Cognitive neuroscience of attention and sensory working memory.

我的研究项目试图了解注意力、工作记忆和认知控制的基本机制的功能和神经元特征。拟议的实验建立在过去成功使用脑电、脑磁图(具有高时间分辨率的方法)的基础上，并指导旨在理解电磁振荡大脑活动所反映的认知功能的新研究。 将开发新的相位-幅度耦合动态变化和区域间试验间相位同步的测量方法，并用于分析脑振荡活动。然而，仅就大脑各部位之间相互作用的方向或性质而言，相位同步本身并不能提供信息。最近基于格兰杰因果关系的工作有望消除已识别网络节点之间信息流的方向。我建议使用这种方法来理解网络交流在空间选择和信息编码到视觉工作记忆中的动态。 具体实验将考察空间选择与N2pc事件相关的偏侧化，以及N2pb双侧后方注意反应。视觉工作/短期记忆将通过SPCN(持续的对侧后负波)来索引。一些实验将检验被假定为反映干扰抑制的干扰正向(PD)。 目标-分心物体的交互作用也将在注意瞬脱(AB)范式中进行研究，重点放在格兰杰因果关系中的相位同步和不对称性的测量上，但使用注意驻留方法，该方法不会诱导强烈的稳态诱发反应，从而难以区分“自然”振荡和刺激驱动的振荡(这是以前工作中的一个问题)。AB研究将通过包括有或没有任务切换的条件来扩展，提供关于底层网络节点的认知控制的信息。 基于标准信号平均方法(N2pc、N2pb、SPCn、P3)的分析保证了短期的成功，而对振荡活动的复杂分析有望将该领域推进到对调节大脑活动的理解的新水平。 这项研究将由学习认知神经科学的本科生和研究生以及博士后研究员进行，因此将在一个令人兴奋和不断扩大的NSE研究领域为HQP的培训做出贡献。

My resarch program seeks to understand functional and neuronal characteristics of basic mechanisms of attention, working memory, and cognitive control. Proposed experiments build on past successes in the use of EEG, MEG (methods with high temporal resolution), and guide new studies designed to understand cognitive funtions reflected by electromagnetic oscillatory brain activity. New measures of dynamic changes in phase-amplitude coupling and inter-regional inter-trial phase synchrony, will be developed and used in the analysis of oscillatory brain activity. However, phase synchrony alone is not informative in terms of the direction or nature of interaction among brain sites. Recent work based on on Granger causality holds promise to disambiguate the direction of information flow among nodes of identified networks. I propose to use this approach to understand the dynamics of network communcation in spatial selection and the encoding of information into visual working memory. Specific experiments will examine selection in space with the N2pc event-related lateralization, and the N2pb bilateral posterior attention response. Visual working/short-term memory will be indexed by the SPCN (sustained posterior contralateral negativity). Some experiments will examine the distractor positivity (Pd) posited to reflect distractor suppression. Target-distractor interactions will also be examined in the attentional blink (AB) paradigm, with a focus on measures of phase synchrony and asymmetries in Granger causality, but with the attentional dwell approach, which does not induce strong steady-state evoked responses that make it difficult to distinguish between 'natural' oscillations from stimulus-driven oscillations (a problem in previous work). AB studies will be extended by including conditions with or without task switching, providing information concerning cognitive control of underlying network nodes. Analyses based on standard signal-averaging methods (N2pc, N2pb, SPCN, P3), guarantee short-term successes, while sophisticated analyses of oscillatory activity promise to advance the field to a new level of understanding of mediating brain activity. The research will be carried by undergraduate and graduate students studing in cognitive neuroscience, postdoctoral fellows, and thus will contribute the training of HQP in an exciting and expanding area of NSE research.