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Sample records for current motor function

  1. Effects of cerebellar transcranial alternating current stimulation on motor cortex excitability and motor function.

    Science.gov (United States)

    Naro, Antonino; Bramanti, Alessia; Leo, Antonino; Manuli, Alfredo; Sciarrone, Francesca; Russo, Margherita; Bramanti, Placido; Calabrò, Rocco Salvatore

    2017-01-07

    The cerebellum regulates several motor functions through two main mechanisms, the cerebellum-brain inhibition (CBI) and the motor surround inhibition (MSI). Although the exact cerebellar structures and functions involved in such processes are partially known, Purkinje cells (PC) and their surrounding interneuronal networks may play a pivotal role concerning CBI and MSI. Cerebellar transcranial alternating current stimulation (tACS) has been proven to shape specific cerebellar components in a feasible, safe, effective, and non-invasive manner. The aim of our study was to characterize the cerebellar structures and functions subtending CBI and MSI using a tACS approach. Fifteen healthy individuals underwent a cerebellar tACS protocol at 10, 50, and 300 Hz, or a sham-tACS over the right cerebellar hemisphere. We measured the tACS aftereffects on motor-evoked potential (MEP) amplitude, CBI induced by tACS (tiCBI) at different frequencies, MSI, and hand motor task performance. None of the participants had any side effect related to tACS. After 50-Hz tACS, we observed a clear tiCBI-50Hz weakening (about +30%, p  0.6). Our preliminary data suggest that PC may represent the last mediator of tiCBI and that the surrounding interneuronal network may have an important role in updating MSI, tiCBI, and M1 excitability during tonic muscle contraction, by acting onto the PC. The knowledge of these neurophysiological issues offers new cues to design innovative, non-invasive neuromodulation protocols to shape cerebellar-cerebral functions.

  2. Induction motor starting current

    Energy Technology Data Exchange (ETDEWEB)

    Arneaud, J.M.; Langman, R.A. [Tasmania Univ., Hobart, TAS (Australia)

    1995-12-31

    Large errors may occur if leakage path saturation is neglected when reduced-voltage test results are used to predict the direct-on-line starting current of induction motors. The results of applying three existing and two new methods for starting current prediction are compared with test data from 52 motors. A quantitative assessment is made of the probable reduction in error that would be achieved by increasing the number of available sets of reduced-voltage, locked rotor test results or by including slot design data. Guidelines are given for selecting an appropriate predictive method. (author). 4 tabs., 1 fig., 6 refs.

  3. Does transcranial direct current stimulation enhance cognitive and motor functions in the ageing brain? A systematic review and meta- analysis.

    Science.gov (United States)

    Summers, Jeffery J; Kang, Nyeonju; Cauraugh, James H

    2016-01-01

    The use of transcranial direct current stimulation (tDCS) to enhance cognitive and motor functions has enjoyed a massive increase in popularity. Modifying neuroplasticity via non-invasive cortical stimulation has enormous potential to slow or even reverse declines in functions associated with ageing. The current meta-analysis evaluated the effects of tDCS on cognitive and motor performance in healthy older adults. Of the 81 studies identified, 25 qualified for inclusion. A random effects model meta-analysis revealed a significant overall standardized mean difference equal to 0.53 (SE=0.09; medium heterogeneity: I(2)=57.08%; and high fail-safe: N=448). Five analyses on moderator variables indicated significant tDCS beneficial effects: (a) on both cognitive and motor task performances, (b) across a wide-range of cognitive tasks, (c) on specific brain areas, (d) stimulation offline (before) or online (during) the cognitive and motor tasks. Although the meta-analysis revealed robust support for enhancing both cognitive and motor performance, we outline a number of caveats on the use of tDCS.

  4. Constraint-Induced Movement Therapy Combined with Transcranial Direct Current Stimulation over Premotor Cortex Improves Motor Function in Severe Stroke: A Pilot Randomized Controlled Trial

    Science.gov (United States)

    Batista, Larissa M.; Nogueira, Lídia L. R. F.; de Oliveira, Eliane A.; de Carvalho, Antonio G. C.; Lima, Soriano S.; Santana, Jordânia R. M.; de Lima, Emerson C. C.; Fernández-Calvo, Bernardino

    2017-01-01

    Objective. We compared the effects of transcranial direct current stimulation at different cortical sites (premotor and motor primary cortex) combined with constraint-induced movement therapy for treatment of stroke patients. Design. Sixty patients were randomly distributed into 3 groups: Group A, anodal stimulation on premotor cortex and constraint-induced movement therapy; Group B, anodal stimulation on primary motor cortex and constraint-induced movement therapy; Group C, sham stimulation and constraint-induced movement therapy. Evaluations involved analysis of functional independence, motor recovery, spasticity, gross motor function, and muscle strength. Results. A significant improvement in primary outcome (functional independence) after treatment in the premotor group followed by primary motor group and sham group was observed. The same pattern of improvement was highlighted among all secondary outcome measures regarding the superior performance of the premotor group over primary motor and sham groups. Conclusions. Premotor cortex can contribute to motor function in patients with severe functional disabilities in early stages of stroke. This study was registered in ClinicalTrials.gov database (NCT 02628561). PMID:28250992

  5. Constraint-Induced Movement Therapy Combined with Transcranial Direct Current Stimulation over Premotor Cortex Improves Motor Function in Severe Stroke: A Pilot Randomized Controlled Trial.

    Science.gov (United States)

    Andrade, Suellen M; Batista, Larissa M; Nogueira, Lídia L R F; de Oliveira, Eliane A; de Carvalho, Antonio G C; Lima, Soriano S; Santana, Jordânia R M; de Lima, Emerson C C; Fernández-Calvo, Bernardino

    2017-01-01

    Objective. We compared the effects of transcranial direct current stimulation at different cortical sites (premotor and motor primary cortex) combined with constraint-induced movement therapy for treatment of stroke patients. Design. Sixty patients were randomly distributed into 3 groups: Group A, anodal stimulation on premotor cortex and constraint-induced movement therapy; Group B, anodal stimulation on primary motor cortex and constraint-induced movement therapy; Group C, sham stimulation and constraint-induced movement therapy. Evaluations involved analysis of functional independence, motor recovery, spasticity, gross motor function, and muscle strength. Results. A significant improvement in primary outcome (functional independence) after treatment in the premotor group followed by primary motor group and sham group was observed. The same pattern of improvement was highlighted among all secondary outcome measures regarding the superior performance of the premotor group over primary motor and sham groups. Conclusions. Premotor cortex can contribute to motor function in patients with severe functional disabilities in early stages of stroke. This study was registered in ClinicalTrials.gov database (NCT 02628561).

  6. Constraint-Induced Movement Therapy Combined with Transcranial Direct Current Stimulation over Premotor Cortex Improves Motor Function in Severe Stroke: A Pilot Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Suellen M. Andrade

    2017-01-01

    Full Text Available Objective. We compared the effects of transcranial direct current stimulation at different cortical sites (premotor and motor primary cortex combined with constraint-induced movement therapy for treatment of stroke patients. Design. Sixty patients were randomly distributed into 3 groups: Group A, anodal stimulation on premotor cortex and constraint-induced movement therapy; Group B, anodal stimulation on primary motor cortex and constraint-induced movement therapy; Group C, sham stimulation and constraint-induced movement therapy. Evaluations involved analysis of functional independence, motor recovery, spasticity, gross motor function, and muscle strength. Results. A significant improvement in primary outcome (functional independence after treatment in the premotor group followed by primary motor group and sham group was observed. The same pattern of improvement was highlighted among all secondary outcome measures regarding the superior performance of the premotor group over primary motor and sham groups. Conclusions. Premotor cortex can contribute to motor function in patients with severe functional disabilities in early stages of stroke. This study was registered in ClinicalTrials.gov database (NCT 02628561.

  7. The Use of Current Generators in Electrical Converter Drives for Stepper Motors

    Directory of Open Access Journals (Sweden)

    Emanoil Toma

    2014-09-01

    Full Text Available This paper presents some ways to realize electrical converters for stepper motor drives. The first part analyzes aspects for unipolar stepper motor and use of constant current generators. The second part present current sources based on peak limiting current trough the inductance of motor coil. A complete drive module for bipolar stepper motor was conceived and simulation results confirm their functionability.

  8. Does anodal transcranial direct current stimulation enhance excitability of the motor cortex and motor function in healthy individuals and subjects with stroke: a systematic review and meta-analysis.

    Science.gov (United States)

    Bastani, A; Jaberzadeh, S

    2012-04-01

    The primary aim of this review is to evaluate the effects of anodal transcranial direct current stimulation (a-tDCS) on corticomotor excitability and motor function in healthy individuals and subjects with stroke. The secondary aim is to find a-tDCS optimal parameters for its maximal effects. Electronic databases were searched for studies into the effect of a-tDCS when compared to no stimulation. Studies which met the inclusion criteria were assessed and methodological quality was examined using PEDro and Downs and Black (D&B) assessment tools. Data from seven studies revealed increase in corticomotor excitability with a small but significant effect size (0.31 [0.14, 0.48], p=0.0003) in healthy subjects and data from two studies in subjects with stroke indicated significant results with moderate effect size (0.59 [0.24, 0.93], p=0.001) in favor of a-tDCS. Likewise, studies examining motor function demonstrated a small and non-significant effect (0.39 [-0.17, 0.94], p=0.17) in subjects with stroke and a large but non-significant effect (0.92 [-1.02, 2.87], p=0.35) in healthy subjects in favor of improvement in motor function. The results also indicate that efficacy of a-tDCS is dependent on current density and duration of application. A-tDCS increases corticomotor excitability in both healthy individuals and subjects with stroke. The results also show a trend in favor of motor function improvement following a-tDCS. A-tDCS is a non-invasive, cheap and easy-to-apply modality which could be used as a stand-alone technique or as an adds-on technique to enhance corticomotor excitability and the efficacy of motor training approaches. However, the small sample size of the included studies reduces the strength of the presented evidences and any conclusion in this regard should be considered cautiously.

  9. 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.

  10. Treatment of functional motor disorders

    NARCIS (Netherlands)

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

    2014-01-01

    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

  11. Reducing current reversal time in electric motor control

    Science.gov (United States)

    Bredemann, Michael V

    2014-11-04

    The time required to reverse current flow in an electric motor is reduced by exploiting inductive current that persists in the motor when power is temporarily removed. Energy associated with this inductive current is used to initiate reverse current flow in the motor.

  12. Dyspraxia, motor function and visual-motor integration in autism.

    Science.gov (United States)

    Miller, M; Chukoskie, L; Zinni, M; Townsend, J; Trauner, D

    2014-08-01

    This project assessed dyspraxia in high-functioning school aged children with autism with a focus on Ideational Praxis. We examined the association of specific underlying motor function including eye movement with ideational dyspraxia (sequences of skilled movements) as well as the possible role of visual-motor integration in dyspraxia. We found that compared to IQ-, sex- and age-matched typically developing children, the children with autism performed significantly worse on: Ideational and Buccofacial praxis; a broad range of motor tests, including measures of simple motor skill, timing and accuracy of saccadic eye movements and motor coordination; and tests of visual-motor integration. Impairments in individual children with autism were heterogeneous in nature, although when we examined the praxis data as a function of a qualitative measure representing motor timing, we found that children with poor motor timing performed worse on all praxis categories and had slower and less accurate eye movements while those with regular timing performed as well as typical children on those same tasks. Our data provide evidence that both motor function and visual-motor integration contribute to dyspraxia. We suggest that dyspraxia in autism involves cerebellar mechanisms of movement control and the integration of these mechanisms with cortical networks implicated in praxis.

  13. Sliding Mode Control of Induction Motor Phase Currents

    DEFF Research Database (Denmark)

    Hansen, R.B.; Hattel, T.; Bork, J

    1995-01-01

    Sliding mode control of induction motor phase currents are investigated through development of two control concepts.......Sliding mode control of induction motor phase currents are investigated through development of two control concepts....

  14. Sliding Mode Control of Induction Motor Phase Currents

    DEFF Research Database (Denmark)

    Hansen, R.B.; Hattel, T.; Bork, J

    1995-01-01

    Sliding mode control of induction motor phase currents are investigated through development of two control concepts.......Sliding mode control of induction motor phase currents are investigated through development of two control concepts....

  15. Parietal transcranial direct current stimulation modulates primary motor cortex excitability.

    Science.gov (United States)

    Rivera-Urbina, Guadalupe Nathzidy; Batsikadze, Giorgi; Molero-Chamizo, Andrés; Paulus, Walter; Kuo, Min-Fang; Nitsche, Michael A

    2015-03-01

    The posterior parietal cortex is part of the cortical network involved in motor learning and is structurally and functionally connected with the primary motor cortex (M1). Neuroplastic alterations of neuronal connectivity might be an important basis for learning processes. These have however not been explored for parieto-motor connections in humans by transcranial direct current stimulation (tDCS). Exploring tDCS effects on parieto-motor cortical connectivity might be functionally relevant, because tDCS has been shown to improve motor learning. We aimed to explore plastic alterations of parieto-motor cortical connections by tDCS in healthy humans. We measured neuroplastic changes of corticospinal excitability via motor evoked potentials (MEP) elicited by single-pulse transcranial magnetic stimulation (TMS) before and after tDCS over the left posterior parietal cortex (P3), and 3 cm posterior or lateral to P3, to explore the spatial specificity of the effects. Furthermore, short-interval intracortical inhibition/intracortical facilitation (SICI/ICF) over M1, and parieto-motor cortical connectivity were obtained before and after P3 tDCS. The results show polarity-dependent M1 excitability alterations primarily after P3 tDCS. Single-pulse TMS-elicited MEPs, M1 SICI/ICF at 5 and 7 ms and 10 and 15 ms interstimulus intervals (ISIs), and parieto-motor connectivity at 10 and 15 ms ISIs were all enhanced by anodal stimulation. Single pulse-TMS-elicited MEPs, and parieto-motor connectivity at 10 and 15 ms ISIs were reduced by cathodal tDCS. The respective corticospinal excitability alterations lasted for at least 120 min after stimulation. These results show an effect of remote stimulation of parietal areas on M1 excitability. The spatial specificity of the effects and the impact on parietal cortex-motor cortex connections suggest a relevant connectivity-driven effect.

  16. The effects of anodal transcranial direct current stimulation and patterned electrical stimulation on spinal inhibitory interneurons and motor function in patients with spinal cord injury.

    Science.gov (United States)

    Yamaguchi, Tomofumi; Fujiwara, Toshiyuki; Tsai, Yun-An; Tang, Shuen-Chang; Kawakami, Michiyuki; Mizuno, Katsuhiro; Kodama, Mitsuhiko; Masakado, Yoshihisa; Liu, Meigen

    2016-06-01

    Supraspinal excitability and sensory input may play an important role for the modulation of spinal inhibitory interneurons and functional recovery among patients with incomplete spinal cord injury (SCI). Here, we investigated the effects of anodal transcranial direct current stimulation (tDCS) combined with patterned electrical stimulation (PES) on spinal inhibitory interneurons in patients with chronic incomplete SCI and in healthy individuals. Eleven patients with incomplete SCI and ten healthy adults participated in a single-masked, sham-controlled crossover study. PES involved stimulating the common peroneal nerve with a train of ten 100 Hz pulses every 2 s for 20 min. Anodal tDCS (1 mA) was simultaneously applied to the primary motor cortex that controls the tibialis anterior muscle. We measured reciprocal inhibition and presynaptic inhibition of a soleus H-reflex by stimulating the common peroneal nerve prior to tibial nerve stimulation, which elicits the H-reflex. The inhibition was assessed before, immediately after, 10 min after and 20 min after the stimulation. Compared with baseline, simultaneous application of anodal tDCS with PES significantly increased changes in disynaptic reciprocal inhibition and long-latency presynaptic inhibition in both healthy and SCI groups for at least 20 min after the stimulation (all, p stimulation (p = 0.004). In conclusion, anodal tDCS combined with PES could induce spinal plasticity and improve ankle movement in patients with incomplete SCI.

  17. Molecular motors and their functions in plants

    Science.gov (United States)

    Reddy, A. S.

    2001-01-01

    Molecular motors that hydrolyze ATP and use the derived energy to generate force are involved in a variety of diverse cellular functions. Genetic, biochemical, and cellular localization data have implicated motors in a variety of functions such as vesicle and organelle transport, cytoskeleton dynamics, morphogenesis, polarized growth, cell movements, spindle formation, chromosome movement, nuclear fusion, and signal transduction. In non-plant systems three families of molecular motors (kinesins, dyneins, and myosins) have been well characterized. These motors use microtubules (in the case of kinesines and dyneins) or actin filaments (in the case of myosins) as tracks to transport cargo materials intracellularly. During the last decade tremendous progress has been made in understanding the structure and function of various motors in animals. These studies are yielding interesting insights into the functions of molecular motors and the origin of different families of motors. Furthermore, the paradigm that motors bind cargo and move along cytoskeletal tracks does not explain the functions of some of the motors. Relatively little is known about the molecular motors and their roles in plants. In recent years, by using biochemical, cell biological, molecular, and genetic approaches a few molecular motors have been isolated and characterized from plants. These studies indicate that some of the motors in plants have novel features and regulatory mechanisms. The role of molecular motors in plant cell division, cell expansion, cytoplasmic streaming, cell-to-cell communication, membrane trafficking, and morphogenesis is beginning to be understood. Analyses of the Arabidopsis genome sequence database (51% of genome) with conserved motor domains of kinesin and myosin families indicates the presence of a large number (about 40) of molecular motors and the functions of many of these motors remain to be discovered. It is likely that many more motors with novel regulatory

  18. [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.

  19. Functional and motor gastrointestinal disorders.

    Science.gov (United States)

    Mearin, Fermín; Rey, Enrique; Balboa, Agustín

    2016-09-01

    This article discusses the most interesting presentations at Digestive Disease Week, held in San Diego, in the field of functional and motor gastrointestinal disorders. One of the most important contributions was undoubtedly the presentation of the new Rome IV diagnostic criteria for functional gastrointestinal disorders. We therefore devote some space in this article to explaining these new criteria in the most common functional disorders. In fact, there has already been discussion of data comparing Rome IV and Rome III criteria in the diagnosis of irritable bowel syndrome, confirming that the new criteria are somewhat more restrictive. From the physiopathological point of view, several studies have shown that the aggregation of physiopathological alterations increases symptom severity in distinct functional disorders. From the therapeutic point of view, more data were presented on the efficacy of acotiamide and its mechanisms of action in functional dyspepsia, the safety and efficacy of domperidone in patients with gastroparesis, and the efficacy of linaclotide both in irritable bowel syndrome and constipation. In irritable bowel syndrome, more data have come to light on the favourable results of a low FODMAP diet, with emphasis on its role in modifying the microbiota. Finally, long-term efficacy data were presented on the distinct treatment options in achalasia.

  20. Motor Coordination and Executive Functions

    Science.gov (United States)

    Michel, Eva

    2012-01-01

    Since Piaget, the view that motor and cognitive development are interrelated has gained wide acceptance. However, empirical research on this issue is still rare. Few studies show a correlation of performance in cognitive and motor tasks in typically developing children. More specifically, Diamond A. (2000) hypothesizes an involvement of executive…

  1. Motor Coordination and Executive Functions

    Science.gov (United States)

    Michel, Eva

    2012-01-01

    Since Piaget, the view that motor and cognitive development are interrelated has gained wide acceptance. However, empirical research on this issue is still rare. Few studies show a correlation of performance in cognitive and motor tasks in typically developing children. More specifically, Diamond A. (2000) hypothesizes an involvement of executive…

  2. Reactor coolant pump testing using motor current signatures analysis

    Energy Technology Data Exchange (ETDEWEB)

    Burstein, N.; Bellamy, J.

    1996-12-01

    This paper describes reactor coolant pump motor testing carried out at Florida Power Corporation`s Crystal River plant using Framatome Technologies` new EMPATH (Electric Motor Performance Analysis and Trending Hardware) system. EMPATH{trademark} uses an improved form of Motor Current Signature Analysis (MCSA), technology, originally developed at Oak Ridge National Laboratories, for detecting deterioration in the rotors of AC induction motors. Motor Current Signature Analysis (MCSA) is a monitoring tool for motor driven equipment that provides a non-intrusive means for detecting the presence of mechanical and electrical abnormalities in the motor and the driven equipment. The base technology was developed at the Oak Ridge National Laboratory as a means for determining the affects of aging and service wear specifically on motor-operated valves used in nuclear power plant safety systems, but it is applicable to a broad range of electric machinery. MCSA is based on the recognition that an electric motor (ac or dc) driving a mechanical load acts as an efficient and permanently available transducer by sensing mechanical load variations, large and small, long-term and rapid, and converting them into variations in the induced current generated in the motor windings. The motor current variations, resulting from changes in load caused by gears, pulleys, friction, bearings, and other conditions that may change over the life of the motor, are carried by the electrical cables powering the motor and are extracted at any convenient location along the motor lead. These variations modulate the 60 Hz carrier frequency and appear as sidebands in the spectral plot.

  3. 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.

  4. Induction Motor Speed Estimation by Using Spectral Current Analysis

    OpenAIRE

    2009-01-01

    An interesting application for the FFT analysis is related to the induction motor speed estimation based on spectral current analysis. The paper presents the possibility of induction motor speed estimation by using the current harmonics generated because of the rotor slots and of the eccentricity.

  5. Modeling and Simulation of Current Source Inverter Fed Synchronous Motor in Complex Frequency Domain Taking the Transition Zone From Induction Motor to Synchronous Motor Mode into Account

    Directory of Open Access Journals (Sweden)

    A.B. Chattopadhyay

    2014-02-01

    Full Text Available Modeling of synchronous motor plays a dominant role in designing complicated drive system for different applications, especially large blower fans etc for steel industries. As synchronous motor has no inherent starting torque generally it is started as an induction motor with the help of a damper winding and it pulls into synchronism under certain conditions. The present paper exactly concentrates on this particular zone of transition from induction motor to synchronous motor mode for a current source inverter fed synchronous motor drive system. Due to complexity of synchronous motor in terms of number of windings and finite amount of air gap saliency, direct modeling of such transition zone in time domain becomes cumbersome at the first instance of modeling. That is why the modeling in complex frequency domain (s-domain has been taken up using small perturbation model. Such a model clearly shows role of induction motor as noise function or disturbance function with respect to the open loop block diagram of synchronous motor. Such finding can be quantized in terms of important results and that is done in the present paper such that the results can help the designer for the successful design of a synchronous motor drive system.

  6. Influence of Random Potentials on the Current of the Molecular Motor Model

    Institute of Scientific and Technical Information of China (English)

    贾亚; 李家荣

    2001-01-01

    The current of the molecular motor model disturbed by random potentials, which involve the dichotomous and Ornstein-Uhlenbeck potentials, is studied using a finite-space correlation function. It is found that: (i) the amplitude and the correlation length of random potentials play opposing roles in the transport of the molecular motor model; (ii) a random potential with small amplitude and large correlation length is very useful in the molecular motor system.

  7. Current insights in the development of children's motor imagery ability.

    NARCIS (Netherlands)

    Spruijt, S.; Kamp, J. van der; Steenbergen, B.

    2015-01-01

    Over the last two decades, the number of studies on motor imagery in children has witnessed a large expansion. Most studies used the hand laterality judgment paradigm or the mental chronometry paradigm to examine motor imagery ability. The main objective of the current review is to collate these

  8. Current insights in the development of children's motor imagery ability

    NARCIS (Netherlands)

    Spruijt, S.; Kamp, J. van der; Steenbergen, B.

    2015-01-01

    Over the last two decades, the number of studies on motor imagery in children has witnessed a large expansion. Most studies used the hand laterality judgment paradigm or the mental chronometry paradigm to examine motor imagery ability. The main objective of the current review is to collate these

  9. Current insights in the development of children's motor imagery ability

    NARCIS (Netherlands)

    Spruijt, S.; Kamp, J. van der; Steenbergen, B.

    2015-01-01

    Over the last two decades, the number of studies on motor imagery in children has witnessed a large expansion. Most studies used the hand laterality judgment paradigm or the mental chronometry paradigm to examine motor imagery ability. The main objective of the current review is to collate these stu

  10. Current insights in the development of children's motor imagery ability.

    NARCIS (Netherlands)

    Spruijt, S.; Kamp, J. van der; Steenbergen, B.

    2015-01-01

    Over the last two decades, the number of studies on motor imagery in children has witnessed a large expansion. Most studies used the hand laterality judgment paradigm or the mental chronometry paradigm to examine motor imagery ability. The main objective of the current review is to collate these stu

  11. 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.

  12. Sport expert's motor imagery: functional imaging of professional motor skills and simple motor skills.

    Science.gov (United States)

    Wei, Gaoxia; Luo, Jing

    2010-06-23

    Numerous studies provide evidence that motor skill acquisition is associated with dynamic changes in cortical and subcortical regions. Athletes are a professional population who are engaged in extensive motor training for long periods. However, the neural substrates of extreme level motor performance have not been clarified. We used kinesthetic imagery task to induce the mental representation of sport expert's extraordinary performance in view of the shared substrates of executing movement and motor imagery. For the first time, we compared, through functional magnetic resonance imaging (fMRI), the pattern of cerebral activations in 12 professional divers and 12 normal people without extensive training, during imagery of professional skills and imagery of simple motor skills. The sport experts showed significant activation in the parahippocampus during imagery of professional skills relative to the novices, which might reflect the representation adapted to experience-related motor tasks. No significant difference was found between experts and novices when they imagined simple motor skills. These results indicated the experts might utilize their kinesthetic imagery more efficiently than novices, but only for the activity in which they had expertise. The sport experts also demonstrated more focused activation patterns in prefrontal areas in both of imagery tasks, which may be relevant to higher order of motor control during motor imagery. Moreover, this study suggested that the brains of sport experts could be regarded as the ideal subjects to explore the relationship between cerebral plasticity and learning of complex motor skills.

  13. 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.

  14. Impairments of Motor Function While Multitasking in HIV.

    Science.gov (United States)

    Kronemer, Sharif I; Mandel, Jordan A; Sacktor, Ned C; Marvel, Cherie L

    2017-01-01

    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.

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

    Science.gov (United States)

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

    2016-10-01

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

  16. Deep networks for motor control functions

    Directory of Open Access Journals (Sweden)

    Max eBerniker

    2015-03-01

    Full Text Available The motor system generates time-varying commands to move our limbs and body. Conventional descriptions of motor control and learning rely on dynamical representations of our body’s state (forward and inverse models, and control policies that must be integrated forward to generate feedforward time-varying commands; thus these are representations across space, but not time. Here we examine a new approach that directly represents both time-varying commands and the resulting state trajectories with a function; a representation across space and time. Since the output of this function includes time, it necessarily requires more parameters than a typical dynamical model. To avoid the problems of local minima these extra parameters introduce, we exploit recent advances in machine learning to build our function using a stacked autoencoder, or deep network. With initial and target states as inputs, this deep network can be trained to output an accurate temporal profile of the optimal command and state trajectory for a point-to-point reach of a nonlinear limb model, even when influenced by varying force fields. In a manner that mirrors motor babble, the network can also teach itself to learn through trial and error. Lastly, we demonstrate how this network can learn to optimize a cost objective. This functional approach to motor control is a sharp departure from the standard dynamical approach, and may offer new insights into the neural implementation of motor control.

  17. Motor function-related maladaptive plasticity in stroke: a review.

    Science.gov (United States)

    Jang, Sung Ho

    2013-01-01

    Brain plasticity can be classified as adaptive and maladaptive. Maladaptive plasticity indicates hindered functional recovery or the development of an unwanted symptom. Although a considerable amount is known about adaptive plasticity in stroke, relatively little is known of maladaptive plasticity. In the current study, previous studies on motor function-related maladaptive plasticity in stroke are reviewed in terms of compensatory movement pattern (CMP), delayed-onset involuntary abnormal movements (IAMs), and the ipsilateral motor pathway as a motor recovery mechanism. For successful stroke rehabilitation, it is important that the characteristics of maladaptive plasticity are accurately recognized. However, there is a lack of definitive evidence regarding the recognition of motor function-related maladaptive plasticity, although it seems that each of the three above-mentioned topics are involved. As for CMP, patients with a good neurological state as much as having a normal movement pattern, should be considered to have maladaptive plasticity, and in terms of the ipsilateral motor pathway, patients with bilateral innervations can be considered to have maladaptive plasticity. On the other hand, IAMs due to delayed neuronal degeneration should be ruled out in patients with delayed-onset IAMs. Therefore, for the accurate recognition of motor function-related maladaptive plasticity in stroke, a thorough evaluation of neurological state using brain mapping techniques is necessary, and subsequently, the prevention or intensive management of maladaptive plasticity is needed.

  18. Current control in inertial Brownian motors by noise recycling

    Science.gov (United States)

    Jia, Zheng-Lin; Li, Kai-Yi; Li, Chun; Yang, Chun-Yan; Mei, Dong-Cheng

    2015-03-01

    The transport properties of an inertial Brownian motor were numerically studied in the presence of recycled noise, which is obtained by re-injecting a fraction of the primary white noise after a processing time, being introduced into the system in a multiplicative way. The simulation results indicate that various parameters such as the external driving force, the friction coefficient, the mass of the particle, the recycling strength, and the delay time can induce the current reversal phenomenon when the sign of the recycling strength is in agreement with the sign of the external bias force, otherwise the current reversal cannot be observed. Additionally, the asymptotic mean velocity as a function of the delay time of the recycled noise always shows a resonance-like behavior with the presence of a maximum current. These results demonstrate that the delay time and the recycling strength of the recycled noise can be used as the feasible and flexible control parameters for the amplitude and direction of the current.

  19. [Functional and motor digestive disorders].

    Science.gov (United States)

    Mearin, Fermín; Rey, Enrique; Balboa, Agustín

    2013-10-01

    This article discusses the most interesting studies on functional and motility gastrointestinal disorders presented in Digestive Diseases Week (DDW) in 2013. New data were reported on the clinical importance of functional gastrointestinal disorders (FGID) and on how they can produce numerous disturbances such as inflammatory bowel disease. These disturbances are associated with somatic functional disease and particularly with fatigue. In addition, new data have emerged on the physiopathology of these disorders, with some studies reporting that environmental factors and events in early infancy can favor their development. Data were also presented on how bile acids can increase susceptibility to diarrhea in patients with irritable bowel syndrome (IBS) and on how the type of food intake can favor the development of symptoms. More data are available on the presence of underlying celiac disease in patients with IBS, which should prompt us to investigate this disease in our patients. Likewise, indiscriminate application of a gluten-free diet in patients with IBS has been shown not to produce a clear improvement. Regarding the physiopathology of functional dyspepsia (FD), results have been presented on how psychological factors can modify gastric accommodation and how this is in turn related to visceral hypersensitivity and gastric emptying. Regarding therapy, mirtazapine can improve symptoms and lead to weight gain in patients with severe FD and substantial weight loss. Results were presented on new drugs for IBS such as ibodutant and on old drugs with new applications such as mesalazine and ebastine. The antinociceptive effect of linaclotide is now better understood and a meta-analysis has shown its effectiveness in IBS with constipation as the main symptom. In patients with constipation, pelvic floor dysynergy can be diagnosed by a simple clinical interview and rectal touch. More data are available on the efficacy of prucalopride (which has been shown to accelerate

  20. Promoting Motor Function by Exercising the Brain

    Directory of Open Access Journals (Sweden)

    Stephane Perrey

    2013-01-01

    Full Text Available Exercise represents a behavioral intervention that enhances brain health and motor function. The increase in cerebral blood volume in response to physical activity may be responsible for improving brain function. Among the various neuroimaging techniques used to monitor brain hemodynamic response during exercise, functional near-infrared spectroscopy could facilitate the measurement of task-related cortical responses noninvasively and is relatively robust with regard to the subjects’ motion. Although the components of optimal exercise interventions have not been determined, evidence from animal and human studies suggests that aerobic exercise with sufficiently high intensity has neuroprotective properties and promotes motor function. This review provides an insight into the effect of physical activity (based on endurance and resistance exercises on brain function for producing movement. Since most progress in the study of brain function has come from patients with neurological disorders (e.g., stroke and Parkinson’s patients, this review presents some findings emphasizing training paradigms for restoring motor function.

  1. Brushless DC motor Drive during Speed regulation with Current Controller

    Directory of Open Access Journals (Sweden)

    Bhikshalu Manchala

    2015-04-01

    Full Text Available Brushless DC Motor (BLDC is one of the best electrical drives that have increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. Due to the increasing demand for compact & reliable motors and the evolution of low cost power semiconductor switches and permanent magnet (PM materials, brushless DC motors become popular in every application from home appliances to aerospace industry. The conventional techniques for controlling the stator phase current in a brushless DC drive are practically effective in low speed and cannot reduce the commutation torque ripple in high speed range. This paper presents the PI controller for speed control of BLDC motor. The output of the PI controllers is summed and is given as the input to the current controller. The BLDC motor is fed from the inverter where the rotor position and current controller is the input. The complete model of the proposed drive system is developed and simulated using MATLAB/Simulink software. The operation principle of using component is analysed and the simulation results are presented in this to verify the theoretical analysis.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    A.B. Chattopadhyay

    2014-10-01

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

  4. Advanced induction motor drive control with single current sensor

    Directory of Open Access Journals (Sweden)

    Adžić Evgenije M.

    2016-01-01

    Full Text Available This paper proposes induction motor drive control method which uses minimal number of sensors, providing only DC-link current as a feedback signal. Improved DC-link current sampling scheme and modified asymmetrical switching pattern cancels characteristic waveform errors which exist in all three reconstructed motor line-currents. Motor linecurrent harmonic content is reduced to an acceptable level, eliminating torque and speed oscillations which were inherent for conventional single sensor drives. Consequently, use of single current sensor and line-current reconstruction technique is no longer acceptable only for low and medium performance drives, but also for drives where priority is obtaining a highly accurate, stable and fast response. Proposed control algorithm is validated using induction motor drive hardware prototype based on TMS320F2812 digital signal processor. [Projekat Ministarstva nauke Republike Srbije, br. III 042004 and by the Provincial Secretariat for Science and Technological Development of AP Vojvodina under contract No. 114-451-3508/2013-04

  5. Discrete-Time LPV Current Control of an Induction Motor

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    2003-01-01

    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......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...

  6. 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...

  7. 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...... as a set of linear matrix inequalities with full-block multipliers. A standard nonlinear model of the motor is then 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 experimentally on the actual induction motor, both in open-loop current control and when an outer...

  8. 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.

  9. 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...

  10. Current error vector based prediction control of the section winding permanent magnet linear synchronous motor

    Energy Technology Data Exchange (ETDEWEB)

    Hong Junjie, E-mail: hongjjie@mail.sysu.edu.cn [School of Engineering, Sun Yat-Sen University, Guangzhou 510006 (China); Li Liyi, E-mail: liliyi@hit.edu.cn [Dept. Electrical Engineering, Harbin Institute of Technology, Harbin 150000 (China); Zong Zhijian; Liu Zhongtu [School of Engineering, Sun Yat-Sen University, Guangzhou 510006 (China)

    2011-10-15

    Highlights: {yields} The structure of the permanent magnet linear synchronous motor (SW-PMLSM) is new. {yields} A new current control method CEVPC is employed in this motor. {yields} The sectional power supply method is different to the others and effective. {yields} The performance gets worse with voltage and current limitations. - Abstract: To include features such as greater thrust density, higher efficiency without reducing the thrust stability, this paper proposes a section winding permanent magnet linear synchronous motor (SW-PMLSM), whose iron core is continuous, whereas winding is divided. The discrete system model of the motor is derived. With the definition of the current error vector and selection of the value function, the theory of the current error vector based prediction control (CEVPC) for the motor currents is explained clearly. According to the winding section feature, the motion region of the mover is divided into five zones, in which the implementation of the current predictive control method is proposed. Finally, the experimental platform is constructed and experiments are carried out. The results show: the current control effect has good dynamic response, and the thrust on the mover remains constant basically.

  11. 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.

  12. Simultaneous high-definition transcranial direct current stimulation of the motor cortex and motor imagery.

    Science.gov (United States)

    Baxter, Bryan S; Edelman, Bradley; Zhang, Xiaotong; Roy, Abhrajeet; He, Bin

    2014-01-01

    Transcranial direct current stimulation (tDCS) has been used to affect the excitability of neurons within the cerebral cortex. Improvements in motor learning have been found in multiple studies when tDCS was applied to the motor cortex during or before task learning is performed. The application of tDCS to motor imagery, a cognitive task showing activation in similar areas to motor execution, has resulted in differing effects based on the amplitude and duration of stimulation. We utilize high definition tDCS, a more spatially localized version of tDCS, to investigate the effect of anodal stimulation on human motor imagery performance. In parallel, we model this stimulation using a finite element model to calculate stimulation area and electrical field amplitude within the brain in the motor cortex and non-stimulated frontal and parietal regions. Overall, we found a delayed increase in resting baseline power 30 minutes post stimulation in both the right and left sensorimotor cortices which resulted in an increase in event-related desynchronization.

  13. 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.

  14. Respiratory management of motor neurone disease: a review of current practice and new developments.

    Science.gov (United States)

    Rafiq, Muhammad Khizar; Proctor, Alison Ruth; McDermott, Christopher J; Shaw, Pamela J

    2012-06-01

    Motor neurone disease is a neurodegenerative condition with a significant morbidity and shortened life expectancy. Hypoventilatory respiratory failure is the most common cause of death and respiratory function significantly predicts both survival and quality of life in patients with motor neurone disease. Accordingly, supporting and maintaining respiratory function is important in caring for these patients. The most significant advance in motor neurone disease care of recent years has been the domiciliary provision of non-invasive ventilation for treating respiratory failure. Neuromuscular respiratory weakness also leads to ineffective cough and retained airways secretions, predisposing to recurrent chest infections. In this review, we discuss current practice and recent developments in the respiratory management of motor neurone disease, in terms of ventilatory support and cough augmentation.

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

    Directory of Open Access Journals (Sweden)

    K. Baskaran

    2012-01-01

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

  16. Hysteresis Current Control of Switched Reluctance Motor in Aircraft Applications

    Directory of Open Access Journals (Sweden)

    Maged N. F. Nashed

    2014-05-01

    Full Text Available The switched reluctance motor (SRM drives have been widely used in aircraft applications due to the motor advantages like high speed operation, simple construction, no windings on rotor. But high torque ripples and acoustic noise are main disadvantages. The current hysteresis chopping control is one of the important control methods for SRM drives. These disadvantages can be limited using the hysteresis or chopping current control. This control strategy makes the torque of SRM maintained within a set of hysteresis bands by applying suitable source voltage. This paper introduces two hysteresis control modes; hard chopping and soft chopping mode. The SRM drive system is modeled in Simulink model using MATLAB/SIMULINK software package.

  17. Discrete Current Control Strategy of Permanent Magnet Synchronous Motors

    Directory of Open Access Journals (Sweden)

    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.

  18. Motor cortical function and the precision grip.

    Science.gov (United States)

    Geevasinga, Nimeshan; Menon, Parvathi; Kiernan, Matthew C; Vucic, Steve

    2014-12-01

    While task-dependent changes in motor cortical outputs have been previously reported, the issue of whether such changes are specific for complex hand tasks remains unresolved. The aim of the present study was to determine whether cortical inhibitory tone and cortical output were greater during precision grip and power grip. Motor cortex excitability was undertaken by using the transcranial magnetic stimulation threshold tracking technique in 15 healthy subjects. The motor-evoked potential (MEP) responses were recorded over the abductor pollicis brevis (APB), with the hand in the following positions: (1) rest, (2) precision grip and (3) power grip. The MEP amplitude (MEP amplitude REST 23.6 ± 3.3%; MEP amplitude PRECISION GRIP 35.2 ± 5.6%; MEP amplitude POWER GRIP 19.6 ± 3.4%, F = 2.4, P < 0.001) and stimulus-response gradient (SLOPEREST 0.06 ± 0.01; SLOPEPRCISION GRIP 0.15 ± 0.04; SLOPE POWER GRIP 0.07 ± 0.01, P < 0.05) were significantly increased during precision grip. Short interval intracortical inhibition (SICI) was significantly reduced during the precision grip (SICI REST 15.0 ± 2.3%; SICI PRECISION GRIP 9.7 ± 1.5%, SICI POWER GRIP 15.9 ± 2.7%, F = 2.6, P < 0.05). The present study suggests that changes in motor cortex excitability are specific for precision grip, with functional coupling of descending corticospinal pathways controlling thumb and finger movements potentially forming the basis of these cortical changes.

  19. Relationship Between Gross Motor Function and Daily Functional Skill in Children With Cerebral Palsy

    OpenAIRE

    Kwon, Tae Gun; Yi, Sook-Hee; Kim, Tae Won; Chang, Hyun Jung; Kwon, Jeong-Yi

    2013-01-01

    Objective To investigate the relationship between gross motor function and daily functional skill in children with cerebral palsy (CP) and to explore how this relationship is moderated by the Gross Motor Function Classification System, Bimanual Fine Motor Function (BFMF), neuromotor types, and limb distribution of CP. Methods A cross-sectional survey of 112 children with CP (range, 4 years to 7 years and 7 months) was performed. Gross motor function was assessed with the Gross Motor Function ...

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

    Science.gov (United States)

    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…

  1. 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.

  2. 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

  3. 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.

  4. Simplified Modeling, Analysis and Simulation of Permanent Magnet Brushless Direct Current Motors for Sensorless Operation

    Directory of Open Access Journals (Sweden)

    E. Kaliappan

    2012-01-01

    Full Text Available Problem statement: In this study, a simplified modeling and experimental analysis of Permanent Magnet Brushless DC (PMBLDC motors for Sensorless operation using MATLAB/SIMULINK. This model provides a mechanism for monitoring and controlling the voltage, current, speed and torque response. Approach: BLDC motor is modeled as sub-blocks. The inverter and switching function are implemented as S-function builder block. The Sensorless scheme employs direct back emf based zero crossing detection technique. Results: The proposed model with Sensorless control technique with back emf zero crossing detection is tested in the BLDC Motor and the performance was evaluated. The simulated and experimental results show that the proposed modeling works quite well during starting and running conditions. Conclusion/Recommendation: The developed model consists of several independent sub-blocks, that can be used in the modeling of Permanent Magnet Sinusoidal Motor and induction motor. Hence the developed simulation model is a design tool to study the dynamic behavior of Sensorless Controlled Brushless DC Motor.

  5. Enhancing Motor Skill Learning With Transcranial Direct Current Stimulation - A concise review with applications to stroke

    Directory of Open Access Journals (Sweden)

    Sangeetha eMadhavan

    2012-07-01

    Full Text Available In the past few years, there has been a rapid increase in the application of non-invasive brain stimulation to study brain-behavior relations in an effort to potentially increase the effectiveness of neuro-rehabilitation. Transcranial direct current stimulation (tDCS, an emerging technique of non-invasive brain stimulation, has shown to produce beneficial neural effects in consequence with improvements in motor behavior. tDCS has gained popularity as it is economical, simple to use, portable and increases corticospinal excitability without producing any serious side effects. As tDCS has been increasingly investigated as an effective tool for various disorders, numerous improvements and developments have been proposed with respect to this technique. tDCS has been widely used to identify the functional relevance of particular brain regions in motor skill learning and also to facilitate activity in specific cortical areas involved in motor learning, in turn improving motor function. Understanding the interaction between tDCS and motor learning can lead to important implications for developing various rehabilitation approaches. This paper provides a brief overview of tDCS as a neuromodulatory technique and a comprehensive understanding of the interaction of tDCS with motor learning. The paper further briefly goes through the application of this priming technique in the stroke population.

  6. 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

  7. Brushless direct-current motor with stationary armature and field

    Science.gov (United States)

    Studer, P. A.

    1970-01-01

    Electronically commutated dc motor has an active fixed field winding, and active fixed armature winding, and passive rotor. By use of brushless dc motor switching technique, motor provides continuous controllable and reversible torque without use of sliding contacts.

  8. Limb distribution, motor impairment, and functional classification of cerebral palsy

    NARCIS (Netherlands)

    J.A. Gorter; P.L. Rosenbaum

    2004-01-01

    This study explored the relationships between the Gross Motor Function Classification System (GMFCS), limb distribution, and type of motor impairment. Data used were collected in the Ontario Motor Growth study, a longitudinal cohort study with a population-based sample of children with cerebral pals

  9. Apathy, cognitive function and motor function in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Salma S. Soleman Hernandez

    Full Text Available Abstract The aims of this study were to characterize the presence of apathy in patients with AD, determine the relationship between apathy, motor function and cognitive function, and to verify differences among patients stratified by level of apathy in relation to cognitive and motor abilities. Methods: A cross-sectional study was conducted of 37 patients with AD. The following tests were used: MoCA, the Frontal Assessment Battery, Verbal Fluency, Clock Drawing Test, Andreotti & Okuma Battery Tests, Sit and Reach, Resistance of Upper Limbs - AAHPERD Battery Test, Sit and Lift Chair and the Apathy domain of the Neuropsychiatric Inventory. After verifying the normality of the data distribution, comparisons were made using Student's t-test and the U Mann Whitney test; relationships were also assessed using Pearson's and Spearman's correlation coefficients. All analyses were considered to be statistically significant at a p-value of 0.05. Results: 46% of participants in this study showed mild symptoms of apathy. Significant and weak associations were found (p=0.04 between apathy and the attention domain on the MoCA and between apathy and the Walk Test. Analysis of differences in cognitive and motor functions according to participants' level of apathy revealed no significant differences for any of the variables. Conclusion: Apathy was reflected in attention and the Walk Test, suggesting these variables may be related to cognitive and functional decline in AD patients.

  10. 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.

  11. fMRI as a molecular imaging procedure for the functional reorganization of motor systems in chronic stroke

    OpenAIRE

    Lazaridou, Asimina; ASTRAKAS, LOUKAS; Mintzopoulos, Dionyssios; KHANCHICEH, AZADEH; Singhal, Aneesh; Moskowitz, Michael; Rosen, Bruce; Tzika, Aria

    2013-01-01

    Previous brain imaging studies suggest that stroke alters functional connectivity in motor execution networks. Moreover, current understanding of brain plasticity has led to new approaches in stroke rehabilitation. Recent studies showed a significant role of effective coupling of neuronal activity in the SMA (supplementary motor area) and M1 (primary motor cortex) network for motor outcome in patients after stroke. After a subcortical stroke, functional magnetic resonance imaging (fMRI) durin...

  12. 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.

  13. Submerged electricity generation plane with marine current-driven motors

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Classification of current scoring functions.

    Science.gov (United States)

    Liu, Jie; Wang, Renxiao

    2015-03-23

    Scoring functions are a class of computational methods widely applied in structure-based drug design for evaluating protein-ligand interactions. Dozens of scoring functions have been published since the early 1990s. In literature, scoring functions are typically classified as force-field-based, empirical, and knowledge-based. This classification scheme has been quoted for more than a decade and is still repeatedly quoted by some recent publications. Unfortunately, it does not reflect the recent progress in this field. Besides, the naming convention used for describing different types of scoring functions has been somewhat jumbled in literature, which could be confusing for newcomers to this field. Here, we express our viewpoint on an up-to-date classification scheme and appropriate naming convention for current scoring functions. We propose that they can be classified into physics-based methods, empirical scoring functions, knowledge-based potentials, and descriptor-based scoring functions. We also outline the major difference and connections between different categories of scoring functions.

  15. Etiology-specific differences in motor function after hemispherectomy.

    Science.gov (United States)

    van der Kolk, Nicolien M; Boshuisen, Kim; van Empelen, Ron; Koudijs, Suzanne M; Staudt, Martin; van Rijen, Peter C; van Nieuwenhuizen, Onno; Braun, Kees P J

    2013-02-01

    Prediction of functional motor outcome after hemispherectomy is difficult due to the heterogeneity of motor outcomes observed. We hypothesize that this might be related to differences in plasticity during the onset of the underlying epileptogenic disorder or lesion and try to identify predictors of motor outcome after hemispherectomy. Thirty-five children with different etiologies (developmental, stable acquired or progressive) underwent functional hemispherectomy and motor function assessment before hemispherectomy and 24 months after hemispherectomy. Preoperatively, children with developmental etiologies performed better in terms of distal arm strength and hand function, but not on gross motor function tests. Postoperatively, the three etiology groups performed equally poor in muscle strength and hand function, but gross motor function improved in those with acquired and progressive etiologies. Loss of voluntary hand function and distal arm strength after surgery was associated with etiology, intact insular cortex and intact structural integrity of the ipsilesional corticospinal tract on presurgical MRI scans. In conclusion, postoperative motor function can be predicted more precisely based on etiology and on preoperative MRI. Children with developmental etiology more often lose distal arm strength and hand function and show less improvement in gross motor function, compared to those with acquired pathology.

  16. Modeling the Spin Motor Current of the International Space Station's Control Moment Gyroscopes

    Science.gov (United States)

    Pereira, Miguel A.

    2008-01-01

    The International Space Station (ISS) attitude control is provided by two means: The Russian Segment uses thrusters and the U.S. Segment uses double-gimbaled control moment gyroscopes (CMG). CMGs are used as momentum exchange devices, providing non propulsive attitude control for the vehicle. The CMGs are very important for the ISS program because, first, they save propellant - which needs to be transferred to the Station in special cargo vehicles - and, second, they provide the microgravity environment on the Station - which is necessary for scientific experiments planned for the ISS mission. Since 2002, when one of the CMG on the ISS failed, all CMGs are closely monitored. High gimbal rates, vibration spikes, unusual variations of spin motor current and bearing temperatures are of great concern, since these parameters are the CMG health indicators. The telemetry analysis of these and some other CMG parameters is used to determine constrains and make changes to the CMGs operation on board. These CMG limitations, in turn, may limit the ISS attitude control capabilities and may be critical to ISS operation. Therefore, it is important to know whether the CMG parameter is nominal or out of family, and why. The goal of this project is to analyze an important CMG parameter - spin motor current. Some operational decisions are made now based on the spin motor current signatures. The spin motor current depends on gimbal rates, ISS rates, and spin bearing friction. The spin bearing friction in turn depends on the bearing temperatures, wheel rates, normal load - which is a function of gimbal and wheel rates - lubrication, etc. The first task of this project is to create a spin motor current mathematical model based on CMG dynamics model and the current knowledge on bearing friction in microgravity.

  17. Modeling the Spin Motor Current of the International Space Station's Control Moment Gyroscopes

    Science.gov (United States)

    Pereira, Miguel A.

    2008-01-01

    The International Space Station (ISS) attitude control is provided by two means: The Russian Segment uses thrusters and the U.S. Segment uses double-gimbaled control moment gyroscopes (CMG). CMGs are used as momentum exchange devices, providing non propulsive attitude control for the vehicle. The CMGs are very important for the ISS program because, first, they save propellant - which needs to be transferred to the Station in special cargo vehicles - and, second, they provide the microgravity environment on the Station - which is necessary for scientific experiments planned for the ISS mission. Since 2002, when one of the CMG on the ISS failed, all CMGs are closely monitored. High gimbal rates, vibration spikes, unusual variations of spin motor current and bearing temperatures are of great concern, since these parameters are the CMG health indicators. The telemetry analysis of these and some other CMG parameters is used to determine constrains and make changes to the CMGs operation on board. These CMG limitations, in turn, may limit the ISS attitude control capabilities and may be critical to ISS operation. Therefore, it is important to know whether the CMG parameter is nominal or out of family, and why. The goal of this project is to analyze an important CMG parameter - spin motor current. Some operational decisions are made now based on the spin motor current signatures. The spin motor current depends on gimbal rates, ISS rates, and spin bearing friction. The spin bearing friction in turn depends on the bearing temperatures, wheel rates, normal load - which is a function of gimbal and wheel rates - lubrication, etc. The first task of this project is to create a spin motor current mathematical model based on CMG dynamics model and the current knowledge on bearing friction in microgravity.

  18. 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.

  19. 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.

  20. Non-Invasive Electrical Brain Stimulation Montages for Modulation of Human Motor Function.

    Science.gov (United States)

    Curado, Marco; Fritsch, Brita; Reis, Janine

    2016-02-04

    Non-invasive electrical brain stimulation (NEBS) is used to modulate brain function and behavior, both for research and clinical purposes. In particular, NEBS can be applied transcranially either as direct current stimulation (tDCS) or alternating current stimulation (tACS). These stimulation types exert time-, dose- and in the case of tDCS polarity-specific effects on motor function and skill learning in healthy subjects. Lately, tDCS has been used to augment the therapy of motor disabilities in patients with stroke or movement disorders. This article provides a step-by-step protocol for targeting the primary motor cortex with tDCS and transcranial random noise stimulation (tRNS), a specific form of tACS using an electrical current applied randomly within a pre-defined frequency range. The setup of two different stimulation montages is explained. In both montages the emitting electrode (the anode for tDCS) is placed on the primary motor cortex of interest. For unilateral motor cortex stimulation the receiving electrode is placed on the contralateral forehead while for bilateral motor cortex stimulation the receiving electrode is placed on the opposite primary motor cortex. The advantages and disadvantages of each montage for the modulation of cortical excitability and motor function including learning are discussed, as well as safety, tolerability and blinding aspects.

  1. Robotic assessment of upper limb motor function after stroke.

    Science.gov (United States)

    Balasubramanian, Sivakumar; Colombo, Roberto; Sterpi, Irma; Sanguineti, Vittorio; Burdet, Etienne

    2012-11-01

    Traditional assessment of a stroke subject's motor ability, carried out by a therapist who observes and rates the subject's motor behavior using ordinal measurements scales, is subjective, time consuming and lacks sensitivity. Rehabilitation robots, which have been the subject of intense inquiry over the last decade, are equipped with sensors that are used to develop objective measures of motor behaviors in a semiautomated way during therapy. This article reviews the current contributions of robot-assisted motor assessment of the upper limb. It summarizes the various measures related to movement performance, the models of motor recovery in stroke subjects and the relationship of robotic measures to standard clinical measures. It analyses the possibilities offered by current robotic assessment techniques and the aspects to address to make robotic assessment a mainstream motor assessment method.

  2. Children with functional motor limitations : The effects on family strengths

    NARCIS (Netherlands)

    Pirila, S; Van Der Meere, J; Seppanen, RL; Ojala, L; Jaakkola, A; Korpela, R; Nieminen, P

    2005-01-01

    Sixty children with functional motor limitations (age range from 15 months to 7 years 3 months) and their parents participated in the study The objective was to explore the relationship of the severity of their restrictions on family strengths. Functional motor abilities of the children were assesse

  3. 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.

  4. MotomiRs: miRNAs in Motor Neuron Function and Disease

    Directory of Open Access Journals (Sweden)

    Zachary C. E. Hawley

    2017-05-01

    Full Text Available MiRNAs are key regulators of the mammalian transcriptome that have been increasingly linked to degenerative diseases of the motor neurons. Although many of the miRNAs currently incriminated as participants in the pathogenesis of these diseases are also important to the normal development and function of motor neurons, at present there is no knowledge of the complete miRNA profile of motor neurons. In this review, we examine the current understanding with respect to miRNAs that are specifically required for motor neuron development, function and viability, and provide evidence that these should be considered as a functional network of miRNAs which we have collectively termed MotomiRs. We will also summarize those MotomiRs currently known to be associated with both amyotrophic lateral sclerosis (ALS and spinal muscular atrophy (SMA, and discuss their potential use as biomarkers.

  5. Upregulation of cortico-cerebellar functional connectivity after motor learning.

    Science.gov (United States)

    Mehrkanoon, Saeid; Boonstra, Tjeerd W; Breakspear, Michael; Hinder, Mark; Summers, Jeffery J

    2016-03-01

    Interactions between the cerebellum and primary motor cortex are crucial for the acquisition of new motor skills. Recent neuroimaging studies indicate that learning motor skills is associated with subsequent modulation of resting-state functional connectivity in the cerebellar and cerebral cortices. The neuronal processes underlying the motor-learning-induced plasticity are not well understood. Here, we investigate changes in functional connectivity in source-reconstructed electroencephalography (EEG) following the performance of a single session of a dynamic force task in twenty young adults. Source activity was reconstructed in 112 regions of interest (ROIs) and the functional connectivity between all ROIs was estimated using the imaginary part of coherence. Significant changes in resting-state connectivity were assessed using partial least squares (PLS). We found that subjects adapted their motor performance during the training session and showed improved accuracy but with slower movement times. A number of connections were significantly upregulated after motor training, principally involving connections within the cerebellum and between the cerebellum and motor cortex. Increased connectivity was confined to specific frequency ranges in the mu- and beta-bands. Post hoc analysis of the phase spectra of these cerebellar and cortico-cerebellar connections revealed an increased phase lag between motor cortical and cerebellar activity following motor practice. These findings show a reorganization of intrinsic cortico-cerebellar connectivity related to motor adaptation and demonstrate the potential of EEG connectivity analysis in source space to reveal the neuronal processes that underpin neural plasticity.

  6. Bearing Damage Detection of BLDC Motors Based on Current Envelope Analysis

    Science.gov (United States)

    Lee, Chun-Yao; Hsieh, Yu-Hua

    2012-12-01

    This paper proposes current envelope analysis (CEA) to analyze bearing fault signals in brushless direct current (BLDC) motors, and back propagation neural networks (BPNN) to automatically identify bearing faults. We made sample motors which contained different types of fault, recorded the current signals, and extracted the current features using CEA and Hilbert Huang transform (HHT) for BPNN fault identification. The results indicate that this approach can efficiently identify bearing faults in BLDC motors.

  7. Current insights in the development of children’s motor imagery ability

    Directory of Open Access Journals (Sweden)

    Steffie eSpruijt

    2015-06-01

    Full Text Available Over the last two decades, the number of studies on motor imagery in children has witnessed a large expansion. Most studies used the hand laterality judgment paradigm or the mental chronometry paradigm to examine motor imagery ability. The main objective of the current review is to collate these studies to provide a more comprehensive insight in children’s motor imagery development and its age of onset. Motor imagery is a form of motor cognition and aligns with forward (or predictive models of motor control. Studying age-related differences in motor imagery ability in children therefore provides insight in underlying processes of motor development during childhood. Another motivation for studying age-related differences in motor imagery is that in order to effectively apply motor imagery training in children (with motor impairments, it is pertinent to first establish the age at which children are actually able to perform motor imagery.Overall, performance in the imagery tasks develops between 5 and 12 years of age. The age of motor imagery onset, however, remains equivocal, as some studies indicate that children of 5 to 7 years old can already enlist motor imagery in an implicit motor imagery task, whereas other studies using explicit instructions revealed that children do not use motor imagery before the age of 10. From the findings of the current study, we can conclude that motor imagery training is potentially a feasible method for paediatric rehabilitation in children from 5 years on. We suggest that younger children are most likely to benefit from motor imagery training that is presented in an implicit way. Action observation training might be a beneficial adjunct to implicit motor imagery training. From 10 years of age, more explicit forms of motor imagery training can be effectively used.

  8. Cerebellar damage impairs internal predictions for sensory and motor function

    OpenAIRE

    Therrien, Amanda S.; Bastian, Amy J.

    2015-01-01

    The cerebellum is connected to cerebral areas that subserve a range of sensory and motor functions. In this review, we summarize new literature demonstrating deficits in visual perception, proprioception, motor control, and motor learning performance following cerebellar damage. In particular, we highlight novel results that together suggest a general role of the cerebellum in estimating and predicting movement dynamics of the body and environmental stimuli. These findings agree with the hypo...

  9. Motor function in interpolar microtubules during metaphase

    OpenAIRE

    Deutsch, J. M.; Lewis, Ian P.

    2013-01-01

    We analyze experimental observations of microtubules undergoing small fluctuations about a "balance point" when mixed in solution of two different kinesin motor proteins, KLP61F and Ncd. It has been proposed that the microtubule movement is due to stochastic variations in the densities of the two species of motor proteins. We test this hypothesis here by showing how it maps onto a one-dimensional random walk in a random environment. Our estimate of the amplitude of the fluctuations agrees wit...

  10. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation in motor rehabilitation after stroke: an update.

    Science.gov (United States)

    Klomjai, W; Lackmy-Vallée, A; Roche, N; Pradat-Diehl, P; Marchand-Pauvert, V; Katz, R

    2015-09-01

    Stroke is a leading cause of adult motor disability. The number of stroke survivors is increasing in industrialized countries, and despite available treatments used in rehabilitation, the recovery of motor functions after stroke is often incomplete. Studies in the 1980s showed that non-invasive brain stimulation (mainly repetitive transcranial magnetic stimulation [rTMS] and transcranial direct current stimulation [tDCS]) could modulate cortical excitability and induce plasticity in healthy humans. These findings have opened the way to the therapeutic use of the 2 techniques for stroke. The mechanisms underlying the cortical effect of rTMS and tDCS differ. This paper summarizes data obtained in healthy subjects and gives a general review of the use of rTMS and tDCS in stroke patients with altered motor functions. From 1988 to 2012, approximately 1400 publications were devoted to the study of non-invasive brain stimulation in humans. However, for stroke patients with limb motor deficit, only 141 publications have been devoted to the effects of rTMS and 132 to those of tDCS. The Cochrane review devoted to the effects of rTMS found 19 randomized controlled trials involving 588 patients, and that devoted to tDCS found 18 randomized controlled trials involving 450 patients. Without doubt, rTMS and tDCS contribute to physiological and pathophysiological studies in motor control. However, despite the increasing number of studies devoted to the possible therapeutic use of non-invasive brain stimulation to improve motor recovery after stroke, further studies will be necessary to specify their use in rehabilitation.

  11. Brushless DC motor Drive during Speed regulation with Current Controller

    OpenAIRE

    Bhikshalu Manchala; T.Amar Kiran

    2015-01-01

    Brushless DC Motor (BLDC) is one of the best electrical drives that have increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. Due to the increasing demand for compact & reliable motors and the evolution of low cost power semiconductor switches and permanent magnet (PM) materials, brushless DC motors become popular in every application from home appliances to aerospace industry. The conventional techniques for controlling...

  12. Etiology-specific differences in motor function after hemispherectomy

    NARCIS (Netherlands)

    Kolk, N.M. van der; Boshuisen, K.; Empelen, R. van; Koudijs, S.M.; Staudt, M.; Rijen, P.C. van; Nieuwenhuizen, O. van; Braun, K.P.

    2013-01-01

    Prediction of functional motor outcome after hemispherectomy is difficult due to the heterogeneity of motor outcomes observed. We hypothesize that this might be related to differences in plasticity during the onset of the underlying epileptogenic disorder or lesion and try to identify predictors of

  13. Assessment of Motor Development and Function in Preschool Children

    Science.gov (United States)

    Tieman, Beth L.; Palisano, Robert J.; Sutlive, Ann C.

    2005-01-01

    The process of identification of children with delays or disorders in motor development includes developmental screening, examination, and reexamination. Throughout this process, various types of measures are used, including discriminative and evaluative measures. Discriminative and evaluative measures of motor development and function that are…

  14. Motor assessment in pediatric neuropsychology: relationships to executive function.

    Science.gov (United States)

    Shaheen, Sandra

    2013-01-01

    Executive function often refers to control behaviors such as "initiating," "sustaining," "inhibiting," and "switching." These mechanisms contribute to regulation of thinking and emotion but can be observed most clearly in the motor system. Neuropsychology has been influenced by "top-down" models of cognitive control that emerged from information-processing theories of cognition. In fact, neural models provide evidence that control processes are highly interactive within the cortico-striatal-cerebellar circuits. Cognition unfolds in response to motor-driven adaptation, and evidence exists for similar firing of brain cells and circuits during "imagined action" as in actual motor behavior. The motor system develops early and yet is not routinely assessed in neuropsychological evaluation of children with neurodevelopmental disorders. This article reviews some of the approaches to motor assessment that have sensitivity to neurodevelopmental disorders, and advocates for inclusion of motor assessment, particularly in evaluating control processes independent of culture, language, and other confounders.

  15. Inter-individual variability in optimal current direction for transcranial magnetic stimulation of the motor cortex

    DEFF Research Database (Denmark)

    Balslev, Daniela; Braet, Wouter; McAllister, Craig

    2007-01-01

    We evaluated inter-individual variability in optimal current direction for biphasic transcranial magnetic stimulation (TMS) of the motor cortex. Motor threshold for first dorsal interosseus was detected visually at eight coil orientations in 45 degrees increments. Each participant (n=13) completed...... two experimental sessions. One participant with low test-retest correlation (Pearson's rvisual detection of motor threshold was compared to EMG detection; motor thresholds were very similar and highly correlated (0.94-0.99). Similar with previous studies...

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

    Science.gov (United States)

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

    1993-12-01

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

  17. Evaluation of Starting Current of Induction Motors Using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Iman Sadeghkhani

    2014-07-01

    Full Text Available Induction motors (IMs are widely used in industry including it be an electrical or not. However during starting period, their starting currents are so large that can damage equipment. Therefore, this current should be estimated accurately to prevent hazards caused by it. In this paper, the artificial neural network (ANN as an intelligent tool is used to evaluate starting current peak of IMs. Both Multilayer Perceptron (MLP and Radial Basis Function (RBF structures have been analyzed. Six learning algorithms, backpropagation (BP, delta-bar-delta (DBD, extended delta-bar-delta (EDBD, directed random search (DRS, quick propagation (QP, and levenberg marquardt (LM were used to train the MLP. The simulation results using MATLAB show that most developed ANNs can estimate the starting current peak of IMs with good accuracy. However, it is proven that LM and EDBD algorithms present better performance for starting current evaluation based on average of relative and absolute errors.

  18. Treadmill motor current value based walk phase estimation.

    Science.gov (United States)

    Ohki, Eiichi; Nakashima, Yasutaka; Ando, Takeshi; Fujie, Masakatsu G

    2009-01-01

    We have developed a gait rehabilitation robot for hemiplegic patients using the treadmill. A walk phase, which includes time balance of stance and swing legs, is one of the most basic indexes to evaluate patients' gait. In addition, the walking phase is one of the indexes to control our robotic rehabilitation system. However, conventional methods to measure the walk phase require another system such as the foot switch and force plate. In this paper, an original algorithm to estimate the walk phase of a person on a treadmill using only the current value of DC motor to control the treadmill velocity is proposed. This algorithm was verified by experiments on five healthy subjects, and the walk phase of four subjects could be estimated in 0.2 (s) errors. However, the algorithm had erroneously identified a period of time in the stance phase as swing phase time when little body weight loaded on the subject's leg. Because a period of time with little body weight to affected leg is often observed in a hemiplegic walk, the proposed algorithm might fail to properly estimate the walk phase of hemiplegic patients. However, this algorithm could be used to estimate the time when body weight is loaded on patient legs, and thus could be used as a new quantitative evaluation index.

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

    Science.gov (United States)

    Mendoza, Germán; Merchant, Hugo

    2014-11-01

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

  20. Palliative care for patients with motor neurone disease: current challenges

    Directory of Open Access Journals (Sweden)

    Oliver DJ

    2016-05-01

    Full Text Available David J Oliver 1Wisdom Hospice, Rochester, 2University of Kent, Canterbury, UK Abstract: Motor neurone disease is a progressive disease, and the patient and his/her family face many challenges during the disease progression, with increasing weakness and multiple losses of function. The provision of care for these patients and their families is equally challenging, anticipating and responding to the person's needs. There are increasing challenges as more is understood about the disease and its management, including the genetic basis, cognitive change, the use of interventions such as ventilatory support, and gastrostomy. There is also an increasing need to ensure that the later stages are recognized so that all can be more prepared for the end of life, including recognition of deterioration and end of life, advance care planning, symptom management and psychosocial care at the end of life, and coping with requests for assisted dying. Careful assessment and good multidisciplinary team (MDT work can enable patients and their families to have as good a quality of life as possible, and allow a peaceful death of the patient. Keywords: Amyotrophic lateral sclerosis, end of life care, cognitive change, noninvasive ventilation, gastrostomy, advance care planning

  1. Functional Neuroimaging of Motor Control inParkinson’s Disease

    DEFF Research Database (Denmark)

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

    2014-01-01

    and yielded consistent alterations in neural activity in patients with PD. Differences in cortical activation between PD patients and healthy controls converged in a left-lateralized fronto-parietal network comprising the presupplementary motor area, primary motor cortex, inferior parietal cortex......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...

  2. Simulation Research of Fault Model of Detecting Rotor Dynamic Eccentricity in Brushless DC Motor Based on Motor Current Signature Analysis

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Brushless Direct Current (BLDC) motor is widely used in aerospace area, CNC machines and servo systems that require the high control accuracy Once the faults occur in the motor, it will cause great damage to the whole system. Mechanical faults are common in electric machines, and account for up to 50%-60% of the faults. Approximately, 80% of the mechanical faults lead to the eccentricity. So it is necessary to monitor the health condition of the motor to ensure the faults can be detected earlier and measures will be taken to imorove the reliability.

  3. Visual-Motor Maturity and Executive Functions in Schoolchildren

    Directory of Open Access Journals (Sweden)

    Ana Luisa Silva de Oliveira

    2016-08-01

    Full Text Available Abstract Visual-motor maturity and executive functions are closely related in the child development process. This study aimed to investigate the relation between visual-motor abilities and executive functions in 83 healthy children between 7 and 10 years old. The tools used were the Bender Gestalt Visual-Motor Test - Gradual Scoring System (B-GSS, Wisconsin Card Sorting Test (WCST, Raven's Progressive Matrices (RPM, and Rey-Osterrieth Complex Figure (ROCF. The correlation between the B-GSS and WCST scores was significantly negative (r = -.23, p < .033, while ROCF variables, such as Total Memory and Total Copy, had a moderate, significant correlation with total B-GSS score (r = -.55, p < .001; r = -.44, p < .001, respectively. The results empirically show the relation between executive functions and visual-motor maturity and are discussed in face of developmental neuropsychology.

  4. Combining afferent stimulation and mirror therapy for rehabilitating motor function, motor control, ambulation, and daily functions after stroke.

    Science.gov (United States)

    Lin, Keh-chung; Huang, Pai-chuan; Chen, Yu-ting; Wu, Ching-yi; Huang, Wen-ling

    2014-02-01

    Mirror therapy (MT) and mesh glove (MG) afferent stimulation may be effective in reducing motor impairment after stroke. A hybrid intervention of MT combined with MG (MT + MG) may broaden aspects of treatment benefits. To demonstrate the comparative effects of MG + MT, MT, and a control treatment (CT) on the outcomes of motor impairments, manual dexterity, ambulation function, motor control, and daily function. Forty-three chronic stroke patients with mild to moderate upper extremity impairment were randomly assigned to receive MT + MG, MT, or CT for 1.5 hours/day, 5 days/week for 4 weeks. Outcome measures were the Fugl-Meyer Assessment (FMA) and muscle tone measured by Myoton-3 for motor impairment and the Box and Block Test (BBT) and 10-Meter Walk Test (10 MWT) for motor function. Secondary outcomes included kinematic parameters for motor control and the Motor Activity Log and ABILHAND Questionnaire for daily function. FMA total scores were significantly higher and synergistic shoulder abduction during reach was less in the MT + MG and MT groups compared with the CT group. Performance on the BBT and the 10 MWT (velocity and stride length in self-paced task and velocity in as-quickly-as-possible task) were improved after MT + MG compared with MT. MT + MG improved manual dexterity and ambulation. MT + MG and MT reduced motor impairment and synergistic shoulder abduction more than CT. Future studies may integrate functional task practice into treatments to enhance functional outcomes in patients with various levels of motor severity. The long-term effects of MG + MT remain to be evaluated.

  5. 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.

  6. Transcranial direct current stimulation is not effective in the motor strength and gait recovery following motor incomplete spinal cord injury during Lokomat(®) gait training.

    Science.gov (United States)

    Kumru, Hatice; Murillo, Narda; Benito-Penalva, Jesus; Tormos, Jose M; Vidal, Joan

    2016-05-04

    Transcranial direct current stimulation (tDCS) is a potential tool to improve motor recovery in patients with neurological disorders. Safety and efficacy of this procedure for lower extremity motor strengthe and gait function in motor incomplete spinal cord injury (SCI) have not yet been addressed. The aim of this study is to optimize the functional outcome in early phases of gait rehabilitation assisted by Lokomat(®) in motor incomplete SCI patients using tDCS as an additional treatment to physical therapy. We performed in a SCI unit a single-centre randomized, double-blind, sham-controlled study to investigate safety and efficacy of anodal tDCS of over leg motor cortex in motor incomplete SCI patients. Twenty-four SCI patients received either daily sessions of anodal tDCS (n=12) at 2mA for 20min to the vertex (leg motor cortex) during twenty days or sham tDCS (n=12). Motor deficit was assessed by the lower extremity motor score (LEMS) and for gait function: ten meter walking test (10MWT) and Walking Index for SCI (WISCI II) at baseline, after last tDCS session (after 4 weeks of stimulation), and after 8 weeks (from baseline) for follow-up. No side effects were detected during either tDCS or sham. In both groups, there was a significant improvement in LEMS (p<0.03), which did not significantly differ when comparing anodal and sham tDCS groups. During follow-up, in both group 5 of 12 patients could perform gait, without significant differences in gait velocity, cadence, step length and WISCI-II between both groups. Combination twenty sessions of daily tDCS to the leg motor cortex and Lokomat(®) gait training appear to be safe in motor incomplete SCI patients. There was an expected improvement in both LEMS and gait scales however, did not differ between patients treated with anodal or sham tDCS. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Functional MRI imaging in localizing motor paradigm

    OpenAIRE

    Tavares, Oscar

    2014-01-01

    Objetivos – Um dos principais objetivos da neurociência tem sido, desde sempre, compreender as funcionalidades do cérebro. A introdução da ressonância magnética funcional contribuiu em grande escala para o desenvolvimento do estudo cerebral. Assim, esta investigação tem como principal objetivo identificar e desenhar os diferentes perfis de localizações cerebrais, a nível do córtex motor, numa população jovem saudável, permitindo, assim, um maior conhecimento nesta área e dando um contribut...

  10. Methylphenidate improves motor functions in children diagnosed with Hyperkinetic Disorder

    Science.gov (United States)

    Stray, Liv Larsen; Stray, Torstein; Iversen, Synnøve; Ruud, Anne; Ellertsen, Bjørn

    2009-01-01

    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. PMID:19439096

  11. 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.

  12. Functional motor microdomains of the outer hair cell lateral membrane.

    Science.gov (United States)

    Santos-Sacchi, Joseph

    2002-12-01

    The outer hair cell (OHC) of the mammalian inner ear is a highly partitioned neuroepithelial cell whose lateral membrane is devoted to electromotility, a fast mechanical length change owing to the motor protein, prestin. Spatially restricted measures of prestin-derived nonlinear capacitance or gating charge, using either electrical amputation or discrete membrane mechanical deformation, were used to determine that functional variation exists within the extensive lateral membrane of the cell. This was evidenced by variation in the motor's operating voltage range and sensitivity among microdomains within the lateral membrane. That is, localized regions of the membrane evidenced Boltzmann distributions of motor charge whose midpoint voltage and slope differed from those obtained for the whole cell. These data highlight the functional independence of microdomains and imply that measured whole cell characteristics may differ from the microscopic characteristics of elementary motors.

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

    Science.gov (United States)

    Carmel, Jason B; Martin, John H

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Jason B Carmel

    2014-06-01

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

  15. Functional Plasticity in Somatosensory Cortex Supports Motor Learning by Observing.

    Science.gov (United States)

    McGregor, Heather R; Cashaback, Joshua G A; Gribble, Paul L

    2016-04-04

    An influential idea in neuroscience is that the sensory-motor system is activated when observing the actions of others [1, 2]. This idea has recently been extended to motor learning, in which observation results in sensory-motor plasticity and behavioral changes in both motor and somatosensory domains [3-9]. However, it is unclear how the brain maps visual information onto motor circuits for learning. Here we test the idea that the somatosensory system, and specifically primary somatosensory cortex (S1), plays a role in motor learning by observing. In experiment 1, we applied stimulation to the median nerve to occupy the somatosensory system with unrelated inputs while participants observed a tutor learning to reach in a force field. Stimulation disrupted motor learning by observing in a limb-specific manner. Stimulation delivered to the right arm (the same arm used by the tutor) disrupted learning, whereas left arm stimulation did not. This is consistent with the idea that a somatosensory representation of the observed effector must be available during observation for learning to occur. In experiment 2, we assessed S1 cortical processing before and after observation by measuring somatosensory evoked potentials (SEPs) associated with median nerve stimulation. SEP amplitudes increased only for participants who observed learning. Moreover, SEPs increased more for participants who exhibited greater motor learning following observation. Taken together, these findings support the idea that motor learning by observing relies on functional plasticity in S1. We propose that visual signals about the movements of others are mapped onto motor circuits for learning via the somatosensory system.

  16. How transcranial direct current stimulation can modulate implicit motor sequence learning and consolidation: A brief review

    Directory of Open Access Journals (Sweden)

    Branislav eSavic

    2016-02-01

    Full Text Available The purpose of this review is to investigate how transcranial direct current stimulation (tDCS can modulate implicit motor sequence learning and consolidation. So far, most of the studies have focused on the modulating effect of tDCS for explicit motor learning. Here, we focus explicitly on implicit motor sequence learning and consolidation in order to improve our understanding about the potential of tDCS to affect this kind of unconscious learning. Specifically, we concentrate on studies with the serial reaction time task (SRTT, the classical paradigm for measuring implicit motor sequence learning. The influence of tDCS has been investigated for the primary motor cortex, the premotor cortex, the prefrontal cortex, and the cerebellum. The results indicate that tDCS above the primary motor cortex gives raise to the most consistent modulating effects for both implicit motor sequence learning and consolidation.

  17. DSPIC BASED POWER ASSISTED STEERING USING BRUSHLESS DIRECT CURRENT MOTOR

    Directory of Open Access Journals (Sweden)

    G. R.P. Lakshmi

    2013-01-01

    Full Text Available This study illustrates the Electrically Assisted power Steering (EAS using BLDC motor for a vehicle. Earlier the Electrically Assisted power Steering (EAS was implemented with DSP. This study shows the usage of a dsPIC to control the BLDC motor with an encoder. The BLDC motor here is driven by dsPIC through a three phase inverter system. IRAMS type of inverter is used which is cost efficient and space efficient. The dsPIC supplied with the input of the steering. In its higher capacity the vehicles speed controller acts as the assistance level controller for steering effort. At the lower capacity, the torque controller gives the effort level control. In reality this can be realized as torque sensor and vehicle sensor interfaced in the dsPIC. For actual implementation in the system, a dsPIC-based BLDC motor controller with three-phase inverter module is used with Hall-effect sensor feedback. It is designed in such a way that the driver assistance can be varied at any time without any difficulty.

  18. [Motor coordination function of attention deficit hyperactivity disorder (review)].

    Science.gov (United States)

    Feng, Lei; Cheng, Jia; Wang, Yu-feng

    2007-06-18

    Attention deficit hyperactivity disorder (ADHD) and developmental coordination disorder (DCD) are both childhood disorders identified in the DSM-IV. Studies investigating ADHD have found that around half of ADHD cases also have motor problems severe enough to be diagnosed as DCD. Further, children initially diagnosed as DCD have also been found to meet moderate to severe diagnosis for ADHD. Both disorders have been linked to a lot of psychosocial problems. Furthermore, when ADHD and DCD are co-morbid, the outcome tends to be more severe than when either disorder occurs alone. In the past decade, many studies identified shown that ADHD children experienced difficulties with both fine motor movements and gross motor movements. Notably, most of these foregoing studies found balance functions of ADHD were impaired. In order to maintain balance under a verity of environmental conditions, sensory information from somatosensory, visual, and vestibular origins must be integrated by the central nervous system. But there are rich evidences suggesting that children with ADHD can not organize the motor information effectively. The maintenance and control of posture and balance, whether in static or dynamic conditions, are essential requirements for daily activity. The balance function has been closely associated not only with both gross motor movements, such as sitting, standing, walking and fine motor movements, but also with human behaviors. There are increasing evidences suggesting that balance deficit correlates with symptoms of ADHD. Therefore, motor coordination difficulties co-occurring with ADHD should be given emphasis in clinical practice; the training of balance may be one of the possible methods to improve the motor coordination function in ADHD children.

  19. Haptic fMRI: combining functional neuroimaging with haptics for studying the brain's motor control representation.

    Science.gov (United States)

    Menon, Samir; Brantner, Gerald; Aholt, Chris; Kay, Kendrick; Khatib, Oussama

    2013-01-01

    A challenging problem in motor control neuroimaging studies is the inability to perform complex human motor tasks given the Magnetic Resonance Imaging (MRI) scanner's disruptive magnetic fields and confined workspace. In this paper, we propose a novel experimental platform that combines Functional MRI (fMRI) neuroimaging, haptic virtual simulation environments, and an fMRI-compatible haptic device for real-time haptic interaction across the scanner workspace (above torso ∼ .65×.40×.20m(3)). We implement this Haptic fMRI platform with a novel haptic device, the Haptic fMRI Interface (HFI), and demonstrate its suitability for motor neuroimaging studies. HFI has three degrees-of-freedom (DOF), uses electromagnetic motors to enable high-fidelity haptic rendering (>350Hz), integrates radio frequency (RF) shields to prevent electromagnetic interference with fMRI (temporal SNR >100), and is kinematically designed to minimize currents induced by the MRI scanner's magnetic field during motor displacement (Tesla fMRI scanner's baseline noise variation (∼.85±.1%). Finally, HFI is haptically transparent and does not interfere with human motor tasks (tested for .4m reaches). By allowing fMRI experiments involving complex three-dimensional manipulation with haptic interaction, Haptic fMRI enables-for the first time-non-invasive neuroscience experiments involving interactive motor tasks, object manipulation, tactile perception, and visuo-motor integration.

  20. Rebuilding motor function of the spinal cord based on functional electrical stimulation.

    Science.gov (United States)

    Shen, Xiao-Yan; Du, Wei; Huang, Wei; Chen, Yi

    2016-08-01

    Rebuilding the damaged motor function caused by spinal cord injury is one of the most serious challenges in clinical neuroscience. The function of the neural pathway under the damaged sites can be rebuilt using functional electrical stimulation technology. In this study, the locations of motor function sites in the lumbosacral spinal cord were determined with functional electrical stimulation technology. A three-dimensional map of the lumbosacral spinal cord comprising the relationship between the motor function sites and the corresponding muscle was drawn. Based on the individual experimental parameters and normalized coordinates of the motor function sites, the motor function sites that control a certain muscle were calculated. Phasing pulse sequences were delivered to the determined motor function sites in the spinal cord and hip extension, hip flexion, ankle plantarflexion, and ankle dorsiflexion movements were successfully achieved. The results show that the map of the spinal cord motor function sites was valid. This map can provide guidance for the selection of electrical stimulation sites during the rebuilding of motor function after spinal cord injury.

  1. Rebuilding motor function of the spinal cord based on functional electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    Xiao-yan Shen; Wei Du; Wei Huang; Yi Chen

    2016-01-01

    Rebuilding the damaged motor function caused by spinal cord injury is one of the most serious challenges in clinical neuroscience. The function of the neural pathway under the damaged sites can be rebuilt using functional electrical stimulation technology. In this study, the locations of motor function sites in the lumbosacral spinal cord were determined with functional electrical stimulation technology. A three-dimensional map of the lumbosacral spinal cord comprising the relationship between the motor function sites and the correspond-ing muscle was drawn. Based on the individual experimental parameters and normalized coordinates of the motor function sites, the motor function sites that control a certain muscle were calculated. Phasing pulse sequences were delivered to the determined motor function sites in the spinal cord and hip extension, hip lfexion, ankle plantarlfexion, and ankle dorsilfexion movements were successfully achieved. The results show that the map of the spinal cord motor function sites was valid. This map can provide guidance for the selection of electrical stimulation sites during the rebuilding of motor function after spinal cord injury.

  2. Ocular Motor Function in Patients with Bilateral Vestibular Weakness

    Directory of Open Access Journals (Sweden)

    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.

  3. 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.

  4. Cheaper Synthesis Of Multipole-Brushless-dc-Motor Current

    Science.gov (United States)

    Alhorn, Dean C.; Howard, David E.

    1994-01-01

    Circuit converts output of single two-phase shaft-angle resolver to that of multi-speed three-phase shaft-angle resolver. Converter circuit applicable to generation of multispeed, multiphase shaft-angle-resolver signals from single two-phase shaft-angle resolver. Combination of converter circuit and single two-phase shaft-angle resolver offer advantages in cost, weight, size, and complexity. Design readily adaptable to two-phase motor.

  5. Fault detection and diagnosis of induction motors using motor current signature analysis and a hybrid FMM-CART model.

    Science.gov (United States)

    Seera, Manjeevan; Lim, Chee Peng; Ishak, Dahaman; Singh, Harapajan

    2012-01-01

    In this paper, a novel approach to detect and classify comprehensive fault conditions of induction motors using a hybrid fuzzy min-max (FMM) neural network and classification and regression tree (CART) is proposed. The hybrid model, known as FMM-CART, exploits the advantages of both FMM and CART for undertaking data classification and rule extraction problems. A series of real experiments is conducted, whereby the motor current signature analysis method is applied to form a database comprising stator current signatures under different motor conditions. The signal harmonics from the power spectral density are extracted as discriminative input features for fault detection and classification with FMM-CART. A comprehensive list of induction motor fault conditions, viz., broken rotor bars, unbalanced voltages, stator winding faults, and eccentricity problems, has been successfully classified using FMM-CART with good accuracy rates. The results are comparable, if not better, than those reported in the literature. Useful explanatory rules in the form of a decision tree are also elicited from FMM-CART to analyze and understand different fault conditions of induction motors.

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

    Science.gov (United States)

    Park, Myoung-Ok

    2017-02-01

    [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 Systems, and manual function was measured using the Manual Ability Classification System. [Results] Motor skills in daily activities were significantly different on Gross Motor Function Classification System level and Manual Ability Classification System level. According to the results of multiple regression analysis, children categorized as Gross Motor Function Classification System level III scored lower in terms of performance based motor skills than Gross Motor Function Classification System level I children. Also, when analyzed with respect to Manual Ability Classification System level, level II was lower than level I, and level III was lower than level II in terms of performance based motor skills. [Conclusion] The results of this study indicate that performance-based motor skills differ among children categorized based on Gross Motor Function Classification System and Manual Ability Classification System levels of cerebral palsy.

  7. 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.

  8. The effect of anodal transcranial direct current stimulation on spatial motor skill learning in healthy and spinal cord injured humans

    OpenAIRE

    Ashworth-Beaumont, Jim

    2012-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Anodal transcranial direct current stimulation (tDCS) is an intervention which is thought to enhance motor learning in healthy and stroke-injured states, when applied adjunctively during skill learning. We set out to investigate whether anodal tDCS might enhance functional rehabilitation from incomplete tetraplegic SCI. To address current limitations in the measurement of task-dependent skill...

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

    Science.gov (United States)

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

    2016-11-01

    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.

  10. Structural Equation Modeling of Motor Impairment, Gross Motor Function, and the Functional Outcome in Children with Cerebral Palsy

    Science.gov (United States)

    Park, Eun-Young; Kim, Won-Ho

    2013-01-01

    Physical therapy intervention for children with cerebral palsy (CP) is focused on reducing neurological impairments, improving strength, and preventing the development of secondary impairments in order to improve functional outcomes. However, relationship between motor impairments and functional outcome has not been proved definitely. This study…

  11. Analysis of torque-current characteristic of brushless DC motor driven by three-phase H-bridge

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Presents the simulation and analysis of the steady state characteristic of a brushless DC motor studies the torque-current characteristic of the motor as well and discusses the design of a current-measure circuit for torque controlling.

  12. A Study on New Current Controller for 7-Phase BLDC Motor Drive System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Surk; Jeon, Ywun Seok; Mok, Hyung Soo [Konkuk University (Korea); Kim, Duk Keun [Komotek Co., Ltd. (Korea)

    2001-04-01

    Recently, the demand of motor for industrial, household machinery is increasing. As Switching devices and control technology are progressing, so the use of BLDC Motor is increasing. But 3-phase BLCD Motor generally used has pulsating torque and speed variation in commutation, so the range of its application is limited to high speed operation. Especially, to solve these problems, it is necessary to increase phase of Motor, so study of Poly-Phase BLDC Motor is progressing. However, when hysteresis current controller is used, switching frequency is highly increasing. In this paper, 7-Phase BLDC Motor drive system is designed. Also MSTC (Minimum Switching Time Controller) is proposed and with simulation and experiment, their validities are verified. (author). 10 refs., 26 figs., 1 tab.

  13. Motor preparation, motor execution, attention, and executive functions in attention deficit/hyperactivity disorder (ADHD).

    Science.gov (United States)

    Klimkeit, Ester I; Mattingley, Jason B; Sheppard, Dianne M; Lee, Paul; Bradshaw, John L

    2005-04-01

    Attention and executive functions were investigated in medicated and unmedicated children with ADHD combined type using a novel selective reaching task. This task involved responding as rapidly as possible to a target while at times having to ignore a distractor. Results indicated that unmedicated children with ADHD showed slow and inaccurate responding. Slow responding reflected problems at the stage of movement preparation but not movement execution. An attentional impairment, rather than a motor planning problem per se, appeared to underlie the slow movement preparation. Inaccurate responding reflected problems with response inhibition and selective attention, impulsivity, set-shifting, and difficulties in maintaining vigilance. Although medicated children with ADHD did not show slow movement preparation, they did show some response inaccuracy, resulting especially from impulsive responding. These findings suggest that ADHD is characterized by slow motor preparation (but not motor execution), and deficits in selective attention, vigilance, and executive functions. Preliminary results suggest that stimulant medication may resolve some of these motor, attentional and executive function deficits.

  14. Effect of motor relearning programme on motor function recovery of acute stroke patients with hemiplegia

    Directory of Open Access Journals (Sweden)

    Min GUAN

    2017-03-01

    Full Text Available Objective To explore the effect of motor relearning programme (MRP on motor function recovery of patients with hemiplegia after acute stroke.  Methods A total of 64 hemiplegic patients with acute stroke (duration ≤ 14 d were randomly divided into 2 groups: control group (N = 32 and observation group (N = 32. Control group received routine drug therapy and conventional rehabilitation training, and observation group was treated by routine therapy and MRP training. Fugl-Meyer Assessment Scale - Balance (FMA - Balance, Modified Rivermead Mobility Index (MRMI and modified Barthel Index (mBI were used to assess the motor function of patients in both groups before and after treatment.  Results All patients successfully completed the rehabilitation training without severe adverse events. A few patients felt fatigue occasionally after training and recovered after rest. Compared to before treatment, the FMA-Balance score (P = 0.000, MRMI score (P = 0.000 and mBI score (P = 0.000 after treatment in both groups were significantly increased. Compared to control group, the FMA-Balance score (P = 0.031, MRMI score (P = 0.013 and mBI score (P = 0.049 after treatment in observation group were significantly increased.  Conclusions MRP training in the early stage of stroke is beneficial to the recovery of motor function of patients. DOI: 10.3969/j.issn.1672-6731.2017.03.007

  15. Different current intensities of anodal transcranial direct current stimulation do not differentially modulate motor cortex plasticity.

    Science.gov (United States)

    Kidgell, Dawson J; Daly, Robin M; Young, Kayleigh; Lum, Jarrod; Tooley, Gregory; Jaberzadeh, Shapour; Zoghi, Maryam; Pearce, Alan J

    2013-01-01

    Transcranial direct current stimulation (tDCS) is a noninvasive technique that modulates the excitability of neurons within the motor cortex (M1). Although the aftereffects of anodal tDCS on modulating cortical excitability have been described, there is limited data describing the outcomes of different tDCS intensities on intracortical circuits. To further elucidate the mechanisms underlying the aftereffects of M1 excitability following anodal tDCS, we used transcranial magnetic stimulation (TMS) to examine the effect of different intensities on cortical excitability and short-interval intracortical inhibition (SICI). Using a randomized, counterbalanced, crossover design, with a one-week wash-out period, 14 participants (6 females and 8 males, 22-45 years) were exposed to 10 minutes of anodal tDCS at 0.8, 1.0, and 1.2 mA. TMS was used to measure M1 excitability and SICI of the contralateral wrist extensor muscle at baseline, immediately after and 15 and 30 minutes following cessation of anodal tDCS. Cortical excitability increased, whilst SICI was reduced at all time points following anodal tDCS. Interestingly, there were no differences between the three intensities of anodal tDCS on modulating cortical excitability or SICI. These results suggest that the aftereffect of anodal tDCS on facilitating cortical excitability is due to the modulation of synaptic mechanisms associated with long-term potentiation and is not influenced by different tDCS intensities.

  16. Different Current Intensities of Anodal Transcranial Direct Current Stimulation Do Not Differentially Modulate Motor Cortex Plasticity

    Directory of Open Access Journals (Sweden)

    Dawson J. Kidgell

    2013-01-01

    Full Text Available Transcranial direct current stimulation (tDCS is a noninvasive technique that modulates the excitability of neurons within the motor cortex (M1. Although the aftereffects of anodal tDCS on modulating cortical excitability have been described, there is limited data describing the outcomes of different tDCS intensities on intracortical circuits. To further elucidate the mechanisms underlying the aftereffects of M1 excitability following anodal tDCS, we used transcranial magnetic stimulation (TMS to examine the effect of different intensities on cortical excitability and short-interval intracortical inhibition (SICI. Using a randomized, counterbalanced, crossover design, with a one-week wash-out period, 14 participants (6 females and 8 males, 22–45 years were exposed to 10 minutes of anodal tDCS at 0.8, 1.0, and 1.2 mA. TMS was used to measure M1 excitability and SICI of the contralateral wrist extensor muscle at baseline, immediately after and 15 and 30 minutes following cessation of anodal tDCS. Cortical excitability increased, whilst SICI was reduced at all time points following anodal tDCS. Interestingly, there were no differences between the three intensities of anodal tDCS on modulating cortical excitability or SICI. These results suggest that the aftereffect of anodal tDCS on facilitating cortical excitability is due to the modulation of synaptic mechanisms associated with long-term potentiation and is not influenced by different tDCS intensities.

  17. On-line tool breakage monitoring of vibration tapping using spindle motor current

    Science.gov (United States)

    Li, Guangjun; Lu, Huimin; Liu, Gang

    2008-10-01

    Input current of driving motor has been employed successfully as monitoring the cutting state in manufacturing processes for more than a decade. In vibration tapping, however, the method of on-line monitoring motor electric current has not been reported. In this paper, a tap failure prediction method is proposed to monitor the vibration tapping process using the electrical current signal of the spindle motor. The process of vibration tapping is firstly described. Then the relationship between the torque of vibration tapping and the electric current of motor is investigated by theoretic deducing and experimental measurement. According to those results, a monitoring method of tool's breakage is proposed through monitoring the ratio of the current amplitudes during adjacent vibration tapping periods. Finally, a low frequency vibration tapping system with motor current monitoring is built up using a servo motor B-106B and its driver CR06. The proposed method has been demonstrated with experiment data of vibration tapping in titanic alloys. The result of experiments shows that the method, which can avoid the tool breakage and giving a few error alarms when the threshold of amplitude ratio is 1.2 and there is at least 2 times overrun among 50 adjacent periods, is feasible for tool breakage monitoring in the process of vibration tapping small thread holes.

  18. Rubriek 'Meten in de praktijk': Gross Motor Function Measure.

    NARCIS (Netherlands)

    Veenhof, C.; Ketelaar, M.

    2004-01-01

    De Gross Motor Function Measure (GMFM) is een instrument dat de grof-motorische vaardigheden meet van kinderen met cerebrale parese. De GMFM is expliciet ontwikkeld als evaluatief meetinstrument, wat betekent dat het bedoeld is om veranderingen over de tijd of verandering en die optreden na behandel

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

    Science.gov (United States)

    Morris, Christopher

    2008-01-01

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

  20. Why do stroke patients with negative motor evoked potential show poor limb motor function recovery?*

    Institute of Scientific and Technical Information of China (English)

    Zhibin Song; Lijuan Dang; Yanling Zhou; Yanjiang Dong; Haimao Liang; Zhengfeng Zhu; Suyue Pan

    2013-01-01

    Negative motor evoked potentials after cerebral infarction, indicative of poor recovery of limb motor function, tend to be accompanied by changes in fractional anisotropy values and the cerebral pe-duncle area on the affected side, but the characteristics of these changes have not been reported. This study included 57 cases of cerebral infarction whose motor evoked potentials were tested in the 24 hours after the first inspection for diffusion tensor imaging, in which 29 cases were in the negative group and 28 cases in the positive group. Twenty-nine patients with negative motor evoked potentials were divided into two groups according to fractional anisotropy on the affected side of the cerebral peduncle: a fractional anisotropy < 0.36 group and a fractional anisotropy ≥ 0.36 group. Al patients underwent a regular magnetic resonance imaging and a diffusion tensor imaging examina-tion at 1 week, 1, 3, 6 and 12 months after cerebral infarction. The Fugl-Meyer scores of their he-miplegic limbs were tested before the magnetic resonance and diffusion tensor imaging tions. In the negative motor evoked potential group, fractional anisotropy in the affected cerebral peduncle declined progressively, which was most obvious in the first 1-3 months after the onset of cerebral infarction. The areas and area asymmetries of the cerebral peduncle on the affected side were significantly decreased at 6 and 12 months after onset. At 12 months after onset, the area asymmetries of the cerebral peduncle on the affected side were lower than the normal lower limit value of 0.83. Fugl-Meyer scores in the fractional anisotropy ≥ 0.36 group were significantly higher than in the fractional anisotropy < 0.36 group at 3-12 months after onset. The fractional anisotropy of the cerebral peduncle in the positive motor evoked potential group decreased in the first 1 month after onset, and stayed unchanged from 3-12 months; there was no change in the area of the ce-rebral peduncle in the first 1

  1. 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

  2. Trains of transcranial direct current stimulation antagonize motor cortex hypoexcitability induced by acute hemicerebellectomy.

    Science.gov (United States)

    Ben Taib, Nordeyn Oulad; Manto, Mario

    2009-10-01

    The cerebellum is a key modulator of motor cortex activity, allowing both the maintenance and fine-tuning of motor cortex discharges. One elemental defect associated with acute cerebellar lesions is decreased excitability of the contralateral motor cortex, which is assumed to participate in deficits in skilled movements and considered a major defect in motor cortex properties. In the present study, the authors assessed the effect of trains of anodal transcranial direct current stimulation (tDCS), which elicits polarity-dependent shifts in resting membrane potentials. Transcranial DCS countered the defect in motor cortex excitability contralaterally to the hemicerebellar ablation. The depression of both the H-reflex and F wave remained unchanged with tDCS, and cutaneomuscular reflexes remained unaffected. Transcranial DCS antagonized motor cortex hypoexcitability induced by high-frequency stimulation of interpositus nucleus. The authors' results show that tDCS has the potential to modulate motor cortex excitability after acute cerebellar dysfunction. By putting the motor cortex at the appropriate level of excitability, tDCS might allow the motor cortex to become more reactive to the procedures of training or learning.

  3. A transient energy function for power systems including the induction motor model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A construction method for power system transient energy function is studied in the paper, which is simple and universal, and can unify the forms of some current energy functions. A transient energy function including the induction motor model is derived using the method. The unintegrable term is dealt with to get an approximate energy function. Simulations in a 3-bus system and in the WSCC 4-generator system verify the validity of the proposed energy function. The function can be applied to direct transient stability analysis of multi-machine large power systems and provides a tool for analysis of the interaction between the generator angle stability and the load voltage stability.

  4. The Motor Function Neurological Assessment (MFNU) as an indicator of motor function problems in boys with ADHD

    Science.gov (United States)

    Stray, Liv Larsen; Stray, Torstein; Iversen, Synnøve; Ruud, Anne; Ellertsen, Bjørn; Tønnessen, Finn Egil

    2009-01-01

    Background The paper presents the Motor Function Neurological Assessment (MFNU), as a tool for identifying typical motor function problems in children with Attention Deficit Hyperactivity Disorder (ADHD). The study investigated motor functions in boys diagnosed with Hyperkinetic Disorder (HKD, F.90.0). HKD corresponds to the ADHD-combined (ADHD-C) diagnosis in the DSM-IV. The paper addresses the ability of the instrument to discriminate between non-medicated boys with HKD and a control group consisting of normal non-referred boys without any clinical significant ADHD symptoms. Methods 25 drug-naïve boys, aged 8–12 years and recently diagnosed as HKD F90.0, were compared with 27 controls, all boys in the same age range, on 17 MFNU subtests, and with a 'Total score' parameter. Results On the individual subtests 80–96% (median 88%) of the ADHD group showed 'moderate' to 'severe' problems, compared to 0–44% (median 14.8%) within the control group. The percentage of 'severe problems' ranged from 44–84%, (median 64%) in the ADHD group, and 0–44% (median 0%) in the control group. The highly significant differences found between the groups on all subtests, and on the Total score scores, indicated that the MFNU had a high discriminative power when children with ADHD and normal controls were compared. The Total score parameter seemed to be a meaningful discriminator of a common underlying factor of the 17 subtests used in the study. Conclusion The study confirms our clinical findings that the MFNU measures a consistent pattern of motor function problems in children with HKD, and that these problems are rarely represented in individuals without ADHD. Further research is needed to investigate to what extent the MFNU taps motor problems that are truly specific to ADHD, in contrast to motor problems common to children with DCD or other clinical problems. PMID:19450246

  5. The Motor Function Neurological Assessment (MFNU as an indicator of motor function problems in boys with ADHD

    Directory of Open Access Journals (Sweden)

    Iversen Synnøve

    2009-05-01

    Full Text Available Abstract Background The paper presents the Motor Function Neurological Assessment (MFNU, as a tool for identifying typical motor function problems in children with Attention Deficit Hyperactivity Disorder (ADHD. The study investigated motor functions in boys diagnosed with Hyperkinetic Disorder (HKD, F.90.0. HKD corresponds to the ADHD-combined (ADHD-C diagnosis in the DSM-IV. The paper addresses the ability of the instrument to discriminate between non-medicated boys with HKD and a control group consisting of normal non-referred boys without any clinical significant ADHD symptoms. Methods 25 drug-naïve boys, aged 8–12 years and recently diagnosed as HKD F90.0, were compared with 27 controls, all boys in the same age range, on 17 MFNU subtests, and with a 'Total score' parameter. Results On the individual subtests 80–96% (median 88% of the ADHD group showed 'moderate' to 'severe' problems, compared to 0–44% (median 14.8% within the control group. The percentage of 'severe problems' ranged from 44–84%, (median 64% in the ADHD group, and 0–44% (median 0% in the control group. The highly significant differences found between the groups on all subtests, and on the Total score scores, indicated that the MFNU had a high discriminative power when children with ADHD and normal controls were compared. The Total score parameter seemed to be a meaningful discriminator of a common underlying factor of the 17 subtests used in the study. Conclusion The study confirms our clinical findings that the MFNU measures a consistent pattern of motor function problems in children with HKD, and that these problems are rarely represented in individuals without ADHD. Further research is needed to investigate to what extent the MFNU taps motor problems that are truly specific to ADHD, in contrast to motor problems common to children with DCD or other clinical problems.

  6. Cargo binding activates myosin VIIA motor function in cells.

    Science.gov (United States)

    Sakai, Tsuyoshi; Umeki, Nobuhisa; Ikebe, Reiko; Ikebe, Mitsuo

    2011-04-26

    Myosin VIIA, thought to be involved in human auditory function, is a gene responsible for human Usher syndrome type 1B, which causes hearing and visual loss. Recent studies have suggested that it can move processively if it forms a dimer. Nevertheless, it exists as a monomer in vitro, unlike the well-known two-headed processive myosin Va. Here we studied the molecular mechanism, which is currently unknown, of activating myosin VIIA as a cargo-transporting motor. Human myosin VIIA was present throughout cytosol, but it moved to the tip of filopodia upon the formation of dimer induced by dimer-inducing reagent. The forced dimer of myosin VIIA translocated its cargo molecule, MyRip, to the tip of filopodia, whereas myosin VIIA without the forced dimer-forming module does not translocate to the filopodial tips. These results suggest that dimer formation of myosin VIIA is important for its cargo-transporting activity. On the other hand, myosin VIIA without the forced dimerization module became translocated to the filopodial tips in the presence of cargo complex, i.e., MyRip/Rab27a, and transported its cargo complex to the tip. Coexpression of MyRip promoted the association of myosin VIIA to vesicles and the dimer formation. These results suggest that association of myosin VIIA monomers with membrane via the MyRip/Rab27a complex facilitates the cargo-transporting activity of myosin VIIA, which is achieved by cluster formation on the membrane, where it possibly forms a dimer. Present findings support that MyRip, a cargo molecule, functions as an activator of myosin VIIA transporter function.

  7. Differences of Respiratory Function According to Level of the Gross Motor Function Classification System in Children with Cerebral Palsy

    OpenAIRE

    Kwon, Yong Hyun; Lee, Hye Young

    2014-01-01

    [Purpose] The current study was designed to investigate the difference in lung capacity and muscle strengthening related to respiration depending on the level of the Gross Motor Function Classification System (GMFCS) in children with cerebral palsy (CP) through tests of respiratory function and respiratory pressure. [Subjects and Methods] A total of 49 children with CP who were classified as below level III of the GMFCS were recruited for this study. They were divided into three groups (i.e.,...

  8. DSP-Based Sensorless Speed Control of a Permanent Magnet Synchronous Motor using Sliding Mode Current Observer

    Directory of Open Access Journals (Sweden)

    Rachid Askour

    2014-05-01

    Full Text Available In this paper, experimental results of 3-phase permanent magnet synchronous motor (PMSM sensorless speed control are presented. To estimate the rotor position, a sliding mode current observer (SMCO was implemented. This observer estimates the back emfs of the motor in the stationary reference frame using only the measured voltages and currents of the motor. These emfs were utilized to obtain the rotor position. The speed of the motor was calculated by differentiating the rotor position angle. The stability of the proposed SMCO was verified using Lyapunov method to determine the observer gain. The saturation function was adopted in order to reduce the chattering phenomenon caused by the SMCO. A vector control method was employed to achieve the sensorless drive system. The control application was developed in C/C++ language and implemented using the Texas Instruments TMS320LF2812 digital signal processor (DSP. This new processor enables intelligent control for motors. We used to test the drive the MCK2812 which is a professional development kit available from Technosoft Company. The theoretical finding is validated with experimental results that show the effectiveness of the real-time implementation.

  9. SMN is required for sensory-motor circuit function in Drosophila.

    Science.gov (United States)

    Imlach, Wendy L; Beck, Erin S; Choi, Ben Jiwon; Lotti, Francesco; Pellizzoni, Livio; McCabe, Brian D

    2012-10-12

    Spinal muscular atrophy (SMA) is a lethal human disease characterized by motor neuron dysfunction and muscle deterioration due to depletion of the ubiquitous survival motor neuron (SMN) protein. Drosophila SMN mutants have reduced muscle size and defective locomotion, motor rhythm, and motor neuron neurotransmission. Unexpectedly, restoration of SMN in either muscles or motor neurons did not alter these phenotypes. Instead, SMN must be expressed in proprioceptive neurons and interneurons in the motor circuit to nonautonomously correct defects in motor neurons and muscles. SMN depletion disrupts the motor system subsequent to circuit development and can be mimicked by the inhibition of motor network function. Furthermore, increasing motor circuit excitability by genetic or pharmacological inhibition of K(+) channels can correct SMN-dependent phenotypes. These results establish sensory-motor circuit dysfunction as the origin of motor system deficits in this SMA model and suggest that enhancement of motor neural network activity could ameliorate the disease.

  10. The quick motor function test: a new tool to rate clinical severity and motor function in Pompe patients

    NARCIS (Netherlands)

    C.I. van Capelle (Carine); N.A.M.E. van der Beek (Nadine); J.M. de Vries (Juna); P.A. van Doorn (Pieter); H.J. Duivenvoorden (Hugo); R.T. Leshner (Robert T.); M.L.C. Hagemans (Marloes); A.T. van der Ploeg (Ans)

    2012-01-01

    textabstractPompe disease is a lysosomal storage disorder characterized by progressive muscle weakness. With the emergence of new treatment options, psychometrically robust outcome measures are needed to monitor patients' clinical status. We constructed a motor function test that is easy and quick

  11. The double-temperature ratchet model and current reversal of coupled Brownian motors

    CERN Document Server

    Li, Chen-pu; Zheng, Zhi-gang

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    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

  13. Aging-associated changes in motor axon voltage-gated Na(+) channel function in mice

    DEFF Research Database (Denmark)

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

    2016-01-01

    Accumulating myelin abnormalities and conduction slowing occur in peripheral nerves during aging. In mice deficient of myelin protein P0, severe peripheral nervous system myelin damage is associated with ectopic expression of Nav1.8 voltage-gated Na(+) channels on motor axons aggravating...... 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....... With aging, deviations during threshold electrotonus were attenuated and the resting current-threshold slope and early refractoriness were increased. Modeling indicated that, in addition to changes in passive membrane properties, motor fibers in aged WT mice were depolarized. An increased Nav1.8 isoform...

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Developmental changes in motor cortex activity as infants develop functional motor skills.

    Science.gov (United States)

    Nishiyori, Ryota; Bisconti, Silvia; Meehan, Sean K; Ulrich, Beverly D

    2016-09-01

    Despite extensive research examining overt behavioral changes of motor skills in infants, the neural basis underlying the emergence of functional motor control has yet to be determined. We used functional near-infrared spectroscopy (fNIRS) to record hemodynamic activity of the primary motor cortex (M1) from 22 infants (11 six month-olds, 11 twelve month-olds) as they reached for an object, and stepped while supported over a treadmill. Based on the developmental systems framework, we hypothesized that as infants increased goal-directed experience, neural activity shifts from a diffused to focal pattern. Results showed that for reaching, younger infants showed diffuse areas of M1 activity that became focused by 12 months. For elicited stepping, younger infants produced much less M1 activity which shifted to diffuse activity by 12 months. Thus, the data suggest that as infants gain goal-directed experience, M1 activity emerges, initially showing a diffuse area of activity, becoming refined as the behavior stabilizes. Our data begin to document the cortical activity underlying early functional skill acquisition.

  17. Robotic Characterization of Ipsilesional Motor Function in Subacute Stroke.

    Science.gov (United States)

    Semrau, Jennifer A; Herter, Troy M; Kenzie, Jeffrey M; Findlater, Sonja E; Scott, Stephen H; Dukelow, Sean P

    2017-06-01

    Poststroke impairments of the ipsilesional arm are often discussed, but rarely receive focused rehabilitation. Ipsilesional deficits may affect daily function and although many studies have investigated them in chronic stroke, few characterizations have been made in the subacute phase. Furthermore, most studies have quantified ipsilesional deficits using clinical measures that can fail to detect subtle, but important deficits in motor function. We aimed to quantify reaching deficits of the contra- and ipsilesional limbs in the subacute phase poststroke. A total of 227 subjects with first-time, unilateral stroke completed a unilateral assessment of motor function (visually guided reaching) using a KINARM robot. Subjects completed the task with both the ipsi- and contralesional arms. Subjects were assessed on a variety of traditional clinical measures (Functional Independence Measure, Chedoke-McMaster Stroke Assessment, Purdue Pegboard, Behavioral Inattention Test) to compare with robotic measures of motor function. Ipsilesional deficits were common and occurred in 37% (n = 84) of subjects. Impairments of the ipsilesional and contralesional arm were weakly to moderately correlated on robotic measures. Magnitude of impairment of the contralesional arm was similar for subjects with and without ipsilesional deficits. Furthermore, we found that a higher percentage of subjects with right-hemisphere stroke had ipsilesional deficits and more subjects with left-hemisphere subcortical strokes did not have ipsilesional deficits. Magnitude of contralesional impairment and lesion location may be poor predictors of individuals with ipsilesional impairments after stroke. Careful characterization of ipsilesional deficits could identify individuals who may benefit from rehabilitation of the less affected arm.

  18. Mirror therapy for improving motor function after stroke.

    Science.gov (United States)

    Thieme, Holm; Mehrholz, Jan; Pohl, Marcus; Behrens, Johann; Dohle, Christian

    2012-03-14

    Mirror therapy is used to improve motor function after stroke. During mirror therapy, a mirror is placed in the patient's midsagittal plane, thus reflecting movements of the non-paretic side as if it were the affected side. To summarise the effectiveness of mirror therapy for improving motor function, activities of daily living, pain and visuospatial neglect in patients after stroke. We searched the Cochrane Stroke Group's Trials Register (June 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 2), MEDLINE (1950 to June 2011), EMBASE (1980 to June 2011), CINAHL (1982 to June 2011), AMED (1985 to June 2011), PsycINFO (1806 to June 2011) and PEDro (June 2011). We also handsearched relevant conference proceedings, trials and research registers, checked reference lists and contacted trialists, researchers and experts in our field of study. We included randomised controlled trials (RCTs) and randomised cross-over trials comparing mirror therapy with any control intervention for patients after stroke. Two review authors independently selected trials based on the inclusion criteria, documented the methodological quality of studies and extracted data. We analysed the results as standardised mean differences (SMDs) for continuous variables. We included 14 studies with a total of 567 participants that compared mirror therapy with other interventions. When compared with all other interventions, mirror therapy may have a significant effect on motor function (post-intervention data: SMD 0.61; 95% confidence interval (CI) 0.22 to 1.0; P = 0.002; change scores: SMD 1.04; 95% CI 0.57 to 1.51; P < 0.0001). However, effects on motor function are influenced by the type of control intervention. Additionally, mirror therapy may improve activities of daily living (SMD 0.33; 95% CI 0.05 to 0.60; P = 0.02). We found a significant positive effect on pain (SMD -1.10; 95% CI -2.10 to -0.09; P = 0.03) which is influenced by patient population

  19. SIMULATION AND IMPLEMENTATION OF CURRENT CONTROL OF BRUSHLESS DC MOTOR BASED ON A COMMON DC SIGNAL

    Directory of Open Access Journals (Sweden)

    J.Karthikeyan

    2010-06-01

    Full Text Available The objective of this project is to build a simple current controlled modulation technique for brushless dc motors. In electric traction and most other applications, a wide range of speed and torque control of the electric motor is required. The dc machine fulfills these requirements, but the dc machine requires constant maintenance. But the brushless permanent magnet motors do not have brushes and so they require less maintenance only. Brushless dc motors are widely used in applications which require wide range of speed and torque control because of its low inertia, fast response, high reliability and maintenance free. This current controlled technique is based on the generation of quasi- square wave currents using only one controller for the three phases. The current control strategy uses a triangular carrier for the power transistors which is simpler and more accuratethan any other options. The advantages of this technique are: a The stator currents are completely characterized by their maximum amplitude , b The three phases are controlled with the same dc component , and then the phase currents are kept at exactly the same magnitude I max, c The dc link current measurement is not required .d phase currents are kept balanced and phase over currents are eliminated.

  20. Impact Analysis of Dwell Angles on Current Shape and Torque in Switched Reluctance Motors

    Directory of Open Access Journals (Sweden)

    Syeda Fatima Ghousia

    2012-03-01

    Full Text Available The reduction of torque ripple is the main target in research for designing a variable drive system with switched reluctance motors (SRM for higher torque density and better efficiency. This ripple is due to the transition of excitation current between the adjacent phases. Precise control of turn-on and turn off angle is required to smooth the torque. In this paper, the effects of selecting the turn-on and turn-off angles are simulated in detail. It is observed that with the extended turn-on and turn off angles, the precise selection of turn-on and turn off angle can alter the shape of the excitation current in the stator coil and its point of overlapping with the adjacent coil. Therefore the transition between different phases can be smoothed out. The impact of this alteration on the excitation current and torque ripple as a function of different parameters of dwell angle is studied in detail in this paper. It is found that a sinusoidal current shape can also be obtained with the proper selection of these parameters.

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

    Directory of Open Access Journals (Sweden)

    Maria Zaskalicka

    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.

  2. Human Motor Cortex Functional Changes in Acute Stroke: Gender Effects

    Directory of Open Access Journals (Sweden)

    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.

  3. Facilitating skilled right hand motor function in older subjects by anodal polarization over the left primary motor cortex.

    Science.gov (United States)

    Hummel, Friedhelm C; Heise, Kirstin; Celnik, Pablo; Floel, Agnes; Gerloff, Christian; Cohen, Leonardo G

    2010-12-01

    Healthy ageing is accompanied by limitations in performance of activities of daily living and personal independence. Recent reports demonstrated improvements in motor function induced by noninvasive anodal direct current stimulation (tDCS) of the primary motor cortex (M1) in young healthy adults. Here we tested the hypothesis that a single session of anodal tDCS over left M1 could facilitate performance of right upper extremity tasks required for activities of daily living (Jebsen-Taylor hand function test, JTT) in older subjects relative to Sham in a double-blind cross-over study design. We found (a) significant improvement in JTT function with tDCS relative to Sham that outlasted the stimulation period by at least 30 min, (b) that the older the subjects the more prominent this improvement appeared and (c) that consistent with previous results in younger subjects, these effects were not accompanied by any overt undesired side effect. We conclude that anodal tDCS applied over M1 can facilitate performance of skilled hand functions required for activities of daily living in older subjects.

  4. 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.

  5. Time-frequency vibration analysis for the detection of motor damages caused by bearing currents

    Science.gov (United States)

    Prudhom, Aurelien; Antonino-Daviu, Jose; Razik, Hubert; Climente-Alarcon, Vicente

    2017-02-01

    Motor failure due to bearing currents is an issue that has drawn an increasing industrial interest over recent years. Bearing currents usually appear in motors operated by variable frequency drives (VFD); these drives may lead to common voltage modes which cause currents induced in the motor shaft that are discharged through the bearings. The presence of these currents may lead to the motor bearing failure only few months after system startup. Vibration monitoring is one of the most common ways for detecting bearing damages caused by circulating currents; the evaluation of the amplitudes of well-known characteristic components in the vibration Fourier spectrum that are associated with race, ball or cage defects enables to evaluate the bearing condition and, hence, to identify an eventual damage due to bearing currents. However, the inherent constraints of the Fourier transform may complicate the detection of the progressive bearing degradation; for instance, in some cases, other frequency components may mask or be confused with bearing defect-related while, in other cases, the analysis may not be suitable due to the eventual non-stationary nature of the captured vibration signals. Moreover, the fact that this analysis implies to lose the time-dimension limits the amount of information obtained from this technique. This work proposes the use of time-frequency (T-F) transforms to analyse vibration data in motors affected by bearing currents. The experimental results obtained in real machines show that the vibration analysis via T-F tools may provide significant advantages for the detection of bearing current damages; among other, these techniques enable to visualise the progressive degradation of the bearing while providing an effective discrimination versus other components that are not related with the fault. Moreover, their application is valid regardless of the operation regime of the machine. Both factors confirm the robustness and reliability of these tools

  6. CURRENT VECTOR CONTROL OF PERMANENT-MAGNET SYNCHRONOUS MOTOR OF HYBRID VEHICLE ENGINE

    Directory of Open Access Journals (Sweden)

    S. Serikov

    2009-01-01

    Full Text Available Characteristics of traction permanent-magnet synchronous motor under current vector optimum control in the possible traction-speed mode area which are relevant for hybrid vehicle engine have been investigated. As a criterion of optimality a maximum of electromagnetic moment per unit of current have been taken.

  7. 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....

  8. 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....

  9. fMRI as a molecular imaging procedure for the functional reorganization of motor systems in chronic stroke

    Science.gov (United States)

    LAZARIDOU, ASIMINA; ASTRAKAS, LOUKAS; MINTZOPOULOS, DIONYSSIOS; KHANCHICEH, AZADEH; SINGHAL, ANEESH; MOSKOWITZ, MICHAEL; ROSEN, BRUCE; TZIKA, ARIA

    2013-01-01

    Previous brain imaging studies suggest that stroke alters functional connectivity in motor execution networks. Moreover, current understanding of brain plasticity has led to new approaches in stroke rehabilitation. Recent studies showed a significant role of effective coupling of neuronal activity in the SMA (supplementary motor area) and M1 (primary motor cortex) network for motor outcome in patients after stroke. After a subcortical stroke, functional magnetic resonance imaging (fMRI) during movement reveals cortical reorganization that is associated with the recovery of function. The aim of the present study was to explore connectivity alterations within the motor-related areas combining motor fMRI with a novel MR-compatible hand-induced robotic device (MR_CHIROD) training. Patients completed training at home and underwent serial MR evaluation at baseline and after 8 weeks of training. Training at home consisted of squeezing a gel exercise ball with the paretic hand at ~75% of maximum strength for 1 h/day, 3 days/week. The fMRI analysis revealed alterations in M1, SMA, PMC (premotor cortex) and Cer (cerebellum) in both stroke patients and healthy controls after the training. Findings of the present study suggest that enhancement of SMA activity could benefit M1 dysfunction in stroke survivors. These results also indicate that connectivity alterations between motor areas might assist the counterbalance of a functionally abnormal M1 in chronic stroke survivors and possibly other patients with motor dysfunction. PMID:23900349

  10. 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

    harmonic mitigation methods have been developed over the years, the total cost and complexity has become the main obstacle in employing prior-art methods for motor drive systems. This paper presents a novel current modulation method based on the electronic inductor concept for three-phase ac-dc systems......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...... to reduce input current harmonics. The obtained results at simulation and experimental levels confirm the effectiveness of the proposed approach....

  11. Bearingless motor's radial suspension force control based on flux equivalent with virtual winding current analysis method

    Institute of Scientific and Technical Information of China (English)

    ZHU HuangQiu; CHENG OiuLiang

    2009-01-01

    A bearingless motor has two sets of intercoupling stator windings, namely torque windings and sus-pension force windings. The decoupling control of the two sets is difficult and a key technology to stable operation for a bearingless motor. In this paper, a simple, reliable and accurate analysis method is put forward using the concept of flux equivalent with virtual winding currents. By this method, the suspension operation condition PB=PM±1 for bearingless motors is testified, and under the rotation condition of the motor, it is also proved that currents in suspension force windings must have the same phase sequence and frequency as torque windings to generate a stable single direction radial force in the rotor's whole circumference. On this basis, the control strategy of realizing the suspension opera-tion of the bearingless motor is presented, and a prototype of the bearingless surface-mounted per-manent magnet synchronous motor is tested. The research results have indicated that the experimen-tal results correspond with theoretical analysis adopting this method, a stable and reliable radial sus-pension force can be generated, and the validity and feasibility of this control strategy are confirmed.

  12. Influence of mental practice and movement observation on motor memory, cognitive function and motor performance in the elderly

    Directory of Open Access Journals (Sweden)

    Caroline D. C. Altermann

    2014-04-01

    Full Text Available BACKGROUND: With aging, it is important to maintain cognitive and motor functions to ensure autonomy and quality of life. During the acquisition of motor skills, it is necessary for the elderly to understand the purpose of the proposed activities. Physical and mental practice, as well as demonstrations, are strategies used to learn movements. OBJECTIVES: To investigate the influence of mental practice and the observation of movement on motor memory and to understand the relationship between cognitive function and motor performance in the execution of a sequence of digital movements in the elderly. METHOD: This was a cross-sectional study conducted with 45 young and 45 aged subjects. The instruments used were Mini-Mental State Examination (MMSE, Manual Preference Inventory and a Digital Motor Task (composed of a training of a sequence of movements, an interval and a test phase. The subjects were divided into three subgroups: control, mental practice and observation of movement. RESULTS: The elderly depend more strongly on mental practice for the acquisition of a motor memory. In comparing the performances of people in different age groups, we found that in the elderly, there was a negative correlation between the MMSE score and the execution time as well as the number of errors in the motor task. CONCLUSIONS: For the elderly, mental practice can advantage motor performance. Also, there is a significant relationship between cognitive function, learning and the execution of new motor skills.

  13. Smart Technique for Induction Motors Diagnosis by Monitoring the Power Factor Using Only the Measured Current

    Science.gov (United States)

    Shnibha, R. A.; Albarabar, A. S.

    2012-05-01

    This paper is concerned with accurate, early and reliable induction motor IM fault detection and diagnosis using an enhanced power parameter measurement technique. IM protection devices typically monitor the motor current and/or voltage to provide the motor protection from e.g. current overload, over/under voltage, etc. One of the interesting parameters to monitor is the operating power factor (PF) of the IM which provides better under-load protection compared to the motor current based approaches. The PF of the motor is determined by the level of the current and voltage that are drawn, and offers non-intrusive monitoring. Traditionally, PF estimation would require both voltage and the current measurements to apply the displacement method. This paper will use a method of determining the operating PF of the IM using only the measured current and the manufacturer data that are typically available from the nameplate and/or datasheet for IM monitoring. The novelty of this work lies in detecting very low phase imbalance related faults and misalignment. Much of the previous work has dealt with detecting phase imbalance faults at higher degrees of severity, i.e. voltage drops of 10% or more. The technique was tested by empirical measurements on test rig comprised a 1.1 kW variable speed three phase induction motor with varying output load (No load, 25%, 50%, 75% and 100% load). One common faults was introduced; imbalance in one phase as the electrical fault The experimental results demonstrate that the PF can be successfully applied for IM fault diagnosis and the present study shows that severity fault detection using PF is promising. The proposed method offers a potentially reliable, non-intrusive, and inexpensive CM tool which can be implemented with real-time monitoring systems

  14. Compact ASD Topologies for Single-Phase Integrated Motor Drives with Sinusoidal Input Current

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede; Thoegersen, Paul

    2005-01-01

    A standard configuration of an Adjustable Speed Drive (ASD) consists of two separate units: an AC motor, which runs with fixed speed when it is supplied from a constant frequency grid voltage and a frequency converter, which is used to provide the motor with variable voltage-variable frequency...... needed to adjust the speed of the motor. The integrated motor drive concept is a result of merging the two units in order to achieve the following benefits [1-3]: reducing the design and the commissioning time in complex industrial equipments, no need for a cabinet to host the frequency converter......, no needfor shielded cables to reduce EM1 (Electro Magnetic Inteiference), no needfor cables for the speed transducers or for other sensorsfor industrial process control (e.g. pressure). This solution is currently available up to 7.5 kW being not used in the medium and high power range due to a low...

  15. Finite Element Analysis of a BLDC Motor Considering the Eddy Current in Rotor Steel Shell

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung Chan; Yoon, Tae Ho; Kwon Byung Il [Hanyang University (Korea, Republic of); Yoon, Hee Soo; Won, Sung Hong [Samsung Electro-Mechanics R and D Center (Korea, Republic of)

    1999-03-01

    This paper describes the effect of eddy currents in the rotor steel shell of exterior-rotor permanent magnet BLDC motor of which rotor is revolving at a high speed. A two-dimensional time-stepping finite element method is used for analyzing electromagnetic field and computing performances of the motor. As a result, the effect of the eddy currents in the rotor steel shell is shown by comparing the analysis results from both the proposed method and the conventional one. (author). 7 refs., 11 figs., 1 tab.

  16. 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

  17. Sensori-motor function in older persons with diabetes.

    Science.gov (United States)

    Lord, S R; Caplan, G A; Colagiuri, R; Colagiuri, S; Ward, J A

    1993-01-01

    Twenty-five persons with diabetes (aged 55-83 years) who were living independently in the community, and 40 age- and sex-matched non-diabetic controls were assessed for tactile sensitivity, vibration sense, proprioception, quadriceps strength and body sway. In both men and women, those with diabetes performed significantly worse in tests of body sway on firm and compliant surfaces compared with the control subjects after controlling for weight and body mass index. The female diabetic subjects also performed significantly worse in tests of peripheral sensation and strength compared with controls. Age-related declines in sensori-motor function were greater in the diabetic group (r = 0.55-0.75) than in the controls (r vibration sense were significantly correlated with sway on a compliant (foam rubber) surface with the eyes open (partial r = 0.52, p problems with stability and related sensori-motor factors which may place them at increased risk of falls.

  18. Differential functioning of Bender Visual-Motor Gestalt Test items.

    Science.gov (United States)

    Sisto, Fermino Fernandes; Dos Santos, Acácia Aparecida Angeli; Noronha, Ana Paula Porto

    2010-02-01

    Differential Item Functioning (DIF) refers to items that do not function the same way for comparable members of different groups. The present study focuses on analyzing and classifying sex-related differential item functioning in the Bender Visual-Motor Gestalt Test. Subjects were 1,052 children attending public schools (513 boys, 539 girls, ages 6-10 years). The protocols were scored using the Bender Graduated Scoring System, which evaluates only the distortion criterion using the Rasch logistic response model. The scoring system fit the Rasch model, although two items were found to be biased by sex. When analyzing differential functioning of items for boys and girls separately, the number of differentially functioning items was equal.

  19. The functional role of motor activation in language processing: Motor cortical oscillations support lexical-semantic retrieval

    NARCIS (Netherlands)

    M. van Elk (M.); H.T. van Schie (H.); R.A. Zwaan (Rolf); H. Bekkering (H.)

    2010-01-01

    textabstractThere is increasing experimental evidence that processing action-related language results in the automatic activation of associated regions of the motor and premotor cortex. However, the functional significance of motor activation in language processing is still under debate. In the

  20. The functional role of motor activation in language processing: Motor cortical oscillations support lexical-semantic retrieval

    NARCIS (Netherlands)

    Elk, M. van; Schie, H.T. van; Zwaan, R.A.; Bekkering, H.

    2010-01-01

    There is increasing experimental evidence that processing action-related language results in the automatic activation of associated regions of the motor and premotor cortex. However, the functional significance of motor activation in language processing is still under debate. In the present EEG

  1. Accommodation to hyperpolarizing currents: differences between motor and sensory nerves in mice.

    Science.gov (United States)

    Nodera, Hiroyuki; Rutkove, Seward B

    2012-06-19

    Peripheral motor nerves have revealed variability in excitability by hyperpolarizing current at specific target response levels, likely reflecting differences in the hyperpolarization-activated current (Ih). Whether such variability in Ih exists in sensory axons is yet to be established. We performed nerve excitability testing in mouse tail motor and sensory nerves at 3 target response levels (20, 40, and 60% of the maximum amplitudes). Target-level dependent variability was present by long hyperpolarizing currents in motor and sensory nerves in which the recording at the low target level showed smaller threshold changes than at the high target level. Other excitability measures, however, showed no variability. Furthermore, the accommodation by long, strong hyperpolarization revealed smaller S3 accommodation (threshold change between the maximum and at the end of the 200 ms conditioning pulse) at the low target response level in sensory axons, but not in motor axons. Variation in the kinetics of the subtypes of the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in motor and sensory axons is the most likely explanation for these findings. The present study has proposed that nerve excitability testing may provide a non-invasive means for the assessment of the different types of Ih in neurological disorders where HCN subtypes play unique pathophysiological roles.

  2. Gross Motor Function Classification System used in adults with cerebral palsy: agreement of self-reported versus professional rating.

    Science.gov (United States)

    Jahnsen, Reidun; Aamodt, Geir; Rosenbaum, Peter

    2006-09-01

    The present study investigated the reliability of self-reported rating of Gross Motor Function Classification System (GMFCS) levels compared with professional rating, and changes in gross motor function over time, in adults with cerebral palsy. Twenty-nine females and 33 males aged between 18 years 5 months and 62 years 11 months (mean age 34y 7mo [SD 10y 6mo]) participated in the study. Participants rated their current gross motor function using the GMFCS and reported their judgement of their gross motor function at age 10 to 12 years. The project leader, a physical therapist, also classified participants' current GMFCS levels and conducted a chart review on all accessible medical records of participants' gross motor function when they were 10 to 12 years old, rating the GMFCS level accordingly. Intraclass correlation coefficients (ICC) between self-reported and professional ratings showed excellent agreement (ICC=0.93-0.95, 95% confidence interval [CI] 0.89-0.97). More than half the participants experienced a stable gross motor function from the age of 10 to 12 years to the present. Those at GMFCS Levels II and III at the age of 10 to 12 years (according to the professional rating) had significant change for the worse in gross motor function over time, with odds ratios of 9.30 (95% CI 1.2-73.0, p=0.03) and 7.00 (95% CI 1.1-43.0, p=0.04) respectively. Interview data on circumstances regarding changes in gross motor function since childhood are also reported. Changes in GMFCS level were mostly associated with physical or social environmental factors.

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

    Science.gov (United States)

    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.

  4. COMPARISON PERFORMANCE OF INDUCTION MOTOR USING SVPWM AND HYSTERESIS CURRENT CONTROLLER

    Directory of Open Access Journals (Sweden)

    FIZATUL AINI PATAKOR

    2011-08-01

    Full Text Available This paper presents the comparative performances of three phase induction motors using space vector pulse width modulation (SVPWM and hysteresis current controller. An indirect field orientation is applied to ensure decoupling control between torque and flux of the induction motor. The hysteresis current controller is built in with PI speed controller and three hysteresis current bands while the SVPWM system is embedded with the two control loops, the inner current control loop and the outer speed control loop using PI controller. Both systems were run and tested using MATLAB/SIMULINK software. The simulation results demonstrate that the SVPWM can improve the quality of the stator current and reduce the torque ripple while maintaining the other performance characteristics of the system.

  5. EFFECT OF SENSORY INTEGRATION THERAPY ON GROSS MOTOR FUNCTION IN CHILDREN WITH CEREBRAL PALSY

    Directory of Open Access Journals (Sweden)

    A.R. Shamsoddini

    2009-04-01

    Full Text Available ObjectiveThe primary problem in children with cerebral palsy (CP, frequently referred for occupational therapy, is gross motor dysfunction. The current study was designed to investigate the effects of sensory integration therapy (SIT on gross motor skills in CP patients.Materials & MethodsTwenty-four children with diplegic spastic CP were randomly divided into two groups: First group (n=14,6 girls, 8 boys, age range 2 to 6 years, mean age 3.9 years; the second or control group (n=10, 5 girls, 5 boys, age range 2 to 6 years, mean age 3.4 years. SIT training was given to the first group and only the home program was given for the second group. All children were evaluated with gross motor function measurement (GMFM 88 for rolling, sitting, crawling, standing and walking position before and after intervention. Treatment duration for both groups was 1 hour, 5 days per week for a period of 12 weeks.ResultsGross motor function in children of the case group improved significantly better that in the control group, after intervention in sitting (P=0.02, crawling (P=0.001 and standing (P=0.03 positions; however no significant difference was seen in rolling (P=0.65 and walking (P=0.69 ability assessment.ConclusionThis study showed the beneficial effects of the SIT training program for children with CP; the SIT intervention had a significantly positive effect on gross motor function in the children with diplegic spastic CP. Moreover the results of the present study showed that sensory integration and vestibular stimulation were effective in children with cerebral palsy.Keywords:Cerebral palsy, Children, Gross motor, Occupational therapy, Sensory integration

  6. Geared induction motor fault diagnosis by current, noise and vibration considering measurement environment

    Directory of Open Access Journals (Sweden)

    Ki-Seok Kim

    2017-01-01

    Full Text Available Lots of motors have been being used in industry. Therefore many studies have been carried out about the failure diagnosis of motors. In this paper, a diagnosis of gear fault connected to a motor shaft is studied. The fault diagnosis is executed through the comparison of normal gear and abnormal gear. In the abnormal gearbox, a tooth of the intermediate gear is damaged. The measured FFT data are compared with the normal data and analyzed for q-axis current, noise and vibration. Fault gear was found by comparing the FFT with normal FFT. From these, the difference between the normal and abnormal states can be seen by the frequency characteristic analysis for the current as well as noise and vibration.

  7. Detection of outer raceway bearing defects in small induction motors using stator current analysis

    Indian Academy of Sciences (India)

    İzzet Y Önel; K Burak Dalci; İbrahim Senol

    2005-12-01

    We investigate the application of induction motor stator current spectral analysis (MCSA) for detection of rolling element bearing damage from the outer raceway. In this work, MCSA and vibration analysis are applied to induction motor to detect outer raceway defects in faulty bearings. Data acquisition, recording,and fast fourier transform (FFT) algorithms are done by using the LabVIEW programming language. Experimental results verify the relationship between vibration analysis and MCSA, and identify the presence of outer raceway bearing defects in induction machines. This work also indicates that detecting fault frequencies by motor currents is more difficult than detecting them by vibration analysis. The use of intensive resolution FFT is recommended in MCSA for detecting faults easily. Reinstalling a faulty bearing can alter the characteristic frequencies and it is difficult to compare results from different bearings or even from the same bearing in different installations.

  8. Bearing fault detection using motor current signal analysis based on wavelet packet decomposition and Hilbert envelope

    Directory of Open Access Journals (Sweden)

    Imaouchen Yacine

    2015-01-01

    Full Text Available To detect rolling element bearing defects, many researches have been focused on Motor Current Signal Analysis (MCSA using spectral analysis and wavelet transform. This paper presents a new approach for rolling element bearings diagnosis without slip estimation, based on the wavelet packet decomposition (WPD and the Hilbert transform. Specifically, the Hilbert transform first extracts the envelope of the motor current signal, which contains bearings fault-related frequency information. Subsequently, the envelope signal is adaptively decomposed into a number of frequency bands by the WPD algorithm. Two criteria based on the energy and correlation analyses have been investigated to automate the frequency band selection. Experimental studies have confirmed that the proposed approach is effective in diagnosing rolling element bearing faults for improved induction motor condition monitoring and damage assessment.

  9. 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.

  10. Electrical motor current signal analysis using a modified bispectrum for fault diagnosis of downstream mechanical equipment

    Science.gov (United States)

    Gu, F.; Shao, Y.; Hu, N.; Naid, A.; Ball, A. D.

    2011-01-01

    This paper presents the use of the induction motor current to identify and quantify common faults within a two-stage reciprocating compressor based on bispectrum analysis. The theoretical basis is developed to understand the nonlinear characteristics of current signals when the motor undertakes a varying load under different faulty conditions. Although conventional bispectrum representation of current signal allows the inclusion of phase information and the elimination of Gaussian noise, it produces unstable results due to random phase variation of the sideband components in the current signal. A modified bispectrum based on the amplitude modulation feature of the current signal is then adopted to combine both lower sidebands and higher sidebands simultaneously and hence characterise the current signal more accurately. Based on this new bispectrum analysis a more effective diagnostic feature, namely normalised bispectral peak, is developed for fault classification. In association with the kurtosis value of the raw current signal, the bispectrum feature gives rise to reliable fault classification results. In particular, the low feature values can differentiate the belt looseness from the other fault cases and different degrees of discharge valve leakage and inter-cooler leakage can be separated easily using two linear classifiers. This work provides a novel approach to the analysis of stator current for the diagnosis of motor drive faults from downstream driving equipment.

  11. Diagnostics of induction motor based on spectral analysis of stator current signal with application of fuzzy classifier

    OpenAIRE

    W. Głowacz; A. Głowacz

    2010-01-01

    New implementation of diagnostics of imminent failure conditions of induction motor was presented. Software to recognize the current ofinduction motor was implemented. System of current recognition is based on a study of the frequency spectrum of stator current signal.Fuzzy classifier was applied. The studies were carried out for four imminent failure conditions of induction motor. The results confirm thatthe system can be useful for detecting damage and protect the engines.

  12. Changes in motor function in the unaffected hand of stroke patients should not be ignored

    Institute of Scientific and Technical Information of China (English)

    Lingli Zhang; Peihong Li; Zhibang Mao; Xiang Qi; Jun Zou; Zhusheng Yu

    2014-01-01

    Motor function changes in the unaffected hand of stroke patients with hemiplegia. These chang-es are often ignored by clinicians owing to the extent of motor disability of the affected hand. Finger tapping frequency and Lind-mark hand function score showed that the motor function of unaffected hands in stroke patients was poorer than that of a healthy control hand. After 2 weeks of rehabilitation treatment, motor function of the unaffected hand of stroke patients was obviously improved. Therefore, attention should also be paid to motor function in the unaffect-ed hand of stroke patients with hemiplegia during rehabilitation.

  13. Aging-associated changes in motor axon voltage-gated Na(+) channel function in mice.

    Science.gov (United States)

    Moldovan, Mihai; Rosberg, Mette Romer; Alvarez, Susana; Klein, Dennis; Martini, Rudolf; Krarup, Christian

    2016-03-01

    Accumulating myelin abnormalities and conduction slowing occur in peripheral nerves during aging. In mice deficient of myelin protein P0, severe peripheral nervous system myelin damage is associated with ectopic expression of Nav1.8 voltage-gated Na(+) channels on motor axons aggravating 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. With aging, deviations during threshold electrotonus were attenuated and the resting current-threshold slope and early refractoriness were increased. Modeling indicated that, in addition to changes in passive membrane properties, motor fibers in aged WT mice were depolarized. An increased Nav1.8 isoform 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 during aging.

  14. Functional magnetic resonance imaging of the primary motor cortex in humans: response to increased functional demands.

    Science.gov (United States)

    Khushu, S; Kumaran, S S; Tripathi, R P; Gupta, A; Jain, P C; Jain, V

    2001-06-01

    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 in six different sessions of a volunteer over a period of one month. Increased tapping rate resulted in increase in the blood oxygenation level dependent (BOLD) signal intensity as well as the volume/area of activation (pixels) in the contralateral primary motor area up to tapping rate of 120 taps/min (2 Hz), beyond which it saturates. Activation in supplementary motor area was also observed. The obtained results are correlated to increased functional demands.

  15. Functional magnetic resonance imaging of the primary motor cortex in humans: response to increased functional demands

    Indian Academy of Sciences (India)

    S Khushu; S S Kumaran; R P Tripathi; A Gupta; P C Jain; V Jain

    2001-06-01

    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 in six different sessions of a volunteer over a period of one month. Increased tapping rate resulted in increase in the blood oxygenation level dependent (BOLD) signal intensity as well as the volume/area of activation (pixels) in the contralateral primary motor area up to tapping rate of 120 taps/min (2 Hz), beyond which it saturates. Activation in supplementary motor area was also observed. The obtained results are correlated to increased functional demands.

  16. 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...

  17. Motor and somatosensory conversion disorder: a functional unawareness syndrome?

    Science.gov (United States)

    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.

  18. Structure and Function of the Bi-Directional Bacterial Flagellar Motor

    Directory of Open Access Journals (Sweden)

    Yusuke V. Morimoto

    2014-02-01

    Full Text Available The bacterial flagellum is a locomotive organelle that propels the bacterial cell body in liquid environments. The flagellum is a supramolecular complex composed of about 30 different proteins and consists of at least three parts: a rotary motor, a universal joint, and a helical filament. The flagellar motor of Escherichia coli and Salmonella enterica is powered by an inward-directed electrochemical potential difference of protons across the cytoplasmic membrane. The flagellar motor consists of a rotor made of FliF, FliG, FliM and FliN and a dozen stators consisting of MotA and MotB. FliG, FliM and FliN also act as a molecular switch, enabling the motor to spin in both counterclockwise and clockwise directions. Each stator is anchored to the peptidoglycan layer through the C-terminal periplasmic domain of MotB and acts as a proton channel to couple the proton flow through the channel with torque generation. Highly conserved charged residues at the rotor–stator interface are required not only for torque generation but also for stator assembly around the rotor. In this review, we will summarize our current understanding of the structure and function of the proton-driven bacterial flagellar motor.

  19. Impaired orofacial motor functions on chronic temporomandibular disorders.

    Science.gov (United States)

    Ferreira, Cláudia Lúcia Pimenta; Machado, Bárbara Cristina Zanandréa; Borges, Carina Giovana Pissinatti; Rodrigues Da Silva, Marco Antonio M; Sforza, Chiarella; De Felício, Cláudia Maria

    2014-08-01

    Because temporomandibular disorders (TMDs) rehabilitation continues to be a challenge, a more comprehensive picture of the orofacial functions in patients with chronic pain is required. This study assessed the orofacial functions, including surface electromyography (EMG) of dynamic rhythmic activities, in patients with moderate-severe signs and symptoms of chronic TMD. It was hypothesized that orofacial motor control differs between patients with moderate-severe chronic TMD and healthy subjects. Seventy-six subjects (46 with TMD and 30 control) answered questionnaires of severity of TMD and chewing difficulties. Orofacial functions and EMG during chewing were assessed. Standardized EMG indices were obtained by quantitative analysis of the differential EMG signals of the paired masseter and temporal muscles, and used to describe muscular action during chewing. TMD patients showed significant greater difficulty in chewing; worse orofacial scores; longer time for free mastication; a less accurate recruitment of the muscles on the working and balancing sides, reduced symmetrical mastication index (SMI) and increased standardized activity during EMG test than healthy subjects. SMI, TMD severity and orofacial myofunctional scores were correlated (Porofacial functions and increased activity of the muscles of balancing sides during unilateral chewing characterized the altered orofacial motor control in patients with moderate-severe chronic TMD. Implications for rehabilitation are discussed.

  20. 75 FR 41521 - Delphi Corporation, Automotive Holding Group, Plant 6, Currently Known as General Motors...

    Science.gov (United States)

    2010-07-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Delphi Corporation, Automotive Holding Group, Plant 6, Currently Known as General Motors Corporation Including On-Site Leased Workers From Securitas, EDS, Bartech, Mays Chemicals, Interim Physicians, LLC and HSS...

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

    Directory of Open Access Journals (Sweden)

    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.

  2. 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...

  3. Experimental Investigations on PV Powered SVM-DTC Induction Motor without AC Phase Current Sensors

    Directory of Open Access Journals (Sweden)

    T. Muthamizhan

    2014-05-01

    Full Text Available The paper presents a low-cost, phase-current reconstruction algorithm for space vector modulated direct torque controlled induction motor using the information obtained from only one shunt resistor which is in series with low side switches in a conventional three-phase inverter. The aim is to develop a low-cost high - performance induction motor drive. It uses the dc-link voltage and dc current to reconstruct the stator currents needed to estimate the motor flux and the electromagnetic torque. Photovoltaic arrays convert solar power to dc electric power; uses chopper and dc-ac inverter to fed three phase Induction Motor. The chopper used here is current fed full bridge boost dc-dc converter, which is preferred and extensively used in high voltage applications and advantageous over voltage fed converters. The inverter switches are controlled by PWM techniques obtained from SVM-DTC of IM. The experimental investigations are given to prove the ability of the proposed scheme of reproducing the performances of a SVM- DTC IM drive.

  4. 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.

  5. Differential sensitivity of cranial and limb motor function to nigrostriatal dopamine depletion.

    Science.gov (United States)

    Plowman, Emily K; Maling, Nicholas; Rivera, Benjamin J; Larson, Krista; Thomas, Nagheme J; Fowler, Stephen C; Manfredsson, Fredric P; Shrivastav, Rahul; Kleim, Jeffrey A

    2013-01-15

    The present study determined the differential effects of unilateral striatal dopamine depletion on cranial motor versus limb motor function. Forty male Long Evans rats were first trained on a comprehensive motor testing battery that dissociated cranial versus limb motor function and included: cylinder forepaw placement, single pellet reaching, vermicelli pasta handling; sunflower seed opening, pasta biting acoustics, and a licking task. Following baseline testing, animals were randomized to either a 6-hydroxydopamine (6-OHDA) (n=20) or control (n=20) group. Animals in the 6-OHDA group received unilateral intrastriatal 6-OHDA infusions to induce striatal dopamine depletion. Six-weeks following infusion, all animals were re-tested on the same battery of motor tests. Near infrared densitometry was performed on sections taken through the striatum that were immunohistochemically stained for tyrosine hydroxylase (TH). Animals in the 6-OHDA condition showed a mean reduction in TH staining of 88.27%. Although 6-OHDA animals were significantly impaired on all motor tasks, limb motor deficits were more severe than cranial motor impairments. Further, performance on limb motor tasks was correlated with degree of TH depletion while performance on cranial motor impairments showed no significant correlation. These results suggest that limb motor function may be more sensitive to striatal dopaminergic depletion than cranial motor function and is consistent with the clinical observation that therapies targeting the nigrostriatal dopaminergic system in Parkinson's disease are more effective for limb motor symptoms than cranial motor impairments. Published by Elsevier B.V.

  6. Sensory and Motor Peripheral Nerve Function and Incident Mobility Disability

    DEFF Research Database (Denmark)

    Ward, R. E.; Boudreau, R. M.; Caserotti, P.

    2014-01-01

    ObjectivesTo assess the relationship between sensorimotor nerve function and incident mobility disability over 10years. DesignProspective cohort study with longitudinal analysis. SettingTwo U.S. clinical sites. ParticipantsPopulation-based sample of community-dwelling older adults with no mobility...... disability at 2000/01 examination (N=1,680; mean age SD 76.52.9, body mass index 27.14.6; 50.2% female, 36.6% black, 10.7% with diabetes mellitus). MeasurementsMotor nerve conduction amplitude (poor...

  7. [The gastrointestinal motor function in irritable bowel syndrome (IBS)].

    Science.gov (United States)

    Sagami, Yasuhiro; Hongo, Michio

    2006-08-01

    Irritable bowel syndrome (IBS) is presumed to be a gastrointestinal motility disorder with the brain-gut interaction. Psychological stress and stimuli of the colonic lumen increase colonic motor function which is exaggerated in IBS patients. Corticotropin-releasing hormone (CRH) is considered to be a major mediator of stress responses in the brain-gut interaction. Similarly, peripheral administration of CRH affects colonic motility, induces abdominal symptoms and stimulates ACTH secretion, all of which are exaggerated in IBS patients. CRH antagonist blocks the greater responses of colonic motility in IBS. CRH is a key peptide in the pathophysiology of IBS with the brain-gut interaction.

  8. Optimization of brushless direct current motor design using an intelligent technique.

    Science.gov (United States)

    Shabanian, Alireza; Tousiwas, Armin Amini Poustchi; Pourmandi, Massoud; Khormali, Aminollah; Ataei, Abdolhay

    2015-07-01

    This paper presents a method for the optimal design of a slotless permanent magnet brushless DC (BLDC) motor with surface mounted magnets using an improved bee algorithm (IBA). The characteristics of the motor are expressed as functions of motor geometries. The objective function is a combination of losses, volume and cost to be minimized simultaneously. This method is based on the capability of swarm-based algorithms in finding the optimal solution. One sample case is used to illustrate the performance of the design approach and optimization technique. The IBA has a better performance and speed of convergence compared with bee algorithm (BA). Simulation results show that the proposed method has a very high/efficient performance.

  9. Ciliobrevins as Tools for Studying Dynein Motor Function

    Directory of Open Access Journals (Sweden)

    Douglas eRoossien

    2015-07-01

    Full Text Available Dyneins are a small class of molecular motors that bind to microtubules and walk towards their minus ends. They are essential for the transport and distribution of organelles, signaling complexes and cytoskeletal elements. In addition dyneins generate forces on microtubule arrays that power the beating of cilia and flagella, cell division, migration and growth cone motility. Classical approaches to the study of dynein function in axons involve the depletion of dynein, expression of mutant/truncated forms of the motor, or interference with accessory subunits. By necessity, these approaches require prolonged time period for the expression or manipulation of cellular dynein levels. With the discovery of the ciliobrevins, a class of cell permeable small molecule inhibitors of dynein, it is now possible to acutely disrupt dynein both globally and locally. In this review, we briefly summarize recent work using ciliobrevins to inhibit dynein and discuss the insights ciliobrevins have provided about dynein function in various cell types with a focus on neurons. We temper this with a discussion of the need for studies that will elucidate the mechanism of action of ciliobrevin and as well as the need for experiments to further analyze the specificity of ciliobreviens for dynein. Although much remains to be learned about ciliobrevins, these small molecules are proving themselves to be valuable novel tools to assess the cellular functions of dynein.

  10. Differential changes in the development of motor coordination and executive functions in children with motor coordination impairments.

    Science.gov (United States)

    Michel, Eva; Molitor, Sabine; Schneider, Wolfgang

    2016-09-13

    Cognitive and motor coordination skills of children with and without motor coordination impairments were examined with a one-year follow-up investigation. Initially, children were between 4 and 6 years old. Age-appropriate tests of executive functions (updating, switching, inhibition, interference control), motor coordination (the Movement Assessment Battery for Children-2) and fitness (the Körperkoordinations-Test für Kinder) were administered in two consecutive years. Several background variables (age, socioeconomic status, medical support, clinical interventions, leisure activities) and potential moderators (nonverbal intelligence, reaction time, visual perception) were controlled. The matched sample consisted of 48 control children and 48 children with motor coordination impairments. The children's executive functions dramatically improved during the one-year period. With regard to motor coordination performance, half of the impaired children caught up to the control children's level ("remission group"), while the remaining half showed no improvement ("persisting group"). Compared to the persisting group, the children in the remission group showed markedly better interference control at both measurement points. The correlation between executive functions and motor coordination is significant in the persisting group, but not in the remission group. The results of the study are discussed in the light of the role of executive functions, especially inhibition processes, for the automatization of motor coordination tasks.

  11. Current signature analysis for condition monitoring of cage induction motors industrial application and case histories

    CERN Document Server

    Thomson, William T

    2017-01-01

    This book has 13 chapters and contains a unique database of 50 industrial case histories on theapplication of MCSA to diagnose broken rotor bars or unacceptable levels of airgap eccentricity in cage induction motors with ratings from 127 kW (170 H.P.) to 10,160 kW (13,620 H.P.). There are also unsuccessful case histories which is another unique feature of the book. The case studies also illustrate the effects of mechanical load dynamics downstream of the motor on the interpretation of current signatures. A number of cases are presented where abnormal operation of the driven loadwas diagnosed.

  12. Motor network changes associated with successful motor skill relearning after acute ischemic stroke: a longitudinal functional magnetic resonance imaging study.

    Science.gov (United States)

    Askim, Torunn; Indredavik, Bent; Vangberg, Torgil; Håberg, Asta

    2009-01-01

    . Motor learning mechanisms may be operative in stroke recovery and possibly reinforced by rehabilitative training. . To assess early motor network changes after acute ischemic stroke in patients treated with very early mobilization and task-oriented physical therapy in a comprehensive stroke unit, to investigate the association between neuronal activity and improvements in hand function, and to qualitatively explore the changes in neuronal activity in relation to motor learning. . Patients were assessed by functional magnetic resonance imaging and by clinical tests within the first week after stroke and 3 months later. After discharge, all participants were offered functional training of the affected arm according to individual needs. . A total of 359 patients were screened, with 12 patients experiencing first-ever stroke, excluding primary sensorimotor cortex (MISI), with severe to moderately impaired hand function fulfilling the inclusion criteria. Laterality indexes (LIs) for MISI increase significantly during follow-up. There is increased cerebellar and striatal activation acutely, replaced by increased activation of ipsilesional MISI in the chronic phase. Bilateral somatosensory association areas and contralesional secondary somatosensory cortex (SII) area are also more active in the chronic phase. Activation of the latter region also correlates positively with improved hand function. . Restoration of hand function is associated with highly lateralized MISI. Activity in bilateral somatosensory association area and contralesional SII may represent cortical plasticity involved in successful motor recovery. The changes in motor activity between acute and chronic phases seem to correspond to a motor learning process.

  13. Memantine elicits spinal blockades of motor function, proprioception, and nociception in rats.

    Science.gov (United States)

    Chen, Yu-Wen; Chiu, Chong-Chi; Liu, Kuo-Sheng; Hung, Ching-Hsia; Wang, Jhi-Joung

    2015-12-01

    Although memantine blocks sodium currents and produces local skin anesthesia, spinal anesthesia with memantine is unknown. The purpose of the study was to evaluate the local anesthetic effect of memantine in spinal anesthesia and its comparison with a widely used local anesthetic lidocaine. After intrathecally injecting the rats with five doses of each drug, the dose-response curves of memantine and lidocaine were constructed. The potencies of the drugs and durations of spinal anesthetic effects on motor function, proprioception, and nociception were compared with those of lidocaine. We showed that memantine produced dose-dependent spinal blockades in motor function, proprioception, and nociception. On a 50% effective dose (ED50 ) basis, the rank of potency was lidocaine greater than memantine (P < 0.05 for the differences). At the equipotent doses (ED25 , ED50 , ED75 ), the block duration produced by memantine was longer than that produced by lidocaine (P < 0.05 for the differences). Memantine, but not lidocaine, displayed more sensory/nociceptive block than motor block. The preclinical data demonstrated that memantine is less potent than lidocaine, whereas memantine produces longer duration of spinal anesthesia than lidocaine. Memantine shows a more sensory-selective action over motor blockade.

  14. Differentiating functions of the lateral and medial prefrontal cortex in motor response inhibition.

    Science.gov (United States)

    H Rodrigo, Achala; Domenico, Stefano I Di; Ayaz, Hasan; Gulrajani, Sean; Lam, Jaeger; Ruocco, Anthony C

    2014-01-15

    The right inferior frontal gyrus is generally considered a critical region for motor response inhibition. Recent studies, however, suggest that the role of this cortical area in response inhibition may be overstated and that the contributions of other aspects of the prefrontal cortex are often overlooked. The current study used optical imaging to identify regions of the prefrontal cortex beyond the right inferior frontal gyrus which may serve to support motor response inhibition. Forty-three right-handed healthy adults completed a manual Go/No-Go task while evoked oxygenation of the prefrontal cortex was measured using 16-channel functional near-infrared spectroscopy. During motor response inhibition, the right inferior frontal gyrus, and to a lesser extent the homologous contralateral region, showed increased activation relative to a baseline task. Conversely, the medial prefrontal cortex was significantly deactivated, and the extent of reduced activity in this region was associated with fewer errors on the response inhibition task. These findings suggest a more substantial role of the left inferior frontal gyrus in response inhibition and possibly a distinct function of the middle frontal gyrus subserving error detection on manual motor control tasks.

  15. Bispectrum of stator phase current for fault detection of induction motor.

    Science.gov (United States)

    Treetrong, Juggrapong; Sinha, Jyoti K; Gu, Fengshu; Ball, Andrew

    2009-07-01

    A number of research studies has shown that faults in a stator or rotor generally show sideband frequencies around the mains frequency (50 Hz) and at higher harmonics in the spectrum of the Motor Current Signature Analysis (MCSA). However in the present experimental studies such observations have not been seen, but any fault either in the stator or the rotor may distort the sinusoidal response of the motor RPM and the mains frequency so the MCSA response may contain a number of harmonics of the motor RPM and the mains frequency. Hence the use of a higher order spectrum (HOS), namely the bispectrum of the MCSA has been proposed here because it relates both amplitude and phase of number of the harmonics in a signal. It has been observed that it not only detects early faults but also indicates the severity of the fault to some extent.

  16. 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.

  17. Effect of cerebrolysin on motor function restoration during medical rehabilitation

    Directory of Open Access Journals (Sweden)

    M. A. Kustova

    2016-01-01

    Full Text Available Ischemic stroke (IS is characterized by high prevalence, mortality, and disability rates. Therapy aimed to correct one biochemical or molecular stage of ischemic cell injury fails to treat stroke, suggesting that it is necessary to study multimodality therapy affecting several related pathophysiological components.The paper gives the January 2016 results of the randomized placebo-controlled multicenter study CARS that demonstrates the positive effect of cerebrolysin versus placebo according to the primary efficiency criterion, the Action Research Arm Test (ARAT scale, and total outcome 90 days after disease onset. The investigation enrolled mainly patients with moderate or severe IS (the mean National Institutes of Health Stroke Scale score was 9 at baseline.The specific features of the CARS study versus those of other clinical trials of neuroprotectors were the initial planning of narrower end criteria of efficiency (arm motor function recovery whereas the major goal of many investigations was to reduce mortality rates, as well as a standardized rehabilitation program in both treatment groups. Such investigations did not previously take into account the nature and volume of rehabilitation measures although the latter may have a substantial impact on the outcome of stroke.The CARS study is the first among the previously conducted clinical trials of neuroprotectors, which has attained the primary objective (to restore motor function, which opens up fresh opportunities for the medical support of rehabilitation measures in patients with IS.

  18. Direct current stimulation promotes BDNF-dependent synaptic plasticity: potential implications for motor learning.

    Science.gov (United States)

    Fritsch, Brita; Reis, Janine; Martinowich, Keri; Schambra, Heidi M; Ji, Yuanyuan; Cohen, Leonardo G; Lu, Bai

    2010-04-29

    Despite its increasing use in experimental and clinical settings, the cellular and molecular mechanisms underlying transcranial direct current stimulation (tDCS) remain unknown. Anodal tDCS applied to the human motor cortex (M1) improves motor skill learning. Here, we demonstrate in mouse M1 slices that DCS induces a long-lasting synaptic potentiation (DCS-LTP), which is polarity specific, NMDA receptor dependent, and requires coupling of DCS with repetitive low-frequency synaptic activation (LFS). Combined DCS and LFS enhance BDNF-secretion and TrkB activation, and DCS-LTP is absent in BDNF and TrkB mutant mice, suggesting that BDNF is a key mediator of this phenomenon. Moreover, the BDNF val66met polymorphism known to partially affect activity-dependent BDNF secretion impairs motor skill acquisition in humans and mice. Motor learning is enhanced by anodal tDCS, as long as activity-dependent BDNF secretion is in place. We propose that tDCS may improve motor skill learning through augmentation of synaptic plasticity that requires BDNF secretion and TrkB activation within M1.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Probing for hemispheric specialization for motor skill learning: a transcranial direct current stimulation study.

    Science.gov (United States)

    Schambra, Heidi M; Abe, Mitsunari; Luckenbaugh, David A; Reis, Janine; Krakauer, John W; Cohen, Leonardo G

    2011-08-01

    Convergent findings point to a left-sided specialization for the representation of learned actions in right-handed humans, but it is unknown whether analogous hemispheric specialization exists for motor skill learning. In the present study, we explored this question by comparing the effects of anodal transcranial direct current stimulation (tDCS) over either left or right motor cortex (M1) on motor skill learning in either hand, using a tDCS montage to better isolate stimulation to one hemisphere. Results were compared with those previously found with a montage more commonly used in the field. Six groups trained for three sessions on a visually guided sequential pinch force modulation task with their right or left hand and received right M1, left M1, or sham tDCS. A linear mixed-model analysis for motor skill showed a significant main effect for stimulation group (left M1, right M1, sham) but not for hand (right, left) or their interaction. Left M1 tDCS induced significantly greater skill learning than sham when hand data were combined, a result consistent not only with the hypothesized left hemisphere specialization for motor skill learning but also with possible increased left M1 responsiveness to tDCS. The unihemispheric montage effect size was one-half that of the more common montage, and subsequent power analysis indicated that 75 subjects per group would be needed to detect differences seen with only 12 subjects with the customary bihemispheric montage.

  1. Effect of Pinellia ternata Lectin on Membrane Currents of Mouse Motor Nerve Terminals

    Institute of Scientific and Technical Information of China (English)

    施玉樑; 徐幼芬; 张辉

    1994-01-01

    Pinellia ternata lectin (PTL) extracted from the fresh juice of rhizome of pinellia ternata used as a traditional Chinese medicine facilitated the quantal release of acetylcholine (ACh) in the mouse motor nerve terminals and formed cation channels in artificial lipid bilayer. Here we report the action of PTL on presynaptic membrane currents of motor nerve terminals.The experiments were performed on the intercostal nerve triangularis sterni muscle preparations. By means of the perineurial recording, the effects of PTL on the sodium current in the preterminal part , three potassium currents and two calcium currents generated from the nerve terminals were investigated. The results show that PTL increases voltage-dependent fast Ca2+ current (ICa,f), Na+ current (INa) and Ca2+-acti-vated K+ current (IK,Ca) without action on either the voltage-dependent fast K+ current (IK,f) or the slow K+ current (IK,S). These effects are irreversible, but can be reversed by mannan, the specific binding sugar for PTL.The to

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

    Directory of Open Access Journals (Sweden)

    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

  3. Effect of polymer additives on characteristics of direct-current motor with liquid dielectric filler

    Science.gov (United States)

    Ivanov, V. I.; Bashkatova, S. T.; Lubsanova, A. A.; Tokarev, S. B.; Zadaroshnaya, G. N.; Pastukhova, I. N.

    1984-11-01

    In d.c. motors filled with dielectric of the hydrocarbon kind hydrodynamic losses can constitute up to 40% of the total losses. Consequently, a study was made to determine the proper additive and amount to reduce the hydraulic drag without dehomogenizing the liquid filler over long operating periods. Two polymethacrylates, never before used for this application were selected. Two motors of different size, a 0.8 kW DPK and a 6 kW DPK, were tested in kerosene with 0.005-1.0 wt% of these additives. An evaluation of the data, including the hydraulic drag coefficient as a function of the Reynolds number and the temperature rise at critical motor components (armature winding in slots, armature endturns on drive side, armature teeth, liquid in interpolar space, field winding, pole pieces) with or without additive, has yielded the optimum range of additive concentration for each motor size. An evaluation of the heat transfer at critical surfaces, with the aid of dimensional analysis, has yielded the semiempirical relation Nu=CRe0.65Pr0.4Km (C- constant factor different for each surface, Km- constant factor with exponent different for each additive polymer materials). The results can be extended to transformer oil and diesel oil as liquid motor-filling medium.

  4. Transcranial direct current stimulation and EEG-based motor imagery BCI for upper limb stroke rehabilitation.

    Science.gov (United States)

    Ang, Kai Keng; Guan, Cuntai; Phua, Kok Soon; Wang, Chuanchu; Teh, Irvin; Chen, Chang Wu; Chew, Effie

    2012-01-01

    Clinical studies had shown that EEG-based motor imagery Brain-Computer Interface (MI-BCI) combined with robotic feedback is effective in upper limb stroke rehabilitation, and transcranial Direct Current Stimulation (tDCS) combined with other rehabilitation techniques further enhanced the facilitating effect of tDCS. This motivated the current clinical study to investigate the effects of combining tDCS with MI-BCI and robotic feedback compared to sham-tDCS for upper limb stroke rehabilitation. The stroke patients recruited were randomized to receive 20 minutes of tDCS or sham-tDCS prior to 10 sessions of 1-hour MI-BCI with robotic feedback for 2 weeks. The online accuracies of detecting motor imagery from idle condition were assessed and offline accuracies of classifying motor imagery from background rest condition were assessed from the EEG of the evaluation and therapy parts of the 10 rehabilitation sessions respectively. The results showed no evident differences between the online accuracies on the evaluation part from both groups, but the offline analysis on the therapy part yielded higher averaged accuracies for subjects who received tDCS (n=3) compared to sham-tDCS (n=2). The results suggest towards tDCS effect in modulating motor imagery in stroke, but a more conclusive result can be drawn when more data are collected in the ongoing study.

  5. Modeling and Simulation of Current Source Inverter Fed Synchronous Motor in Complex Frequency Domain Taking the Transition Zone From Induction Motor to Synchronous Motor Mode into Account

    OpenAIRE

    A.B. Chattopadhyay; Sunil Thomas

    2014-01-01

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

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

    OpenAIRE

    A.B. Chattopadhyay; Sunil Thomas

    2014-01-01

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

  7. Can Clinical Assessment of Locomotive Body Function Explain Gross Motor Environmental Performance in Cerebral Palsy?

    Science.gov (United States)

    Sanz Mengibar, Jose Manuel; Santonja-Medina, Fernando; Sanchez-de-Muniain, Paloma; Canteras-Jordana, Manuel

    2016-03-01

    Gross Motor Function Classification System has discriminative purposes but does not assess short-term therapy goals. Locomotion Stages (LS) classify postural body functions and independent activity components. Assessing the relation between Gross Motor Function Classification System level and Locomotion Stages will make us understand if clinical assessment can explain and predict motor environmental performance in cerebral palsy. A total of 462 children were assessed with both scales. High reliability and strong negative correlation (-0.908) for Gross Motor Function Classification System and Locomotion Stages at any age was found. Sensitivity was 83%, and specificity and positive predictive value were 100% within the same age range. Regression analysis showed detailed probabilities for the realization of the Gross Motor Function Classification System depending on the Locomotion Stages and the age group. Postural body function measure with Locomotion Stages is reliable, sensitive, and specific for gross motor function and able to predict environmental performance.

  8. 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.

  9. Fault diagnosis of motor drives using stator current signal analysis based on dynamic time warping

    Science.gov (United States)

    Zhen, D.; Wang, T.; Gu, F.; Ball, A. D.

    2013-01-01

    Electrical motor stator current signals have been widely used to monitor the condition of induction machines and their downstream mechanical equipment. The key technique used for current signal analysis is based on Fourier transform (FT) to extract weak fault sideband components from signals predominated with supply frequency component and its higher order harmonics. However, the FT based method has limitations such as spectral leakage and aliasing, leading to significant errors in estimating the sideband components. Therefore, this paper presents the use of dynamic time warping (DTW) to process the motor current signals for detecting and quantifying common faults in a downstream two-stage reciprocating compressor. DTW is a time domain based method and its algorithm is simple and easy to be embedded into real-time devices. In this study DTW is used to suppress the supply frequency component and highlight the sideband components based on the introduction of a reference signal which has the same frequency component as that of the supply power. Moreover, a sliding window is designed to process the raw signal using DTW frame by frame for effective calculation. Based on the proposed method, the stator current signals measured from the compressor induced with different common faults and under different loads are analysed for fault diagnosis. Results show that DTW based on residual signal analysis through the introduction of a reference signal allows the supply components to be suppressed well so that the fault related sideband components are highlighted for obtaining accurate fault detection and diagnosis results. In particular, the root mean square (RMS) values of the residual signal can indicate the differences between the healthy case and different faults under varying discharge pressures. It provides an effective and easy approach to the analysis of motor current signals for better fault diagnosis of the downstream mechanical equipment of motor drives in the time

  10. Extracting DC bus current information for optimal phase correction and current ripple in sensorless brushless DC motor drive

    Institute of Scientific and Technical Information of China (English)

    Zu-sheng HO; Chii-maw UANG; Ping-chieh WANG

    2014-01-01

    Brushless DC motor (BLDCM) sensorless driving technology is becoming increasingly established. However, op-timal phase correction still relies on complex calculations or algorithms. In finding the correct commutation point, the problem of phase lag is introduced. In this paper, we extract DC bus current information for auto-calibrating the phase shift to obtain the correct commutation point and optimize the control of BLDC sensorless driving. As we capture only DC bus current information, the original shunt resistor is used in the BLDCM driver and there is no need to add further current sensor components. Software processing using only simple arithmetic operations successfully accomplishes the phase correction. Experimental results show that the proposed method can operate accurately and stably at low or high speed, with light or heavy load, and is suitable for practical applications. This approach will not increase cost but will achieve the best performance/cost ratio and meet market expectations.

  11. Expanded functional coupling of subcortical nuclei with the motor resting-state network in multiple sclerosis.

    Science.gov (United States)

    Dogonowski, Anne-Marie; Siebner, Hartwig R; Sørensen, Per Soelberg; Wu, Xingchen; Biswal, Bharat; Paulson, Olaf B; Dyrby, Tim B; Skimminge, Arnold; Blinkenberg, Morten; Madsen, Kristoffer H

    2013-04-01

    Multiple sclerosis (MS) impairs signal transmission along cortico-cortical and cortico-subcortical connections, affecting functional integration within the motor network. Functional magnetic resonance imaging (fMRI) during motor tasks has revealed altered functional connectivity in MS, but it is unclear how much motor disability contributed to these abnormal functional interaction patterns. To avoid any influence of impaired task performance, we examined disease-related changes in functional motor connectivity in MS at rest. A total of 42 patients with MS and 30 matched controls underwent a 20-minute resting-state fMRI session at 3 Tesla. Independent component analysis was applied to the fMRI data to identify disease-related changes in motor resting-state connectivity. Patients with MS showed a spatial expansion of motor resting-state connectivity in deep subcortical nuclei but not at the cortical level. The anterior and middle parts of the putamen, adjacent globus pallidus, anterior and posterior thalamus and the subthalamic region showed stronger functional connectivity with the motor network in the MS group compared with controls. MS is characterised by more widespread motor connectivity in the basal ganglia while cortical motor resting-state connectivity is preserved. The expansion of subcortical motor resting-state connectivity in MS indicates less efficient funnelling of neural processing in the executive motor cortico-basal ganglia-thalamo-cortical loops.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  13. Clinical functional MRI of sensorimotor cortex using passive motor and sensory stimulation at 3 Tesla.

    Science.gov (United States)

    Blatow, Maria; Reinhardt, Julia; Riffel, Katharina; Nennig, Ernst; Wengenroth, Martina; Stippich, Christoph

    2011-08-01

    To establish a passive motor paradigm for clinical functional MRI (fMRI) that could be beneficial for patients with motor or attention deficits who are not able to perform active motor tasks. A novel standardized sensorimotor fMRI protocol was applied in 16 healthy volunteers at 3 Tesla (T) using active and passive motor tasks as well as sensory stimulation of hands and feet. Data analysis was carried out individually using a dynamic thresholding routine. Active motor tasks yielded time efficient and robust blood-oxygen-level-dependent (BOLD) signals in primary motor cortex. Noteworthy, it was possible to achieve equal activation levels within identical anatomical localization for passive and active motor tasks with these paradigms. Patients unable to perform active movements can benefit from paradigms with passive motor and sensory stimulation. Therefore, we recommend these paradigms for functional somatotopic mapping of the central region at 3T in clinical routine. Copyright © 2011 Wiley-Liss, Inc.

  14. Current and future resources for functional metagenomics.

    Science.gov (United States)

    Lam, Kathy N; Cheng, Jiujun; Engel, Katja; Neufeld, Josh D; Charles, Trevor C

    2015-01-01

    Functional metagenomics is a powerful experimental approach for studying gene function, starting from the extracted DNA of mixed microbial populations. A functional approach relies on the construction and screening of metagenomic libraries-physical libraries that contain DNA cloned from environmental metagenomes. The information obtained from functional metagenomics can help in future annotations of gene function and serve as a complement to sequence-based metagenomics. In this Perspective, we begin by summarizing the technical challenges of constructing metagenomic libraries and emphasize their value as resources. We then discuss libraries constructed using the popular cloning vector, pCC1FOS, and highlight the strengths and shortcomings of this system, alongside possible strategies to maximize existing pCC1FOS-based libraries by screening in diverse hosts. Finally, we discuss the known bias of libraries constructed from human gut and marine water samples, present results that suggest bias may also occur for soil libraries, and consider factors that bias metagenomic libraries in general. We anticipate that discussion of current resources and limitations will advance tools and technologies for functional metagenomics research.

  15. Current and future resources for functional metagenomics

    Directory of Open Access Journals (Sweden)

    Kathy Nguyen Lam

    2015-10-01

    Full Text Available Functional metagenomics is a powerful experimental approach for studying gene function, starting from the extracted DNA of mixed microbial populations. A functional approach relies on the construction and screening of metagenomic libraries – physical libraries that contain DNA cloned from environmental metagenomes. The information obtained from functional metagenomics can help in future annotations of gene function and serve as a complement to sequence-based metagenomics. In this Perspective, we begin by summarizing the technical challenges of constructing metagenomic libraries and emphasize their value as resources. We then discuss libraries constructed using the popular cloning vector, pCC1FOS, and highlight the strengths and shortcomings of this system, alongside possible strategies to maximize existing pCC1FOS-based libraries by screening in diverse hosts. Finally, we discuss the known bias of libraries constructed from human gut and marine water samples, present results that suggest bias may also occur for soil libraries, and consider factors that bias metagenomic libraries in general. We anticipate that discussion of current resources and limitations will advance tools and technologies for functional metagenomics research.

  16. The mirror therapy program enhances upper-limb motor recovery and motor function in acute stroke patients.

    Science.gov (United States)

    Lee, Myung Mo; Cho, Hwi-Young; Song, Chang Ho

    2012-08-01

    The purpose of this study was to evaluate the effects of the mirror therapy program on upper-limb motor recovery and motor function in patients with acute stroke. Twenty-six patients who had an acute stroke within 6 mos of study commencement were assigned to the experimental group (n = 13) or the control group (n = 13). Both experimental and control group members participated in a standard rehabilitation program, but only the experimental group members additionally participated in mirror therapy program, for 25 mins twice a day, five times a week, for 4 wks. The Fugl-Meyer Assessment, Brunnstrom motor recovery stage, and Manual Function Test were used to assess changes in upper-limb motor recovery and motor function after intervention. In upper-limb motor recovery, the scores of Fugl-Meyer Assessment (by shoulder/elbow/forearm items, 9.54 vs. 4.61; wrist items, 2.76 vs. 1.07; hand items, 4.43 vs. 1.46, respectively) and Brunnstrom stages for upper limb and hand (by 1.77 vs. 0.69 and 1.92 vs. 0.50, respectively) were improved more in the experimental group than in the control group (P mirror therapy program is an effective intervention for upper-limb motor recovery and motor function improvement in acute stroke patients. Additional research on mirror therapy program components, intensity, application time, and duration could result in it being used as a standardized form of hand rehabilitation in clinics and homes.

  17. 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.

  18. Design of Current Controller for Two Quadrant DC Motor Drive by Using Model Order Reduction Technique

    CERN Document Server

    Ramesh, K; Nirmalkumar, A; Gurusamy, G

    2010-01-01

    In this paper, design of current controller for a two quadrant DC motor drive was proposed with the help of model order reduction technique. The calculation of current controller gain with some approximations in the conventional design process is replaced by proposed model order reduction method. The model order reduction technique proposed in this paper gives the better controller gain value for the DC motor drive. The proposed model order reduction method is a mixed method, where the numerator polynomial of reduced order model is obtained by using stability equation method and the denominator polynomial is obtained by using some approximation technique preceded in this paper. The designed controllers responses were simulated with the help of MATLAB to show the validity of the proposed method.

  19. Diagnostics of an induction-motor rotor by the spectral analysis of stator currents

    Science.gov (United States)

    Weinreb, K.

    2013-12-01

    A method for achieving more efficient revealing and more unambiguous evaluation of various kinds of defects in the induction-motor (IM) rotor, which is based on changes occurring in the characteristic signs of the spectrum of the stator current, is presented. The results and analysis of measurements performed for artificially specified cases of faults in the rotor of a small-capacity IM are presented.

  20. 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 (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. PMID:25714437

  1. Physical activity, motor function, and white matter hyperintensity burden in healthy older adults.

    Science.gov (United States)

    Fleischman, Debra A; Yang, Jingyun; Arfanakis, Konstantinos; Arvanitakis, Zoe; Leurgans, Sue E; Turner, Arlener D; Barnes, Lisa L; Bennett, David A; Buchman, Aron S

    2015-03-31

    To test the hypothesis that physical activity modifies the association between white matter hyperintensity (WMH) burden and motor function in healthy older persons without dementia. Total daily activity (exercise and nonexercise physical activity) was measured for up to 11 days with actigraphy (Actical; Philips Respironics, Bend, OR) in 167 older adults without dementia participating in the Rush Memory and Aging Project. Eleven motor performances were summarized into a previously described global motor score. WMH volume was expressed as percent of intracranial volume. Linear regression models, adjusted for age, education, and sex, were performed with total WMH volume as the predictor and global motor score as the outcome. Terms for total daily physical activity and its interaction with WMH volume were then added to the model. Higher WMH burden was associated with lower motor function (p = 0.006), and total daily activity was positively associated with motor function (p = 0.002). Total daily activity modified the association between WMH and motor function (p = 0.007). WMH burden was not associated with motor function in persons with high activity (90th percentile). By contrast, higher WMH burden remained associated with lower motor function in persons with average (50th percentile; estimate = -0.304, slope = -0.133) and low (10th percentile; estimate = -1.793, slope = -0.241) activity. Higher levels of physical activity may reduce the effect of WMH burden on motor function in healthy older adults. © 2015 American Academy of Neurology.

  2. Gastrointestinal motor function in patients with portal hypertension

    DEFF Research Database (Denmark)

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

    2000-01-01

    rates were evaluated in all subjects by means of a gamma camera technique. The technique was also used to measure the frequency of antral contractions. RESULTS: No difference was observed in gastric mean emptying time or small-intestinal mean transit time of liquid and solid markers between patients...... and controls. After 24 h, however, the geometric center of the liquid marker had a more caudal localization in the colon of the patient group than in the controls (P = 0.04); that is, the patients had a faster colonic transit. No difference was found in the frequency of antral contractions 45 min after...... 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....

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

    OpenAIRE

    Thais Botossi Scalha; Erica Miyasaki; Núbia Maria Freire Vieira Lima; Guilherme Borges

    2011-01-01

    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 Di...

  4. Recovery of motor and cognitive function after cerebellar lesions in a songbird - Role of estrogens

    OpenAIRE

    Spence, RD; Zhen, Y.; White, S; Schlinger, BA; Day, LB

    2009-01-01

    In addition to its key role in complex motor function, the cerebellum is increasingly recognized to have a role in cognition. Songbirds are particularly good models for the investigation of motor and cognitive processes but little is known about the role of the songbird cerebellum in these processes. To explore cerebellar function in a songbird, we lesioned the cerebellum of adult female zebra finches and examined the effects on a spatial working memory task and on motor function during this ...

  5. Functional Connectivity in Amygdalar-Sensory/(Pre)Motor networks at rest: New evidence from the Human Connectome Project.

    Science.gov (United States)

    Toschi, Nicola; Duggento, Andrea; Passamonti, Luca

    2017-02-23

    The word "e-motion" derives from the Latin word "ex-moveo" which literally means "moving away from something / somebody". Emotions are thus fundamental to prime action and goal-directed behavior with obvious implications for individual's survival. However, the brain mechanisms underlying the interactions between emotional and motor cortical systems remain poorly understood. A recent diffusion tensor imaging study in humans has reported the existence of direct anatomical connections between the amygdala and sensory/(pre)motor cortices, corroborating an initial observation in animal research. Nevertheless, the functional significance of these amygdala-sensory/(pre)motor pathways remain uncertain. More specifically, it is currently unclear whether a distinct amygdala-sensory/(pre)motor circuit can be identified with resting-state functional magnetic resonance imaging (rs-fMRI). This is a key issue, as rs-fMRI offers an opportunity to simultaneously examine distinct neural circuits that underpin different cognitive, emotional, and motor functions, while minimizing task-related performance confounds. We therefore tested the hypothesis that the amygdala and sensory/(pre)motor cortices could be identified as part of the same resting-state functional connectivity network. To this end, we examined independent component analysis results in a very large rs-fMRI data-set drawn from the Human Connectome project (n=820 participants, mean age: 28.5 years). To our knowledge, we report for the first time the existence of a distinct amygdala-sensory/(pre)motor functional network at rest. rs-fMRI studies are now warranted to examine potential abnormalities in this circuit in psychiatric and neurological diseases that may be associated with alterations in the amygdala-sensory/(pre)motor pathways (e.g., conversion disorders, impulse control disorders, amyotrophic lateral sclerosis, and multiple sclerosis). This article is protected by copyright. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. How electrode montage affects transcranial direct current stimulation of the human motor cortex.

    Science.gov (United States)

    Salvador, Ricardo; Wenger, Cornelia; Nitsche, Michael A; Miranda, Pedro C

    2015-01-01

    Several different electrode configurations were originally proposed to induce excitability changes in the hand area of the motor cortex in transcranial direct current stimulation (tDCS). However only one was found to efficiently affect cortical excitability: anode/cathode over the primary motor cortex and return electrode placed over the contralateral orbit (M-CF configuration). In this work we used the finite element method to calculate the electric field (E-field) induced in a realistic human head model in all the proposed electrode configurations. In order to analyze the results, average values of the E-field's magnitude and polar/azimuthal angles were calculated in several cortical motor and premotor areas which may have an effect on the output of the primary motor cortex. The average E-field's magnitude at the hand-knob (HK) was similar between the M-CF configuration (0.16 V/m) and a few other tested configurations, the same happening for the average polar angle (129°). However this configuration achieved the highest mean E-field values over premotor (PM) areas (0.21 V/m). These results show that the polar angle and the average magnitude of the E-field evaluated at the HK and at the PM cortex might be important parameters in predicting the success of a specific electrode montage in tDCS.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Park, Eun-Young

    2016-06-01

    [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 frequency based on neurodevelopmental therapy for a period of 1 year. [Results] The correlation between physical therapy frequency and Gross Motor Function Measure scores for crawling and kneeling, standing, walking, running and jumping, and rolling, and the Gross Motor Function Measure total score was significant. The differences in gross motor function according to physical therapy frequency were significant for crawling, kneeling, standing, and Gross Motor Function Measure total score. The differences in gross motor function according to frequency of physical therapy were significant for standing in Gross Motor Function Classification System Level V. [Conclusion] Intensive physical therapy was more effective for improving gross motor function in children with cerebral palsy. In particular, crawling and kneeling, and standing ability showed greater increases with intensive physical therapy.

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

    Science.gov (United States)

    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 frequency based on neurodevelopmental therapy for a period of 1 year. [Results] The correlation between physical therapy frequency and Gross Motor Function Measure scores for crawling and kneeling, standing, walking, running and jumping, and rolling, and the Gross Motor Function Measure total score was significant. The differences in gross motor function according to physical therapy frequency were significant for crawling, kneeling, standing, and Gross Motor Function Measure total score. The differences in gross motor function according to frequency of physical therapy were significant for standing in Gross Motor Function Classification System Level V. [Conclusion] Intensive physical therapy was more effective for improving gross motor function in children with cerebral palsy. In particular, crawling and kneeling, and standing ability showed greater increases with intensive physical therapy. PMID:27390440

  11. COMPARISON THE EFFECT OF SIMULTANEOUS SENSORY STIMULATION AND CURRENT OCCUPATIONAL THERAPY APPROACHES ON MOTOR DEVELOPMENT OF THE INFANTS WITH DOWN SYNDROME

    Directory of Open Access Journals (Sweden)

    Hossein KARIMI

    2010-12-01

    Full Text Available ObjectiveNeuromuscular characteristics in Down syndrome result in generalized muscular hypotonia, developmental delays and sensory integration deficits. The aim of this study was to compare the effects of simultaneous sensory stimulations and current occupational therapy approaches on motor functions development of infants with Down syndrome.Materials & MethodsEighteen infants with Down syndrome, aged 6 -18 months, were evaluated in two groups: intervention group (simultaneous sensory stimulation and occupational therapy and control group (occupational therapy alone. They attended the program 3 times a week for 6 months and each session lasted 45 minutes. Motor functions were assessed before, during, and after intervention in the two groups, using GMFM test.ResultsMean motor function increased in both groups according to the GMFM test (P = 0.000. Comparison of the changes showed that although the mean difference of this variable was higher in the intervention group, the difference was not statistically significant (P = 0.576.Mean motor deficit reduced in both groups during the period of the study,which was statistically significant (P ConclusionEarly use of simultaneous sensory stimulations can improve the quality of motor skills in Down syndrome infants. It is suggested that it may be used as an early intervention in association with other methods in the rehabilitation of these patients. However, more studies in this regard are warranted.Keywords:Down syndrome, Motor development, Occupational therapy, Sensory stimulation.

  12. Current Developments in Nuclear Density Functional Methods

    CERN Document Server

    Dobaczewski, J

    2010-01-01

    Density functional theory (DFT) became a universal approach to compute ground-state and excited configurations of many-electron systems held together by an external one-body potential in condensed-matter, atomic, and molecular physics. At present, the DFT strategy is also intensely studied and applied in the area of nuclear structure. The nuclear DFT, a natural extension of the self-consistent mean-field theory, is a tool of choice for computations of ground-state properties and low-lying excitations of medium-mass and heavy nuclei. Over the past thirty-odd years, a lot of experience was accumulated in implementing, adjusting, and using the density-functional methods in nuclei. This research direction is still extremely actively pursued. In particular, current developments concentrate on (i) attempts to improve the performance and precision delivered by the nuclear density-functional methods, (ii) derivations of density functionals from first principles rooted in the low-energy chromodynamics and effective th...

  13. Motor Imagery-Based Rehabilitation: Potential Neural Correlates and Clinical Application for Functional Recovery of Motor Deficits after Stroke.

    Science.gov (United States)

    Tong, Yanna; Pendy, John T; Li, William A; Du, Huishan; Zhang, Tong; Geng, Xiaokun; Ding, Yuchuan

    2017-05-01

    Motor imagery (MI), defined as the mental implementation of an action in the absence of movement or muscle activation, is a rehabilitation technique that offers a means to replace or restore lost motor function in stroke patients when used in conjunction with conventional physiotherapy procedures. This article briefly reviews the concepts and neural correlates of MI in order to promote improved understanding, as well as to enhance the clinical utility of MI-based rehabilitation regimens. We specifically highlight the role of the cerebellum and basal ganglia, premotor, supplementary motor, and prefrontal areas, primary motor cortex, and parietal cortex. Additionally, we examine the recent literature related to MI and its potential as a therapeutic technique in both upper and lower limb stroke rehabilitation.

  14. 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.

  15. Pediatric aquatic therapy on motor function and enjoyment in children diagnosed with cerebral palsy of various motor severities.

    Science.gov (United States)

    Lai, Chih-Jou; Liu, Wen-Yu; Yang, Tsui-Fen; Chen, Chia-Ling; Wu, Ching-Yi; Chan, Rai-Chi

    2015-02-01

    This study investigates the effects of pediatric aquatic therapy on motor function, enjoyment, activities of daily living, and health-related quality of life for children with spastic cerebral palsy of various motor severities. Children with spastic cerebral palsy were assigned to a pediatric aquatic therapy group (n = 11; mean age = 85.0 ± 33.1 months; male : female = 4 : 7) or a control group (n = 13; mean age = 87.6 ± 34.0 months; male : female = 9 : 4). The statistic results indicate that the pediatric aquatic therapy group had greater average 66-item Gross Motor Function Measure following intervention than the control group (η(2) = 0.308, P = .007), even for children with Gross Motor Function Classification System level IV (5.0 vs 1.3). The pediatric aquatic therapy group had higher Physical Activity Enjoyment Scale scores than the control group at post-treatment (P = .015). These findings demonstrate that pediatric aquatic therapy can be an effective and alternative therapy for children with cerebral palsy even with poor Gross Motor Function Classification System level.

  16. Structure and Function Study of Phi29 DNA packaging motor

    Science.gov (United States)

    Fang, Huaming

    molecules were required to bind to one short dsDNA molecule. The inhibitive curve of Walker B mutant gp16 analyzed by binomial distribution model showed that one inactive mutant gp16 in the gp16 ring could block the function of the motor and the stoichiometry of gp16 was six. These findings facilitate our understanding of the molecular mechanism of viral DNA packaging: a novel viral DNA packaging model "push through a one-way valve" was proposed. In this model, the connector functioned as a valve to allow DNA to enter but prevented it from sliding out during DNA packaging; the six subunits in the gp16 ring acted sequentially to push DNA into the connector channel. ATP binding of gp16 induced a conformation change with a high affinity for dsDNA. Then, the ATP was hydrolyzed which resulted in the movement of subdomains in this individual gp16 subunit and DNA was pushed forward, followed by the double helix of dsDNA being brought forward to the adjacent subunit in the gp16 ring. The elucidation of the viral DNA packaging mechanism holds great potential for developing artificial motors for delivering drugs and other molecular cargos.

  17. Classification of motor imagery by means of cortical current density estimation and Von Neumann entropy.

    Science.gov (United States)

    Kamousi, Baharan; Amini, Ali Nasiri; He, Bin

    2007-06-01

    The goal of the present study is to employ the source imaging methods such as cortical current density estimation for the classification of left- and right-hand motor imagery tasks, which may be used for brain-computer interface (BCI) applications. The scalp recorded EEG was first preprocessed by surface Laplacian filtering, time-frequency filtering, noise normalization and independent component analysis. Then the cortical imaging technique was used to solve the EEG inverse problem. Cortical current density distributions of left and right trials were classified from each other by exploiting the concept of Von Neumann entropy. The proposed method was tested on three human subjects (180 trials each) and a maximum accuracy of 91.5% and an average accuracy of 88% were obtained. The present results confirm the hypothesis that source analysis methods may improve accuracy for classification of motor imagery tasks. The present promising results using source analysis for classification of motor imagery enhances our ability of performing source analysis from single trial EEG data recorded on the scalp, and may have applications to improved BCI systems.

  18. A New High Speed Induction Motor Drive based on Field Orientation and Hysteresis Current Comparison

    Science.gov (United States)

    Ogbuka, Cosmas; Nwosu, Cajethan; Agu, Marcel

    2016-09-01

    This paper presents a new high speed induction motor drive based on the core advantage of field orientation control (FOC) and hysteresis current comparison (HCC). A complete closed loop speed-controlled induction motor drive system is developed consisting of an outer speed and an inner HCC algorithm which are optimised to obtain fast and stable speed response with effective current and torque tracking, both during transient and steady states. The developed model, being speed-controlled, was examined with step and ramp speed references and excellent performances obtained under full load stress. A speed response comparison of the model with the standard AC3 (Field-Oriented Control Induction Motor Drive) of MATLAB Simpower systems shows that the model achieved a rise time of 0.0762 seconds compared to 0.2930 seconds achieved by the AC3. Also, a settle time of 0.0775 seconds was obtained with the developed model while that of the AC3 model is 0.2986 seconds confirming, therefore, the superiority of the developed model over the AC3 model which, hitherto, served as a reference standard.

  19. Differential Light Chain Assembly Influences Outer Arm Dynein Motor Function

    Science.gov (United States)

    DiBella, Linda M.; Gorbatyuk, Oksana; Sakato, Miho; Wakabayashi, Ken-ichi; Patel-King, Ramila S.; Pazour, Gregory J.; Witman, George B.; King, Stephen M.

    2005-01-01

    Tctex1 and Tctex2 were originally described as potential distorters/sterility factors in the non-Mendelian transmission of t-haplotypes in mice. These proteins have since been identified as subunits of cytoplasmic and/or axonemal dyneins. Within the Chlamydomonas flagellum, Tctex1 is a subunit of inner arm I1. We have now identified a second Tctex1-related protein (here termed LC9) in Chlamydomonas. LC9 copurifies with outer arm dynein in sucrose density gradients and is missing only in those strains completely lacking this motor. Zero-length cross-linking of purified outer arm dynein indicates that LC9 interacts directly with both the IC1 and IC2 intermediate chains. Immunoblot analysis revealed that LC2, LC6, and LC9 are missing in an IC2 mutant strain (oda6-r88) that can assemble outer arms but exhibits significantly reduced flagellar beat frequency. This defect is unlikely to be due to lack of LC6, because an LC6 null mutant (oda13) exhibits only a minor swimming abnormality. Using an LC2 null mutant (oda12-1), we find that although some outer arm dynein components assemble in the absence of LC2, they are nonfunctional. In contrast, dyneins from oda6-r88, which also lack LC2, retain some activity. Furthermore, we observed a synthetic assembly defect in an oda6-r88 oda12-1 double mutant. These data suggest that LC2, LC6, and LC9 have different roles in outer arm assembly and are required for wild-type motor function in the Chlamydomonas flagellum. PMID:16195342

  20. 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.

  1. Parameter Estimation of Inverter and Motor Model at Standstill using Measured Currents Only

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Knudsen, Morten; Tønnes, M.

    1996-01-01

    Methods for estimation of the parameters in the electrical equivalent diagram for the induction motor, based on special designed experiments, are given. In all experriments two of the three phases are given the same potential, i.e., no net torque is generatedand the motor is at standstill. Input...... to the system is the reference values for the stator voltages given as duty cycles for the Pulse With Modulated power device. The system output is the measured stator currents. Three experiments are describedgiving respectively 1) the stator resistance and inverter parameters, 2) the stator transient inductance...... and 3) the referred rotor rotor resistance and magnetizing inductance. The method developed in the two last experiments is independent of the inverter nonlinearity. New methods for system identification concerning saturation of the magnetic flux are given and a reference value for the flux level...

  2. Non-invasive brain stimulation: enhancing motor and cognitive functions in healthy old subjects

    Directory of Open Access Journals (Sweden)

    Maximo Zimerman

    2010-12-01

    Full Text Available Healthy aging is accompanied by changes in cognitive and motor functions that result in impairment of activities of daily living. This process involves a number of modifications in the brain and is associated with metabolic, structural and physiological changes; some of these serving as adaptive responses to the functional declines. Up to date there are no universally accepted strategies to ameliorate declining functions in this population. An essential basis to develop such strategies is a better understanding of neuroplastic changes during healthy aging. In this context, non-invasive brain stimulation techniques, such as transcranial direct current or transcranial magnetic stimulation, provide an attractive option to modulate cortical neuronal assemblies, even with subsequent changes in neuroplasticity. Thus, in the present review we discuss the use of these techniques as a tool to study underlying cortical mechanisms during healthy aging and as an interventional strategy to enhance declining functions and learning abilities in aged subjects.

  3. Embedding dual function into molecular motors through collective motion.

    Science.gov (United States)

    Saito, Nen; Kaneko, Kunihiko

    2017-03-10

    Protein motors, such as kinesins and dyneins, bind to a microtubule and travel along it in a specific direction. Previously, it was thought that the directionality for a given motor was constant in the absence of an external force. However, the directionality of the kinesin-5 Cin8 was recently found to change as the number of motors that bind to the same microtubule is increased. Here, we introduce a simple mechanical model of a microtubule-sliding assay in which multiple motors interact with the filament. We show that, due to the collective phenomenon, the directionality of the motor changes (e.g., from minus- to plus- end directionality), depending on the number of motors. This is induced by a large diffusive component in the directional walk and by the subsequent frustrated motor configuration, in which multiple motors pull the filament in opposite directions, similar to a game of tug-of-war. A possible role of the dual-directional motors for the mitotic spindle formation is also discussed. Our framework provides a general mechanism to embed two conflicting tasks into a single molecular machine, which works context-dependently.

  4. 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......: 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....... Motor performance is influenced by thigh muscle strength and is less dependent of respiratory capacity in our cohort of ambulatory patients © 2013 Wiley Periodicals, Inc....

  5. Differences of respiratory function according to level of the gross motor function classification system in children with cerebral palsy.

    Science.gov (United States)

    Kwon, Yong Hyun; Lee, Hye Young

    2014-03-01

    [Purpose] The current study was designed to investigate the difference in lung capacity and muscle strengthening related to respiration depending on the level of the Gross Motor Function Classification System (GMFCS) in children with cerebral palsy (CP) through tests of respiratory function and respiratory pressure. [Subjects and Methods] A total of 49 children with CP who were classified as below level III of the GMFCS were recruited for this study. They were divided into three groups (i.e., GMFCS level I, GMFCS level II, and GMFCS level III). All children took the pulmonary function test (PFT) and underwent respiratory pressure testing for assessment of respiratory function in terms of lung capacity and respiratory muscle strength. [Results] The GMFCS level III group showed significantly lower scores for all tests of the PFT (i.e., forced vital capacity (FVC), forced expiratory volume at one second (FEV1), and slow vital capacity (SVC)) and testing for respiratory pressures (maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP)) compared with the other two groups. The results of post hoc analysis indicated that the GMFCS level III group differed significantly from the other two groups in terms of FVC, FEV1, MIP, and MEP. In addition, a significant difference in SVC was observed between GMFCS level II and III. [Conclusion] Children with CP who had relatively low motor function showed poor pulmonary capacity and respiratory muscle weakness. Therefore, clinical manifestations regarding lung capacity and respiratory muscle will be required in children with CP who demonstrate poor physical activity.

  6. Motor imagery after subcortical stroke: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Sharma, Nikhil; Simmons, Lucy H; Jones, P Simon; Day, Diana J; Carpenter, T Adrian; Pomeroy, Valerie M; Warburton, Elizabeth A; Baron, Jean-Claude

    2009-04-01

    In recovered subcortical stroke, the pattern of motor network activation during motor execution can appear normal or not, depending on the task. Whether this applies to other aspects of motor function is unknown. We used functional MRI to assess motor imagery (MI), a promising new approach to improve motor function after stroke, and contrasted it to motor execution. Twenty well-recovered patients with hemiparetic subcortical stroke (14 males; mean age, 66.5 years) and 17 aged-matched control subjects were studied. Extensive behavioral screening excluded 8 patients and 4 control subjects due to impaired MI abilities. Subjects performed MI and motor execution of a paced finger-thumb opposition sequence using a functional MRI paradigm that monitored compliance. Activation within the primary motor cortex (BA4a and 4p), dorsal premotor, and supplementary motor areas was examined. The pattern of activation during affected-hand motor execution was not different from control subjects. Affected-hand MI activation was also largely similar to control subjects, including involvement of BA4, but with important differences: (1) unlike control subjects and the nonaffected hand, activation in BA4a and dorsal premotor was not lower during MI as compared with motor execution; (2) the hemispheric balance of BA4p activation was significantly less lateralized than control subjects; and (3) ipsilesional BA4p activation positively correlated with motor performance. In well-recovered subcortical stroke, the motor system, including ipsilesional BA4, is activated during MI despite the lesion. It, however, remains disorganized in proportion to residual motor impairment. Thus, components of movement upstream from execution appear differentially affected after stroke and could be targeted by rehabilitation in more severely affected patients.

  7. Effects of intermittent binge alcohol exposure on long-term motor function in young rats.

    Science.gov (United States)

    Forbes, Ashley; Cooze, Jared; Malone, Craig; French, Vanessa; Weber, John T

    2013-03-01

    Ethanol has well described acute effects on motor function, and chronic alcoholism can damage the cerebellum, which is associated with motor coordination, as well as motor learning. Binge drinking is common among preadolescents and adolescents, and this type of ethanol exposure may lead to long-term nervous system damage. In the current study, we analyzed the effects of periadolsecent/adolescent ethanol exposure on motor function in both male and female Sprague-Dawley rats. To simulate binge drinking, animals received an intraperitoneal injection of 25% (v/v) ethanol (3 g/kg) on postnatal days (PND) 25, 26, 29, 30, 33, 34, 37 and 38. On PND 42 and PND 61 animals were tested on their ability to traverse both square and round beams. There were no significant differences in the time to traverse the beams, or the amount of foot slips, between treated and untreated animals. On PND 48 and PND 62, animals were tested using a horizontal ladder walking apparatus. On PND 48 there were no differences in the ability of treated and untreated animals to traverse the ladder. On PND 62, there were no differences in the time to traverse the ladder, but ethanol treated animals had more foot slips than controls. On PND 43, we conducted footprint analysis of control and treated animals, which included measurements of stride length, paw overlap, and angle of foot placement. There was a significant difference in the angle of foot placement between treated and control animals, and this finding was significant for both male and female animals. There was also a significant overall difference in paw overlap between treatment groups. Although this effect was manifested in male animals there was no significant difference in females. These findings suggest that adolescent ethanol exposure can produce long-lasting effects on motor coordination, and that overall, effects are similar in males and females. In a second set of experiments, male rats received i.p. ethanol (3 g/kg) for 7 days (P31

  8. Muscle-Derived GDNF: A Gene Therapeutic Approach for Preserving Motor Neuron Function in ALS

    Science.gov (United States)

    2015-08-01

    AWARD NUMBER: W81XWH-14-1-0189 TITLE: Muscle -Derived GDNF: A Gene Therapeutic Approach for Preserving Motor Neuron Function in ALS PRINCIPAL...NUMBER W81XWH-14-1-0189 Muscle -Derived GDNF: A Gene Therapeutic Approach for Preserving Motor Neuron Function in ALS 5b. GRANT NUMBER 5c. PROGRAM...ALS) is characterized by the progressive degeneration of motor neurons leading to skeletal muscle atrophy, paralysis, and the death of patients

  9. Electrophysiological and functional connectivity of the human supplementary motor area.

    Science.gov (United States)

    Narayana, Shalini; Laird, Angela R; Tandon, Nitin; Franklin, Crystal; Lancaster, Jack L; Fox, Peter T

    2012-08-01

    Neuro-imaging methods for detecting functional and structural inter-regional connectivity are in a rapid phase of development. While reports of regional connectivity patterns based on individual methods are becoming common, studies comparing the results of two or more connectivity-mapping methods remain rare. In this study, we applied transcranial magnetic stimulation during PET imaging (TMS/PET), a stimulation-based method, and meta-analytic connectivity modeling (MACM), a task-based method to map the connectivity patterns of the supplementary motor area (SMA). Further, we drew upon the behavioral domain meta-data of the BrainMap® database to characterize the behavioral domain specificity of two maps. Both MACM and TMS/PET detected multi-synaptic connectivity patterns, with the MACM-detected connections being more extensive. Both MACM and TMS/PET detected connections belonging to multiple behavioral domains, including action, cognition and perception. Finally, we show that the two connectivity-mapping methods are complementary in that, the MACM informed on the functional nature of SMA connections, while TMS/PET identified brain areas electrophysiologically connected with the SMA. Thus, we demonstrate that integrating multimodal database and imaging techniques can derive comprehensive connectivity maps of brain areas.

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

    Science.gov (United States)

    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

  11. Detection of stator winding faults in induction motors using three-phase current monitoring.

    Science.gov (United States)

    Sharifi, Rasool; Ebrahimi, Mohammad

    2011-01-01

    The objective of this paper is to propose a new method for the detection of inter-turn short circuits in the stator windings of induction motors. In the previous reported methods, the supply voltage unbalance was the major difficulty, and this was solved mostly based on the sequence component impedance or current which are difficult to implement. Some other methods essentially are included in the offline methods. The proposed method is based on the motor current signature analysis and utilizes three phase current spectra to overcome the mentioned problem. Simulation results indicate that under healthy conditions, the rotor slot harmonics have the same magnitude in three phase currents, while under even 1 turn (0.3%) short circuit condition they differ from each other. Although the magnitude of these harmonics depends on the level of unbalanced voltage, they have the same magnitude in three phases in these conditions. Experiments performed under various load, fault, and supply voltage conditions validate the simulation results and demonstrate the effectiveness of the proposed technique. It is shown that the detection of resistive slight short circuits, without sensitivity to supply voltage unbalance is possible.

  12. Design and control of the phase current of a brushless dc motor to eliminate cogging torque

    Science.gov (United States)

    Jang, G. H.; Lee, C. J.

    2006-04-01

    This paper presents a design and control method of the phase current to reduce the torque ripple of a brushless dc (BLDC) motor by eliminating cogging torque. The cogging torque is the main source of torque ripple and consequently of speed error, and it is also the excitation source to generate the vibration and noise of a motor. This research proposes a modified current wave form, which is composed of main and auxiliary currents. The former is the conventional current to generate the commutating torque. The latter generates the torque with the same magnitude and opposite sign of the corresponding cogging torque at the given position in order to eliminate the cogging torque. Time-stepping finite element method simulation considering pulse-width-modulation switching method has been performed to verify the effectiveness of the proposed method, and it shows that this proposed method reduces torque ripple by 36%. A digital-signal-processor-based controller is also developed to implement the proposed method, and it shows that this proposed method reduces the speed ripple significantly.

  13. Enhancing motor performance improvement by personalizing non-invasive cortical stimulation with concurrent functional near-infrared spectroscopy and multi-modal motor measurements

    Science.gov (United States)

    Khan, Bilal; Hodics, Timea; Hervey, Nathan; Kondraske, George; Stowe, Ann; Alexandrakis, George

    2015-03-01

    Transcranial direct current stimulation (tDCS) is a non-invasive cortical stimulation technique that can facilitate task specific plasticity that can improve motor performance. Current tDCS interventions uniformly apply a chosen electrode montage to a subject population without personalizing electrode placement for optimal motor gains. We propose a novel perturbation tDCS (ptDCS) paradigm for determining a personalized electrode montage in which tDCS intervention yields maximal motor performance improvements during stimulation. PtDCS was applied to ten healthy adults and five stroke patients with upper hemiparesis as they performed an isometric wrist flexion task with their non-dominant arm. Simultaneous recordings of torque applied to a stationary handle, muscle activity by electromyography (EMG), and cortical activity by functional near-infrared spectroscopy (fNIRS) during ptDCS helped interpret how cortical activity perturbations by any given electrode montage related to changes in muscle activity and task performance quantified by a Reaction Time (RT) X Error product. PtDCS enabled quantifying the effect on task performance of 20 different electrode pair montages placed over the sensorimotor cortex. Interestingly, the electrode montage maximizing performance in all healthy adults did not match any of the ones being explored in current literature as a means of improving the motor performance of stroke patients. Furthermore, the optimal montage was found to be different in each stroke patient and the resulting motor gains were very significant during stimulation. This study supports the notion that task-specific ptDCS optimization can lend itself to personalizing the rehabilitation of patients with brain injury.

  14. Effector-independent reduction in choice reaction time following bi-hemispheric transcranial direct current stimulation over motor cortex

    Science.gov (United States)

    Drummond, Neil M.; Hayduk-Costa, Gabrielle; Leguerrier, Alexandra

    2017-01-01

    Increased reaction times (RT) during choice-RT tasks stem from a requirement for additional processing as well as reduced motor-specific preparatory activation. Transcranial direct current stimulation (tDCS) can modulate primary motor cortex excitability, increasing (anodal stimulation) or decreasing (cathodal stimulation) excitability in underlying cortical tissue. The present study investigated whether lateralized differences in choice-RT would result from the concurrent modulation of left and right motor cortices using bi-hemispheric tDCS. Participants completed a choice-RT task requiring either a left or right wrist extension. In forced-choice trials an illuminated target indicated the required response, whereas in free-choice trials participants freely selected either response upon illumination of a central fixation. Following a pre-test trial block, offline bi-hemispheric tDCS (1 mA) was applied over the left and right motor cortices for 10 minutes, which was followed by a post-tDCS block of RT trials. Twelve participants completed three experimental sessions, two with real tDCS (anode right, anode left), as well as a sham tDCS session. Post-tDCS results showed faster RTs for both right and left responses irrespective of tDCS polarity during forced-choice trials, while sham tDCS had no effect. In contrast, no stimulation-related RT or response selection differences were observed in free-choice trials. The present study shows evidence of an effector-independent speeding of response initiation in a forced-choice RT task following bi-hemispheric tDCS and yields novel information regarding the functional effect of bi-hemispheric tDCS. PMID:28263998

  15. Differentiation of motor cortical representation of hand muscles by navigated mapping of optimal TMS current directions in healthy subjects.

    Science.gov (United States)

    Bashir, Shahid; Perez, Jennifer M; Horvath, Jared C; Pascual-Leone, Alvaro

    2013-08-01

    The precision of navigated transcranial magnetic stimulation (TMS) to map the human primary motor cortex may be effected by the direction of TMS-induced current in the brain as determined by the orientation of the stimulation coil. In this study, the authors investigated the effect of current directionality on motor output mapping using navigated brain stimulation. The goal of this study was to determine the optimal coil orientation (and, thus, induced brain current) to activate hand musculature representations relative to each subject's unique neuroanatomical landmarks. The authors studied motor output maps for the first dorsal interosseous, abductor pollicis brevis, and abductor digiti minimi muscles in 10 normal volunteers. Monopolar current pulses were delivered through a figure-of-eight-shaped TMS coil, and motor evoked potentials were recorded using electromyography. At each targeted brain region, the authors systematically rotated the TMS coil to determine the direction of induced current in the brain for induction of the largest motor evoked potentials. These optimal current directions were expressed as an angle relative to each subject's central sulcus. Consistency of the optimal current direction was assessed by repeating the entire mapping procedure on two different occasions across subjects. The authors demonstrate that systematic optimization of current direction as guided by MRI-based neuronavigation improves the resolution of cortical output motor mapping with TMS.

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

    Science.gov (United States)

    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

  17. Transcranial direct current stimulation facilitates motor learning post-stroke: a systematic review and meta-analysis.

    Science.gov (United States)

    Kang, Nyeonju; Summers, Jeffery J; Cauraugh, James H

    2016-04-01

    Transcranial direct current stimulation (tDCS) is an attractive protocol for stroke motor recovery. The current systematic review and meta-analysis investigated the effects of tDCS on motor learning post-stroke. Specifically, we determined long-term learning effects by examining motor improvements from baseline to at least 5 days after tDCS intervention and motor practise. 17 studies reported long-term retention testing (mean retention interval=43.8 days; SD=56.6 days) and qualified for inclusion in our meta-analysis. Assessing primary outcome measures for groups that received tDCS and motor practise versus sham control groups created 21 valid comparisons: (1) 16 clinical assessments and (2) 5 motor skill acquisition tests. A random effects model meta-analysis showed a significant overall effect size=0.59 (pstimulation protocols: anodal on the ipsilesional hemisphere, cathodal on the contralesional hemisphere, or bilateral; (2) recovery stage: subacute or chronic stroke; (3) stimulation timing: tDCS before or during motor practise; and (4) task-specific training or conventional rehabilitation protocols. This robust meta-analysis identified novel long-term motor learning effects with tDCS and motor practise post-stroke.

  18. Control of rotor function in light-driven molecular motors

    NARCIS (Netherlands)

    Lubbe, Anouk S.; Ruangsupapichat, Nopporn; Caroli, Giuseppe; Feringa, Ben L.

    2011-01-01

    A study is presented on the control of rotary motion of an appending rotor unit in a light-driven molecular motor. Two new light driven molecular motors were synthesized that contain aryl groups connected to the stereogenic centers. The aryl groups behave as bidirectional free rotors in three of the

  19. Dissociated functional connectivity profiles for motor and attention deficits in acute right-hemisphere stroke.

    Science.gov (United States)

    Baldassarre, Antonello; Ramsey, Lenny; Rengachary, Jennifer; Zinn, Kristi; Siegel, Joshua S; Metcalf, Nicholas V; Strube, Michael J; Snyder, Abraham Z; Corbetta, Maurizio; Shulman, Gordon L

    2016-07-01

    Strokes often cause multiple behavioural deficits that are correlated at the population level. Here, we show that motor and attention deficits are selectively associated with abnormal patterns of resting state functional connectivity in the dorsal attention and motor networks. We measured attention and motor deficits in 44 right hemisphere-damaged patients with a first-time stroke at 1-2 weeks post-onset. The motor battery included tests that evaluated deficits in both upper and lower extremities. The attention battery assessed both spatial and non-spatial attention deficits. Summary measures for motor and attention deficits were identified through principal component analyses on the raw behavioural scores. Functional connectivity in structurally normal cortex was estimated based on the temporal correlation of blood oxygenation level-dependent signals measured at rest with functional magnetic resonance imaging. Any correlation between motor and attention deficits and between functional connectivity in the dorsal attention network and motor networks that might spuriously affect the relationship between each deficit and functional connectivity was statistically removed. We report a double dissociation between abnormal functional connectivity patterns and attention and motor deficits, respectively. Attention deficits were significantly more correlated with abnormal interhemispheric functional connectivity within the dorsal attention network than motor networks, while motor deficits were significantly more correlated with abnormal interhemispheric functional connectivity patterns within the motor networks than dorsal attention network. These findings indicate that functional connectivity patterns in structurally normal cortex following a stroke link abnormal physiology in brain networks to the corresponding behavioural deficits. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please

  20. 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 GMF

  1. 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 t

  2. Motor function measure: validation of a short form for young children with neuromuscular diseases.

    Science.gov (United States)

    de Lattre, Capucine; Payan, Christine; Vuillerot, Carole; Rippert, Pascal; de Castro, Denis; Bérard, Carole; Poirot, Isabelle

    2013-11-01

    To validate a useful version of the Motor Function Measure (MFM) in children with neuromuscular diseases aged .90), and discriminant validity was good. The MFM-20 can be used as an outcome measure for assessment of motor function in young children with neuromuscular disease. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  3. Effect of a nicotinic acetylcholine receptor agonists and antagonists on motor function in mice

    Science.gov (United States)

    Nicotinic acetylcholine receptors (nAChR) are ligand-gated cation channels found throughout the body, and serve to mediate diverse physiological functions. Muscle-type nAChR located in the motor endplate region of muscle fibers play an integral role in muscle contraction and thus motor function. The...

  4. A Phase Current Reconstruction Approach for Three-Phase Permanent-Magnet Synchronous Motor Drive

    Directory of Open Access Journals (Sweden)

    Hao Yan

    2016-10-01

    Full Text Available Three-phase permanent-magnet synchronous motors (PMSMs are widely used in renewable energy applications such as wind power generation, tidal energy and electric vehicles owing to their merits such as high efficiency, high precision and high reliability. To reduce the cost and volume of the drive system, techniques of reconstructing three-phase current using a single current sensor have been reported for three-phase alternating current (AC control system using the power converts. In existing studies, the reconstruction precision is largely influenced by reconstructing dead zones on the Space Vector Pulse Width Modulation (SVPWM plane, which requires other algorithms to compensate either by modifying PWM modulation or by phase-shifting of the PWM signal. In this paper, a novel extended phase current reconstruction approach for PMSM drive is proposed. Six novel installation positions are obtained by analyzing the sampling results of the current paths between each two power switches. By arranging the single current sensor at these positions, the single current sensor is sampled during zero voltage vectors (ZVV without modifying the PWM signals. This proposed method can reconstruct the three-phase currents without any complex algorithms and is available in the sector boundary region and low modulation region. Finally, this method is validated by experiments.

  5. Motor Cortex and Motor Cortical Interhemispheric Communication in Walking After Stroke: The Roles of Transcranial Magnetic Stimulation and Animal Models in Our Current and Future Understanding.

    Science.gov (United States)

    Charalambous, Charalambos C; Bowden, Mark G; Adkins, DeAnna L

    2016-01-01

    Despite the plethora of human neurophysiological research, the bilateral involvement of the leg motor cortical areas and their interhemispheric interaction during both normal and impaired human walking is poorly understood. Using transcranial magnetic stimulation (TMS), we have expanded our understanding of the role upper-extremity motor cortical areas play in normal movements and how stroke alters this role, and probed the efficacy of interventions to improve post-stroke arm function. However, similar investigations of the legs have lagged behind, in part, due to the anatomical difficulty in using TMS to stimulate the leg motor cortical areas. Additionally, leg movements are predominately bilaterally controlled and require interlimb coordination that may involve both hemispheres. The sensitive, but invasive, tools used in animal models of locomotion hold great potential for increasing our understanding of the bihemispheric motor cortical control of walking. In this review, we discuss 3 themes associated with the bihemispheric motor cortical control of walking after stroke: (a) what is known about the role of the bihemispheric motor cortical control in healthy and poststroke leg movements, (b) how the neural remodeling of the contralesional hemisphere can affect walking recovery after a stroke, and (c) what is the effect of behavioral rehabilitation training of walking on the neural remodeling of the motor cortical areas bilaterally. For each theme, we discuss how rodent models can enhance the present knowledge on human walking by testing hypotheses that cannot be investigated in humans, and how these findings can then be back-translated into the neurorehabilitation of poststroke walking.

  6. Towards dynamic control of wettability by using functionalized altitudinal molecular motors on solid surfaces.

    Science.gov (United States)

    London, Gábor; Chen, Kuang-Yen; Carroll, Gregory T; Feringa, Ben L

    2013-08-05

    We report the synthesis of altitudinal molecular motors that contain functional groups in their rotor part. In an approach to achieve dynamic control over the properties of solid surfaces, a hydrophobic perfluorobutyl chain and a relatively hydrophilic cyano group were introduced to the rotor part of the motors. Molecular motors were attached to quartz surfaces by using interfacial 1,3-dipolar cycloadditions. To test the effect of the functional groups on the rotary motion, photochemical and thermal isomerization studies of the motors were performed both in solution and when attached to the surface. We found that the substituents have no significant effect on the thermal and photochemical processes, and the functionalized motors preserved their rotary function both in solution and on a quartz surface. Preliminary results on the influence of the functional groups on surface wettability are also described.

  7. 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.

  8. Reduction of current chopping noise with DSP controller in switched reluctance motor drive system

    Institute of Scientific and Technical Information of China (English)

    郭伟; 詹琼华; 马志源

    2002-01-01

    A novel current chopping mode was used in a switched reluctance motor drive system to make full use of the characteristics of digital signal processor (DSP) TMS320F240. The necessity of this 180° phase-shift current control (PSCC) mode is introduced first and then the principle of PSCC covering both hardware requirement and software programming is described in detail. The analysis made indicated that with this mode, the chopping frequency in winding can reach 20 kHz with 10 kHz power switches and the control frequency can reach 40 kHz at the same time. Subsequently, based on the linear and nonlinear mathematical models of the switched reluctance motor ( SRM), some simulation work has been done. The simulation results show that when this mode is applied to SRM drive (SRD) system, the current waveform becomes better. So the ripple of the torque is reduced simultaneously and the vibration and acoustic noise are reduced involuntarily. Stationary tests show that the acoustic noise is greatly diminished. Finally, some experiments were made using a 50 kW SRD system for electric vehicle (EV). Experimental results indicate that this mode can be implemented feasibly and it has a good action on the SRD system.

  9. Neurotechnology for monitoring and restoring sensory, motor, and autonomic functions

    Science.gov (United States)

    Wu, Pae C.; Knaack, Gretchen; Weber, Douglas J.

    2016-05-01

    The rapid and exponential advances in micro- and nanotechnologies over the last decade have enabled devices that communicate directly with the nervous system to measure and influence neural activity. Many of the earliest implementations focused on restoration of sensory and motor function, but as knowledge of physiology advances and technology continues to improve in accuracy, precision, and safety, new modes of engaging with the autonomic system herald an era of health restoration that may augment or replace many conventional pharmacotherapies. DARPA's Biological Technologies Office is continuing to advance neurotechnology by investing in neural interface technologies that are effective, reliable, and safe for long-term use in humans. DARPA's Hand Proprioception and Touch Interfaces (HAPTIX) program is creating a fully implantable system that interfaces with peripheral nerves in amputees to enable natural control and sensation for prosthetic limbs. Beyond standard electrode implementations, the Electrical Prescriptions (ElectRx) program is investing in innovative approaches to minimally or non-invasively interface with the peripheral nervous system using novel magnetic, optogenetic, and ultrasound-based technologies. These new mechanisms of interrogating and stimulating the peripheral nervous system are driving towards unparalleled spatiotemporal resolution, specificity and targeting, and noninvasiveness to enable chronic, human-use applications in closed-loop neuromodulation for the treatment of disease.

  10. PARAMETER ESTIMATION OF VSI FED PERMANENT MAGNET SYNCHRONOUS MOTOR BY USING HARTLEY MODULATING FUNCTION

    Directory of Open Access Journals (Sweden)

    P. Ramana

    2011-08-01

    Full Text Available This paper discusses modeling and parameter estimation of PMSM. The design of a control system for a high performance drive requires a mathematical model of the motor. This is usually derived fromphysical principles, then the parameters of the motor are determined through off-line testing or estimated on-line from input/output operating records data. The dynamics of synchronous motor can be described by a set of differential equations relating voltages, currents, speed and torque. The equations represented in d-q axes variables in the rotor reference frame using park’s transformation are presented. A parameter estimation technique employing the Hartley modulating function (HMF is detailed. Using the data obtained from open loop simulation physical parameters such as stator resistance andinductances as well as mechanical parameters such as moment of inertia and viscous friction coefficient have been estimated with a fair amount of accuracy. This estimate has been found to be quite sensitive to the choice of sampling period.

  11. Assessment of motor function, sensory motor gating and recognition memory in a novel BACHD transgenic rat model for huntington disease.

    Directory of Open Access Journals (Sweden)

    Yah-Se K Abada

    Full Text Available RATIONALE: Huntington disease (HD is frequently first diagnosed by the appearance of motor symptoms; the diagnosis is subsequently confirmed by the presence of expanded CAG repeats (> 35 in the HUNTINGTIN (HTT gene. A BACHD rat model for HD carrying the human full length mutated HTT with 97 CAG-CAA repeats has been established recently. Behavioral phenotyping of BACHD rats will help to determine the validity of this model and its potential use in preclinical drug discovery studies. OBJECTIVES: The present study seeks to characterize the progressive emergence of motor, sensorimotor and cognitive deficits in BACHD rats. MATERIALS AND METHODS: Wild type and transgenic rats were tested from 1 till 12 months of age. Motor tests were selected to measure spontaneous locomotor activity (open field and gait coordination. Sensorimotor gating was assessed in acoustic startle response paradigms and recognition memory was evaluated in an object recognition test. RESULTS: Transgenic rats showed hyperactivity at 1 month and hypoactivity starting at 4 months of age. Motor coordination imbalance in a Rotarod test was present at 2 months and gait abnormalities were seen in a Catwalk test at 12 months. Subtle sensorimotor changes were observed, whereas object recognition was unimpaired in BACHD rats up to 12 months of age. CONCLUSION: The current BACHD rat model recapitulates certain symptoms from HD patients, especially the marked motor deficits. A subtle neuropsychological phenotype was found and further studies are needed to fully address the sensorimotor phenotype and the potential use of BACHD rats for drug discovery purposes.

  12. Predicting the performance of motor imagery in stroke patients: multivariate pattern analysis of functional MRI data.

    Science.gov (United States)

    Park, Chang-hyun; Chang, Won Hyuk; Lee, Minji; Kwon, Gyu Hyun; Kim, Laehyun; Kim, Sung Tae; Kim, Yun-Hee

    2015-01-01

    In a brain-computer interface for stroke rehabilitation, motor imagery is a preferred means for providing a gateway to an effector action or behavior. However, stroke patients often exhibit failure to comply with motor imagery, and therefore their motor imagery performance is highly variable. We sought to identify motor cortical areas responsible for motor imagery performance in stroke patients, specifically by using a multivariate pattern analysis of functional magnetic resonance imaging data. We adopted an imaginary finger tapping task in which motor imagery performance could be monitored for 12 chronic stroke patients with subcortical infarcts and 12 age- and sex-matched healthy controls. We identified the typical activation pattern elicited for motor imagery in healthy controls, as computed over the voxels within each searchlight in the motor cortex. Then we measured the similarity of each individual's activation pattern to the typical activation pattern. In terms of activation levels, the stroke patients showed no activation in the ipsilesional primary motor cortex (M1); in terms of activation patterns, they showed lower similarity to the typical activation pattern in the area than the healthy controls. Furthermore, the stroke patients were better able to perform motor imagery if their activation patterns in the bilateral supplementary motor areas and ipsilesional M1 were close to the typical activation pattern. These findings suggest functional roles of the motor cortical areas for compliance with motor imagery in stroke, which can be applied to the implementation of motor imagery-based brain-computer interface for stroke rehabilitation. © The Author(s) 2014.

  13. 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…

  14. Supplementary motor area deactivation impacts the recovery of hand function from severe peripheral nerve injury

    Institute of Scientific and Technical Information of China (English)

    Ye-chen Lu; Han-qiu Liu; Xu-yun Hua; Yun-dong Shen; Wen-dong Xu; Jian-guang Xu; Yu-dong Gu

    2016-01-01

    Although some patients have successful peripheral nerve regeneration, a poor recovery of hand function often occurs after peripheral nerve injury. It is believed that the capability of brain plasticity is crucial for the recovery of hand function. The supplementary motor area may play a key role in brain remodeling after peripheral nerve injury. In this study, we explored the activation mode of the supplementary motor area during a motor imagery task. We investigated the plasticity of the central nervous system after brachial plexus injury, using the motor imagery task. Results from functional magnetic resonance imaging showed that after brachial plexus injury, the motor imagery task for the affected limbs of the patients triggered no obvious activation of bilateral supplementary motor areas. This result indicates that it is dififcult to excite the supplementary motor areas of brachial plexus injury patients during a motor imagery task, thereby impacting brain remodeling. Deactivation of the supplementary motor area is likely to be a serious problem for brachial plexus injury patients in terms of preparing, initiating and executing certain movements, which may be partly responsible for the unsatisfactory clinical recovery of hand function.

  15. Prenatal smoking exposure, measured as maternal serum cotinine, and children's motor developmental milestones and motor function

    DEFF Research Database (Denmark)

    Christensen, Line Høgenhof; Høyer, Birgit Bjerre; Pedersen, Henning Sloth

    2016-01-01

    BACKGROUND: Cohort studies have indicated an association between prenatal smoking exposure and children's motor difficulties. However, results are inconsistent and exposure is most often self-reported. Studies indicate that measurement of serum cotinine can result in a more accurate status...... of smoking exposure in comparison with self-report. OBJECTIVES: To investigate whether prenatal smoking exposure, measured as maternal serum cotinine, is associated with maternal interview based assessment of motor development in infancy (age at crawling, standing-up and walking) and motor skills at young...... school age (assessed by the Developmental Coordination Disorder Questionnaire 2007 (DCDQ'07)). METHOD: In 2002-2004, 1,253 pregnant women from Greenland and Ukraine were included in the INUENDO birth cohort. The participating women filled in questionnaires and 1,177 provided blood samples, which were...

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

    Directory of Open Access Journals (Sweden)

    Carolina Lundberg Luz

    Full Text Available ABSTRACT 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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.

  19. The effect of subclinical infantile thiamine deficiency on motor function in preschool children.

    Science.gov (United States)

    Harel, Yael; Zuk, Luba; Guindy, Michal; Nakar, Orly; Lotan, Dafna; Fattal-Valevski, Aviva

    2017-01-29

    We investigated the long-term implications of infantile thiamine (vitamin B1) deficiency on motor function in preschoolers who had been fed during the first 2 years of life with a faulty milk substitute. In this retrospective cohort study, 39 children aged 5-6 years who had been exposed to a thiamine-deficient formula during infancy were compared with 30 age-matched healthy children with unremarkable infant nutritional history. The motor function of the participants was evaluated with The Movement Assessment Battery for Children (M-ABC) and the Zuk Assessment. Both evaluation tools revealed statistically significant differences between the exposed and unexposed groups for gross and fine motor development (p motor development (p = .004). The differences were especially noteworthy on M-ABC testing for balance control functioning (p motor skills (p children exhibiting motor function difficulties in comparison to unexposed group (M-ABC: 56% vs. 10%, Zuk Assessment: 59% vs. 3%, p motor function and balance skills in childhood, thiamine having a crucial role in normal motor development. The study emphasizes the importance of proper infant feeding and regulatory control of breast milk substitutes.

  20. Discriminating hand gesture motor imagery tasks using cortical current density estimation.

    Science.gov (United States)

    Edelman, Bradley; Baxter, Bryan; He, Bin

    2014-01-01

    Current EEG based brain computer interface (BCI) systems have achieved successful control in up to 3 dimensions; however the current paradigm may be unnatural for many rehabilitative and recreational applications. Therefore there is a great need to find motor imagination (MI) tasks that are realistic for output device control. In this paper we present our results on classifying hand gesture MI tasks, including right hand flexion, extension, supination and pronation using a novel EEG inverse imaging approach. By using both temporal and spatial specificity in the source domain we were able to separate MI tasks with up to 95% accuracy for binary classification of any two tasks compared to a maximum of only 79% in the sensor domain.

  1. Single-current-sensor-based active front-end-converter-fed four quadrants induction motor drive

    Indian Academy of Sciences (India)

    JOSEPH KIRAN BANDA; AMIT KUMAR JAIN

    2017-08-01

    Induction motor (IM) is a workhorse of the industry, whose dynamics can be modified close to that of a separately excited DC machine by field-oriented control technique, which is commonly known as vector control of induction machine. This paper presents a complete performance of the field-oriented control of IM drive in all four quadrants with a single-current-sensor-based active front end converter whose work is to regulate DC link voltage, draw pure sinusoidal currents at unity power factor and to facilitate bi-directional power flow between the grid and the drive. The entire system is completely modelled in MATLAB/SIMULINK and the results are discussed in detail. The vector control analogy of the back to back converters is highlighted along with the experimental results of field-oriented control of induction machine using a dsPIC30F6010A digital signal controller.

  2. Transcranial Direct Current Stimulation Potentiates Improvements in Functional Ability in Patients With Chronic Stroke Receiving Constraint-Induced Movement Therapy

    DEFF Research Database (Denmark)

    Figlewski, Krystian; Blicher, Jakob Udby; Mortensen, Jesper;

    2017-01-01

    BACKGROUND AND PURPOSE: Transcranial direct current stimulation may enhance effect of rehabilitation in patients with chronic stroke. The objective was to evaluate the efficacy of anodal transcranial direct current stimulation combined with constraint-induced movement therapy of the paretic upper...... limb. METHODS: A total of 44 patients with stroke were randomly allocated to receive 2 weeks of constraint-induced movement therapy with either anodal or sham transcranial direct current stimulation. The primary outcome measure, Wolf Motor Function Test, was assessed at baseline and after...... the intervention by blinded investigators. RESULTS: Both groups improved significantly on all Wolf Motor Function Test scores. Group comparison showed improvement on Wolf Motor Function Test in the anodal group compared with the sham group. CONCLUSIONS: Anodal transcranial direct current stimulation combined...

  3. Somatotopic mapping of the human primary sensorimotor cortex during motor imagery and motor execution by functional magnetic resonance imaging.

    Science.gov (United States)

    Stippich, Christoph; Ochmann, Henrik; Sartor, Klaus

    2002-10-04

    The human primary sensorimotor cortex was investigated for somatotopic organization during motor imagery (IM) which was compared to motor execution (EM). Block designed BOLD (blood oxygen level dependent)-functional magnetic resonance imaging at 1.5 Tesla was applied in 14 right handed volunteers during imagined and executed tongue, finger and toe movements. BOLD-clusters were assessed for anatomically correct sensorimotor localization. Euklidian coordinates, relative signal change and correlation to the applied reference function were determined. Statistical means were calculated. IM recruited somatotopically organized primary sensorimotor representations of the precentral gyrus that reflected the homunculus and overlapped in part with EM representations. Mean BOLD-signals ranged from 1.93 to 3.18% for EM, and from 0.73 to 1.47% for IM. The results support the hypothesis that the primary sensorimotor cortex is active during IM and that IM and EM share common functional circuits.

  4. The gross motor function measure is a valid and sensitive outcome measure for spinal muscular atrophy.

    Science.gov (United States)

    Nelson, Leslie; Owens, Hollis; Hynan, Linda S; Iannaccone, Susan T

    2006-06-01

    Spinal muscular atrophy is a genetic disease of the anterior horn cell with high morbidity rate in childhood. Certain drugs may be of benefit and are in or under consideration for Phase II trials. Outcome measures that are age appropriate and representative of disease activity remain under study. Several have not yet been validated for spinal muscular atrophy. The Gross Motor Function Measure is a measure of motor function. We showed previously that the Gross Motor Function Measure is a reliable outcome measure to assess motor function in children with spinal muscular atrophy. By collating our data from 40 spinal muscular atrophy patients, ages 5 through 17 years, we now show the validity of the Gross Motor Function Measure when compared to Quantitative Muscle Testing and ambulatory status in children with spinal muscular atrophy. The median for Gross Motor Function Measure total scores for walkers was 237 (range: 197-261) and for non-walkers, 64 (range: 4-177; PGross Motor Function Measure is valid and sensitive as an outcome measure for clinical trials in pediatric spinal muscular atrophy.

  5. Functional Magnetic Resonance Imaging Neurofeedback-guided Motor Imagery Training and Motor Training for Parkinson’s Disease: Randomized Trial

    Science.gov (United States)

    Subramanian, Leena; Morris, Monica Busse; Brosnan, Meadhbh; Turner, Duncan L.; Morris, Huw R.; Linden, David E. J.

    2016-01-01

    Objective: Real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback (NF) uses feedback of the patient’s own brain activity to self-regulate brain networks which in turn could lead to a change in behavior and clinical symptoms. The objective was to determine the effect of NF and motor training (MOT) alone on motor and non-motor functions in Parkinson’s Disease (PD) in a 10-week small Phase I randomized controlled trial. Methods: Thirty patients with Parkinson’s disease (PD; Hoehn and Yahr I-III) and no significant comorbidity took part in the trial with random allocation to two groups. Group 1 (NF: 15 patients) received rt-fMRI-NF with MOT. Group 2 (MOT: 15 patients) received MOT alone. The primary outcome measure was the Movement Disorder Society—Unified PD Rating Scale-Motor scale (MDS-UPDRS-MS), administered pre- and post-intervention “off-medication”. The secondary outcome measures were the “on-medication” MDS-UPDRS, the PD Questionnaire-39, and quantitative motor assessments after 4 and 10 weeks. Results: Patients in the NF group were able to upregulate activity in the supplementary motor area (SMA) by using motor imagery. They improved by an average of 4.5 points on the MDS-UPDRS-MS in the “off-medication” state (95% confidence interval: −2.5 to −6.6), whereas the MOT group improved only by 1.9 points (95% confidence interval +3.2 to −6.8). The improvement in the intervention group meets the minimal clinically important difference which is also on par with other non-invasive therapies such as repetitive Transcranial Magnetic Stimulation (rTMS). However, the improvement did not differ significantly between the groups. No adverse events were reported in either group. Interpretation: This Phase I study suggests that NF combined with MOT is safe and improves motor symptoms immediately after treatment, but larger trials are needed to explore its superiority over active control conditions. PMID:27375451

  6. Predictive current control of permanent magnet synchronous motor based on linear active disturbance rejection control

    Science.gov (United States)

    Li, Kunpeng

    2017-01-01

    The compatibility problem between rapidity and overshooting in the traditional predictive current control structure is inevitable and difficult to solve by reason of using PI controller. A novel predictive current control (PCC) algorithm for permanent magnet synchronous motor (PMSM) based on linear active disturbance rejection control (LADRC) is presented in this paper. In order to displace PI controller, the LADRC strategy which consisted of linear state error feedback (LSEF) control algorithm and linear extended state observer (LESO), is designed based on the mathematic model of PMSM. The purpose of LSEF is to make sure fast response to load mutation and system uncertainties, and LESO is designed to estimate the uncertain disturbances. The principal structures of the proposed system are speed outer loop based on LADRC and current inner loop based on predictive current control. Especially, the instruction value of qaxis current in inner loop is derived from the control quantity which is designed in speed outer loop. The simulation is carried out in Matlab/Simulink software, and the results illustrate that the dynamic and static performances of proposed system are satisfied. Moreover the robust against model parameters mismatch is enhanced obviously.

  7. Mapping the motor and sensory cortices: a historical look and a current case study in sensorimotor localization and direct cortical motor stimulation.

    Science.gov (United States)

    Silverstein, Justin

    2012-03-01

    The utilization of cortical mapping during craniotomies for epilepsy and brain tumor resection is extremely important. Cortical mapping can guide the surgical team intraoperatively with regards to the layout of important anatomical structures and their function to prevent post-operative deficits. Electroneurophysiological methods employed include sensorimotor localization recorded directly from the surface of the brain when stimulated from a peripheral nerve and direct cortical stimulation (DCS) of the motor cortex to elicit a distal muscle response. This paper presents a case, in which a paradigm of neurophysiological modalities is utilized to assist the surgeon in creating a topographic map of the motor cortex and with localizing the sensory and motor cortices, in addition to a historical review of functional localization.

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

    Directory of Open Access Journals (Sweden)

    Charlotte Rosso

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

  9. 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…

  10. 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…

  11. 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

  12. Stimulation through Simulation? Motor Imagery and Functional Reorganization in Hemiplegic Stroke Patients

    Science.gov (United States)

    Johnson-Frey, Scott H.

    2004-01-01

    A key factor influencing reorganization of function in damaged neural networks of the adult brain is stimulation. How to stimulate motor areas of patients with paralyses is a formidable challenge. One possibility is to use internal movement simulations, or motor imagery, as an alternative to conventional therapeutic interventions that require…

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

    NARCIS (Netherlands)

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

  14. 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…

  15. Association between motor and mental functioning in toddlers with cerebral palsy

    NARCIS (Netherlands)

    Enkelaar, Lotte; Ketelaar, Marjolijn; Gorter, Jan Willem

    2008-01-01

    Purpose: This study aimed to examine the association between motor and mental functioning in toddlers with cerebral palsy (CP). Methods: The Mental and Motor Scales of the Bayley Scales of Infant Development-Second Edition (BSID-II) were administered. Subjects: Seventy-eight toddlers with CP (mean a

  16. Establishing score equivalence of the Functional Independence Measure motor scale and the Barthel Index, utilising the International Classification of Functioning, Disability and Health and Rasch measurement theory.

    Science.gov (United States)

    Prodinger, Birgit; O'Connor, Rory J; Stucki, Gerold; Tennant, Alan

    2017-05-16

    Two widely used outcome measures to assess functioning in neurological rehabilitation are the Functional Independence Measure (FIM™) and the Barthel Index. The current study aims to establish the equivalence of the total score of the FIM™ motor scale and the Barthel Index through the application of the International Classification of Functioning, Disability and Health, and Rasch measurement theory. Secondary analysis of a large sample of patients with stroke, spinal cord injury, and multiple sclerosis, undergoing rehabilitation was conducted. All patients were assessed at the same time on both the FIM™ and the Barthel Index. The International Classification of Functioning, Disability and Health Linking Rules were used to establish conceptual coherency between the 2 scales, and the Rasch measurement model to establish an exchange of the total scores. Using the FIM™ motor scale, items from both scales linked to the International Classification of Functioning, Disability and Health d4 Mobility or d5 Self-care chapters. Their co-calibration satisfied the assumptions of the Rasch model for each of 3 diagnostic groups. A ceiling effect was observed for the Barthel Index when contrasted against the FIM™ motor scale. Having a Rasch interval metric to transform scores between the FIM™ motor scale and Barthel Index is valuable for monitoring functioning, meta-analysis, quality audits and hospital benchmarking.

  17. 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...

  18. Complexity of motor sequences and cortical reorganization in Parkinson's disease: a functional MRI study.

    Directory of Open Access Journals (Sweden)

    Stefano Caproni

    Full Text Available Motor impairment is the most relevant clinical feature in Parkinson's disease (PD. Functional imaging studies on motor impairment in PD have revealed changes in the cortical motor circuits, with particular involvement of the fronto-striatal network. The aim of this study was to assess brain activations during the performance of three different motor exercises, characterized by progressive complexity, using a functional fMRI multiple block paradigm, in PD patients and matched control subjects. Unlike from single-task comparisons, multi-task comparisons between similar exercises allowed to analyse brain areas involved in motor complexity planning and execution. Our results showed that in the single-task comparisons the involvement of primary and secondary motor areas was observed, consistent with previous findings based on similar paradigms. Most notably, in the multi-task comparisons a greater activation of supplementary motor area and posterior parietal cortex in PD patients, compared with controls, was observed. Furthermore, PD patients, compared with controls, had a lower activation of the basal ganglia and limbic structures, presumably leading to the impairment in the higher levels of motor control, including complexity planning and execution. The findings suggest that in PD patients occur both compensatory mechanisms and loss of efficiency and provide further insight into the pathophysiological role of distinct cortical and subcortical areas in motor dysfunction.

  19. Complexity of motor sequences and cortical reorganization in Parkinson's disease: a functional MRI study.

    Science.gov (United States)

    Caproni, Stefano; Muti, Marco; Principi, Massimo; Ottaviano, Pierfausto; Frondizi, Domenico; Capocchi, Giuseppe; Floridi, Piero; Rossi, Aroldo; Calabresi, Paolo; Tambasco, Nicola

    2013-01-01

    Motor impairment is the most relevant clinical feature in Parkinson's disease (PD). Functional imaging studies on motor impairment in PD have revealed changes in the cortical motor circuits, with particular involvement of the fronto-striatal network. The aim of this study was to assess brain activations during the performance of three different motor exercises, characterized by progressive complexity, using a functional fMRI multiple block paradigm, in PD patients and matched control subjects. Unlike from single-task comparisons, multi-task comparisons between similar exercises allowed to analyse brain areas involved in motor complexity planning and execution. Our results showed that in the single-task comparisons the involvement of primary and secondary motor areas was observed, consistent with previous findings based on similar paradigms. Most notably, in the multi-task comparisons a greater activation of supplementary motor area and posterior parietal cortex in PD patients, compared with controls, was observed. Furthermore, PD patients, compared with controls, had a lower activation of the basal ganglia and limbic structures, presumably leading to the impairment in the higher levels of motor control, including complexity planning and execution. The findings suggest that in PD patients occur both compensatory mechanisms and loss of efficiency and provide further insight into the pathophysiological role of distinct cortical and subcortical areas in motor dysfunction.

  20. Prediction of motor and functional outcomes in infants born preterm assessed at term.

    Science.gov (United States)

    Snider, Laurie; Majnemer, Annette; Mazer, Barbara; Campbell, Suzann; Bos, Arend F

    2009-01-01

    To compare 3 different assessment approaches at term to infants born preterm to predict motor and functional outcomes at 12 months adjusted age. Infants (n = 100) born at less than 32 weeks postconceptional age were assessed at term using the General Movements Assessment, Einstein Neonatal Neurobehavioral Assessment Scales, Test of Infant Motor Performance, and at 12 months adjusted age using the Alberta Infant Motor Scales, Peabody Developmental Motor Scales-2, Vineland Adaptive Behavior Scales-Daily Living Skills, and Battelle Developmental Inventory. The General Movements Assessment (r2 = 0.04; p = 0.05) and the Test of Infant Motor Performance (r2 = 0.05; p = 0.04) predicted outcomes on the Peabody Developmental Motor Scales-2. The Test of Infant Motor Performance predicted outcomes on the Alberta Infant Motor Scales (r2 = 0.05; p = 0.04) and Vineland Adaptive Behavior Scales-Daily Living Skills (odds ratio: 0.93). Delays in functional performance were found. Neonatal tests at term explained a small but significant proportion of the variance in gross motor and daily living skills at 12 months adjusted age.

  1. 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 Motor Function Measure Evolution 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.

  2. Impact of tactile function on upper limb motor function in children with Developmental Coordination Disorder.

    Science.gov (United States)

    Cox, Lauren E; Harris, Elizabeth C; Auld, Megan L; Johnston, Leanne M

    2015-01-01

    This study investigated the presence of, and relationship between tactile dysfunction and upper limb motor function in children with Developmental Coordination Disorder (DCD) compared to typical developing (TD) children. Participants were 36 children aged 6-12 years. Presence of DCD (n=20) or TD (n=16) was confirmed using the Movement Assessment Battery for Children, second edition. All children participated in a comprehensive assessment of tactile registration (Semmes Weinstein Monofilaments); tactile spatial perception (Single Point Localisation (SPL) and two-point discrimination (2PD)); haptic perception (Stereognosis); speed of simple everyday manual tasks (Jebsen-Taylor Test of Hand Function (JTTHF)); and handwriting speed and accuracy (Evaluation Tool of Children's Handwriting (ETCH)). Compared to TD children, children with DCD demonstrated poorer localisation of touch in the non-dominant hand (p=0.04), slower speed of alphabet writing (p0.05). Regression analysis showed that spatial tactile perception (SPL) predicted handwriting legibility (ETCH: r=0.11) and speed of functional tasks (JTTHF: r=0.33). These results suggest that tactile function, specifically single point localisation, should be a primary tactile assessment employed to determine reasons for upper limb motor difficulties experienced by children with DCD.

  3. Combined motor point associative stimulation (MPAS) and transcranial direct current stimulation (tDCS) improves plateaued manual dexterity performance.

    Science.gov (United States)

    Hoseini, Najmeh; Munoz-Rubke, Felipe; Wan, Hsuan-Yu; Block, Hannah J

    2016-10-28

    Motor point associative stimulation (MPAS) in hand muscles is known to modify motor cortex excitability and improve learning rate, but not plateau of performance, in manual dexterity tasks. Central stimulation of motor cortex, such as transcranial direct current stimulation (tDCS), can have similar effects if accompanied by motor practice, which can be difficult and tiring for patients. Here we asked whether adding tDCS to MPAS could improve manual dexterity in healthy individuals who are already performing at their plateau, with no motor practice during stimulation. We hypothesized that MPAS could provide enough coordinated muscle activity to make motor practice unnecessary, and that this combination of stimulation techniques could yield improvements even in subjects at or near their peak. If so, this approach could have a substantial effect on patients with impaired dexterity, who are far from their peak. MPAS was applied for 30min to two right hand muscles important for manual dexterity. tDCS was simultaneously applied over left sensorimotor cortex. The motor cortex input/output (I/O) curve was assessed with transcranial magnetic stimulation (TMS), and manual dexterity was assessed with the Purdue Pegboard Test. Compared to sham or cathodal tDCS combined with MPAS, anodal tDCS combined with MPAS significantly increased the plateau of manual dexterity. This result suggests that MPAS has the potential to substitute for motor practice in mediating a beneficial effect of tDCS on manual dexterity.

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

    Science.gov (United States)

    Ramsey, NF; Aarnoutse, EJ; Vansteensel, MJ

    2017-01-01

    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 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 (BCI). Although some non-invasive applications produce good results, we focus on brain implants which 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. PMID:24642607

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

    Science.gov (United States)

    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.

  6. Functional mapping of the sensorimotor cortex: combined use of magnetoencephalography, functional MRI, and motor evoked potentials

    Energy Technology Data Exchange (ETDEWEB)

    Morioka, T. [Dept. of Neurosurgery, Neurological Inst., Kyshu Univ., Fukuoka (Japan); Fujii, K. [Dept. of Neurosurgery, Neurological Inst., Kyshu Univ., Fukuoka (Japan); Fukui, M. [Dept. of Neurosurgery, Neurological Inst., Kyshu Univ., Fukuoka (Japan); Mizushima, A. [Dept. of Radiology, Kyushu Univ. Fukuoka (Japan); Matsumoto, S. [Dept. of Radiology, Kyushu Univ. Fukuoka (Japan); Hasuo, K. [Dept. of Radiology, Kyushu Univ. Fukuoka (Japan); Yamamoto, T. [Dept. of Otolaryngology, Kyushu Univ. Fukuoka (Japan); Tobimatsu, S. [Dept. of Clinical Neurophysiology, Neurological Inst., Kyushu Univ., Fukuoka (Japan)

    1995-10-01

    Combined use of magnetoencephalography (MEG), functional magnetic resonance imaging (f-MRI), and motor evoked potentials (MEPs) was carried out on one patient in an attempt to localise precisely a structural lesion to the central sulcus. A small cyst in the right frontoparietal region was thought to be the cause of generalised seizures in an otherwise asymptomatic woman. First the primary sensory cortex was identified with magnetic source imaging (MSI) of somatosensory evoked magnetic fields using MEG and MRI. Second, the motor area of the hand was identified using f-MRI during handsqueezing. Then transcranial magnetic stimulation localised the hand motor area on the scalp, which was mapped onto the MRI. There was a good agreement between MSI, f-MRI and MEP as to the location of the sensorimotor cortex and its relationship to the lesion. Multimodality mapping techniques may thus prove useful in the precise localisation of cortical lesions, and in the preoperative determination of the best treatment for peri-rolandic lesions. (orig.)

  7. 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.

  8. Generation of complex motor patterns in american grasshopper via current-controlled thoracic electrical interfacing.

    Science.gov (United States)

    Giampalmo, Susan L; Absher, Benjamin F; Bourne, W Tucker; Steves, Lida E; Vodenski, Vassil V; O'Donnell, Peter M; Erickson, Jonathan C

    2011-01-01

    Micro-air vehicles (MAVs) have attracted attention for their potential application to military applications, environmental sensing, and search and rescue missions. While progress is being made toward fabrication of a completely human-engineered MAV, another promising approach seeks to interface to, and take control of, an insect's nervous system. Cyborg insects take advantage of their innate exquisite loco-motor, navigation, and sensing abilities. Recently, several groups have demonstrated the feasibility of radio-controlled flight in the hawkmoth and beetle via electrical neural interfaces. Here, we report a method for eliciting the "jump" response in the American grasshopper (S. Americana). We found that stimulating the metathoracic T3 ganglion with constant-current square wave pulses with amplitude 186 ± 40 μA and frequency 190 ± 13 Hz reproducibly evoked (≥95% success rate) the desired motor activity in N=3 test subjects. To the best of our knowledge, this is the first report of an insect cyborg with a synchronous neuromuscular system.

  9. Motor Sequence Learning in Healthy Older Adults Is Not Necessarily Facilitated by Transcranial Direct Current Stimulation (tDCS)

    OpenAIRE

    Raw, RK; Allen, RJ; Mon-Williams, M; Wilkie, RM

    2016-01-01

    Background: Transcranial Direct Current Stimulation (tDCS) of the primary motor cortex (M1) can modulate neuronal activity, and improve performance of basic motor tasks. The possibility that tDCS could assist in rehabilitation (e.g., for paresis post-stroke) offers hope but the evidence base is incomplete, with some behavioural studies reporting no effect of tDCS on complex motor learning. Older adults who show age-related decline in movement and learning (skills which tDCS could potentially ...

  10. The effects of cervical transcutaneous spinal direct current stimulation on motor pathways supplying the upper limb in humans.

    Science.gov (United States)

    Dongés, Siobhan C; D'Amico, Jessica M; Butler, Jane E; Taylor, Janet L

    2017-01-01

    Non-invasive, weak direct current stimulation can induce changes in excitability of underlying neural tissue. Many studies have used transcranial direct current stimulation to induce changes in the brain, however more recently a number of studies have used transcutaneous spinal direct current stimulation to induce changes in the spinal cord. This study further characterises the effects following cervical transcutaneous spinal direct current stimulation on motor pathways supplying the upper limb. In Study 1, on two separate days, participants (n = 12, 5 F) received 20 minutes of either real or sham direct current stimulation at 3 mA through electrodes placed in an anterior-posterior configuration over the neck (anode anterior). Biceps brachii, flexor carpi radialis and first dorsal interosseous responses to transcranial magnetic stimulation (motor evoked potentials) and cervicomedullary stimulation (cervicomedullary motor evoked potentials) were measured before and after real or sham stimulation. In Study 2, on two separate days, participants (n = 12, 7 F) received either real or sham direct current stimulation in the same way as for Study 1. Before and after real or sham stimulation, median nerve stimulation elicited M waves and H reflexes in the flexor carpi radialis. H-reflex recruitment curves and homosynaptic depression of the H reflex were assessed. Results show that the effects of real and sham direct current stimulation did not differ for motor evoked potentials or cervicomedullary motor evoked potentials for any muscle, nor for H-reflex recruitment curve parameters or homosynaptic depression. Cervical transcutaneous spinal direct current stimulation with the parameters described here does not modify motor responses to corticospinal stimulation nor does it modify H reflexes of the upper limb. These results are important for the emerging field of transcutaneous spinal direct current stimulation.

  11. Four types of potassium currents in motor nerve terminals of snake

    Institute of Scientific and Technical Information of China (English)

    施玉樑; 顾琛; 徐幼芬

    1997-01-01

    The experiments were perfomed on transvcrsus abdominis muscle of Elaphe dione by subendothelial recording. The results indicate that in snake motor nerve endings there exist four types of K* channels, i.e. voltage-dependent fast and slow K+ channels, Ca2 +-activated K+ channel and ATP-sensitive K+ channel, (i) The typical wave form of snake terminal current was the double-peaked negativity in standard solution. The first peak was at-tributed to Na influx (INa) in nodes of Ranvier. The second one was blocked by 3, 4-aminopyridine (3, 4-DAP) or te-traethylammonium (TEA), which corresponded to fast K+ outward current (IKF) through the fast K* channels in terminal part, (ii) After IKF as well as the slow K+ current (IKS) were blocked by 3, 4-DAP, the TEA-sensitive Ca2+-dependent K+ current (IK(Ca)) passing through Ca2+-activated K+ channel was revealed, whose amplitude depended on [K+ ]and [Ca2+ ] It was blocked by Ba2+ , Cd2+ or Co2+ . (iii) IK.F and IK(Ca) were blocked by TEA, while IK.S was retained. It

  12. 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

    2016-06-01

    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.

  13. 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.

  14. Speed Control of Brushless Dc Motor Using Current Fed Quasi Z-source Inverter with Regeneration Capability

    Directory of Open Access Journals (Sweden)

    A. Santhi Mary Antony

    2015-06-01

    Full Text Available Current fed Quasi Z-Source Inverters (qZSI have the advantages of voltage buck-boost capability, improved reliability, reduced passive component ratings, continuous input current, a common dc rail between source and inverter and unique regeneration capability. This current-fed qZSIs are bidirectional with an additional diode, unlike the voltage-fed ZSI that needs a switch to achieve bidirectional power flow. Since current fed quasi Z Source Inverter has many advantages it can be employed for motor drive applications such as Brushless DC motor (BLDC drive. Therefore this study proposes the use of qZSI for BLDC motor. The simulation results for the same are presented in this study.

  15. 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

    expressed concern about the child’s motor development had a sensitivity of 17.0% and a specificity of 93.9%. 
 Conclusion: 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......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...

  16. Optimal stimulation parameters for Renzhong (DU 26) electro-acupuncture for improving motor function in a rat model of middle cerebral artery occlusion

    Institute of Scientific and Technical Information of China (English)

    Lin Han; Shu Wang; Jinquan Ma; Wenping Yao; Yan Shen; Xuemin Shi

    2011-01-01

    The selection of electro-acupuncture parameters remains poorly unified between clinical studies. The present study observed the effects of electro-acupuncturing Renzhong (DU 26) with different stimulation parameters on motor function recovery following middle artery occlusion injury in rats. Results showed an optimal stimulation parameter for Renzhong electro-acupuncture that was low frequency and mild current (2 Hz, 1 mA) significantly improved cortical excitability and conductive function, and promoted recovery in a rat model of motor function in middle artery occlusion. Frequency had a greater impact than current or interaction, and played a critical role in electro-acupuncture therapy.

  17. Inverter and Motor Model Adaptation at Stand-Still Using Reference Voltages and Measured Currents

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Tønnes, M.; Knudsen, Morten

    1995-01-01

    A model adaptation method for estimating the electrical parameters of an induction motor at stand-still is described.......A model adaptation method for estimating the electrical parameters of an induction motor at stand-still is described....

  18. Psychological consequences of congenital hypothyroidism: Cognitive, motor and psychosocial functioning

    NARCIS (Netherlands)

    van der Sluijs Veer, L.

    2013-01-01

    This thesis shows that although the development of children with (permanent) congenital hypothyroidism (CH) is considerably improved by early treatment as a result of neonatal screening, they are still at risk for motor and cognitive problems. This applies especially for children with severe CH. Fin

  19. Some Current Themes in Functional Analysis Research.

    Science.gov (United States)

    Vollmer, Timothy R.; Smith, Richard G.

    1996-01-01

    This article discusses clinical application of functional analysis in developmental disabilities, reviewing issues related to treatment logic and development. The article then approaches functional analysis as a research method, reviewing three areas of research: analysis of diverse response topographies, analysis of basic behavioral processes,…

  20. Note: Fast compact laser shutter using a direct current motor and three-dimensional printing

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Grace H., E-mail: ghzhang0@mit.edu; Braverman, Boris; Kawasaki, Akio; Vuletić, Vladan [Department of Physics, MIT-Harvard Center for Ultracold Atoms and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-12-15

    We present a mechanical laser shutter design that utilizes a direct current electric motor to rotate a blade which blocks and unblocks a light beam. The blade and the main body of the shutter are modeled with computer aided design (CAD) and are produced by 3D printing. Rubber flaps are used to limit the blade’s range of motion, reducing vibrations and preventing undesirable blade oscillations. At its nominal operating voltage, the shutter achieves a switching speed of (1.22 ± 0.02) m/s with 1 ms activation delay and 10 μs jitter in its timing performance. The shutter design is simple, easy to replicate, and highly reliable, showing no failure or degradation in performance over more than 10{sup 8} cycles.

  1. Visual-motor and executive functions in children born preterm: the Bender Visual Motor Gestalt Test revisited.

    Science.gov (United States)

    Böhm, Birgitta; Lundequist, Aiko; Smedler, Ann-Charlotte

    2010-10-01

    Visual-motor development and executive functions were investigated with the Bender Test at age 5½ years in 175 children born preterm and 125 full-term controls, within the longitudinal Stockholm Neonatal Project. Assessment also included WPPSI-R and NEPSY neuropsychological battery for ages 4-7 (Korkman, 1990). Bender protocols were scored according to Brannigan & Decker (2003), Koppitz (1963) and a complementary neuropsychological scoring system (ABC), aimed at executive functions and developed for this study. Bender results by all three scoring systems were strongly related to overall cognitive level (Performance IQ), in both groups. The preterm group displayed inferior visual-motor skills compared to controls also when controlling for IQ. The largest group differences were found on the ABC scoring, which shared unique variance with NEPSY tests of executive function. Multiple regression analyses showed that hyperactive behavior and inattention increased the risk for visual-motor deficits in children born preterm, whereas no added risk was seen among hyperactive term children. Gender differences favoring girls were strongest within the preterm group, presumably reflecting the specific vulnerability of preterm boys. The results indicate that preterm children develop a different neurobehavioral organization from children born at term, and that the Bender test with a neuropsychological scoring is a useful tool in developmental screening around school start.

  2. 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

  3. Direct-current-dependent shift of theta-burst-induced plasticity in the human motor cortex.

    Science.gov (United States)

    Hasan, Alkomiet; Hamada, Masashi; Nitsche, Michael A; Ruge, Diane; Galea, Joseph M; Wobrock, Thomas; Rothwell, John C

    2012-03-01

    Animal studies using polarising currents have shown that induction of synaptic long-term potentiation (LTP) and long-term depression (LTD) by bursts of patterned stimulation is affected by the membrane potential of the postsynaptic neurone. The aim of the present experiments was to test whether it is possible to observe similar phenomena in humans with the aim of improving present protocols of inducing synaptic plasticity for therapeutic purposes. We tested whether the LTP/LTD-like after effects of transcranial theta-burst stimulation (TBS) of human motor cortex, an analogue of patterned electrical stimulation in animals, were affected by simultaneous transcranial direct-current stimulation (tDCS), a non-invasive method of polarising cortical neurones in humans. Nine healthy volunteers were investigated in a single-blind, balanced cross-over study; continuous TBS (cTBS) was used to introduce LTD-like after effects, whereas intermittent TBS (iTBS) produced LTP-like effects. Each pattern was coupled with concurrent application of tDCS (motor thresholds and intracortical inhibitory/facilitatory networks were not altered by any of the stimulation protocols. We conclude that the after effects of TBS can be modulated by concurrent tDCS. We hypothesise that tDCS changes the membrane potential of the apical dendrites of cortical pyramidal neurones and that this changes the response to patterned synaptic input evoked by TBS. The data show that it may be possible to enhance LTP-like plasticity after TBS in the human cortex.

  4. Do currently recommended Bayley III cutoffs overestimate motor impairment in infants born <27 weeks gestation?

    OpenAIRE

    Duncan, Andrea F; Bann, Carla; Boatman, Cathy; Hintz, Susan R.; Vaucher, Yvonne E.; Vohr, Betty R.; Yolton, Kimberly; Heyne, Roy J.; ,

    2015-01-01

    Objective To determine whether a Bayley-III Motor Composite score of 85 may overestimate moderate-severe motor impairment by analyzing Bayley-III motor components and developing cut-point scores for each. Study Design Retrospective study of 1183 children born

  5. COMPARISON THE EFFECT OF SIMULTANEOUS SENSORY STIMULATION AND CURRENT OCCUPATIONAL THERAPY APPROACHES ON MOTOR DEVELOPMENT OF THE INFANTS WITH DOWN SYNDROME

    Directory of Open Access Journals (Sweden)

    Masoud KARIMLOO

    2010-11-01

    Full Text Available AbstractObjectiveNeuromuscular characteristics in Down syndrome result in generalized muscular hypotonia, developmental delays and sensory integration deficits. The aim of this study was to compare the effects of simultaneous sensory stimulations and current occupational therapy approaches on motor functions development of infants with Down syndrome.Materials & MethodsEighteen infants with Down syndrome, aged 6 -18 months, were evaluated in two groups: intervention group (simultaneous sensory stimulation and occupational therapy and control group (occupational therapy alone. They attended the program 3 times a week for 6 months and each session lasted 45 minutes. Motor functions were assessed before, during, and after intervention in the two groups, using GMFM test.ResultsMean motor function increased in both groups according to the GMFM test (P = 0.000. Comparison of the changes showed that although the mean difference of this variable was higher in the intervention group, the difference was not statistically significant (P = 0.576.Mean motor deficit reduced in both groups during the period of the study,which was statistically significant (P < 0.05. Comparison of the difference in mean motor deficit in the first and last evaluations showed that this difference was more in the intervention group but statistically insignificant (P = 0.617ConclusionEarly use of simultaneous sensory stimulations can improve the quality of motor skills in Down syndrome infants. It is suggested that it may be used as an early intervention in association with other methods in the rehabilitation of these patients. However, more studies in this regard are warranted.

  6. Longitudinal Association Between Gross Motor Capacity and Neuromusculoskeletal Function in Children and Youth With Cerebral Palsy

    NARCIS (Netherlands)

    Vos, Rimke C.; Becher, Jules G.; Voorman, Jeanine M.; Gorter, Jan Willem; van Eck, Mirjam; van Meeteren, Jetty; Smits, Dirk Wouter; Twisk, Jos W.; Dallmeijer, Annet J.

    2016-01-01

    Objective: To examine associations over longitudinal measurements between neuromusculoskeletal function and gross motor capacity in children and youth with cerebral palsy (CP). Design: A prospective cohort study. Setting: Rehabilitation departments of university medical centers and rehabilitations c

  7. Longitudinal Association Between Gross Motor Capacity and Neuromusculoskeletal Function in Children and Youth With Cerebral Palsy

    NARCIS (Netherlands)

    Vos, Rimke C.; Becher, Jules G.; Voorman, Jeanine M.; Gorter, Jan Willem; van Eck, Mirjam; van Meeteren, Jetty; Smits, Dirk Wouter; Twisk, Jos W.; Dallmeijer, Annet J.; van Schie, P. E M; Schuengel, C.; Ketelaar, M.; Lindeman, E.; Jongmans, M.; Roebroeck, M. E.; Tan, S. S.; Wiegerink, D. J H G; Reinders-Messelink, H. A.; Verheijden, J.

    2016-01-01

    Objective To examine associations over longitudinal measurements between neuromusculoskeletal function and gross motor capacity in children and youth with cerebral palsy (CP). Design A prospective cohort study. Setting Rehabilitation departments of university medical centers and rehabilitations cent

  8. 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

    Aim Improvement of gross motor function and mobility are primary goals of physical therapy in children with cerebral palsy (CP). The purpose of this study was to investigate the relationship between segmental control of the trunk and the corresponding gross motor function in children with CP....... Method This retrospective cross-sectional study was based on 92 consecutive referrals of children with CP in Gross Motor Function Classification System (GMFCS) levels I to V, 39 females, 53 males (median age 4y [range 1–14y]), and 77, 12, and 3 with spastic, dyskinetic, and ataxic CP respectively....... 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...

  9. Environmental Exposure to Manganese in Air: Associations with Tremor and Motor Function

    Science.gov (United States)

    BACKGROUND: Manganese (Mn) inhalation has been associated with neuropsychological and neurological sequelae in exposed workers. Few environmental epidemiologic studies have examined the potentialy neurotoxic effects of Mn exposure in ambient air on motor function and han...

  10. Motor function improvement with mirror therapy in stroke patients: a CAT

    Directory of Open Access Journals (Sweden)

    Raúl Aguilera Eguía

    2013-12-01

    Full Text Available Introduction Stroke comprises several conditions characterized by sudden, non-convulsive loss of neurological function. A large percentage of individuals who survive stroke will have limb motor sequelae. Aim To assess the validity and applicability of the results regarding the effectiveness of mirror therapy in patients with stroke and answer the following question: In stroke subjects, can mirror therapy improve motor function? Method We analyzed the article "Mirror therapy for improving motor function after stroke," Cochrane Systematic Review [Thieme 20121]. Results Mirror therapy may increase motor function between the second and sixth week of intervention, with a standardized mean difference (SMD of 0.61 (95% CI 0.22-1.00. Conclusion Despite methodological limitations of the primary studies included in the systematic review, we found that mirror therapy is a reasonable adjunct to standard therapy by physiotherapists.

  11. Effects of motor imagery on hand function during immobilization after flexor tendon repair

    NARCIS (Netherlands)

    Stenekes, Martin W.; Geertzen, Jan H.; Nicolai, Jean-Philippe A.; de Jong, Bauke M.; Mulder, Theo

    2009-01-01

    OBJECTIVE: To determine whether motor imagery during the immobilization period after flexor tendon injury results in a faster recovery of central mechanisms of hand function. DESIGN: Randomized controlled trial. SETTING: Tertiary referral hospital. PARTICIPANTS: Patients (N=28) after surgical flexor

  12. 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 significantly reduce PACU stay and enhance resource optimization and early rehabilitation but without enough data to allow clinical recommendations....... METHODS: A multicenter, semiblinded, noninferiority randomized controlled trial of discharge from the PACU with or without assessment of lower limb motor function after elective total hip or knee arthroplasty under spinal anesthesia was undertaken. The primary outcome was frequency of a successful fast.......70 to 1.35). Adverse events in the ward during the first 24 h occurred in 5.8% versus 7.4% with or without motor function assessment, respectively (OR, 0.77; 95% CI, 0.5 to 1.19, P = 0.24). CONCLUSIONS: PACU discharge without assessment of lower limb motor function after spinal anesthesia for total hip...

  13. 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.

  14. Longitudinal Association Between Gross Motor Capacity and Neuromusculoskeletal Function in Children and Youth With Cerebral Palsy

    NARCIS (Netherlands)

    Vos, Rimke C.; Becher, Jules G.; Voorman, Jeanine M.; Gorter, Jan Willem; van Eck, Mirjam; van Meeteren, Jetty; Smits, Dirk Wouter; Twisk, Jos W.; Dallmeijer, Annet J.

    Objective: To examine associations over longitudinal measurements between neuromusculoskeletal function and gross motor capacity in children and youth with cerebral palsy (CP). Design: A prospective cohort study. Setting: Rehabilitation departments of university medical centers and rehabilitations

  15. Longitudinal Association Between Gross Motor Capacity and Neuromusculoskeletal Function in Children and Youth With Cerebral Palsy

    NARCIS (Netherlands)

    Vos, Rimke C.; Becher, Jules G.; Voorman, Jeanine M.; Gorter, Jan Willem; van Eck, Mirjam; van Meeteren, Jetty; Smits, Dirk Wouter; Twisk, Jos W.; Dallmeijer, Annet J.; van Schie, P. E M; Schuengel, C.; Ketelaar, M.; Lindeman, E.; Jongmans, M.; Roebroeck, M. E.; Tan, S. S.; Wiegerink, D. J H G; Reinders-Messelink, H. A.; Verheijden, J.

    2016-01-01

    Objective To examine associations over longitudinal measurements between neuromusculoskeletal function and gross motor capacity in children and youth with cerebral palsy (CP). Design A prospective cohort study. Setting Rehabilitation departments of university medical centers and rehabilitations

  16. Repetitive bilateral arm training with rhythmic auditory cueing improves motor function in chronic hemiparetic stroke

    National Research Council Canada - National Science Library

    Whitall, J; McCombe Waller, S; Silver, K H; Macko, R F

    2000-01-01

    ...) will improve motor function in the hemiparetic arm of stroke patients. In this single group pilot study we determined the effects of 6 weeks of BATRAC on 14 patients with chronic hemiparetic stroke...

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

    National Research Council Canada - National Science Library

    Nordbye-Nielsen, Kirsten; Kesmodel, Ulrik Schiøler

    2014-01-01

    .... 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...

  18. Angiogenic microspheres promote neural regeneration and motor function recovery after spinal cord injury in rats

    National Research Council Canada - National Science Library

    Yu, Shukui; Yao, Shenglian; Wen, Yujun; Wang, Ying; Wang, Hao; Xu, Qunyuan

    2016-01-01

    ... (bFGF) encapsulated in angiogenic microspheres. These spheres were delivered to sites of spinal cord contusion injury in rats, and their ability to induce vessel formation, neural regeneration and improve hindlimb motor function was assessed...

  19. Environmental Exposure to Manganese in Air: Associations with Tremor and Motor Function

    Science.gov (United States)

    BACKGROUND: Manganese (Mn) inhalation has been associated with neuropsychological and neurological sequelae in exposed workers. Few environmental epidemiologic studies have examined the potentialy neurotoxic effects of Mn exposure in ambient air on motor function and han...

  20. Executive Functions and Motor Ability Contribute to Children's Participation in Daily Activities

    Science.gov (United States)

    Rosenberg, Limor; Jacobi, Shani; Bart, Orit

    2017-01-01

    Executive functions are crucial for efficient daily functioning. However, the contribution of executive functions to the participation in daily life activities of children, have been inadequately studied. The study aimed to examine the unique contribution of executive functions, beyond motor ability, to the diversity and independence of children's…

  1. 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

  2. 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

    2013-01-29

    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.

  3. DTI measures track and predict motor function outcomes in stroke rehabilitation utilizing BCI technology.

    Science.gov (United States)

    Song, Jie; Nair, Veena A; Young, Brittany M; Walton, Leo M; Nigogosyan, Zack; Remsik, Alexander; Tyler, Mitchell E; Farrar-Edwards, Dorothy; Caldera, Kristin E; Sattin, Justin A; Williams, Justin C; Prabhakaran, Vivek

    2015-01-01

    Tracking and predicting motor outcomes is important in determining effective stroke rehabilitation strategies. Diffusion tensor imaging (DTI) allows for evaluation of the underlying structural integrity of brain white matter tracts and may serve as a potential biomarker for tracking and predicting motor recovery. In this study, we examined the longitudinal relationship between DTI measures of the posterior limb of the internal capsule (PLIC) and upper-limb motor outcomes in 13 stroke patients (median 20-month post-stroke) who completed up to 15 sessions of intervention using brain-computer interface (BCI) technology. Patients' upper-limb motor outcomes and PLIC DTI measures including fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) were assessed longitudinally at four time points: pre-, mid-, immediately post- and 1-month-post intervention. DTI measures and ratios of each DTI measure comparing the ipsilesional and contralesional PLIC were correlated with patients' motor outcomes to examine the relationship between structural integrity of the PLIC and patients' motor recovery. We found that lower diffusivity and higher FA values of the ipsilesional PLIC were significantly correlated with better upper-limb motor function. Baseline DTI ratios were significantly correlated with motor outcomes measured immediately post and 1-month-post BCI interventions. A few patients achieved improvements in motor recovery meeting the minimum clinically important difference (MCID). These findings suggest that upper-limb motor recovery in stroke patients receiving BCI interventions relates to the microstructural status of the PLIC. Lower diffusivity and higher FA measures of the ipsilesional PLIC contribute toward better motor recovery in the stroke-affected upper-limb. DTI-derived measures may be a clinically useful biomarker in tracking and predicting motor recovery in stroke patients receiving BCI interventions.

  4. Influence of Previous Comorbidities and Common Complications on Motor Function after Early Surgical Treatment of Patients with Traumatic Spinal Cord Injury.

    Science.gov (United States)

    Kreinest, Michael; Ludes, Lisa; Biglari, Bahram; Küffer, Maike; Türk, Ansgar; Grützner, Paul A; Matschke, Stefan

    2016-12-15

    The influence of complications and comorbidities on the outcome of patients with traumatic spinal cord injury after early surgery is unclear. The aim of the current study was to analyze the influence of previous comorbidities and common complications on motor function outcome of patients with traumatic spinal cord injury if early surgery was performed. All patients with a traumatic spinal cord injury who were initially surgically treated in our hospital in the period from January 2008 to December 2013 were included in this study. Epidemiological data and previous comorbidities (cardiovascular, pulmonary, metabolic, spinal) were documented. A neurological assessment was performed using the American Spinal Injury Association (ASIA) score. Retrospectively, patients' personal data (age, gender, comorbidities) and clinical data (complications, ASIA score, motor function) were analyzed statistically. A total of 133 patients met the inclusion criteria. The level of spinal cord injury ranged from C3 to L4. Motor function was improved from 51.5 ± 24.8 to 60.1 ± 25.0 (improvement: 25.7%). The most common complications were urinary tract infection and pneumonia. There is a significant relationship between a lack of previous spinal comorbidities and a better outcome in terms of motor function. No other comorbidities or complications showed any effect on motor function outcome. The current study shows that motor function was able to be improved in patients who were given early surgery after a traumatic spinal cord injury. Common complications as well as previous cardiovascular, pulmonary, and metabolic comorbidities do not impair motor function outcome. The final motor function score is reduced if patients have previous spinal comorbidities.

  5. Motor function measure scale, steroid therapy and patients with Duchenne muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Elaine C. da Silva

    2012-03-01

    Full Text Available OBJECTIVE: To assess the evolution of motor function in patients with Duchenne muscular dystrophy (DMD treated with steroids (prednisolone or deflazacort through the Motor Function Measure (MFM, which evaluates three dimensions of motor performance (D1, D2, D3. METHODS: Thirty-three patients with DMD (22 ambulant, 6 non-ambulant and 5 who lost the capacity to walk during the period of the study were assessed using the MFM scale six times over a period of 18 months. RESULTS: All the motor functions remained stable for 14 months in all patients, except D1 for those who lost their walking ability. In ambulant patients, D2 (axial and proximal motor capacities motor functions improved during six months; an improvement in D3 (distal motor capacity was noted during the total follow-up. D1 (standing posture and transfers and total score were useful to predict the loss of the ability to walk. CONCLUSIONS: The use of the MFM in DMD patients confirms the benefits of the steroid treatment for slowing the progression of the disease.

  6. 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...

  7. Shaping Early Reorganization of Neural Networks Promotes Motor Function after Stroke.

    OpenAIRE

    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 e...

  8. The Functional Integration in the Sensory-Motor System Predicts Aging in Healthy Older Adults

    OpenAIRE

    He, Hui; Luo, Cheng; Chang, Xin; Shan, Yan; Cao, Weifang; Gong, Jinnan; Klugah-Brown, Benjamin; Bobes, Maria A.; Biswal, Bharat; Yao, Dezhong

    2017-01-01

    Healthy aging is typically accompanied by a decrease in the motor capacity. Although the disrupted neural representations and performance of movement have been observed in older age in previous studies, the relationship between the functional integration of sensory-motor (SM) system and aging could be further investigated. In this study, we examine the impact of healthy aging on the resting-state functional connectivity (rsFC) of the SM system, and investigate as to how aging is affecting the...

  9. The efficacy of mirror therapy combined with conventional stroke rehabilitation program on motor and functional recovery

    OpenAIRE

    Selen Kuzgun; Merih Özgen; Onur Armağan; Funda Taşcıoğlu; Canan Baydemir

    2012-01-01

    OBJECTIVE: A variety of methods is used in the treatment of upper extremity functional impairment after stroke.In recent years, a new therapeutic approach in the treatment of stroke rehabilitation is the mirror therapy.The purpose of this study is to investigate the efficacy of mirror therapy,which is applied through motor imagination training, combined with conventional stroke rehabilitation program on upper extremity motor and functional recovery in patients with subacute stroke...

  10. A DIRECT CURRENT MOTOR WITH NO CONTACTS AND A TRANSISTOR COMMUTATOR.

    Science.gov (United States)

    dc motor of low power in which the collector is replaced by a transistor commutator controlled by a transformer sensor of the position of the rotor with respect to the stator. The rotor of the motor consists of a 2-pole permanent magnet. The transistor commutator of the motor may be used as a power amplifier. Control of motor speed is easily accomplished by means of modulating the input signals to the commutator. The motor is controlled by signals of low power which makes it possible to use it in automatic control systems without the use of very powerful additional

  11. Desing and Real-Time Analysis of a Direct Current Motor Controller

    Directory of Open Access Journals (Sweden)

    Reinier Torres Labrada

    2011-10-01

    Full Text Available The real time analysis of a DC motor controller is addressed. During the functional analysis, deadline and period of tasks were extracted to be used as parameters for Response Time Analysis (RTA. To get the Worst Case Execution Time (WCET each task is stimulated with a random input vector. A great number of computation time samples were recorded and the WCET computed using the Gumbel statistical distribution. With the WCET, deadlines and periods of the task set under analysis a RTA model is evaluated and its results discussed. By modeling the WCET using the Extreme Values Theory (EVT the need of low level analysis for software and an accurate model for hardware is avoided. The method used here is useful for soft real-time systems and could be applied to other hw/sw platforms easily.

  12. 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.

  13. Wolf Motor Function Test for Characterizing Moderate to Severe Hemiparesis in Stroke Patients

    Science.gov (United States)

    Hodics, Timea M.; Nakatsuka, Kyle; Upreti, Bhim; Alex, Arun; Smith, Patricia S.; Pezzullo, John C.

    2012-01-01

    Objective To extend the applicability of the Wolf Motor Function test (WMFT) to describe the residual functional abilities of moderate-to-severely affected stroke patients. The WMFT is a motor function test for mild to moderate upper extremity weakness in stroke patients, but it has not been routinely used for evaluation of more severe hemiparetic stroke patients due to its numerical characteristics. Design Data was collected as part of two double-blind sham controlled randomized interventional studies, the Transcranial Direct Current Stimulation (tDCS) in Chronic Stroke Recovery and tDCS Enhanced Stroke Recovery and Cortical Reorganization. Stroke patients were evaluated with the upper-extremity Fugl-Meyer (UFM) and the WMFT in the same setting prior to treatment. Setting University inpatient rehabilitation and outpatient clinic. Participants 32 stroke patients with moderate-to-severe hemiparesis enrolled in the tDCS in Chronic Stroke Recovery and tDCS Enhanced Stroke Recovery and Cortical Reorganization studies. Intervention Not applicable. Main Outcome Measures WMFT scores were calculated using 1) median performance times, 2) new calculation using the mean rate of performance. We compared the distribution of values from the two methods and examined the WMFT-UFM correlation for the traditional and the new calculation. Results WMFT rate values were more evenly distributed across their range than median WMFT time scores. The association between the WMFT rate and UFM was as good as the association between the median WMFT time scores and UFM (Spearman rs 0.84 vs −0.79). Conclusions The new WMFT mean rate of performance is valid and a more sensitive measure in describing the functional activities of the moderate to severely affected upper extremity of stroke subjects and avoids the pitfalls of the median WMFT time calculations. PMID:22579647

  14. 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

  15. Current Strategies in Cardiovascular Biomaterial Functionalization

    Directory of Open Access Journals (Sweden)

    Karla Lehle

    2010-01-01

    Full Text Available Prevention of the coagulation cascade and platelet activation is the foremost demand for biomaterials in contact with blood. In this review we describe the underlying mechanisms of these processes and offer the current state of antithrombotic strategies. We give an overview of methods to prevent protein and platelet adhesion, as well as techniques to immobilize biochemically active molecules on biomaterial surfaces. Finally, recent strategies in biofunctionalization by endothelial cell seeding as well as their possible clinical applications are discussed.

  16. Decoding post-stroke motor function from structural brain imaging

    Directory of Open Access Journals (Sweden)

    Jane M. Rondina

    2016-01-01

    Full Text Available Clinical research based on neuroimaging data has benefited from machine learning methods, which have the ability to provide individualized predictions and to account for the interaction among units of information in the brain. Application of machine learning in structural imaging to investigate diseases that involve brain injury presents an additional challenge, especially in conditions like stroke, due to the high variability across patients regarding characteristics of the lesions. Extracting data from anatomical images in a way that translates brain damage information into features to be used as input to learning algorithms is still an open question. One of the most common approaches to capture regional information from brain injury is to obtain the lesion load per region (i.e. the proportion of voxels in anatomical structures that are considered to be damaged. However, no systematic evaluation has yet been performed to compare this approach with using patterns of voxels (i.e. considering each voxel as a single feature. In this paper we compared both approaches applying Gaussian Process Regression to decode motor scores in 50 chronic stroke patients based solely on data derived from structural MRI. For both approaches we compared different ways to delimit anatomical areas: regions of interest from an anatomical atlas, the corticospinal tract, a mask obtained from fMRI analysis with a motor task in healthy controls and regions selected using lesion-symptom mapping. Our analysis showed that extracting features through patterns of voxels that represent lesion probability produced better results than quantifying the lesion load per region. In particular, from the different ways to delimit anatomical areas compared, the best performance was obtained with a combination of a range of cortical and subcortical motor areas as well as the corticospinal tract. These results will inform the appropriate methodology for predicting long term motor outcomes

  17. Molecular and Functional Characterization of the Developing Respiratory Motor Circuit

    OpenAIRE

    2015-01-01

    The faithful and sophisticated control of motor neurons (MNs) allows for our ability to walk, chew, breathe, and speak. This dissertation is focused on the characterization of MNs and the intricate circuitry that are involved in the control of these MNs that surround the airways. The relevance of this study goes beyond satisfying our curiosity of the physiology of breathing. This knowledge is critical in their application in respiratory medicine and speech rehabilitation – as the same set of ...

  18. Threat effects on human oculo-motor function.

    Science.gov (United States)

    Naranjo, E N; Cleworth, T W; Allum, J H J; Inglis, J T; Lea, J; Westerberg, B D; Carpenter, M G

    2017-09-17

    Neuro-anatomical evidence supports the potential for threat-related factors, such as fear, anxiety and vigilance, to influence brainstem motor nuclei controlling eye movements, as well as the vestibular nuclei. However, little is known about how threat influences human ocular responses, such as eye saccades (ES), smooth pursuit eye tracking (SP), and optokinetic nystagmus (OKN), and whether these responses can be facilitated above normal baseline levels with a natural source of threat. This study was designed to examine the effects of height-induced postural threat on the gain of ES, SP and OKN responses in humans. Twenty participants stood at two different surface heights while performing ES (ranging from 8° to 45° from center), SP (15, 20, 30°/s) and OKN (15, 30, 60°/s) responses in the horizontal plane. Height did not significantly increase the slope of the relationship between ES peak velocity and initial amplitude, or the gain of ES amplitude. In contrast height significantly increased SP and OKN gain. Significant correlations were found between changes in physiological arousal and OKN gain. Observations of changes with height in OKN and SP support neuro-anatomical evidence of threat-related mechanisms influencing both oculo-motor nuclei and vestibular reflex pathways. Although further study is warranted, the findings suggest that potential influences of fear, anxiety and arousal/alertness should be accounted for, or controlled, during clinical vestibular and oculo-motor testing. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Motor and Executive Function Profiles in Adult Residents ...

    Science.gov (United States)

    Objective: Exposure to elevated levels of manganese (Mn) may be associated with tremor, motor and executive dysfunction (EF), clinically resembling Parkinson’s disease (PD). PD research has identified tremor-dominant (TD) and non-tremor dominant (NTD) profiles. NTD PD presents with bradykinesia, rigidity, and postural sway, and is associated with EF impairment with lower quality of life (QoL). Presence and impact of tremor, motor, and executive dysfunction profiles on health-related QoL and life satisfaction were examined in air-Mn exposed residents of two Ohio, USA towns. Participants and Methods: From two Ohio towns exposed to air-Mn, 186 residents (76 males) aged 30-75 years were administered measures of EF (Animal Naming, ACT, Rey-O Copy, Stroop Color-Word, and Trails B), motor and tremor symptoms (UPDRS), QoL (BRFSS), life satisfaction (SWLS), and positive symptom distress (SCL-90-R). Air-Mn exposure in the two towns was modeled with 10 years of air-monitoring data. Cluster analyses detected the presence of symptom profiles by grouping together residents with similar scores on these measures. Results: Overall, mean air-Mn concentration for the two towns was 0.53 µg/m3 (SD=.92). Two-step cluster analyses identified TD and NTD symptom profiles. Residents in the NTD group lacked EF impairment; EF impairment represented a separate profile. An unimpaired group also emerged. The NTD and EF impairment groups were qualitatively similar, with relatively lo

  20. Association of therapeutic occasion, gross motor function grading and developmental level with gross motor functional recovery in children with cerebral palsy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: The abnormal posture and motor pattern have not stabilized in children with cerebral palsy at early period, thus timely treatment can establish normal postural reflex and motor pattern, and prevent complications of muscle contracture, ankylosis, skeletal deformity, etc. The clinical factors affecting the rehabilitative efficacy of gross motor function in children with cerebral palsy should be observed.OBJECTIVE: To observe the effects of therapeutic occasion, grading of gross motor function and developmental level on the rehabilitative efficacy in children with cerebral palsy.DESIGN: A case-controlled analysis.SETTING: Qilu Children's Hospital of Shandong University.PARTICIPANTS: Totally 138 children with cerebral palsy, who were hospitalized for 12 months in the Rehabilitation Center of Qilu Children's Hospital, Shandong University, were selected from April 2004 to September 2006, and all the children were diagnosed to be accorded with the standard set by the national seminar on cerebral palsy in 2004. There were 97 males and 41 females, including 55 cases of 0 - 2 years old,47 cases of 2 - 4 years and 36 cases of 4 - 6 years. Informed contents were obtained from relatives of all the children.METHODS: ① Comprehensive rehabilitation treatment: Vojta method was to induce the children to turn over the body and crawl by stimulating reflective turn over and crawling on belly. Bobath method including trainings of head control, turning over body, keeping sitting position, keeping balance, crawling, keeping standing position, and walking, etc.; The children were massaged by using the maneuvers of push, press, rub,pull, wave, etc. according to the sites and types of palsy. Acupuncture was performed mainly at bilateral motor areas, the needle was retained for 1 hour per time, 6 days continuously every week, and followed by a 1-day interval. ② Prognosis assessment: The gross motor functional grading of the children with cerebral palsy at admission was

  1. Optically-Induced Neuronal Activity Is Sufficient to Promote Functional Motor Axon Regeneration In Vivo.

    Directory of Open Access Journals (Sweden)

    Patricia J Ward

    Full Text Available Peripheral nerve injuries are common, and functional recovery is very poor. Beyond surgical repair of the nerve, there are currently no treatment options for these patients. In experimental models of nerve injury, interventions (such as exercise and electrical stimulation that increase neuronal activity of the injured neurons effectively enhance axon regeneration. Here, we utilized optogenetics to determine whether increased activity alone is sufficient to promote motor axon regeneration. In thy-1-ChR2/YFP transgenic mice in which a subset of motoneurons express the light-sensitive cation channel, channelrhodopsin (ChR2, we activated axons in the sciatic nerve using blue light immediately prior to transection and surgical repair of the sciatic nerve. At four weeks post-injury, direct muscle EMG responses evoked with both optical and electrical stimuli as well as the ratio of these optical/electrical evoked EMG responses were significantly greater in mice that received optical treatment. Thus, significantly more ChR2+ axons successfully re-innervated the gastrocnemius muscle in mice that received optical treatment. Sections of the gastrocnemius muscles were reacted with antibodies to Synaptic Vesicle Protein 2 (SV2 to quantify the number of re-occupied motor endplates. The number of SV2+ endplates was greater in mice that received optical treatment. The number of retrogradely-labeled motoneurons following intramuscular injection of cholera toxin subunit B (conjugated to Alexa Fluor 555 was greater in mice that received optical treatment. Thus, the acute (1 hour, one-time optical treatment resulted in robust, long-lasting effects compared to untreated animals as well as untreated axons (ChR2-. We conclude that neuronal activation is sufficient to promote motor axon regeneration, and this regenerative effect is specific to the activated neurons.

  2. Altered structural and functional connectivity between the bilateral primary motor cortex in unilateral subcortical stroke

    Science.gov (United States)

    Zhang, Yong; Li, Kuang-Shi; Ning, Yan-Zhe; Fu, Cai-Hong; Liu, Hong-Wei; Han, Xiao; Cui, Fang-Yuan; Ren, Yi; Zou, Yi-Huai

    2016-01-01

    Abstract A large number of functional imaging studies have focused on the understanding of motor-related neural activities after ischemic stroke. However, the knowledge is still limited in the structural and functional changes of the interhemispheric connections of the bilateral primary motor cortices (M1s) and their potential influence on motor function recovery following stroke. Twenty-four stroke patients with right hemispheric subcortical infarcts and 25 control subjects were recruited to undergo multimodal magnetic resonance imaging examinations. Structural impairments between the bilateral M1s were measured by fractional anisotropy. Functional changes of the bilateral M1s were assessed via M1-M1 resting-state functional connectivity. Task-evoked activation analysis was applied to identify the roles of the bilateral hemispheres in motor function recovery. Compared with control subjects, unilateral subcortical stroke patients revealed significantly decreased fractional anisotropy and functional connectivity between the bilateral M1s. Stroke patients also revealed higher activations in multiple brain regions in both hemispheres and that more regions were located in the contralesional hemisphere. This study increased our understanding of the structural and functional alterations between the bilateral M1s that occur in unilateral subcortical stroke and provided further evidence for the compensatory role played by the contralesional hemisphere for these alterations during motor function recovery. PMID:27495109

  3. Minimization and identification of conducted emission bearing current in variable speed induction motor drives using PWM inverter

    Indian Academy of Sciences (India)

    A Ramachandran; M Channa Reddy; Ranjan Moodithaya

    2008-10-01

    The recent increase in the use of speed control of ac induction motor for variable speed drive using pulse width modulation (PWM) inverter is due to the advent of modern power electronic devices and introduction of microprocessors. There are many advantages of using ac induction motor for speed control applicatons in process and aerospace industries, but due to fast switching of the modern power electronic devices, the parasitic coupling produces undesirable effects. The undesirable effects include radiated and conducted electromagnetic interference (EMI) which adversely affect nearby computers, electronic/electrical instruments and give rise to the flow of bearing current in the induction motor. Due to the flow of bearing current in the induction motor, electrical discharge machining takes place in the inner race of the bearing which reduces the life of the bearing. In high power converters and inverters, the conducted and radiated emissions become a major concern. In this paper, identification of bearing current due to conducted emission, the measurement of bearing current in a modified induction motor and to minimize the bearing current are discussed. The standard current probe, the standard line impedance stabilization network (LISN)), the electronics interface circuits are used to measure high frequency common mode current, bearing current and to minimize the conducted noise from the system. The LISN will prevent the EMI noise entering the system from the supply source by conductive methods, at the same time prevents the EMI generated if any due to PWM, fast switching in the system, will not be allowed to enter the supply line. For comparing the results with Federal Communications Commission (FCC) and Special Committee on Radio Interference (CISPR) standards, the graphs are plotted with frequency Vs, line voltage in $dB{_\\mu} V$, common mode voltage in $dB{_\\mu} V$ and the bearing current in $dB_{\\mu} A$ with out and with minimizing circuits.

  4. tDCS-enhanced motor and cognitive function in neurological diseases.

    Science.gov (United States)

    Flöel, Agnes

    2014-01-15

    Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation tool that is now being widely used in neuroscientific and clinical research in humans. While initial studies focused on modulation of cortical excitability, the technique quickly progressed to studies on motor and cognitive functions in healthy humans and in patients with neurological diseases. In the present review we will first provide the reader with a brief background on the basic principles of tDCS. In the main part, we will outline recent studies with tDCS that aimed at enhancing behavioral outcome or disease-specific symptoms in patients suffering from mild cognitive impairment, Alzheimer's disease, movement disorders, and epilepsy, or persistent deficits after stroke. The review will close with a summary statement on the present use of tDCS in the treatment of neurological disorders, and an outlook to further developments in this realm. tDCS may be an ideal tool to be administered in parallel to intensive cognitive or motor training in neurological disease, but efficacy for the areas of activities and participation still needs to be established in controlled randomized trials. Its use in reducing disease-specific symptoms like dystonia or epileptic seizures is still unclear.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. [Peculiarities of the structural-functional organization of motor neuropil of dragonfly thoracic ganglia].

    Science.gov (United States)

    Plotnikova, S I; Sviderskiĭ, V L; Gorelkin, V S

    2012-01-01

    The work considers the structural-functional relations existing in the motor neuropil of thoracic ganglia of dragonflies - the animals able to perform very complex and fast maneuvers in the flight. The motor neuropil in dragonflies is shown to be more differentiated than in the lees mobile insects, while motor nuclei in neuropil are more clearly outlined and closer to each other. There are revealed dendrites of motoneurons of pedal muscles (the middle nucleus), which are running into the anterior and posterior nuclei that contain dendrites of motoneurons of wing muscles. A possible role of such approaching is discussed for close functional interaction of wing and foot muscles, which is necessary to dragonflies during flight at their catching of large insects with aid of legs. Peculiarities are considered in structural organization of motoneurons of wing muscles dragonflies and locusts, which indicate the greater functional possibilities peculiar to motoneurons of the dragonflies motor apparatus.

  7. A prototype symbolic model of canonical functional neuroanatomy of the motor system.

    Science.gov (United States)

    Talos, Ion-Florin; Rubin, Daniel L; Halle, Michael; Musen, Mark; Kikinis, Ron

    2008-04-01

    Recent advances in bioinformatics have opened entire new avenues for organizing, integrating and retrieving neuroscientific data, in a digital, machine-processable format, which can be at the same time understood by humans, using ontological, symbolic data representations. Declarative information stored in ontological format can be perused and maintained by domain experts, interpreted by machines, and serve as basis for a multitude of decision support, computerized simulation, data mining, and teaching applications. We have developed a prototype symbolic model of canonical neuroanatomy of the motor system. Our symbolic model is intended to support symbolic look up, logical inference and mathematical modeling by integrating descriptive, qualitative and quantitative functional neuroanatomical knowledge. Furthermore, we show how our approach can be extended to modeling impaired brain connectivity in disease states, such as common movement disorders. In developing our ontology, we adopted a disciplined modeling approach, relying on a set of declared principles, a high-level schema, Aristotelian definitions, and a frame-based authoring system. These features, along with the use of the Unified Medical Language System (UMLS) vocabulary, enable the alignment of our functional ontology with an existing comprehensive ontology of human anatomy, and thus allow for combining the structural and functional views of neuroanatomy for clinical decision support and neuroanatomy teaching applications. Although the scope of our current prototype ontology is limited to a particular functional system in the brain, it may be possible to adapt this approach for modeling other brain functional systems as well.

  8. Plasticity of motor function and surgical outcomes in patients with cerebral arteriovenous malformation involving primary motor area:insight from fMRI and DTI

    Institute of Scientific and Technical Information of China (English)

    Lijun Wang; Fuxin Lin; Jun Wu; Yuming Jiao; Yong Cao; Yuanli Zhao; Shuo Wang

    2016-01-01

    Background:Patients who have a cerebral arteriovenous malformation (cAVMs) in the motor cortex can have displaced function. The finding and its relationship to recovery from surgery is not known. Methods:We present the five cases with cAVMs involving precentral knob and/or paracentral lobule and without preoperative motor deficits. We used motor activation areas derived from Functional functional MRI (fMRI) as a region of interesting (ROI) to launch the plasticity of cerebrospinal tracts (CST). All the results were incorporated into the neuronavigation platform for surgical treatment. Intraoperative electric cortical stimulation (ECS) was used to map motor areas. Modified Rankin Scale (mRS) of hands and feets were performed on postoperative day 2, 7 and at month 3, 6 during follow-up period. All the patients suffered from motor deficits regardless of cortical activation patterns. Results:Three patients showed functionally seeded CST in or around the AVM, and were validated by intraoperative electrical stimulation (ECS). Patient 4 had two aberrant functionally seeded fiber tracts away from the lesion, but were proved to be non-functional by postoperative motor deficits. Patient 3 with motor cortex and fiber tract within a diffuse AVMs nidus, complete paralysis of upper extremity after operation and has a persistent motor deficit during 6-month follow-up period. Conclusions:The plasticity of motor cortex on fMRI doesn’t prevent post-operative motor deficits. Functionally mapped fiber tract within or abutting AVM nidus predicts transient and persistent motor deficit.

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

    Science.gov (United States)

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

    2016-05-17

    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 method to obtain new and functionalizable overcrowded alkenes in enantiopure form is presented. The procedure involves a short synthesis of three steps and a solvent-switchable chiral resolution by using a readily available resolving agent. X-ray crystallography revealed the mode of binding of the motor with the resolving agent, as well as the absolute configuration of the motor. (1) H NMR and UV/Vis spectroscopy techniques were used to determine the dynamic behavior of this molecular motor. This method provides rapid access to ample amounts of enantiopure molecular motors, which will greatly facilitate the further development of responsive molecular systems based on chiral overcrowded alkenes.

  10. Motor cortex excitability and connectivity in chronic stroke: a multimodal model of functional reorganization.

    Science.gov (United States)

    Volz, Lukas J; Sarfeld, Anna-Sophia; Diekhoff, Svenja; Rehme, Anne K; Pool, Eva-Maria; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

    2015-03-01

    Cerebral ischemia triggers a cascade of cellular processes, which induce neuroprotection, inflammation, apoptosis and regeneration. At the neural network level, lesions concomitantly induce cerebral plasticity. Yet, many stroke survivors are left with a permanent motor deficit, and only little is known about the neurobiological factors that determine functional outcome after stroke. Transcranial magnetic stimulation (TMS) and magnetic resonance imaging (MRI) are non-invasive approaches that allow insights into the functional (re-) organization of the cortical motor system. We here combined neuronavigated TMS, MRI and analyses of connectivity to investigate to which degree recovery of hand function depends on corticospinal tract (CST) damage and biomarkers of cerebral plasticity like cortical excitability and motor network effective connectivity. As expected, individual motor performance of 12 stroke patients with persistent motor deficits was found to depend upon the degree of CST damage but also motor cortex excitability and interhemispheric connectivity. In addition, the data revealed a strong correlation between reduced ipsilesional motor cortex excitability and reduced interhemispheric inhibition in severely impaired patients. Interindividual differences in ipsilesional motor cortex excitability were stronger related to the motor deficit than abnormal interhemispheric connectivity or CST damage. Multivariate linear regression analysis combining the three factors accounted for more than 80 % of the variance in functional impairment. The inter-relation of cortical excitability and reduced interhemispheric inhibition provides direct multi-modal evidence for the disinhibition theory of the contralesional hemisphere following stroke. Finally, our data reveal a key mechanism (i.e., the excitability-related reduction in interhemispheric inhibition) accounting for the rehabilitative potential of novel therapeutic approaches which aim at modulating cortical

  11. Impairments of motor-cortex responses to unilateral and bilateral direct current stimulation in schizophrenia

    Directory of Open Access Journals (Sweden)

    Alkomiet eHasan

    2013-10-01

    Full Text Available Transcranial direct current stimulation (tDCS is a non-invasive stimulation technique that can be applied to modulate cortical activity through induction of cortical plasticity. Since various neuropsychiatric disorders are characterised by fluctuations in cortical activity levels (e.g. schizophrenia, tDCS is increasingly investigated as a treatment tool. Several studies have shown that the induction of cortical plasticity following classical, unilateral tDCS is reduced or impaired in the stimulated and non-stimulated primary motor cortices (M1 of schizophrenia patients. Moreover, an alternative, bilateral tDCS setup has recently been shown to modulate cortical plasticity in both hemispheres in healthy subjects, highlighting another potential treatment approach. Here we present the first study comparing the efficacy of unilateral tDCS (cathode left M1, anode right supraorbital with simultaneous bilateral tDCS (cathode left M1, anode right M1 in schizophrenia patients. tDCS-induced cortical plasticity was monitored by investigating motor-evoked potentials induced by single-pulse transcranial magnetic stimulation applied to both hemispheres. Healthy subjects showed a reduction of left M1 excitability following unilateral tDCS on the stimulated left hemisphere and an increase in right M1 excitability following bilateral tDCS. In schizophrenia, no plasticity was induced following both stimulation paradigms. The pattern of these results indicates a complex interplay between plasticity and connectivity that is impaired in schizophrenia patients. Further studies are needed to clarify the biological underpinnings and clinical impact of these findings.

  12. Impairments of motor-cortex responses to unilateral and bilateral direct current stimulation in schizophrenia.

    Science.gov (United States)

    Hasan, Alkomiet; Bergener, Theresa; Nitsche, Michael A; Strube, Wolfgang; Bunse, Tilmann; Falkai, Peter; Wobrock, Thomas

    2013-01-01

    Transcranial direct current stimulation (tDCS) is a non-invasive stimulation technique that can be applied to modulate cortical activity through induction of cortical plasticity. Since various neuropsychiatric disorders are characterized by fluctuations in cortical activity levels (e.g., schizophrenia), tDCS is increasingly investigated as a treatment tool. Several studies have shown that the induction of cortical plasticity following classical, unilateral tDCS is reduced or impaired in the stimulated and non-stimulated primary motor cortices (M1) of patients with schizophrenia. Moreover, an alternative, bilateral tDCS setup has recently been shown to modulate cortical plasticity in both hemispheres in healthy subjects, highlighting another potential treatment approach. Here we present the first study comparing the efficacy of unilateral tDCS (cathode left M1, anode right supraorbital) with simultaneous bilateral tDCS (cathode left M1, anode right M1) in patients with schizophrenia. tDCS-induced cortical plasticity was monitored by investigating motor-evoked potentials induced by single-pulse transcranial magnetic stimulation applied to both hemispheres. Healthy subjects showed a reduction of left M1 excitability following unilateral tDCS on the stimulated left hemisphere and an increase in right M1 excitability following bilateral tDCS. In schizophrenia, no plasticity was induced following both stimulation paradigms. The pattern of these results indicates a complex interplay between plasticity and connectivity that is impaired in patients with schizophrenia. Further studies are needed to clarify the biological underpinnings and clinical impact of these findings.

  13. How does the motor relearning program improve neurological function of brain ischemia monkeys?

    Institute of Scientific and Technical Information of China (English)

    Yong Yin; Zhongtang Feng; Zhen Gu; Lei Pan; Lu Gan; Dongdong Qin; Bo Yang; Jin Guo; Xintian Hu; Tinghua Wang

    2013-01-01

    The motor relearning program can significantly improve various functional disturbance induced by ischemic cerebrovascular diseases. However, its mechanism of action remains poorly understood. In injured brain tissues, glial fibrillary acidic protein and neurofilament protein changes can reflect the condition of injured neurons and astrocytes, while vascular endothelial growth factor and basic fibroblast growth factor changes can indicate angiogenesis. In the present study, we induced ischemic brain injury in the rhesus macaque by electrocoagulation of the M1 segment of the right middle cerebral artery. The motor relearning program was conducted for 60 days from the third day after model establishment. Immunohistochemistry and single-photon emission CT showed that the numbers of glial fibrillary acidic protein-, neurofilament protein-, vascular endothelial growth factorand basic fibroblast growth factor-positive cells were significantly increased in the infarcted side compared with the contralateral hemisphere following the motor relearning program. Moreover, cerebral blood flow in the infarcted side was significantly improved. The clinical rating scale for stroke was used to assess neurological function changes in the rhesus macaque following the motor relearning program. Results showed that motor function was improved, and problems with consciousness, self-care ability and balance function were significantly ameliorated. These findings indicate that the motor relearning program significantly promoted neuronal regeneration, repair and angiogenesis in the surroundings of the infarcted hemisphere, and improve neurological function in the rhesus macaque following brain ischemia.

  14. Current management of motor fluctuations in patients with advanced Parkinson's disease treated chronically with levodopa.

    Science.gov (United States)

    Melamed, E; Zoldan, J; Galili-Mosberg, R; Ziv, I; Djaldetti, R

    1999-01-01

    effective pharmacological treatment for Parkinson's disease (Melamed, 1987). Undoubtedly, the outstanding therapeutic success of levodopa represents a dramatic and revolutionary breakthrough in medicine, in general, and in neurology, in particular. Although, since the introduction of levodopa, there have been many additional pharmacological and even surgical anti-parkinsonian strategies, it still stands out as a mandatory axis of treatment in the majority of patients (Steigler and Quinn, 1992). Indeed, levodopa therapy improves, sometimes markedly, the motor signs and symptoms of the illness, the functional capacity and quality of life and perhaps also life expectancy of the afflicted patients. It is therefore unfortunate that after an initial problem-free period of successful, smooth and stable clinical benefit from levodopa that lasts about two to five years, the responsiveness of many patients worsens with the emergence of a variety of complications (Marsden et al., 1982; Hardie et al., 1984). These adverse reactions include dyskinesias and dystonias, psychotic problems and, particularly, the troublesome motor fluctuations (Marsden and Parkes, 1977; Marsden, 1994). The latter phenomenon may be particularly complex, limiting and disabling. It is believed that most patients on long-term levodopa therapy will, sooner or later, develop response fluctuations of varying types and severity (Riley and Lang, 1993). Because of the serious impact of these phenomena on the quality of life and function of the patients, many efforts are now being undertaken to identify the responsible mechanisms and to devise preventive and therapeutic measures.

  15. Validación Experimental de la Metodología Motor Current Signature Analysis para un Motor de Inducción de 2 HP

    Directory of Open Access Journals (Sweden)

    Silvia J. Oviedo

    2014-01-01

    Full Text Available El análisis de las corrientes de estator en la monitorización de máquinas eléctricas rotativas, particularmente en motores de inducción, ha tenido un creciente interés, debido a que la información contenida en el espectro de la señal de corriente puede indicar la presencia de diversos tipos de fallas tanto eléctricas como mecánicas. En este trabajo se implementó un banco de pruebas para motores de inducción de 2 HP con el fin de validar la metodología MCSA (Motor Current Signature Analysis para la detección de: corto circuito en el devanado del estator, barras de rotor rotas y excentricidad del entrehierro bajo distintas condiciones de carga. Los resultados dejan ver el grado de dependencia entre la condición de carga del motor con falla y la posibilidad de detección de la misma, así como evaluar la viabilidad de la implementación de dicha metodología en los esquemas de mantenimiento basado en la condición (CBM.

  16. Performance Evaluation of Photo-Voltaic fed Brushless Direct Current Motor for Agricultural applications

    Directory of Open Access Journals (Sweden)

    B.V.A.S.S.R.Krishna

    2015-10-01

    Full Text Available This work presents an effective approach towards reduction of steps in power conversion from solar photovoltaic system to load. When a Photovoltaic system is fed to an induction motor, it requires MPPT controller and an Inverter circuit in first and second stages since Induction motor works with a.c supply. By eliminating the Inverter circuit and employing a BLDC motor the efficiency of the system can be improved. The BLDC motor works under Electronic commutation principle with VSI embedded in the motor. A PV Panel fed to the "R" load with Hill Climbing MPPT is considered along with practical irradiance data. Simulation is carried out by formulating the mathematical model for the photovoltaic source, MPPT, Motor. System performance‟s are investigated under different levels of solar insolation

  17. Effects of functional physical activity on the maintenance of motor function in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Laís Fajersztajn

    Full Text Available Abstract It is widely known that older adults, even frail individuals, can improve their physical function using appropriately targeted exercise. Nevertheless, older adults with Alzheimer's disease (AD have been excluded from the majority of studies on exercise. The functional-task physical activity program is based on activities of daily living, and may be suited for elderly people with AD because it focuses on the maintenance and stimulation of preserved abilities. In addition, session costs are substantially reduced by adopting a group approach. Furthermore, the group approach may improve the social interaction of the demented patient. Objectives: To determine whether a functional-task physical activity program in groups can maintain motor function in elderly with AD. Methods: 10 elderly diagnosed with mild or moderate AD were assigned into one of two groups: subjects with and without intervention. The intervention consisted of a 12-week function-task physical activity program in groups. Measurements: activities of daily living (Katz and Lawton & Brody questionnaires, mobility (Timed Up and Go Test, Timed Up and Go manual Test and Timed Up and Go Cognitive Test, cognition (Mini-Mental State Examination, behavioral disturbances (Neuropsychiatric Inventory I-brief and functional balance (Berg Balance Scale. Results: A statistically significant difference between the two groups was found regarding the functional balance mean change measured by Berg scale score (p=0.046. A significant improvement of 1.60 points (95%CI[0.22;2.98] was observed in the intervention group on this scale, while the non-intervention group showed -0.40 points (95%CI[-1.78;0.98], no change. Conclusions: It is possible to treat mild and moderate Alzheimer's patients using a group approach. The functional task physical activity program was efficient in functional balance improvement and also appeared to prevent mobility decline.

  18. The relationship between executive function and fine motor control in young and older adults.

    Science.gov (United States)

    Corti, Emily J; Johnson, Andrew R; Riddle, Hayley; Gasson, Natalie; Kane, Robert; Loftus, Andrea M

    2017-01-01

    The present study examined the relationship between executive function (EF) and fine motor control in young and older healthy adults. Participants completed 3 measures of executive function; a spatial working memory (SWM) task, the Stockings of Cambridge task (planning), and the Intra-Dimensional Extra-Dimensional Set-Shift task (set-shifting). Fine motor control was assessed using 3 subtests of the Purdue Pegboard (unimanual, bimanual, sequencing). For the younger adults, there were no significant correlations between measures of EF and fine motor control. For the older adults, all EFs significantly correlated with all measures of fine motor control. Three separate regressions examined whether planning, SWM and set-shifting independently predicted unimanual, bimanual, and sequencing scores for the older adults. Planning was the primary predictor of performance on all three Purdue subtests. A multiple-groups mediation model examined whether planning predicted fine motor control scores independent of participants' age, suggesting that preservation of planning ability may support fine motor control in older adults. Planning remained a significant predictor of unimanual performance in the older age group, but not bimanual or sequencing performance. The findings are discussed in terms of compensation theory, whereby planning is a key compensatory resource for fine motor control in older adults. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Determinants of Functional Disability in Huntington’s Disease: Role of Cognitive and Motor Dysfunction

    Science.gov (United States)

    Ross, Christopher A.; Pantelyat, Alex; Kogan, Jane; Brandt, Jason

    2014-01-01

    The clinical syndrome of Huntington’s disease is notable for a triad of motor, cognitive and emotional features. All HD patients eventually become occupationally disabled; however the factors that render HD patients unable to maintain employment have not been extensively studied. This review begins by discussing the clinical triad of HD, highlighting the distinction in the motor disorder between involuntary movements such as chorea, and voluntary movement impairment, with the latter contributing more to functional disability. Cognitive disorder clearly contributes to disability, though the relative contribution compared to motor is difficult to unravel, especially since many of the tests used to asses “cognition” have a strong motor component. The role of emotional changes in disability needs more study. The literature on contributions to functional disability, driving impairment and nursing home placement is reviewed. Relevant experience is presented from the longstanding JHU HD observational study on motor vs cognitive onset, and on cognitive and motor features at the time when individuals discontinued working. Finally, we briefly review government policies in several countries on disability determination. We interpret the data from our own studies and from the literature to indicate that there is usually a close relationship between cognitive and motor dysfunction, and that it is critical to take both into consideration in determining disability. PMID:25216368

  20. Motor function at school age in children with a preschool diagnosis of developmental language impairment.

    Science.gov (United States)

    Webster, Richard I; Majnemer, Annette; Platt, Robert W; Shevell, Michael I

    2005-01-01

    To evaluate fine motor (FM) and gross motor (GM) function shortly after school entry in children with a preschool diagnosis of developmental language impairment (DLI). A cohort of children (n = 70) diagnosed at pre-school age with DLI was reevaluated in elementary school. Language, cognitive, and motor outcomes were assessed through the use of the Battelle Developmental Inventory (BDI). Language was further assessed through the use of the Vineland Adaptive Behavior Scale, Peabody Picture Vocabulary, and Expressive One Word Picture Vocabulary Tests. Performance below -1.5 SD of the normative mean on any test was considered to represent impairment. Forty-three children (mean age, 7.4 +/- 0.7 years) underwent reassessment at a mean of 3.8 +/- 0.7 years after initial preschool assessment. Mean scores for BDI motor domains (FM, 78.3 +/- 11.4; GM, 84.9 +/- 13.3) fell below normative values. Twenty-two children (52%) had motor impairment (FM, 17 of 42; GM, 15 of 42); 35 of 43 (81%) continued to have language impairment. BDI communication raw scores correlated most strongly with FM (rho = 0.73, P < .001) and GM (rho = 0.58, P = .003) raw scores but showed only moderate correlations with cognitive raw scores (rho = 0.41, P = .05). Impaired motor function is an important comorbidity in DLI. Factors critical to motor performance may also contribute to language deficits in DLI.

  1. IPLEX administration improves motor neuron survival and ameliorates motor functions in a severe mouse model of spinal muscular atrophy.

    Science.gov (United States)

    Murdocca, Michela; Malgieri, Arianna; Luchetti, Andrea; Saieva, Luciano; Dobrowolny, Gabriella; de Leonibus, Elvira; Filareto, Antonio; Quitadamo, Maria Chiara; Novelli, Giuseppe; Musarò, Antonio; Sangiuolo, Federica

    2012-09-25

    Spinal muscular atrophy (SMA) is an inherited neurodegenerative disorder and the first genetic cause of death in childhood. SMA is caused by low levels of survival motor neuron (SMN) protein that induce selective loss of α-motor neurons (MNs) in the spinal cord, resulting in progressive muscle atrophy and consequent respiratory failure. To date, no effective treatment is available to counteract the course of the disease. Among the different therapeutic strategies with potential clinical applications, the evaluation of trophic and/or protective agents able to antagonize MNs degeneration represents an attractive opportunity to develop valid therapies. Here we investigated the effects of IPLEX (recombinant human insulinlike growth factor 1 [rhIGF-1] complexed with recombinant human IGF-1 binding protein 3 [rhIGFBP-3]) on a severe mouse model of SMA. Interestingly, molecular and biochemical analyses of IGF-1 carried out in SMA mice before drug administration revealed marked reductions of IGF-1 circulating levels and hepatic mRNA expression. In this study, we found that perinatal administration of IPLEX, even if does not influence survival and body weight of mice, results in reduced degeneration of MNs, increased muscle fiber size and in amelioration of motor functions in SMA mice. Additionally, we show that phenotypic changes observed are not SMN-dependent, since no significant SMN modification was addressed in treated mice. Collectively, our data indicate IPLEX as a good therapeutic candidate to hinder the progression of the neurodegenerative process in SMA.

  2. Functional Magnetic Resonance Imaging of Motor Cortex: Hemispheric Asymmetry and Handedness

    Science.gov (United States)

    Kim, Seong-Gi; Ashe, James; Hendrich, Kristy; Ellermann, Jutta M.; Merkle, Hellmut; Ugurbil, Kamil; Georgopoulos, Apostolos P.

    1993-07-01

    A hemispheric asymmetry in the functional activation of the human motor cortex during contralateral (C) and ipsilateral (I) finger movements, especially in right-handed subjects, was documented with nuclear magnetic resonance imaging at high field strength (4 tesla). Whereas the right motor cortex was activated mostly during contralateral finger movements in both right-handed (C/I mean area of activation = 36.8) and left-handed (C/I = 29.9) subjects, the left motor cortex was activated substantially during ipsilateral movements in left-handed subjects (C/I = 5.4) and even more so in right-handed subjects (C/I = 1.3).

  3. Executive Function Is Associated With Off-Line Motor Learning in People With Chronic Stroke.

    Science.gov (United States)

    Al-Dughmi, Mayis; Al-Sharman, Alham; Stevens, Suzanne; Siengsukon, Catherine F

    2017-04-01

    Sleep has been shown to promote off-line motor learning in individuals following stroke. Executive function ability has been shown to be a predictor of participation in rehabilitation and motor recovery following stroke. The purpose of this study was to explore the association between executive function and off-line motor learning in individuals with chronic stroke compared with healthy control participants. Seventeen individuals with chronic stroke (>6 months poststroke) and 9 healthy adults were included in the study. Participants underwent 3 consecutive nights of polysomnography, practiced a continuous tracking task the morning of the third day, and underwent a retention test the morning after the third night. Participants underwent testing on 4 executive function tests after the continuous tracking task retention test. Participants with stroke showed a significant positive correlation between the off-line motor learning score and performance on the Trail-Making Test from Delis-Kaplan Executive Function System (r = 0.652; P = 0.005), while the healthy control participants did not. Regression analysis showed that the Trail-Making Test-Delis-Kaplan Executive Function System is a significant predictor of off-line motor learning (P = 0.008). This is the first study to demonstrate that better performance on an executive function test of attention and set-shifting predicts a higher magnitude of off-line motor learning in individuals with chronic stroke. This emphasizes the need to consider attention and set-shifting abilities of individuals following stroke as these abilities are associated with motor learning. This in turn could affect learning of activities of daily living and impact functional recovery following stroke.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A166).

  4. Functional Diversification of Motor Neuron-specific Isl1 Enhancers during Evolution.

    Directory of Open Access Journals (Sweden)

    Namhee Kim

    2015-10-01

    Full Text Available Functional diversification of motor neurons has occurred in order to selectively control the movements of different body parts including head, trunk and limbs. Here we report that transcription of Isl1, a major gene necessary for motor neuron identity, is controlled by two enhancers, CREST1 (E1 and CREST2 (E2 that allow selective gene expression of Isl1 in motor neurons. Introduction of GFP reporters into the chick neural tube revealed that E1 is active in hindbrain motor neurons and spinal cord motor neurons, whereas E2 is active in the lateral motor column (LMC of the spinal cord, which controls the limb muscles. Genome-wide ChIP-Seq analysis combined with reporter assays showed that Phox2 and the Isl1-Lhx3 complex bind to E1 and drive hindbrain and spinal cord-specific expression of Isl1, respectively. Interestingly, Lhx3 alone was sufficient to activate E1, and this may contribute to the initiation of Isl1 expression when progenitors have just developed into motor neurons. E2 was induced by onecut 1 (OC-1 factor that permits Isl1 expression in LMCm neurons. Interestingly, the core region of E1 has been conserved in evolution, even in the lamprey, a jawless vertebrate with primitive motor neurons. All E1 sequences from lamprey to mouse responded equally well to Phox2a and the Isl1-Lhx3 complex. Conversely, E2, the enhancer for limb-innervating motor neurons, was only found in tetrapod animals. This suggests that evolutionarily-conserved enhancers permit the diversification of motor neurons.

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

    Science.gov (United States)

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

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Aurore Thibaut

    2017-05-01

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

  7. The contributions of balance to gait capacity and motor function in chronic stroke.

    Science.gov (United States)

    Lee, Kyoung Bo; Lim, Seong Hoon; Kim, Young Dong; Yang, Byung Il; Kim, Kyung Hoon; Lee, Kang Sung; Kim, Eun Ja; Hwang, Byong Yong

    2016-06-01

    [Purpose] The aim of this study was to identify the contributions of balance to gait and motor function in chronic stroke. [Subjects and Methods] Twenty-three outpatients participated in a cross-sectional assessment. Gait ability was assessed using the functional ambulation category, self-paced 10-m walking speed, and fastest 10-m walking speed. Standing balance and trunk control measures included the Berg Balance Scale and the Trunk Impairment Scale. Univariate and multivariate regression analyses were performed. [Results] Balance was the best predictor of the FAC, self-paced walking speed, and fastest walking speed, accounting for 57% to 61% of the variances. Additionally, the total score of TIS was the only predictor of the motor function of the lower limbs and the dynamic balance of TIS was a predictor of the motor function of the upper limbs, accounting for 41% and 29% of the variance, respectively. [Conclusion] This study demonstrated the relative contribution of standing balance and trunk balance to gait ability and motor function. They show that balance has a high power of explanation of gait ability and that trunk balance is a determinant of motor function rather than gait ability.

  8. Transcranial direct current stimulation reverses neurophysiological and behavioural effects of focal inhibition of human pharyngeal motor cortex on swallowing.

    Science.gov (United States)

    Vasant, Dipesh H; Mistry, Satish; Michou, Emilia; Jefferson, Samantha; Rothwell, John C; Hamdy, Shaheen

    2014-02-15

    The human cortical swallowing system exhibits bilateral but functionally asymmetric representation in health and disease as evidenced by both focal cortical inhibition (pre-conditioning with 1 Hz repetitive transcranial magnetic stimulation; rTMS) and unilateral stroke, where disruption of the stronger (dominant) pharyngeal projection alters swallowing neurophysiology and behaviour. Moreover, excitatory neurostimulation protocols capable of reversing the disruptive effects of focal cortical inhibition have demonstrated therapeutic promise in post-stroke dysphagia when applied contralaterally. In healthy participants (n = 15, 8 males, mean age (±SEM) 35 ± 9 years), optimal parameters of transcranial direct current stimulation (tDCS) (anodal, 1.5 mA, 10 min) were applied contralaterally after 1 Hz rTMS pre-conditioning to the strongest pharyngeal projection. Swallowing neurophysiology was assessed in both hemispheres by intraluminal recordings of pharyngeal motor-evoked responses (PMEPs) to single-pulse TMS as a measure of cortical excitability. Swallowing behaviour was examined using a pressure-based reaction time protocol. Measurements were made before and for up to 60 min post intervention. Subjects were randomised to active or sham tDCS after 1 Hz rTMS on separate days and data were compared using repeated measures ANOVA. Active tDCS increased PMEPs bilaterally (F1,14 = 7.4, P = 0.017) reversing the inhibitory effects of 1 Hz rTMS in the pre-conditioned hemisphere (F1,14 = 10.1, P = 0.007). Active tDCS also enhanced swallowing behaviour, increasing the number of correctly timed challenge swallows compared to sham (F1,14 = 6.3, P = 0.025). Thus, tDCS to the contralateral pharyngeal motor cortex reverses the neurophysiological and behavioural effects of focal cortical inhibition on swallowing in healthy individuals and has therapeutic potential for dysphagia rehabilitation.

  9. Anodal transcranial direct current stimulation of the motor cortex induces opposite modulation of reciprocal inhibition in wrist extensor and flexor.

    Science.gov (United States)

    Lackmy-Vallée, Alexandra; Klomjai, Wanalee; Bussel, Bernard; Katz, Rose; Roche, Nicolas

    2014-09-15

    Transcranial direct current stimulation (tDCS) is used as a noninvasive tool to modulate brain excitability in humans. Recently, several studies have demonstrated that tDCS applied over the motor cortex also modulates spinal neural network excitability and therefore can be used to explore the corticospinal control acting on spinal neurons. Previously, we showed that reciprocal inhibition directed to wrist flexor motoneurons is enhanced during contralateral anodal tDCS, but it is likely that the corticospinal control acting on spinal networks controlling wrist flexors and extensors is not similar. The primary aim of the study was to explore the effects of anodal tDCS on reciprocal inhibition directed to wrist extensor motoneurons. To further examine the supraspinal control acting on the reciprocal inhibition between wrist flexors and extensors, we also explored the effects of the tDCS applied to the ipsilateral hand motor area. In healthy volunteers, we tested the effects induced by sham and anodal tDCS on reciprocal inhibition pathways innervating wrist muscles. Reciprocal inhibition directed from flexor to extensor muscles and the reverse situation, i.e., reciprocal inhibition, directed from extensors to flexors were studied in parallel with the H reflex technique. Our main finding was that contralateral anodal tDCS induces opposing effects on reciprocal inhibition: it decreases reciprocal inhibition directed from flexors to extensors, but it increases reciprocal inhibition directed from extensors to flexors. The functional result of these opposite effects on reciprocal inhibition seems to favor wrist extension excitability, suggesting an asymmetric descending control onto the interneurons that mediate reciprocal inhibition.

  10. Monitoring tooth profile faults in epicyclic gearboxes using synchronously averaged motor currents: Mathematical modeling and experimental validation

    Science.gov (United States)

    Ottewill, J. R.; Ruszczyk, A.; Broda, D.

    2017-02-01

    Time-varying transmission paths and inaccessibility can increase the difficulty in both acquiring and processing vibration signals for the purpose of monitoring epicyclic gearboxes. Recent work has shown that the synchronous signal averaging approach may be applied to measured motor currents in order to diagnose tooth faults in parallel shaft gearboxes. In this paper we further develop the approach, so that it may also be applied to monitor tooth faults in epicyclic gearboxes. A low-degree-of-freedom model of an epicyclic gearbox which incorporates the possibility of simulating tooth faults, as well as any subsequent tooth contact loss due to these faults, is introduced. By combining this model with a simple space-phasor model of an induction motor it is possible to show that, in theory, tooth faults in epicyclic gearboxes may be identified from motor currents. Applying the synchronous averaging approach to experimentally recorded motor currents and angular displacements recorded from a shaft mounted encoder, validate this finding. Comparison between experiments and theory highlight the influence of operating conditions, backlash and shaft couplings on the transient response excited in the currents by the tooth fault. The results obtained suggest that the method may be a viable alternative or complement to more traditional methods for monitoring gearboxes. However, general observations also indicate that further investigations into the sensitivity and robustness of the method would be beneficial.

  11. Adding effect of current displacement and magnetic circuit saturation in an asynchronous motor mathematical model

    Directory of Open Access Journals (Sweden)

    I.A. Tsodik

    2014-04-01

    Full Text Available A methodology of an asynchronous motor mathematical model synthesis is described. Experiments are suggested to be conducted in the following sequence. Geometrical models are first built in AutoCAD, then imported to Comsol Multiphysics, and further processed in Matlab with computation of coefficients and dependences applied in the asynchronous motor mathematical model.

  12. Structural and functional connectivity in healthy aging: Associations for cognition and motor behavior.

    Science.gov (United States)

    Hirsiger, Sarah; Koppelmans, Vincent; Mérillat, Susan; Liem, Franziskus; Erdeniz, Burak; Seidler, Rachael D; Jäncke, Lutz

    2016-03-01

    Age-related behavioral declines may be the result of deterioration of white matter tracts, affecting brain structural (SC) and functional connectivity (FC) during resting state. To date, it is not clear if the combination of SC and FC data could better predict cognitive/motor performance than each measure separately. We probed these relationships in the cingulum bundle, a major white matter pathway of the default mode network. We aimed to attain deeper knowledge about: (a) the relationship between age and the cingulum's SC and FC strength, (b) the association between SC and FC, and particularly (c) how the cingulum's SC and FC are related to cognitive/motor performance separately and combined. We examined these associations in a healthy and well-educated sample of 165 older participants (aged 64-85). SC and FC were acquired using probabilistic tractography to derive measures to capture white matter integrity within the cingulum bundle (fractional anisotropy, mean, axial and radial diffusivity) and a seed-based resting-state functional MRI correlation approach, respectively. Participants performed cognitive tests measuring processing speed, memory and executive functions, and motor tests measuring motor speed and grip force. Our data revealed that only SC but not resting state FC was significantly associated with age. Further, the cingulum's SC and FC showed no relation. Different relationships between cognitive/motor performance and SC/FC separately were found, but no additive effect of the combined analysis of cingulum's SC and FC for predicting cognitive/motor performance was apparent.

  13. Reduced Order Models of a Current Source Inverter Induction Motor Drive

    Directory of Open Access Journals (Sweden)

    Ibrahim K. Al-Abbas

    2009-01-01

    Full Text Available Problem Statement: The current source inverter induction motor (CSI-IM drive was widely used in various industries. The main disadvantage of this drive was nonlinearity and complexity. This work was done to develop a simple drive systems models. Approach: The MATLAB/SIMULINK software was used for system modeling. Three reduced models were developed by choosing specific frame, neglecting stator transients and ignoring stator equations. Results: The dynamic performance of the models was examined in open loop form for a step change in control variable (the input voltage as well as for step change in disturbance (mechanical load.Conclusion: The three models were equivalent in steady state. The error of these models in the transient response was less than 5 %, with the exception of the time performances of the transient model to step change of supply voltage. Recommendations: All three models were suggested to be used for designing torque control systems. The detailed and stator equation models were recommended to be used in speed control design.

  14. Robust sensorless control of BLDC Motor using second derivative function of the sum of terminal voltages

    Directory of Open Access Journals (Sweden)

    Boughaba Abdelali

    2013-01-01

    Full Text Available This paper proposes a new sensorless control method for the speed and position control of a BLDC Motor. This sensorless drive technique calculates the commutations instants (duration of commutation by deriving the sum of the terminal voltages of the motor (SigVi. Thus, it is possible to estimate the rotor position (and back EMF of the motor by only using measurements of the stator line currents and voltages. The implantation of these detectors is easy and cheap. This method is quite robust across variations in stator resistance due to changes in temperature or frequency. With this method the motor can be started without needing the initial position of the rotor. This proposed method is validated through extensive simulations at different speeds, and a very satisfactory performance has been achieved.

  15. Perilesional reorganization of motor function in stroke patients

    Institute of Scientific and Technical Information of China (English)

    Sung Ho Jang

    2010-01-01

    Perilesional reorganization is an important recovery mechanism for stroke patients because it yields good motor outcomes. However, perilesional reorganization remains poorly understood. The scientific basis for stroke rehabilitation can be established when detailed mechanisms of recovery are clarified. In addition, studies at the subcortical level remain in the early stages. Therefore, the present study suggested that additional investigations should focus on perilesional reorganization at the subcortical level, identifying the critical period for this mechanism and determining treatment strategies and modalities to facilitate development. The present study reviews literature focused on perilesional reorganization in stroke patients with regard to demonstration, clinical characteristics,and rehabilitative aspects, as well as previous studies of perilesional reorganization at cortical and subcortical levels.

  16. Enhanced functional connectivity between putamen and supplementary motor area in Parkinson's disease patients.

    Directory of Open Access Journals (Sweden)

    Rongjun Yu

    Full Text Available Parkinson's disease (PD is a surprisingly heterogeneous disorder with symptoms including resting tremor, bradykinesia and rigidity. PD has been associated with abnormal task related brain activation in sensory and motor regions as well as reward related network. Although corticostriatal skeletomotor circuit dysfunction is implicated in the neurobiology of Parkinson's disease, the functional connectivity within this circuit at the resting state is still unclear for PD. Here we utilized resting state functional magnetic resonance imaging to measure the functional connectivity of striatum and motor cortex in 19 patients with PD and 20 healthy controls. We found that the putamen, but not the caudate, exhibited enhanced connectivity with supplementary motor area (SMA, using either the putamen or the SMA as the "seed region". Enhanced SMA-amygdala functional connectivity was also found in the PD group, compared with normal controls. Our findings highlight the key role of hyper-connected putamen-SMC circuit in the pathophysiology of PD.

  17. Brain N-acetylaspartate levels correlate with motor function in metachromatic leukodystrophy

    DEFF Research Database (Denmark)

    í Dali, Christine; Hanson, Lars G.; Barton, N. W.

    2010-01-01

    in oligodendrocytes and is known as a marker for neuronal and axonal loss. NAA and other metabolite levels measured by proton magnetic resonance spectroscopy (MRS) correlate with performance of the brain in normal children. There is a need for sensitive measures of disease progression in patients with MLD to enable...... development of future reatments. Methods: A cross-section of 13 children with late infantile MLD were examined by proton MRS. Signals from NAA, total choline, and total creatine in the deep white matter were measured and correlated with the results of cognitive and motor function tests. Results: The NAA...... signal decreased as the disease process advanced. Motor function, measured by the Gross Motor Function Measure–88, varied from 13 (only head movement in the supine position) to 180 (able to walk) across the study cohort, demonstrating a wide range in functional status. Similarly, varied decreases were...

  18. Cognitive and motor function in long duration PARKIN PD

    Science.gov (United States)

    Alcalay, RN; Caccappolo, E; Mejia-Santana, H; Tang, M–X; Rosado, L; Orbe Reilly, M; Ruiz, D; Louis, ED; Comella, C; Nance, M; Bressman, S; Scott, WK; Tanner, C; Mickel, S; Waters, C; Fahn, S; Cote, L; Frucht, S; Ford, B; Rezak, M; Novak, K; Friedman, JH; Pfeiffer, R; Marsh, L; Hiner, B; Payami, H; Molho, E; Factor, SA; Nutt, J; Serrano, C; Arroyo, M; Ottman, R; Pauciulo, M; Nichols, W; Clark, LN; Marder, K

    2013-01-01

    Importance The long term cognitive outcome in PARKIN-PD patients is unknown. This data may be meaningful when counseling PARKIN-PD patients. Objective Among early-onset PD (EOPD) patients with long disease durations, we assessed cognitive and motor performances, comparing compound heterozygote/homozygote PARKIN carriers to non-carriers Design Cross sectional study Setting Seventeen movement disorders centers Participants Forty-four participants in the Consortium on Risk for Early-Onset PD (CORE-PD) with PD duration greater than median (>14 years), including PARKIN compound heterozygotes/homozygotes combined (n=21), and non-carriers (n=23). Main outcome measures Unified Parkinson’s Disease Rating Scale Part III (UPDRS), Clinical Dementia Rating (CDR) and neuropsychological performance. Linear regression models were applied to assess the association between PARKIN mutation status and cognitive domain scores and UPDRS. Models were adjusted for age, education, disease duration, language, and levodopa equivalent daily dose. Results Compound heterozygote/homozygote PARKIN mutation carriers had earlier AAO of PD (p<0.001) and were younger (p=0.004) at time of examination than non-carriers. They performed better on the MMSE (p=0.010) and were more likely to receive lower scores on the CDR (p=0.003). In multivariate analyses, PARKIN compound heterozygotes/homozygotes performed better on the UPDRS Part III (p=0.017), and on tests of attention (p=0.022), memory (p=0.025) and visuospatial (p=0.024) domains. Conclusions and Relevance Cross-sectional analyses demonstrate better cognitive and motor performance in compound heterozygote/homozygote PARKIN EOPD carriers than non-carriers with long disease duration, suggesting slower disease progression. Longitudinal follow up is required to confirm these findings. PMID:24190026

  19. Antihypertensive and Statin Medication Use and Motor Function in Community-Dwelling Older Adults

    Science.gov (United States)

    Perlman, Amichai; Shah, Raj C.; Bennett, David A.; Buchman, Aron S.; Matok, Ilan

    2015-01-01

    Objectives To investigate whether the use of antihypertensive and statin medication in very old adults is associated with the level of motor performance. Design Cross sectional study. Settings A community-based study recruited from over 40 residential facilities across the metropolitan Chicago area. Participants Community dwelling very old adults (n=1520; mean age 80.2; SD 7.7). Measurements Eleven motor performances were summarized using a composite motor score. All prescription and over the counter medications taken by participants were inspected and coded using the Medi-Span Data Base System. Demographic characteristics and medical history were obtained via detailed interview and medical exams. Results In multiple linear regression models, antihypertensive medications were associated with global motor score (β=−0.075, S.E. 0.011, p<0.001). Thus, motor function in an individual with antihypertensive medication, was on average, about 7.5% lower than an age, sex and education matched individual without antihypertensive medication. The number of antihypertensive medications which were being used had an additive effect, such that a reduction in the level of motor function was observed with each additional medication, and receiving three or more antihypertensive medications was associated with about a 15% reduction in the level of motor function. The association between antihypertensive medications and motor function was robust, and remained unchanged after adjusting for confounding by indication using several potentially confounding variables: smoking, hypertension, diabetes, stroke, congestive heart-failure, myocardial infarction, and intermittent claudication (β=−0.05, S.E. 0.015, p=0.001). In contrast, the use of statin medications was not related to motor function (unadjusted: β=0.003, S.E.=0.015, p=0.826; fully adjusted: β=0.018, S.E. 0.014, p=0.216). Conclusion The use of antihypertensive medications is associated with a lower level of motor function in

  20. Symmetric linear potential and imperfect Brownian ratchet in molecular motor function

    Institute of Scientific and Technical Information of China (English)

    Li Fang-Zhen; Hu Kuang-Hu; Su Wan-Fang; Chen Yi-Chen

    2005-01-01

    Biomolecular motors are tiny engines that transport materials at the microscopic level within biological cells. In recent years, Elston and Peskin et al have investigated the effect of the elastic properties of the tether that connects the motor to its cargo at the speed of the motor. In this paper we extend their work and present a tether in the form of symmetric linear potential. Our results show that when the driving mechanism is an imperfect Brownian ratchet, the average speed decreases as the stiffness of the tether increases in the limit of large motor diffusion coefficient, which is similar to the results of Elston and Peskin. However, a threshold for the stiffness of the tether connecting the motor to its cargo is found in our model. Only when the tether is stiffer than the threshold can the motor and its cargo function co-operatively, otherwise, the motor and its cargo depart from each other. This result is more realistic than that of the spring model of Elston and Peskin.

  1. Relationships between Motor and Executive Functions and the Effect of an Acute Coordinative Intervention on Executive Functions in Kindergartners.

    Science.gov (United States)

    Stein, Marion; Auerswald, Max; Ebersbach, Mirjam

    2017-01-01

    There is growing evidence indicating positive, causal effects of acute physical activity on cognitive performance of school children, adolescents, and adults. However, only a few studies examined these effects in kindergartners, even though correlational studies suggest moderate relationships between motor and cognitive functions in this age group. One aim of the present study was to examine the correlational relationships between motor and executive functions among 5- to 6-year-olds. Another aim was to test whether an acute coordinative intervention, which was adapted to the individual motor functions of the children, causally affected different executive functions (i.e., motor inhibition, cognitive inhibition, and shifting). Kindergartners (N = 102) were randomly assigned either to a coordinative intervention (20 min) or to a control condition (20 min). The coordination group performed five bimanual exercises (e.g., throwing/kicking balls onto targets with the right and left hand/foot), whereas the control group took part in five simple activities that hardly involved coordination skills (e.g., stamping). Children's motor functions were assessed with the Movement Assessment Battery for Children 2 (Petermann, 2009) in a pre-test (T1), 1 week before the intervention took place. Motor inhibition was assessed with the Simon says task (Carlson and Wang, 2007), inhibition and shifting were assessed with the Hearts and Flowers task (Davidson et al., 2006) in the pre-test and again in a post-test (T2) immediately after the interventions. Results revealed significant correlations between motor functions and executive functions (especially shifting) at T1. There was no overall effect of the intervention. However, explorative analyses indicated a three-way interaction, with the intervention leading to accuracy gains only in the motor inhibition task and only if it was tested directly after the intervention. As an unexpected effect, this result needs to be treated with

  2. Relationships between Motor and Executive Functions and the Effect of an Acute Coordinative Intervention on Executive Functions in Kindergartners

    Science.gov (United States)

    Stein, Marion; Auerswald, Max; Ebersbach, Mirjam

    2017-01-01

    There is growing evidence indicating positive, causal effects of acute physical activity on cognitive performance of school children, adolescents, and adults. However, only a few studies examined these effects in kindergartners, even though correlational studies suggest moderate relationships between motor and cognitive functions in this age group. One aim of the present study was to examine the correlational relationships between motor and executive functions among 5- to 6-year-olds. Another aim was to test whether an acute coordinative intervention, which was adapted to the individual motor functions of the children, causally affected different executive functions (i.e., motor inhibition, cognitive inhibition, and shifting). Kindergartners (N = 102) were randomly assigned either to a coordinative intervention (20 min) or to a control condition (20 min). The coordination group performed five bimanual exercises (e.g., throwing/kicking balls onto targets with the right and left hand/foot), whereas the control group took part in five simple activities that hardly involved coordination skills (e.g., stamping). Children’s motor functions were assessed with the Movement Assessment Battery for Children 2 (Petermann, 2009) in a pre-test (T1), 1 week before the intervention took place. Motor inhibition was assessed with the Simon says task (Carlson and Wang, 2007), inhibition and shifting were assessed with the Hearts and Flowers task (Davidson et al., 2006) in the pre-test and again in a post-test (T2) immediately after the interventions. Results revealed significant correlations between motor functions and executive functions (especially shifting) at T1. There was no overall effect of the intervention. However, explorative analyses indicated a three-way interaction, with the intervention leading to accuracy gains only in the motor inhibition task and only if it was tested directly after the intervention. As an unexpected effect, this result needs to be treated with

  3. Therapeutic effects of functional electrical stimulation on gait, motor recovery, and motor cortex in stroke survivors

    Directory of Open Access Journals (Sweden)

    C.V. Shendkar, MTech

    2015-06-01

    Conclusion: FES combined with physiotherapy induced better outcomes in the swing phase of the gait cycle, activation of the affected ankle dorsiflexor muscles and cortical function when compared with conventional physiotherapy alone.

  4. Functional connectivity of primary motor cortex is dependent on genetic burden in prodromal Huntington disease.

    Science.gov (United States)

    Koenig, Katherine A; Lowe, Mark J; Harrington, Deborah L; Lin, Jian; Durgerian, Sally; Mourany, Lyla; Paulsen, Jane S; Rao, Stephen M

    2014-09-01

    Subtle changes in motor function have been observed in individuals with prodromal Huntington disease (prHD), but the underlying neural mechanisms are not well understood nor is the cumulative effect of the disease (disease burden) on functional connectivity. The present study examined the resting-state functional magnetic resonance imaging (rs-fMRI) connectivity of the primary motor cortex (M1) in 16 gene-negative (NEG) controls and 48 gene-positive prHD participants with various levels of disease burden. The results showed that the strength of the left M1 connectivity with the ipsilateral M1 and somatosensory areas decreased as disease burden increased and correlated with motor symptoms. Weakened M1 connectivity within the motor areas was also associated with abnormalities in long-range connections that evolved with disease burden. In this study, M1 connectivity was decreased with visual centers (bilateral cuneus), but increased with a hub of the default mode network (DMN; posterior cingulate cortex). Changes in connectivity measures were associated with worse performance on measures of cognitive-motor functioning. Short- and long-range functional connectivity disturbances were also associated with volume loss in the basal ganglia, suggesting that weakened M1 connectivity is partly a manifestation of striatal atrophy. Altogether, the results indicate that the prodromal phase of HD is associated with abnormal interhemispheric interactions among motor areas and disturbances in the connectivity of M1 with visual centers and the DMN. These changes may, respectively, contribute to increased motor symptoms, visuomotor integration problems, and deficits in the executive control of movement as individuals approach a manifest diagnosis.

  5. Alteration of protein folding and degradation in motor neuron diseases : Implications and protective functions of small heat shock proteins

    NARCIS (Netherlands)

    Carra, Serena; Crippa, Valeria; Rusmini, Paola; Boncoraglio, Alessandra; Minoia, Melania; Giorgetti, Elisa; Kampinga, Harm H.; Poletti, Angelo

    2012-01-01

    Motor neuron diseases (MNDs) are neurodegenerative disorders that specifically affect the survival and function of upper and/or lower motor neurons. Since motor neurons are responsible for the control of voluntary muscular movement, MNDs are characterized by muscle spasticity, weakness and atrophy.

  6. The Contribution of Advanced Glycation End product (AGE) accumulation to the decline in motor function

    NARCIS (Netherlands)

    Drenth, Hans; Zuidema, Sytse; Bunt, Steven; Bautmans, Ivan; van der Schans, Cees; Hobbelen, Hans

    2016-01-01

    Diminishing motor function is commonly observed in the elderly population and is associated with a wide range of adverse health consequences. Advanced Glycation End products (AGE's) may contribute to age-related decline in the function of cells and tissues in normal ageing. Although the negative eff

  7. The Contribution of advanced glycation End product (AGE) accumulation to the decline in motor function

    NARCIS (Netherlands)

    Drenth, Hans; Zuidema, Sytse; Bunt, Steven; Bautmans, Ivan; Schans, Cees van der; Hobbelen, Hans

    2016-01-01

    Diminishing motor function is commonly observed in the elderly population and is associated with a wide range of adverse health consequences. Advanced Glycation End products (AGE’s) may contribute to age-related decline in the function of cells and tissues in normal ageing. Although the negative eff

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

    Science.gov (United States)

    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…

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

    OpenAIRE

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

    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 manipulat...

  10. Effect of therapist-based constraint-induced therapy at home on motor control, motor performance and daily function in children with cerebral palsy: a randomized controlled study.

    Science.gov (United States)

    Chen, Chia-ling; Kang, Lin-ju; Hong, Wei-Hsien; Chen, Fei-Chuan; Chen, Hsieh-Ching; Wu, Ching-yi

    2013-03-01

    To determine the effect of therapist-based constraint-induced therapy at home on motor performance, daily function and reaching control for children with cerebral palsy. A single-blinded, randomized controlled trial. Forty-seven children (23 boys; 24 girls) with unilateral cerebral palsy, aged 6-12 years, were randomized to constraint-induced therapy (n = 24) or traditional rehabilitation (n = 23). Constraint-induced therapy involved intensive functional training of the more affected arm while the less affected arm was restrained. Traditional rehabilitation involved functional unilateral and bilateral arm training. Both groups received individualized therapist-based interventions at home for 3.5-4 hours/day, two days a week for four weeks. Motor performance and daily function were measured by the Peabody Developmental Motor Scale, Second Edition and the Pediatric Motor Activity Log. Reaching control was assessed by the kinematics of reaction time, movement time, movement unit and peak velocity. There were larger effects in favour of constraint-induced therapy on motor performance, daily function, and some aspects of reaching control compared with traditional rehabilitation. Children receiving constraint-induced therapy demonstrated higher scores for Peabody Developmental Motor Scale, Second Edition - Grasping (pretest mean ± SD, 39.9 ± 3.1; posttest, 44.1 ± 2.8; P Motor Activity Log (pretest, 1.8 ± 0.3; posttest, 2.5 ± 0.3; P control of reaching in children with unilateral cerebral palsy than traditional rehabilitation.

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

    Science.gov (United States)

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

    2003-05-01

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

  12. Research progress of motor function assessments and their clinical applications in Duchenne muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Wei SHI

    2015-07-01

    Full Text Available Duchenne muscular dystrophy (DMD, clinically featured as progressive skeletal muscle atrophy with gradual loss of muscle strength and activity abilities, is the most common genetic muscular disease in children throughout the world. The core and continuous characteristic of DMD is motor dysfunction. Motor function assessments of DMD are now focusing on muscle strength, walking ability, range of motion and ability of activities, still without unified standards. Confirming the comprehensive, scientific, reasonable and accurate evaluation tools for DMD assessment is the premise of research in motor developmental rules of DMD, which will help to better understand the motor progress of DMD and to supply evidences for choosing treatment methods, confirming timing of intervention, assessing effect of treatments and designing rehabilitation plans. DOI: 10.3969/j.issn.1672-6731.2015.06.002

  13. 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.)

  14. Longitudinal Changes of Resting-State Functional Connectivity during Motor Recovery after Stroke

    Science.gov (United States)

    Park, Chang-hyun; Chang, Won Hyuk; Ohn, Suk Hoon; Kim, Sung Tae; Bang, Oh Young; Pascual-Leone, Alvaro; Kim, Yun-Hee

    2013-01-01

    Background and Purpose Functional magnetic resonance imaging (fMRI) studies could provide crucial information on the neural mechanisms of motor recovery in stroke patients. Resting-state fMRI is applicable to stroke patients who are not capable of proper performance of the motor task. In this study, we explored neural correlates of motor recovery in stroke patients by investigating longitudinal changes in resting-state functional connectivity of the ipsilesional primary motor cortex (M1). Methods A longitudinal observational study using repeated fMRI experiments was conducted in 12 patients with stroke. Resting-state fMRI data were acquired four times over a period of 6 months. Patients participated in the first session of fMRI shortly after onset, and thereafter in subsequent sessions at 1, 3, and 6 months after onset. Resting-state functional connectivity of the ipsilesional M1 was assessed and compared with that of healthy subjects. Results Compared with healthy subjects, patients demonstrated higher functional connectivity with the ipsilesional frontal and parietal cortices, bilateral thalamus, and cerebellum. Instead, functional connectivity with the contralesional M1 and occipital cortex were decreased in stroke patients. Functional connectivity between the ipsilesional and contralesional M1 showed the most asymmetry at 1 month after onset to the ipsilesional side. Functional connectivity of the ipsilesional M1 with the contralesional thalamus, supplementary motor area, and middle frontal gyrus at onset was positively correlated with motor recovery at 6 months after stroke. Conclusions Resting-state fMRI elicited distinctive but comparable results with previous task-based fMRI, presenting complementary and practical values for use in the study of stroke patients. PMID:21441147

  15. Effect of Dorsiflexor Muscle Strengthening Using Russian Currents on Balance and Function in Elderly

    Directory of Open Access Journals (Sweden)

    Sonia Singh

    2013-04-01

    Full Text Available Balance difficulties are one of the major causes of altered mobility and functional decline in the elderly. Over the past 20 years, a considerable amount of research has been conducted to determine the relationship between balance control and motor or sensory system function in order to understand the causes of falling and to create effective strategies to prevent falls in elderly people The present study was done to determine the effectiveness of dorsiflexor muscle strengthening using Russian stimulation to improve balance and function in elderly. Motor component of balance was evaluated using two tests, i.e., mPOMA and Functional reach test whereas sensory component of balance was measured using mCTSIB and reaction time. Functional performance was typically assessed by Functional gait assessment test, functional ability in performing ADL (like bathing, toileting and IADL (like travelling, shopping tasks. Results of the study suggested that balance and functional status of the elderly improved significantly after eight weeks of dorsiflexor strengthening using Russian currents.

  16. 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.

  17. Stimulus electrodiagnosis and motor and functional evaluations during ulnar nerve recovery

    Science.gov (United States)

    Fernandes, Luciane F. R. M.; Oliveira, Nuno M. L.; Pelet, Danyelle C. S.; Cunha, Agnes F. S.; Grecco, Marco A. S.; Souza, Luciane A. P. S.

    2016-01-01

    BACKGROUND: Distal ulnar nerve injury leads to impairment of hand function due to motor and sensorial changes. Stimulus electrodiagnosis (SE) is a method of assessing and monitoring the development of this type of injury. OBJECTIVE: To identify the most sensitive electrodiagnostic parameters to evaluate ulnar nerve recovery and to correlate these parameters (Rheobase, Chronaxie, and Accommodation) with motor function evaluations. METHOD: A prospective cohort study of ten patients submitted to ulnar neurorrhaphy and evaluated using electrodiagnosis and motor assessment at two moments of neural recovery. A functional evaluation using the DASH questionnaire (Disability of the Arm, Shoulder, and Hand) was conducted at the end to establish the functional status of the upper limb. RESULTS: There was significant reduction only in the Chronaxie values in relation to time of injury and side (with and without lesion), as well as significant correlation of Chronaxie with the motor domain score. CONCLUSION: Chronaxie was the most sensitive SE parameter for detecting differences in neuromuscular responses during the ulnar nerve recovery process and it was the only parameter correlated with the motor assessment. PMID:26786072

  18. 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.)

  19. Stimulus electrodiagnosis and motor and functional evaluations during ulnar nerve recovery

    Directory of Open Access Journals (Sweden)

    Luciane F. R. M. Fernandes

    2016-01-01

    Full Text Available BACKGROUND: Distal ulnar nerve injury leads to impairment of hand function due to motor and sensorial changes. Stimulus electrodiagnosis (SE is a method of assessing and monitoring the development of this type of injury. OBJECTIVE: To identify the most sensitive electrodiagnostic parameters to evaluate ulnar nerve recovery and to correlate these parameters (Rheobase, Chronaxie, and Accommodation with motor function evaluations. METHOD: A prospective cohort study of ten patients submitted to ulnar neurorrhaphy and evaluated using electrodiagnosis and motor assessment at two moments of neural recovery. A functional evaluation using the DASH questionnaire (Disability of the Arm, Shoulder, and Hand was conducted at the end to establish the functional status of the upper limb. RESULTS: There was significant reduction only in the Chronaxie values in relation to time of injury and side (with and without lesion, as well as significant correlation of Chronaxie with the motor domain score. CONCLUSION: Chronaxie was the most sensitive SE parameter for detecting differences in neuromuscular responses during the ulnar nerve recovery process and it was the only parameter correlated with the motor assessment.

  20. Motor power control circuit for ac induction motors

    Science.gov (United States)

    Nola, F. J. (Inventor)

    1983-01-01

    A motor power control of the type which functions by controlling the power factor wherein one of the parameters of power factor current on time is determined by the on time of a triac through which current is supplied to the motor. By means of a positive feedback circuit, a wider range of control is effected.

  1. Recognition of Thermal Images of Direct Current Motor with Application of Area Perimeter Vector and Bayes Classifier

    Directory of Open Access Journals (Sweden)

    Glowacz Adam

    2015-06-01

    Full Text Available Infrared thermography can measure the temperature of a surface remotely. In this article authors present a diagnostic method of incipient fault detection. The proposed approach is based on pattern recognition. It uses monochrome thermal images of the rotor with the application of an area perimeter vector and a Bayes classifier. The investigations have been carried out for direct current motor without faults and motor with shorted rotor coils. The measurements were performed in the laboratory. The efficiency of recognition using the area perimeter vector and the Bayes classifier was 100 %. The investigations show that the method based on recognition of thermal images can be profitable for engineers. The proposed method can be applied in mining, metallurgy, fuel industry and in factories where electrical motors are used.

  2. Assignment Confidence in Localization of the Hand Motor Cortex: Comparison of Structural Imaging With Functional MRI.

    Science.gov (United States)

    Sahin, Neslin; Mohan, Suyash; Maralani, Pejman J; Duddukuri, Srikalyan; O'Rourke, Donald M; Melhem, Elias R; Wolf, Ronald L

    2016-12-01

    The purpose of this study was to assign confidence levels to structural MRI and functional MRI (fMRI) for localization of the primary motor cortex. Ninety-one fMRI studies with at least one motor task (178 hemispheres) were identified. Three anatomic assessments were used to localize the primary motor cortex: relation between the superior frontal sulcus and precentral sulcus; cortical thickness; and configuration of the precentral knob. In 105 hemispheres, interreader agreement was assessed for two investigators with different experience levels. Confidence ratings from 0 to 5 (0, no confidence; 5, 100% confidence) were assigned for fMRI and each anatomic localization method. Cortical thickness had the highest confidence rating (mean, 4.90 ± 0.47 [SD]) with only one failure. The relation between the superior frontal sulcus and precentral sulcus had the lowest confidence rating (4.33 ± 0.91) with three failures. The greatest statistical significance was observed for the cortical thickness and superior frontal sulcus-precentral sulcus methods (post hoc Bonferroni test, p Confidence rating scores were significantly higher for the cortical thickness sign than for fMRI results (4.72 ± 0.54) for a single motor task (post hoc Bonferroni test, p = 0.006); however, the mean confidence rating for fMRI improved to 4.87 ± 0.36 when additional motor tasks were performed. Interreader differences were least for the cortical thickness sign (paired t test, t = 4.25, p confidence regarding localization of the primary motor cortex; however, localization of motor function is more specific when combined with fMRI findings. Multiple techniques can be used to increase confidence in identifying the hand motor cortex.

  3. Personal experience with narrated events modulates functional connectivity within visual and motor systems during story comprehension.

    Science.gov (United States)

    Chow, Ho Ming; Mar, Raymond A; Xu, Yisheng; Liu, Siyuan; Wagage, Suraji; Braun, Allen R

    2015-04-01

    Past experience of everyday life activities, which forms the basis of our knowledge about the world, greatly affects how we understand stories. Yet, little is known about how this influence is instantiated in the human brain. Here, we used functional magnetic resonance imaging to investigate how past experience facilitates functional connectivity during the comprehension of stories rich in perceptual and motor details. We found that comprehenders' past experience with the scenes and actions described in the narratives selectively modulated functional connectivity between lower- and higher-level areas within the neural systems for visual and motor processing, respectively. These intramodal interactions may play an important role in integrating personal knowledge about a narrated situation with an evolving discourse representation. This study provides empirical evidence consistent with the idea that regions related to visual and motor processing are involved in the reenactment of experience as proposed by theories of embodied cognition.

  4. Pseudocataplexy and transient functional paralysis: a spectrum of psychogenic motor disorder.

    Science.gov (United States)

    Shankar, Rohit; Jalihal, Virupakshi; Walker, Matthew; Zeman, Adam

    2010-01-01

    The authors describe and discuss a syndrome of transient psychogenic weakness usually mistaken for cataplexy but which has a close association with a depressive mental state. Four patients were referred to the authors with suspected neurological causes of transient weakness, including cataplexy in three cases, for whom the eventual diagnosis was of a functional or psychogenic motor disorder, related in most cases to depression. This variety of transient functional weakness is related to conditions such as nonepileptic attack disorder, persistent functional weakness, catatonia, and depressive motor retardation. These cases point to the existence of a syndrome of transient motor weakness which resembles cataplexy and has features in common with other forms of mood induced psychogenic weakness such as psychomotor retardation and catatonia. Psychogenic "pseudocataplexy" is a diagnostic consideration in patients with atypical cataplexy, especially in the context of mood disturbance. Despite its close resemblance to cataplexy, pseudocataplexy has a different pathogenesis and requires a different approach to management.

  5. Differential effects of primary motor cortex and cerebellar transcranial direct current stimulation on motor learning in healthy individuals: A randomized double-blind sham-controlled study.

    Science.gov (United States)

    Ehsani, F; Bakhtiary, A H; Jaberzadeh, S; Talimkhani, A; Hajihasani, A

    2016-11-01

    The purpose of study was to compare the effect of primary motor cortex (M1) and cerebellar anodal transcranial direct current stimulation (a-tDCS) on online and offline motor learning in healthy individuals. Fifty-nine healthy volunteers were randomly divided into three groups (n=20 in two experimental groups and n=19 in sham-control group). One experimental group received M1a-tDCSand another received cerebellar a-tDCS. The main outcome measure were response time (RT) and number of errors during serial response time test (SRTT) which were assessed prior, 35min and 48h after the interventions. Reduction of response time (RT) and error numbers at last block of the test compared to the first block was considered online learning. Comparison of assessments during retention tests was considered as short-term and long-term offline learning. Online RT reduction was not different among groups (P>0.05), while online error reduction was significantly greater in cerebellar a-tDCS than sham-control group (Plearning as compared to sham tDCS (Pgroup (Plearning and M1a-tDCS has more effect on short-term offline learning, both M1 and cerebellar a-tDCS can be used as a boosting technique for improvement of offline motor learning in healthy individuals. Crown Copyright © 2016. Published by Elsevier Ireland Ltd. All rights reserved.

  6. Potentiation of motor sub-networks for motor control but not working memory: Interaction of dACC and SMA revealed by resting-state directed functional connectivity.

    Science.gov (United States)

    Diwadkar, Vaibhav A; Asemi, Avisa; Burgess, Ashley; Chowdury, Asadur; Bressler, Steven L

    2017-01-01

    The dorsal Anterior Cingulate Cortex (dACC) and the Supplementary Motor Area (SMA) are known to interact during motor coordination behavior. We previously discovered that the directional influences underlying this interaction in a visuo-motor coordination task are asymmetric, with the dACC→SMA influence being significantly greater than that in the reverse direction. To assess the specificity of this effect, here we undertook an analysis of the interaction between dACC and SMA in two distinct contexts. In addition to the motor coordination task, we also assessed these effects during a (n-back) working memory task. We applied directed functional connectivity analysis to these two task paradigms, and also to the rest condition of each paradigm, in which rest blocks were interspersed with task blocks. We report here that the previously known asymmetric interaction between dACC and SMA, with dACC→SMA dominating, was significantly larger in the motor coordination task than the memory task. Moreover the asymmetry between dACC and SMA was reversed during the rest condition of the motor coordination task, but not of the working memory task. In sum, the dACC→SMA influence was significantly greater in the motor task than the memory task condition, and the SMA→dACC influence was significantly greater in the motor rest than the memory rest condition. We interpret these results as suggesting that the potentiation of motor sub-networks during the motor rest condition supports the motor control of SMA by dACC during the active motor task condition.

  7. Potentiation of motor sub-networks for motor control but not working memory: Interaction of dACC and SMA revealed by resting-state directed functional connectivity

    Science.gov (United States)

    Diwadkar, Vaibhav A.; Asemi, Avisa; Burgess, Ashley; Chowdury, Asadur; Bressler, Steven L.

    2017-01-01

    The dorsal Anterior Cingulate Cortex (dACC) and the Supplementary Motor Area (SMA) are known to interact during motor coordination behavior. We previously discovered that the directional influences underlying this interaction in a visuo-motor coordination task are asymmetric, with the dACC→SMA influence being significantly greater than that in the reverse direction. To assess the specificity of this effect, here we undertook an analysis of the interaction between dACC and SMA in two distinct contexts. In addition to the motor coordination task, we also assessed these effects during a (n-back) working memory task. We applied directed functional connectivity analysis to these two task paradigms, and also to the rest condition of each paradigm, in which rest blocks were interspersed with task blocks. We report here that the previously known asymmetric interaction between dACC and SMA, with dACC→SMA dominating, was significantly larger in the motor coordination task than the memory task. Moreover the asymmetry between dACC and SMA was reversed during the rest condition of the motor coordination task, but not of the working memory task. In sum, the dACC→SMA influence was significantly greater in the motor task than the memory task condition, and the SMA→dACC influence was significantly greater in the motor rest than the memory rest condition. We interpret these results as suggesting that the potentiation of motor sub-networks during the motor rest condition supports the motor control of SMA by dACC during the active motor task condition. PMID:28278267

  8. Increased resting state connectivity between ipsilesional motor cortex and contralesional premotor cortex after transcranial direct current stimulation with physical therapy.

    Science.gov (United States)

    Chen, Joyce L; Schlaug, Gottfried

    2016-03-16

    Non-invasive stimulation of the brain using transcranial direct current stimulation (tDCS) during motor rehabilitation can improve the recovery of movements in individuals with stroke. However, the neural substrates that underlie the clinical improvements are not well understood. In this proof-of-principle open-label pilot study, five individuals with stroke received 10 sessions of tDCS while undergoing usual care physical/occupational therapy for the arm and hand. Motor impairment as indexed by the Upper Extremity Fugl Meyer assessment was significantly reduced after the intervention. Resting state fMRI connectivity increased between ipsilesional motor cortex and contralesional premotor cortex after the intervention. These findings provide preliminary evidence that the neural underpinnings of tDCS coupled with rehabilitation exercises, may be mediated by interactions between motor and premotor cortex. The latter, of which has been shown to play an important role in the recovery of movements post-stroke. Our data suggest premotor cortex could be tested as a target region for non-invasive brain-stimulation to enhance connectivity between regions that might be beneficial for stroke motor recovery.

  9. Increased resting state connectivity between ipsilesional motor cortex and contralesional premotor cortex after transcranial direct current stimulation with physical therapy

    Science.gov (United States)

    Chen, Joyce L; Schlaug, Gottfried

    2016-01-01

    Non-invasive stimulation of the brain using transcranial direct current stimulation (tDCS) during motor rehabilitation can improve the recovery of movements in individuals with stroke. However, the neural substrates that underlie the clinical improvements are not well understood. In this proof-of-principle open-label pilot study, five individuals with stroke received 10 sessions of tDCS while undergoing usual care physical/occupational therapy for the arm and hand. Motor impairment as indexed by the Upper Extremity Fugl Meyer assessment was significantly reduced after the intervention. Resting state fMRI connectivity increased between ipsilesional motor cortex and contralesional premotor cortex after the intervention. These findings provide preliminary evidence that the neural underpinnings of tDCS coupled with rehabilitation exercises, may be mediated by interactions between motor and premotor cortex. The latter, of which has been shown to play an important role in the recovery of movements post-stroke. Our data suggest premotor cortex could be tested as a target region for non-invasive brain-stimulation to enhance connectivity between regions that might be beneficial for stroke motor recovery. PMID:26980052

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  11. Mesenchymal stem cell transplantation ameliorates motor function deterioration of spinocerebellar ataxia by rescuing cerebellar Purkinje cells

    Directory of Open Access Journals (Sweden)

    Ma Wei-Hsien

    2011-08-01

    Full Text Available Abstract Background Spinocerebellar ataxia (SCA refers to a disease entity in which polyglutamine aggregates are over-produced in Purkinje cells (PCs of the cerebellum as well as other neurons in the central nervous system, and the formation of intracellular polyglutamine aggregates result in the loss of neurons as well as deterioration of motor functions. So far there is no effective neuroprotective treatment for this debilitating disease although numerous efforts have been made. Mesenchymal stem cells (MSCs possess multi-lineage differentiation potentials as well as immuno-modulatory properties, and are theoretically good candidates for SCA treatment. The purpose of this study is to investigate whether transplantation of human MSCs (hMSCs can rescue cerebellar PCs and ameliorate motor function deterioration in SCA in a pre-clinical animal model. Method Transgenic mice bearing poly-glutamine mutation in ataxin-2 gene (C57BL/6J SCA2 transgenic mice were serially transplanted with hMSCs intravenously or intracranially before and after the onset of motor function loss. Motor function of mice was evaluated by an accelerating protocol of rotarod test every 8 weeks. Immunohistochemical stain of whole brain sections was adopted to demonstrate the neuroprotective effect of hMSC transplantation on cerebellar PCs and engraftment of hMSCs into mice brain. Results Intravenous transplantation of hMSCs effectively improved rotarod performance of SCA2 transgenic mice and delayed the onset of motor function deterioration; while intracranial transplantation failed to achieve such neuroprotective effect. Immunohistochemistry revealed that intravenous transplantation was more effective in the preservation of the survival of cerebellar PCs and engraftment of hMSCs than intracranial injection, which was compatible to rotarod performance of transplanted mice. Conclusion Intravenous transplantation of hMSCs can indeed delay the onset as well as improve the motor

  12. Functional organization of motor cortex of adult macaque monkeys is altered by sensory loss in infancy.

    Science.gov (United States)

    Qi, Hui-Xin; Jain, Neeraj; Collins, Christine E; Lyon, David C; Kaas, Jon H

    2010-02-16

    When somatosensory cortex (S1) is deprived of some of its inputs after section of ascending afferents in the dorsal columns of the spinal cord, it reorganizes to overrepresent the surviving inputs. As somatosensory cortex provides guiding sensory information to motor cortex, such sensory loss and representational reorganization could affect the development of the motor map in primary motor cortex (M1), especially if the sensory loss occurs early in development. To address this possibility, the dorsal columns of the spinal cord were sectioned between cervical levels (C3-5) 3-12 days after birth in five macaque monkeys. After 3-5 years of maturation (young adults), we determined how movements were represented in M1 contralateral to the lesion by using microelectrodes to electrically stimulate sites in M1 to evoke movements. Although the details of the motor maps in these five monkeys varied, the forelimb motor maps were abnormal. The representations of digit movements were reduced and abnormally arranged. Current levels for evoking movements from the forelimb region of M1 were in the normal range, but the lowest mean stimulation thresholds were for wrist or elbow instead of digit movements. Incomplete lesions and bilateral lesions produced fewer abnormalities. The results suggest that the development of normal motor cortex maps in M1 depends on sensory feedback from somatosensory maps.

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

    OpenAIRE

    Carmel, Jason B; John eMartin

    2014-01-01

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

  14. The Role of Brain Aging in Cognition and Motor Function

    NARCIS (Netherlands)

    Y.Y. Hoogendam (Jory)

    2014-01-01

    markdownabstract__Abstract__ Aging of the population is accompanied by many challenges, such as the maintenance of health and quality of life during older age. An important aspect of living longer is that old age is related to disease and loss of functions. The loss of brain functions poses a large

  15. Innovative motor insurance schemes: A review of current practices and emerging challenges.

    Science.gov (United States)

    Tselentis, Dimitrios I; Yannis, George; Vlahogianni, Eleni I

    2017-01-01

    The objective of this paper is to provide a review of the most popular and often implemented methodologies related to Usage-based motor insurance (UBI). UBI schemes, such as Pay-as-you-drive (PAYD) and Pay-how-you-drive (PHYD), are a new innovative concept that has recently started to be commercialized around the world. The main idea is that instead of a fixed price, drivers have to pay a premium based on their travel and driving behaviour. Despite the fact that it has been implemented only for a few years, it appears to be a very promising practice with a significant potential impact on traffic safety as well as on traffic congestion mitigation and pollution emissions reduction. To this end, the existing literature on UBI schemes is reviewed and research gaps are identified Findings show that there is a multiplicity and diversity of several research studies accumulated in modern literature examining the correlation between PAYD (based on driver's travel behaviour and exposure) and PHYD (based on driving behaviour) schemes and crash risk in order to determine crash risk. Moreover, there is evidence that UBI implementation would eliminate the cross-subsidies phenomenon, which implies less insurance costs for less risky and exposed drivers. It would also provide a strong motivation for drivers to improve their driving behaviour, differentiate their travel behaviour and reduce their degree of exposure by receiving feedback and monitoring their driving preferences and performance, which would result in crash risk reduction both totally and individually. The paper finally discussed the current and emerging challenges on this research field.

  16. Reliability of a Shuttle Run Test for Children with Cerebral Palsy Who Are Classified at Gross Motor Function Classification System Level III

    Science.gov (United States)

    Verschuren, Olaf; Bosma, Liesbeth; Takken, Tim

    2011-01-01

    For children and adolescents with cerebral palsy (CP) classified as Gross Motor Function Classification System (GMFCS) level III there is no running-based field test available to assess their cardiorespiratory fitness. The current study investigated whether a shuttle run test can be reliably (test-retest) performed in a group of children with…

  17. Morphology and motor function of the gastrointestinal tract examined with endosonography

    Institute of Scientific and Technical Information of China (English)

    Svein Odegaard; Lars Birger Nesje; Dag Arne Lihaug Hoff; Odd Helge Gilja; Hans Gregersen

    2006-01-01

    Endosonography is a useful tool for studying the morphology and motor function of the gastrointestinal tract. Intraluminal ultrasonography is the common denomination of ultrasound examinations using intracorporal transducers which are inserted into the GI tract. Thus, the visceral wall and adjacent structures can be imaged in detail. This review describes the usefulness of endosonography in gastroenterology, in particular with respect to studies of the biomechanical and motor function of the gastrointestinal tract. New techniques such as 3-D EUS, elastography and strain rate imaging are discussed.

  18. Improving gross motor function and postural control with hippotherapy in children with Down syndrome: case reports.

    Science.gov (United States)

    Champagne, Danielle; Dugas, Claude

    2010-11-01

    The purpose of this case report is to describe the impact of an 11-week hippotherapy program on the gross motor functions of two children (respectively 28 and 37 months old) diagnosed with Down syndrome. Hippotherapy is a strategy that uses the horse's motion to stimulate and enhance muscle contraction and postural control. The children were assessed by the Gross Motor Function Measure (GMFM) and accelerometry. The results indicate that both children improved on many dimensions of the GMFM. Power spectral analysis of the acceleration signals showed improvement in postural control of either the head or trunk, because the children adopted two different adaptative strategies to perturbation induced by the moving horse.

  19. 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

    Purpose 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). Methods 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. Results 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). Conclusion 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. PMID:28223840

  20. Measurement of Gastrointestinal and Colonic Motor Functions in Humans and Animals

    OpenAIRE

    Camilleri, Michael; Linden, David R

    2016-01-01

    Accurately measuring the complex motor behaviors of the gastrointestinal tract has tremendous value for the understanding, diagnosis and treatment of digestive diseases. This review synthesizes the literature regarding current tests that are used in both humans and animals. There remains further opportunity to enhance such tests, especially when such tests are able to provide value in both the preclinical and the clinical settings.

  1. Effect of cerebrolysin on gross motor function of children with cerebral palsy: a clinical trial.

    Science.gov (United States)

    Nasiri, Jafar; Safavifar, Faezeh

    2017-01-10

    Gross motor dysfunction is considered as the most challenging problem in cerebral palsy (CP). It is proven that improvement of gross motor function could reduce CP-related disabilities and provide better quality of life in this group of patients. Therefore, the aim of this trial is to evaluate the effectiveness of cerebrolysin (CBL) on gross motor function of children with CP who are undergoing treatment. In this clinical trial study, paediatric patients aged 18-75 months with spastic diplegic or quadriplegic cerebral palsy, who were under rehabilitation therapy, were selected and randomly allocated in control and CBL groups. Patients in CBL group underwent treatment with standard rehabilitation therapy plus CBL. The latter was administrated intramuscularly as a single daily dose of 0.1 cc/kg for 10 days and then continued weekly for 4 months. Gross motor function of participants in the two studied groups, before and after trial, was evaluated and compared using the validated Persian version of gross motor function classification system-expanded and revised (GMFCS-E&R). During this trial, 108 patients with CP were evaluated for eligibility. From these, 50 patients were enrolled and randomly allocated in the CBL and control groups. Four months after trial, the mean level of GMFCS decreased significantly in the two groups (P < 0.05). However, it was significantly lower in the CBL group than in the control group (2.1 vs. 3.16, P < 0.05). The results of this trial indicated that CBL could improve gross motor function in patients with CP. This finding is consistent with neurotrophic and neuroprotective effects of CBL, which have been reported in various clinical trials in other neurological disorders. Further studies are recommended to establish the value of continued neuroprotection and to determine the pharmacokinetics/dynamics of CBL in this group of patients.

  2. Mental representation and mental practice: experimental investigation on the functional links between motor memory and motor imagery.

    Science.gov (United States)

    Frank, Cornelia; Land, William M; Popp, Carmen; Schack, Thomas

    2014-01-01

    Recent research on mental representation of complex action has revealed distinct differences in the structure of representational frameworks between experts and novices. More recently, research on the development of mental representation structure has elicited functional changes in novices' representations as a result of practice. However, research investigating if and how mental practice adds to this adaptation process is lacking. In the present study, we examined the influence of mental practice (i.e., motor imagery rehearsal) on both putting performance and the development of one's representation of the golf putt during early skill acquisition. Novice golfers (N = 52) practiced the task of golf putting under one of four different practice conditions: mental, physical, mental-physical combined, and no practice. Participants were tested prior to and after a practice phase, as well as after a three day retention interval. Mental representation structures of the putt were measured, using the structural dimensional analysis of mental representation. This method provides psychometric data on the distances and groupings of basic action concepts in long-term memory. Additionally, putting accuracy and putting consistency were measured using two-dimensional error scores of each putt. Findings revealed significant performance improvements over the course of practice together with functional adaptations in mental representation structure. Interestingly, after three days of practice, the mental representations of participants who incorporated mental practice into their practice regime displayed representation structures that were more similar to a functional structure than did participants who did not incorporate mental practice. The findings of the present study suggest that mental practice promotes the cognitive adaptation process during motor learning, leading to more elaborate representations than physical practice only.

  3. Evaluation of preoperative high magnetic field motor functional MRI (3 Tesla) in glioma patients by navigated electrocortical stimulation and postoperative outcome

    National Research Council Canada - National Science Library

    Roessler, K; Donat, M; Lanzenberger, R; Novak, K; Geissler, A; Gartus, A; Tahamtan, A R; Milakara, D; Czech, T; Barth, M; Knosp, E; Beisteiner, R

    2005-01-01

    The validity of 3 Tesla motor functional magnetic resonance imaging (fMRI) in patients with gliomas involving the primary motor cortex was investigated by intraoperative navigated motor cortex stimulation (MCS...

  4. Early onset of forced impaired forelimb use causes recovery of forelimb skilled motor function but no effect on gross sensory-motor function after capsular hemorrhage in rats.

    Science.gov (United States)

    Ishida, Akimasa; Tamakoshi, Keigo; Hamakawa, Michiru; Shimada, Haruka; Nakashima, Hiroki; Masuda, Tadashi; Hida, Hideki; Ishida, Kazuto

    2011-11-20

    Intensive use of the impaired forelimb promotes behavioral recovery and induces plastic changes of the central nervous system after stroke. However, the optimal onset of intensive use treatment after stroke is controversial. In this study, we investigated whether early forced impaired limb use (FLU) initiated 24h after intracerebral hemorrhage (ICH) of the internal capsule affected behavioral recovery and histological damage. Rats were subjected to ICH via low-dose collagenase infusion or sham stroke. One day after surgery, the ipsilateral forelimbs of half of the ICH and sham rats were casted for a week to induce the use of their contralateral forelimbs. Behavioral assessments were performed on days 10-12 and 26-28 after the surgery and followed by histological assessments. Improvements in skilled reaching and coordinated stepping function were found in the FLU-treated group in comparison with the untreated group after ICH. Additionally, FLU-treated ICH animals showed more normal and precise reaching and stepping movements as compared with ICH control animals. In contrast, FLU did not have a significant impact on gross sensory-motor functions such as the motor deficit score, contact placing response and spontaneous usage of the impaired paw. The volume of tissue lost and the number of spared corticospinal neurons in lesioned motor cortex were not affected by early FLU after ICH. These findings demonstrate the efficacy of early focused use of an impaired limb after internal capsule hemorrhage.

  5. Reorganizing the intrinsic functional architecture of the human primary motor cortex during rest with non-invasive cortical stimulation.

    Directory of Open Access Journals (Sweden)

    Rafael Polanía

    Full Text Available The primary motor cortex (M1 is the main effector structure implicated in the generation of voluntary movements and is directly involved in motor learning. The intrinsic horizontal neuronal connections of M1 exhibit short-term and long-term plasticity, which is a strong substrate for learning-related map reorganization. Transcranial direct current stimulation (tDCS applied for few minutes over M1 has been shown to induce relatively long-lasting plastic alterations and to modulate motor performance. Here we test the hypothesis that the relatively long-lasting synaptic modification induced by tDCS over M1 results in the alteration of associations among populations of M1 neurons which may be reflected in changes of its functional architecture. fMRI resting-state datasets were acquired immediately before and after 10 minutes of tDCS during rest, with the anode/cathode placed over the left M1. For each functional dataset, grey-matter voxels belonging to Brodmann area 4 (BA4 were labelled and afterwards BA4 voxel-based synchronization matrices were calculated and thresholded to construct undirected graphs. Nodal network parameters which characterize the architecture of functional networks (connectivity degree, clustering coefficient and characteristic path-length were computed, transformed to volume maps and compared before and after stimulation. At the dorsolateral-BA4 region cathodal tDCS boosted local connectedness, while anodal-tDCS enhanced long distance functional communication within M1. Additionally, the more efficient the functional architecture of M1 was at baseline, the more efficient the tDCS-induced functional modulations were. In summary, we show here that it is possible to non-invasively reorganize the intrinsic functional architecture of M1, and to image such alterations.

  6. Effects of functional electrical therapy on upper extremity functional motor recovery in patients after stroke: Our experience and future directions

    Directory of Open Access Journals (Sweden)

    Plavšić Aleksandra

    2011-01-01

    Full Text Available Introduction. New neurorehabilitation together with conventional techniques provide methods and technologies for maximizing what is preserved from the sensory motor system after cerebrovascular insult. The rehabilitation technique named functional electrical therapy was investigated in more than 60 patients in acute, subacute and chronic phase after cerebrovascular insult. The functional sensory information generated by functional electrical therapy was hypothesized to result in the intensive functional brain training of the activities performed. Functional Electrical Therapy. Functional electrical therapy is a combination of functional exercise and electrical therapy. The functional electrical therapy protocol comprises voluntary movement of the paretic arm in synchrony with the electrically assisted hand functions in order to perform typical daily activities. The daily treatment of 30 minutes lasts three weeks. The outcome measures include several tests for the evaluation of arm/hand functionality: upper extremity function test, drawing test, modified Aschworth scale, motor activity log and passive range of movement. Results of Functional Electrical Therapy Studies. Results from our several clinical studies showed that functional electrical therapy, if applied in acute and subacute stroke patients, leads to faster and greater improvement of functioning of the hemiplegic arm/hand compared to the control group. The outcomes were significantly superior at all times after the treatment for the higher functioning group. Discussion. Additional well-planned clinical studies are needed to determine the adequate dose of treatment (timing, duration, intensity with functional electrical therapy regarding the patient’s status. A combination with other techniques should be further investigated.

  7. Influence of height in neuropsychological functioning and acquisition of motor milestones in children

    Directory of Open Access Journals (Sweden)

    Tomás Caycho Rodríguez

    2014-05-01

    Full Text Available It aims to present a brief review on the effects of height above the sea level in neuropsychological functioning and the acquisition of motor milestones in children. While in Peru, there is no objective data to support such information, the reasoning described here is based on recent findings on the functional importance of the biophysical contexts that suggests the presence of slight alterations sensoperceptive functioning in high altitude conditions.

  8. Mixed eccentricity diagnosis in Inverter-Fed Induction Motors via the Adaptive Slope Transform of transient stator currents

    Science.gov (United States)

    Pons-Llinares, J.; Antonino-Daviu, J.; Roger-Folch, J.; Moríñigo-Sotelo, D.; Duque-Pérez, O.

    2014-10-01

    This paper researches the detection of mixed eccentricity in Inverter-Fed Induction Motors. The classic FFT method cannot be applied when the stator current captured is not in steady state, which is very common in these motors. Therefore, a transform able to detect the time-frequency evolutions of the components present in the transient signal captured must be applied. In order to optimize the result, a method to calculate the theoretical time-frequency evolution of the stator current components is presented, using only the captured current. This previously obtained information enables the use of the proposed transform: the Adaptive Slope Transform, based on appropriately choosing the atom slope in each point analyzed. Thanks to its adaptive characteristics, the time-frequency evolution of the main components in a stator transient current is traced precisely and with high detail in the 2D time-frequency plot obtained. As a consequence, the time-frequency plane characteristic patterns produced by the Eccentricity Related Harmonics are easily and clearly identified enabling a reliable diagnosis. Moreover, the problem of quantifying the presence of the fault is solved presenting a simple and easy to apply method. The transform capabilities have been shown successfully diagnosing an Inverter-Fed Induction Motor with mixed eccentricity during a startup, a decrease in the assigned frequency, and a load variation with and without slip compensation.

  9. Transcranial Alternating Current Stimulation at Beta Frequency: Lack of Immediate Effects on Excitation and Interhemispheric Inhibition of the Human Motor Cortex.

    Science.gov (United States)

    Rjosk, Viola; Kaminski, Elisabeth; Hoff, Maike; Gundlach, Christopher; Villringer, Arno; Sehm, Bernhard; Ragert, Patrick

    2016-01-01

    Transcranial alternating current stimulation (tACS) is a form of noninvasive brain stimulation and is capable of influencing brain oscillations and cortical networks. In humans, the endogenous oscillation frequency in sensorimotor areas peaks at 20 Hz. This beta-band typically occurs during maintenance of tonic motor output and seems to play a role in interhemispheric coordination of movements. Previous studies showed that tACS applied in specific frequency bands over primary motor cortex (M1) or the visual cortex modulates cortical excitability within the stimulated hemisphere. However, the particular impact remains controversial because effects of tACS were shown to be frequency, duration and location specific. Furthermore, the potential of tACS to modulate cortical interhemispheric processing, like interhemispheric inhibition (IHI), remains elusive. Transcranial magnetic stimulation (TMS) is a noninvasive and well-tolerated method of directly activating neurons in superficial areas of the human brain and thereby a useful tool for evaluating the functional state of motor pathways. The aim of the present study was to elucidate the immediate effect of 10 min tACS in the β-frequency band (20 Hz) over left M1 on IHI between M1s in 19 young, healthy, right-handed participants. A series of TMS measurements (motor evoked potential (MEP) size, resting motor threshold (RMT), IHI from left to right M1 and vice versa) was performed before and immediately after tACS or sham using a double-blinded, cross-over design. We did not find any significant tACS-induced modulations of intracortical excitation (as assessed by MEP size and RMT) and/or IHI. These results indicate that 10 min of 20 Hz tACS over left M1 seems incapable of modulating immediate brain activity or inhibition. Further studies are needed to elucidate potential aftereffects of 20 Hz tACS as well as frequency-specific effects of tACS on intracortical excitation and IHI.

  10. Management of motor complications in Parkinson disease: current and emerging therapies.

    Science.gov (United States)

    Espay, Alberto J

    2010-11-01

    Motor fluctuations and dyskinesias are common motor complications that manifest within the first few years from the initiation of therapy in patients with Parkinson disease. These complications negatively affect the quality of life and represent an important source of disability. A growing number of therapeutic options including treatments aimed at prolonging the efficacy of levodopa (eg, selective monoamine oxidase-B inhibitors and catechol-O-methyltransferase inhibitors), administration of longer-acting dopamine agonists (eg, rotigotine, sustained-release ropinirole), and continuous administration of intraduodenal levodopa exist or will soon become available. Patients who maintain a good response to levodopa but continue to experience disabling motor complications despite the best medical management may benefit from a regimen of subcutaneous apomorphine, ideally delivered by a subcutaneous pump, or deep-brain stimulation of the subthalamic nucleus or internal portion of the pallidum. Emerging therapies for motor complications are expected to further enhance continuous (physiologic) delivery of dopaminergic drugs and extend the reach of therapies beyond the dopaminergic system to influence not only the motor but also the vast range of nonmotor complications of this multisystemic disease.

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

    Science.gov (United States)

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

    2008-01-01

    Though stuttering is manifest in its motor characteristics, the cause of stuttering may not relate purely to impairments in the motor system as stuttering frequency is increased by linguistic factors, such as syntactic complexity and length of utterance, and decreased by changes in perception, such as masking or altering auditory feedback. Using functional and diffusion imaging, we examined brain structure and function in the motor and language areas in a group of young people who stutter. During speech production, irrespective of fluency or auditory feedback, the people who stuttered showed overactivity relative to controls in the anterior insula, cerebellum and midbrain bilaterally and underactivity in the ventral premotor, Rolandic opercular and sensorimotor cortex bilaterally and Heschl's gyrus on the left. These results are consistent with a recent meta-analysis of functional imaging studies in developmental stuttering. Two additional findings emerged from our study. First, we found overactivity in the midbrain, which was at the level of the substantia nigra and extended to the pedunculopontine nucleus, red nucleus and subthalamic nucleus. This overactivity is consistent with suggestions in previous studies of abnormal function of the basal ganglia or excessive dopamine in people who stutter. Second, we found underactivity of the cortical motor and premotor areas associated with articulation and speech production. Analysis of the diffusion data revealed that the integrity of the white matter underlying the underactive areas in ventral premotor cortex was reduced in people who stutter. The white matter tracts in this area via connections with posterior superior temporal and inferior parietal cortex provide a substrate for the integration of articulatory planning and sensory feedback, and via connections with primary motor cortex, a substrate for execution of articulatory movements. Our data support the conclusion that stuttering is a disorder related primarily

  12. Motor and functional skills of children with developmental coordination disorder: a pilot investigation of measurement issues.

    Science.gov (United States)

    Rodger, Sylvia; Ziviani, Jenny; Watter, Pauline; Ozanne, Anne; Woodyatt, Gail; Springfield, Elizabeth

    2003-11-01

    This paper reports on the motor and functional outcomes of 20 children with developmental coordination disorder (DCD) aged 4-8 years consecutively referred to a pediatric physiotherapy service. Children with a Movement ABC (M-ABC) score less than the 15th percentile, and with no concurrent medical, sensory, physical, intellectual or neurological impairments, were recruited. The Motor Assessment Outcomes Model (MAOM) [Coster and Haley, Infants and Young Children 4 (1992) 11] provided the theoretical base for measurement selection, and preliminary findings at the activities and participation levels of the model are reported in this article. Children with DCD performed at the lower end of the normal range on the Peabody Developmental Motor Scales (fine motor total score) (M=85.65, SD=12.23). Performance on the Visual Motor Integration Test (VMI) standard scores was within the average range (M=96.15, SD=10.69). Videotaped observations of the children's writing and cutting indicated that 29% were left-handed and that a large proportion of all children (31%) utilized unusual pencil grasp patterns and immature prehension of scissors. Measurement at the participation level involved use of the Pictorial Scale of Perceived Competence and Social Acceptance (PCSA) and Pediatric Evaluation of Disability Inventory (PEDI). Overall, these young children rated themselves towards the more competent and accepted end of the PCSA over the dimensions of physical and cognitive competence and peer and maternal acceptance. The PEDI revealed generally average performance on social (M=49.98, SD=16.62) and mobility function (M=54.71, SD=3.99), however, self-care function was below the average range for age (M=38.01, SD=12.19). The utility of the MAOM as a framework for comprehensive measurement of functional and motor outcomes of DCD in young children is discussed.

  13. Red raspberries can improve motor function in aged rats

    Science.gov (United States)

    BACKGROUND: Many foods rich in antioxidant and anti-inflammatory compounds have been shown to increase health and reduce markers of aging. A number of berry fruits high in polyphenols are known to ameliorate age-related declines in cellular, cognitive and behavioral function in rats. OBJECTIVES: Thi...

  14. Suitability of functional evaluation embedded in serious game rehabilitation exercises to assess motor development across lifespan.

    Science.gov (United States)

    Bonnechère, B; Sholukha, V; Omelina, L; Van Vooren, M; Jansen, B; Van Sint Jan, S

    2017-09-01

    The aim of this study was to determine if the results of activities performed using specially developed serious games for physical rehabilitation could be used as an indicator of the natural maturation and decline of motor control in healthy participants. Eighty-one participants (19 children (5-15 years old), 40 adults (18-65 years old) and 22 aged subjects (60-88 years old) participated in this study. Motions performed were recorded using the Kinect sensor. Three different exercises embedded in the games were used to assess upper limb, trunk and lower limb control. The trial duration and accuracy, measures of gross motor function and fine motor control, respectively, were computed for each participant. ANOVA tests shows statistically significant differences between the three groups for duration (53±15, 27±10 and 119±30s for children, adults and elderly subjects respectively) and accuracy (87±5, 89±10 and 70±8% for children, adults and elderly subjects respectively). The slopes of the curves that approximated the evolution of the performance over various ages are coherent with previous studies about motor control development and physiological decline. The proposed solution, i.e. serious games rehabilitation exercises coupled to motion analysis, seems to be an interesting tool to assess global motor function. Further studies are needed to study the influence of pathologies on the studied parameters. Copyright © 2017. Published by Elsevier B.V.

  15. 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 pthreshold of after discharge production and disease duration. Using the CES parameters at a stimulation 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.

  16. Ionic channel function in action potential generation: current perspective.

    Science.gov (United States)

    Baranauskas, Gytis

    2007-04-01

    Over 50 years ago, Hodgkin and Huxley laid down the foundations of our current understanding of ionic channels. An impressive progress has been made during the following years that culminated in the revelation of the details of potassium channel structure. Nevertheless, even today, we cannot separate well currents recorded in central mammalian neurons. Many modern concepts about the function of sodium and potassium currents are based on experiments performed in nonmammalian cells. The recent recognition of the fast delayed rectifier current indicates that we need to reevaluate the biophysical role of sodium and potassium currents. This review will consider high quality voltage clamp data obtained from the soma of central mammalian neurons in the view of our current knowledge about proteins forming ionic channels. Fast sodium currents and three types of outward potassium currents, the delayed rectifier, the subthreshold A-type, and the D-type potassium currents, are discussed here. An updated current classification with biophysical role of each current subtype is provided. This review shows that details of kinetics of both sodium and outward potassium currents differ significantly from the classical descriptions and these differences may be of functional significance.

  17. Combined transcranial direct current stimulation and robotic upper limb therapy improves upper limb function in an adult with cerebral palsy.

    Science.gov (United States)

    Friel, Kathleen M; Lee, Peter; Soles, Lindsey V; Smorenburg, Ana R P; Kuo, Hsing-Ching; Gupta, Disha; Edwards, Dylan J

    2017-01-01

    Robotic therapy can improve upper limb function in hemiparesis. Excitatory transcranial direct current stimulation (tDCS) can prime brain motor circuits before therapy. We tested safety and efficacy of tDCS plus robotic therapy in an adult with unilateral spastic cerebral palsy (USCP). In each of 36 sessions, anodal tDCS (2 mA, 20 min) was applied over the motor map of the affected hand. Immediately after tDCS, the participant completed robotic therapy, using the shoulder, elbow, and wrist (MIT Manus). The participant sat in a padded chair with affected arm abducted, forearm supported, and hand grasping the robot handle. The participant controlled the robot arm with his affected arm to move a cursor from the center of a circle to each of eight targets (960 movements). Motor function was tested before, after, and six months after therapy with the Wolf Motor Function Test (WMFT) and Fugl-Meyer (FM). Reaching accuracy on the robot task improved significantly after therapy. The WMFT and FM improved clinically meaningful amounts after therapy. The motor map of the affected hand expanded after therapy. Improvements were maintained six months after therapy. Combined tDCS and robotics safely improved upper limb function in an adult with USCP.

  18. Functional reorganization and prediction of motor recovery after a stroke: A graph theoretical analysis of functional networks.

    Science.gov (United States)

    Lee, Jungsoo; Lee, Minji; Kim, Dae-Shik; Kim, Yun-Hee

    2015-01-01

    This study investigated the changes in the network topological configuration of the ipsilesional and contralesional hemispheres after a stroke and the indicators for the prediction of motor recovery using a graph theoretical approach in networks obtained from functional magnetic resonance imaging (fMRI). A longitudinal observational experiments (2 weeks and 1, 3, and 6 months after onset) were conducted on 12 patients after a stroke. We investigated the network reorganization during recovery in the ipsilesional and contralesional hemispheres by examining changes of graph indices related to network randomization. We predicted the recovery of motor function by examining the relationship between specific network measures and improved motor function scores. The ipsilesional hemispheric network showed active reorganization during recovery after a stroke. The randomness of the network significantly increased for 3 months post-stroke. We described an indicator for the prediction of the recovery of motor function from graph indices: the characteristic path length. As the path length of the ipsilesional network was lower immediately after onset, the better recovery could be expected after 3 months. This approach were helpful for understanding dynamic reorganizations of both hemispheric networks after a stroke and finding the implication for recovery.

  19. Energy-Regenerative Braking Control of Electric Vehicles Using Three-Phase Brushless Direct-Current Motors

    OpenAIRE

    Bo Long; Shin Teak Lim; Ji Hyoung Ryu; Kil To Chong

    2013-01-01

    Regenerative braking provides an effective way of extending the driving range of battery powered electric vehicles (EVs). This paper analyzes the equivalent power circuit and operation principles of an EV using regenerative braking control technology. During the braking period, the switching sequence of the power converter is controlled to inverse the output torque of the three-phase brushless direct-current (DC) motor, so that the braking energy can be returned to the battery. Compared with ...

  20. 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.; Schans, C.P. van der

    2017-01-01

    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

  1. 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.

    2017-01-01

    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

  2. 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.; Schans, C.P. van der

    2017-01-01

    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

  3. Towards Dynamic Control of Wettability by Using Functionalized Altitudinal Molecular Motors on Solid Surfaces

    NARCIS (Netherlands)

    London, Gabor; Chen, Kuang-Yen; Carroll, Gregory T.; Feringa, Ben L.

    2013-01-01

    We report the synthesis of altitudinal molecular motors that contain functional groups in their rotor part. In an approach to achieve dynamic control over the properties of solid surfaces, a hydrophobic perfluorobutyl chain and a relatively hydrophilic cyano group were introduced to the rotor part o

  4. No interrelation of motor planning and executive functions across young ages

    Directory of Open Access Journals (Sweden)

    Kathrin Wunsch

    2016-07-01

    Full Text Available The present study examined the developmental trajectories of motor planning and executive functioning in children. To this end, we tested 217 participants with three motor tasks, measuring anticipatory planning abilities (i.e. the bar-transport-task, the sword-rotation-task and the grasp-height-task, and three cognitive tasks, measuring executive functions (i.e. the Tower-of-Hanoi-task, the Mosaic-task, and the D2-attention-endurance-task. Children were aged between 3 and 10 years and were separated into age groups by one-year bins, resulting in a total of eight groups of children and an additional group of adults. Results suggested (1 a positive developmental trajectory for each of the sub-tests, with better task performance as children get older; (2 that the performance in the separate tasks was not correlated across participants in the different age groups; and (3 that there was no relationship between performance in the motor tasks and in the cognitive tasks used in the present study when controlling for age. These results suggest that both, motor planning and executive functions are rather heterogeneous domains of cognitive functioning with fewer interdependencies than often suggested.

  5. Development of the Gross Motor Function Classification System for Cerebral Palsy

    Science.gov (United States)

    Rosenbaum, Peter L.; Palisano, Robert J.; Bartlett, Doreen J.; Galuppi, Barbara E.; Russell, Dianne J.

    2008-01-01

    The Gross Motor Function Classification System (GMFCS) for cerebral palsy has been widely used internationally for clinical, research, and administrative purposes. This paper recounts the ideas and work behind the creation of the GMFCS, reports on the lessons learned, and identifies some philosophical challenges inherent in trying to develop an…

  6. Stability of Caregiver-Reported Manual Ability and Gross Motor Function Classifications of Cerebral Palsy

    Science.gov (United States)

    Imms, Christine; Carlin, John; Eliasson, Ann-Christin

    2010-01-01

    Aim: To examine the stability of caregiver-reported classifications of function of children with cerebral palsy (CP) measured 12 months apart. Method: Participants were 86 children (50 males, 36 females) with CP of all motor types and severities who were recruited into a population-based longitudinal study. Children were aged 11 years 8 months (SD…