Braun Alisa, Sweeny Timothy D
Department of Psychology, University of Denver, United States.
Department of Psychology, University of Denver, United States.
Vision Res. 2019 Mar;156:17-27. doi: 10.1016/j.visres.2019.01.002. Epub 2019 Jan 23.
While object perception may feel instantaneous, it is an iterative process in which information is accumulated until ambiguity about identity and location is resolved. In theory, awareness of an object should depend on how efficiently this process occurs. Therefore, objects with inherently weak visual representations should be more susceptible to perceptual disruption. We tested this hypothesis by examining the perception of aspect ratio, a 2D feature of shapes with anisotropic representation (circular shapes are less robustly represented than elongated shapes in high-level visual areas). Observers viewed a target shape shown for 20-ms within an array of ellipses. The target, which varied from flat to tall, was either masked or unmasked. Observers indicated the target's aspect ratio and if it was visible. Observers reported seeing elongated shapes far more often than circular shapes, but only on trials with object-substitution masking. This effect replicated across five control experiments, even though the shapes were identical in basic image attributes (e.g., contrast, area). Our findings demonstrate that shapes with extreme aspect ratios are more readily available to awareness than shapes with ambiguous dimensionality. More generally, this work supports theories of object processing which suggest that strength of visual representation gates access to awareness.
虽然物体感知可能感觉是瞬间完成的，但它是一个迭代过程，在这个过程中信息不断积累，直到关于物体身份和位置的模糊性得到解决。理论上，对物体的意识应该取决于这个过程发生的效率。因此，具有固有较弱视觉表征的物体应该更容易受到感知干扰。我们通过研究长宽比的感知来验证这一假设，长宽比是形状的二维特征，具有各向异性表征（在高级视觉区域，圆形形状的表征不如细长形状稳健）。观察者在一系列椭圆阵列中观看呈现20毫秒的目标形状。目标形状从扁平到细长变化，要么被掩蔽，要么未被掩蔽。观察者指出目标的长宽比以及它是否可见。观察者报告说，他们看到细长形状的频率远高于圆形形状，但仅在物体替代掩蔽的试验中如此。即使形状在基本图像属性（如对比度、面积）上相同，这一效应在五个对照实验中都得到了重复。我们的研究结果表明，与维度模糊的形状相比，长宽比极端的形状更容易被意识到。更普遍地说，这项工作支持了物体加工理论，该理论表明视觉表征的强度控制着进入意识的通道。
