Gredebäck Gustaf, von Hofsten Claes
Department of Psychology Uppsala University Uppsala, Sweden.
Infancy. 2004 Sep;6(2):165-184. doi: 10.1207/s15327078in0602_2. Epub 2004 Sep 1.
Infants' ability to track temporarily occluded objects that moved on circular trajectories was investigated in 20 infants using a longitudinal design. They were first seen at 6 months and then every 2nd month until the end of their 1st year. Infants were presented with occlusion events covering 20% of the target's trajectory (effective occlusion interval ranged from 500-4,000 msec). Gaze was measured using an ASL 504 infrared eye-tracking system. Results effectively demonstrate that infants from 6 months of age can represent the spatiotemporal dynamics of occluded objects. Infants at all ages tested were able to predict, under certain conditions, when and where the object would reappear after occlusion. They moved gaze accurately to the position where the object was going to reappear and scaled their timing to the current occlusion duration. The average rate of predictive gaze crossings increased with occlusion duration. These results are discussed as a 2-factor process. Successful predictions are dependent on strong representations, themselves dependent on the richness of information available during encoding and graded representations.
采用纵向设计，对20名婴儿追踪沿圆形轨迹移动的暂时被遮挡物体的能力进行了研究。他们在6个月大时首次接受观察，之后每隔两个月观察一次，直至满一岁。向婴儿呈现的遮挡事件覆盖目标轨迹的20%（有效遮挡间隔为500 - 4000毫秒）。使用ASL 504红外眼动追踪系统测量注视情况。结果有力地表明，6个月大的婴儿能够表征被遮挡物体的时空动态。所有接受测试的年龄段的婴儿在某些条件下都能够预测物体在遮挡后何时何地会重新出现。他们将目光准确地移到物体即将重新出现的位置，并根据当前的遮挡持续时间调整自己的时间把握。预测性注视穿越的平均速率随遮挡持续时间的增加而提高。这些结果被作为一个双因素过程进行讨论。成功的预测依赖于强大的表征，而强大的表征本身又依赖于编码过程中可用信息的丰富程度以及分级表征。
