Kosslyn S M, LeSueur L L, Dror I E, Gazzaniga M S
Harvard University, Cambridge, MA.
Neuropsychologia. 1993 Jul;31(7):675-86. doi: 10.1016/0028-3932(93)90139-q.
How do people recognize objects when they face in a novel lateral (left/right) orientation? The results of three experiments with a split-brain patient, who has a totally nonfunctional corpus callosum, demonstrate that the corpus callosum cannot play a critical role in allowing one to recognize mirror-reversed objects. First, both cerebral hemispheres could recognize mirror-reversed versions of pictures as accurately as the original renditions in an incidental memory task. Second, when asked to decide whether pictures faced the same way that they had originally, neither hemisphere performed better than chance in an incidental memory task--suggesting that the shape representations in the hemispheres do not specify lateral orientation. Third, neither hemisphere exhibited "priming" for lateral orientation, as assessed in an "object decision task", and only the left hemisphere exhibited priming for encoding the shape (independent of its lateral orientation).
当人们面对新颖的侧向（左/右）方向的物体时，是如何识别它们的呢？对一位胼胝体完全失去功能的裂脑患者进行的三项实验结果表明，胼胝体在使人识别镜像反转物体方面并不能起到关键作用。首先，在一项附带记忆任务中，两个大脑半球都能像识别原始图片一样准确地识别镜像反转的图片版本。其次，当被要求判断图片是否与最初呈现的方向一致时，在附带记忆任务中，两个半球的表现都不比随机猜测好——这表明半球中的形状表征并未明确侧向方向。第三，在一项“物体判断任务”中评估发现，两个半球都没有表现出对侧向方向的“启动效应”，只有左半球表现出对形状编码的启动效应（与侧向方向无关）。
