Gaze-track representation in high-level visual cortex

当我们看一张脸时，我们会进行独特的眼球运动，导致视线路径很容易与其他物体引起的视线路径区分开来。众所周知，额叶和顶叶区域支持这种眼球运动的规划和执行。然而，我们最近发现，面部和房屋特定的凝视轨迹可以在梭状面部区域（FFA）和海马旁位置区域（PPA）中解码-即使在没有面部或房屋的情况下也是如此。我们的结论是，动作（凝视）模式是在高级视觉皮层，表现出一个潜在的神经基础的感知和行动的密切相互作用。虽然我们认为我们已经为这种违反直觉的复杂凝视模式在高级感知区域的映射提供了坚实的证据，但关于它们的性质和功能的许多问题仍然存在。在本提案的第一个实验中，我们想研究这一新发现的性质，特别是在什么时候关键信息被表示在注视轨迹中，以及它是否被编码在序列中，或者更确切地说是固定的位置。在第二个实验中，我们想知道当识别面部时引起的注视轨迹是否在不同的感知大脑区域中表示。最后，我们计划调查，如果在面部观察引起的微眼跳表示在FFA的眼跳类似的方式。

When we look at a face, we carry out distinctive eye movements leading to gaze paths that can easily be discriminated from the gaze paths elicited by other objects. It is well-known that frontal and parietal areas support the planning and execution of such eye movements. However, we recently showed that face and house-specific gaze tracks can be decoded in the fusiform face area (FFA) and the parahippocampal place area (PPA) - even in the absence of a face or house to look at. We concluded that action (gaze) patterns are represented in high-level visual cortex, demonstrating a potential neural basis for close interactions of perception and action. While we think we have presented solid evidence for this counterintuitive mapping of complex gaze patterns in high-level perceptual areas, many questions as to their nature and function remain. In the first experiment of the present proposal, we want to investigate the nature of this novel finding, specifically at what time the critical information is represented in a gaze track and if it is coded in the sequence or rather the location of fixations. In a second experiment, we want to learn if the gaze tracks elicited when identifying a face respectively identifying a facial emotion expression are represented in different perceptual brain areas. Finally, we plan to investigate if microsaccades elicited during face viewing are represented in a similar way as saccades in the FFA.