• Korean Journal of Cognitive Science
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• v.13 no.1
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• pp.23-40
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• 2002

This study is to examine brain regions that are involved in picture encoding in normal adults using fMRI methods. In Scan 1, the picture encoding was studied during a semantic categorization task in comparison with word. In Scan 2 task type effects were studied both during a picture naming task and during a semantic categorization task with pictures. Subjects were asked to make decision either by pressing a mouse button (Scan 1) or by responding subvocally (naming or saying yes/no) (Scan 2). Regardless of stimulus type, left prefrontal, bilateral occipital, and parietal activations were observed during semantic processing in comparison with fixation baseline. Processing of word stimulus relative to picture resulted in activations in prefrontal and parieto-temporal regions in the left side while that of picture stimulus relative to word resultd in activations in bilateral extrastriatal visual cortices and parahippocampal regions. In spite of the same task demands, stimulus-specific information processings were involved and mediated by different neural substrates; the word encoding was associated with more semantic/lexical processings than pictures and the picture processing associated with more perceptual and novelty related information processings than word. Activations of dorsal part of inferior prefrontal region, i.e., Broca's areas were found both during the picture naming and during the semantic tasks subvocally performed Especially, during the picture naming task, greater occipital activations were found bilaterally relative to the semantic categorization task. indicating a possibility that greater and higher visual processing was involved in retrieving the name referred by picture stimuli.

• Korean Journal of Cognitive Science
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• v.25 no.2
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• pp.109-133
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• 2014

Psychological distance refers to the perceived gap between a stimulus and a person's direct experience and its activation influences the decisions and actions that the person makes towards the stimulus. We investigated whether the level of familiarity affects the construction of psychological distance. Specifically, we hypothesized that a familiar stimulus, relative to an unfamiliar stimulus, is perceived to be psychologically closer to the observer and so its perception might be modulated by the perceived spatial distance. The familiarity of stimuli was manipulated in terms of preexposure frequency and preexposure perceptual fluency. In experiments, participants were first exposed with three nonsense words in a lexical decision task. The nonsense words were presented in nonword trials with different levels of frequency (frequent vs. rare, Experiment 1) or with different levels of visibility (less blurred vs. more blurred, Experiment 2). Participants then performed a distance Stroop task with the most familiar and the least familiar nonwords. Each of them appeared in either proximal or distant spatial locations in scenes with clear depth cues. The results showed a significant interaction between the word familiarity and the spatial distance: the familiar word was judged faster in proximal locations but slower in distant locations relative to the unfamiliar word. The current findings suggest that metacognitive evaluation of familiarity could be one of the critical factors that underlie the construction of psychological distance.

• Science of Emotion and Sensibility
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• v.20 no.4
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• pp.41-54
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• 2017

Physical activity has positive effects on cognitive functions by aging. However, it is rare to find research that have scientifically investigated the effects on the affective-cognitive function. Thus, this study aims to brain-scientifically research its effects of physical activity on the affective-cognitive function of adults in adolescence and senescence. As subjects of this study, a total of 60 males adults in D region were selected, and then equally divided into four groups of young exercise group(25~35y/o), young non-exercise group(26~35y/o), old exercise group(60~70y/o), and old non-exercise group(60~70y/o). As experiment tools, the EEG measuring equipment and International Affective Picture System(IAPS) were used. The experiment of this study used an affective-cognitive task where subjects pressed a button depending on emotional valence(positive, neutral, negative) shown in the pictures. During the task, EEG measured eight areas(Fp1, Fp2, Fz, C3, C4, Cz, T3, T4) out of brain areas in accordance with the international 10-20 electrode system, EEG was measured. For statistical analysis, a three-way ANOVA on $4(group){\times}3(stimulus){\times}8(area)$ was conducted. The results showed main effects of group in both reaction time and accuracy, and also in the latency of P3. And there was an interaction between group and stimulus the amplitude of P3. In conclusion, Physical activity has positive effects on the affective-cognitive function of people in adolescence and senescence.

• Research in Mathematical Education
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• v.3 no.2
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• pp.99-112
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• 1999

In this paper, we represent the Piagetian reversible thinking by using the concept of fuzzy complements. In this case the turning point to the reversible thinking can be corre-sponded to the equilibrium points of a fuzzy set, which are shown through some examples. On the other hand, Piaget considered disequilibrium in the theory of equi-libration as a stimulus for students' cognitive structure, furthermore as the driving forces behind intellectual growth. But we suggest a di erent application o Piagetian equi-librium in another point of view as a tool understanding students' psychological stability in problem solving activity.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2002.05a
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• pp.105-110
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• 2002

The syllable and the morpheme are known to be important linguistic variables. This study examined whether these variables were activated in an early stage of word recognition using the fast priming task. Mixing the lettercase for the prime, the results of experiment 1 and 2 revealed effects of the syllable and the morpheme at a short SOA (Stimulus Onset Asynchrony), but not at a long SOA. Using the same manipulation in the experiment 3 and 4, an effect of syllable was found to be significant at the short SOA, but not at the long SOA. The study showed that the syllable plays a role in an early stage of word recognition.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.1
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• pp.15-25
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• 2020

Prevalence of pediatric obesity has increased worldwide in the last 20 years. Obese children suffer not only physical complications but also mental health problems such as depression, attention deficit hyperactivity disorder (ADHD), and eating disorders, as well as psychosocial impairments, such as school adjustment problems, bullying, and low self-esteem. Recently, there have been some studies on the association of mental health problems and pediatric obesity. In the treatment of pediatric obesity, many previous studies suggest multidisciplinary treatment. However, cognitive behavioral therapy (CBT) has attracted attention because obese children are accompanied by body image distortion, emotion dysregulation, and difficulties in stimulus control. This review is a narrative summary of the recent studies on mental health problems and CBT in pediatric obesity. The relationship between depression/anxiety and pediatric obesity is still inconsistent but recent studies have revealed a bidirectional relation between depression and obesity. Additionally, some studies suggest that obese children may have eating disorder symptoms, like loss of control eating, and require therapeutic intervention for pediatric obesity treatment. Furthermore, impulsivity and inattention of ADHD symptom is thought to increase the risk of obesity. It has also been suggested that CBT can be very effective for mental health problems such as depression, impulsivity, and body image distortion, that may coexist with pediatric obesity, and use of multimedia and application can be useful in CBT.

• Asian Journal for Public Opinion Research
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• v.1 no.2
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• pp.90-102
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• 2014

By integrating useful insights from social cognitive theory and social capital theory, we aim to develop a model for better understanding people's behaviors related to the use of social networking sites (SNSs) and formalize the role of social capital in individuals' continuous SNS use. Propositions that emphasize the triadic interactive relationships among environmental, personal, and behavioral factors were highlighted in this study. After reviewing previous studies, in this paper we proposed the following: (1) the causation between SNS use and individuals' perceived social capital might be mutual; social capital may not only be the result of media selectivity, but could also be an essential stimulus initiating the start of using SNSs; (2) the influences of SNSs use on the generation of individuals' online social capital might be conditional upon particular patterns of use; (3) both the level of dependence on SNSs and the differentiated patterns of SNSs use vary according to individuals' perceived offline social capital and their personal characteristics, for instance, personality or self-construal, and social anxiety.

• Korean Journal of Cognitive Science
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• v.35 no.1
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• pp.49-95
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• 2024

Polygraph examination, statement validity analysis and P300-based concealed information test are major three examination tools, which are use to determine a person's truthfulness and credibility in criminal procedure. Although polygraph examination is most common in criminal procedure, but it has little admissibility of evidence due to the weakness of scientific basis. In 1990s to support the weakness of scientific basis about polygraph, Farwell and Donchin proposed the P300-based concealed information test technique. The P300-based concealed information test has two strong points. First, the P300-based concealed information test is easy to conduct with polygraph. Second, the P300-based concealed information test has plentiful scientific basis. Nevertheless, the utilization of P300-based concealed information test is infrequent, because of the quantity of probe stimulus. The probe stimulus contains closed information that is relevant to the crime or other investigated situation. In tradition P300-based concealed information test protocol, three or more probe stimuli are necessarily needed. But it is hard to acquire three or more probe stimuli, because most of the crime relevant information is opened in investigative situation. In addition, P300-based concealed information test uses oddball paradigm, and oddball paradigm makes imbalance between the number of probe and irrelevant stimulus. Thus, there is a possibility that the unbalanced number of probe and irrelevant stimulus caused systematic underestimation of P300 amplitude of irrelevant stimuli. To overcome the these two limitation of P300-based concealed information test, one-probe P300-based concealed information test protocol is explored with various machine learning algorithms. According to this study, parameters of the modified one-probe protocol are as follows. In the condition of female and male face stimuli, the duration of stimuli are encouraged 400ms, the repetition of stimuli are encouraged 60 times, the analysis method of P300 amplitude is encouraged peak to peak method, the cut-off of guilty condition is encouraged 90% and the cut-off of innocent condition is encouraged 30%. In the condition of two-syllable word stimulus, the duration of stimulus is encouraged 300ms, the repetition of stimulus is encouraged 60 times, the analysis method of P300 amplitude is encouraged peak to peak method, the cut-off of guilty condition is encouraged 90% and the cut-off of innocent condition is encouraged 30%. It was also conformed that the logistic regression (LR), linear discriminant analysis (LDA), K Neighbors (KNN) algorithms were probable methods for analysis of P300 amplitude. The one-probe P300-based concealed information test with machine learning protocol is helpful to increase utilization of P300-based concealed information test, and supports to determine a person's truthfulness and credibility with the polygraph examination in criminal procedure.

• Korean Journal of Cognitive Science
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• v.6 no.1
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• pp.47-71
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• 1995

A psychological disturbance caused by letters in double image was termed as'letter sickness'.The effects of stimulus exposure time and letter familiarity on the letter sickness were measured to test a hypothesis that disturbances in eye movement and recognition stages is the cause of letter sickness.Letter sickness incteased significantly as stimulus exposure time lengthened from 50ms,100ms,to 3000ms.It was also significantly higher with familiar Hangul letters as compared with less familiar foreign letters and meaningless words as compared with meaningful words,respectively.These experimental findings imply that letter sickness is caused by the failure of adjusting eye movements to dismiss the double images.that the more familiar the letters.the more strongly the letter-identification process is commotted,resulting in the increased effect of disturbance from double image.and that the disturbance effect of double image is amplified when it is hard to extract the meaning from familiar letters.An experiment where subjects were made to learn Braille-like symbols consisting of 6 dots to test the hypothesis that the stronger the tendency to process the meaning of a symbol,the stronger becomes letter sickness due to double image,also showed that letter sickness significantly increased as a function of learning.

• Korean Journal of Cognitive Science
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• v.5 no.2
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• pp.25-45
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• 1994

The presnt study investigated the effect of stimulus-response compatibility (S-R compatibility) on Hangul transcription typing. In this experiment, two condition were manipulated, the first was a low S-R compatibility condition in which consonants were typed with left hand and vowels with right hand; the second was a high S-R compatibility condition in which hands for consonants and vowels were reversed. Subjects were requested to type the letter presented on the screen as accurately and immediately as possible. It was found that the compatibility interacted with the vowel shape. That is, in the high S-R compatibility condition, the response time was shorter when letters of vertically- shaped vowel were typed than when those of horizontally-shaped vowel were typed. In the low S-R compatibility codition, however, the response time was shorter for letters of horizontally-shaped vowel than for those of vertically-shaped vowel.