• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 1부
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• pp.728-732
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• 2008

본 연구는 운동 표상에 관한 뇌 메커니즘의 이해를 위해 fMRI를 이용한 측정 시스템을 개발하였다. 개발된 시스템의 검증을 위해 예비 실험을 시행하였다. fMRI task는 visual feedback을 제공하는 task와 차단하는 task 두 가지의 task로 구성되었다. 실험 결과 visual feedback이 제공되었을 때는 left superior orbital gyrus, bilateral precentral gyrus, left superior occipital gyrus, left supplementary motor area, right thalamus, right postcentral gyrus 그리고 right superior parietal lobule 같은 영역들이 활성화 되었다. Visual feedback이 차단되었을 때는 left precuneus, right middle temporal gyrus, bilateral supplementary motor area, right anterior cingulate cortex, left Inferior temporal gyrus, left insula lobe, right superior parietal lobule, bilateral postcentral gyrus 그리고 left precentral gyrus 같은 영역들이 활성화 되었다. 개발된 시스템을 통해서 visual feedback이 차단되었을 경우 운동 표상에 관한 뇌 메커니즘을 알아 볼 수 있었다.

• Journal of Korean Neurosurgical Society
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• 제30권4호
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• pp.456-462
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• 2001

Objective : Although cingulotomy has been applied to patients with affective disorders more frequently, there are numerous reports of its use for the control of severe pain. The goal of this study was to investigate the role of stereotactic bilateral anterior cingulotomy for intractable cancer pain. Method : Between January and June, 2000, we underwent stereotactic bilateral anterior cingulotomy in 6 patients for intractable cancer pain with poor response to opioids. The patients were suffering from widespread musculoskeletal or visceral pain. We made four lesions along the two tracks on either side of the cingulate cortex. Result : In all patients, pain reliefs after cingulotomy were dramatic and immediate. Five out of six patients did not require any opioids and one patient could reduce dose of opioids. There were no deaths or serious complications related to the procedure. Conclusion : These results suggested that a bilateral anterior cingulotomy might be useful method to control intractable cancer pain associated with the widespread metastatic disease. To provide rationale of bilateral anterior cingulotomy in intractable cancer pain, the theoretical mechanisms and role of bilateral anterior cingulotomy are discussed, along with our surgical techniques and the course of our patients.

• 생물정신의학
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• 제15권2호
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• pp.110-117
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• 2008

Objectives : Posttraumatic stress disorder(PTSD) has been primarily associated with emotional problems. Recently, however, the impact of PTSD on cognitive processes has interested a growing number of researchers. The current study is aimed at investigating the cognitive aspects of PTSD at both behavioral and neurological levels. Methods : We recruited individuals with PTSD who survived the Daegu subway explosion in 2003 as well as non-PTSD individuals as a control group. To evaluate the inhibitory processes and the neural mechanisms, we had these individuals perform the negative priming task simultaneously with functional MRI scanning. Results : Behaviorally, the negative priming effect was intact in the control group but was not evident in the PTSD group. In the imaging results, only the PTSD group showed the negative priming effect (i.e., increased activation of the negative priming condition as opposed to the neutral condition) in the dorsolateral prefrontal cortex, anterior cingulate cortex, and inferior temporal gyrus. The PTSD group also showed increased activity for the positive priming condition as opposed to the neutral condition in the claustrum. These results confirm and extend the previous findings that the integrity of the ACC is compromised in the trauma survivors due to disrupted white matter tract. Conclusions : The current results suggest that deteriorated performance of the PTSD group may be due to the functional problem as well as the structural abnormalities.

• The Journal of Korean Physical Therapy
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• 제15권3호
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• pp.295-345
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• 2003

This study investigated activation of cerebral cortex in patients with hemiplegia that was caused by neural damage. Key-point control movement therapy of Bobath was performed for 9 weeks in 3 subjects with hemiplegia and fMRI was used to compare and analyze activated degree of cerebral cortex in these subjects. fMRI was conducted using the blood oxygen level-dependent(BOLD) technique at 3.0T MR scanner with a standard head coil. The motor activation task consisted of finger flexion-extension exercise in six cycles(one half-cycles = 8 scans = $3\;sec{\times}\;8\;=\;24\;sec$). Subjects performed this task according to visual stimulus that sign of right hand or left hand twinkled(500ms on, 500ms off). After mapping activation of cerebral motor cortex on hand motor function, below results were obtained. 1. Activation decreased in primary motor area, whereas it increased in supplementary motor area and visual association area(p<.001). 2. Activation was observed in bilateral medial frontal gyrus, middle frontal gyrus of left cerebrum, inferior frontal gyrus, inter-hemispheric, fusiform gyrus of right cerebrum, superior parietal lobule of parietal lobe and precuneus in subjedt 1, parahippocampal gyrus of limbic lobe and cingulate gyrus in subject 2, and inferior frontal gyrus of right frontal lobe, middle frontal gyrus, and inferior parietal lobule of left cerebrum in subject 3 (p<.001). 3. Activation cluster extended in declive of right cellebellum posterior lobe in subject 1, culmen of anterior lobe and declive of posterior lobe in subject 2, and dentate gyrus of anterior lobe, culmen and tuber of posterior lobe in subject 3 (p<.001). In conclusion, these data showed that Key-point control movement therapy of Bobath after stroke affect cerebral cortex activation by increasing efficiency of cortical networks. Therefore mapping of brain neural network activation is useful for plasticity and reorganization of cerebral cortex and cortico-spinal tract of motor recovery mechanisms after stroke.

• 생물정신의학
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• 제22권3호
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• pp.109-112
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• 2015

Since the early 2000s, there has been a continued interest in lie detection using functional magnetic resonance imaging (fMRI) in neuroscience and forensic sciences, as well as in newly emerging fields including neuroethics and neurolaw. Related fMRI studies have revealed converging evidence that brain regions including the prefrontal cortex, anterior cingulate cortex, parietal cortex, and anterior insula are associated with deceptive behavior. However, fMRI-based lie detection has thus far not been generally accepted as evidence in court, as methodological shortcomings, generalizability issues, and ethical and legal concerns are yet to be resolved. In the present review, we aim to illustrate these achievements and limitations of fMRI-based lie detection.

• Korean Journal of Radiology
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• 제2권2호
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• pp.68-74
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• 2001

Objective: To describe the brain CT and MR imaging findings of unusual acute encephalitis involving the thalamus. Materials and Methods: We retrospectively reviewed the medical records and CT and/or MR imaging findings of six patients with acute encephalitis involving the thalamus. CT (n=6) and MR imaging (n=6) were performed during the acute and/or convalescent stage of the illness. Results: Brain CT showed brain swelling (n=2), low attenuation of both thalami (n=1) or normal findings (n=3). Initial MR imaging indicated that in all patients the thalamus was involved either bilaterally (n=5) or unilaterally (n=1). Lesions were also present in the midbrain (n=5), medial temporal lobe (n=4), pons (n=3), both hippocampi (n=3) the insular cortex (n=2), medulla (n=2), lateral temporal lobe cortex (n=1), both cingulate gyri (n=1), both basal ganglia (n=1), and the left hemispheric cortex (n=1). Conclusion: These CT or MR imaging findings of acute encephalitis of unknown etiology were similar to a combination of those of Japanese encephalitis and herpes simplex encephalitis. In order to document the specific causative agents which lead to the appearance of these imaging features, further investigation is required.

• 대한불안의학회지
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• 제10권1호
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• pp.44-51
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• 2014

Objective : The amygdala has been considered to be a critical region in the pathophysiology of social anxiety disorder, but subregional connectivity pattern has not been examined yet despite lots of previous functional neuroimaging studies. Methods : Resting-state functional magnetic resonance imaging data was obtained in 19 patients with social anxiety disorder and 20 normal controls, and default mode functional connectivity with each of basolateral, centromedial and superficial areas of the amygdala was measured and compared between the two groups. Results : Differential amygdala-based networks between the two groups were distributed to all over the brain. In particular, however, a bias on the amygdala-cingulate pathway was observed in the superficial amygdala only. Connectivity strengths between the superficial amygdala and perigenual anterior cingulate cortex were correlated with scores of social interaction and avoidance. Conclusion : Our findings provide new insights into understanding of the intrinsic cognitive bias model of social anxiety disorder. An abnormality in superficial amygdala-anterior cingulate connectivity may influence on cognitive processing of socially-relevant information in social anxiety disorder.

• 대한핵의학회지
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• 제32권3호
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• pp.238-249
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• 1998

목적: PET을 이용하여 특정한 자극에 대한 국소 뇌혈류 변화를 영상화함으로써 비침습적으로 뇌의기능적 구조를 밝혀 낼 수 있다. 이 연구에서는 대조과제와 언어성 및 시각적 작업기억중추에 대한 활성화과제를 수행하면서 뇌혈류 PET을 시행하고 그 차이를 분석하여 작업기억에 관한 뇌기능지도를 구성하였다. 대상 및 방법: 정상인 6명에 대해서 각각 대조과제, 단어기억 언어성 작업기억 활성화과제, 그림기억 언어성 작업기억 활성화과제, 시각적 작업기억 활성화과제를 수행시키면서 뇌혈류 PET을 촬영하였다. 언어성 작업기억과제로서 단어 기억과제에서는 4개의 단어를 순차적으로 보여주고 1초 후 1개의 단어를 보여주어 동일한 단어가 4개의 단어 중에 있었으면 버튼을 누르게 하며 $H_2^{15}O$ PET을 촬영하였다. 두 번 째 언어성 작업기억과제인 그림 기억과제에서는 단어 대신에 특정 단어가 연상되는 사물의 그림을 보여 주었다. 시각적 작업기억과제로는 사람의 얼굴 사진을 보여 주고 같은 실험을 하였다. 의미 없는 기호를 보여 주면서 특정한 기호가 나오면 버튼을 누르게 함으로써 시각적 자극과 손가락운동으로 인한 뇌혈류 분포를 포함하게 하여 대조과제로 삼았다. SPM96소프트웨어를 이용하여 각 영상을 표준 지도 위에 공간적으로 정규화하고 활성화상태에서 뇌혈류가 의미 있게 증가된 영역을 찾아내기 위하여 각 화소의 방사능 계수에 대한 공분산분석을 하여 전체 계수 차이를 제거한 후 국소 계수 차이에 대한 귀무가설을 검증하여 각 화소의 Z 값에 대한 통계적 파라메터 영상(statistical parametric image)으로 뇌기능지도를 작성하였다. 결과: 단어를 이용한 언어성 작업기억에 대한 뇌기능지도에서는 왼쪽 브로카 영역와 전-운동영역, 왼쪽 소뇌, 오른쪽 대상회에서 뇌혈류가 증가하였다. 그림 기억과제 때에는 단어 기억과제에서 활성화된 각 부위에 더하여 왼쪽 위쪽 측두엽, 왼쪽 기저핵과 시상, 왼쪽 전-전두엽 등에서 뇌혈류가 증가하였다. 얼굴기억과제는 오른쪽 아래쪽 전두엽, 브로카 영역, 대상회, 위쪽 두정엽 등 주로 오른쪽 대뇌반구의 뇌혈류가 증가하였다. 세 가지 실험에 공통적으로 활성화된 영역을 찾기 위한 결합분석에는 왼쪽 전-운동영역, 소뇌와 기저핵, 오른쪽 대상회, 브로카 영역, 기저핵에서 뇌혈류가 증가하였다. 결론: 이상의 결과는 언어성 작업기억은 주로 왼쪽 대뇌반구의, 시각적 작업기억은 주로 오른쪽 대뇌반구의 활동에 의해서 주도되며 작업기억에 공통적인 활성화지역이 있다는 가설을 지지하였다. 전두엽이 작업기억에 중요한 역할을 한다고 생각한다.

• Journal of Korean Neurosurgical Society
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• 제29권6호
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• pp.815-821
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• 2000

Parasplenial arteriovenous malformations(AVMs) are rare vascular malformations which have distinct clinical and anatomical features. They are situated at the confluence of the hippocampus, isthmus of the cingulate gyrus and the gyrus occipitotemporalis medialis. These lesions are anterior to the calcarine sulcus and their apex extends towards the medial surface of the trigonum. Posterolaterally, these lesions are in close proximity to the visual cortex and optic radiation. The objectives in the surgery of parasplenial AVMs are complete resection of the lesions and preservation of vision. These objectives must be achieved with comprehensive understanding of the following anatomical features :1) the deep central location of the lesions within eloquent brain tissue ; 2) the lack of cortical representation of the AVMs that requires retraction of visual cortex ; 3) deep arterial supply ; 4) deep venous drainage ; 5) juxtaposition to the choroid plexus with which arterial supply and venous drainage are shared. A 16-year-old female student presented with intraventricular hemorrhage from a right parasplenial-subtrigonal AVM. The lesion, fed by posterior cerebral artery and drained into the vein of Galen, was successfully treated by the inter-hemispheric parietooccipital approach. To avoid visual field defect a small incision was made on precuneus anterior to the calcarine sulcus. In this report, the authors describe a surgical approach with special consideration on preservation of visual field.

• 생물정신의학
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• 제28권2호
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• pp.36-49
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• 2021

Suicide is a leading cause of death worldwide, especially among adolescents and young adults. Considering this fact, it is imperative that we understand the neural mechanisms underlying suicidal thoughts and behaviors in youth from a neurodevelopmental perspective. In this review, we focused on the magnetic resonance imaging studies that examined the neural correlates of suicidal ideations (SI) or attempts (SA) in youth. We reviewed twenty-three cross-sectional studies reporting the structural and functional alterations in association with SI or SA among adolescents and young adults with various mental disorders. The previous literature suggests that the dorsolateral prefrontal cortex, anterior cingulate cortex, and ventral frontolimbic circuit, may play an important role in the pathophysiology of suicidal behavior in youth through altered top-down control over emotion and impulsivity. Future studies with a longitudinal design and using multimodal imaging techniques may be of help to identify novel therapeutic targets specific for youth with suicidal thoughts and behaviors.