• Korean Journal of Cognitive Science
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• v.14 no.4
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• pp.1-7
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• 2003

The common features of the behavioral inhibition and the action monitoring that are considered as one of the executive functions were investigated using event-related brain potentials (ERPs) and source localization analysis. The electrophysiological correlates of behavioral inhibition and action monitoring ate analyzed when the subjects performed the Go/NoGo task. Two ERP components of behavioral inhibition termed as N200 and P300 in NoGo condition were differ from those of Go condition, that is the amplitudes of NoGo N200 and P300 are largest on the fronto-central region, which may reflect the inhibitory control of frontal lobe required in NoGo condition. The error-related negativity (ERN) observed on the fronto-central region when the subjects committed error was much larger in amplitude and faster in latency than those of the correct-related negativity (CRN), which may indicate that the signal of action monitoring is much more required for the error response. The correlation analysis for the ERP components of behavioral inhibition and action monitoring revealed the significant negative correlation among the latencies of NoGo N200 and P300 and the amplitude of ERN, which may reflects that the faster subjects inhibit response, the more monitor their own action. The close relationship between behavioral inhibition and action monitoring was also supported by the results of source localization analysis, which showed the common neural sources of NoGo N200 and ERN was anterior cingulate cortex.

• Pediatric Infection and Vaccine
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• v.15 no.1
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• pp.30-35
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• 2008

Purpose : We evaluated clinical presentations of brain abscesses, including predisposing factors, causative organisms, and mortality rate in neonates and children. Methods : We retrospectively reviewed the medical charts of neonates and children with brain abscesses treated at Severance Hospital from January 1997 through December 2006. Results : Among 27 neonates and children with brain abscesses, overall mortality was 22 % and 38% of survivors developed neurologic sequelae. The mortality rate was 38% in 8 infants with brain abscesses. The most common location of brain abscesses were frontal and parietal lobes, followed by temporal lobe. There were 7 cases with multiple brain abscesses. Streptococci (33%), Staphylococci (27%), and Gram-negative enterics (20%) were commonly isolated. The common predisposing conditions were neurosurgical procedure (30 %), cyanotic congenital heart disease (15%), and sinusitis/otitis (7%). Fever (74%), headache (37%), nausea/vomiting (33%), and altered mental status (33%) occurred commonly. Compared with children older than 1 year of age, infants were associated with multiple brain abscesses (63%, P=0.011) and high rates of death or neurologic sequelae (88%, P= 0.033). Conclusion : We should have a high index of suspicion in order to recognize the condition as early as possible, especially in infancy with brain abscesses who presents vague or nonspecific symptoms and signs.

• Korean Journal of Cognitive Science
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• v.11 no.3_4
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• pp.33-43
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• 2000

The distinction between short-term store (STS) and long-term store (LTS) has been made in the perspective of information processing. Memory system theorists have argued that memory could be conceived as multiple memory systems beyond the concept of a single LTS. Popular memory system models are Schacter & Tulving (994)'s multiple memory systems and Squire (987)'s the taxonomy of long-term memory. Those m models agree that amnesic patients have intact STS but impaired LTS and have preserved implicit memory. However. there is a debate about the nature of the long-term memory impairment. One model considers amnesic deficit as a selective episodic memory impairment. whereas the other sees the deficits as both episodic and semantic memory impairment. At present, it remains unclear that episodic memory should be distinguished from semantic memory in terms of retrieval operation. The distinction between declarative memory and nondeclarative memory would be the alternative way to reflect explicit memory and implicit memory. The research focused on the function of frontal lobe might give clues to the debate about the nature of LTS.

• Journal of Chest Surgery
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• v.35 no.3
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• pp.231-234
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• 2002

Moyamoya disease is an unusual cerebrovascular disorder characterized by occlusive intimal dysplasia of the distal internal carotid and proximal cerebral arteries as well as other collateral arteries. However, moyamoya diseases are recently being reported as a systemic process. We experienced one case of coronary artery occlusive disease affected by moyamoya disease. The patient was a 35-year-old female, experiencing intermittent NYHA class ll dyspnea and exertional chest pain for 6 months and right paresthesia for 1 month before admission. Cerebral artery angiogram showed abnormal cerebrovascular systems and confirmed moyamoya disease with cerebral infarction of the left frontal lobe. In coronary artery angiogram, left coronary artery was not visualized due to total occlusion of the left main ostium and left coronary blood flow was supplied from normal right coronary artery. CABG was performed with OPCAB. Both internal mammary arteries were used for LAD and LCx. Intraoperative coronary artery findings showed intimal hyperplasia and no definite thrombi, and nondiseased coronary arteries were good and patent. We concluded that this patient's coronary artery disease was affected by moyamoya disease, and moyamoya disease should be evaluated in the extracerebral cardiovascular system.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.1
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• pp.3-11
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• 2003

Attention-deficit/Hyperactivity disorder(ADHD) is the most common psychiatric disorder of childhood and among the most prevalent chronic health conditions affecting school-aged children. Children with ADHD experience significant functional problems, such as school difficulties, academic underachievement, troublesome interpersonal relationships with family members and peers, and low self-esteem. The most widely used pharmacological treatments for ADHD are psychostimulants, such as methylphenidate and amphetamine salts. These medications provide clinical efficacy by increasing the availability of catecholamines, primarily dopamine, in the frontal lobe of the brain. immediate-release(IR) formulations of sychostimulants were among the most effective psychotrophic medications in the psychopharmacological treatment. However, there are some limitations of IR formulations：the short half-life and duration of efficacy, which result in the need for multiple daily dosing and the poor compliance. These limitations have led to the development of once-daily, extended-release(ER) formulations of methylphenidate and amphetamine salts. However, these ER formulations may not be as immediately helpful to ADHD children due to delayed onset of action and the acute tolerance which is the failure to sustain the efficacy with the same concentration of drug as the initial stage of medication. OROS-methylphenidate(Concerta$^{\circledR}$) given once a day produces an ascending-pattern plasma drug level generated by the osmotically released, timed drug-delivery system. These new formulations of the psychostimulants have been shown to be a useful alternative to old stimulant medications through the evidence by the clinical trials.

• Tuberculosis and Respiratory Diseases
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• v.42 no.4
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• pp.618-623
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• 1995

Cryptococcosis is a systemic mycosis that most often involves the lungs and central nervous system and, less frequently, the skin, skeletal system, and prostate gland. Cryptococcus neoformans, the causative organism, is a yeastlike round or oval fungus, 4 to $6{\mu}m$ in diameter, which is surrounded by a polysaccharide capsule and reproduces by budding and found in soil and other environmental areas, especially those contaminated by pigeon droppings. Humans and animals acquire infection after inhalation of aerosolized spores. Condition or factors that predispose to cryptococcosis include corticosteroid therapy, lymphoreticular malignancies, HIV infection, and sarcoidosis etc. We discribed a case of cryptococcosis involving lung and CNS coincidently without specific underlying disease and the literature on subject were reviewed. A fifty-six year-old previously healthy female presented with headache of 3 months of duration. She had no history suggesting immunologic suppression and we could not find any abnormal laboratory findings including blood sugar, serum immunoglobulin and complement level, HIV antibody, and T cell subsets. Chest roentgenogram and CT scan showed a solitary soft tissue mass in LUL with distal pneumonitis. Brain MRI showed granulomatous lesion in cerebellum and parasagittal cortex of right frontal lobe. The diagnosis was made by bronchoscopic brushing cytology, transthoracic fine needle aspiration, and sputum KOH mount and culture. She was treated 6 weeks course of Amphotericin B and switched to oral fluconazole therapy for 3 months. Her symptoms and X-ray findings were improved gradually and she is now under regular clinical follow up.

• Journal of Biomedical Engineering Research
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• v.24 no.4
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• pp.241-246
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• 2003

To evaluate the usefulness if functional MR imaging(MRI) for the determination of language dominance system and to assess differences in the visual and auditory instrument language generation task according to activation task or activated area. Functional maps of the language area were obtained during visual and auditory instructions in word generation tasks in 6 healthy volunteer with right-handness were examined on a 1.5T scanner and the EPI BOLD technique, and three pulse sequence technique get of the true axial planes. Both task consisted of 96 phases including 6 activations and rests contents. Postprocessing were done on MRDx program by using cross correlation method. Two task compare the blain activation area surveyed of 1anguage lateralization index. To evaluated of the detection rates of Broca. Wernicke, pre-frontal lobe, Supplementary Motor Area (SMA) and pre-motor cortex areas and the differences of language lateraliaztion among two word generation task To lateralization index survey in 1anguage area on right and left in brain get to activation area pixel in brain. Compared to visual and auditory instrument task in the language areas get to the lateralization index. Two language generation task high detection rates of Broca and Wernicke areas. The visual instruction no detected in the auditory area, and auditory instruction no detected in the visual area. There was statistics significant different of them among language generation task. 1'his indicated that language area obtained image of the brain functional MR imaging usefulness in the visual and auditory task instrument.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup1
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• pp.25-29
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• 2001

Objective : Intracranial metastasis is responsible for nearly 50% of mortalities of systemic cancers. Although its frequency is increasing and there is little doubt that improving the quality and expectancy of life is the final goal, the mode of treatment is still disputed. The authors report the postoperative motor function after surgery in patients with metastatic tumors around the motor cortex. Materials and Methods : We studied 24 patients with metastatic tumors around the central sulcus during the last 22 months. Motor function was assessed pre- and post-operatively as well as its response to corticosteroids. MRI, neuronavigation system and intraoperative ultrasonography were used for tumor localization and functional MRI and cortical stimulator were used to define the motor cortex. Results : Single metastasis was found in 13 cases(54%) and 11 cases(44%) had multiple foci. Thirteen cases were located in precentral, 7 in postcentral, and 4 in superior or middle-frontal lobe. The most common primary focus was the lung(16 cases). There was no difference in postoperative motor function improvement between the steroid responsive group and non-responsive group(92% versus 90%). Ninty-two percent of the patients showed significant improvement of motor function and lived independently but there was worsening in the upper extremity in one and in another no improvement. Whole brain radiation of 3000cGy was given in all cases and 4 patients died of recurrence in primary or intracranial focus during mean follow-up periods of 14 monthes. Conclusion : Surgery may provide substantial improvement of the motor function and quality of life of the patients with metastatic tumors around the motor cortex.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.2
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• pp.157-164
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• 2016

Objectives : The objective of this study was to investigate the characteristics of language profiles according to whether or not Korean children with autism spectrum disorder(ASD) also have ADHD, and to examine the relationship with executive function. Methods : Participants in the study were boys with ADHD aged 6 to 11 years who visited the clinic from January 2012 to December 2013. In this study, 25 boys with ASD were included, and completed scales included the Korean version of Autism Diagnostic Interview-Revised(K-ADI-R), Korean version of Autism Diagnostic Observation Schedule(K-ADOS), Korean ADHD Rating Scale(K-ARS), and Korean-Conners' Parent Rating Scale(K-CPRS). They also completed neuropsychological tests and assessed language profiles. Patients were categorized into two groups(with ADHD and without ADHD). T-test and Multivariate analysis of covariance (MANCOVA) was used for analysis. Results : Statistically, no difference was found in receptive and expressive language ability between the ASD groups with and without ADHD. However, a lower score in Test of Problem solving(TOPS) was observed for ASD with ADHD than for ASD without ADHD, with problem solving and finding cues showing significant differences. Conclusions : These findings suggest that language profiles in the ASD group without ADHD could be similar to those in the ASD group with ADHD, but comorbid ADHD could lead to more difficulty in linguistic ability for problem solving and could be related with executive function of the frontal lobe.

• Journal of the Korean Society of Radiology
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• v.16 no.6
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• pp.761-769
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• 2022

Pads with high dielectric materials have been used in a variety of applications to locally improve the field sensitivity and homogeneity of RF pulses in clinical MRI studies. In this study, we aimed to improve such pads in consideration of the practical problems associated with the application of actual clinical images. A high permittivity pad to increase the attenuated B1 field strength was fabricated and tested in 7T MRI. Sim4Life simulation and experimental results show stronger and relatively uniform B1 near field. In order to improve the image quality in the whole cerebellum, known as a region with low sensitivity, a guide was made to reduce the mechanical change of the pad. In order to improve the wearing comfort, the pad was designed by dividing it into upper and lower parts. The facial pad showed an overall signal increase effect in areas such as the turbinate in the nasal cavity. Signal increase was expected in areas such as the frontal lobe and eyes, but the effect was either insignificant or it was difficult to see the effect in the imaging protocol. In conclusion, this paper showed a cerebellar-optimized pad with an improved nasal signal while maintaining its effectiveness.