Tao Weidong, Sun Hongjin
aDepartment of Psychology, School of Education, Zhanjiang Normal University, Zhanjiang, Guangdong bSchool of Psychology, Southwest University, Chongqing, China cDepartment of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Ontario, Canada.
Neuroreport. 2013 Nov 13;24(16):903-10. doi: 10.1097/WNR.0000000000000017.
The body inversion effect is the finding that inverted body posture pictures are more difficult to recognize than upright body posture pictures are. The present study reinvestigated the body inversion effect in human observers using behavioral and eye movement measures to explore whether the body inversion effect correlates with specific eye movement features. Results showed that body postures elicited a robust and stable body inversion effect in reaction time throughout the experimental sessions. Eye-tracking data showed that the body inversion effect was robust only in the first fixation duration, but not in the second fixation duration. The analysis of the regions of interest showed that most fixations were located in the upper body for both the upright and the inverted body postures. Compared with inverted body postures, the upright postures led to a shorter reaction time and a shorter first fixation duration, but a larger portion of time to fixate on the head region, suggesting that participants tended to use head as a reference point to process upright body postures. For both the behavioral and the eye movement measures, the body inversion effect was robust for biomechanically possible body postures. However, for biomechanically impossible body postures (with angular manipulation of two joints), the effect was mixed. Although the error rate failed to show the body inversion effect, the reaction time measure and most eye movement measures, however, showed a body inversion effect. Overall, these results suggested that upright body postures are processed in expertise recognition and are processed configurally by human observers.
身体倒置效应是指发现倒置的身体姿势图片比直立的身体姿势图片更难识别。本研究使用行为和眼动测量方法，对人类观察者的身体倒置效应进行了重新研究，以探讨身体倒置效应是否与特定的眼动特征相关。结果表明，在整个实验过程中，身体姿势在反应时间上引发了强大而稳定的身体倒置效应。眼动追踪数据显示，身体倒置效应仅在首次注视持续时间内显著，而在第二次注视持续时间内不显著。感兴趣区域的分析表明，对于直立和倒置的身体姿势，大多数注视点都位于上半身。与倒置的身体姿势相比,直立姿势导致反应时间和首次注视持续时间更短，但注视头部区域的时间比例更大，这表明参与者倾向于将头部作为处理直立身体姿势的参考点。对于行为和眼动测量，身体倒置效应在生物力学上可能的身体姿势中都很显著。然而，对于生物力学上不可能的身体姿势（两个关节有角度操作），结果则好坏参半。虽然错误率没有显示出身体倒置效应，但反应时间测量和大多数眼动测量都显示出身体倒置效应。总体而言，这些结果表明，直立的身体姿势在专业识别中得到处理，并且人类观察者以整体方式对其进行处理。
