• 대한의용생체공학회:의공학회지
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• 제29권1호
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• pp.73-81
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• 2008

The purpose of this study is to observe the brain activity patterns during visual oddball tasks with two difficulty levels by the analysis of high-density event-related potential (ERP). Along with conventional statistical analysis of averaged ERP waveforms, we applied independent component analysis (ICA) for the individual, single-trial analysis and verified its effectiveness. We could identify multiple ERP components such as early visual components (P1, N1), and two components which seem to be important task-related components and showed difficulty-dependent variability (P2, P300). The P2 was found around central region at $180{\sim}220ms$, and the P300 was found globally at $300{\sim}500ms$ poststimulus. As the task became difficult, the P2 amplitude increased, and the P300 amplitude decreased. After single-trial ERPs were decomposed into multiple independent components (ICs), several ICs resulting from P2 and P300 sources were identified. These ICs were projected onto scalp electrodes and the projected ICs were statistically compared according to two task difficulties. For most subjects, the results obtained from single-trial/individual analysis using ICA gave the tendencies of amplitude change that are similar to the averaged ERP analysis for most subjects. The temporal pattern and number of ICs corresponding to ${\mu}$ rhythm was not dependent on the task difficulty. It seems that the motor response was not affected by the task difficulty.

• 한국멀티미디어학회논문지
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• 제20권12호
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• pp.1856-1864
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• 2017

The ultimate goal of multimedia in bio-signal research is to approach multimedia contents through bio-signal. Hence it is important to interpret user's emotions by analyzing his or her bio-signals. In this paper, we construct ERP task of oddball component to analyze EEG signal between normal stimuli and fear stimuli and measure EEG during ERP task. The results from extracted ERP component show that there is a difference in N200 in visual stimuli, P300 in auditory stimuli, and N100 and P300. Moreover, there are larger changes in audiovisual stimuli, indicating that users recognize greater fear of crime when visual and auditory stimuli are simultaneously presented.

• 감성과학
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• 제13권1호
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• pp.179-186
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• 2010

본 연구는 Duncan-Johnson과 Donchin(1979)과 Soskins, Rosenfeld와 Niendam(2001)의 연구를 부분적으로 확장한 것으로, EEG를 측정할 때 사용하는 고역통과필터의 값이 P300의 파형에 미치는 영향을 관찰하였다. 시각자극을 이용한 세자극 오드볼 과제를 수행하는 동안 뇌파를 측정하였으며, Fz와 Pz에서 측정한 뇌파를 0.01Hz, 0.3Hz와 1.0Hz의 고역통과필터를 사용하여 여과시켰다. 0.3Hz의 고역통과필터를 사용한 경우에는 P300 진폭이 크게 감소하지 않았지만, 1.0Hz의 고역통과필터는 P300의 진폭을 크게 감소시켰다. 0.01Hz의 고역통과 필터를 사용한 경우에는 P300 이후 부적 정점이 나타나지 않았으며, 0.3Hz와 1.0Hz의 고역통과필터를 사용한 경우에는 P300 이후 부적 정점이 관찰되었다. 비목표자극과 표준자극에 대한 P300의 진폭을 변별할 때에는 0.3Hz 고역통과필터와 정점-정점 P300 측정치를 사용하는 것이 0.01Hz나 0.3Hz, 1.0Hz 고역통과필터와 기저선-정점 측정치를 사용하는 것보다 더 효율적인 경향이 있었으며, 1.0Hz의 고역통과필터를 사용한 경우에는 정점-정점 P300 측정치가 기저선-정점 P300 측정치보다 더 유용한 경향이 있었다.