• Journal of the Korean Society of Radiology
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• v.6 no.3
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• pp.173-182
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• 2012

It was well known that working memory highly related with academic achievement. The aim of this study was to investigate the differences of brain activation which visually evoked working memory(encoding and retrieval) through functional Magnetic Resonance Imaging(fMRI) in Higher Academic Achievement Group(HAAG) and Lower Academic Achievement Group(LAAG) of college students. 20 assigned college students participated in fMRI studies. They underwent totally 210 seconds repeated paradigm. Stimulation paradigm composed with resting time and encoding and retrieval seeing the figures from the mirror with head coil. The brain activation maps and their quantification were analyzed by the statistical parametric mapping(SPM99) program from level of significance 95%. HAAG was more significantly higher than LAAG in bilateral prefrontal lobe(brodmann 46) associated with working memory, inferior parietal lobe associated with attention, and visual association area in encoding figures test. Right dosoprefrontal lobe(BA 44), right fusiform gyrus associated with decision of figure and, lingual gyrus were more activated in retrieval test with HAAG. On the other hand, LAAG was more significantly higher than HAAG in cingulate gyrus during encoding test. Thalamus, basal ganglia, cerebellum were more activated in retrieval test. Consequently, We could guess from these results HAAG more effectively executed than LAAG in visual working memory test.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.1 no.1
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• pp.27-39
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• 1990

The neural mechanisms involved in attention deficit hyperactivity disorder are largely unknown. In order to investigate the neuroanatomical lesions of attention deficit hyperactivity disorders and their relationships with psychopathology, Single Photon Emission Computed Tomography(SPECT) using HMPAO was performed in 46 ADHDS and Yale Children's Inventory(YCI), Conners Parent Questionaire and DSM-III-R Questionaire for Disruptive Behavior Disorder were used to assess the psychopathology of ADHDS The results are summarized as follows; 1) 30.4% (14/46) of this series revealed decreased perfusion In SPECT. 2) Regions of hypoperfusion were seen in cerebral cortex(17.4%, 8/46), thalamus(13.0%, 6/46), deep gray matter(8.7%, 4/46), basal ganglia(6.5%, 3/46) and cerebellum(2.2%, 1/ 46). 3) The mean scores of the total YCI revealed significant difference between the two groups(SPECT abnormal versus normal group), and among the subscales, hyperactivity, language and fine-motor subscales showed significant differences between the two groups. Although the relationship between the abnormal findings and specific symptom clusters of ADHDS remains unclear, we can suggest that these abnormal findings could be associated with ADHD, and based on these findings, the ADHDS can be subclassified into two groups. This study can be said to reinforce the current conception of heterogeneity of ADHD.

• Journal of Acupuncture Research
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• v.21 no.4
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• pp.19-29
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• 2004

Objective : The purpose of this study is to present the epidemiological data on patients with a stroke admitted to Department of Acupuncture & Moxibustion, Oriental Medical Hospital Kyung Hee University and to investigate the difference between preceding diseases of stroke. Methods : We reviewed medical records of 700 patients with a stroke admitted to Department of Acupuncture & Moxibustion, Oriental Medical Hospital, Kyung Hee University. Results: The incidence of cerebral infarction was 6.7 times that of cerebral hemorrhage. The incidence in males was 1.28 times of that in females. The incidence of stroke increased with aging and more cerebral hemorrhage occured in lower age group than cerebral infarction. There was higher morbidity in October, during the changing of the seasons, than any other months. Hypertension was the most common preceding disease followed by diabetis mellitus, heart disease, hyperlipidemia, and according to Odds's ratio for Male/Female, the probability of having preceding diseases was higher in females than males. In cerebral infarction, MCA territory was the most frequent lesion sites. Of the cerebral hemorrhage, basal ganglia (60%) was the most commonly involved site which was followed by thalamus(33.3%), cortex (3.3%) and subcortex (2.2%). The most common symptom accompanied by stroke was motor dysfunction which was followed by verbal disturbance, urination disorder and dysphagia. Conclusion : This study showed the trends of stroke in Oriental medical center. We expects that Multicenter cooperative and prospective study including Oriental Medicine will be inspired by this study for establishing more accurate chacteristics of stroke in Korea in the future.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1590-1598
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• 2008

Cell proliferation and differentiation are critical processes in a developing fetal rat brain, during which programmed cell death (PCD) also plays an important role. One of the decisive factors for PCD is Bcl-2 family proteins, where Bax induces cell death, whereas Bcl-2 acts as an inhibitor of PCD. As maternal drinking is known to cause fetal alcohol syndrome (FAS) or malformation of the fetal brain during pregnancy, the objective of the present study was to investigate whether maternal ethanol exposure alters the PCD-related Bax and Bcl-2 protein expression during fetal brain development. Pregnant female rats were orally treated with 10% ethanol and the subsequent expressions of the Bax and Bcl-2 proteins examined in the fetal brain, including the forebrain, midbrain, and hindbrain, from gestational day (GD) 15.5 to GD 19.5, using Western blots, in situ hybridization, and immunohistochemistry. With regard to the ratio of Bcl-2 to Bax proteins (Bcl-2/Bax), the Bax protein was dominant in the forebrain and midbrain of the control GD 15.5 fetuses, except for the hindbrain, when compared with the respective ethanol-treated groups. Moreover, Bcl-2 became dominant in the midbrain of the control GD 17.5 fetuses when compared with the ethanol-treated group, representing an alternation of the natural PCD process by ethanol. Furthermore, a differential expression of the Bcl-2 and Bax proteins was found in the differentiating and migrating zones of the cortex, hippocampus, thalamus, and cerebellum. Thus, when taken together, the present results suggest that ethanol affects PCD in the cell differentiation and migration zones of the prenatal rat brain by modulating Bax and Bcl-2 expression in an age- and area-dependent manner. Therefore, this is the first evidence that ethanol may alter FAS-associated embryonic brain development through the alteration of Bax and Bc1-2 expression.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.985-994
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• 2000

Objective : There are some advantages of trigeminal evoked potential(TEP) recording compared to other somatosensory evoked potential(SSEP) recordings. The trigeminal sensory pathway has a pure sensory nerve branch, a broader receptive field in cerebral cortex, and a shorter pathway. Despite these advantages, there is little agreement as to what constitutes a normal response and what wave forms truly characterize the intraoperative TEP. This study presents the normative data of TEP recorded on the epidural surface of the rat with a platinum ball electrode. Materials & Methods : Under general anesthesia with urethane, the adult Sprague-Dawley male rats(300-350g) were given electrical stimulation with two stainless steel electrodes which were inserted into the subcutaneous layer of the area around whiskers. A reference electrode was positioned in the temporalis muscle ipsilateral to the recording site. Results : TEPs were recorded in the Par I area of somatosensory cortex and recorded most apparently on the point of 2mm posterior from the bregma and 6mm lateral from the midline. The typical wave form consisted of 5 peaks (N1-P1-N2-P2-N3 according to emerging order, upward negativity). Each latency to corresponding peaks was not influenced by the different intensities of stimulation, especially from 1 to 5mA. Average latencies of 5 peaks were in the following order ; 7.7, 11.1, 15, 22.3, 29.4ms. There was also no significant difference between latencies before and after administration of muscle relaxant(pancuronium). For the electrophysiological localization of recorded waves, the action potential of a single unit was recorded with glass microelectrode(filled with 2M NaCl, $3-5M{\Omega}$) in the thalamus of rat. A sharp wave was recorded in the VPM nucleus, in which the latency was shorter than that of N1. This suggests that all 5 peaks were generated by neural activities in the suprathalamic pathway. Conclusion : In terms of recording near-field potentials, our data also suggests that TEP in the rat may be superior to other SSEPs. In overall, these results may afford normative data for the studies of supratentorial lesions such as hydrocephalus or cerebral ischemia which can have an influence on near-field potentials.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.1030-1036
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• 2000

Objective : The aim of this study was to retrospectively analyze the safety and effect of Linac based Photon Knife Radiosugery System(PKRS) for treatment of cerebral arteriovenous malformation. Patients and Methods : The authors analyzed the clinical method and results of ten patients who were followed up more than two years, among the 18 patients who had radiosurgery on arteriovenous malformation from June, 1992, to Dec. 1997, with Linac based Photon knife radiosurgery system(PKRS) which was developed in our hospital. Results : The average age of the patients was 30.4(with the range of 13-49), and the sex was seven males and three females. For the initial clinical symptoms, there were five patients with headache, three with seizure, one with hemiparesis, and one with vomiting. Before the radiosurgery, computed tomography, MRI, and cerebral angiogram were done. For the location of arteriovenous malformation, it was found on six patients of cerebral hemisphere, two of thalamus, one of brainstem, and one of corpus callosum. Regarding the size of nidus, there were seven patients of smaller than 3cm, and three patients of larger than 3cm. Computed tomography, MRI, and cerebral angiogram were done periodically for sixth months, first year, and second year after the radiosurgery of PKRS for the completeness of obliteration. Six cases showed complete obliteration, and four partial obliterations were observed among ten cases, and interestingly, six cases of complete obliteration were observed among seven cases of small AVM of smaller than 3cm(the rate of complete obliteration : 85.7%). All patients tolerated the treatment and no significant complication were seen. Conclusion : In this study, linac based radiosurgery using PKRS onto arteriovenous malformation showed excellent effects, therefore authors believe that it is an ideal method for small sized or deep seated AVM.

• The Journal of the Korea Contents Association
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• v.14 no.12
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• pp.854-862
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• 2014

Attention deficit hyperactivity disorder (ADHD) students' intellctual defects, learning problems, and poor academic achievements seem to be due to significantly lower intelligence compared to the normal students, but rather the characteristic of inability to pay attention at a given time can be seen as the more attributing reason. In this study, a comparison between the ADHD students and the normal students will be performed using a fMRI analysis in order to differentiate the brain function between the two groups during a working memory task performance and to assess the difference in the activated regions of the brain. Clinical survey examinations and fMRI measurements were performed for a group of 26 elementary students from the Incheon area. The stimulus of fMRI was a working memory. Cartography statistically analyzed parameters and the Statistical Package of Social Sciences using single-sample t-test, two-sample t-test, were analyzed by multiple regression analysis, the statistical significance level was p<0.05 in, respectively. The disproportionate developments could be seen in the ADHD students group such as the frontal cortex, parietal cortex, thalamus, and caudate nucleus, among others. In addition, as some students felt the increase in the difficulty of working memory task performance, the orbitofrontal cortex and the hippocampus were activated, which seems to be the result of an effort for looking for an answer. More types of ADHD students needs to be secured as research subjects, and more stimulations for fMRI experiments should be considered as it would be useful in the overall evaluation of brain function.

• Journal of the Korean Magnetic Resonance Society
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• v.7 no.1
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• pp.1-15
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• 2003

PURPOSE - To investigate neurometabolism from the brain destructive lesions and striatal putamen-pallidus regions to the clinically worst side in patients with Parkinson's disease after stereotactic functional neurosurgery. METHODS - Using proton magnetic resonance spectroscopy ($^1$H MRS), fifteen patients (7 males and 8 females; mean age 56.5 years; age range 43-67 years) with Parkinson's disease (PD) were studied to measure N-acetylaspartate (NAA), creatine (Cr), choline-containing compounds (Cho) and lactate (Lac) levels on the neurosurgical lesions of thalamus, globus pallidus and striatal putamen-pallidus regions in a brain. RESULTS - Brain destructive lesion and striatal putamen-pallidus region in PD compared with controls were highly and significantly related to NAA/Cho ratios reduction, respectively (P =0.002, P =0.04), but showed no difference from the same regions of PD prior to neurosergery (P =0.06, P =0.77). Increased lactate peaks at 1.3 ppm were present in all the cerebral lesions, and these resonances were confirmed at a long TE =136 ms, indicating that these signals distinguished from lipids. CONCLUSIONS - Our results suggest that NAA/Cho ratios may provide as a neurometabolite marker for neurochemical changes in brain surgical lesion, and the ratios might be related to functional change of neuropathophysiological status in the striatal putamen-pallidus region of PD. Increase of lactate signals, being remarkable in surgical lesions, could be consistent with a common consequence of surgical necrosis. Therefore, MR spectroscopy could be a sensitive diagnostic tool in monitoring neurometabolic changes in PD with neurosurgical treatment.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.68-78
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• 1993

The pathophysiology and neural mechanism involved in Tourette's and chronic motor tic disorder are highly controversial. In order to investigate the functional abnormalities of brain. In Tourette's and chronic motor tic disorder, 42 children with Tourette's and chronic motor disorder underwent single photon emission computed tomography(SPECT) using Tc-99m-HM-PAO. The results are summarized as follows : 1) 31.0% (13/42) of this series revealed perfusion defect in cerebral cortex. 2) 4.8% (2/42) revealed perfusion defect in basal ganglia. 3) 4.8(2/42) revealed perfusion defect in thalamus. 4) 16.7%(7/42) showed perfusion defect in cerebellum. 5) The frequency of abnormal perfusion showed no significant difference between tic with and without attention deficit hyperactivity disorder. 6) The frequency of abnormal perfusion showed no significant difference between Tourette's and chronic motor tic disorder. These findings support the hypothesis of a possible involvement of brain dysfunction in the production of Tourette's and chronic motor tic disorder, and quantification of blood flow and co-registration with magnetic resonance imaging will increase the validity of this study.

• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.76-86
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• 1994

Objectives: This research was performed in order to observe the neuropsychological implication and functional anatomical source of event related potentials(ERP) by studying of correlations between event related potentials and neuropsychological tests. Methods: The latency and voltage of P100 of visual evoked potential (VEP), and N120 and P300 of event related potentials were studied in 56 patients and their correlations with neuropsychological tests were computed. Results: The tests showing significant correlation with latency P100 were visual continous performance test(VCPT) and contingent continous performance test(CCPT) without any significant correlation with voltage of P100. In latency of N120 category test and verbal IQ of KWIS showed significant correlation, and in voltage of N120, finger tapping test, VCPT, CCPT and digit symbol test displayed significant correlations. The latency of P300 had significant correlation with trail making A test and Stroop test. In the voltage of P300 significant correlations were shown with trail making B test, digit symbol test and Wechsler memory scale, finger tapping test, stroop test, VCPT and CCPT. Conclusion : N120 may be considered to reflect the function of medial frontal lobe and P300 may be considered to be developed from the subcortical connection of medial temporal lobe, hippocampus, thalamus, basal ganglia and medial frontal lobe.