• Korean Journal of Cognitive Science
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• v.11 no.3_4
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• pp.83-93
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• 2000

The effect of immediate and delayed recognition memory on event-related potential (ERP) was studied using a continuous recognition memory task and event-related potential (ERP). Among 240 stimulus words 40 words were not repeated. 100 were immediately repeated and 100 were repeated after 5 intervening words. All words presented only once during the experiment were referred to as new words. Subjects responded faster and more accurately to words repeated immediately than to new words a and to those repeated after intervening words. In terms of ERP results the immediately repeated words were associated with large P300 amplitude, early P300 latency and a absence of N400. while words repeated after a delay were associated with small P300 a amplitude. late P300 latency and the presence of N400. N400 was elicited only to new w words and to those repeated after a delay. The general morphology of the waveform was s similar for three stimulus-presentation conditions until around 3l0ms after the onset of stimulus. These results indicate that immediate and delayed recognition memory could be dissociated into two distinct processes possibly being mediated by different cerebral mechanism, and the dissociation between two types of recognition memory emerges around 3l0ms poststim'ulus. The immediate and delayed recognition memory for words are considered in terms of template matching and memory searching.

• Korean Journal of Forensic Psychology
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• v.12 no.2
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• pp.99-120
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• 2021

This study examined the differences in facial emotion processing related to psychopathic traits. On the basis of the Psychopathic Personality Inventory-Revised (Lee & Park, 2008), students were divided into psychopathic trait (n=15) and control (n=15) groups. Participants performed two tasks consisted of negative(angry, fear, sad) and neutral faces. Event-related potentials(EPRs) were recorded when participants categorized gender in the implicit task and emotion in the explicit task. We analyzed the late positive potentials(LPP) amplitude to investigate differences in emotion processing between psychopathic trait group and control group. In the implicit task, there was no significant difference in both groups. However, there was a significant interaction between emotion and group at the frontocentral region in the explicit task. The psychopathic trait group showed greater LPP amplitudes for the neutral faces than for the negative faces, whereas the control group showed similar LPP amplitudes for the neutral and negative faces at the frontocentral site. These results might reflect the abnormalities in emotional processing in individuals with psychopathic traits.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.242-250
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• 2016

This study was conducted to investigate whether Stroop-related cognitive task will be affected according to the preceding affective valence factored by matchedness in response time(RT) and whether facial recognition will be indexed by specific event-related potentials(ERPs) signature in normal person as in patients suffering from affective disorder. ERPs primed by subliminal(30ms) facial stimuli were recorded when presented with four pairs of affect(positive or negative) and cognitive task(matched or mismatched) to get ERP effects(N2 and P300) in terms of its amplitude and peak latency variations. Behavioral response analysis based on RTs confirmed that subliminal affective stimuli primed the target processing in all affective condition except for the neutral stimulus. Additional results for the ERPs performed in the negative affect with mismatched condition reached significance of emotional-face specificity named N2 showing more amplitude and delayed peak latency compared to the positive counterpart. Furthermore the condition shows more positive amplitude and earlier peak latency of P300 effect denoting cognitive closure than the corresponding positive affect condition. These results are suggested to reflect that negative affect stimulus in subliminal level is automatically inhibited such that this effect had influence on accelerating detection of the affect and facilitating response allowing adequate reallocation of attentional resources. The functional and cognitive significance with these findings was implied in terms of subliminal effect and affect-related recognition modulating the cognitive tasks.

• 한국HCI학회:학술대회논문집
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• 2007.02b
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• pp.608-611
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• 2007

본 연구는 가상환경에서 위반행동을 한 사람에게 그 행동에 관한 단서를 제시하였을 때 나타나는 심리 생리적 변화를 측정하고자 한다. 피험자는 가상환경에서 주어진 시나리오에 따라 목적지까지 자동차를 운전하는 역할을 수행한다. 시나리오는 운전을 하는 도중에 사고를 내고 차량을 수리하는 내용으로 구성하였다. 피험자는 위반, 관찰, 통제집단의 세 집단으로 선별되며, 위반집단은 고의적으로 교통사고를 일으키게 된다. 위반 행동을 한 피험자에게 사건에 관련된 질문을 컴퓨터로 제시하고 동시에 뇌파를 측정한다. 사건 관련 질문은 위반행동과 관련이 있는 장소, 차량, 행동에 대한 답변보기들로 구성되었으며 피험자에게는 위반행동과 무관한 보기답안과 함께 제시된다. 측정결과, 위반행동과 무관한 보기답안 보다 위반행동과 관련된 보기답안에서 높은 뇌파 반응이 나타났다. 따라서 이를 이용하여 위반행동을 탐지하는 것이 가능할 것으로 보인다. 연구 확장을 통해 가상환경으로 실제 위반 상황을 재구성하여 적용하는 것도 유용해 보인다.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.22 no.2
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• pp.63-71
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• 2004

제품에 대한 사용자의 주관적인 느낌을 파악하고 감성적 만족도를 측정하기 위해서는 주로설문지 등을 이용한 심물리적 스케일(Psychophysical scales) 방법이 주로 이용되어 왔다(Han et al., 2000). 그러나 사용자에게 주관적인 선호도를 점수로 표현하게 하는 심물리적 평가 방법은 몇 가지 문제점을 가지고 있다.

• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.36-46
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• 1994

The event-related potentials are difined as the changes in voltage that occur at paticular time before, during and after something that happens in the physical world or some psychological processes. The possibilities of clinical applications of ERP are considered because the endogenous potentials such as P3 and contingent negative variation(CNV) are determined by the psychological significance of the stimulus. The P3 is a positive wave that occurs when a subject detects an informative task-relevant stimulus. The P3 amplitude and latency are affected by the various factors as subjective probabilites, stimulus meaning and information transmission. It is suggested that P3 wave is associated with the decision making, cognitive or perceptual closure, memory updating and transfer of information to consciousness etc. Although the intracerebral origin of the P3 wave is not known, the P3 may have multiple intracerebral generators. The CNV is a slow potential shift occuring during the foreperiod, between warning and response signals, in a reaction time experiment. It is related to expectancy, preparation etc. The abnormal findings of P3 wave and CNV in various psychiatric disorders are also discussed.

• Journal of the Korean Home Economics Association
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• v.49 no.2
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• pp.37-49
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• 2011

The present study investigated the semantic and syntactic processes in Korean children's sentence comprehension by measuring event-related brain potentials(ERPs). The subjects were 18 right-handed, healthy native Korean children(1st graders), who were free from any hearing problems. While the children listened to the auditory sentence stimuli, ERPs were recorded with the electrodes mounted in a 'Quik-Cap' on the subject's head. The ERP data were recorded and analyzed using the NeuroScan 4.3 and EEGLABv6.03b programs. For statistical analyses, descriptive statistics, three-way repeated measures ANOVA, and t-tests were performed using a SPSS 15.0 PC program. The results indicated that semantic violations elicited a negativity (N400) ranging from 300 to 500 msec. For syntactic violations, children displayed a positivity (P600) ranging from 900 to 1,100 msec. The discovery of N400 and P600 in semantic and syntactic processes respectively, confirmed the suggestion that Indo-European and Korean languages share a common mechanism for sentence comprehension.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.7 no.2
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• pp.179-189
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• 1996

Objective : This study was conducted to find out the electrophysiological abnormalities of the patients with attention-deficit/hyperactivity disorder(abbr. ADHD) through identifying the profiles of the event-related potentials. Methods : Through measuring event-related potentials of 20 patients with ADHD and 16 normal control children using Oddball paradigm, we evaluated the latencies and amplitudes of each wave form. Results : In the group older than 9 years old, the latencies that reflect selective attention and discriminative capacity of the patients with ADHD were significantly longer than those of normal controls, which suggests that patients with ADHD be more distractible to non-significant stimuli and that they be in lark of sustained attention and discriminative ability. Conclusions : We concluded that the patients with ADHD are more distractible to trivial stimuli than normal children but they lack discriminative, sustained ability of attention.

• Korean Journal of Cognitive Science
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• v.20 no.2
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• pp.155-181
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• 2009

Psychophysiologists are often interested in the EEG signals that accompany certain psychological events. When one is interested in a time series of event-related changes in EEG, one focuses on examining how the waveforms recorded at individual electrode sites vary over time across one or more experimental conditions. This is an analysis of event-related potentials (ERPs). In addition to such a classical EEG analysis in the time domain, the EEG measures can be investigated in the frequency domain. Moreover, it has been demonstrated that spectral analyses can often yield significant insight into the functional cognitive correlations of the signals. Therefore, this review paper tries to summarize essential concepts (e.g. phase-locking) and conventional methods (e.g. wavelet transformation) for understanding spectral analyses of brain oscillatory activity. Phase-coherence is also introduced in relation to functional connectivity of the brain.

• Korean Journal of Cognitive Science
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• v.33 no.2
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• pp.95-107
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• 2022

Facial processing of different racial origin has been investigated at various levels including perceptual, emotional, and socio-cultural processing. Particularly, a good deal of studies have been conducted to show "other race effect (ORE)" to indicate that subtle facial information such as identity or emotional expressions are often under-processed in racial out-group members. However, few studies have investigated whether attentional modulation toward racial out-group faces could explain ORE. We investigated whether novelty-driven attentional mechanism is involved in face perception using event-related potential (ERP). Twenty-two Korean (KR) and nine Caucasian-American (AM) participants were presented with emotional faces from the two racial origins while they performed a gender categorization task. KRs showed significantly greater P3 amplitudes to AM than to KR faces indicating that the early attentional processing underlies differential perception of racial out-group faces. Interestingly, P3 was not up-regulated in the AM subjects when they were presented with KR faces, perhaps due to massive habituation to KR faces during everyday social interaction. These results indicate that racial out-group faces are highly salient stimuli which automatically occupy attentional resources, but easily habituated with repeated exposure to the racial-out group.