• 한국융합학회논문지
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• 제9권5호
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• pp.121-127
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• 2018

본 연구는 55명의 노인 대상자를 무작위로 급속안구운동(saccadic eye movement, SEM)군과 원활추종눈운동(smooth pursuit eye movement, SPEM) 두 군으로 구분하여 4주 동안 안구운동을 실시한 후 사건관련 전위(event-related potentials)중 P300의 전위값과 잠복기 그리고 MMSE-DS를 사용하여 안구운동이 인지능력에 미치는 영향을 알아보고자 하였다. 그 결과 SEM과 SPEM 군의 P300 전위값은 유의하게 상승하였으며, P300의 잠복기는 유의하게 짧아졌다. MMSE-DS 결과 두 군 모두 유의한 상승을 나타냈으며, 군간 비교 시 SEM군은 지남력, SPEM군은 주의력에서 유의한 차이를 나타내었다. 결론적으로 SEM과 SPEM은 노인의 인지능력을 향상 및 유지를 시킬 수 있으며 치매예방과 경도 치매에 대한 치료 도구로 사용될 수 있을 것으로 생각된다.

• 한국문헌정보학회지
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• 제52권4호
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• pp.91-110
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• 2018

본 연구는 비디오 스킴의 자동 생성을 위한 비디오 요약 알고리즘을 제안하고 이를 평가하였다. 제안된 알고리즘은 ERP(Event Related Potentials) 기반의 주제 적합성 모형, MMR(Maximal Marginal Relevance) 기법 및 판별분석기법을 사용하여 구현하였다. 제안한 ERP/MMR 기반 알고리즘을 이용하여 구성한 비디오 스킴의 품질과 유용성을 내재적 및 외재적 평가를 통해서 검증하였다. 내재적 및 외재적 평가에서 ERP/MMR 방법들의 평가 점수들은 각각 경쟁 기준으로 사용한 SBD(Shot Boundary Detection) 방법의 평가 점수 보다 유의미한 차이를 보이며 높게 나왔다. 그러나 이 두 평가에서 ERP/MMR(${\lambda}=0.6$) 방법의 평가 점수와 ERP/MMR(${\lambda}=1.0$) 방법의 평가 점수 간에 통계적으로 유의미한 차이는 없는 것으로 나타났다.

• 말소리와 음성과학
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• 제2권4호
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• pp.3-10
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• 2010

The present study aims to investigate neural activations according to the level of code switching in English proficient bilinguals and to find the relationship between the performance of language switching and proficiency level using ERPs (event-related potentials). First, when comparing high-proficient (HP) with low-proficient (LP) bilingual performance in a native language environment, the activation level of N2 was observed to be higher in the HP group than in the LP group, but only under two conditions: 1) the language switching (between-language) condition known as indexing attention of code switching and 2) the inhibition of current language for L1. Another effect of N400 can be shown in both groups only in the language non-switching (within-language) condition. This effect suggests that both groups completed the semantic acceptability task well in their native language environment without the burden of language switching, irrespective of high or low performance. The latencies of N400 are only about 100ms earlier in the HP group than in the LP group. This difference can be interpreted as facilitation of the given task. These results suggest that HP showed the differential activation in inhibitory system for L1 in switching condition of L1-to-L2 to be contrary to inactivation of inhibitory system for the LP group. Despite the absence of an N400 effect at the given task in both groups, differential latencies between the peaks were attributed to the differences of efficiency in semantic processing.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.283-287
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• 1993

We constructed morphological filter for single sweep records of event-related potential (ERP), especially P300 waveform. By combining 4 basic operations; erosion, dilation, opening and closing, we can derive any desired filters whose property fits the current objectives. The morphological filter for single sweep records of ERP was constructed by taking account of the features of the signal and noise components. The morphological filter has superior properties of separating the signal ancl the noise even existing within a same frequency band. The constructed morphological filter was tested by using simulation data of ERP and then applied to actual ERP data of a normal subject. The results proved that the constructed morphological filter was an appropriate tool for single sweep records of ERP.

• 대한의생명과학회지
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• 제26권1호
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• pp.14-21
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• 2020

Quantitative evaluation of the sense of smell is done by the olfactory event-related potential (OERP) test. OERP consists of N1, P1, N2, P2, and P3, of which N1 and P1 latency are known to be affected by the concentration of odor stimuli associated with the pre-sensory phase and P2 and P3 are the stages at which odors are perceived and are known to change by subjective evaluation of the stimulus. The purpose of this study was to clarify the correlation between the expression of OERP and the subjective evaluation of the object on the fragrance stimulus using various fragrances. Therefore, the study examined the relative waveform power ratio, preference for each scent stimulus, and finally the amplitude and latency change of the components of OERP, N1 and P2. In contrast, it was found that the late P2 response waveform was an effective aroma stimulus recognition waveform in OERP compared to the initial response waveforms.

• 대한의용생체공학회:의공학회지
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• 제27권4호
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• pp.170-179
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• 2006

The purpose of this study was to investigate the spatiotemporal cortical activation pattern and functional connectivity during visual perception of words. 61 channel recordings of electroencephalogram were obtained from 15 subjects while they were judging the meaning of Korean, English, and Chinese words with concrete meanings. We examined event-related potentials (ERP) and applied independent component analysis (ICA) to find and separate simultaneously activated neural sources. Spectral analysis was also performed to investigate the gamma-band activity (GBA, 30-50 Hz) which is known to reflect feature binding. Five significant ERP components were identified and left hemispheric dominance was observed for most sites. Meaningful differences of amplitudes and latencies among languages were observed. It seemed that familiarity with each language and orthographic characteristics affected the characteristics of ERP components. ICA helped confirm several prominent sources corresponding to some ERP components. The results of spectral and time-frequency analyses showed distinct GBAs at prefrontal, frontal, and temporal sites. The GBAs at prefrontal and temporal sites were significantly correlated with the LPC amplitude and response time. The differences in spatiotemporal patterns of GBA among languages were not prominent compared to the inter-individual differences. The gamma-band coherence revealed short-range connectivity within frontal region and long-range connectivity between frontal, posterior, and temporal sites.

• 생물정신의학
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• 제11권1호
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• pp.40-48
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• 2004

Objective:Event-related potentials(ERPs) are electrical changes recorded at the surface of the scalp in response to stimulus presentation, and their latency and amplitude change according to cognitive processes. Through past studies of the auditory ERP in schizophrenia, the P300 has been reported to be statistically smaller and delayed in schizophrenia than comparison groups. However, studies of the visual ERP have not been systematically examined. The present study was designed to investigate the visual P300 in patients with schizophrenia and normal controls and to compare the pattern of P300 between them. Methods:The subjects were composed of patients(N=22) with schizophrenia by DSM-IV and normal controls(N=22). The visual ERPs were measured by the visual continuous performance test. P300 amplitude and latency measured on 5 scalp electrodes(Fz, Cz, Pz, $T_7$, $T_8$) were compared between patients and controls. Results:The P300 latencies measured on Fz, Cz, Pz, and $T_7$ electrodes were significantly longer in patients than controls(p<0.05). The P300 amplitudes in patients were smaller than controls. However, the difference between them was not statistically significant. Conclusion:Analysis of the visual ERPs showed that the P300 latency is significantly delayed and the P300 amplitude is slightly smaller in patients than controls. These results are similar to established studies of the auditory P300 in schizophrenia.

• 정보관리학회지
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• 제36권3호
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• pp.131-148
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• 2019

본 연구는 시청자가 사운드 자료의 주제를 파악하는 과정과 사운드의 특성을 이해하기 위한 인지적 정보처리 모형을 구성하였다. 이후 사건관련유발전위(event related potentials, ERP)의 두뇌의 전후측에 걸쳐서 발현하는 N400, P600 구성요소들을 인지적 정보처리 모형의 언어적 표상에 접목시켜 사운드 요약을 생성하는 방안을 제안하기 위해서 연구 가설들을 수립하였다. 뇌파 실험을 통해서 연구 가설들을 검증한 결과, P600이 사운드 요약의 핵심 구성 요소로 나타났다. 본 연구 결과는 분류 알고리즘 설계에 적용되어 내용 기반 메타데이터 즉, 일반적인 또는 개인화된 미디어 요약(사운드 요약, 비디오 스킴)을 생성하는 데에 활용될 수 있을 것이다.

• 사상체질의학회지
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• 제22권1호
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• pp.41-48
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• 2010

1. Objective There has been a few trials to diagnose Sasang Constitution by using EEG, but has not been studied intensively. For the purpose of practical diagnosis, the characteristics of EEG for each constitution should be studied first. Recently it has been shown that Sasang Constitution might be related to harm avoidance and novelty seeking in temperament and character profiles. Based on this finding, we propose a visual stimulation method to evoke a EEG response which may discriminate difference between constitutional groups. Through the experiment with this method, we tried to reveal the characteristics of EEG of each constitutional groups by the method of event-related potentials. 2. Methods: We used facial visual stimulation to verify the characteristics of EEG for each constitutional groups. To reveal characteristic in sensitivity and latency of response, we added several levels of noise to facial images. 6 male subjects(2 Taeeumin, 2 Soyangin, 2 Soeumin) participated in this study. All subjects are healthy 20's. To remove artifacts and slow modulation, we removed EOG contaminated data and renormalization is applied. To extract stimulation related components, normalized event-related potential method was used. 3. Results: From Oz channels, it is verified that facial image processing components are extracted. For lower level noise, components related to the visual stimulation were clearly shown in Oz, Pz, and Cz channels. Pz and Cz channels show differences among 3 constitutional groups in maximum around 200 msec. Especially moderate level of noise looks appropriate for diagnosis. 4. Conclusion: We verified that the visual stimulation with facial emotion might be a good candidate to evoke the differences between constitutional groups in EEG response. The differences shown in the experiment may imply that the process of emotion has distinct tendencies in latencies and sensitivity for each consitutional group. And this distinction might be related to the temperament profile of consitutional groups.

• 한국콘텐츠학회논문지
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• 제16권5호
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• pp.242-250
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• 2016

본 연구는 스트룹(Stroop)과제를 이용하여 정서가(affective valence)로 구성된 역하의 정서유발 점화자극이 인지과제 수행에 영향을 미치는지와 일반인에서도 정서장애 환자와 같은 지표가 나타나는지를 반응시간과 ERP(사건관련전위) 패턴으로 확인해 보고자 하였다. 측정된 데이터는 정서가(긍정 및 부정)와 일치여부로 수행되는 인지과제의 조합으로 제시되어 수집되었고, 전위변화의 특성인 진폭과 정점 잠복기를 기준으로 그 효과가 검증되었다. 먼저 반응시간 행동분석 결과, 중립 정서자극을 제외한 역하의 정서자극에 의해 목표과제의 반응을 촉진하는 결과를 확인할 수 있었다. 아울러 부가적으로 수집된 사건관련전위를 분석한 결과, 불일치 요인이 결합된 부정적 정서정보가 긍정적 정서정보에 비해 더 높은 음전위 및 지연된 잠복기를 보임으로써 표정과 관련된 정서유발-특정적인 N2효과를 확인하였다. 그리고 동일한 조건에서 긍정조건에 비해 유의한 차이의 양전위와 함께 더 짧은 잠복기를 보이는, 인지적 판단과정의 차이를 시사하는 P300의 효과도 관찰하였다. 이는 역하의 부정적 정서정보가 인지처리과정에서 자동적으로 억제되는 경향과 함께 해당 정서의 탐지를 가속시키는 한편, 주의자원의 적절한 재분배를 가능케 하여 목표자극의 반응을 촉진시킨 것으로 해석할 수 있으며, 기능적이고 인지적인 반응의 차이에서 역하효과를 비롯하여 과제 수행 정도에 영향을 끼치는 정서관련 재인과정의 중요성을 시사한다 할 수 있다.