• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.73-79
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• 2009

Purpose: Recently, neurostimulation studies involving manipulation of cortical excitability of the human brain have been increasingly attempted. We investigated whether transcranial direct current stimulation (tDCS) applied to the underlying cerebral cortex, directly induces cortical activation during fMRI scanning. Methods: We recently recruited five healthy subjects without a neurological or psychiatric history and who were right-handed, as verified by the modified Edinburg Handedness Inventory. fMRI was done while constant anodal tDCS was delivered to the underlying SM1 area?? immediately after the pre-stimulation for eighteen minutes. Results: Group analysis yielded an averaged map that showed that the SM1 area and the superior parietal cortex in the ipsilateral hemisphere were activated. The voxel size and peak intensity were, respectively, 82 and 5.22 in the SM1, and 85 and 5.77 in the superior parietal cortex. Conclusion: Cortical activation can be induced by constant anodal tDCS of the underlying motor cortex. This suggests that tDCS may be an effective therapeutic device for enhancing? physical motor function by modulating neural excitability of the motor cortex.

• The Journal of Korean Physical Therapy
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• v.17 no.3
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• pp.421-428
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• 2005

The tenn 'Brain plasticity' has been identified that our central nervous system is continuously being adapted and modulated according to environmental needs and demands, and has been used to encompass the multifarious mechanisms related to learning, development, and recovery from damage to the nervous system. The purpose of this study was to demonstrate cortical reorganization in a 26-year-old right-handed hemiparetic patient with traumatic primary motor cortex (M1) injury, using functional MRI (fMRI). The unaffected (left) primary sensori-motor cortex centered on the precentral knob was activated during unaffected (right) hand movements. However, the medial area of the injured M1 was activated during affected (left) hand movements. It seems that the motor function of the affected hand in this patient was reorganized into the medial area of the injured precentral knob. These investigations provide a great useful information and clinical evidences with the specialized clinician in stroke physical therapy about patient's prognosis and therapeutic guidelines.

• Applied Microscopy
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• v.25 no.1
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• pp.65-74
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• 1995

An immunocytochemical study of GABA-positive neuronal elements was performed at the electron microscopic level to examine subcellular distribution of the inhibitory neurotransmitter in the dog basilar pons. Electron-dense reaction product was observed in neuronal somata and dendritic processes. One or more unlabeled axon terminals made asymmetric synaptic contacts with these GABAergic somatic and dendritic profiles. A large number of GABA-positive axon terminals were also observed. They made symmetric as well as asymmetric synaptic contacts with unlabeled dendritic profiles. In axo-axonic synapses, postsynaptic axon-like processes were consistently GABA-immunoreactive. These observations suggest that the inhibitory local circuit neurons in the dog basilar pons play a major role in cerebro-ponto-cerebellar circuitry by integrating various afferent inputs and conveying them into the cerebellar cortex and the deep cerebellar nuclei.

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.329-332
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• 2002

We have investigated the role of slow inhibitory neurons in spontaneous activity using a model network controlled by stochastic mean field theory based on Integrated-and-Fire excitatory and fast inhibitory neurons. It is found that inputting slow inhibitory neurons to such network induces stable spontaneous activity at a much lower threshold than without slow inhibitory neurons in the network. This threshold range is low enough to be considered as biological threshold of cortical neurons. Only slow inhibitory neurons can give adjustable negative feedback in the network keeping lower rate and lower threshold.

• The Journal of Korean Physical Therapy
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• v.17 no.3
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• pp.391-401
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• 2005

The purpose of this study was to investigate the effect of electrical stimulation(EST) on MAP2(Microtubule Associated Protein 2) expression in cerebral cortex following sciatic nerve crush injury in rats. Twelve Sprague-Dawley adult female rats, six for control and six for experimental, were anesthetized and their sciatic nerves were crushed. The electrical stimulation (EST) was applicated with 3 Hz for 10 minuties in a day for muscles innervated sciatic nerve. The MAP2 expression in cerebral cortex was identified from immunohistochemistry against MAP2. The result of this study were as follow: 1) In control group, MAP2 immunoreactive neurons were observed but there no significant increase for 3 days. 2) MAP2 immunoreactive neurons were increased markably in experimental group than control group. 3) MAP2 immunoreactive neurons were increased markably after applicating with EST in sciatic nerve crush injury induced group from 2nd day. This study showed that the application of EST for muscles after sciatic nerve crushed injury made MAP2 immunoreactive neurons in the cerebral cortex increased. Therefore, the electrical stimulation on the peripheral site, denervated muscle, may facilitate MAP2 expression in the cerebral cortex.

• Proceedings of the Korean Society of Computer Information Conference
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• 2014.01a
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• pp.143-144
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• 2014

본 논문에서는 뇌졸중 환자의 독립적인 재활운동이 가능할 수 있는 시스템을 제안한다. 뇌졸중은 뇌기능의 부분적 또는 전체적으로 급속히 발생한 장애가 상당 기간 이상 지속되는 상태를 의미한다. 이러한 뇌졸중은 상지 운동을 통해 대뇌 운동피질을 활성화하여 재활 할 수 있어, 의학 분야에서는 운동기구를 이용하여 뇌졸중 환자의 재활을 돕고 있다. 하지만 병원이 아닌 가정에서 운동을 하기에는 운동기구에 비용, 작업치료사의 부재와 같은 환경적인 측면으로 무리가 있다. 따라서 본 논문에서는 가정에서 환자가 독립적인 운동을 할 수 있게 MCU와 Android Application을 이용하여 의료진이 환자의 옆에 없더라도 운동이 가능하고 가이드를 제공하는 스마트한 재활운동기기를 개발하였다. 또한 기존의 재활운동기기는 단순히 운동만 할 수 있었다면, 본 연구에서는 Android Application에서 게임을 제공함으로써 보다 즐겁게 운동이 가능하여 재활의지 증가를 기대해볼 수 있다. 뿐만 아니라 환자의 운동 데이터가 실시간으로 저장되어 병원에서 의료진이 환자의 운동 상태를 파악할 수 있도록 구성함으로 써 향후 뇌졸중 환자의 재활연구분야에 도움이 될 것이라 생각한다.

• The Journal of Internal Korean Medicine
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• v.22 no.2
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• pp.263-269
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• 2001

Monoplegia is the paralysis of either the upper or lower limb. Monoplegia is commonly caused by an injury to the cerebral cortex; it is rarely caused by an injury to the internal capsule, brain stem, or spinal cord. Most cerebral cortex is derived from the occlusion of a brain cortex blood vessel due to thrombus or embolus. According to motor homunculus, lower limb monoplegia occurs from limited damage to the most upper part of the primary motor area(Brodmann's area 4, located in precentral gyrus). Clinically, lower limb monoplegia due to brain cortical infarction is commonly misunderstood as monoplegia due to spinal injury because the lesion is situated at the most upper part of precentral gyrus. We had many difficulties in finding lesion on brain CT, but we diagnosed two patients correctly by using an MRI, who have lower limb monoplegia due to brain cortical infarction oriental treatment.

• Biomolecules & Therapeutics
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• v.7 no.3
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• pp.242-248
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• 1999

Diazepam, a benzodiazepine (BDZ) agonist, produces sedation and flumazenil, a BDZ antagonist, blocks these actions. The aim of this study was to examine the effects of BDZs on cortical electroencephalogram (EEG) in rats. The recording electrodes were implanted over the frontal and parietal cortices bilaterally, and the reference and ground electrodes over cerebellum under ketamine anesthesia. To assess the effects of diazepam and flumazenil, rats were injected with diazepam (1 mgHg, i.p.) and/or flumazenil ( 1 mg/kg, i.p.), and the EEG was recorded before and after drugs. Normal awake had theta peak in the spectrum and low amplitude waves, while normal sleep showed large amplitude of slow waves. The powers of delta, theta and alpha bands were increased during sleep compared with during awake. Diazepam reduced the mobility of the rat and induced sleep with intermittent fast spindles and large amplitude of slow activity, and it produced broad peak over betaL band and increased the power of gamma band, which were different from EEG patterns in normal sleep. Saline injection awakened rats and abolished fast spindles for a short period about 2-5 min from EEG pattern during diazepam-induced sleep. Flumazenil blocked both diazepam-induced sleep and decreased the slow activities of delta, theta, alpha and betaL, but not of gamma activity for about 10 min or more. This study may indicate that decrease in power of betaL and betaH bands can be used as the measure of central action of benzodiazepines, and that the EEG parameters of benzodiazepines have to be measured without control over the behavioral state by experimenter.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.458-463
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• 2009

Purpose : Schizencephaly is a uncommon congenital brain anomaly characterized by congenital clefts spanning the cerebral hemispheres from pial surface to lateral ventricles and lined by gray matter. In this study, we investigated the clinical manifestation and radiologic findings of pediatric schizencephaly. Methods : The data of 13 patients who were diagnosed with schizencephaly in Severance Childrens Hospital and Yongdong Severance Hospital from January 2005 to December 2007 were analyzed retrospectively. Results : The mean age at diagnosis was $9.08{\pm}2.67$ months old and ranged from 1 to 30 months. The ratio of male to female patients was 3.33:1. Five (38.5%) patients had bilateral clefts, while 8 (61.5%) had unilateral clefts. Five (38.5%) patients had closed lip clefts, and 4 (30.8%) had opened lip clefts. Four (30.8%) patients had multiple clefts. Associated anomalies showed in all cases. The clinical features consisted of mild unilateral weakness in 7 (53.8%) cases and a hemiparesis was present in 3 (23.1%) patients. A tetraparesis was in 3 (23.1%) patients. There was no difference in motor deficit between unilateral and bilateral clefts. Delayed development was observed in all cases. Epilepsy was present in 7 (53.8%) patients, 5 patients with unilateral clefts and 2 patients with bilateral clefts. Three (42.8%) patients showed intractable seizures. Conclusion : Schizencephaly showed variable clinical manifestations and radiologic findings in association with the types and locations of the clefts. It is necessary to diagnose schizencephaly early and to detect the development of epilepsy. Intensive and large studies of the correlation of clinical outcomes and radiologic findings should be continued for more effective treatment.

• Investigative Magnetic Resonance Imaging
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• v.3 no.1
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• pp.47-52
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• 1999

Purpose : The purpose of this study was aimed to evaluate the BOLD(blood oxygen level dependent) contrast fMRI(functional MR imaging) in the occipital lobe and to compare with the metabolic changes based on H MRS (MR spectroscopy) and MRSI (MR spectroscopic imaging) before and after visual stimulation Materials and Methods : Healthy human volunteers (eight males and two females with 24-30 year age) participated in this study. All of the BOLD fMRI were acquired on a 1.5T MR with EPI during supervised visual stimulation in the occipital lobe. The red flicker with 8Hz was used for visual stimulation. After imaging acquisition, the MR images were transferred into unix workstation and processed with acquired from the same location based on the activation map. MRSI (magnetic resonance spectroscopic imaging) was also acquired to analyze the lactate changes before and after stimulation. Results : The activation maps were successfully produced by BOLD effect due to visual stimulation. NAA (N-acetyle aspartate)/Cr (creatine) ratio varied only from $1.79{\pm}0.28{\;}to{\;}1.88{\pm}0.20$ in activation area before and after stimulation. However, the signal intensity of lactate was elevated $9.48{\pm}4.38$ times higher than before activation. Lactate metabolite images were consistent with the activation maps. Conclusion : The BOLD contrast fMRI is enough sensitive to detect the activated area in human brain during the visual stimulation. Lactate metabolite map presents the evidence of lactate elevation on the same area of activation.