Falconbridge Michael, Hewitt Kassandra, Haille Julia, Badcock David R, Edwards Mark
The University of Western Australia, Australia.
The Australian National University, Australia.
Iperception. 2022 Sep 7;13(5):20416695221118111. doi: 10.1177/20416695221118111. eCollection 2022 Sep-Oct.
Induced motion is the illusory motion of a target away from the direction of motion of the unattended background. If it is a result of assigning background motion to self-motion and judging target motion relative to the scene as suggested by the flow parsing hypothesis then the effect must be mediated in higher levels of the visual motion pathway where self-motion is assessed. We provide evidence for a high-level mechanism in two broad ways. Firstly, we show that the effect is insensitive to a set of low-level spatial aspects of the scene, namely, the spatial arrangement, the spatial frequency content and the orientation content of the background relative to the target. Secondly, we show that the effect is the same whether the target and background are composed of the same kind of local elements-one-dimensional (1D) or two-dimensional (2D)-or one is composed of one, and the other composed of the other. The latter finding is significant because 1D and 2D local elements are integrated by two different mechanisms so the induced motion effect is likely to be mediated in a visual motion processing area that follows the two separate integration mechanisms. Area medial superior temporal in monkeys and the equivalent in humans is suggested as a viable site. We present a simple flow-parsing-inspired model and demonstrate a good fit to our data and to data from a previous induced motion study.
诱导运动是指目标朝着与未被关注的背景运动方向相反的方向产生的虚幻运动。如果这是将背景运动归因于自身运动，并根据流动解析假说判断目标相对于场景的运动的结果，那么这种效应必定是在视觉运动通路中评估自身运动的较高层次上介导的。我们从两个主要方面为一种高层次机制提供了证据。首先，我们表明这种效应对于场景的一组低层次空间特征不敏感，即背景相对于目标的空间排列、空间频率内容和方向内容。其次，我们表明无论目标和背景是由同一种局部元素——一维（1D）或二维（2D）——组成，还是一个由一种组成而另一个由另一种组成，效应都是相同的。后一个发现很重要，因为1D和2D局部元素是通过两种不同机制整合的，所以诱导运动效应很可能是在遵循这两种不同整合机制的视觉运动处理区域中介导的。猴子的内侧颞上区以及人类的相应区域被认为是一个可能的部位。我们提出了一个受流动解析启发的简单模型，并证明它与我们的数据以及先前一项诱导运动研究的数据拟合良好。
