範德堡大學丁肇華博士訪問bet356手机版唯一官网并做學術報告

報告題目：Visualizing ‘Dark Matter’ in the Human Brain Using Functional Magnetic Resonance Imaging: Methods and Applications

報告時間：2019年4月26日上午10:30(星期五)

報告地點：bet356手机版唯一官网四牌樓校區中山院112室

報告摘要：Functional magnetic resonance imaging based on blood oxygenation level dependent (BOLD) contrast has proven to be effective in detecting neural activity in brain cortices. Due to reduced vascular density in white matter, BOLD signals therein tend to be weak, which renders white matter to be functionally ‘dark matter’in the human brain. We have demonstrated that BOLD signals acquired at resting state exhibit structure-specific temporal correlations along white matter tracts, and thus proposed the concept of spatio-temporal correlation tensors to characterize the directional preferences of temporal correlations in white matter BOLD signals. We found that the spatio-temporal correlation tensors are able to visualize both long range white matter tracts and short range sub-cortical fibers imaged at rest, that evoked functional activities enhance visualization of relevant neural circuits in white matter, and that pathological conditions alter correlational profiles of BOLD signals along related white matter tracts.

  This lecture will consist of five major parts. First, methodological details that include protocols for image acquisitions and processing and approaches for constructing spatio-temporal correlation tensors from BOLD time series will be described. Second, illustrative examples demonstrating the anisotropy of spatio-temporal correlations in resting state BOLD signals and directional consistency with white matter tracts depicted using structural imaging will be presented. Third, effects of functional loading, including visual stimulations and performance of reading tasks, in selectively visualizing relevant neural circuitry will be demonstrated. Fourth, major reported and unreported evidence gleaned from a plethora of research groups that attests to the measurability of BOLD signals in white matter will be summarized. And finally, applications of the proposed spatio-temporal correlation tensors to clinical studies of the impact of neurological disorders on correlational profiles of BOLD signals in relevant neural circuits will be exemplified with pontine stroke and Alzheimers disease. The lecture will conclude with an outline of potential technical issues and future directions for continued technical development.

報告人簡介：丁肇華博士是具有20多年生物醫學工程和成像專業經驗的資深專家。擁有生物醫學工程本科、碩士和博士學位以及計算機碩士學位。先後在美國俄亥俄州立大學、耶魯大學和範德堡大學學習和工作。目前擔任範德堡大學成像科學研究所，電氣工程和計算機系，以及生物醫學工程系研究副教授，博士和博士後導師。是國際電氣工程師學會資深會員，任十餘家國際期刊、會議和美國國家衛生部基金評審委員。在國際期刊和會議發表論文200餘篇，包括PNAS，Nature Communications, IEEE TPAMI, TMI和TIP等知名期刊，論文被他引7000餘次。主要研究醫學磁共振及其在人腦功能結構關系中的應用，在幾個重要方向上屬國際領先。2013年首創了功能張量成像概念，在國際學術界引起了廣泛關注。2014年榮膺國際電氣工程師學會頒發的最佳論文獎。