• The Korean Journal of Nuclear Medicine
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• v.35 no.4
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• pp.231-240
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• 2001

Purpose: Normal aging results in detectable changes in the brain structure and function. We evaluated the changes of regional cerebral glucose metabolism in the normal aging process with FDG PET. Materials and Methods: Brain PET images were obtained in 44 healthy volunteers (age range 20-69 'y'; M:F = 29:15) who had no history of neuropsychiatric disorders. On 6 representative transaxial images, ROIs were drawn in the cortical and subcortical areas. Regional FDG uptake was normalized using whole brain uptake to adjust for the injection dose and correct for nonspecific declines of glucose metabolism affecting all brain areas equally. Results: In the prefrontal, temporoparietal and primary sensorimotor cortex, the normalized FDG uptake (NFU) reached a peak in subjects in their 30s. The NFU in the prefrontal and primary sensorimotor cortex declined with age after 30s at a rate of 3.15%/decade and 1.93%/decade, respectively. However, the NFU in the temporoparietal cortex did not change significantly with age after 30s. The anterior (prefrontal) posterior (temporoparietal) gradient peaked in subjects in their 30s and declined with age thereafter at a rate of 2.35%/decade. The NFU in the caudate nucleus was decreased with age after 20s at a rate of 2.39%/decade. On the primary visual cortex, putamen, and thalamus, the NFU values did not change significantly throughout the ages covered. These patterns were not significantly different between right and left cerebral hemispheres. Of interest was that the NFU in the left cerebellar cortex was increased with age after 20s at a rate of 2.86%/decade. Conclusion: These data demonstrate regional variation of the age-related changes in the cerebral glucose metabolism, with the most prominent age-related decline of metabolism in the prefrontal cortex. The increase in the cerebellar metabolism with age might reflect a process of neuronal plasticity associated with aging.

• 대한약리학회:학술대회논문집
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• 2006.10a
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• pp.116.2-116.2
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• 2006

• Animal cells and systems
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• v.8
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• pp.14-14
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• 2004

• Journal of the Korean Magnetic Resonance Society
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• v.10 no.2
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• pp.126-140
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• 2006

Purpose: Contrary to the human study, it has rarely investigated metabolic alterations in the dorsolateral prefrontal cortex (DLPFC) of depressed rats versus age and sex-matched controls using proton magnetic resonance spectroscopy (MRS). Thus, the purpose of this research was to verify the feasibility of metabolic differences between the normal rat and the depression model rat. Materials and Methods: A homogeneous group of 20 SD male rats was used for MRI and in vivo 1H MRS. To induce a depressed status in SD rats, we performed the forced swimming test (FST). Using image-guide, water suppressed in vivo 1H MRS with 4.7 T MRI/MRS system, NAA/Cr and Cho/Cr ratios were mainly measured between depressed rats and normal subjects. Results: In depressed rats, increased Cho/Cr ratio was measured versus control subjects. However, no significant group effect for NAA/Cr was observed between case-control pairs. Discussion and Conclusions: The present 1H MRS study shows significant brain metabolic alterations of dorsolateral prefrontal cortex with experimental depressed status of SD rat induced by FST compared to normal subjects. This result provides new evidence that in vivo 1 H MRS may be a useful modality for detecting localized functional neurochemical markers alterations in left DLPFC in SD rats.

• Korean Journal of Biological Psychiatry
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• v.3 no.1
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• pp.115-120
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• 1996

To investigate characteristic drug effects on the genetic basis, the authors administered haloperidol- the $D_2$ antagonist- and clozapine -the atypical antipsychotics with few extra- pyramidal side effects- to the rats. Then, we edobtain brain specimen from the striatum, prefrontal cortex, and cortical region and compared the degree of c-fos expression. The results are 1) haloperidol was found to produce a rapid and transient induction of dos mRNA expression in striatum as compared with cortex and prefrontal area. 2) clozapine was found to produce rapid induction of c-fos mRNA in striatum and prefrontal area. From these data, we can concluded that the mechanism of action of haloperidol is different from the mechanism of clozapine in gene expression.

• Korean Journal of Biological Psychiatry
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• v.4 no.1
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• pp.19-23
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• 1997

Attention is a phenomenon hard to define, but can be conceptualized as a mental function ranging from sustaining readiness to perceive stimuli to understanding the nature and value and selecting stimuli that are most relevant to the given situation. Manifestations of attention include vigilance, and focused, directed, selective, divided, and sustained attentions. While basic attentional tone is controlled by the interaction among reticular activating system, thalamus and prefrontal cortex, direction and selection of attention is controlled by neural circuits of prefrontal, posterior parietal, and limbic cortex. It is expected that understanding of attention and its neural control could provide answers to the relationship between pathophysiology and clinical symptoms of some major psychiatric disorders. More efforts are required to develop tools to assess more detailed and various aspects of attention in Korea.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.138-143
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• 2001

본 연구에서는 생환공간에서의 음향감성을 평가하기 위하여 긍정감성을 유발하는 음환경으로서 '명상음악'과 부정감성을 유발하는 음환경으로서 '헬리콥터소음'과 '마루가 삐거덕거리는 소음'을 제시하였을 때 행동활성화체계(BAS)와 행동억제체계(BIS)의 민감성이 서로 다른 집단들을 대상으로 전전두엽의(PFC) 비대칭성과 심장박동율변동성(HRV)을 분석하였다. 연구결과, 명상음악을 청취시에는 안정상태에 비하여 좌측전두엽이 더 활성화되고 HRV의 LF/HF는 감소된 반면에 소음환경에서는 우측전두엽이 더 활성화되고 LF/HF는 더 증가하였다.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.780-783
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• 2007

A Many studies have been made on the prediction of human voluntary movement intention in real-time based on invasive or non-invasive methods to help severely motor-disabled persons by offering some abilities of motor controls and communications. In the present study, we have developed an internet game driven by and/or linked to a brain-computer interface (BCI) system. Activities of two single neuronal units recorded from either hippocampus or prefrontal cortex of SD rats were used in real time to control two-dimensional movements of a robot, or a game object.

• 대한약리학회:학술대회논문집
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• 2006.10a
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• pp.106.2-106.2
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• 2006

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.6
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• pp.517-527
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• 2020

Layer 2/3 pyramidal neurons (L2/3 PyNs) of the cortex extend their basal dendrites near the soma and as apical dendritic tufts in layer 1, which mainly receive feedforward and feedback inputs, respectively. It is suggested that neuromodulators such as serotonin and acetylcholine may regulate the information flow between brain structures depending on the brain state. However, little is known about the dendritic compartment-specific induction of synaptic transmission in single PyNs. Here, we studied layer-specific serotonergic and cholinergic induction of long-term synaptic plasticity in L2/3 PyNs of the agranular insular cortex, a lateral component of the orbitofrontal cortex. Using FM1-43 dye unloading, we verified that local electrical stimulation to layers 1 (L1) and 3 (L3) activated axon terminals mostly located in L1 and perisomatic area (L2/3). Independent and AMPA receptor-mediated excitatory postsynaptic potential was evoked by local electrical stimulation of either L1 or L3. Application of serotonin (5-HT, 10 μM) induced activity-dependent longterm depression (LTD) in L2/3 but not in L1 inputs. LTD induced by 5-HT was blocked by the 5-HT₂ receptor antagonist ketanserin, an NMDA receptor antagonist and by intracellular Ca²⁺ chelation. The 5-HT₂ receptor agonist α-me-5-HT mimicked the LTD induced by 5-HT. However, the application of carbachol induced muscarinic receptor-dependent LTD in both inputs. The differential layer-specific induction of LTD by neuromodulators might play an important role in information processing mechanism of the prefrontal cortex.