• Clinical Psychopharmacology and Neuroscience
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• 제16권4호
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• pp.489-493
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• 2018

Objective: This study was to identify whether working memory (WM) can be clearly subdivided according to auditory and visual modality. To do this, we administered the most recent and universal clinical WM measures in a mixed psychiatric sample. Methods: A total of 115 patients were diagnosed on the basis of DSM-IV diagnostic criteria and with MINI-Plus 5.0, a structured diagnostic interview. WM subtests of Korean version of Wechsler Adult Intelligence Scale-IV and Korean version of Wechsler Memory Scale-IV were administered to assess WM. Confirmatory factor analysis (CFA) was used to observe whether WM measures fit better to a one-factor or two-factor model. Results: CFA results demonstrated that a two factor model fits the data better than one-factor model as expected. Conclusion: Our study supports a modality model of WM, or the existence of modality-specific WM systems, and thus poses a clinical significance of assessing both auditory and visual WM tests.

• 생물정신의학
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• 제6권1호
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• pp.74-80
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• 1999

본 연구는 항정신병약물의 하나인 클로자핀 사용에 따르는 중요한 부작용 중의 하나인 경련의 기전을 이해하기 위하여 시행되었다. 기존의 클로자핀에 의하여 유발되는 경련모델은 실제 임상상황에 적용시키는데 난점이 있으므로 다른 연구자들의 모델을 변화시켜 본 연구에 이용하였다. 정신분열병의 병태 생리에 단가아민가설이 아직 중요한 위치를 점하고 있을 뿐 아니라, 클로자핀에 의하여 유발되는 경련과 단가아민의 관련성을 시사하는 몇몇 증거에 준하여, 단가아민에 작용하는 약물들이 이 모델에서 어떤 영향을 주는가를 관찰하였다. 연구결과는 다음과 같다. 1) 할로페리돌, 프로프라놀롤, 플루옥세틴의 1회 병합처치는 클로자핀에 의하여 유발되는 간대성 근경련을 감소시켰다. 리탄세린 1회 병합처치는 이 경련에 영향을 주지 않았다. 2) 이미프라민 및 리탄세린의 장기 병합처치는 클로자핀에 의하여 유발되는 간대성 근경련을 증가시켰으며, 플루옥세틴 장기 병합처치는 이 경련을 감소시켰다. 할로페리돌 장기 병합처치는이 경련에 영향을 주지 않았다. 이상의 연구결과는 클로자핀에 의하여 유발되는 간대성 근경련에 도파민, 세로토닌계가 관여되나 노르아드레날린계는 관여되지 않음을 시사한다. 향후 단가아민계 신경전달물질의 수용체 아형에 따른 경련에의 영향을 살펴보는 실험이 보완될 필요가 있다. 이런 실험들을 바탕으로 클로자핀에 의하여 유발되는 경련에 대한 기전이 구체화되고 이에 따른 효율적인 관리지침이 세워지기를 기대한다.

• Animal cells and systems
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• 제2권1호
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• pp.65-69
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• 1998

The hippocampus and prefrontal cortex are regarded as the highest-order association cortices. The hippocampus has been proposed to store "cognitive maps" of external environments, and the prefrontal cortex is known to be involved in the planning of behavior, among other functions. Considering the prominent functional roles played by these structures, it is not surprising to find direct monosynaptic projections from the hippocampus to the prefrontal cortex. Rhythmic stimulation of this projection patterned after the hippocampal EEG theta rhythm induced stable long-term potentiation of field potentials in the prefrontal cortex. Comparison of behavioral correlates of hippocampal and prefrontal cortical neurons during an a-arm radial maze, working memory task shows a striking contrast. Hippocampal neurons exhibit clear place-specific firing patterns, whereas prefrontal cortical neurons do not show spatial selectivity, but are correlated to different stages of the behavioral task. These data lead to the hypothesis that the role of hippocampal projection to the prefrontal cortex is not to impose spatial representations upon prefrontal activity, but to provide a mechanism for learning the spatial context in which particular behaviors are appropriate.propriate.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.967-971
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• 1989

A new system for automatic scoring of 'organization' of the EEG dominant rhythm was constructed and applied to 18 normal subjects and 15 patients. Organization parameters which best represented the 'organization' as judged by 5 neurologists' visual inspection were calculated and the automatic organization scoring was obtained by a linear regression of those organization parameters. Furthermore, values of the regression coefficients were used to study the characteristics of EEG interpretation by each neurologist, and this scoring technique can also be applied to the training of EEG interpretation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.417-420
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• 2004

Caenorhabditis (C) elegans is often used in genetic analysis in neuroscience because its simple organism; an adult hermaphrodite contains only 302 neuron. So the worm is often used to study of cancer, alzheimer disease, aging, etc. To analysis mutant type of the worm, an experienced observer was able to subjectively before, but requirements for objective analysis are now increasing. For this reason, we use automated tracking systems to extract global movement coordinate of the worm. In this paper, we extract features, which are related on reversal and movement of the worm. Using these features, we quantitatively analysis 6 type mutant by movement and reversal characteristic.

• Applied Microscopy
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• 제46권4호
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• pp.171-175
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• 2016

A distinctive neuronal network in the brain is believed to make us unique individuals. Electron microscopy is a valuable tool for examining ultrastructural characteristics of neurons, synapses, and subcellular organelles. A recent technological breakthrough in volume electron microscopy allows large-scale circuit reconstruction of the nervous system with unprecedented detail. Serial-section electron microscopy-previously the domain of specialists-became automated with the advent of innovative systems such as the focused ion beam and serial block-face scanning electron microscopes and the automated tape-collecting ultramicrotome. Further advances in microscopic design and instrumentation are also available, which allow the reconstruction of unprecedentedly large volumes of brain tissue at high speed. The recent introduction of correlative light and electron microscopy will help to identify specific neural circuits associated with behavioral characteristics and revolutionize our understanding of how the brain works.

• 한국의학물리학회지:의학물리
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• 제31권3호
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• pp.35-53
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• 2020

The authors congratulate the cerebrations for the 30 years of the Korean Society of Medical Physics (http://www.ksmp.or.kr/). The paper is published to recognize the anniversary. Geon-Ho Jahng invited Professor Z. H. Cho to join to submit this manuscript because he has been one of the leaders in the field of magnetic resonance imaging (MRI) during the last 40 years. In this review, we describe the development and clinical histories of MRI internationally and domestically. We also discuss diffusion and perfusion MRI, molecular imaging using MRI and MR spectroscopy (MRS), and the hybrid systems, such as positron emission tomography-MRI (PET-MRI), MR-guided focused ultrasound surgery (MRgFUS), and MRI-guided linear accelerators (MRI-LINACs). In each part, we discuss the historical evolution of the developments, technical developments, and clinical applications.

• ETRI Journal
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• 제25권5호
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• pp.401-406
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• 2003

A biometric system determines the identity of a person by measuring physical features that can distinguish that person from others. Since biometric features have many variations and can be easily corrupted by noises and deformations, it is necessary to apply machine learning techniques to treat the data. When applying the conventional machine learning methods in designing a specific biometric system, however, one first runs into the difficulty of collecting sufficient data for each person to be registered to the system. In addition, there can be an almost infinite number of variations of non-registered data. Therefore, it is difficult to analyze and predict the distributional properties of real data that are essential for the system to deal with in practical applications. These difficulties require a new framework of identification and verification that is appropriate and efficient for the specific situations of biometric systems. As a preliminary solution, this paper proposes a simple but theoretically well-defined method based on a statistical test theory. Our computational experiments on real-world data show that the proposed method has potential for coping with the actual difficulties in biometrics.

• 동의생리병리학회지
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• 제30권6호
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• pp.402-411
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• 2016

The concept of the meridian system is originated from an empirical, systematic references in the clinical setting, which does not always require anatomical features. As the principles of systems biology are mainly associated with regulating the body's internal environment to maintain a stable condition, they are closely similar to the theory of the meridian system. In this review, I describe the origin of the concept of the meridian system, current status of research on the meridian system and acupuncture points, and the future directions of the research. To unravel the entity of the meridian system, we have to start from understanding its origin and clinical significance. The meridian system, as a theoretical model of the indications of acupuncture points, can help to understand the interconnections that underlie the pathologies of particular diseases or symptoms. Based on the establishment of clinical data platform for acupuncture research, we can extract novel medical information from the clinical data and generate analytical models that are useful for medical knowledge discovery on acupuncture points in the future.

• Annals of Clinical Neurophysiology
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• 제23권2호
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• pp.69-81
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• 2021

Cortico-cortical evoked potential (CCEP) mapping is a rapidly developing method for visualizing the brain network and estimating cortical excitability. The CCEP comprises the early N1 component the occurs at 10-30 ms poststimulation, indicating anatomic connectivity, and the late N2 component that appears at < 200 ms poststimulation, suggesting long-lasting effective connectivity. A later component at 200-1,000 ms poststimulation can also appear as a delayed response in some studied areas. Such delayed responses occur in areas with changed excitability, such as an epileptogenic zone. CCEP mapping has been used to examine the brain connections causally in functional systems such as the language, auditory, and visual systems as well as in anatomic regions including the frontoparietal neocortices and hippocampal limbic areas. Task-based CCEPs can be used to measure behavior. In addition to evaluations of the brain connectome, single-pulse electrical stimulation (SPES) can reflect cortical excitability, and so it could be used to predict a seizure onset zone. CCEP brain mapping and SPES investigations could be applied both extraoperatively and intraoperatively. These underused electrophysiologic tools in basic and clinical neuroscience might be powerful methods for providing insight into measures of brain connectivity and dynamics. Analyses of CCEPs might enable us to identify causal relationships between brain areas during cortical processing, and to develop a new paradigm of effective therapeutic neuromodulation in the future.