Reserve Correlation Mapping in Face Patches

描述(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。脸是所有可能的视觉形状的复杂但高度受限的子集。已使用功能磁共振成像(FMRI)确定了颞叶中的面部选择性区域，显示出与其他物体的图像相反，面部的视觉刺激导致血流量增加。因此，MRI可用于将单单元记录定向到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元记录的能力提供了一个前所未有的机会，可以从完全选择性地进行面部的颞叶皮质区域进行重复记录。其中一组双侧面部斑块位于上颞沟的下岸，很可能对应于人类梭形面部区域(FFA)。本实验室已经在两个被试中成功地将单单位记录定向到了这个面孔贴片上，并且在这个区域到目前为止记录的几乎所有(98%)的单单位对面孔都表现出了很强的反应选择性。单单位电生理学和功能磁共振成像将并行和联合使用，以探索颞叶面部选择性区域的功能专门化和面部加工的分层组织，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。单单位反向相关映射和功能磁共振成像将被用来将选择性映射到在视角、位置、比例、照明和表情上不同的大组人脸，以探索沿着人脸处理层次的不变编码的发展。逆相关映射将用于在参数化的人工脸空间中映射多个面部特征的选择性，以确定这些区域中的特征如何组合，以从更简单的特征或特征星座生成面部选择性响应属性。人脸识别是高级视觉处理中最重要的社会和发展方面之一。了解大脑是如何执行人脸识别这样一个复杂而具体的过程的，将有助于深入了解人类的认知，以及面孔识别受损的神经和精神疾病，如面孔失认症、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.