健康与遗传心理学研究室知识库

    按照经典的陈述性记忆存储理论，存储记忆信息的区域与最初对外界信息进行加工和编码的区域相同。这一理论近年来受到了挑战。如一些研究者发现，提取颜色信息并不是总能激活颜色知觉区。但我们认为，这种现象可以用图形特征和语义特征分别贮存的观点解释。本研究对这种观点进行了验证。
    方法:应用事件相关功能磁共振成像技术观察了6名被试在颜色知觉和颜色信息提取过程中的脑活动特点。提取任务要求被试在熟练学习颜色和运动联系的条件下间接回忆学习材料的颜色特征。
结果:颜色知觉激活V4，而颜色回忆过程主要激活左侧梭状回后部，激活区倾向于分为前后两个亚区。其中后部区域的位置与V4相同，该区域达到最大激活的时间约比前部区域晚2秒。
结论:颜色的图形特征主要贮存于左侧V4区，语义特征贮存在V4的前部。这些结果表明，尽管陈述性记忆中图形和语义信息密切相关，但被分别存储于解音U上分离的脑结构内。

    According to the classical theory of storage of declarative memory, memory trace is stored in the same network that mediates information processing and encoding. However, this theory has been challenged in recent years.  For example, several neuroimaging studies show that retrieval of color information does not always activates brain areas  engaged during color perception.   We argued that this phenomenon could be explained by the view of differential storage of pictorial and  semantic information.  The present study was designed to test our argument.
Methods: Event-related fMRI was used to investigate the activation of cerebral cortex during color perception and color retrieval in 6 normal right-handed volunteers. In the retrieval task, the subjects were asked to recall the color of learned materials, following repeatedly learning the arbitrary associations of color and moving direction.
    Results:  V4 in the posterior fusiform gyrus was significantly activated during color perception, whereas recall of color information activated left fusiform gyrus, which was organized into two distinct areas, one was more anterior than the other. The posterior one was at the same location of V4.  Peak activation in this area was about two seconds later than that in the anterior area.
    Conclusion:  While the pictorial aspect of color information is stored in left V4，the semantic aspect is stored in an area anterior to the V4.  These results suggest that pictorial and semantic information in declarative memory is closely related but separately stored in different brain areas.