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뇌과학연구센터에서 다음과 같이 세미나를 개최합니다.
관심있는 분들의 많은 관심 부탁드립니다.

- 일시 : 2003년 7월 30일 오후 4:00-5:30
- 장소 : LG Semicon Hall 1층 멀티미디어실

- 제목 : Waves of activity in V1 correlate with waves of dominance during binocular rivalry
- 연사 : Sang-Hun Lee, NYU

- 초록
When the two eyes view large dissimilar patterns, alternating waves of visibility are experienced, as one pattern sweeps the other out of awareness. Do neural events in V1 correlate with the spatiotemporal dynamics of those waves? Methods: Subjects saw dichoptic displays while fMRI signals were measured in a 3T scanner. Each 9-sec trial began by showing a low-contrast radial grating, restricted to an annulus (3.6-4.4°) around fixation, to one eye. This was followed immediately by showing a high-contrast spiral grating, restricted to the same annulus, to the other eye. This promoted complete suppression of the low-contrast pattern. Shortly thereafter, a brief contrast increment appeared in a narrow region at the top of the suppressed pattern. This triggered dominance of that region of the annulus, with this dominance then spreading such that the low-contrast pattern progressively erased the high-contrast for 1–2.5 s. When the wave reached the bottom of the annulus, observers pressed a key, which caused the annulus to disappear, then classified waves based on their direction and quality: ‘left hemifield’, ‘right hemifield’ or ‘no’ wave. Results: During binocular rivalry, latencies and amplitudes of fMRI signals in V1 varied orderly across the retinotopic map: signal fluctuations were more delayed and larger in more dorsal portions of this map. The differences in latency and amplitude were correlated with the latency, direction and quality of perceptual waves. Similar patterns of signal fluctuations were found when composite monocular patterns were shown to mimic perceptual waves that observers saw during rivalry. The directionality of neural waves during rivalry was maintained when observers diverted attention away from the annulus so that they could not track dominance waves attentively. Conclusion: The fine-scale analysis of fMRI signals reveals a tight link between dynamics of dominance waves during rivalry and neural events in V1.



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Fifth China-India-Japan-Korea Joint Workshop on Neurobiology and Neuroinformatic

일시 : November 21-22, 2003
장소 : Jung MoonSoul Building, KAIST, Daejeon, Korea
자세한 내용 : NBNI 2003 홈페이지



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뇌신경정보학연구사업 2차년도 전문가 평가 공고

- 일시 : 2003년 4월 29일(화) 10:00-20:30
- 장소 : 한국과학기술기획평가원 5층 5회의실

- 발표자료 제출 : 2003년 4월 28일(월) 오후 1시까지(e-mail로 : bsrc@neuron.kaist.ac.kr)
- 중과제는 15분, 세부과제는 10분, 단위과제는 15분(과제에 대한 평가위원의 질의 응답을 포함하므로 실제 발표시간은 중과제 10분, 세부 5분, 단위 10분 정도입니다.)


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