逆行性遗忘、额叶与远期记忆的组织

RETROGRADE AMNESIA, FRONTAL LOBE, AND REMOTE MEMORY ORGANIZATION

通过对一例严重记忆障碍合并额叶损伤病人的逆行性遗忘的分析 ,对远期记忆的组织特点进行了探讨。被试的额叶功能受损较为明显。除顺行性遗忘外 ,患者的逆行性遗忘也较为严重。对病人进行的逆行性遗忘检测包括 :著名人物测验、著名事件、一般知识测验和自传性记忆测验等。被试对著名人物、著名事件的回忆和再认成绩、以及有关个人的情节和语义记忆成绩均较低 ,但没有典型的随时间下降的趋势 ,而是呈平直斜率 ;患者儿童期的自传性记忆和公众事件记忆也受损。这两个特点均与内侧颞叶 -间脑系统损伤的特点不同 。

This case study was to explore the role of frontal lobe in the organization of remote memory. The performance of a 64 year old patient (QCY) in various tasks, including famous person test, famous event test, general knowledge test, and autobiographical memory interview, was compared with the performance of five normal control subjects. MRI and PET imaging demonstrated that the lesions of QCY were in the bilateral frontal lobe, left diencephalon, and left parahippocampus. The Wisconsin card sorting test showed that QCY had higher response and preservative errors than the controls. Results in other tests showed that he had extensive anterograde amnesia and retrograde amnesia. QCY had deficits in recalling and recognizing the famous person and famous events. His episodic and semantic parts of autobiographical memory were impaired as well. The patterns of the retrograde amnesia of QCY were(1) his retrograde amnesia did not show a temporal gradient, but a flat gradient; (2) his memory of his childhood was impaired. These two characteristics were different from patterns shown by patients with lesions in the medial temporal lobe diencephalon system, indicating that the frontal lobe participated in the retrieval process of remote memory.