the interval between mask and prime is around 80-250 ms. This is thought to be due to automatic suppression of the motor plan evoked by the prime, which delays reaction to the imperative stimulus. Oscillatory activity in motor networks around the beta frequency range of 20 Hz is important in suppression of movement. Transcranial alternating current at 20 Hz may be able to drive oscillations in the beta range. To investigate whether transcranial alternating current stimulation (tACS) at 20 Hz would increase automatic inhibition in a masked prime task. As a control we used 10 Hz tACS. Stimulation was delivered at alpha (10 Hz) and beta (20 Hz) frequency over the supplementary motor area and the primary motor cortex (simultaneous tACS of SMA-M1), which are part of the BG-cortical motor loop, during the execution of the subliminal masked prime left/right choice reaction task. We measured the effects on reaction times. Corticospinal excitability was assessed by measuring the amplitude of motor evoked potentials (MEPs) evoked in the first dorsal interosseous muscle by transcranial magnetic stimulation (TMS) over M1. The 10 and 20-Hz tACS over SMA-M1 had different effects on automatic inhibition. The 20 Hz tACS increased the duration of automatic inhibition whereas it was decreased by 10 Hz tACS. Neurophysiologically, 20 Hz tACS reduced the amplitude of MEPs evoked from M1, whereas there was no change after 10 Hz tACS. Automatic mechanisms of motor inhibition can be modulated by tACS over motor areas of cortex. tACS may be a useful additional tool to investigate the causal links between endogenous brain oscillations and specific cognitive processes. Copyright © 2016 Elsevier Inc. All rights reserved.

A novel wireless recording and stimulating multichannel epicortical grid for supplementing or enhancing the sensory-motor functions in monkey (Macaca fascicularis

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Antonio Giuliano Zippo

2015-05-01

Full Text Available Artificial brain-machine interfaces (BMIs represent a prospective step forward supporting or replacing faulty brain functions. So far, several obstacles, such as the energy supply, the portability and the biocompatibility, have been limiting their effective translation in advanced experimental or clinical applications. In this work, a novel 16 channel chronically implantable epicortical grid has been proposed. It provides wireless transmission of cortical recordings and stimulations, with induction current recharge. The grid has been chronically implanted in a non-human primate (Macaca fascicularis and placed over the somato-motor cortex such that 13 electrodes recorded or stimulated the primary motor cortex and 3 the primary somatosensory cortex, in the deeply anaesthetized animal. Cortical sensory and motor recordings and stimulations have been performed within 3 months from the implant. In detail, by delivering motor cortex epicortical single spot stimulations (1 to 8V, 1 to 10 Hz, 500ms, biphasic waves, we analyzed the motor topographic precision, evidenced by tunable finger or arm movements of the anesthetized animal. The responses to light mechanical peripheral sensory stimuli (blocks of 100 stimuli, each single stimulus being < 1ms and interblock intervals of 1.5 to 4 s have been analyzed. We found 150 to 250ms delayed cortical responses from fast finger touches, often spread to nearby motor stations. We also evaluated the grid electrical stimulus interference with somatotopic natural tactile sensory processing showing no suppressing interference with sensory stimulus detection. In conclusion, we propose a chronically implantable epicortical grid which can accommodate most of current technological restrictions, representing an acceptable candidate for BMI experimental and clinical uses.

HTS flywheel energy storage system with rotor shaft stabilized by feed-back control of armature currents of motor-generator

International Nuclear Information System (INIS)

Tsukamoto, O.; Utsunomiya, A.

2007-01-01

We propose an HTS bulk bearing flywheel energy system (FWES) with rotor shaft stabilization system using feed-back control of the armature currents of the motor-generator. In the proposed system the rotor shift has a pivot bearing at one end of the shaft and an HTS bulk bearing (SMB) at the other end. The fluctuation of the rotor shaft with SMB is damped by feed-back control of the armature currents of the motor-generator sensing the position of the rotor shaft. The method has merits that the fluctuations are damped without active control magnet bearings and extra devices which may deteriorate the energy storage efficiency and need additional costs. The principle of the method was demonstrated by an experiment using a model permanent magnet motor

HTS flywheel energy storage system with rotor shaft stabilized by feed-back control of armature currents of motor-generator

Science.gov (United States)

Tsukamoto, O.; Utsunomiya, A.

2007-10-01

We propose an HTS bulk bearing flywheel energy system (FWES) with rotor shaft stabilization system using feed-back control of the armature currents of the motor-generator. In the proposed system the rotor shift has a pivot bearing at one end of the shaft and an HTS bulk bearing (SMB) at the other end. The fluctuation of the rotor shaft with SMB is damped by feed-back control of the armature currents of the motor-generator sensing the position of the rotor shaft. The method has merits that the fluctuations are damped without active control magnet bearings and extra devices which may deteriorate the energy storage efficiency and need additional costs. The principle of the method was demonstrated by an experiment using a model permanent magnet motor.

Safety aspects of postanesthesia care unit discharge without motor function assessment after spinal anesthesia

DEFF Research Database (Denmark)

Aasvang, Eske Kvanner; Jørgensen, Christoffer Calov; Laursen, Mogens Berg

2017-01-01

Background: Postanesthesia care unit (PACU) discharge without observation of lower limb motor function after spinal anesthesia has been suggested to signifcantly reduce PACU stay and enhance resource optimization and early rehabilitation but without enough data to allow clinical recommendations...... or knee arthroplasty was noninferior to motor function assessment in achieving length of stay 4 days or less or 30-day readmissions. Because a nonsignifcant tendency toward increased adverse events during the frst 24h in the ward was discovered, further safety data are needed in patients without...

Magnetic Field Equivalent Current Analysis-Based Radial Force Control for Bearingless Permanent Magnet Synchronous Motors

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Huangqiu Zhu

2015-05-01

Full Text Available Bearingless permanent magnet synchronous motors (BPMSMs, with all advantages of permanent magnet motors (PMSMs and magnetic bearings, have become an important research direction in the bearingless motor field. To realize a stable suspension for the BPMSM, accurate decoupling control between the electromagnetic torque and radial suspension force is indispensable. In this paper, a concise and reliable analysis method based on a magnetic field equivalent current is presented. By this analysis method, the operation principle is analyzed theoretically, and the necessary conditions to produce a stable radial suspension force are confirmed. In addition, mathematical models of the torque and radial suspension force are established which is verified by the finite element analysis (FEA software ANSYS. Finally, an experimental prototype of a 2-4 poles surface-mounted BPMSM is tested with the customized control strategy. The simulation and experimental results have shown that the motor has good rotation and suspension performance, and validated the accuracy of the proposed analysis method and the feasibility of the control strategy.

Does Parent Report Gross Motor Function Level of Cerebral Palsy Children Impact on the Quality of Life in these Children?

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Pashmdarfard, Marzieh; Amini, Malek; Badv, Reza Shervin; Ghaffarzade Namazi, Narges; Rassafiani, Mehdi

2017-01-01

The aim of this study was to assess the effect of parent report gross motor function level of cerebral palsy (CP) children on the parent report quality of life of CP children. Sampling of this cross-sectional study was done in occupational therapy clinics and CP children's schools in 2016 in Zanjan, Iran. Samples size was 60 CP children aged 6-12 yr and for sampling method, a non-probability convenience was used. For assessing the quality of life of CP children the cerebral palsy quality of life (CP QOL) questionnaire and for assessing the level of gross motor function of CP children the Gross Motor Function Classification System Family Report Questionnaire (GMFCSFRQ) were used. The average age of children (22 males and 30 females) was 8.92 yr old (minimum 6 yr and maximum 12 yr). The relationship between the level of gross motor function and participation and physical health was direct and significant (r=0.65). The relationship between functioning, access to services and family health with the level of gross motor function was direct but was not significant ( P >0.05) and the relationship between pain and impact of disability and emotional well-being with the level of gross motor function was significant ( P quality of life of children with cerebral palsy. It means that the level of gross motor function cannot be used as a predictor of quality of life for children with cerebral palsy alone.

Does early communication mediate the relationship between motor ability and social function in children with cerebral palsy?

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Lipscombe, Belinda; Boyd, Roslyn N; Coleman, Andrea; Fahey, Michael; Rawicki, Barry; Whittingham, Koa

2016-01-01

Children diagnosed with neurodevelopmental conditions such as cerebral palsy (CP) are at risk of experiencing restrictions in social activities negatively impacting their subsequent social functioning. Research has identified motor and communication ability as being unique determinants of social function capabilities in children with CP, to date, no research has investigated whether communication is a mediator of the relationship between motor ability and social functioning. To investigate whether early communication ability at 24 months corrected age (ca.) mediates the relationship between early motor ability at 24 months ca. and later social development at 60 months ca. in a cohort of children diagnosed with cerebral palsy (CP). A cohort of 71 children (43 male) diagnosed with CP (GMFCS I=24, 33.8%, II=9, 12.7%, III=12, 16.9%, IV=10, 14.1%, V=16, 22.5%) were assessed at 24 and 60 months ca. Assessments included the Gross Motor Function Measure (GMFM), the Communication and Symbolic Behaviour Scales-Developmental Profile (CSBS-DP) Infant-Toddler Checklist and the Paediatric Evaluation of Disability Inventory (PEDI). A mediation model was examined using bootstrapping. Early communication skills mediated the relationship between early motor abilities and later social functioning, b=0.24 (95% CI=0.08-0.43 and the mediation model was significant, F (2, 68)=32.77, pcommunication ability partially mediates the relationship between early motor ability and later social function in children with CP. This demonstrates the important role of early communication in ongoing social development. Early identification of communication delay and enriched language exposure is crucial in this population. Copyright © 2016 Elsevier Ltd. All rights reserved.

Functional Analysis Identified Habit Reversal Components for the Treatment of Motor Tics

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Dufrene, Brad A.; Harpole, Lauren Lestremau; Sterling, Heather E.; Perry, Erin J.; Burton, Britney; Zoder-Martell, Kimberly

2013-01-01

This study included brief functional analyses and treatment for motor tics exhibited by two children with Tourette Syndrome. Brief functional analyses were conducted in an outpatient treatment center and results were used to develop individualized habit reversal procedures. Treatment data were collected in clinic for one child and in clinic and…

Factors predicting the instant effect of motor function after subthalamic nucleus deep brain stimulation in Parkinson's disease.

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Su, Xin-Ling; Luo, Xiao-Guang; Lv, Hong; Wang, Jun; Ren, Yan; He, Zhi-Yi

2017-01-01

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for Parkinson's disease (PD), the predictive effect of levodopa responsiveness on surgical outcomes was confirmed by some studies, however there were different conclusions about that through long- and short-term follow-ups. We aimed to investigate the factors which influence the predictive value of levodopa responsiveness, and discover more predictive factors of surgical outcomes. Twenty-three PD patients underwent bilateral STN-DBS and completed our follow-up. Clinical evaluations were performed 1 week before and 3 months after surgery. STN-DBS significantly improved motor function of PD patients after 3 months; preoperative levodopa responsiveness and disease subtype predicted the effect of DBS on motor function; gender, disease duration and duration of motor fluctuations modified the predictive effect of levodopa responsiveness on motor improvement; the duration of motor fluctuations and severity of preoperative motor symptoms modified the predictive effect of disease subtype on motor improvement. The intensity of levodopa responsiveness served as a predictor of motor improvement more accurately in female patients, patients with shorter disease duration or shorter motor fluctuations; PD patients with dominant axial symptoms benefit less from STN-DBS compared to those with limb-predominant symptoms, especially in their later disease stage.

The functional implications of motor, cognitive, psychiatric, and social problem-solving states in Huntington's disease.

Science.gov (United States)

Van Liew, Charles; Gluhm, Shea; Goldstein, Jody; Cronan, Terry A; Corey-Bloom, Jody

2013-01-01

Huntington's disease (HD) is a genetic, neurodegenerative disorder characterized by motor, cognitive, and psychiatric dysfunction. In HD, the inability to solve problems successfully affects not only disease coping, but also interpersonal relationships, judgment, and independent living. The aim of the present study was to examine social problem-solving (SPS) in well-characterized HD and at-risk (AR) individuals and to examine its unique and conjoint effects with motor, cognitive, and psychiatric states on functional ratings. Sixty-three participants, 31 HD and 32 gene-positive AR, were included in the study. Participants completed the Social Problem-Solving Inventory-Revised: Long (SPSI-R:L), a 52-item, reliable, standardized measure of SPS. Items are aggregated under five scales (Positive, Negative, and Rational Problem-Solving; Impulsivity/Carelessness and Avoidance Styles). Participants also completed the Unified Huntington's Disease Rating Scale functional, behavioral, and cognitive assessments, as well as additional neuropsychological examinations and the Symptom Checklist-90-Revised (SCL-90R). A structural equation model was used to examine the effects of motor, cognitive, psychiatric, and SPS states on functionality. The multifactor structural model fit well descriptively. Cognitive and motor states uniquely and significantly predicted function in HD; however, neither psychiatric nor SPS states did. SPS was, however, significantly related to motor, cognitive, and psychiatric states, suggesting that it may bridge the correlative gap between psychiatric and cognitive states in HD. SPS may be worth assessing in conjunction with the standard gamut of clinical assessments in HD. Suggestions for future research and implications for patients, families, caregivers, and clinicians are discussed.

Abnormal functional connectivity and cortical integrity influence dominant hand motor disability in multiple sclerosis: a multimodal analysis.

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Zhong, Jidan; Nantes, Julia C; Holmes, Scott A; Gallant, Serge; Narayanan, Sridar; Koski, Lisa

2016-12-01

Functional reorganization and structural damage occur in the brains of people with multiple sclerosis (MS) throughout the disease course. However, the relationship between resting-state functional connectivity (FC) reorganization in the sensorimotor network and motor disability in MS is not well understood. This study used resting-state fMRI, T1-weighted and T2-weighted, and magnetization transfer (MT) imaging to investigate the relationship between abnormal FC in the sensorimotor network and upper limb motor disability in people with MS, as well as the impact of disease-related structural abnormalities within this network. Specifically, the differences in FC of the left hemisphere hand motor region between MS participants with preserved (n = 17) and impaired (n = 26) right hand function, compared with healthy controls (n = 20) was investigated. Differences in brain atrophy and MT ratio measured at the global and regional levels were also investigated between the three groups. Motor preserved MS participants had stronger FC in structurally intact visual information processing regions relative to motor impaired MS participants. Motor impaired MS participants showed weaker FC in the sensorimotor and somatosensory association cortices and more severe structural damage throughout the brain compared with the other groups. Logistic regression analysis showed that regional MTR predicted motor disability beyond the impact of global atrophy whereas regional grey matter volume did not. More importantly, as the first multimodal analysis combining resting-state fMRI, T1-weighted, T2-weighted and MTR images in MS, we demonstrate how a combination of structural and functional changes may contribute to motor impairment or preservation in MS. Hum Brain Mapp 37:4262-4275, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The BACHD Rat Model of Huntington Disease Shows Specific Deficits in a Test Battery of Motor Function.

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Manfré, Giuseppe; Clemensson, Erik K H; Kyriakou, Elisavet I; Clemensson, Laura E; van der Harst, Johanneke E; Homberg, Judith R; Nguyen, Huu Phuc

2017-01-01

Rationale : Huntington disease (HD) is a progressive neurodegenerative disorder characterized by motor, cognitive and neuropsychiatric symptoms. HD is usually diagnosed by the appearance of motor deficits, resulting in skilled hand use disruption, gait abnormality, muscle wasting and choreatic movements. The BACHD transgenic rat model for HD represents a well-established transgenic rodent model of HD, offering the prospect of an in-depth characterization of the motor phenotype. Objective : The present study aims to characterize different aspects of motor function in BACHD rats, combining classical paradigms with novel high-throughput behavioral phenotyping. Methods : Wild-type (WT) and transgenic animals were tested longitudinally from 2 to 12 months of age. To measure fine motor control, rats were challenged with the pasta handling test and the pellet reaching test. To evaluate gross motor function, animals were assessed by using the holding bar and the grip strength tests. Spontaneous locomotor activity and circadian rhythmicity were assessed in an automated home-cage environment, namely the PhenoTyper. We then integrated existing classical methodologies to test motor function with automated home-cage assessment of motor performance. Results : BACHD rats showed strong impairment in muscle endurance at 2 months of age. Altered circadian rhythmicity and locomotor activity were observed in transgenic animals. On the other hand, reaching behavior, forepaw dexterity and muscle strength were unaffected. Conclusions : The BACHD rat model exhibits certain features of HD patients, like muscle weakness and changes in circadian behavior. We have observed modest but clear-cut deficits in distinct motor phenotypes, thus confirming the validity of this transgenic rat model for treatment and drug discovery purposes.

Enantiopure Functional Molecular Motors Obtained by a Switchable Chiral-Resolution Process

NARCIS (Netherlands)

van Leeuwen, Thomas; Gan, Jefri; Kistemaker, Jos C. M.; Pizzolato, Stefano F.; Chang, Mu-Chieh; Feringa, Ben L.

2016-01-01

Molecular switches, rotors, and motors play an important role in the development of nano-machines and devices, as well as responsive and adaptive functional materials. For unidirectional rotors based on chiral overcrowded alkenes, their stereochemical homogeneity is of crucial importance. Herein, a

Functional Brain Connectivity during Multiple Motor Imagery Tasks in Spinal Cord Injury

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Alkinoos Athanasiou

2018-01-01

Full Text Available Reciprocal communication of the central and peripheral nervous systems is compromised during spinal cord injury due to neurotrauma of ascending and descending pathways. Changes in brain organization after spinal cord injury have been associated with differences in prognosis. Changes in functional connectivity may also serve as injury biomarkers. Most studies on functional connectivity have focused on chronic complete injury or resting-state condition. In our study, ten right-handed patients with incomplete spinal cord injury and ten age- and gender-matched healthy controls performed multiple visual motor imagery tasks of upper extremities and walking under high-resolution electroencephalography recording. Directed transfer function was used to study connectivity at the cortical source space between sensorimotor nodes. Chronic disruption of reciprocal communication in incomplete injury could result in permanent significant decrease of connectivity in a subset of the sensorimotor network, regardless of positive or negative neurological outcome. Cingulate motor areas consistently contributed the larger outflow (right and received the higher inflow (left among all nodes, across all motor imagery categories, in both groups. Injured subjects had higher outflow from left cingulate than healthy subjects and higher inflow in right cingulate than healthy subjects. Alpha networks were less dense, showing less integration and more segregation than beta networks. Spinal cord injury patients showed signs of increased local processing as adaptive mechanism. This trial is registered with NCT02443558.

Spinal Metaplasticity in Respiratory Motor Control

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Gordon S Mitchell

2015-02-01

Full Text Available A hallmark feature of the neural system controlling breathing is its ability to exhibit plasticity. Less appreciated is the ability to exhibit metaplasticity, a change in the capacity to express plasticity (ie. plastic plasticity. Recent advances in our understanding of cellular mechanisms giving rise to respiratory motor plasticity lay the groundwork for (ongoing investigations of metaplasticity. This detailed understanding of respiratory metaplasticity will be essential as we harness metaplasticity to restore breathing capacity in clinical disorders that compromise breathing, such as cervical spinal injury, motor neuron disease and other neuromuscular diseases. In this brief review, we discuss key examples of metaplasticity in respiratory motor control, and our current understanding of mechanisms giving rise to spinal plasticity and metaplasticity in phrenic motor output; particularly after pre-conditioning with intermittent hypoxia. Progress in this area has led to the realization that similar mechanisms are operative in other spinal motor networks, including those governing limb movement. Further, these mechanisms can be harnessed to restore respiratory and non-respiratory motor function after spinal injury.

Effects of somatosensory electrical stimulation on motor function and cortical oscillations.

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Tu-Chan, Adelyn P; Natraj, Nikhilesh; Godlove, Jason; Abrams, Gary; Ganguly, Karunesh

2017-11-13

Few patients recover full hand dexterity after an acquired brain injury such as stroke. Repetitive somatosensory electrical stimulation (SES) is a promising method to promote recovery of hand function. However, studies using SES have largely focused on gross motor function; it remains unclear if it can modulate distal hand functions such as finger individuation. The specific goal of this study was to monitor the effects of SES on individuation as well as on cortical oscillations measured using EEG, with the additional goal of identifying neurophysiological biomarkers. Eight participants with a history of acquired brain injury and distal upper limb motor impairments received a single two-hour session of SES using transcutaneous electrical nerve stimulation. Pre- and post-intervention assessments consisted of the Action Research Arm Test (ARAT), finger fractionation, pinch force, and the modified Ashworth scale (MAS), along with resting-state EEG monitoring. SES was associated with significant improvements in ARAT, MAS and finger fractionation. Moreover, SES was associated with a decrease in low frequency (0.9-4 Hz delta) ipsilesional parietomotor EEG power. Interestingly, changes in ipsilesional motor theta (4.8-7.9 Hz) and alpha (8.8-11.7 Hz) power were significantly correlated with finger fractionation improvements when using a multivariate model. We show the positive effects of SES on finger individuation and identify cortical oscillations that may be important electrophysiological biomarkers of individual responsiveness to SES. These biomarkers can be potential targets when customizing SES parameters to individuals with hand dexterity deficits. NCT03176550; retrospectively registered.

Note: Cryogenic heat switch with stepper motor actuator

Energy Technology Data Exchange (ETDEWEB)

Melcher, B. S., E-mail: bsmelche@syr.edu; Timbie, P. T., E-mail: pttimbie@wisc.edu [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2015-12-15

A mechanical cryogenic heat switch has been developed using a commercially available stepper motor and control electronics. The motor requires 4 leads, each carrying a maximum, pulsed current of 0.5 A. With slight modifications of the stepper motor, the switch functions reliably in vacuum at temperatures between 300 K and 4 K. The switch generates a clamping force of 262 N at room temperature. At 4 K it achieves an “on state” thermal conductance of 5.04 mW/K and no conductance in the “off state.” The switch is optimized for cycling an adiabatic demagnetization refrigerator.

[Intraoperative magnetic resonance imaging-guided functional neuronavigation plus intraoperative neurophysiological monitoring for microsurgical resection of lesions involving hand motor area].

Science.gov (United States)

Miao, Xing-lu; Chen, Zhi-juan; Yang, Wei-dong; Wang, Zeng-guang; Yu, Qing; Yue, Shu-yuan; Zhang, Jian-ning

2013-01-15

To explore the methods and applications of intraoperative magnetic resonance imaging (iMRI)-guided functional neuronavigation plus intraoperative neurophysiological monitoring (IONM) for microsurgical resection of lesions involving hand motor area. A total of 16 patients with brain lesions adjacent to hand motor area were recruited from January 2011 to April 2012. All of them underwent neuronavigator-assisted microsurgery. Also IONM was conducted to further map hand motor area and epileptogenic focus. High-field iMRI was employed to update the anatomical and functional imaging date and verify the extent of lesion resection. Brain shifting during the functional neuronavigation was corrected by iMRI in 5 patients. Finally, total lesion resection was achieved in 13 cases and subtotal resection in 3 cases. At Months 3-12 post-operation, hand motor function improved (n = 10) or remained unchanged (n = 6). None of them had persistent neurological deficit. The postoperative seizure improvement achieved Enge II level or above in 9 cases of brain lesions complicated with secondary epilepsy. Intraoperative MRI, functional neuronavigation and neurophysiological monitoring technique are complementary in microsurgery of brain lesions involving hand motor area. Combined use of these techniques can obtain precise location of lesions and hand motor functional structures and allow a maximum resection of lesion and minimization of postoperative neurological deficits.