• Journal of Acupuncture Research
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• v.21 no.6
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• pp.177-186
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• 2004

Introduction : Recent studies Suggested that there is a strong correlation between acupuncture stimulation and its related cortical activation. Anther study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture stimulation. In ttis study, we investigated a new acupoint $KI_6$ (照海), which was known as motor-related acupoint and obtained an evidence that the stimulation of $KI_6$ resulted in either negative or positive BOLD response to stimulation. Methods & Results : 1. Subjects and paradigms : Two separate stimulation paradigms were performed on five healthy (aged 22-23 yrs) in this study. First, the paradigm of acupuncture stimulation was that the acupuncture needle was inserted in acupoints $KI_6$, which is located in lateral side of the foot and then continuously twisted(補瀉를 除外한 捻轉法) for 70 seconds for 10 cycles of activation. During rest period (70 seconds), the needle was completed removed from acupoint. Total 60 cycles were performed and 10 images were obtained per cycle. Second, nonacupoint was randomly selected and the same paradigm was performed as acupoint stimulation. The stimulation protocol comprised 10 cycles of alternating. activation and rest (10 images per cycle). Total 60 cycles were performed and each cycle take about 1.5 sec for motor task. Subjects take an at least 15 minutes break before starting anther paradigm. 2. fMRI mapping : Multi-slice functional images were obtained on a 1.5T Magnetom Vision MRI scanner (Simens Medical, Erlangen, Germany) equipped with high performance whole-body gradients. The BOLD T2 * - weighted images were acquired with acho planar imaging sequence (TR = 1.2 sec, TE = 60 msec, and flip angle = $90_{\circ}$). The other sequence parameter are : FOV = 210 mm, matrix=$64{\times}128$ or $64{\times}64$, slice number=10 and slice thickness = 5 or 8 mm. the anatomic images were obtained with Spin-echo T1-weighted images. The resulting images were then anaiyzed with STIMULATE (CMRR, U. of Minnesota) to generate functional maps using a student T-test (p < 0.005) and cluster analysis. Both positive and negative response were evaluated. Conclusions : We have observed the activation of the motor cortex by stimulating motor-related acupoint ($KI_6$). Among five subjects, negative BOLD response was shown in four and positive response in one. All subjects showed positive response to conventional finger flexion-extension task. To understand the detailed mechanisms of correlation between acupuncture stimulation and BOLD fMRI changes and two typs of response, further study strongly required.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.55-62
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• 2005

In this paper, we propose the face recognition system using HNMA(Hippocampal Neuron Modeling Algorithm) which can remodel the cerebral cortex and hippocampal neuron as a principle of a man's brain in engineering, then it can learn the feature-vector of the face images very fast and construct the optimized feature each image. The system is composed of two parts. One is feature-extraction and the other is teaming and recognition. In the feature extraction part, it can construct good-classified features applying PCA(Principal Component Analysis) and LDA(Linear Discriminants Analysis) in order. In the learning part, it cm table the features of the image data which are inputted according to the order of hippocampal neuron structure to reaction-pattern according to the adjustment of a good impression in the dentate gyrus region and remove the noise through the associate memory in the CA3 region. In the CA1 region receiving the information of the CA3, it can make long-term memory learned by neuron. Experiments confirm the each recognition rate, that are face changes, pose changes and low quality image. The experimental results show that we can compare a feature extraction and learning method proposed in this paper of any other methods, and we can confirm that the proposed method is superior to existing methods.

• Progress in Medical Physics
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• v.15 no.4
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• pp.228-236
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• 2004

Retinal ganglion cells transmit visual scene as an action potential to visual cortex through optic nerve. Conventional recording method using single intra- or extra-cellular electrode enables us to understand the response of specific neuron on specific time. Therefore, it is not possible to determine how the nerve impulses in the population of retinal ganglion cells collectively encode the visual stimulus with conventional recording. This requires recording the simultaneous electrical signals of many neurons. Recent advances in multi-electrode recording have brought us closer to understanding how visual information is encoded by population of retinal ganglion cells. We examined how ganglion cells act together to encode a visual scene with multi-electrode array (MEA). With light stimulation (on duration: 2 sec, off duration: 5 sec) generated on a color monitor driven by custom-made software, we isolated three functional types of ganglion cell activities; ON (35.0$\pm$4.4%), OFF (31.4$\pm$1.9%), and ON/OFF cells (34.6$\pm$5.3%) (Total number of retinal pieces = 8). We observed that nearby neurons often fire action potential near synchrony (< 1 ms). And this narrow correlation is seen among cells within a cluster which is made of 6～8 cells. As there are many more synchronized firing patterns than ganglion cells, such a distributed code might allow the retina to compress a large number of distinct visual messages into a small number of ganglion cells.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.3 no.1
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• pp.46-55
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• 1992

The pathophysiology of developmental language disorder is a highly controversial matter. In order to investigate the neural mechanisms involved in developmental language disorders, the authors studied three dimensional regional cerebral blood flow(rCBF) using Tc-99mH-MPAO in 42 children with developmental language disorders. The results are summarized as follows : 1) 61.9% (26/42) of this series revealed decreased perfusion in SPECT. 2) Regions of hypoperfusion were seen in cerebral cortex(47.6%, 20/42), thalamus(33.3%, 14/42), basal ganglia(11.9%, 5/42) and cerebellum(7.1%, 3/42). This study suggests that developmental language disorder could be due to specific functional impairment of the local brain regions which could not detected by conventional investigations such as brain CT or EEG.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.81-100
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• 2000

Transsynaptic tracer이며 신경친화성 virus인 pseudorabies virus(PRV)를 방광(膀胱), 방광유(膀胱兪), 위중(委中) 및 중추(中極)에 주입(注入)한 후 4일간의 생존기간이 경과한 후 희생시켜 면역조직화학침액법(免疫組織化學染色法)에 의하여 뇌척수에 표지된 공통된 영역들을 비교하여 관찰한 결과는 다음과 같다. 1. 방광벽(膀胱壁), 방광유(膀胱兪), 위중(委中) 및 중추(中極)에서 척수에 투사된 영역은 흉수(胸髓), 요수(腰髓) 및 천수(薦髓)에 모두 표지되었으며 공통적으로 표지된 부위는 척수(脊髓)의 층판 IV, V, VII, IX, X영역에 표지되었으나 주로 강하게 표지된 공통된 영역은 층판 VII의 중간외측핵, 가슴기둥 및 층판 X영역이었다. 2. 방광벽(膀胱壁), 방광유(膀胱兪), 위중(委中) 및 중추(中極)에서 뇌(腦)에 투사된 공통된 영역은 연수(延髓)에서는 A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nucleus에서 양성반응을 나타내었다. 솔기핵의 경우 아핵인 불명솔기핵, 창백솔기핵 및 큰솔기핵에서 양성반응을 보였다. 다리뇌에서는 청색반점, Barrington's nucleus, A5세포군 및 삼차신경운동핵에서 양성반응을 보였고, 중뇌에서는 눈돌림신경핵, 눈돌림신경섬유 및 다리핵에서 양성반응을 보였다. 간뇌에서는 시상하부(視床下部)의 뇌실(腦室)곁핵과 시상의 뇌실곁핵에서 양성반응을 보였고 대뇌(大腦)에서는 septal nucleus, 피질(皮質)의 뒷다리영역, 마루엽, 이마엽에서 양성반응을 보였다. 이상의 결과를 종합하면 방광(膀胱)에서 투사되는 뇌척수의 영역과 방광유(膀胱兪)나 위중(委中)에서 투사되는 공통된 표지영역들은 방광(膀胱)과 족태양방광경(足太陽膀胱經) 그리고 그 경락(經絡)의 경혈(經穴)들이 어떤 상관성(相關性)을 가지고 연결(連結)되어 있다는 사실을 실험적으로 알 수 있었다. 특히 방광(膀胱)과 방광유(膀胱兪), 위중(委中)에서 투사된 공통된 표지영역, 즉 배뇨중추인 Barrington's nucleus에 표지되는 것은 내장(內臟)-경락(經絡)이 central autonomic pathway에 의하여 서로 연결되었음을 입증하는 중요한 결과(結果)라고 사려(思慮)된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1253-1258
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• 2012

In the present study, we investigated the effects of Rubus coreanus Miquel (RCM) on memory ability of senescence-accelerated mice (SAM). Prone 8 strains of SAM mice (SAMP8), which is a useful animal for investigating the mechanism of brain aging and senile dementia, were fed a diet containing 100 mg/kg body weight/day of RCM for 8 weeks. Memory ability of mice was examined by using passive avoidance test and Morris water maze test. SAMP8 mice showed remarkable memory impairment compared with senescence-resistant 1 strains of SAM (SAMR1). RCM significantly improved memory ability of SAMP8 mice. In addition, acetylcholineasterase activities decreased in the brain of SAMP8 mice treated with RCM. Taken together, these results suggest that RCM may act as an acetylcholineasterase inhibitor, thereby improving senescence-related memory impairment.

• Journal of Life Science
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• v.23 no.2
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• pp.157-166
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• 2013

This study aimed to investigate whether nociceptin contributes to the alterations in cerebral blood flow (CBF) regulation following postnatal exposure to ethanol in Sprague-Dawley rats. Animals received ethanol twice a day, 2 hr apart, on postnatal 6, 7 and 8 days. The changes in regional CBF (rCBF) in response to the changes in mean arterial blood pressure were determined at 4-, 8-, and 12-week of age by laser-Doppler flowmetry. Hypotension was induced by the gradual withdrawal of blood from arterial catheter, and the reversal of blood pressure was produced by the reinfusion of blood. Expression of nociceptin-like immunoreactivity was determined in dura mater and cerebral cortex using immunohistochemistry. Postnatal exposure to ethanol almost abolished the autoregulation of rCBF in all age groups. Pretreatment with nociceptin but not with [$Nphe^1$]nociceptin(1-13)$NH_2$, a selective competitive nociceptin receptor antagonist, 5 min prior to ethanol administration preserved the autoregulation of rCBF in all age groups. Postnatal exposure to ethanol markedly increased the expressions of nociceptin-like immunoreactivity in the dura mater and cerebral cortex, both of which were significantly inhibited by pretreatment with 7-nitroindazole monosodium salt as well as aminoguanidine 5 min prior to ethanol administration in all age groups. The values of arterial blood gas analysis were not significantly different from the basal levels in all groups. These results suggest that nociceptin deeply contributes to the compensatory mechanisms for the nitric oxide-dependent alterations in CBF autoregulation following postnatal exposure to ethanol.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.260-268
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• 1995

Ischemia results when the decrease in tissue perfusion exceeds the tissues ability to increase an oxygen extraction from the blood. Brain edema has been defined as an abnormal accumulation of fluid within brain parenchyma associated with a volumetric enlargement of the brain tissue. In most instances, the labelling of edema as vasogenic or cytotoxic is only relative. For cerebral protection, there were many possible techniques which could increase or maintain cerebral perfusion and reduce cerebral metabolic demand for oxygen. This study was carried out the effect of mild brain hypothermia which was induced by infusion with cold saline into the carotid artery, during brief episodes of transient global ischemia on postischemic brain edema in rabbit. Eight rabbits were anesthetized with halothane and mechanically ventilated with oxygen. For isolated cerebral perfusion, polyethylene catheter was inserted left carotid artery for infusion of cold saline, external carotid artery was ligated, vertebral arteries were cautherized, right carotid artery was snared for ischemia and femoral artery and vein were also canulated for monitoring and drug treatment. At 3 hours After transient global ischemia, specific gravity of cerebral cortex and hippocampus was compared with no-perfusion group , perfusion with cold saline group and normal group. There was no significant differences in physiologic variables among the groups before transient global ischemia. But during transient global ischemia, brain temperature of perfusion group was decreased when compared to no perfusion group. Specific gravity of cerebral cortex and hippocampus of no-perfusion group and perfusion group was statistically significant when compared to normal group (p<0.01). The results of this study suggested that mild brain hypothermia with intracarotid cold saline infusion during brief episodes of transient global ischemia had decreased postischemic brain edema in rabbit.

• Therapeutic Science for Rehabilitation
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• v.8 no.4
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• pp.7-18
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• 2019

Objective : This systematic review aimed to investigate the impact of transcranial direct current stimulation combined with constraint-induced movement therapy (CIMT) in patients with stroke Methods : PubMed and NDSL databases were employed to review literature published between January 2009 and December 2018. The main search terms were "Transcranial direct current stimulation" or "tDCS," "Constraint-induced movement therapy" or "CIMT," "Upper extremity function," "Upper limb," and "Stroke." Based on the inclusion and exclusion criteria, 6 articles were selected. Furthermore, intervention effects on upper extremity function, activities of daily living, and cortical activity were assessed. Results : The current intensity, application time, and protocol of the CIMT varied the between studies. However, the intervention procedures to perform CIMT immediately after transcranial direct current stimulation was the same. Transcranial direct current stimulation combined with CIMT was effective in improving upper limb function and activities of daily living in patients with stoke and had a significant effect on cerebral cortex activation. Conclusions : This study provides information on transcranial direct current stimulation combined with CIMT for use by clinical therapists. Further studies are needed to standardize the stimulation time, current intensity, and electrode attachment position. Furthermore, randomized controlled trials, including long-term follow up, are needed for larger populations using the most appropriate CIMT protocol.

• Sleep Medicine and Psychophysiology
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• v.26 no.1
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• pp.44-48
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• 2019

Objectives: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. Methods: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. Results: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session ($13.9{\pm}2.6$ vs. $12.2{\pm}3.8$ and $3.6{\pm}0.9$ vs. $3.2{\pm}1.0$ in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. Conclusion: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.