Wavelet cross correlation을 이용한 의식적인 의도와 무의식적인 의도에 따른 뇌활성 신호의 특징 추출 = Wavelet Cross-correlation Estimation of the Optical Neuronal Signals on Conscious, Subconscious, and no Intentions

국문 초록 (Abstract)

본 논문에서는 웨이블릿 상호 상관 기법을 이용하여 근적외선 분광기로부터 추출할 수 있는 slow signal에 내재되어 있는 잡음 신호의 영향을 배제하고 의식적인 의도와 무의식적인 의도에 따른 뇌활성 신호의 특징을 추출하였다. 본 논문의 실험을 위하여 기존의 choice reaction time 테스크와 n-back working memory 테스크의 프로토콜을 응용하여 의도형 추출 테스크를 고안하였으며 실험 설정 단계서 의도형 선택 설정이 가능하도록 구성하였다. 산화헤모글로빈과 탈산화헤모글로빈의 농도로부터 의도형 기반 뇌활성 신호의 특징을 추출하기 위해 Morlet 웨이블릿 변환을 수행한 후 그 결과를 상호 상관계수를 이용하여 분석하였다. 결과적으로 의도형 추출 테스크에 있어서 자극신호가 주어진 시점을 전후로 전전두엽 영역으로부터 기록되는 뇌혈류역학 신호의 특이적인 변화를 관찰할 수 있었으며 의식적인 의도와 무의식적인 의도에 따라 뚜렷이 구별되는 웨이블릿 상관 계수의 분포를 구할 수 있었다.

다국어 초록 (Multilingual Abstract)

In this study, neuronal signals related with conscious or subconscious intention were analyzed by wavelet cross-correlation estimation. The neuronal signals were recorded from the prefrontal cortexes using functional near infrared spectroscopy while subjects were carrying out intention type extraction tasks. The intention type extraction task was invented based on the conventional choice reaction time and n-back working memory experiment protocols and was carried by presetting up to one of three intention types, such as conscious intention, subconscious intention and no intention. The results showed that the neuronal signals by conscious intention type are associated with the range of the wavelet scales from 100 to 160 while those by subconscious intention and no intention types are associated with the range of the wavelet scales less than 60. The results also showed that the correlations between conscious and subconscious intention types have relatively larger values than those between conscious or subconscious intention type and no intention type.

목차 (Table of Contents)

• 요약
• Abstract
• 1. 서론
• 2. 실험 및 방법
• 3. 결과
• 4. 결론
• 참고문헌

참고문헌 (Reference)

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