Sport and Health Sciences, University of Exeter , Exeter, UK.
School of Social Sciences,Psychology, Heriot-Watt University , Edinburgh, UK.
Neurocase. 2020 Oct;26(5):277-284. doi: 10.1080/13554794.2020.1800748. Epub 2020 Aug 17.
The size-weight illusion is a perceptual illusion where smaller objects are judged as heavier than equally weighted larger objects. A previous informal report suggests that visual form agnosic patient DF does not experience the size-weight illusion when vision is the only available cue to object size. We tested this experimentally, comparing the magnitudes of DF's visual, kinesthetic and visual-kinesthetic size-weight illusions to those of 28 similarly-aged controls. A modified t-test found that DF's visual size-weight illusion was significantly smaller than that of controls (z = -1.7). A test of simple dissociation based on the Revised Standardized Difference Test found that the discrepancy between the magnitude of DF's visual and kinesthetic size-weight illusions was not significantly different from that of controls (z = -1.054), thereby failing to establish a dissociation between the visual and kinesthetic conditions. These results are consistent with previous suggestions that visual form agnosia, following ventral visual stream damage, is associated with an abnormally reduced size-weight illusion. The results, however, do not confirm that this reduction is specific to the use of visual size cues to predict object weight, rather than reflecting more general changes in the processing of object size cues or in the use of predictive strategies for lifting.
大小重量错觉是一种知觉错觉，其中较小的物体被判断为比同等重量的较大物体更重。之前的一份非正式报告表明，当视觉是唯一可用的物体大小线索时，视觉形式认知障碍患者 DF 不会经历大小重量错觉。我们通过实验对此进行了测试，将 DF 的视觉、动觉和视觉动觉大小重量错觉的大小与 28 名年龄相仿的对照组进行了比较。修正后的 t 检验发现，DF 的视觉大小重量错觉明显小于对照组（z=-1.7）。基于修订后的标准化差异检验的简单分离测试发现，DF 的视觉和动觉大小重量错觉大小之间的差异与对照组没有显著差异（z=-1.054），因此未能在视觉和动觉条件之间建立分离。这些结果与之前的建议一致，即腹侧视觉流损伤后的视觉形式认知障碍与异常减小的大小重量错觉有关。然而，这些结果并不能证实这种减少是特定于使用视觉大小线索来预测物体重量的，而不是反映了物体大小线索处理或用于提升的预测策略的更普遍变化。
