Dissecting the neural circuits for face perception in macaque inferotemporal cort

描述（由申请人提供）：本提案的目标是了解猕猴大脑调节面部感知的神经回路。面孔是灵长类动物大脑处理的最有意义的视觉形式之一，传达有关身份，表情，性别，年龄和注意力方向的信息。功能性磁共振成像（fMRI）揭示了猕猴颞叶中面部处理的专门化：皮质的六个离散区域对面部图像的反应比其他物体的图像强烈得多。这些区域对面孔的专门化程度是惊人的：当以单一单位记录为目标时，迄今为止广泛测试的所有四个区域几乎完全由面孔选择细胞组成。这些区域被称为“面部斑块”，位于两个半球和个体之间的相似位置。结合功能磁共振成像与微刺激的实验表明，面部斑块是强烈和具体的相互联系，但电生理实验表明，不同的补丁是功能不同的。面部补丁系统提供了一个独特的机会，解剖神经机制的形式感知，因为该系统是专门处理一类复杂的形式，因为它的计算组件是空间隔离。我们认为，理解面部斑块系统的核心实验挑战是理解每个斑块的功能特化以及这种特化是如何产生的。为了应对这一挑战，我们计划从四个方向询问系统：1）表示：每个人脸补丁中细胞的选择性和不变性是什么？2)行为作用：使特定面部斑块失活对各种面部相关行为有什么影响？3)连通性：面部贴片的接线图是什么？，和4）转换：在每个面部补丁内输入和输出细胞之间的关键功能差异是什么？解决这些问题将阐明面部补丁系统内的信息流的原则，并阐明颞下皮层的一般组织原则。

Description (provided by applicant): The goal of this proposal is to understand the neural circuits of the macaque brain mediating face perception. Faces are among the most meaningful visual forms processed by the primate brain, conveying information about identity, expression, gender, age, and direction of attention. Functional magnetic resonance imaging (fMRI) reveals a specialization for face processing in the macaque temporal lobe: six discrete regions of cortex respond much more strongly to images of faces than to images of other objects. The degree of specialization of these regions for faces is breathtaking: when targeted for single-unit recording, all four regions tested extensively so far turned out to consist almost entirely of face-selective cells. These regions, termed "face patches", are located at similar positions in the two hemispheres and across individuals. Experiments combining fMRI with microstimulation demonstrate that the face patches are strongly and specifically interconnected, yet electrophysiological experiments show that different patches are functionally distinct. The face patch system offers a unique opportunity to dissect the neural mechanisms underlying form perception, because the system is specialized to process one class of complex forms, and because its computational components are spatially segregated. We believe the central experimental challenge to understanding the face patch system is to understand the functional specialization of each patch and how this specialization comes about. To address this challenge, we plan to interrogate the system from four directions: 1) Representations: What are the selectivity and invariance properties of cells in each face patch?, 2) Behavioral Role: What is the effect of inactivating specific face patches on various face-related behaviors?, 3) Connectivity: What is the wiring diagram of the face patches?, and 4) Transformations: What are the key functional differences between input and output cells within each face patch? Addressing these questions will elucidate the principles of information flow within the face patch system and shed light on the general organizing principles of inferotemporal cortex.