記憶與記憶障礙

Memory and Memory Disorders

10.29819/ANT.200712.0010

邱銘章(Ming-Jang Chiu)

內隱記憶 ； 外顯記憶 ； 錯誤記憶 ； 年齡相關記憶障礙 ； 記憶障礙 ； Implicit memory ； Explicit memory ； False memory ； Age-associated memory impairment ； Memory disorder

Acta Neurologica Taiwanica

16卷4期（2007 / 12 / 01）

242 - 250

繁體中文

記憶是重新建構的過程，依覺知程度分外顯與內隱記憶。外顯爲有意識的回想或知識，依情境的有無分成事件與語意記憶。事件是個人過去的經驗，語意則是普遍性知識。內隱是促發、程序記憶或技能。任何片刻大腦所保有待處理或轉換的「線上」訊息，就是工作記憶。預想記憶要在未來某個時間點完成某件事。過度依賴要旨記憶會產生錯誤記憶。情緒的鼓動會影響編碼與固化而加強記憶。外顯記憶依賴內側顯葉與前額葉來完成；內隱記憶的促發直接作用在大腦皮質上；動作或技能的學習與基底核關係密切；小腦則對古典制約及複雜運動的學習很重要。年齡增長導致的記憶衰退，主要來自執行功能，尤其是工作記憶或注意力系統速度與容量的退化有關。「年齡相關之記憶障礙」可能是正常的老化，「輕度知能障礙」可能是臨床前的失智症。阿茲海默症是記憶障礙的最常見病因，先出現事件記憶的困難；在額顯葉型失智症，語意記憶的障礙較顯著，事件記憶反而維持較好；在路易氏體失智症，工作記憶的缺損最明顯。

Memory is a reconstructive process classified as explicit and implicit memory by level of awareness. Explicit memory is a conscious recollection of either episodic or semantic memory. Episodic memory is from personal experience and is context-specific while semantic memory refers to general knowledge. Implicit memory is from priming, procedure memory or skills. On-line message held by the brain is the working memory. Prospective memory is about something to be done in the future. Over-reliance on gist memory brings in false memory. The stirring of emotion has effect on encoding and consolidation. Explicit memory depends on medial temporal and prefrontal lobes. Priming impinges directly on cerebral cortex. Procedure memory or motor skills are closely related to basal ganglia. Cerebellum plays an important role in classical conditioning and complex motor learning. Age effect on memory is mainly from decreased speed and capacity of the central executive function. Age-associated memory impairment could be normal aging while mild cognitive impairment could be preclinical dementia. Alzheimer's disease starts with episodic memory, frontotemporal dementia defects semantic memory and Lewy's body dementia impairs working memory.