Defining the neural correlates of ensemble representation

描述(由申请人提供)：定义人类整体表征的神经关联对复杂场景的汇总统计很敏感。视觉系统容易地提取跨越包括方向、运动方向、大小、位置和表情在内的多个视域的汇总统计表示，并且可以高效且隐含地这样做。摘要统计提取，或集合编码，在空间和时间上操作，并显示对对象集合的平均值、范围、甚至方差的敏感性。尽管集合表征似乎无处不在，具有基本的性质，但集合提取的确切水平仍然未知，也没有对这一过程的神经关联进行检查。这些问题将使用低水平的行为心理物理学和功能神经成像技术来探索。拟议的实验将描述理解汇总统计在视觉中所起作用的关键要素，包括：a)视觉系统是否以适应单一刺激(例如，单一定向Gabor面片、单一脸部)的相同方式来适应整体刺激(例如，定向Gabor面片集合、脸部集合)？B)大脑的哪些部分在计算/提取汇总统计信息方面发挥作用？拟议研究的更广泛目标是发展功能磁共振成像技术方面的专门知识，范围从设计(例如，区块、快速事件相关)到分析(例如，去卷积、模式分类)。

DESCRIPTION (provided by applicant): Defining the neural correlates of ensemble representation in humans are sensitive to the summary statistics of complex scenes. The visual system readily extracts summary statistical representations across a host of visual domains, including orientation, direction of motion, size, position, and expression, and can do so efficiently and implicitly. Summary statistical extraction, or ensemble coding, operates over both space and time, and shows sensitivity to the average, the range, and even the variance of sets of objects. Despite the seeming ubiquitous and fundamental nature of ensemble representations, the precise level at which ensembles are extracted remains unknown, and there has been no examination of the neural correlates of this process. These issues will be explored using low-level behavioral psychophysics and functional neuroimaging techniques. The proposed experiments will delineate elements key to understanding the role summary statistics play in vision, including: a) does the visual system adapt to ensemble stimuli (e.g., sets of oriented gabor patches, sets of faces) in the same way that it adapts to singletons (e.g., a single oriented gabor patch, a single face)? b) What parts of the brain play a role in calculating/extracting summary statistical information? The broader objective of the proposed studies is to develop expertise in functional magnetic resonance imaging techniques, ranging from design (e.g., block, fast event-related) to analysis (e.g., deconvolution, pattern classification).