INSERM U 751, Marseille, France.
Cortex. 2012 Nov-Dec;48(10):1310-9. doi: 10.1016/j.cortex.2011.09.002. Epub 2011 Sep 14.
The concept of amnestic mild cognitive impairment (aMCI) concerns a population of older individuals at high risk of developing probable Alzheimer's disease. Although anterograde memory deficits have been largely documented in patients with aMCI, little is known about the integrity of their autobiographical memory (AuM). This study aimed at evaluating AuM in aMCI individuals and at investigating whether their ability to retrieve AuMs varied as a function of whether the tests used required recognition or effortful retrieval processes. Fourteen aMCI patients and 14 matched controls underwent a standard neuropsychological evaluation and an extensive autobiographical assessment. AuM was explored using verbal material, the Autobiographical Memory Interview, and a visual task of personal photographs. Together, these tests tapped the semantic and episodic components of AuM and different cognitive processes involved in retrieval (recall and recognition). Results indicate that AuM is altered in aMCI patients. This impairment affects both episodic and semantic components of AuM, and is characterized by a general difficulty in recollecting personal episodes covering the entire lifespan, along with a loss of recognition of recently experienced episodes. Furthermore, recollection of personal episodes was correlated with scores on tests requiring retrieval abilities, while recognition of familiar photographs was correlated with scores on tests assessing encoding/storage of new information. Results suggest that the AuM deficit in aMCI patients may result from the combination of two mechanisms, an anterograde memory impairment impeding the storage of newly experienced events, and a global alteration of recollection affecting the recall of AuM covering all periods of life. Alteration of these processes may possibly be related to the progression and distribution of the neuropathological lesions in medial temporal and frontal lobe structures found in Alzheimer's disease.
遗忘型轻度认知障碍(aMCI)的概念涉及到一群处于发展为可能的阿尔茨海默病高风险的老年个体。尽管在 aMCI 患者中已经广泛记录了顺行性记忆缺陷,但他们自传体记忆(AuM)的完整性知之甚少。本研究旨在评估 aMCI 个体的 AuM,并研究他们检索 AuM 的能力是否因测试是否需要识别或努力检索过程而有所不同。14 名 aMCI 患者和 14 名匹配的对照者接受了标准神经心理学评估和广泛的自传体评估。使用言语材料、自传记忆访谈和个人照片的视觉任务来探索 AuM。这些测试共同挖掘了 AuM 的语义和情节成分以及检索(回忆和识别)中涉及的不同认知过程。结果表明,aMCI 患者的 AuM 发生了改变。这种损伤影响了 AuM 的情节和语义成分,其特征是普遍难以回忆个人生活中的整个情节,同时也失去了对最近经历的情节的识别。此外,个人情节的回忆与需要检索能力的测试得分相关,而熟悉照片的识别与评估新信息编码/存储的测试得分相关。结果表明,aMCI 患者的 AuM 缺陷可能是由于两种机制的结合造成的,即顺行性记忆损伤阻碍了新经历事件的存储,以及全局回忆能力的改变影响了 AuM 的回忆,涵盖了生活的所有时期。这些过程的改变可能与阿尔茨海默病中发现的内侧颞叶和额叶结构的神经病理学损伤的进展和分布有关。