• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.816-821
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• 2013

This paper proposes the design method of low-cost vector control system for induction motor using the ARM Cortex-M4 microcontroller. This MCU can be used instead of expensive DSP to control the home appliances such as refrigerator, air conditioner, washing machine and so on. This paper explains the major features of Cortex-M4 for motor control and how to realize a vector-controlled inverter using it. The developed system is applied to 3-phase induction motor of 200[W] and experimental results show good performance similar to the system using TMS320F28335 DSP.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.571-578
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• 2022

Objective: Cognitive-motor trainings had a positive impact on cognitive function and dual-task trainings led to improvements of global cognitive function. The brain activity of the prefrontal cortex (PFC) is another indicator that can infer cognitive function. This study aims to confirm the usability of the interactive system cognitive-motor training program and the changes in the prefrontal cortex through training. Design: Cross-sectional study Methods: In this study, two cognitive tasks were randomly applied to 20 adults as cognitive-motor training using an interactive system, and the same task was performed using the original method. During all tasks, the brain activity of the prefrontal cortex was measured by the change in oxyhemoglobin (HbO) in real-time using Functional Near-Infrastructure. After performing the tasks, the usability of the developed interactive system was evaluated by a usability questionnaire which consists of five items, and each item consists of a 7-point Likert scale that responds from 1 point to 7 points. Results: The HbO levels were increased during cognitive task performance than at the resting phase. And evaluating the usefulness of the interactive system, a questionnaire result showed that it would be useful for cognitive-motor programs. Conclusions: The cognitive-motor training using the interactive system increased the activity of the prefrontal cortex, and the developed wearable sensor-based interactive system confirmed its usefulness.

• Applied Microscopy
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• v.48 no.4
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• pp.102-109
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• 2018

Multiple synaptic boutons (MSBs) have been reported to be synapse with two or more postsynaptic terminals in one presynaptic terminal. These MSBs are known to be increased by various brain stimuli. In the motor cortex, increased number of MSB was observed in both acrobat training (AC) model and traumatic brain injury (TBI) model. Interestingly one is a physiological stimuli and the other is pathological insult. The purpose of this study is to compare the connectivity of MSBs between AC model and TBI model in the cerebral motor cortex, based on the hypothesis that the connectivity of MSBs might be different according to the models. The motor cortex was dissected from perfused brain of each experimental animal, the samples were prepared for routine transmission electron microscopy. The 60~70 serial sections were mounted on the one-hole grid and MSB was analyzed. The 3-dimensional analysis revealed that 94% of MSBs found in AC model synapse two postsynaptic spines from same dendrite. But, 28% MSBs from TBI models synapse two postsynaptic spines from different dendrite. This imply that the MSBs observed in motor cortex of AC model and TBI model might have different circuits for the processing the information.

• Physical Therapy Korea
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• v.10 no.3
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• pp.17-27
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• 2003

Repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability beyond the duration of the rTMS trains themselves. Depending on rTMS parameters, a lasting inhibition or facilitation of cortical excitability can be induced. Therefore, rTMS of high or low frequency over motor cortex may change certain aspects of motor learning performance and cortical activation. This study investigated the effect of high and low frequency subthreshold rTMS applied to the motor cortex on motor learning of sequential finger movements and brain activation using functional MRI (fMRI). Three healthy right-handed subjects (mean age 23.3) were enrolled. All subjects were trained with sequences of seven-digit rapid sequential finger movements, 30 minutes per day for 5 consecutive days using their left hand. 10 Hz (high frequency) and 1 Hz (low frequency) trains of rTMS with 80% of resting motor threshold and sham stimulation were applied for each subject during the period of motor learning. rTMS was delivered on the scalp over the right primary motor cortex using a figure-eight shaped coil and a Rapid(R) stimulator with two Booster Modules (Magstim Co. Ltd, UK). Functional MRI (fMRI) was performed on a 3T ISOL Forte scanner before and after training in all subjects (35 slices per one brain volume TR/TE = 3000/30 ms, Flip angle $60^{\circ}$, FOV 220 mm, $64{\times}64$ matrix, slice thickness 4 mm). Response time (RT) and target scores (TS) of sequential finger movements were monitored during the training period and fMRl scanning. All subjects showed decreased RT and increased TS which reflecting learning effects over the training session. The subject who received high frequency rTMS showed better performance in TS and RT than those of the subjects with low frequency or sham stimulation of rTMS. In fMRI, the subject who received high frequency rTMS showed increased activation of primary motor cortex, premotor, and medial cerebellar areas after the motor sequence learning after the training, but the subject with low frequency rTMS showed decreased activation in above areas. High frequency subthreshold rTMS on the motor cortex may facilitate the excitability of motor cortex and improve the performance of motor sequence learning in normal subject.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.73-73
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• 2003

Purpose: To determine the motor cortex dysfunction in hemiparetic patients due to deep intracerebral hematoma, authors performed proton magnetic resonance spectroscopy (lH MRS) for the evaluation of biochemical changes in the cortex on affected hemisphere according to axonal injury at the level of internal capsule. Methods: Ten control subjects and 14 patients with documentable hemiparesis of varying severity hemiparesis were included. All the hemiparesis was caused by deep intracerebral hematoma (putaminal and thalamic hemorrhage). In vivo 1H MRS study was performed on a 3T MRI/MRS system using STEAM sequence. As a single-voxel technique, Spectral parameters were: 20 ms TE, 2000 ms TR, 128 averages, 2500 Hz spectral width, and 2048 data points. Results: We found that the mean N-acetylaspartate (NAA)/phosphocreatine (Cr) and NAA/choline (Cho) ratios were significantly decreased in the motor cortex of the hemiparesis patients compared with control subjects. Conclusions: 1H MRS examinations of the motor cortex might help to differentiate distinct clinical entities of hemiparesis and to monitor pharmacological effects in therapeutic trials, providing a quantitative biological marker for motor neuron dysfunction. Acknowledgement: This study was supported by a grant of the Center for Functional and Metabolic Imaging Technology, Ministry of Health & Welfare, Republic of Korea. (02-PJ3-PG6-EV07-000).

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.295-345
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• 2003

This study investigated activation of cerebral cortex in patients with hemiplegia that was caused by neural damage. Key-point control movement therapy of Bobath was performed for 9 weeks in 3 subjects with hemiplegia and fMRI was used to compare and analyze activated degree of cerebral cortex in these subjects. fMRI was conducted using the blood oxygen level-dependent(BOLD) technique at 3.0T MR scanner with a standard head coil. The motor activation task consisted of finger flexion-extension exercise in six cycles(one half-cycles = 8 scans = $3\;sec{\times}\;8\;=\;24\;sec$). Subjects performed this task according to visual stimulus that sign of right hand or left hand twinkled(500ms on, 500ms off). After mapping activation of cerebral motor cortex on hand motor function, below results were obtained. 1. Activation decreased in primary motor area, whereas it increased in supplementary motor area and visual association area(p<.001). 2. Activation was observed in bilateral medial frontal gyrus, middle frontal gyrus of left cerebrum, inferior frontal gyrus, inter-hemispheric, fusiform gyrus of right cerebrum, superior parietal lobule of parietal lobe and precuneus in subjedt 1, parahippocampal gyrus of limbic lobe and cingulate gyrus in subject 2, and inferior frontal gyrus of right frontal lobe, middle frontal gyrus, and inferior parietal lobule of left cerebrum in subject 3 (p<.001). 3. Activation cluster extended in declive of right cellebellum posterior lobe in subject 1, culmen of anterior lobe and declive of posterior lobe in subject 2, and dentate gyrus of anterior lobe, culmen and tuber of posterior lobe in subject 3 (p<.001). In conclusion, these data showed that Key-point control movement therapy of Bobath after stroke affect cerebral cortex activation by increasing efficiency of cortical networks. Therefore mapping of brain neural network activation is useful for plasticity and reorganization of cerebral cortex and cortico-spinal tract of motor recovery mechanisms after stroke.

• Annals of Clinical Neurophysiology
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• v.13 no.1
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• pp.38-43
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• 2011

Background: In the brain, the dominant primary motor cortex (M1) has a greater hand representation area, shows more profuse horizontal connections, and shows a greater reduction in intracortical inhibition after hand exercise than does the non-dominant M1, suggesting a hemispheric asymmetry in M1 plasticity. Methods: We performed a transcranial magnetic stimulation (TMS) study to investigate the hemispheric asymmetry of paired associative stimulation (PAS)-induced M1 plasticity in 9 right-handed volunteers. Motor evoked potentials (MEPs) were measured in the abductor pollicis brevis (APB) muscles of both hands, and MEP recruitment curves were measured at different stimulation intensities, before and after PAS. Results: MEP recruitment curves were significantly enhanced in the dominant, but not the non-dominant M1. Conclusions: These results demonstrate that the dominant M1 has greater PAS-induced plasticity than does the non-dominant M1. This provides neurophysiological evidence for the asymmetrical performance of motor tasks related to handedness.

• Journal of Biomedical Engineering Research
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• v.28 no.1
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• pp.139-147
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• 2007

The aim of this study was to evaluate effects of short-tenn repetitive-bilateral excercise on the activation of motor network using functional magnetic resonance imaging (fMRI). The training program was performed at 1 hr/day, 5 days/week during 6 weeks. Fugl-Meyer Assessments (FMA) were performed every two weeks during the training. We compared cerebral and cerebellar cortical activations in two different tasks before and after the training program: (1) the only unaffected hand movement (Task 1); and (2) passive movements of affected hand by the active movement of unaffected hand (Task 2). fMRI was performed at 3T with wrist flexion-extension movement at 1 Hz during the motor tasks. All patients showed significant improvements of FMA scores in their paretic limbs after training. fMRI studies in Task 1 showed that cortical activations decreased in ipsilateral sensorimotor cortex but increased in contralateral sensorimotor cortex and ipsilateral cerebellum. Task 2 showed cortical reorganizations in bilateral sensorimotor cortex, premotor area, supplemetary motor area and cerebellum. Therefore, this study demonstrated that plastic changes of motor network occurred as a neural basis of the improvement subsequent to repetitive-bilateral excercise using the symmetrical upper-limb ann motion trainer.

• Journal of Acupuncture Research
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• v.21 no.2
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• pp.205-222
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• 2004

Objective: To investigate the effects of acupointed Choksamni(ST36), Kokchi(LI11) and Arbitrary acupoint on NADPH-diaphorase, neuronal nitric oxide synthase(nNOS), neuropeptide Y(NPY) and vasoactive intestinal peptide(VIP) in the cerebral cortex of spontaneously hypertensive rats. Methods: The experimental groups were divided into four groups: Normal, Choksamni(ST36), Kokchi(LI11), arbitrary group. Needles were inserted into acupoints at the depth of 0.5 cm with basic insertion method. Such stimulation was applied continuously for 10 minutes, every other day, for 10 sessions of treatments. Thereafter we evaluated changes in NADPH-d-positive neurons histochemically and changes in nNOS, NPY and VIP-positive neurons immunohistochemically. Results : The optical densities of NADPH-d-positive neurons of all the Choksamni & Kokchi groups were significantly different in all areas of cerebral cortex as compared to arbitrary group. In motor1, sensory2, cingulate2, insular, peripheral, visual cortex there was a significant difference between Choksamni & Kokchi group. The optical densities of nNOS-positive neurons of Choksamni group were significantly different in all areas except for auditory, visual and pisiform cortex and Kokchi group in all areas except for auditory and pisiform cortex as compared to arbitrary group. And there was a significant difference in cingulate1, cingulate2, ectohinal, visual cortex between Choksamni & Kokchi group. The optical densities of NPY neurons of Choksamni group were significantly different in cingulate2, insular, pisiform cortex and Kokchi group in motor1, motor2, sensory1, cingulate2, ectorhinal cortex as compared to arbitrary group. And there was no significant difference between Choksamni & Kokchi group. The optical densities of VIP neurons of Choksamni group were significantly different in all areas except for motor1, auditory cortex and Kokchi group in sensory1, insular, ectorhinal, perirhinal, visual, pisiform cortex as compared to arbitrary group. And there was a significant difference in cingulate1, cingulate2, retrosplenial, auditory corterx between Choksamni & Kokchi group. Conclusion : Our results demonstrated that acupuncture on Choksamni(ST36) & Kokchi(LI11) changes the control activities of the NO system in the cerebral cortex of SHR and according to areas there were significant difference between two groups. In all cerebral cortex areas there were distributed NPY & VIP and there were no significant difference among Choksamni(ST36), Kokchi(LI11) and arbitrary group.

• Annals of Clinical Neurophysiology
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• v.7 no.1
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• pp.20-21
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• 2005

Myoclonus may originate from the cerebral cortex, subcortical structures, brainstem, spinal cord or peripheral nerve. But unilateral upper limb myoclonus related to cortical infarct is an unusual clinical picture. We report a 67-year-old man presented with myoclonus, associated with primary motor cortex infarction.