Stark Craig E L, Bayley Peter J, Squire Larry R
Departments of Psychological and Brain Sciences and of Neuroscience, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Learn Mem. 2002 Sep-Oct;9(5):238-42. doi: 10.1101/lm.51802.
The formation of new associations between items is critical for establishing episodic memories. It has been suggested that the hippocampus is essential for creating such associations but is not involved, or is much less involved, in memory for single items. In Experiment 1, we tested controls and amnesic patients with bilateral lesions thought to be limited primarily to the hippocampal region in both single-item and associative recognition memory tasks. In the single-item task, a conventional recognition memory task was administered in which participants studied either houses or faces and were tested for their ability to recognize the individual items. In the associative task, participants studied paired pictures of houses and faces with instructions that encouraged associating the two stimuli, and were tested for their ability to recognize the specific pairings that were presented at study. Like the controls, the amnesic patients performed more poorly on the associative task. Relative to the controls, the amnesic patients were impaired to a similar extent on the single-item and associative tasks. In Experiment 2, the performance of the amnesic patients was improved by increasing the number of presentations of the study lists (eight presentations instead of one). On both the single-item and associative tests, the performance of the amnesic patients after eight presentations was now identical to the performance of the controls who had been given only one presentation of the study list. Thus, the associative condition was not disproportionally difficult for the amnesic patients. These results are consistent with the idea that the hippocampus is similarly involved in single-item and associative memory.
项目之间新关联的形成对于建立情景记忆至关重要。有人提出，海马体对于创建此类关联至关重要，但在单个项目的记忆中不涉及或涉及程度要小得多。在实验1中，我们在单项和关联识别记忆任务中测试了对照组以及被认为主要局限于双侧海马区损伤的失忆症患者。在单项任务中，实施了一项传统的识别记忆任务，参与者学习房屋或面孔，然后测试他们识别单个项目的能力。在关联任务中，参与者学习房屋和面孔的配对图片，并按照鼓励将两种刺激联系起来的指示进行学习，然后测试他们识别学习时呈现的特定配对的能力。与对照组一样，失忆症患者在关联任务中的表现更差。相对于对照组，失忆症患者在单项和关联任务中的受损程度相似。在实验2中，通过增加学习列表的呈现次数（八次呈现而不是一次），失忆症患者的表现得到了改善。在单项和关联测试中，失忆症患者在八次呈现后的表现现在与只接受过一次学习列表呈现的对照组的表现相同。因此，关联条件对失忆症患者来说并没有特别困难。这些结果与海马体在单项和关联记忆中同样起作用的观点一致。
