Reverse Correlation Mapping in V2 and V4

描述（由申请人提供）：该项目的目标是探索人脸检测和识别的功能解剖和机制。面是所有可能的视觉形状的复杂但高度受限的子集。颞叶中的面部选择性区域已经被功能性磁共振成像（fMRI）识别为显示出对面部视觉刺激的反应增加的血流，而不是其他物体的图像。因此，MRI可用于将单单位记录靶向这些面部选择性区域。专门针对fMRI识别的面部斑块进行单单位记录的能力提供了一个前所未有的机会，可以从完全选择面部的颞叶皮层区域重复记录。一组双侧面部斑块位于上级颞沟的下段，可能对应于人类梭状面区（FFA）。该实验室已经成功地针对两个受试者的面部斑块进行了单单元记录，并且在该区域中，迄今为止记录的几乎所有（98%）的单单元都表现出对面部的强烈响应选择性。单单位电生理学和功能磁共振成像将被并行和结合使用，以探索颞叶面部选择区域的功能专业化和面部处理的层次组织，特别是不同的区域是否专门用于处理面部的特定方面，如情绪表达，视角，或凝视方向。单单元反向相关映射和功能磁共振成像将被用来映射选择性的大集合的不同的视角，位置，规模，照明和表情，探索不变的编码沿着的脸处理层次的发展。逆相关映射将用于映射参数化人工面部空间中的多个面部特征的选择性，以确定如何在这些区域中组合特征，从而从更简单的特征或特征星座中生成面部选择性响应特性。人脸识别是社会性和发展性的高级视觉加工中最重要的方面之一。了解大脑如何执行人脸识别这样一个复杂而具体的过程，将有助于深入了解人类认知以及人脸识别受损的神经和精神疾病，如面容失认症，精神分裂症和自闭症。

DESCRIPTION (provided by applicant): The project goal is to explore the functional anatomy and mechanisms of face detection and recognition. Faces are a complex yet highly constrained subset of all possible visual shapes. Face-selective regions in the temporal lobe have been identified using functional magnetic resonance imaging (fMRI) as showing increased blood flow in response to visual stimulation with faces as opposed to images of other objects. MRI can therefore be used to target single-unit recording to these face-selective regions. The ability to specifically target fMRI-identified face patches for single-unit recording provides an unprecedented opportunity to record repeatedly from areas of temporal cortex entirely selective for faces. One bilateral set of face patches is in the lower bank of the superior temporal sulcus and likely corresponds to the human fusiform face area (FFA). This laboratory has successfully targeted single-unit recording to this face patch in two subjects, and in this region almost all (98%) of the single units recorded so far have shown strong response selectivity for faces. Single-unit electrophysiology and fMRI will be used in parallel and in conjunction to explore the functional specialization in the face-selective regions of the temporal lobe and the hierarchical organization of face processing, in particular whether distinct regions are dedicated to processing specific aspects of faces, such as emotional expression, view angle, or gaze direction. Single-unit reverse correlation mapping and fMRI will be used to map selectivity to large sets of faces varying in view angle, position, scale, illumination, and expression to explore the development of invariant coding along the face-processing hierarchy. Reverse-correlation mapping will be used to map selectivity for multiple facial features in a parameterized artificial-face space to determine how features are combined in these areas to generate face-selective response properties from simpler features or feature constellations. Face recognition is one of the most important aspects both socially and developmentally of higher-level visual processing. Understanding how the brain carries out such a complex yet specific process as face recognition will yield insights into human cognition as well as into neurological and psychiatric conditions in which face recognition is impaired, such as prosopagnosia, schizophrenia, and autism.