Perception in Action Research Centre & School of Psychological Sciences, Macquarie University, 16 University Ave, North Ryde, NSW, 2109, Australia; Laboratory of Brain and Cognition, 10 Center Drive, 10/4C104, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, 20892, USA.
Perception in Action Research Centre & School of Psychological Sciences, Macquarie University, 16 University Ave, North Ryde, NSW, 2109, Australia; School of Psychology, University of Sydney, Sydney, NSW, Australia.
Cortex. 2022 Aug;153:66-86. doi: 10.1016/j.cortex.2022.04.009. Epub 2022 Apr 26.
Objects disappearing briefly from sight due to occlusion is an inevitable occurrence in everyday life. Yet we generally have a strong experience that occluded objects continue to exist, despite the fact that they objectively disappear. This indicates that neural object representations must be maintained during dynamic occlusion. However, it is unclear what the nature of such representation is and in particular whether it is perception-like or more abstract, for example, reflecting limited features such as position or movement direction only. In this study, we address this question by examining how different object features such as object shape, luminance, and position are represented in the brain when a moving object is dynamically occluded. We apply multivariate decoding methods to Magnetoencephalography (MEG) data to track how object representations unfold over time. Our methods allow us to contrast the representations of multiple object features during occlusion and enable us to compare the neural responses evoked by visible and occluded objects. The results show that object position information is represented during occlusion to a limited extent while object identity features are not maintained through the period of occlusion. Together, this suggests that the nature of object representations during dynamic occlusion is different from visual representations during perception.
由于遮挡而导致物体短暂地从视线中消失是日常生活中不可避免的现象。然而，我们通常有一种强烈的体验，即尽管物体客观上消失了，但它们仍然继续存在。这表明，在动态遮挡期间，神经物体表示必须被维持。然而，目前尚不清楚这种表示的性质是什么，特别是它是类似于感知的还是更抽象的，例如，仅反映位置或运动方向等有限的特征。在这项研究中，我们通过检查当移动物体被动态遮挡时，大脑中物体的形状、亮度和位置等不同特征是如何被表示的，来解决这个问题。我们应用多元解码方法对脑磁图 (MEG) 数据进行分析，以跟踪物体表示如何随时间展开。我们的方法允许我们在遮挡期间对比多个物体特征的表示，并使我们能够比较可见和遮挡物体引起的神经反应。结果表明，在遮挡期间，物体位置信息在一定程度上被表示，而物体身份特征在遮挡期间则无法维持。总的来说，这表明在动态遮挡期间物体表示的性质不同于感知期间的视觉表示。
