• Journal of the Korean Society for Precision Engineering
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• v.23 no.1 s.178
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• pp.209-215
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• 2006

The present study purposed to examine differences between 20s and 40s in visuospatial performance, the number of activated yokels and cerebral lateralization using functional Magnetic Resonance Imaging (fMRI). For this study, eight college students in their twenties (21.5 years on the average) and six adults in their forties (45.7 years on the average) participated in the experiment. Functional brain images were taken from 37 MRI using the single-shot EPI method. Compared to the twenties the forties showed lower visuospatial performance and longer reaction time. In addition, compared to the twenties the forties had a smaller number of activated yokels and less cerebral lateralization. The results of this study show that people's visuospatial performance and number of activated yokels decrease with aging. In addition, they also suggest that cerebral lateralization decreases in order to supplement the lowering of visuospatial performance, which in turn symmetrizes the activation of the left and right hemisphere.

• Childhood Kidney Diseases
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• v.15 no.1
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• pp.22-28
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• 2011

Hypertension is one of the most common chronic diseases in childhood and adolescence. Untreated hypertension adversely affects many organs including heart, brain, kidney and peripheral arteries. We reviewed the complication of central nervous system caused by pediatric hypertension. Cerebral blood flows are maintained constantly in response to changes in blood pressure by cerebral autoregulation. Severe hypertension which destructs cerebral autoregulation results in acute hypertensive encephalopathy syndrome, ischemic or hemorrhagic stroke. Chronic pediatric hypertension induces learning disability and cognitive defect which are subclinical symptom prior to brain damage caused by severe hypertension. We should consider the effect of hypertension on pediatric brain because appropriate antihypertensive drugs could prevent these complications.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2006.06a
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• pp.119-123
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• 2006

문자는 의사소통의 중요한 매개체 중 하나로 사람이 문자를 인식할 때, 글자의 크기나 모양, 위치, 글 자체 등의 매우 다양한 지각적인 변화에 의한 영향을 크게 받지 않는다. 이는 문자에 대한 처리가 다른 사물과는 다소 다르게 일어나며 머릿속에 추상적인 형태(abstract form)로 저장되어 있음을 의미한다. 이러한 처리과정은 시각단어재인 과정에서 어휘 지식에 접근하기 위한 중요한 단계로 여겨지면서 이와 관련된 대뇌 영역의 국재화 양상에 대한 연구들이 진행되고 있다. 본 연구에서는 한글 시각단어재인에 있어 Cohen과 Dehaene 등이 'visual word form area'주장하고 있는 좌측 ventral occipito-tempoarl region의 대뇌 활성화 양상을 살펴보았다. 실험 결과, 좌측 'VWFA'는 어휘의 친숙성에 우뇌의 대측 지점은 어휘성(lexicality)에 민감한 것으로 나타났다.

• Clinical and Experimental Pediatrics
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• v.49 no.2
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• pp.208-211
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• 2006

Dyke-Davidoff-Masson Syndrome (DDMS) is a rare condition characterized by asymmetry of cerebral hemispheric growth with atrophy on one side, ipsilateral compensatory osseous hypertrophy, and contralateral hemiparesis. We experienced a 17 month-old male who presented with left focal clonic or tonic-clonic seizures accompanied by left hemiparesis and developmental delay. Brain MRIs demonstrated progressive atrophy of the right cerebral hemisphere with dilatation of the lateral ventricle, expansion of the ipsilateral frontal sinus with calvarial thickening, and elevation of the petrous pyramid and orbital roof. Brain SPECT showed a decreased volume of the right hemisphere with reduced blood flow. We therefore report a case of DDMS with a review of the literature.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.313-316
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• 2002

본 연구에서는 기능적 자기공명 영상법(functional magnetic resonance imaging)을 이용하여, 한국어, 일어, 프랑스어, 영어 등 여러 언어를 구사할 수 있는 다중언어화자들을 대상으로 각 언어에 따른 대뇌 언어처리 과정을 알아보고, 그 처리과정이 해당언어의 유창성, 습득시기에 따라 어떻게 달라지는지를 알아보았다. 실험 결과, 언어처리에 있어 핵심적인 역할을 하는 것으로 보고되는 Broca 영역은 언어의 이해와 산출 과정에 모두 관계된 것으로 보이며, 언어의 산출과정에는 언어의 이해과정에 관계되는 영역외에 조음과정에 따른 영역의 활성화가 보고되었다. 또한 언어습득시기와 유창성에 따른 각 언어의 활성화를 살펴보면, 유창성이 높을수록 대뇌 활성화는 줄어들며, 유창성이 낮은 언어조건에서는 언어처리 영역의 활성화 수준이 높아지며 또한 우반구 및 전전두회(prefrontal gyrus)의 활성화가 높아지는 것이 보인다.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.4
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• pp.46-54
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• 2003

In this paper, we propose segmentation algorithm for MR brain images using the histogram of T1-weighted, T2-weighted and PD images. Segmentation algorithm is composed of 3 steps. The first step involves the extraction of cerebrum images by ram a cerebrum mask over three input images. In the second step, peak ranges are determined from the histogram of the cerebrum image. In the final step, cerebrum images are segmented using coarse to fine clustering technique. We compare the segmentation result and processing time according to peak ranges. Also compare with the other segmentation methods. The proposed algorithm achieved better segmentation results than the other methods.

• Journal of the Korean Society of Radiology
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• v.83 no.1
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• pp.206-211
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• 2022

Stenosis of the central veins is a common complication in hemodialysis patients. However, cerebral venous hypertension and neurological symptoms caused by central vein stenosis are relatively rare. We present a rare case of cerebral venous hypertension in a 63-year-old male who showed venous reflux into the dural sinuses due to central venous stenosis on time-of-flight MR angiography. After management for central venous stenosis, the venous reflux disappeared.

• Journal of the Korean Society of Radiology
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• v.81 no.5
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• pp.1239-1245
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• 2020

Reversible cerebral vasoconstriction syndrome (RCVS) is a clinical and radiological syndrome with primary features that include hyperacute onset of severe headache and segmental vasoconstriction of the cerebral arteries, which resolve within 3 months. Vessel wall enhancement has been reported in some cases of RCVS; however, its pathophysiological and diagnostic implications remain unclear. We review a case of RCVS in a patient with transient vessel wall enhancement on contrast-enhanced fluid-attenuated inversion recovery images, focusing on the pathophysiological and diagnostic implications.

• Science of Emotion and Sensibility
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• v.15 no.4
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• pp.453-468
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• 2012

This study investigated the effects of Lavandula angustifolia (L. angustifolia) aroma on the brain electrical activity evaluated by an electroencephalogram (EEG) in the male adults since many researches were performed with females and few with males. Sleep quality of 35 male adults were analyzed by Pittsburgh sleep quality index, and they were divided into two groups of good sleep quality and poor sleep quality. EEG electrodes were attached at the frontal (F3, F4), temporal (T3, T4), occipital (O1, O2), and parietal (P3, P4) regions according to the International 10-20 system. EEG was measured for 3 min per each period of before, during, and after L. angustifolia aromatherapy. Subjects with good sleep quality showed increases in the delta power at the parietal region of both cerebral hemispheres and in the theta power at the temporal region of right hemisphere (p<0.05), and a decrease in the alpha at the parietal region of both cerebral hemispheres (p<0.05). And subjects with poor sleep quality showed increases in the delta power at the frontal region of left cerebral hemisphere and in the theta power at the frontal region of both hemispheres (p<0.05). It is concluded that L. angustifolia aroma has effects on decreasing an awakening status related-brain wave and increasing the sleep status related-brain waves in the male adults with good sleep quality, and has also effects on increasing the sleep status related-brain waves in the male adults with poor sleep quality.

• Applied Microscopy
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• v.29 no.4
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• pp.459-470
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• 1999

To investigate the changes during the differentiation of the cerebral neurons of the embryogenic day (ED) 9 and 10, investigated the ultrastructural changes in the cerebral neurons by Electromicroscope, also cerebral protein, the activity of dehydronases (LDH, MDH and SDH) and changes of adenosine triphosphate concentration were analyzed, the result obtained are as follows. In the ultrastructural changes in the cerebral neurons, chromatin in 9 day-old chick embryos are comparatively distributed to even in neucleoplasm and could investigate very prominently that nuclear membrane is double-layer. Esperially, Rough endoplasmic reticulum (RER) and Golgi complex are developed well, also polysome is investigated and synaptic vesicles were scattered. In 10 day-old chick embryos, chromatin evenly spread and nuclear membrane could be differentiated prominently. Rough endoplasmic reticulum (RER) contain cytoplasm, mitochondria and Golgi complex are comparatively developed well. In 9 day-old cultural group of chick embryo cerebrum were separated 37 polypeptide bands and In 10 day-old cultural group of chick embryo cerebrum were separated 38 poly -peptide bands. The more culture time increase, the more the activity of dehydronases (LDH, MDH and SDH) increase. LDH activity was 11.07 (9th day) and 12.12 (10th day), MDH activity was 11.89 (9th day) and 13.44 (10th day) and SDH activity was 8.45 (9th day) and 10.52 (10th day) respectively. The ATP concentration degreesed 10 day-old cultural group than 9 day-old cultural group.