• Proceedings of the KSMRM Conference
• /
• 1996.10a
• /
• pp.60-60
• /
• 1996

• Journal of the Korean Society of Radiology
• /
• v.7 no.5
• /
• pp.305-311
• /
• 2013

This study involves an experiment using functional magnetic resonance imaging(fMRI) to delineate brain activation for execution functional performance. Participates to this experiment of the normal adult (man 4, woman 6) of 10 people, is not inserts the metal all closed phobia and 24.5 year-old average ages which the operating surgeon experience which are not they were. The subject for a functional MRI experiment word -color test prosecuting attorney subject rightly at magnetic pole presentation time of 30 first editions and after presenting, uses SPM 99 programs and the image realignment, after executing a standardization (nomalization), a difference which the signal burglar considers the timely order as lattice does, pixel each image will count there probably is, in order to examine rest and active crossroad dividing independence sample t-test (p<.05). Overlapped in this standard anatomic image and got a brain activation image from level of significance 95%. With functional MRI resultant execution function inside being relation, the prefrontal lobe, anterior cingulate gyrus, parietal lobe, orbitofrontal gyrus, temporal lobe, parietal lobe was activated. The execution function promotes a recovery major role from occupational therapy, understanding about the damage mechanism is important. When confirms the brain active area which accomplishes an execution function brain plasticity develops the cognitive therapeutic method which is effective increases usefully very, will be used.

• Proceedings of the KSMRM Conference
• /
• 2001.11a
• /
• pp.101-101
• /
• 2001

목적： 침에 의한 진통 기전은 동양에서 경험이나 임상적으로 그 효능이 입증되어 왔으나 서양에서 요구하는 과학적인 접근 방법에 의한 증거가 매우 희박하며, 과학적인 접근이 매우 어려웠다. fMRI를 이용하여 뇌의 기능 영상을 관측함으로 그 증거를 제시하고자 한다. 대상 및 방법： 집게손가락에 특정시간동안 온도에 의한 자극을 주면서 기능적 뇌 영상을 받고 침 자극 전후의 활성 영역을 비교함으로써 침이 통증의 진통 기전에 효과가 있음을 보여 준다. 신뢰성 있는 데이터를 위해 여러 명의 영상을 평균하여 잡음을 제거하였다.

• Investigative Magnetic Resonance Imaging
• /
• v.3 no.1
• /
• pp.53-59
• /
• 1999

Purpose : To evaluate the usefulness of functional MR imaging (fMRI) for language mapping and determination of language lateralization. Materials and Methods : Functional maps of the language area were obtained during word generation tasks and decision task in ten volunteers (7 right handed, 3 left-handed). MR examinations were performed at 1.5T scanner with EPI BOLD technique. Each task consisted of three resting periods and two activation periods with each period of 30 seconds. Total acquisition time was 162 sec. SPM program was used for the postprocessing of images. Statistical comparisons were performed by using t-statistics on a pixel-by- pixel basis after global normalization by ANCOVA. Activation areas were topographically analyzed (p>0.001) and activated pixels in each hemisphere were compared quantitatively by lateralization index. Results : Significant activation signals were demonstrated in 9 of 10 volunteers. Activation signals were found in the premotor and motor cortices, the inferior frontal, inferior parietal, and mid-temporal lobes during stimulation tasks. In the right handed seven volunteers, activation of language areas was lateralized to the left side. Verb generation task produced stronger activation in the language areas and higher value of lateralization index than noun generation task or decision task. Conclusion : fMRI could be a useful non-invasive method for language mapping and determination of language dominance.

• Investigative Magnetic Resonance Imaging
• /
• v.12 no.2
• /
• pp.148-152
• /
• 2008

Purpose : To find the MR findings and evaluate the usefulness of MR in flexor hallucis longus(FHL) dysfunction. Materials and Methods : From 1992 to 2003, fourty patients were found to have surgically confirmed FHL dysfunction. 24 cases of 22 patients who had performed MR were included in this study. We analyzed the signal intensity of FHL tendon and muscle, tendon sheath, sheath effusion, and bone lesions, retrospectively. Results : Non-specific, increased sheath effusion of FHL tendon was seen in 12 cases (50%). Large amount of sheath effusion(grade 3) was observed in 5 cases (21%). The signal intensity of FHL tendon was normal in all cases. High signal intensity at the FHL muscle, proximal to musculotendinous junction was seen in 1 case (4%). One case (4%) of marrow edema of the talus and another one case (4%) of osteochondritis dissecans of the talus was seen. Conclusion : Non-specific, increased sheath effusion of FHL tendon was observed on MR in FHL dysfunction patients. Therefore, MR has a limited role in diagnosis of FHL dysfunction and is useful to exclude other bone and tendon diseases causing medial ankle pain.

• Proceedings of the KSMRM Conference
• /
• 2001.11a
• /
• pp.102-102
• /
• 2001

목적： 이중언어자에 있어서 각각의 언어가 대뇌에 어떻게 표상 되어 있는가에 대한 연구가 활발히 진행되고 있다. 본 연구에서는 한국어/중국어 이중언어화자를 대상으로 사용한 언어와 과제에 따라 활성화된 부위에 차이가 있는지 알아보고자 하였다. 대상 및 방법： 이중언어자(화교) 자원자 8명을 대상으로 하였고, 모두 오른손잡이였다. 한국어와 중국어로 구성된 어휘판단과제(lexical decision task)와 의미판단과제 (semantic decision task)를 이용하여 언어 영역의 활성화를 유도하였다. 어휘판단과제는 화면에 제시되는 두 자극이 모두 단어인지 아닌지 판단하여 신호하도록 하였고(예：원개 · 교화, 토끼, 지욱), 의미판단과제는 화면에 제시되는 두 자극의 의미가 관련 있는지 없는지 판단하여 신호하도록 하였다. (예：가가 ·제제, 아침·저녁). 대조과제는 아랍어(예：equation omitted) 글자의 크기를 판단하여 신호하도록 하였다. 1.5T 초전도 자기공명영상장치에서 EPI BOLD 기법을 이용하여 기능적 영상을 얻었으며 8명에서 얻은 영상을 정상화(normalize)한 후 SPM 프로그램을 이용하여 통계분석을 하였다. p<0.000001을 기준으로 얻어진 활성화 영상에서 각 언어와 과제별로 나타난 활성화 신호의 차이를 육안적으로 분석하였다.

• Journal of Science and Technology Studies
• /
• v.14 no.2
• /
• pp.199-222
• /
• 2014

Functional Magnetic Resonance Angiography (fMRA) was a technoscientific innovation that allows scientists to directly view the changes made in the blood vessels of a brain. fMRA was first developed at Neuroscience Research Institute (NRI) in Korea. fMRA mainly utilizes 7 Tesla MRI technology, and NRI is equipped with the instrument. First article on fMRA was published in 2008, and two more papers in 2010 and 2012 consecutively had been published on the newly developed technique. However, fMRA is a competitive technology with existing fMRI. Both techniques capture microvascular changes in a brain, and by doing it, both techniques visualize the cognitive and affective changes. fMRI technology was introduced by Seiji Ogawa in the early 1990's and has been widely used since then. In contrast, fMRA was a newer technology and rather unknown. Developers of fMRA in NRI used series of signifiant-politics in order to make it better known to scientific community as well as public. By resetting the boundaries of existing concept of fMRI, they tried to lower the threshold of a new concept/technique. This case study shows how technoscientists use semiotic strategies governing new technology.

• Progress in Medical Physics
• /
• v.15 no.3
• /
• pp.128-133
• /
• 2004

The fMRI response of the somatosensory cortex was investigated with vibrotactile stimulation. Three different frequencies of 8, 15, or 25 Hz were applied in order to mainly focus on the hemodynamic response of Meissner corpuscles sensitive to frequencies of 5-40 Hz. A closed-system, pneumatically-driven, rubber diaphragm was fabricated that overcame many of the limitations of existing vibrotactile devices and produced robust sensory cortex activation in an fMRI experiment. Increasing frequency vs. activation area was analyzed in terms of signal percent change and number of pixels. Our preliminary results indicated that the distribution of the signal percentage change widened and more activated pixels were obtained with higher frequencies.

• Investigative Magnetic Resonance Imaging
• /
• v.3 no.1
• /
• pp.47-52
• /
• 1999

Purpose : The purpose of this study was aimed to evaluate the BOLD(blood oxygen level dependent) contrast fMRI(functional MR imaging) in the occipital lobe and to compare with the metabolic changes based on H MRS (MR spectroscopy) and MRSI (MR spectroscopic imaging) before and after visual stimulation Materials and Methods : Healthy human volunteers (eight males and two females with 24-30 year age) participated in this study. All of the BOLD fMRI were acquired on a 1.5T MR with EPI during supervised visual stimulation in the occipital lobe. The red flicker with 8Hz was used for visual stimulation. After imaging acquisition, the MR images were transferred into unix workstation and processed with acquired from the same location based on the activation map. MRSI (magnetic resonance spectroscopic imaging) was also acquired to analyze the lactate changes before and after stimulation. Results : The activation maps were successfully produced by BOLD effect due to visual stimulation. NAA (N-acetyle aspartate)/Cr (creatine) ratio varied only from $1.79{\pm}0.28{\;}to{\;}1.88{\pm}0.20$ in activation area before and after stimulation. However, the signal intensity of lactate was elevated $9.48{\pm}4.38$ times higher than before activation. Lactate metabolite images were consistent with the activation maps. Conclusion : The BOLD contrast fMRI is enough sensitive to detect the activated area in human brain during the visual stimulation. Lactate metabolite map presents the evidence of lactate elevation on the same area of activation.

• Korean Journal of Cognitive Science
• /
• v.19 no.1
• /
• pp.75-88
• /
• 2008

Visual scene contains lots of redundant information. To process this redundant information without increasing brain's volume, human visual system may summarize incoming information. If similar but different information are given to visual system, visual system extracts statistical properties of the information. One example of the statistical representation is representation of mean size. The mean representation is accurate and durable. The process of mean representation is suggested to be parallel. However, previous studies on the mean representation mostly used behavioral methods. The purpose of this study was to investigate which neural regions extracted the mean size of a set of circles using fMRI method. According to previous studies, BOLD signal of certain areas that were in charge of cousin stimuli decreased when the same stimuli presented repetitively. We used this paradigm and found that BOLD signal of right occipital area was decreased when same mean site was presented repeatedly. This results suggest that right occipital area is the locus of mean representation of visual stimuli.