内在参照轴在图形再认中的作用

Shape recognition is among the basic skills to live in the complex environment. There are already a series of studies found interesting mental phenomena in shape recognition, such as mental rotation, which was also found in scene recognition and suggested that there would be common mechanisms in these two recognition processes. Recently, Mou and his colleagues (2008) found that scene recognition was not only viewpoint dependent but also intrinsic-orientation dependent. In our study, we applied their part recognition paradigm to shape recognition and investigated whether there was intrinsic orientation effect in shape recognition, and furthermore, we investigated the selection of the intrinsic axis in shape recognition. The results showed that a test shape divided from the learning direction and thus containing intrinsic axis was easier to recognize, relative to the test shape which was not divided from the learning direction. The results also showed that a test shape presented from the viewing direction was easier to recognize than from other direction. Furthermore, after we added an oblique rectangular background to the learning shape, the results showed that participants chose the prolate axis of the rectangular background as their learning direction and thus the direction of the intrinsic axis. This result suggested that the direction of the intrinsic axis can be separated from the viewing direction, and background can play a decisive role in the selection of intrinsic axis.

图形再认是人类在复杂环境中赖以生存的一项基本能力。已有很多研究发现图形再认中存在的心理旋转等重要心理现象；对场景再认的研究也发现了类似的研究结果，说明这两个心理过程可能有相同的机制。而Mou, Fan等人（2008）发现，场景再认中不仅存在视点依赖效应，还存在内在轴效应，这个研究为图形再认研究提供了启发和新的研究范式。本研究采用牟等人（2008）部分再认的范式，考察了图形记忆中是否存在内在轴效应这一问题，并在此基础上，进一步考察图形表征中的内在轴方向的选择机制。本研究可以得出如下主要结论： 1．图形再认是依赖于内在轴方向的。当测试图形是从学习方向进行切分时，由于测试图形包含了内在轴，这时被试再认这个图形比再认未包含内在轴的测试图形容易； 2．图形再认是依赖于观察视点的，当测试图形是从原学习图形的观察方向呈现时比从非观察方向呈现时容易再认。这说明在表征图形本身的同时，观察者自身相对于内在参照系的位置也在图形记忆中进行了表征。 3．学习图形时内在轴的方向是可以不同与观察方向的，背景可以改变被试的学习方向，将被试的学习方向与观察方向进行分离，从而将观察方向与内在轴方向进行分离。 4．从本研究结果，我们可以进一步推测图形再认的心理过程：被试需要先确定出测试图形中的内在轴方向，然后将测试图形中的内在轴方向与记忆中原学习图形的内在轴方向进行对正，从而判断测试图形是否是之前学习过的图形。