Thielen Jordy, Bosch Sander E, van Leeuwen Tessa M, van Gerven Marcel A J, van Lier Rob
Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands.
Iperception. 2019 Apr 8;10(2):2041669519840047. doi: 10.1177/2041669519840047. eCollection 2019 Mar-Apr.
Amodal completion is the phenomenon of perceiving completed objects even though physically they are partially occluded. In this review, we provide an extensive overview of the results obtained from a variety of neuroimaging studies on the neural correlates of amodal completion. We discuss whether low-level and high-level cortical areas are implicated in amodal completion; provide an overview of how amodal completion unfolds over time while dissociating feedforward, recurrent, and feedback processes; and discuss how amodal completion is represented at the neuronal level. The involvement of low-level visual areas such as V1 and V2 is not yet clear, while several high-level structures such as the lateral occipital complex and fusiform face area seem invariant to occlusion of objects and faces, respectively, and several motor areas seem to code for object permanence. The variety of results on the timing of amodal completion hints to a mixture of feedforward, recurrent, and feedback processes. We discuss whether the invisible parts of the occluded object are represented as if they were visible, contrary to a high-level representation. While plenty of questions on amodal completion remain, this review presents an overview of the neuroimaging findings reported to date, summarizes several insights from computational models, and connects research of other perceptual completion processes such as modal completion. In all, it is suggested that amodal completion is the solution to deal with various types of incomplete retinal information, and highly depends on stimulus complexity and saliency, and therefore also give rise to a variety of observed neural patterns.
非模态完成是指即使物体在物理上部分被遮挡，仍能感知到完整物体的现象。在这篇综述中，我们广泛概述了从各种关于非模态完成神经关联的神经影像学研究中获得的结果。我们讨论了低层次和高层次皮层区域是否与非模态完成有关；概述了非模态完成如何随着时间展开，同时区分前馈、循环和反馈过程；并讨论了非模态完成在神经元水平上是如何表现的。诸如V1和V2等低层次视觉区域的参与情况尚不清楚，而诸如枕外侧复合体和梭状面孔区等几个高层次结构似乎分别对物体和面孔的遮挡具有不变性，并且几个运动区域似乎对物体恒常性进行编码。关于非模态完成时间的各种结果暗示了前馈、循环和反馈过程的混合。我们讨论了被遮挡物体的不可见部分是否被表征为好像它们是可见的，这与高层次表征相反。虽然关于非模态完成仍有许多问题，但这篇综述概述了迄今为止报道的神经影像学发现，总结了计算模型的一些见解，并将其与模态完成等其他知觉完成过程的研究联系起来。总体而言，有人认为非模态完成是处理各种类型不完整视网膜信息的解决方案，并且高度依赖于刺激的复杂性和显著性，因此也产生了各种观察到的神经模式。
