Hock H S, Smith L B, Escoffery L, Bates A, Field L
Mem Cognit. 1989 Jul;17(4):490-502. doi: 10.3758/bf03202623.
When presented a series of patterns inside a frame, subjects unintentionally retained information concerning the frame-relative location of the elements composing the patterns; they could use this superficial information to estimate the frequency with which the elements occurred at various locations within the frame. There were two aspects of the results that supported the hypothesis that this superficial element-location information was abstractively encoded and, therefore, retrievable independent of the patterns comprising the elements: (1) Correlations between actual and estimated frequency remained significant after the effects of pattern recall were partialled out, and (2) correlations were enhanced by assuming that the frequency estimate for each location was affected by the imprecise coding of position for elements falling in surrounding locations. Additional experiments indicated that an orienting task emphasizing pattern recall resulted in very inaccurate estimation of element-location frequency, and intentional instructions improved the precision of position coding for individual elements.
当向受试者呈现框架内的一系列图案时，他们会无意中保留有关构成图案的元素在框架内相对位置的信息；他们可以利用这些表面信息来估计元素在框架内各个位置出现的频率。结果有两个方面支持了这样一种假设，即这种表面的元素位置信息是通过抽象编码的，因此可以独立于构成元素的图案进行检索：（1）在排除图案回忆的影响后，实际频率与估计频率之间的相关性仍然显著；（2）假设每个位置的频率估计受周围位置元素位置编码不精确的影响，相关性会增强。额外的实验表明，强调图案回忆的定向任务会导致对元素位置频率的估计非常不准确，而有意的指令提高了单个元素位置编码的精度。
