VISUAL PROCESSING IN CEREBRAL CORTEX

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 注意力是感官和认知表现的关键因素。 在控制和引导注意力方面的问题可能会导致表现和行为方面的严重缺陷。 关于注意力背后的神经机制的更完整的信息对于理解注意力如何促进感知和指导行为非常重要。 我们的实验将扩展我们的注意力的神经元基础的理解，通过测试的假设，即注意力调制取决于相同的神经回路，介导的感觉反应正常化。 反应正常化是一种成熟的机制，它基于具有相似反应特性的一大群神经元的整体活动来调节感觉信号。 我们认为，视觉大脑皮层中的注意力调制通过这种正常化机制起作用，这样，注意力调制就不能发生在正常化弱或消除的条件下。这些实验将为注意力依赖于正常化机制这一假设提供一个关键的检验。 这样一来，他们就有可能极大地扩展我们对注意力背后的神经机制的理解。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Attention is a critical factor in sensory and cognitive performance. Problems in controlling and directing attention can lead to serious deficits in performance and behavior. More complete information about the neural mechanisms underlying attention will be important for understanding how it facilitates perception and guides behaviors. Our experiments will extend our understanding of the neuronal basis of attention by testing the hypothesis that attentional modulation depends on the same neuronal circuits that mediate sensory response normalization. Response normalization is a well-established mechanism that adjusts sensory signals based on the overall activity in a large group of neurons with similar response properties. We propose that attentional modulations in visual cerebral cortex act through this normalization mechanism, such that attentional modulation cannot occur in conditions when normalization is weak or eliminated. These experiments will provide a critical test of the hypothesis that attention depends on normalization mechanisms. In doing so they have the potential of greatly extending our understanding of the neural mechanisms that underlie attention.