Quinette Peggy, Guillery Bérengère, Desgranges Béatrice, de la Sayette Vincent, Viader Fausto, Eustache Francis
Inserm E0218-Université de Caen, Laboratoire de Neuropsychologie, CHU Côte de Nacre, 14033 Cannes Cedex, France.
Brain. 2003 Sep;126(Pt 9):1917-34. doi: 10.1093/brain/awg201. Epub 2003 Jul 22.
Transient global amnesia (TGA) is usually considered to produce a profound impairment of long-term episodic memory, while at the same time sparing working memory. However, this neuropsychological dissociation has rarely been examined in detail. While a few studies have assessed some components of working memory in TGA, the results that have been obtained are far from conclusive. To clarify this issue, we carried out a comprehensive investigation of working memory in 10 patients during a TGA attack. In the first study, we report the results from three patients examined with a battery of neuropsychological tests designed to assess each of the three subcomponents of Baddeley's model of working memory. In a second study, seven different patients underwent neuropsychological investigations that focused specifically on the central executive system, using a protocol derived from a study by Miyake and colleagues. Our findings showed that subcomponents of working memory, such as the phonological loop and visuo-spatial sketch pad, were spared in TGA patients. Specific executive functions that entailed inhibitory control, dual task performance, updating and shifting mechanisms were also found to be normal. However, we found significantly impaired performance for the Brown-Peterson test, and that TGA patients were significantly impaired in the recollection of their episodic memories. They also made reduced numbers of 'remember' compared with 'know' judgments in the episodic memory test several days after TGA. On the basis of our findings, it would appear that the episodic memory deficit during TGA is not related to elementary aspects of executive functioning. Our data also highlight the nature of the cognitive mechanisms involved in the Brown-Peterson task, which may well depend on long-term memory (such as the process of semantic encoding). Lastly, the selective deficit in recollective episodic memories observed in TGA may be principally related to medial temporal lobe abnormalities that have been reported in this syndrome.
短暂性全面性遗忘症（TGA）通常被认为会导致长期情景记忆严重受损，而工作记忆则不受影响。然而，这种神经心理学上的分离现象很少得到详细研究。虽然有一些研究评估了TGA患者工作记忆的某些组成部分，但所得结果远未得出定论。为了阐明这个问题，我们对10例TGA发作期患者的工作记忆进行了全面调查。在第一项研究中，我们报告了对3例患者进行一系列神经心理学测试的结果，这些测试旨在评估巴德利工作记忆模型的三个子成分。在第二项研究中，另外7例患者接受了专门针对中央执行系统的神经心理学调查，采用的是宫下及其同事的一项研究所使用的方案。我们的研究结果表明，TGA患者的工作记忆子成分，如语音回路和视觉空间画板，未受影响。还发现需要抑制控制、双任务执行、更新和转换机制的特定执行功能也正常。然而，我们发现布朗-彼得森测试的表现明显受损，TGA患者的情景记忆回忆也明显受损。在TGA发作几天后的情景记忆测试中，他们做出的“记得”判断与“知道”判断相比数量减少。根据我们的研究结果，TGA期间的情景记忆缺陷似乎与执行功能的基本方面无关。我们的数据还突出了布朗-彼得森任务所涉及的认知机制的性质，这很可能取决于长期记忆（如语义编码过程）。最后，TGA中观察到的情景记忆回忆的选择性缺陷可能主要与该综合征中报道的内侧颞叶异常有关。
