• Clinical and Experimental Pediatrics
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• v.55 no.2
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• pp.63-67
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• 2012

A 4-year-old girl with Panayiotopoulos syndrome presented with a history of 4 prolonged autonomic seizures. The clinical features of her seizures included, in order of occurrence, blank staring, pallor, vomiting, hemi-clonic movement on the right side, and unresponsiveness. A brain magnetic resonance imaging (MRI) showed a slightly high $T_2$ signal in the left hippocampus. Interictal electoencephalogram revealed spikes in the occipital area of the left hemisphere. We analyzed the current-source distribution of the spikes to examine the relationship between the current source and the high $T_2$ signal. The current source of the occipital spikes was not only distributed in the occipital area of both cerebral hemispheres, but also extended to the posterior temporal area of the left hemisphere. These findings suggest that the left temporal lobe may be one of the hyperexcitable areas and form part of the epileptogenic area in this patient. We hypothesized that the high $T_2$ signal in the left hippocampus of our patient may not have been an incidental lesion, but instead may be related to the underlying electroclinical diagnosis of Panayiotopoulos syndrome, and particularly seizure. This notion is important because an abnormal $T_2$ signal in the hippocampus may represent an acute stage of hippocampal injury, although there is no previous report of hippocampal pathology in Panayiotopoulos syndrome. Therefore, long-term observation and serial follow-up MRIs may be needed to confirm the clinical significance of the $T_2$ signal change in the hippocampus of this patient.

• Korean Journal of Cognitive Science
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• v.24 no.1
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• pp.49-69
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• 2013

While we interact with other people or objects, the brain continuously updates our own body schema to recognize the agent of observed actions. The Extrastriate Body Area (EBA) provides an initial interface for the sense of agency by integrating visual inputs of body parts with internal signals related to self-generated body movements. Less is known, however, about how the functional use of tools contributes to such processes. Here, we investigated whether tool-specific affordance would differentially affect the neural responses in the EBA depending on the agency of imaginary actions. In each trial we presented a picture of an object in a rectangular frame. Objects were either the tools typically brought towards the body (body tools; e.g., telescope, earphones) or away from the body (world tools; e.g., pen, dice; Rueschemeyer, Pfeiffer, & Bekkering, 2010). Depending on the color of the frame, participants imagined either themselves or the other person using the tool (self vs. other conditions). These four types of trials were randomly intermixed with blank trials. As results, independently localized right EBA regions of interest showed greater activation when participants imagined themselves using body tools than using world tools whereas no such differential activations were found when they imagined the other person using the tools. The postscan test revealed no significant difference in vividness of imagery between the self and other conditions. Our results suggest that the EBA incorporates functional affordance of tools into the body schema in order to enhance the sense of agency and to guide our own actions.

• Korean Journal of Radiology
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• v.23 no.4
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• pp.446-454
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• 2022

Objective: To evaluate whether hyperoxia-induced ΔR₁ (hyperO₂ΔR₁) can accurately identify histological infarction in an acute cerebral stroke model. Materials and Methods: In 18 rats, MRI parameters, including hyperO₂ΔR₁, apparent diffusion coefficient (ADC), cerebral blood flow and volume, and ¹⁸F-fluorodeoxyglucose uptake on PET were measured 2.5, 4.5, and 6.5 hours after a 60-minutes occlusion of the right middle cerebral artery. Histological examination of the brain was performed immediately following the imaging studies. MRI and PET images were co-registered with digitized histological images. The ipsilateral hemisphere was divided into histological infarct (histological cell death), non-infarct ischemic (no cell death but ADC decrease), and nonischemic (no cell death or ADC decrease) areas for comparisons of imaging parameters. The levels of hyperO₂ΔR₁ and ADC were measured voxel-wise from the infarct core to the non-ischemic region. The correlation between areas of hyperO₂ΔR₁-derived infarction and histological cell death was evaluated. Results: HyperO₂ΔR₁ increased only in the infarct area (p ≤ 0.046) compared to the other areas. ADC decreased stepwise from non-ischemic to infarct areas (p = 0.002 at all time points). The other parameters did not show consistent differences among the three areas across the three time points. HyperO₂ΔR₁ sharply declined from the core to the border of the infarct areas, whereas there was no change within the non-infarct areas. A hyperO₂ΔR₁ value of 0.04 s^-1 was considered the criterion to identify histological infarction. ADC increased gradually from the infarct core to the periphery, without a pronounced difference at the border between the infarct and non-infarct areas. Areas of hyperO₂ΔR₁ higher than 0.04 s^-1 on MRI were strongly positively correlated with histological cell death (r = 0.862; p < 0.001). Conclusion: HyperO₂ΔR₁ may be used as an accurate and early (2.5 hours after onset) indicator of histological infarction in acute stroke.

• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.35-46
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• 1996

Dopamine transporter concentrations have been known to decrease in Parkinson's disease (PD) or increase in Tourette's disorder. The purpose of this study was to evaluate the effectiveness of [I-123]N-(3-iodopropene-2-yl)-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-chlorophenyl) tropane (IPT) as an imaging agent for measuring changes in transporter concentrations with PD. IPT labelled with 6.69+/-0.64 mCi(247.53+/-23.68 MBq) of I-123 was intravenously injected into ten patients(age: 55+/-11) with PD, and six normal controls(NC)(age: 46+/-14) as a bolus. Dynamic SPECT scans of the brain were then performed for 5 minutes each over 120 minutes on a triple headed camera. Time activity curves were generated for the left basal ganglia(LBG), right basal ganglia(RBC), and occipital cortex(OCC). The statistical parameters included the time to peak activity, the contrast ratio of LBG and RBG to OCC at several time points, and the accumulated specific binding counts/mCi/pixel(ASBC) from 0 to 115 minutes. The uptake of IPT in the brains of PD and NC peaked within 10 minutes of injection in all subjects. The maximum target to background ratio in the basal ganglia of PD and NC occurred at 85+/-20 min and 110+/-6 min of injection, respectively. The BG/OCC ratios at 115 minutes for PD and NC were 2.15+/-0.54 and 4.26+/-0.73, respectively. The ASBC at 115 minutes for PD and NC were 152.91+/-50.09 and 289.51+/-49.00, respectively. The ratio of BG/OCC for the NC was significantly higher than the ratio for PD. SPECT data matched with clinical diagnosis for PDs. The ratio between BG and OCC and the ASBC for PD were clearly separated from NC and may be useful outcome measures for clinical diagnosis. The findings suggest that IPT may be a very useful tracer for early diagnosis of PD and study of dopamine reuptake site.

• Korean Journal of Cognitive Science
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• v.22 no.3
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• pp.255-270
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• 2011

The purpose of this study was to examine the effects of nonspecific and specific cue on decision making during situation awareness. Participants were 36 male college students who were randomly assigned to one of three groups: (1) nonspecific situation awareness, (2) specific situation awareness, and (3) a control group. Every participant was in the level 3-4.5 according to American National Tennis Level Program. Participants were asked to watch tennis single defence, single offence, double defence rally and when the screen stops, they were required to push the button(left, middle, or right) appropriate for the ball's direction to return as soon as possible. The experiment was designed to be analyzed for group(3)${\times}$condition(3)${\times}$area(7) using three-way ANOVA. The dependent variables were reaction time, accuracy rate, and amplitude and latency of P300. The result showed that the latency of the nonspecific situation awareness group and the specific situation awareness group was shorter and their amplitudes were higher than the control group. Fz, Cz, Pz were prominent among areas, and the single defence condition was more prominent than the single offence and the double defence condition. As a result of the study, it can be suggested that the information about situation awareness provided beforehand directly affects the brain's information processing. In addition, it shows that ERP can be a useful index for studying situation awareness.

• Clinical and Experimental Pediatrics
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• v.50 no.6
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• pp.588-591
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• 2007

Left ventricular thrombus is mainly caused by anterior myocardial infarction or severe cardiac wall dysfunction of the apex, and is rarely caused by a complication of acute myocarditis. A 12-year-old female who developed symptoms of motor dysphasia and incomplete hemiparesis of the right side was admitted to the hospital. The brain MRI taken on the day of her admission showed acute cerebral infarction in the left basal ganglia and the frontoparietal lobe. The echocardiogram showed a movable thrombus, which was $19{\times}28mm$ sized and located in the apex of the left ventricle. So in order to prevent further thromboembolic event we performed open cardiac surgery via the atrium and removed the thrombus of the left ventricle. After the removal of the thrombus her symptoms improved and she was discharged from the hospital. Thrombus formation in acute viral myocarditis are considered to be related with endocardial injury and blood flow stasis. Treatment with anticoagulants in left ventricular thrombosis may not be effective and may even cause a major thromboembolism. When the thrombus is laminar and fixed, one should consider anticoagulant therapy. But if the thrombus is pedunculated and movable, which means that there are higher possibilities of major embolism or there may be already one, one should consider surgical removal. We report a 12-year-old girl who required surgical removal of a left ventricular thrombus caused by acute viral myocarditis.

• Korean Journal of Biological Psychiatry
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• v.10 no.2
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• pp.168-176
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• 2003

Objectives:We investigated the characteristics of P300 generators in obsessive-compulsive disorder(OCD) patients by using voxel-based statistical parametric mapping of current density images. Methods:P300 generators, produced by a rare target tone of 1500Hz under a frequent non-target tone of 1,000Hz, were measured in 15 right-handed OCD patients and 15 controls. Low Resolution Electromagnetic Tomography(LORETA), using a realistic head model of the boundary element method based on individual MRI, was applied to the 128-channel EEG. Statistical parametric mapping(SPM) was applied for the statistical analysis. Results:We found that both groups had the mean current density of P300 in the parietal, temporal and prefrontal lobe. There was a trend for decreased current density in the prefrontal area in OCD patients. The statistical comparison showed current density increase in the supraparietal area, a statistically significant longer P300 latency and a trend for reduced P300 amplitude in OCD patients. Conclusion:It suggests that P300 source of both groups exists in multiple brain regions at the same time. And both groups had no statistically significant differences in the current density of P300 except for increased current density in the supraparietal area in OCD patients. But, considering the statistically significant longer P300 latency, a trend for reduced P300 amplitude and relative mean current density reduction in the prefrontal area in OCD patients, this study suggests that the frontal lobe may have a reduced normal inhibitory process in OCD patients.

• The Journal of the Korea Contents Association
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• v.14 no.7
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• pp.281-290
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• 2014

This study is a quasi-experimental research using non-equivalent control group pre-post design in order to understand the effectiveness of biomedical ethics education using movies. This study selected the first-year 45 students and 63 students who were attending at two 4-year-course nursing colleges as an experimental group and control group, respectively. Then, this study provided the experimental group with the lecture on biomedical ethics for 16 weeks using the movie related to the ethical issues covering 10 areas. Data collection was done for 5 days from August 26, 2013 until December 5, 2013, and conducted pre-post questionnaire survey on the 1st week session and 16th session after explaining there search purpose and getting a written agreement from the subjects. As a result of analysis of the collected data using SPSS Statistics 18, it was found that students' average point of biomedical ethics awareness improved to 3.31 from 3.07; additionally, in the analysis of the data by sub-area, the point in artificial abortion improved to 3.69 from 3.08; artificial insemination from 2.99 to 3.57; fetal diagnosis from 3.10 to 3.45; a newborn's right to life from 3.39 to 3.55 and organ transplant from 3.26 to 3.53, respectively(P<.001). On the contrary, the research results showed that there was no change in the point of the mercy-killing, brain death, and human biotechnology areas, respectively(p>.05). Conclusively, movie-aided education could be diversely used for nursing education provided movie contents should be in accord with a lecture subject in a way that can arouse students' interest and concern, and improve educational satisfaction.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.286-294
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• 2010

This study was performed to identify the cerebral network associated with sensation through the tickling stimulation, which is distinctive from the rest of other networks processing normal stimulation and to investigate the difference of laughing mechanism which is closely related to tickling using functional MRI(fMRI). A 16 healthy volunteers (mean age: 28.9) on a 3.0T MR scanner during two sensation conditions. Counterbalanced stimulus were presented across the participants, and the stimulation was used block design. Acquired data was analyzed by the statistical parametric mapping (SPM 99). Subject and group analysis was performed. Individual analysis showed the activation of somatic sensation area in both tasks and the tickling sensation test showed more activated area in the Wernicke's area(BA40) compared to the normal sensation. The group analysis result shows that under normal stimulations, both sides of somatosensory cortices(BA 1,2 and 3) were activated and under tickling stimulation, not only the cortices but also those huge activation on thalamus, cingulate gyrus and insular lobe were detected. When the tickling was stopped, significant activations were shown in right cingulate gyrus, left MFG area and left insular lobe. A cerebral area responsible for recognizing tickling sensation was examined and the primitive stimulation such as tickling is much closely related to laugh, which is an important factor for various social activities.

• Korean Journal of Biological Psychiatry
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• v.25 no.3
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• pp.60-71
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• 2018

Objectives A growing body of evidence has suggested that morphologic changes in cerebellum may be implicated with pathophysiology of major depressive disorder (MDD). The aim of this study is to investigate a difference in the volume and cortical thickness of the specific region of cerebellum between patients with MDD and healthy controls (HC). Methods A total of 127 patients with MDD and 105 HC participated in this study and underwent T1-weighted structural magnetic resonance imaging. We analyzed volume and cortical thickness of each twelve cerebellum regions divided by left and right and the volume and cortical thickness of the whole cerebellum from T1-weigted image of participants. One-way analysis of covariance was used to investigate the volume and cortical thickness difference of total and specific regions between two groups adjusting for age, gender, medication, and total intracranial cavity volume. Results We found that the patients with MDD had significantly greater volume in the left cerebellum lobule III region [false discovery rate (FDR)-corrected p = 0.034] compared to HC. Also, our findings indicate that cortical thickness of left lobule VIIB (FDR-corrected p = 0.032) and lobule VIIIB (FDR-corrected p = 0.032) are significantly thinner in the patients with MDD compared with the HC. No significant volume and cortical thickness differences were observed in other sub-regions of the cerebellum. The volumes and cortical thickness of whole cerebellum between patients with MDD and HC did not differ significantly. Conclusions We observed the region-specific volume and cortical thickness difference in cerebellum between the patients with MDD and HC. The results of our study implicate that the information about structural alterations in cerebellum with further replicative studies might provide a stepping stone toward a specific marker to diagnose MDD.