Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, 6500 HB, The Netherlands
Department of Vision and Cognition, Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, 1105 BA, The Netherlands.
J Neurosci. 2020 Nov 25;40(48):9250-9259. doi: 10.1523/JNEUROSCI.0438-20.2020. Epub 2020 Oct 21.
What is selected when attention is directed to a specific location of the visual field? Theories of object-based attention have suggested that when spatial attention is directed to part of an object, attention does not simply enhance the attended location but automatically spreads to enhance all locations that comprise the object. Here, we tested this hypothesis by reconstructing the distribution of attention from primary visual cortex (V1) population neuronal activity patterns in 24 human adults (17 female) using functional magnetic resonance imaging (fMRI) and population-based receptive field (prf) mapping. We find that attention spreads from a spatially cued location to the underlying object, and enhances all spatial locations that comprise the object. Importantly, this spreading was also evident when the object was not task relevant. These data suggest that attentional selection automatically operates at an object level, facilitating the reconstruction of coherent objects from fragmented representations in early visual cortex. Object perception is an astonishing feat of the visual system. When visual information about orientation, shape, and color enters through our eyes, it has yet to be integrated into a coherent representation of an object. But which visual features constitute a single object and which features belong to the background? The brain mechanisms underpinning object perception are yet to be understood. We now demonstrate that one candidate mechanism, the successive activation of all parts of an object, occurs in early visual cortex and results in a detailed representation of the object following Gestalt principles. Furthermore, our results suggest that object selection occurs automatically, without involving voluntary control.
当注意力被引导到视野的特定位置时，会选择什么？基于对象的注意理论表明，当空间注意力被引导到物体的一部分时，注意力不仅简单地增强了被注意的位置，而且还自动扩展以增强构成该物体的所有位置。在这里，我们通过使用功能磁共振成像 (fMRI) 和基于群体的感受野 (prf) 映射，从 24 名成年人（17 名女性）的初级视觉皮层 (V1) 群体神经元活动模式中重建注意力的分布来检验这一假设。我们发现注意力从空间提示位置扩展到基础对象，并增强了构成对象的所有空间位置。重要的是，即使对象与任务无关，这种扩展也很明显。这些数据表明，注意力自动在对象级别上进行选择，有助于从早期视觉皮层中碎片化的表示中重建连贯的对象。对象感知是视觉系统的一项惊人壮举。当有关方向、形状和颜色的视觉信息通过我们的眼睛进入时，它尚未被整合到对象的连贯表示中。但是哪些视觉特征构成一个单一的对象，哪些特征属于背景？支持对象感知的大脑机制仍有待理解。我们现在证明，一个候选机制，即对象的所有部分的连续激活，发生在早期视觉皮层中，并导致根据格式塔原则对对象进行详细表示。此外，我们的结果表明，对象选择是自动发生的，而不涉及自愿控制。
