• Korean Journal of Biological Psychiatry
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• v.2 no.2
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• pp.275-280
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• 1995

Smooth pursuit eye movement, one of the reliable biological markers of schizophrenia, is not always abnormal in schizophrenic patients. Therefore the authors studied it in schizophrenic patients and normal controls and compared the results according to the presence or abscence of family history of psychosis and types (type I and type II). The results are as follows: 1) In the 18 normal control group (8 mole, 10 female), there was no sex difference in the responses of smooth pursuit eye movement. 2) In th 44 schizophrenic group (28 male, 16 female), there also was no sex difference in the responses of smooth pursuit eye movement. 3) In comparison of 44 schizophrenic group to 18 normal control group, there was significantly increased abnormal response in smooth pursuit eye movement in schizophrenic group (P < 0.005). 4) In schizophrenic group, there was no difference in the responses of smooth pursuit eye movement between type I and type II schizophrenia. 5) The presence or abscence of family history of psychosis made no difference in the responses of smooth pursuit eye movement in schizophrenic group. 6) Subdivision of type I or type II in each case of presence or abscence of family history made no difference in the responses of smooth pursuit eye movement in schizophrenic group.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.79-90
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• 2018

The purpose of this study was to investigate the difference of individuals with social anxiety tendency and normal people according to existence of emotional context in attention processing for positive facial stimulation. To do this, we investigated attentional processing for positive face stimuli in a condition without/with emotional context. SADS and CES-D were administered to 800 undergraduate students in D city and the social anxiety group (SA, n=24) and the normal control group (NC, n=24) were selected. In order to measure the two factors of attention process (attention engagement and attention disengagement), first gaze direction and first gaze time were measured through eye-movement tracking. The results show that the SA group exhibited faster attention disengagement from positive face stimuli compared to the NC group in the condition without context. But, when the positive context presented with positive face stimuli, there is no difference between SA and NC. This result suggests that the positive background affects emotional processing of social anxiety disorder.

• Korean Journal of Cognitive Science
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• v.32 no.1
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• pp.1-53
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• 2021

The aim of this study was to analyze word frequency effects on eye fixation duration in Korean reading with a one-boundary diffusion model and to show how these phenomena differ between adults (20-28yrs) and adolescents (13-14yrs). We predicted that the drift rate parameter in the boundary diffusion model would reflect the information processing of the fovea during silent reading. Through an eye movement tracking experiment while controlling word properties such as the word frequency and the age of acquisition, Experiment 1 and Experiment 2 show that the information processing pertaining to words to be placed in the fovea is connected to the drift rate of the one-boundary diffusion model parameters. In Experiment 1,in the adult group, the mean difference in the fixation time in the response proportion between the presence of high-frequency condition and low-frequency condition in the adult group was higher in quantile 0.9 than it was in the 0.1 quantile, but in the adolescent group, the mean difference in the fixation time in the response proportion between the two conditions was not significantly in the 0.9 quartile.In Experiment 2, the mean difference in the fixation time in the response proportion between early-acquired condition and late-acquired condition in both groups was also higher in the quantile 0.9 than in the 0.1 quantile. The distribution of the two conditions in the both groups was positively skewed, and the difference showed the same pattern found in the results of Ratcliff(Ratcliff & McKoon, 2008). Based on the experimental results, we propose one-boundary diffusion model as a tool to explain word property effects and individual differences in reading. In particular, we suggest that the drift rate parameter in the boundary diffusion model reflects the information processing of the fovea during reading. In addition, the results show that one-boundary diffusion model can be used to predict the aforementioned phenomena in reading.

• Korean Journal of Cognitive Science
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• v.25 no.3
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• pp.189-210
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• 2014

The present study investigated the perceptual span(or the span of effective vision) of junior-high school students during reading Korean, using the material and the moving-window display change technique used in Choi & Koh(2009). The 8 different window sizes were used in the experiment. They were 3, 5, 7, 9, 11, 13, 15 characters in size and the whole line. Reading rate, number of fixation, saccadic distance, fixation duration were compared between each window-size condition and the whole line condition. Considering the pattern of eye-movement measures above, the size of the perceptual span of junior-high school students in Korean reading may be estimated to be 9 characters, that is 4 characters to the right and 1 characters to the left of the fixation.

• Clinical and Experimental Pediatrics
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• v.50 no.3
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• pp.315-318
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• 2007

This report describes the long-term follow-up of a 10-year-old female patient with Joubert syndrome with short stature and brachydactyly. She presented with hyperpnea alternated with hypopnea, uncontrolled jerking eye movements, and hypotonia during early infancy. She was diagnosed with Joubert syndrome based on clinical symptoms and typical MRI findings at 5 months of age. Abnormal ventilation and eye movements disappeared at around 4 years of age. Head circumference kept within normal range for her age, but her height and weight growth were markedly retarded. Simple X-ray showed an enlarged skull with increased digital markings, hypoplasia of facial bones, and abnormal enchondral bone formations in hands and feet. This article is the first report of Joubert syndrome with peripheral dysostosis.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06b
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• pp.324-326
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• 2012

기계 학습에서 입력 데이터의 차원을 줄이는 문제(dimension reduction)는 매우 중요한 문제 중의 하나이다. 입력 변수의 차원이 늘어남에 따라 처리해야하는 연산의 수와 계산 복잡도가 급격히 늘어나기 때문이다. 이를 해결하기 위하여 다수의 기계 학습 알고리즘은 명시적으로 차원을 줄이거나(feature selection), 데이터에 약간의 연산을 가하여 차원이 작은 새로운 입력 데이터를 만든다(feature extraction). 반면 사람이 여러 종류의 고차원 센서 데이터를 입력받아 빠른 시간 안에 정확하게 정보를 처리할 수 있는 가장 큰 이유 중 하나는 실시간으로 판단하여 가장 필요한 정보에 집중하기 때문이다. 본 연구는 사람의 정보 처리 과정을 기계 학습 알고리즘에 반영하여, 집중도를 이용하여 효율적으로 데이터를 처리하는 방법을 제시한다. 이 성질을 시각 하이퍼네트워크 모델에 반영하여, 효율적으로 고차원 입력 데이터를 다루는 방법을 제안한다. 실험에서는 시각 하이퍼네트워크를 이용하여 고차원의 이미지 데이터에서 행동을 분류하였다.

• Korean Journal of Cognitive Science
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• v.31 no.2
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• pp.25-54
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• 2020

While there is no evidence for parafoveal processing in alphabetic languages such as English and Finnish, there is some evidence that morphological information is processed in syllabic languages like Chinese. Korean writing system, Hangul, would be able to provide morphological preview benefit effects since it is an "alphabetic syllabary" which contains both alphabetic and syllabic features. This study explored morphological parafoveal preview benefit effects during reading Korean using irregular verbs, which have phonological and orthographical differences between fundamental and conjugated forms. In the Experiment, the target word was irregular conjugated form, and there were four preview conditions: identical (e.g. 구워), fundamental form (e.g. 굽다), orthographically related (e.g. 굼다), and unrelated control (e.g. 죨어). In the result of study, identical was shortest and morphological, orthographical, unrelated preview were followed. Moreover, measures of first-pass reading of morphological preview were significantly shorter than those of unrelated control preview. This results support the hypothesis of morphological preview benefit effects in Korean. The implications of the results are discussed.

• Korean Journal of Cognitive Science
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• v.34 no.4
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• pp.315-347
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• 2023

This study aimed to investigate the semantic preview effect in the parafoveal processing of words that are presented in advance in the parafoveal area ahead of the fixation point, benefiting word processing in the fovea. Using the boundary technique in eye-tracking experiments, 25 Chinese-Korean bilinguals, whose native language is Chinese, were presented with 96 sentences that contained a mix of Chinese and Korean, where Korean words were associated with Chinese characters semantically. The study aimed to determine whether a semantic preview effect could be extracted in reading. The experimental sentences were divided into four conditions: the same Korean native word condition (e.g., "나라" meaning "country"), the same Korean word with semantic equivalent in Chinese condition (e.g., "국가" meaning "country"), the same Chinese condition with semantic equivalent in Korean (e.g., "国家" meaning "country"), and the unrelated Chinese condition to the target word (e.g., "围裙" meaning "apron"). The results showed a preview effect in both the Korean word and Chinese word conditions, with a larger preview effect observed in the Chinese word condition compared to the Korean word condition.

• Journal of The Korean Association For Science Education
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• v.34 no.8
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• pp.795-806
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• 2014

The purpose of this study is to develop an intervention program for improvement of elementary science-poor students' Basic Science Process Skill (BSPS) and to validate the intervention program's effectiveness using eye-tracker. The participants of this study were 35 elementary science-poor students. This study's method was the analysis of real-time eye movements during basic science process skill problem solving. SMI's 120 Hz iView XTM RED was used to collect EMD (eye movement data). Experiment 3.4 and BeGaze 3.4 programs were used to design experiment and to analyze EMD. The results of this study are as follows. First, we developed an intervention program including BSPS instructional strategy, behavior of teachers & student according instructional strategy stage, teachinglearning plan and learning note. Second, science poor students' BSPS ability has improved statistically significantly through the application of intervention program and BSPS problem-solving time decreased statistically significantly. Third, AFT (average fixation time) of BSPS Question and keyword area decreased statistically significantly. Fourth, APD (average pupil diameter) of BSPS problem-solving process expanded statistically significantly. Fifth, AST (average saccade time) of BSPS problem-solving process increased statistically significantly. Sixth, AFET (average fixation entry time) of BSPS problem-clue area was accelerated statistically significantly, AFT of BSPS problem-clue area reduced statistically significantly.

• Korean Journal of Cognitive Science
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• v.25 no.3
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• pp.211-232
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• 2014

People search a certain object or a person so many time in a day. Besides the information about what the target is, perceptual information of the target can influence on the search process. In the current study, using an eye-tracker we aimed to examine whether the perceptual information of previewing target stimuli on the visual search process of the target and the task performance. Participants had to identify the previewing target stimulus presented in the middle of the screen, and then had to search the target among 8 items presented in a circle array, and had to decide whether the size of the target in the search display was same as that of the previewing stimulus. The experimental conditions were divided into 8 within-subject conditions by whether the search display was consisted of all the same size items or different size items (homogeneous search display vs. inhomogeneous search display), by the size of the preview target stimulus, and by the size of the target stimulus in the search display. Research hypothesis is that the size information of the previewing influence on the visual search process of the target and task performance when the items in the search display are in different sizes. In the results of behavioral data analysis, the reaction time showed the main effect of the search display, and the size of the target stimulus in the search display. and the interaction between the size consistency effect of target stimulus and the search display condition. In the results of analysis of eye-movement information, the Initial Saccade to Target Ratio measurement showed the interaction between the size consistency effect of target stimulus and the search display condition as the reaction time measurement did. That is, the size consistency effect of target stimulus only in the inhomogeneous search display condition indicated that participants searched the items in the same size as that of preview target stimulus. Post-hoc analyses revealed that the search and task performance in the inhomogeneous display condition were faster when the target size was consistent, but rather slower when the target size was inconsistent.