EFFECTIVE CONNECTIVITY IN BRAIN IMAGING OF VISION

描述(由申请人提供)：本提案由试点研究小额拨款支持计划赞助提交，旨在寻求资金用于开发、改进和验证分析技术，以推断前馈和反馈对多个视觉区域的fMRI激活的相对贡献。具体地说，我们将使用非线性方程来模拟当人类观察者报告与观看双眼竞争相关的视觉感知的波动时测量的激活(使用功能磁共振成像记录的血氧水平依赖信号)(即，由单独的眼睛观看的两个不同图像之间的视觉感知的变化)。这些分析技术在文献中被描述过(Buchel&Friston，1995)，但很少被用于视觉研究，尽管它们有可能显著扩大从脑成像研究得出的结论的范围。鉴于功能磁共振成像在视力及其疾病研究中的应用急剧增加，迫切需要开发、改进和验证技术，以扩大使用功能磁共振成像可以解决的问题的范围。目前的提议具有这种潜力。

DESCRIPTION (provided by applicant): This proposal, submitted under the auspices of the program supporting Small Grants for Pilot Research, seeks funds to develop, refine and validate analytic techniques for inferring the relative contributions of feedforward and feedback contributions to fMRI activations in multiple visual areas. Specifically, we will use nonlinear equations to model activations (blood oxygen-level dependent signals registered using functional magnetic resonance imaging) measured while human observers report fluctuations in visual perception associated with viewing binocular rivalry (i.e., the alternations in visual awareness between two dissimilar images viewed by the separate eyes). These analytic techniques have been described in the literature (Buchel & Friston, 1995) but have been rarely employed in studies of vision, despite their potential for significantly extending the range of conclusions drawn from brain imaging studies. Given the dramatic increase in the use of fMRI for the study of vision and its disorders, it is imperative to develop, refine and validate techniques that extend the range of problems that can be addressed using fMRI. The present proposal has this potential.