Montoya Alonso, Pelletier Marc, Menear Matthew, Duplessis Elisabeth, Richer François, Lepage Martin
Douglas Hospital Research Centre, Department of Psychiatry, McGill University, Canada.
Neuropsychologia. 2006;44(10):1984-94. doi: 10.1016/j.neuropsychologia.2006.01.015. Epub 2006 Jun 23.
Memory dysfunction is an important feature in the clinical presentation of Huntington's disease (HD) and may precede the onset of motor symptoms. Although several studies have contributed to the quantitative and qualitative description of memory impairments in HD, the characterization of episodic memory impairments has varied considerably. Whereas most studies report significant impairments on free recall tests, performance on recognition tests has been considerably more variable, ranging from normal to markedly deficient. This absence of a well-established recognition memory deficit has led some investigators to attribute the memory deficits in HD to a retrieval-based episodic memory impairment. We felt that a quantitative review of the literature was needed to better characterize these episodic memory impairments. We conducted a meta-analysis to assess the magnitude of the recognition memory deficit in HD and to examine it in relation to the known deficit in recall. Memory data were provided by 544 symptomatic HD patients, 224 presymptomatic gene-carriers, and 963 control subjects. The overall group comparison between symptomatic patients and controls yielded effect sizes of d=1.95 for free recall and d=1.73 for recognition. We split the symptomatic group into two subgroups based on their mental status (mild and moderate/severe dementia) and both showed significant deficits in recall and recognition memory, though recall was more impaired than recognition in the mild dementia subgroup. Only slight memory impairment was observed in the presymptomatic subjects. The results show that deficits in recognition memory must be accounted for in future models of memory impairment in HD.
记忆功能障碍是亨廷顿舞蹈症（HD）临床表现的一个重要特征，且可能先于运动症状出现。尽管多项研究对HD患者记忆损害的定量和定性描述有所贡献，但情景记忆损害的特征却有很大差异。大多数研究报告称，在自由回忆测试中存在显著损害，而在识别测试中的表现则差异更大，从正常到明显缺陷不等。由于缺乏公认的识别记忆缺陷，一些研究人员将HD患者的记忆缺陷归因于基于检索的情景记忆损害。我们认为需要对文献进行定量综述，以更好地描述这些情景记忆损害。我们进行了一项荟萃分析，以评估HD患者识别记忆缺陷的程度，并将其与已知的回忆缺陷进行比较。记忆数据来自544名有症状的HD患者、224名症状前基因携带者和963名对照受试者。有症状患者与对照受试者的总体组间比较得出，自由回忆的效应量为d = 1.95，识别的效应量为d = 1.73。我们根据有症状组的精神状态将其分为两个亚组（轻度和中度/重度痴呆），两个亚组在回忆和识别记忆方面均显示出显著缺陷，尽管在轻度痴呆亚组中，回忆比识别受损更严重。在症状前受试者中仅观察到轻微的记忆损害。结果表明，在未来HD记忆损害模型中必须考虑识别记忆缺陷。
