• Parasites, Hosts and Diseases
• /
• v.22 no.2
• /
• pp.259-266
• /
• 1984

Present study was undertaken to elucidate the changes of the ultrastructure of Naegleria fowleri trophozoite in brain tissue of mice and culture medium. Naegleria fowleri, 0359 strain, which used in this study was cultured in axonic liquid medium, CGVS medium. Each mouse was inoculated with amoebas intranasally under secobarbital anesthesia, and sacrificed on 7th day after the infection. Comparative observation of the ultrastructure of the amoebas in axonic culture and experimentally infected mice brain was done with transmission electron microscope. The results are summarized as follows: 1. The amoebas in mouse brain tissue were round in outline, whereas those of amoebas from axonic culture showed irregular appearance. 2. Mitochondria in the amoebas from axonic culture was oval, round and cylindrical shape and darkly stained, whereas those of the amoebas from mouse brain tissue showed dumbbell shape together with above forms. The stain was not unique, but light and/or dark. 3. Rough endoplasmic reticulum of amoebas in brain tissue was tubular, but from culture it was vesicular or tubular in shape. 4. Emity vacuoles were demonstrated in amoebas from culture, while food vacuoles with myelinated structures were abundant in those from tissue, suggesting a strong phagocytic activity. 5. Mouse brain tissue in ected were extensively destroyed, and Polymorphonuclear leukocytes were infiltrated predominantly with inflammatory lesion. Amoebas were observed in the vicinity of the capillary.

• Cartoon and Animation Studies
• /
• s.36
• /
• pp.217-236
• /
• 2014

This study is a literature analytical process for studying the drawing teaching methods considering the professional characteristics of animation and a principle analytical process for studying the perspective that when teaching methods that consider the function, learning and creative mechanisms of the brain are applied, the animation drawing ability will be effectively increased. In recent years, as an alternative discussion on the educational method of each field, study results applied with brain-based learning principles are being presented. This is not only being applied and implemented for art and drawing education but as overall educational alternatives. On the other hand, animation drawing requires artistic literacy and at the same time requires comprehensive teaching methods that can train the structural knowledge, cognitive sensation and communication method but such professional teaching methods are insufficient. Therefore, the principle of effective education is seen through the brain mechanism and the principle of demonstrating the creativity and learning by the brain is analyzed. In addition, through the fundamental relationship on the picture drawing and the function of the brain, the relationship of the drawing and the brain is identified. As a result, not only for the left brain that observes the cognitive information which can draw the structure and shapes but the right brain which is directly related to the drawing should be developed, but in order to express the creativity, teaching methods that can understand the mechanism of comprehensive brain where physical and psychological factors are expressed should be also developed. It is because the animation drawing education is teaching the methods for demonstrating the characteristics of artistic creativity required for the drawing ability. This process will not only be a foundation for identifying the difference against the previous animation drawing teaching methods, and the brain-based principles will be selected as the core strategic definition for designing the strategy and methodological model of future education.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.4
• /
• pp.229-235
• /
• 2013

In this paper, we investigate several important issues on the implementation of a totally implantable microsystem for brain-machine interface that has been attracting a lot of attention recently. So far most of the scientific research has been focused on the high performance, low power electronics or systems such as neural signal amplifiers and wireless signal transmitters, but the real application of the implantable microsystem is affected significantly by a number of factors, ranging from design of the encapsulation structure to physiological and anatomical characteristics of the brain. In this work, we discuss on the thermal effect of the system, the detecting volume of the neural probes, wireless data transmission and power delivery, and physiological and anatomical factors that are critically important for the actual implementation of a totally brain implantable neural interface microsystem.

• Korean Journal of Biological Psychiatry
• /
• v.18 no.1
• /
• pp.5-14
• /
• 2011

Neuroimaging in psychiatry encompasses the powerful tools available for the in vivo study of brain structure and function. MRI including the volumetry, voxel-base morphometry(VBM) and diffusion tensor imaging (DTI) are useful for assessing brain structure, whereas function MRI, positron emission tomography(PET) and magnetoencephalography(MEG) are well established for probing brain function. These tools are well tolerated by the vast majority of psychiatric patients because they provide a powerful but noninvasive means to directly evaluate the brain. Although neuroimaging technology is currently used only to rule in or rule out general medical conditions as opposed to diagnosing primary mental disorders, it may be used to confirm or make psychiatric diagnoses in the future. In addition, neuroimaging may be valuable for predicting the natural course of psychiatric illness as well as treatment response.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.19 no.1
• /
• pp.137-142
• /
• 2024

Recently, deep learning technology has become those methods as de facto standards in the area of medical data representation. But, deep learning inherently requires a large amount of training data, which poses a challenge for its direct application in the medical field where acquiring large-scale data is not straightforward. Additionally, brain signal modalities also suffer from these problems owing to the high variability. Research has focused on designing deep neural network structures capable of effectively extracting spectro-spatio-temporal characteristics of brain signals, or employing self-supervised learning methods to pre-learn the neurophysiological features of brain signals. This paper analyzes methodologies used to handle small-scale data in emerging fields such as brain-computer interfaces and brain signal-based state prediction, presenting future directions for these technologies. At first, this paper examines deep neural network structures for representing brain signals, then analyzes self-supervised learning methodologies aimed at efficiently learning the characteristics of brain signals. Finally, the paper discusses key insights and future directions for deep learning-based brain signal analysis.

• Korean Journal of Cognitive Science
• /
• v.24 no.1
• /
• pp.1-24
• /
• 2013

The elderly population continues to increase in Korea and there has been a growing interest in understanding normal aging. In response to this public interest, the present paper reviewed human aging research focusing on recently published neuroimaging studies. For the first half of the paper, I reviewed the effects of aging on the brain and cognition. In normal aging, structural changes in the brain include atrophy and volume reduction in the prefrontal and temporal cortices. Functional changes are exhibited in the form of overactivation of the brain. Moreover, age-related cognitive decline is particularly observed in inhibition and memory, which are also associated with the age-related structural changes in the brain. For the second half of the paper, I introduced physical exercise studies showing that exercise played a protective role in the age-related neurocognitive decline. More specifically, engaging in physical exercise (particularly, aerobic exercise) for a relatively long period of time (e. g., > 6 mon.) protected older adults from volume loss in the prefrontal cortex and the hippocampus, and induced better inhibition and memory. These exercise-induced benefits appear to be associated with changes in neuronal levels, indicating that the aging brain is still plastic and this plasticity can be enhanced by physical exercise.

• The Korean Journal of Applied Statistics
• /
• v.29 no.6
• /
• pp.1129-1145
• /
• 2016

Functional neuro-connectivity is one of the main issues in brain science in the sense that it is closely related to neurodynamics in the brain. In the paper, we choose fMRI as a main form of response data to brain activity due to its high resolution. We review methods for analyzing functional neuro-connectivity assuming that measurements are made on physiological responses to neuron activation. This means that we deal with a state-space and measurement model, where the state-space model is assumed to represent neurodynamics. Analysis methods and their interpretation should vary subject to what was measured. We included analysis results of real fMRI data by applying a high-dimensional autoregressive model, which indicated that different neurodynamics were required for solving different types of geometric problems.

• Journal of Digital Contents Society
• /
• v.18 no.2
• /
• pp.239-247
• /
• 2017

In the past, delivering knowledge mainly, education focused on the development of left brain. However, as the importance of right brain is widely accepted, various approaches on education in creativity have been tried. With the advance in the research on the brain, it has been known that the left brain and the right brain are closely linked to work effectively while they are specialized to some functionalities differently. We developed an educational content exploiting Chinese characters to facilitate the balanced development of both brain. Making categorizations from Yin-yang and five elements of the universe, it consists of four stages. The first stage is to stimulate the brain with visual scandal. The second one, third one, and the fourth one are to develop the right brain, left brain, and both brain respectively. Through expert interview, the potential of the developed content as an efficacious method for brain development was verified.

• Investigative Magnetic Resonance Imaging
• /
• v.15 no.2
• /
• pp.110-122
• /
• 2011

Purpose : The purpose of this study is to establish the method generating human brain anatomical connectivity from Korean children and evaluating the network topological properties using small-world network analysis. Materials and Methods : Using diffusion tensor images (DTI) and parcellation maps of structural MRIs acquired from twelve healthy Korean children, we generated a brain structural connectivity matrix for individual. We applied one sample t-test to the connectivity maps to derive a representative anatomical connectivity for the group. By spatially normalizing the white matter bundles of participants into a template standard space, we obtained the anatomical brain network model. Network properties including clustering coefficient, characteristic path length, and global/local efficiency were also calculated. Results : We found that the structural connectivity of Korean children group preserves the small-world properties. The anatomical connectivity map obtained in this study showed that children group had higher intra-hemispheric connectivity than inter-hemispheric connectivity. We also observed that the neural connectivity of the group is high between brain stem and motorsensory areas. Conclusion : We suggested a method to examine the anatomical brain network of Korean children group. The proposed method can be used to evaluate the efficiency of anatomical brain networks in people with disease.

• Journal of the Korean Society of Radiology
• /
• v.14 no.5
• /
• pp.585-595
• /
• 2020

Magnetic resonance imaging(MRI) has become an important technique for examining changes in human brain structure with neurological disorders. Brain development is a very complex process, and is affected by neurogenesiss and genetic programs. As age increases, structures of the brain change, which can contribute to the formation of brain diseases. Among the various factors, Gender is one of the greatest influential factors that affect the development of a healthy brain. The images were analyzed through various programs found in FSL such as SIENAX, FIRST, and Vertex analysis. Our results show that significant gender-related differences in subcortical areas were observed at the particular age group. The magnitude of these differences between gender and volume varied depending on the area investigated. In this study, we used more advanced 3T MRI for the structural analysis of subcortical structures between each gender. In addition, Vertex Analysis was used to visualize the volumetric differences in subcortical structures between each gender. This study is limited to groups in their 70s, therefore, further studies are needed for wider age groups.