• Journal of Biomedical Engineering Research
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• v.29 no.5
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• pp.355-363
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• 2008

In order to extract only the alpha activity related signals from EEG recordings, we have applied Constrained Independent Component Analysis (cICA), a new extension of ICA in which some a priori knowledge of the alpha activity is utilized to extract only desired components. Its extraction (or filtering) performance has been compared to that of the conventional band-pass filtering via the scalp alpha power maps and cortical source maps of the alpha activity. Our results demonstrate that the alpha power maps and cortical source maps from the cICA-extracted alpha signals reveal more focalized alpha generating regions of the brain than those from the band-pass filtered alpha EEG signals. Furthermore they match more closely the activated regions of the brain mapped using fMRI, validating our results. We believe that the cICA-based filtering approach of EEG signals is a more effective means of extracting a specific brain activity reflected in EEG signals that will result in more accurate source localization or imaging maps.

• Applied Microscopy
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• v.46 no.4
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• pp.184-187
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• 2016

Neuronal connectivity determines brain function. Therefore, understanding the full map of brain connectivity with functional annotations is one of the most desirable but challenging tasks in science. Current methods to achieve this goal are limited by the resolution of imaging tools and the field of view. Macroscale imaging tools (e.g., magnetic resonance imaging, diffusion tensor images, and positron emission tomography) are suitable for large-volume analysis, and the resolution of these methodologies is being improved by developing hardware and software systems. Microscale tools (e.g., serial electron microscopy and array tomography), on the other hand, are evolving to efficiently stack small volumes to expand the dimension of analysis. The advent of mesoscale tools (e.g., tissue clearing and single plane ilumination microscopy super-resolution imaging) has greatly contributed to filling in the gaps between macroscale and microscale data. To achieve anatomical maps with gene expression and neural connection tags as multimodal information hubs, much work on information analysis and processing is yet required. Once images are obtained, digitized, and cumulated, these large amounts of information should be analyzed with information processing tools. With this in mind, post-imaging processing with the aid of many advanced information processing tools (e.g., artificial intelligence-based image processing) is set to explode in the near future, and with that, anatomic problems will be transformed into informatics problems.

• Progress in Medical Physics
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• v.15 no.1
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• pp.45-53
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• 2004

SPM has been widely applied for comparison studios of the functional image data among groups of patients or individuals under different conditions and these images are from people ranging from children to adults. However, the analysis of children's brain images by using SPM can make children's brain images normalized to an adult's template image and this can result in some errors. So this study created the children's mean MR images based on the Magnetic Resonance Images of 36 normal children (age: 2～6, average age: 4.36, SD age: 1.41, M/F: 17/19), and the children's mean SPECT images by using SPECT images of 13 normal children (age: 2～6, average age: 4.80, SD age: 1.17, M/F: 10/3). We created the Korean children's brain template image, based on those mean images, and then we compared between the positions of the clusters, based on the blood flow, by normalizing ADHD children's SPECT image to Korean children's template image and SPM adult's template image. As a result of the analysis, the variation of the cluster positions was found to be a maximum of 25 ㎜. Therefore, we should be aware that we need to consider the template image and the p-value when we analyze the chlidren's brain image by using SPM.

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.258-264
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• 2007

Spatiotemporal changes of brain rhythmic activity at a certain frequency have been usually monitored in real time using scalp potential maps of multi-channel electroencephalography(EEG) or magnetic field maps of magnetoencephalography(MEG). In the present study, we investigate if it is possible to implement a real-time brain activity monitoring system which can monitor spatiotemporal changes of cortical rhythmic activity on a subject's cortical surface, neither on a sensor plane nor on a standard brain model, with a high temporal resolution. In the suggested system, a frequency domain inverse operator is preliminarily constructed, considering the individual subject's anatomical information, noise level, and sensor configurations. Spectral current power at each cortical vertex is then calculated for the Fourier transforms of successive sections of continuous data, when a single frequency or particular frequency band is given. An offline study which perfectly simulated the suggested system demonstrates that cortical rhythmic source changes can be monitored at the cortical level with a maximal delay time of about 200 ms, when 18 channel EEG data are analyzed under Pentium4 3.4GHz environment. Two sets of artifact-free, eye closed, resting EEG data acquired from a dementia patient and a normal male subject were used to show the feasibility of the suggested system. Factors influencing the computational delay are investigated and possible applications of the system are discussed as well.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.461-467
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• 2002

Signals reduced from the brain had been considered as a noise that is caused by the stochastic process until 1980. The recent non-linear dynamic theory researches, however, reported that these signals are meaningful and deterministic chaos signals in which they show how the brain deals with various information Since this report, a wide range of researches has been carried out and still in progress. Thus, by using the correlational dimension, one of the non-linear analytical methods, the characteristics of the brain signals can be analyzed. In this thesis, the scent of lavender, which stimulates the olfactory sense, is introduced to measure EEG with the International 10-20 electrode system on 16 channels, and to analyze the interrelationship between the original signals before the stimulation and the changed signals after the stimulation. Finally, the effect of the scent stimulation to the brain is analyzed. The purpose of this thesis is to apply these analyzed results to the computerized mapping of the brain signals and possible ways of specifying the source of the brain signals through various medical applications.

• Journal of Acupuncture Research
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• v.20 no.1
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• pp.22-34
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• 2003

Objective : To ascertain whether the concept of the treatment side is associated with changes in the blind spot mapping that represents the brain function. Methods : Among the outpatients who visited to Department of Acupuncture & Moxibustion, National Medical Center from March 2002 to October 2002, we selected 40 clinical trial volunteers that showed right side physiological blind spot more enlarged than left, and underwent the examinations of Department of Opthalmology, National Medical Center for ruling out the pathological conditions. Physiological blind spot maps were used as an integer of brain activity before and after electroacupuncture application on the unilateral ST36 meridian point by dividing 40 subjects into two comparative groups for double-blind controlled study. Results: The significant changes in the blind spots were observed. Electroacupuncture application on the ipsilateral or contralateral ST36 of an enlargement cortical map were associated with the concept of determining the treatment side. In the case of electroacupuncture application on the ipsilateral side of an enlarged blind spot, there were decrease of $4.11{\pm}8.56cm$(17.3%) in blind spot perimetry length(p < 0.05). In the case of contralateral side, there were increase of $3.19{\pm}5.40cm$(13.7%) in blind spot perimetry length(p<0.05). The Differences were statistically significant(p<0.05). Conclusions: We found that eletroacupuncture application was associated with an increase or decrease in the brain function in the view of blind spot changes depending on the treatment side. These results suggest that the traditional acupuncture therapeutic strategy with determining the treatment side has clinical significance in the view of the brain function.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.461-467
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• 2002

Signals produced from the brain had been considered as a noise that is caused by the stochastic process until 1980. The recent non-linear dynamic theory researches, however, reported that these signals are meaningful and deterministic chaos signals in which they show how the brain deals with various information Since this report a wide range of researches has been carried out and still in progress. Thus, by using the correlational dimension, one of the non-linear analytical methods, the characteristics of the brain signals can be analyzed. In this thesis, the scent of lavender, which stimulates the olfactory sense, is introduced to measure EEG with the International 10-20 electrode system on 16 channels, and to analyze the interrelationship between the original signals before the stimulation and the changed signals after the stimulation. Finally, the effect of the scent stimulation to the brain is analyzed. The purpose of this thesis is to apply these analyzed results to the computerized mapping of the brain signals and possible ways of specifying the source of the brain signals through various medical applications.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.348-355
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• 1995

This Investigation was carried out to map the morphological development of serotonin-immunoreactive neurons in the larval brain of the cabbage butterfly, Artogeia rapae, during five larval stages. Both the first instar larva and the second instar larva contained twenty serotonin-immunoreactive (5-HTi) neurons in each brain. The fibres of 5-HTI commissure was interconnected to two cerebral hemispheres in both brains. However, the 5-HTi commissural fibres was Increased in number in the second-instar larva brain. In the brain of the second Insar larva these 5-HTi fibres formed rich arborization in contralateral neuropils, especially In the posterior parts of it. The third-Instar larva braIn, which Included twenty two 5-HTi neurons, had three groups of 5-HTi commissural fibres. In the fourth Instar larva, the number of 5-HTi fibres as well as 5-HTi cell bodies increased in the brain. The fifth-instar larva brain, which contained fifty four 5-HTi cell bodies, showed the largest number of 5-HTi cell bodies In developing larval brains. The 5-HTi fibres formed richest commissural fibres and some of them run parallel to anteroposterior axis.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.204-207
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• 2001

뇌 MR 영상에서 질환을 자동적으로 진단하고 판별하는 작업은 정상인의 뇌 영상과의 비교를 통해서 가능하다. 정상인과의 뇌 영상 비교를 통하여 보다 정확하게 질병에 대한 근거를 제시할 수가 있기 때문에 이러한 접근 방법들이 여러 의료영상 연구 분야에서 시도되고 있다. 정상인의 뇌 영상과의 비교를 위해서는 우선적으로 해결되어야 하는 것이 현재의 대상 영상이 정상인 뇌의 어느 위치의 영상과 일치하는 지를 판별하는 문제이다. 따라서 본 연구는 이러한 뇌 매핑에 사용될 수 있는 특징들을 추출하기 위한 것으로, 뇌 매핑에 사용되는 특징들을 추출하기 위해서 뇌 MR 영상으로부터 대리영역, 뇌영역, 뇌척수액영역 그리고 눈영역을 분할한 후 이들의 윤곽선, 최소사각형과 각 영역들의 픽셀 정보들을 찾아낸다. 이는 추후 연구할 뇌 매핑을 위한 대분류에 사용될 수 있다.

• Mass Spectrometry Letters
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• v.14 no.3
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• pp.57-78
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• 2023

Understanding the chemical composition of the brain helps researchers comprehend various neurological processes effectively. Understanding of the fundamental pathological processes that underpin many neurodegenerative disorders has recently advanced thanks to the advent of innovative bioanalytical techniques that allow high sensitivity and specificity with chemical imaging at high resolution in tissues and cells. Mass spectrometry imaging [MSI] has become more common in biomedical research to map the spatial distribution of biomolecules in situ. The technique enables complete and untargeted delineation of the in-situ distribution characteristics of proteins, metabolites, lipids, and peptides. MSI's superior molecular specificity gives it a significant edge over traditional histochemical methods. Recent years have seen a significant increase in MSI, which is capable of simultaneously mapping the distribution of thousands of biomolecules in the tissue specimen at a high resolution and is otherwise beyond the scope of other molecular imaging techniques. This review aims to acquaint the reader with the MSI experimental workflow, significant recent advancements, and implementations of MSI techniques in visualizing the anatomical distribution of neurochemicals in the human brain in relation to various neurogenerative diseases.