Journal articles: 'Hand motor control'

1

Werring, D. J. "Improving hand motor control after stroke." Journal of Neurology, Neurosurgery & Psychiatry 80, no. 6 (May 15, 2009): 586. http://dx.doi.org/10.1136/jnnp.2008.165209.

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BURTON, H. "Motor Control of the Hand: Hand Function and the Neocortex." Science 229, no. 4715 (August 23, 1985): 752–53. http://dx.doi.org/10.1126/science.229.4715.752.

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Shibuya, Kenichi, and Naomi Kuboyama. "Bilateral Motor Control during Motor Tasks Involving the Nondominant Hand." Journal of PHYSIOLOGICAL ANTHROPOLOGY 28, no. 4 (2009): 165–71. http://dx.doi.org/10.2114/jpa2.28.165.

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MacWilliams, Jessica, Sneh Patel, Grace Carlock, Sarah Vest, Nancy L. Potter, and Judith L. Fridovich‐Keil. "Hand fine motor control in classic galactosemia." Journal of Inherited Metabolic Disease 44, no. 4 (March 23, 2021): 871–78. http://dx.doi.org/10.1002/jimd.12376.

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Cole, Kelly J. "Hand Motor Control: Maturing an Immature Science." Motor Control 19, no. 2 (April 2015): 131–34. http://dx.doi.org/10.1123/mc.2014-0054.

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In the target article Mark Latash has argued that there is but a single bona-fide theory for hand motor control (referent configuration theory). If this is true, and research is often phenomenological, then we must admit that the science of hand motor control is immature. While describing observations under varying conditions is a crucial (but early) stage of the science of any field, it is also true that the key to maturing any science is to vigorously subject extant theories and budding laws to critical experimentation. If competing theories are absent at the present time is it time for scientists to focus their efforts on maturing the science of hand motor control through critical testing of this long-standing theory (and related collections of knowledge such as the uncontrolled manifold)?

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Cole, Kelly J. "Hand Motor Control: Maturing an Immature Science." Motor Control 19, no. 2 (April 2015): 131–34. http://dx.doi.org/10.1123/mcj.2014-0054.

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Hochberg, Fred H., Stephen U. Harris, and Thomas R. Blattert. "Occupational Hand Cramps: Professional Disorders of Motor Control." Hand Clinics 6, no. 3 (August 1990): 417–28. http://dx.doi.org/10.1016/s0749-0712(21)00884-2.

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Batista, Aaron P., and William T. Newsome. "Visuo-motor control: Giving the brain a hand." Current Biology 10, no. 4 (February 2000): R145—R148. http://dx.doi.org/10.1016/s0960-9822(00)00327-4.

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Lemon, Roger. "L-12 Motor cortex control of hand function." Electroencephalography and Clinical Neurophysiology/Electromyography and Motor Control 97, no. 4 (September 1995): S6. http://dx.doi.org/10.1016/0924-980x(95)92440-w.

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Lindner, Axel. "Motor Control: Parietal Stimulation Prevents Voluntary Hand Movement." Current Biology 28, no. 20 (October 2018): R1200—R1202. http://dx.doi.org/10.1016/j.cub.2018.09.001.

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Ali Zahid, Mohammed, Aboobacker Sidhiq Madathil, and Mr Mohammed Sameer Baig. "Robotic Vehicle with Hand Motion Control Using a RF Module." Asian Journal of Applied Science and Technology 06, no. 02 (2022): 06–02. http://dx.doi.org/10.38177/ajast.2022.6212.

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This paper focuses on the materials, working principle of a robotic vehicle which will be controlled with hand motion. The aim of this research is to enhance industrialization by creating a hand motion controlled robotic vehicle, since it uses hand motion it will be easier to use in automation and various industries. It is also very beneficial for people with disabilities since only hand motion is required. There were various materials that were used in the research. 2 microcontrollers, an accelerometer, RF modules, encoder, decoder, diode, motor driver IC, DC motor and batteries. The microcontrollers are small computers which can be programmed to be utilized in various different ways. The Accelerometer is a PCB or a sensor which detects speed. The RF modules are of two types which are transmitters and receivers and they are components which are used to send data and information wirelessly. The encoder and decoder are used to convert the binary to any n number of output terminals. The diode is used to send the electricity in one direction. The motor driver IC controls the DC motor from the information given by the microcontroller ICs and lastly a 9v Battery will be used to power the system. The arduino software will be used to program the IC so it can perform the required task. The gadget features a receiver circuit that is intended to be worn on top of the user's glove. The vehicle's circuit incorporates an RF receiver, an 8051 CPU, and a Driver IC to power the motors. This method is extremely useful for persons with impairments since it allows a robotic vehicle to drive itself using hand gestures. The person only needs to move his hand to move the car forward, backward, left, or right. As a result, the user is not required to push any buttons

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Park, Wookhyun, Woong Choi, Hanjin Jo, Geonhui Lee, and Jaehyo Kim. "Analysis of Control Characteristics between Dominant and Non-Dominant Hands by Transient Responses of Circular Tracking Movements in 3D Virtual Reality Space." Sensors 20, no. 12 (June 19, 2020): 3477. http://dx.doi.org/10.3390/s20123477.

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Human movement is a controlled result of the sensory-motor system, and the motor control mechanism has been studied through diverse movements. The present study examined control characteristics of dominant and non-dominant hands by analyzing the transient responses of circular tracking movements in 3D virtual reality space. A visual target rotated in a circular trajectory at four different speeds, and 29 participants tracked the target with their hands. The position of each subject’s hand was measured, and the following three parameters were investigated: normalized initial peak velocity (IPV2), initial peak time (IPT2), and time delay (TD2). The IPV2 of both hands decreased as target speed increased. The results of IPT2 revealed that the dominant hand reached its peak velocity 0.0423 s earlier than the non-dominant hand, regardless of target speed. The TD2 of the hands diminished by 0.0218 s on average as target speed increased, but the dominant hand statistically revealed a 0.0417-s shorter TD2 than the non-dominant hand. Velocity-control performances from the IPV2 and IPT2 suggested that an identical internal model controls movement in both hands, whereas the dominant hand is likely more experienced than the non-dominant hand in reacting to neural commands, resulting in better reactivity in the movement task.

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Gerber, Corinna N., Didier L. Gasser, and Christopher John Newman. "Hand Ownership Is Altered in Teenagers with Unilateral Cerebral Palsy." Journal of Clinical Medicine 11, no. 16 (August 19, 2022): 4869. http://dx.doi.org/10.3390/jcm11164869.

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We explored hand ownership in teenagers with unilateral cerebral palsy (UCP) compared with typically developing teenagers. Eighteen participants with UCP and 16 control teenagers participated. We used the rubber hand illusion to test hand ownership (HO). Both affected/non-affected hands (UCP) and dominant/non-dominant hands (controls) were tested during synchronous and asynchronous strokes. HO was assessed by measuring the proprioceptive drift toward the fake hand (as a percentage of arm length) and conducting a questionnaire on subjective HO. Both groups had significantly higher proprioceptive drift in the synchronous stroking condition for both hands. Teenagers with UCP showed a significantly higher proprioceptive drift when comparing their paretic hand (median 3.4% arm length) with the non-dominant hand of the controls (median 1.7% arm length). The questionnaires showed that synchronous versus asynchronous stroking generated a robust change in subjective HO in the control teenagers, but not in the teenagers with UCP. Teenagers with UCP have an altered sense of HO and a distorted subjective experience of HO that may arise from the early dysfunction of complex sensory–motor integration related to their brain lesions. HO may influence motor impairment and prove to be a target for early intervention.

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Lohmann, Johannes, Anna Belardinelli, and Martin V. Butz. "Hands Ahead in Mind and Motion: Active Inference in Peripersonal Hand Space." Vision 3, no. 2 (April 18, 2019): 15. http://dx.doi.org/10.3390/vision3020015.

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According to theories of anticipatory behavior control, actions are initiated by predicting their sensory outcomes. From the perspective of event-predictive cognition and active inference, predictive processes activate currently desired events and event boundaries, as well as the expected sensorimotor mappings necessary to realize them, dependent on the involved predicted uncertainties before actual motor control unfolds. Accordingly, we asked whether peripersonal hand space is remapped in an uncertainty anticipating manner while grasping and placing bottles in a virtual reality (VR) setup. To investigate, we combined the crossmodal congruency paradigm with virtual object interactions in two experiments. As expected, an anticipatory crossmodal congruency effect (aCCE) at the future finger position on the bottle was detected. Moreover, a manipulation of the visuo-motor mapping of the participants’ virtual hand while approaching the bottle selectively reduced the aCCE at movement onset. Our results support theories of event-predictive, anticipatory behavior control and active inference, showing that expected uncertainties in movement control indeed influence anticipatory stimulus processing.

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Downey, John E., Kristin M. Quick, Nathaniel Schwed, Jeffrey M. Weiss, George F. Wittenberg, Michael L. Boninger, and Jennifer L. Collinger. "The Motor Cortex Has Independent Representations for Ipsilateral and Contralateral Arm Movements But Correlated Representations for Grasping." Cerebral Cortex 30, no. 10 (June 4, 2020): 5400–5409. http://dx.doi.org/10.1093/cercor/bhaa120.

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Abstract Motor commands for the arm and hand generally arise from the contralateral motor cortex, where most of the relevant corticospinal tract originates. However, the ipsilateral motor cortex shows activity related to arm movement despite the lack of direct connections. The extent to which the activity related to ipsilateral movement is independent from that related to contralateral movement is unclear based on conflicting conclusions in prior work. Here we investigate bilateral arm and hand movement tasks completed by two human subjects with intracortical microelectrode arrays implanted in the left hand and arm area of the motor cortex. Neural activity was recorded while they attempted to perform arm and hand movements in a virtual environment. This enabled us to quantify the strength and independence of motor cortical activity related to continuous movements of each arm. We also investigated the subjects’ ability to control both arms through a brain–computer interface. Through a number of experiments, we found that ipsilateral arm movement was represented independently of, but more weakly than, contralateral arm movement. However, the representation of grasping was correlated between the two hands. This difference between hand and arm representation was unexpected and poses new questions about the different ways the motor cortex controls the hands and arms.

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Prada, Valeria, Laura Mori, Elena Prato, Mehrnaz Hamedani, Accogli Susanna, Grandis Marina, and Schenone Angelo. "Comparison of Strength and Dexterity in Professional and Student Violinists: Setting Foundations to Guide Rehabilitation." Medical Problems of Performing Artists 35, no. 3 (September 1, 2020): 130–37. http://dx.doi.org/10.21091/mppa.2020.3021.

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AIMS: The musician’s hand represents a complex system, which requires important motor skills. Although several studies have already investigated rehabilitation outcomes and techniques in musicians after hand lesions, none have been addressed specifically to objectively quantifiable functional parameters. The purpose of our study was to study hand functionality in violinists in order to provide foundations on which to establish and develop more appropriate rehabilitation protocols. STUDY DESIGN: An observational cross-sectional cohort study consisting of 34 subjects, including 23 students and 11 professional violinists who were either studying or working at a conservatory. Results were compared to a data set of a non-musician control group. METHODS: Nine-hole peg test and hand test system (HTS) were used to perform the study. A hand-held dynamometer was used to measure hand grip and tripod pinch maximal isometric voluntary contraction of both hands. RESULTS: Hand strength did not significantly differ on either side between professional and student violinists. A significant difference was seen when comparing violinists as a whole versus the non-musician control group. HTS highlighted significant differences in dexterity. CONCLUSION: Violinists develop better overall motor performances of the left hand, and their performance is better than normal “non-musician” controls. Dexterity and precision of execution positively correlate to years of practice. We conclude that rehabilitation of a violinist’s hand should be aimed at enhancing motor performance of the left hand and should be focused to maximize dexterity of both hands.

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Said, Radwa Gomaa Abd El-Aziz, Amira M. Abd Elmonem, and Maya G. Aly. "Correlation between selective motor control and upper extremity function in children with hemiparesis." Pakistan Journal of Medical and Health Sciences 15, no. 6 (June 30, 2021): 1709–12. http://dx.doi.org/10.53350/pjmhs211561709.

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Background: Impairedselective motor control is a common problem in children with hemiparesis; it interferes with upper extremity function and grip strength of the affected side. Aim: To study the relationship between selective motor control and upper extremity function in children with hemiparesis. Methods: This study included a convenient sample of 48 children with hemiparesis (age; four to eight years). The test of arm selective control, quality of upper extremity skill test, and hand held dynamometers were used to assess the selective motor control, upper extremityfunction and hand grip strength respectively. Results: The results showed positive significant correlation (p> 0.05) between test of arm selective control with upper extremityfunction (r=0.85) and hand grip strength (r=0.77). Moreover, there was positive significant correlation between upper extremityfunction and hand grip strength (r=0.72). Conclusion: Selective motor control is positively correlated with upper extremityfunction and hand grip strength in children with hemiparesis. The results help in the development of appropriate treatment programs for the rehabilitation of children with hemiplegia. Keywords: Cerebral palsy; Hand grip strength; Selective motor control; Unilateral cerebral palsy; Upper extremity function.

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Jin, Yan, JiWon Seong, YoungChae Cho, and BumChul Yoon. "Effects of aging on motor control strategies during bimanual isometric force control." Adaptive Behavior 27, no. 4 (May 17, 2019): 267–75. http://dx.doi.org/10.1177/1059712319849896.

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Aging-induced degeneration of the neuromuscular system would result in deteriorated complex muscle force coordination and difficulty in executing daily activities that require both hands. The aim of this study was to provide a basic description of how aging and dual-task activity would affect the motor control strategy during bimanual isometric force control in healthy adults. In total, 17 young adults (aged 25.1 ± 2.4 years) and 14 older adults (aged 72.6 ± 3.4 years) participated in the study. The subjects were instructed to press both hands simultaneously to match the 1 Hz sine curve force under two conditions (with or without calculation) with continuous visual feedback. Differences in bimanual motor synergy, bimanual coordination, force accuracy, force variability, and calculation speed were compared. This study found that the specific motor control strategy of older adults involved a decreased bimanual force control ability with both increased VUCM and VORT, and was not influenced by dual tasking. These findings might have implications for establishing interventions for aging-induced hand force control deficits.

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Jacobs, M., A. Premji, and A. J. Nelson. "Plasticity-Inducing TMS Protocols to Investigate Somatosensory Control of Hand Function." Neural Plasticity 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/350574.

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Hand function depends on sensory feedback to direct an appropriate motor response. There is clear evidence that somatosensory cortices modulate motor behaviour and physiology within primary motor cortex. However, this information is mainly from research in animals and the bridge to human hand control is needed. Emerging evidence in humans supports the notion that somatosensory cortices modulate motor behaviour, physiology and sensory perception. Transcranial magnetic stimulation (TMS) allows for the investigation of primary and higher-order somatosensory cortices and their role in control of hand movement in humans. This review provides a summary of several TMS protocols in the investigation of hand control via the somatosensory cortices. TMS plasticity inducing protocols reviewed include paired associative stimulation, repetitive TMS, theta-burst stimulation as well as other techniques that aim to modulate cortical excitability in sensorimotor cortices. Although the discussed techniques may modulate cortical excitability, careful consideration of experimental design is needed to isolate factors that may interfere with desired results of the plasticity-inducing protocol, specifically events that may lead to metaplasticity within the targeted cortex.

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Fuglevand, Andrew J. "Mechanical properties and neural control of human hand motor units." Journal of Physiology 589, no. 23 (November 29, 2011): 5595–602. http://dx.doi.org/10.1113/jphysiol.2011.215236.

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Greg Pitts, Donald, and Shirley Peganoff O’Brien. "Splinting the Hand to Enhance Motor Control and Brain Plasticity." Topics in Stroke Rehabilitation 15, no. 5 (September 2008): 456–67. http://dx.doi.org/10.1310/tsr1505-456.

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Sono, Tálita Saemi Payossim, and Luciano Luporini Menegaldo. "Myoelectric Hand Prosthesis Force Control Through Servo Motor Current Feedback." Artificial Organs 33, no. 10 (October 2009): 871–76. http://dx.doi.org/10.1111/j.1525-1594.2009.00813.x.

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Carneiro, Fernando, Rafael Tavares, José Rodrigues, Paulo Abreu, and Maria Teresa Restivo. "A Gamified Approach for Hand Rehabilitation Device." International Journal of Online Engineering (iJOE) 14, no. 01 (January 25, 2018): 179. http://dx.doi.org/10.3991/ijoe.v14i01.7793.

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<p class="0abstract">This work details developments made in a system for hand rehabilitation, that aims to improve recovery of fine motor control, mostly for those recovering from stroke. The system consists of an instrumented device that is used to interact with a variety of games designed to improve fine motor control, enhancing rehabilitation practices. These games were tested with actual disabled individuals and therapists, having received overall positive feedback.</p>

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Köster, Hannah, Katharina Müller-Schmitz, Aschwin G. J. Kolman, and Rüdiger J. Seitz. "Deficient visuomotor hand coordination in normal pressure hydrocephalus." Journal of Neurology 268, no. 8 (February 17, 2021): 2843–50. http://dx.doi.org/10.1007/s00415-021-10445-5.

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Abstract Objective To investigate if visuomotor coordination of hand movements is impaired in patients with normal pressure hydrocephalus (NPH) identified by dedicated testing procedures. Methods Forty-seven patients admitted for diagnostic workup for suspected NPH were studied prospectively with MRI, testing of cognitive and motor functions, lumbar puncture, and visuomotor coordination of hand movements using the PABLOR-device before and after a spinal tap of 40–50 ml CSF. Statistical analyses were carried out with repeated measures ANOVA and non-parametric correlation analyses. Results Fourteen patients were found to suffer from ideopathic NPH. They were severely impaired in visuomotor control of intermittent arm movements in comparison to patients who were found not to be affected by NPH (n = 18). In the patients with NPH the deficient arm control was improved after the spinal tap in proportion to the improvement of gait. There was no improvement of cognitive and motor functions in the patients not affected by NPH, while the patients with possible NPH (n = 15) showed intermediate deficit and improvement patterns. Interpretation: Our data underline the importance of a multiparametric assessment of NPH and provide evidence for a motor control deficit in idiopathic NPH involving leg and arm movements. It is suggested that this motor control deficit resulted from an affection of the output tracts from the supplementary motor area in the periventricular vicinity.

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Imran, Omar A., Wisam Najm al-din Abed, and Ali N. Jbarah. "Speed control of universal motor." International Journal of Power Electronics and Drive Systems (IJPEDS) 10, no. 1 (March 1, 2019): 41. http://dx.doi.org/10.11591/ijpeds.v10.i1.pp41-47.

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Universal Motors (UM) are normally used for driving portable apparatus such as hand tool machines, vacuum cleaners and most domestic apparatus. The importance of UM is due to its own advantages such as high starting torque, very powerful in relation to its small size, having a variable speed; and lower cost. So, this paper focus on UM speed control under variable loading conditions. A mathematical model for UM is designed. Two controllers are proposed for controlling the motor speed, output rate controller and output reset controller. Ant Colony Optimization (ACO) is proposed for tuning the controller’s parameters due to its impact on solving different optimization problems. It possesses fast convergence, minimum algorithm parameters required, lower consecution time and give optimal results without needing large number of iterations. The results are compared and discussed accurately, which show the proposed tuning technique work well and give optimal results for both controllers.

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Cramer, Steven C., Gereon Nelles, Judith D. Schaechter, Jill D. Kaplan, Seth P. Finklestein, and Bruce R. Rosen. "A Functional MRI Study of Three Motor Tasks in the Evaluation of Stroke Recovery." Neurorehabilitation and Neural Repair 15, no. 1 (March 2001): 1–8. http://dx.doi.org/10.1177/154596830101500101.

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Functional brain imaging studies have provided insights into the processes related to motor recovery after stroke. The comparative value of different motor activation tasks for probing these processes has received limited study. We hypothesized that dif ferent hand motor tasks would activate the brain differently in controls, and that this would affect control-patient comparisons. Functional magnetic resonance imaging (MRI) was used to evaluate nine control subjects and seven patients with good recov ery after a left hemisphere hemiparetic stroke. The volume of activated brain in bilat eral sensorimotor cortex and four other motor regions was compared during each of three tasks performed by the right hand: index finger tapping, four-finger tapping, and squeezing. In control subjects, activation in left sensorimotor cortex was found to be significantly larger during squeezing as compared with index-finger tapping. When com paring control subjects with stroke patients, patients showed a larger volume of acti vation in right sensorimotor cortex during index-finger tapping but not with four-fin ger tapping or squeezing. In addition, patients also showed a trend toward larger activation volume than controls within left supplementary motor area during index- finger tapping but not during the other tasks. Motion artifact was more common with squeezing than with the tapping tasks. The choice of hand motor tasks used during brain mapping can influence findings in control subjects as well as the differences identified between controls and stroke patients. The results may be useful for future studies of motor recovery after stroke. Key Words: Stroke—Motor recovery—Functional MRI.

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Garry, Michael I., Gary Kamen, and Michael A. Nordstrom. "Hemispheric Differences in the Relationship Between Corticomotor Excitability Changes Following a Fine-Motor Task and Motor Learning." Journal of Neurophysiology 91, no. 4 (April 2004): 1570–78. http://dx.doi.org/10.1152/jn.00595.2003.

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Motor performance induces a postexercise increase in corticomotor excitability that may be associated with motor learning. We investigated whether there are hemispheric differences in the extent and/or time course of changes in corticomotor excitability following a manipulation task (Purdue pegboard) and their relationship with motor performance. Single- and paired-pulse (3 ms) transcranial magnetic stimulation (TMS) was used to assess task-induced facilitation of the muscle evoked potential (MEP) and intracortical inhibition (ICI) for three intrinsic hand muscles acting on digits 1, 2, and 5. Fifteen right-handed subjects performed three 30-s pegboard trials with left or right hand in separate sessions. TMS was applied to contralateral motor cortex before and after performance. Number of pegs placed was higher with the right hand, and performance improved (motor learning) with both hands over the three trials. MEP facilitation following performance was short-lasting (<15 min), selective for muscles engaged in gripping the pegs, and of similar magnitude in left and right hands. ICI was reduced immediately following performance with the right hand, but not the left. The extent of MEP facilitation was positively correlated with motor learning for the right hand only. We conclude that the pegboard task induces a selective, short-lasting change in excitability of corticospinal neurons controlling intrinsic hand muscles engaged in the task. Only left hemisphere changes were related to motor learning. This asymmetry may reflect different behavioral strategies for performance improvement with left and right upper limb in this task or hemispheric differences in the control of skilled hand movements.

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Woytowicz, Elizabeth J., Kelly P. Westlake, Jill Whitall, and Robert L. Sainburg. "Handedness results from complementary hemispheric dominance, not global hemispheric dominance: evidence from mechanically coupled bilateral movements." Journal of Neurophysiology 120, no. 2 (August 1, 2018): 729–40. http://dx.doi.org/10.1152/jn.00878.2017.

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Two contrasting views of handedness can be described as 1) complementary dominance, in which each hemisphere is specialized for different aspects of motor control, and 2) global dominance, in which the hemisphere contralateral to the dominant arm is specialized for all aspects of motor control. The present study sought to determine which motor lateralization hypothesis best predicts motor performance during common bilateral task of stabilizing an object (e.g., bread) with one hand while applying forces to the object (e.g., slicing) using the other hand. We designed an experimental equivalent of this task, performed in a virtual environment with the unseen arms supported by frictionless air-sleds. The hands were connected by a spring, and the task was to maintain the position of one hand while moving the other hand to a target. Thus the reaching hand was required to take account of the spring load to make smooth and accurate trajectories, while the stabilizer hand was required to impede the spring load to keep a constant position. Right-handed subjects performed two task sessions (right-hand reach and left-hand stabilize; left-hand reach and right-hand stabilize) with the order of the sessions counterbalanced between groups. Our results indicate a hand by task-component interaction such that the right hand showed straighter reaching performance whereas the left hand showed more stable holding performance. These findings provide support for the complementary dominance hypothesis and suggest that the specializations of each cerebral hemisphere for impedance and dynamic control mechanisms are expressed during bilateral interactive tasks. NEW & NOTEWORTHY We provide evidence for interlimb differences in bilateral coordination of reaching and stabilizing functions, demonstrating an advantage for the dominant and nondominant arms for distinct features of control. These results provide the first evidence for complementary specializations of each limb-hemisphere system for different aspects of control within the context of a complementary bilateral task.

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Yao, Kunpeng, Dagmar Sternad, and Aude Billard. "Hand pose selection in a bimanual fine-manipulation task." Journal of Neurophysiology 126, no. 1 (July 1, 2021): 195–212. http://dx.doi.org/10.1152/jn.00635.2020.

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We study hand poses selection in bimanual fine motor skills. To understand how roles and control variables are distributed across the hands and fingers, we compared two conditions when unscrewing a screw from a watch face. When the watch face needed positioning, role distribution was strongly influenced by hand dominance; when the watch face was stationary, a variety of hand pose combinations emerged. Control of independent task demands is distributed either across hands or across distinct groups of fingers.

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Marneweck, Michelle, Hsing-Ching Kuo, Ana R. P. Smorenburg, Claudio L. Ferre, Veronique H. Flamand, Disha Gupta, Jason B. Carmel, Yannick Bleyenheuft, Andrew M. Gordon, and Kathleen M. Friel. "The Relationship Between Hand Function and Overlapping Motor Representations of the Hands in the Contralesional Hemisphere in Unilateral Spastic Cerebral Palsy." Neurorehabilitation and Neural Repair 32, no. 1 (January 2018): 62–72. http://dx.doi.org/10.1177/1545968317745991.

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Background. In many children with unilateral spastic cerebral palsy (USCP), the corticospinal tract to the affected hand atypically originates in the hemisphere ipsilateral to the affected hand. Such ipsilateral connectivity is on average a predictor of poor hand function. However, there is high variability in hand function in these children, which might be explained by the complexity of motor representations of both hands in the contralesional hemisphere. Objective. To measure the link between hand function and the size and excitability of motor representations of both hands, and their overlap, in the contralesional hemisphere of children with USCP. Methods. We used single-pulse transcranial magnetic stimulation to measure the size and excitability of motor representations of both hands, and their overlap, in the contralesional hemisphere of 50 children with USCP. We correlated these measures with manual dexterity of the affected hand, bimanual performance, and mirror movement strength. Results. The main and novel findings were (1) the large overlap in contralesional motor representations of the 2 hands and (2) the moderate positive associations of the size and excitability of such shared-site representations with hand function. Such functional associations were not present for overall size and excitability of representations of the affected hand. Conclusions. Greater relative overlap of the affected hand representation with the less-affected hand representation within the contralesional hemisphere was associated with better hand function. This association suggests that overlapping representations might be adaptively “yoked,” such that cortical control of the child’s less-affected hand supports that of the affected hand.

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Huang, Mingming, Quanzhen Huang, Yang Zhang, and Xinjun Guo. "A Comprehensive Optimization Control Method for Hybrid Excitation Synchronous Motor." Mathematical Problems in Engineering 2020 (July 3, 2020): 1–11. http://dx.doi.org/10.1155/2020/1390650.

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Hybrid excitation synchronous motor (HESM) offers the advantages of a convenient flux regulation and a wide range of available speeds. As such, it may be conveniently employed in the fields of electric vehicle and aerospace. In this paper, based on a suitable control strategy for vector and speed partition, we put forward a speed control method for HESM which shows optimal efficiency. On the one hand, our method aims at minimizing the copper loss by an optimal configuration of the q-axis current, the d-axis current, and the excitation current under the constraint voltage at the armature end. On the other hand, we conduct a comprehensive analysis of the effects of the flux-weakening speed coefficient on the operating performance of the motors and suggest a self-adaptive control method to regulate that coefficient and further improve the overall performance of the motors, including their speed-range regulation, their efficiency, and their dynamical properties. The proposed flux-weakening control method has been assessed by simulations and HESM-driven experiments. Results have confirmed the feasibility and optimality of our method.

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Rossi, Andrea, and Carlo Concari. "A Novel BLDC-Like DTC Control Technique for Induction Motors." Advances in Power Electronics 2012 (June 21, 2012): 1–8. http://dx.doi.org/10.1155/2012/986702.

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DC brushless motors are widely adopted for their simplicity of control, even in sensorless configuration, and their high torque density. On the other hand, induction motors are very economical due to the absence of permanent magnets; for the same reason they can easily be driven in the flux-weakening region to attain a wide speed range. Nevertheless, high dynamic induction motors drives, based on field-oriented (FOC) or predictive control, require large amounts of computing power and are rather sensitive to motor parameter variations. This paper presents a simple DTC induction motor control algorithm based on a well-known BLDC control technique, which allows to realize a high dynamic induction motor speed control with wide speed range. The firmware implementation is very compact and occupies a low amount of program memory, comparable to volt-per-Hertz- (V/f-) based control algorithms. The novel control algorithm presents also good performance and low current ripple and can be implemented on a low-cost motion control DSP without resorting to high-frequency PWM.

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Li, Chun Sheng, Hai Bin Zhao, and Hong Wang. "Research on EEG-Based Control of Prosthetic Hand." Advanced Engineering Forum 2-3 (December 2011): 423–26. http://dx.doi.org/10.4028/www.scientific.net/aef.2-3.423.

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The wireless control method is implemented between NEU BCI-II brain-computer interface and DR05 humanoid hand in this paper. A user interface with a set of real-time analysis and control methods is developed based on Lab VIEW platform. Wavelet analysis method is embedded in this framework, which extracts the character of alpha rhythm. 86.7% correct rate is achieved by using this framework to make humanoid hand do six gestures. Electronic disturbance of finger motor is eliminated by adopting wireless method.

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Li, Min, Yi Zhang, Hui Zhang, and Huo Sheng Hu. "An EEG Based Control System for Intelligent Wheelchair." Applied Mechanics and Materials 300-301 (February 2013): 1540–45. http://dx.doi.org/10.4028/www.scientific.net/amm.300-301.1540.

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This paper presents a brain computer interface to control an intelligent wheelchair based on EEG signals. EEG signals are collected and analysed by using Emotiv. After signal processing, the events about motor imagery are generated and the commands are designed and transmitted to intelligent wheelchair. Finally, the system realizes the motion control of the intelligent wheelchair through subject's motor imagery of left hand, right hand and legs. Besides, the events about motor imagery are expressed in the form of virtual movement as the feedback of system. The Experiment results show that the control system is feasible and has better stability. It establishes a basis of practical application for EEG control intelligent wheelchair.

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Buetefisch, Cathrin M., Benjamin Hines, Linda Shuster, Paola Pergami, and Adam Mathes. "Motor demand-dependent improvement in accuracy following low-frequency transcranial magnetic stimulation of left motor cortex." Journal of Neurophysiology 106, no. 4 (October 2011): 1614–21. http://dx.doi.org/10.1152/jn.00048.2011.

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The role of primary motor cortex (M1) in the control of voluntary movements is still unclear. In brain functional imaging studies of unilateral hand performance, bilateral M1 activation is inconsistently observed, and disruptions of M1 using repetitive transcranial magnetic stimulation (rTMS) lead to variable results in the hand motor performance. As the motor tasks differed qualitatively in these studies, it is conceivable that M1 contribution differs depending on the level of skillfulness. The objective of the present study was to determine whether M1 contribution to hand motor performance differed depending on the level of precision of the motor task. Here, we used low-frequency rTMS of left M1 to determine its effect on the performance of a pointing task that allows the parametric increase of the level of precision and thereby increase the level of required precision quantitatively. We found that low-frequency rTMS improved performance in both hands for the task with the highest demand on precision, whereas performance remained unchanged for the tasks with lower demands. These results suggest that the functional relevance of M1 activity for motor performance changes as a function of motor demand. The bilateral effect of rTMS to left M1 would also support the notion of M1 functions at a higher level in motor control by integrating afferent input from nonprimary motor areas.

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Gorniak, Stacey L., Evan D. Collins, Kimberly Goldie Staines, Forrest A. Brooks, and Ricardo V. Young. "The Impact of Musical Training on Hand Biomechanics in String Musicians." HAND 14, no. 6 (April 26, 2018): 823–29. http://dx.doi.org/10.1177/1558944718772388.

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Background: The effects of musical training on the body in professional musicians remain an understudied area, particularly in reference to understanding and managing orthopedic/neuromuscular deviations and injuries in this population. The purpose of this study was to evaluate hand/finger fine motor function in musicians via physical examination as well as laboratory-based evaluations. Methods: Thirteen healthy noninjured young elite string musicians participated in this study. Performance of musicians was compared with healthy age-matched, sex-matched, and handedness-matched nonmusician controls. Results: Musicians exhibited decreased intrinsic muscle strength compared with controls; however, no change in extrinsic muscle strength was found between groups. No between-group differences in overall force control were found; however, Group × Hand (right vs left) interactions were found in force control. Conclusions: These data suggest that musicians are a unique population with respect to: (1) fine motor control of the hand; and (2) exhibit changes in differential hand use. This suggests cortical reorganization of string musicians, such that this population should be studied separately from typical healthy controls with respect to hand function.

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Maeda, Kazutaka, Hiroaki Ishida, Katsumi Nakajima, Masahiko Inase, and Akira Murata. "Functional Properties of Parietal Hand Manipulation–related Neurons and Mirror Neurons Responding to Vision of Own Hand Action." Journal of Cognitive Neuroscience 27, no. 3 (March 2015): 560–72. http://dx.doi.org/10.1162/jocn_a_00742.

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Parietofrontal pathways play an important role in visually guided motor control. In this pathway, hand manipulation-related neurons in the inferior parietal lobule represent 3-D properties of an object and motor patterns to grasp it. Furthermore, mirror neurons show visual responses that are concerned with the actions of others and motor-related activity during execution of the same grasping action. Because both of these categories of neurons integrate visual and motor signals, these neurons may play a role in motor control based on visual feedback signals. The aim of this study was to investigate whether these neurons in inferior parietal lobule including the anterior intraparietal area and PFG of macaques represent visual images of the monkey's own hand during a self-generated grasping action. We recorded 235 neurons related to hand manipulation tasks. Of these, 54 responded to video clips of the monkey's own hand action, the same as visual feedback during that action or clips of the experimenter's hand action in a lateral view. Of these 54 neurons, 25 responded to video clips of the monkey's own hand, even without an image of the target object. We designated these 25 neurons as “hand-type.” Thirty-three of 54 neurons that were defined as mirror neurons showed visual responses to the experimenter's action and motor responses. Thirteen of these mirror neurons were classified as hand-type. These results suggest that activity of hand manipulation-related and mirror neurons in anterior intraparietal/PFG plays a fundamental role in monitoring one's own body state based on visual feedback.

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Bütepage, Judith, Silvia Cruciani, Mia Kokic, Michael Welle, and Danica Kragic. "From Visual Understanding to Complex Object Manipulation." Annual Review of Control, Robotics, and Autonomous Systems 2, no. 1 (May 3, 2019): 161–79. http://dx.doi.org/10.1146/annurev-control-053018-023735.

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Planning and executing object manipulation requires integrating multiple sensory and motor channels while acting under uncertainty and complying with task constraints. As the modern environment is tuned for human hands, designing robotic systems with similar manipulative capabilities is crucial. Research on robotic object manipulation is divided into smaller communities interested in, e.g., motion planning, grasp planning, sensorimotor learning, and tool use. However, few attempts have been made to combine these areas into holistic systems. In this review, we aim to unify the underlying mechanics of grasping and in-hand manipulation by focusing on the temporal aspects of manipulation, including visual perception, grasp planning and execution, and goal-directed manipulation. Inspired by human manipulation, we envision that an emphasis on the temporal integration of these processes opens the way for human-like object use by robots.

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Erdal, Yuksel, Ufuk Emre, Arife Cimen Atalar, and Taskın Gunes. "Alien hand syndrome and migraine with aura: A case report." Cephalalgia 38, no. 13 (March 4, 2018): 1984–87. http://dx.doi.org/10.1177/0333102418763321.

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Background Alien Hand Syndrome (AHS) is an uncontrollable, involuntary, but in appearance, purposeful motor control disorder of the upper extremity. Case report A 42-year-old male patient was admitted to our clinic complaining of involuntary motor activity in his right hand. He had a previous history of migraine with visual aura. The uncontrollable motor control disorder was compatible with Alien Hand Syndrome, which was appearing immediately after the visual aura and before the beginning of headache. Conclusion Alien Hand Syndrome is usually observed with anterior cerebral artery infarction, midline tumors, trauma and several neurodegenerative diseases, but is rarely seen in paroxysmal conditions such as migraine with aura.

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GASKETT, CHRIS, ALEŠ UDE, and GORDON CHENG. "HAND–EYE COORDINATION THROUGH ENDPOINT CLOSED-LOOP AND LEARNED ENDPOINT OPEN-LOOP VISUAL SERVO CONTROL." International Journal of Humanoid Robotics 02, no. 02 (June 2005): 203–24. http://dx.doi.org/10.1142/s0219843605000430.

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We propose a hand-eye coordination system for a humanoid robot that supports bimanual reaching. The system combines endpoint closed-loop and open-loop visual servo control. The closed-loop component moves the eyes, head, arms, and torso, based on the position of the target and the robot's hands, as seen by the robot's head-mounted cameras. The open-loop component uses a motor-motor mapping that is learnt online to support movement when visual cues are not available.

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Setiawan, Joga Dharma, Mochammad Ariyanto, Sri Nugroho, Rifky Ismail, Tedi Purbayanto, and Haeryip Sihombing. "Fuzzy Logic Control for a Soft Exoskeleton Glove Using a Motor-Tendon Actuator." Ingeniería e Investigación 41, no. 1 (January 21, 2021): e81531. http://dx.doi.org/10.15446/ing.investig.v41n1.81531.

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A hand is one of the essential limbs on the human body that is used for daily activities. The aim of this research is to develop a soft exoskeleton hand to assist people with hand deterioration. The developed exo-glove is made of low-cost RTV (room-temperaturevulcanizing) silicone rubber with a motor-tendon actuation system that produces the flexion and extension motion. Here, the actuator converts rotation motion into linear motion from DC motor, while a potentiometer sensor is utilized to measure therotation angle on the actuator system, in which fuzzy logic control (FLC) is employed for controlling the motion of the proposed motor-tendon actuator. To validate the function and mechanism of the developed soft exoskeleton glove, testing was conducted towards the FLC performance on the healthy human hand for various object grasping tests. Based on the test results, this studyshows that the soft glove can be implemented on the human hand as an assistive device.

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Zwolińska, Jolanta, Mariusz Drużbicki, Lidia Perenc, and Andrzej Kwolek. "A method of hand motor control assessment in patients with post-stroke spasticity." Advances in Rehabilitation 31, no. 3 (September 26, 2017): 55–70. http://dx.doi.org/10.1515/rehab-2015-0073.

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Abstract Introduction: In order to assess hand spasticity in post-stroke patients, it is necessary to apply an objective and sensitive method which allows for characterising motor control. It is significant due to the necessity to monitor the effects of the therapeutic process according to the requirements of Evidence-Based Medicine (EBM). The aim of the study was to assess the usefulness of the measurement of pressure generated during a maximal palmar grasp and after its release for evaluating the level of hand motor control in poststroke patients compared to subjective scales. Material and methods: In order to characterise motor control, a numerical indicator calculated on the basis of the measurements of pressure generated during a maximal palmar grasp and after its release was suggested. To perform the measurements, 12 poststroke patients with hemiparesis were included in the study. In the research, the level of hand paresis was assessed with Brunnström Approach, the intensity of spasticity was graded with Modified Ashworth Scale, while hand motor function was classified with Fugl-Meyer Assessment (FMA). Pressure generated during a palmar grasp and after its release as well as palm area were measured with the use of a photometric method. The assessment was made twice, i.e. on the day of admission to the in-patient rehabilitation ward and after a three-week hospital treatment. Results: In the second measurement, a slight decrease in paresis intensity according to Brunnström Approach and lower intensity of spasticity according to Ashworth Scale were noted. A higher number of points in the FMA scale was observed. The values of the suggested indicator changed; however, in no case were these changes statistically significant. Conclusions: 1. Compared to other subjective scales, the usefulness of the measurement of pressure generated during a maximal palmar grasp and after its release for assessing the level of hand motor control in post-stroke patients was not confirmed. 2. The usefulness of the recommended method of spastic hand motor control assessment needs to be verified in further research carried out according to EBM requirements.

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Schmitz-Peiffer, Henning, Elisa Aust, Katharina Linse, Wolfgang Rueger, Markus Joos, Matthias Löhle, Alexander Storch, and Andreas Hermann. "Motor-Independent Cognitive Testing in Motor Degenerative Diseases." Journal of Clinical Medicine 11, no. 3 (February 3, 2022): 814. http://dx.doi.org/10.3390/jcm11030814.

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Cognitive function is tested through speech- or writing-based neuropsychological instruments. The application and validity of those tests is impeded for patients with diseases that affect speech and hand motor skills. We therefore developed a “motor-free” gaze-controlled version of the Trail Making Test (TMT), including a calibration task to assess gaze accuracy, for completion by means of an eye-tracking computer system (ETCS). This electronic TMT version (eTMT) was evaluated for two paradigmatic “motor-neurodegenerative” diseases, Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS). We screened 146 subjects, of whom 44 were excluded, e.g., because of vision deficits. Patients were dichotomized into subgroups with less (ALS−, PD−) or severe motor affection (ALS+, PD+). All 66 patients and all 36 healthy controls (HC) completed the eTMT. Patients with sufficient hand motor control (ALS−, PD−, PD+) and all HC additionally completed the original paper–pencil-based version of the TMT. Sufficient and comparable gaze fixation accuracy across all groups and the correlations of the eTMT results with the TMT results supported the reliability and validity of the eTMT. PD+ patients made significantly more errors than HC in the eTMT-B. We hereby proved the good applicability of a motor-free cognitive test. Error rates could be a particularly sensitive marker of executive dysfunction.

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Song, Shu Zhong, and Jing Zhuo Shi. "Motor Position Detection Unit for Servo Control Application." Advanced Materials Research 383-390 (November 2011): 1235–40. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.1235.

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Rotor position detection is important for motor servo system design. In general, there are two kinds of methods to obtain the position information in real time, sensor or sensorless methods. The sensor methods use position sensors such as optical encoder. This will greatly increase the cost of the system, and the sensor with high precision is difficult to be installed. On the other hand, the sensorless method can reduce the cost, but the reliability and complexity of the algorithm is still the problems. In this paper, a new low-cost integrated position detection unit, which is composed of the integrated position sensor, signal processing hardware and software, is described. The sensor is easy to manufacture and has better precision with the help of signal processing circuit and software based on DSP. The sensor can obtain absolute rotating angle using inductance detection method, and it is originally designed and used for a 2-phase hybrid stepping motor position servo system. Even though the feedback unit is originally designed for a 2-phase hybrid stepping motor, the same unit also can be used with other types of motors.

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Song, Shu Zhong, and Jing Zhuo Shi. "Motor Position Detection Unit for Servo Control Application." Advanced Materials Research 433-440 (January 2012): 6272–78. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.6272.

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Rotor position detection is important for motor servo system design. In general, there are two kinds of methods to obtain the position information in real time, sensor or sensorless methods. The sensor methods use position sensors such as optical encoder. This will greatly increase the cost of the system, and the sensor with high precision is difficult to be installed. On the other hand, the sensorless method can reduce the cost, but the reliability and complexity of the algorithm is still the problems. In this paper, a new low-cost integrated position detection unit, which is composed of the integrated position sensor, signal processing hardware and software, is described. The sensor is easy to manufacture and has better precision with the help of signal processing circuit and software based on DSP. The sensor can obtain absolute rotating angle using inductance detection method, and it is originally designed and used for a 2-phase hybrid stepping motor position servo system. Even though the feedback unit is originally designed for a 2-phase hybrid stepping motor, the same unit also can be used with other types of motors.

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Podbros, Linda Z., and Maria A. Wyke. "Laterality Differences for Speed but Not for Control in Sequential Finger Tapping." Perceptual and Motor Skills 67, no. 3 (December 1988): 927–33. http://dx.doi.org/10.2466/pms.1988.67.3.927.

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Multiple or sequential finger tapping is preferential to the dominant right hand with respect to speed. However, in more complex movement, variables other than speed become important. The present investigation uses a sequential finger-rapping task which permits assessment of between-hands differences with respect to rate and control of movement, with and without vision. 36 right-handed normal adults rapidly tapped their fingers in sequential order on a block (2.54 cm. sq.), trying not to move the block. Analyses of variance (mode × hand) performed for taps and shift of the block show the right hand to be faster than the left hand with and without vision, adding further to the notion that the left hemisphere predominates in increases in rapid movement and in sequencing aspects of motor activity. However, while both hands were steadier with vision than without, there were no between-hand differences with regard to control, suggesting equivalency of cerebral function for factors of manual sequencing other than speed.

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de Andrade Melo, Sibele, Andreea Iancu, Joseph-Omer Dyer, and Robert Forget. "Effects of Hand Vibration on Motor Output in Chronic Hemiparesis." International Journal of Brain Science 2015 (February 18, 2015): 1–9. http://dx.doi.org/10.1155/2015/804206.

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Background. Muscle vibration has been shown to increase the corticospinal excitability assessed by transcranial magnetic stimulation (TMS) and to change voluntary force production in healthy subjects. Objectives. To evaluate the effect of vibration on corticospinal excitability using TMS and on maximal motor output using maximal voluntary contraction (MVC) in individuals with chronic hemiparesis. Methodology. Nineteen hemiparetic and 17 healthy control subjects participated in this study. Motor evoked potentials (MEPs) and MVC during lateral pinch grip were recorded at first dorsal interosseous muscle in a single session before, during, and after one-minute trials of 80 Hz vibration of the thenar eminence. Results. In hemiparetic subjects, vibration increased MEP amplitudes to a level comparable to that of control subjects and triggered a MEP response in 4 of 7 patients who did not have a MEP at rest. Also, vibration increased the maximal rate of force production (dF/dtmax⁡) in both control and hemiparetic subjects but it did not increase MVC. Conclusion. Motor response generated with a descending cortical drive in chronic hemiparetic subjects can be increased during vibration. Vibration could be used when additional input is needed to reveal motor responses and to increase rate of force generation.

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Läppchen, C. H., T. Ringer, J. Blessin, G. Seidel, S. Grieshammer, R. Lange, and F. Hamzei. "Optical illusion alters M1 excitability after mirror therapy: a TMS study." Journal of Neurophysiology 108, no. 10 (November 15, 2012): 2857–61. http://dx.doi.org/10.1152/jn.00321.2012.

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The contralesional primary motor cortex (M1) has been suggested to be involved in the motor recovery after mirror therapy, but whether the ipsilesional M1 is influenced by the contralesional M1 via transcallosal interhemispheric inhibition (IHI) is still unclear. The present study investigated the change of IHI as well as the intracortical inhibition and intracortical facilitation of both M1 induced by training in a mirror with the use of transcranial magnetic stimulation (TMS). In this 2 × 2 factorial design (time × group), healthy subjects exercised standardized motor skills with their right hand on four consecutive days. Either a mirror (mirror group) or a board (control group) was positioned between their hands. Before and after training TMS was applied along with training tests of both hands. Tests were the same motor skills exercised daily by both groups. Tests of the untrained left hand improved significantly more in the mirror group than in the control group after training ( P = 0.02) and showed a close correlation with an increase of intracortical inhibition of M1left. IHI did not show any difference between investigation time points and groups. The present study confirms the previous suggestion of the involvement of the “contralesional” left-side (ipsilateral to the hand behind the mirror) M1 after mirror therapy, which is not mediated by IHI. Even with the same motor skill training (both groups performed same motor skills) but with different visual information, different networks are involved in training-induced plasticity.

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Mistry, Michael, Evangelos Theodorou, Stefan Schaal, and Mitsuo Kawato. "Optimal control of reaching includes kinematic constraints." Journal of Neurophysiology 110, no. 1 (July 1, 2013): 1–11. http://dx.doi.org/10.1152/jn.00794.2011.

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We investigate adaptation under a reaching task with an acceleration-based force field perturbation designed to alter the nominal straight hand trajectory in a potentially benign manner: pushing the hand off course in one direction before subsequently restoring towards the target. In this particular task, an explicit strategy to reduce motor effort requires a distinct deviation from the nominal rectilinear hand trajectory. Rather, our results display a clear directional preference during learning, as subjects adapted perturbed curved trajectories towards their initial baselines. We model this behavior using the framework of stochastic optimal control theory and an objective function that trades off the discordant requirements of 1) target accuracy, 2) motor effort, and 3) kinematic invariance. Our work addresses the underlying objective of a reaching movement, and we suggest that robustness, particularly against internal model uncertainly, is as essential to the reaching task as terminal accuracy and energy efficiency.

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Sato, Daisuke, Koya Yamashiro, Hideaki Onishi, Baba Yasuhiro, Yoshimitsu Shimoyama, and Atsuo Maruyama. "Whole-hand water flow stimulation increases motor cortical excitability: a study of transcranial magnetic stimulation and movement-related cortical potentials." Journal of Neurophysiology 113, no. 3 (February 1, 2015): 822–33. http://dx.doi.org/10.1152/jn.00161.2014.

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Previous studies examining the influence of afferent stimulation on corticospinal excitability have demonstrated that the intensity of afferent stimulation and the nature of the afferents targeted (cutaneous/proprioceptive) determine the effects. In this study, we assessed the effects of whole-hand water immersion (WI) and water flow stimulation (WF) on corticospinal excitability and intracortical circuits by measuring motor evoked potential (MEP) recruitment curves and conditioned MEP amplitudes. We further investigated whether whole-hand WF modulated movement-related cortical activity. Ten healthy subjects participated in three experiments, comprising the immersion of participants' right hands with (whole-hand WF) or without (whole-hand WI) water flow, and no immersion (control). We evaluated MEP recruitment curves produced by a single transcranial magnetic stimulation (TMS) pulse at increasing stimulus intensities, short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF) using the paired TMS technique before and after 15 min of intervention. Movement-related cortical potentials (MRCPs) were evaluated to examine primary motor cortex, supplementary motor area, and somatosensory cortex excitability upon movement before and after whole-hand WF. After whole-hand WF, the slope of the MEP recruitment curve significantly increased, whereas SICI decreased and ICF increased in the contralateral motor cortex. The amplitude of the Bereitschaftspotential, negative slope, and motor potential of MRCPs significantly increased after whole-hand WF. We demonstrated that whole-hand WF increased corticospinal excitability, decreased SICI, and increased ICF, although whole-hand WI did not change corticospinal excitability and intracortical circuits. Whole-hand WF modulated movement-related cortical activity, increasing motor cortex activation for the planning and execution of voluntary movements.

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Journal articles on the topic 'Hand motor control'

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