Pluchon C, Simonnet E, Bouche G, Hugon J, Gil R
Service de Neurologie, Unité de Neuropsychologie et Rééducation du Langage, Hôpital de la Milétrie, CHU de Poitiers, France.
Rev Neurol (Paris). 2006 Jun;162(6-7):713-20. doi: 10.1016/s0035-3787(06)75068-8.
The goal of our work is to study the most consolidated items of semantic memory in normal subjects and in patients with Alzheimer's disease (AD).
The first test is based on automatic recall of didactic knowledge. This test is made of 250 automatic verbal expressions exploring general knowledge. It as been validated according to age and cultural levels in 219 normal subjects (20-90 years old). Another simplified test called EVA including only 50 of the 250 previously chosen items was also used. The EVA scores found in a normal population have been classified by centilages according to age and cultural levels. The EVA was also tested in 20 patients with AD and the results compared with MMSE and "Pyramids and Palm Trees Test" (semantic memory testing).
The results reveal that the scores observed with the first test in a normal population with comparable cultural levels are correlated with age. EVA test scores found in control subjects show that the median value, for a same age group, is positively correlated with cultural levels. In patients with AD, scores for EVA test and MMSE are associated, the low results being linked to the severity of dementia. In addition, scores for EVA test and "Pyramids and Palm Trees Test" are also significantly correlated. Seven patients with mild dementia (MMSE>20) have abnormal scores for the "Pyramids and Palm Trees Test".
Our study confirms that changes linked to aging do not involve all aspects of cognition. The most consolidated items of semantic memory assessed by EVA test seem to resist at the beginning of AD but later decline similarly to the other items of semantic memory. Normal results for EVA tests do not imply that semantic memory is not affected in the early phases of AD. We propose this new test which assesses the semantic memory stock without involving an active process of recuperation. This test is not suitable for an early diagnosis of AD but could help to evaluate the severity of the disease during the evolution.
我们工作的目标是研究正常受试者和阿尔茨海默病（AD）患者语义记忆中最稳固的项目。
第一个测试基于对教学知识的自动回忆。该测试由250个探索常识的自动言语表达组成。它已根据年龄和文化水平在219名正常受试者（20 - 90岁）中得到验证。还使用了另一个简化测试，即EVA，它仅包含先前所选250个项目中的50个。在正常人群中发现的EVA分数已根据年龄和文化水平按百分位数进行分类。EVA也在20名AD患者中进行了测试，并将结果与简易精神状态检查表（MMSE）和“金字塔与棕榈树测试”（语义记忆测试）进行比较。
结果显示，在文化水平相当的正常人群中，第一次测试观察到的分数与年龄相关。在对照受试者中发现的EVA测试分数表明，对于同一年龄组，中位数与文化水平呈正相关。在AD患者中，EVA测试分数和MMSE分数相关，低分结果与痴呆严重程度相关。此外，EVA测试分数和“金字塔与棕榈树测试”分数也显著相关。7名轻度痴呆患者（MMSE>20）在“金字塔与棕榈树测试”中得分异常。
我们的研究证实，与衰老相关的变化并不涉及认知的所有方面。通过EVA测试评估的语义记忆中最稳固的项目在AD初期似乎具有抵抗力，但后来与语义记忆的其他项目一样下降。EVA测试结果正常并不意味着在AD早期语义记忆未受影响。我们提出了这个新测试，它在不涉及主动恢复过程的情况下评估语义记忆储备。该测试不适合AD的早期诊断，但有助于在疾病发展过程中评估疾病的严重程度。
