早期阿茲海默症患者在訊息處理速度與工作記憶表現初探

The Performance on Information Processing Speed and Working Memory of Patients with mild Alzheimer's Disease

陳恩誠(En-Cheng Chen)

指導教授 ： 楊建銘 ； 洪福建

中原大學/理學院/心理學研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700061

摘要

研究目的：目前臨床上對阿茲海默症診斷使用的認知評估工具，例如MMSE與CASI等，普遍會受到教育程度的影響。過去的研究顯示早期阿茲海默症在工作記憶、訊息處理速度，與學習記憶為其主要行為表現障礙，其中訊息處理速度與工作記憶受到教育程度的影響較低。本研究的目的在於透過較少教育因素干擾之訊息處理速度、工作記憶的評估，探索早期失智症老人的認知表現。並運用這些所選出的認知評估工具，找出對早期失智症最佳的預測函數。同時，研究並比較不同教育程度的失智症族群中，預測因子對診斷組的區辨力差異情況，並且與簡短智能評估（MMSE）的區辨力進行探討比較。
研究方法：研究受試者包含28名患有輕度阿茲海默症的患者，以及28名正常控制組的老人。每一名受試者根據DSM-IV的準則診斷，並以CDR作為其病程的判斷依據。每一個研究組別內以教育程度六年為分界區隔，大於六年教育年數者為中高教育組，不超過六年者為低教育組別。每一名受試者都接受相關的神經心理測驗與MMSE。本研究所選用的神經心理測驗，包含數字符號替代、視覺記憶廣度、聽覺記憶廣度、Color Trails Test，以及魏氏記憶量表的字詞學習測驗。研究結果採用多變異數分析來探索阿茲海默症組與正常組的表現差異，以及使用區辨分析對診斷組進行區辨函數統計分析。
研究結果：變異數分析的結果顯示早期阿茲海默症組的受試者在所有神經心理測驗與MMSE的表現，顯著低於正常組的健康老人。在研究中區辨分析的結果發現Color Trails Test 和魏氏記憶量表的字詞學習II（延宕記憶）兩個研究變項是較佳的區辨因子。
研究結論：本研究的結果顯示早期阿茲海默症患者在訊息處理速度、工作記憶與學習記憶的表現，均顯著低於正常組的老人。對於臨床上使用建議以MMSE搭配CTT作為對阿茲海默症的區辨預測，比目前臨床上單獨使用的MMSE有更好的區辨力。

關鍵字

阿茲海默症 ； 訊息處理速度 ； 工作記憶

並列摘要

Background and Purpose：Early detection of senile dementia has important clinical value. Education had a strong effect on the conventional cognitive screening test, such as Cognitive Abilities Screening Instrument and Mini-Mental State Examination. Previous research showed that information processing speed, working memory, and recent memory had most prominent declines in the early stage of dementia, and were less influenced by education. The purposes of this study are (1) to exam the performance on information processing speed and working memory in Alzheimer's disease（AD） patients with different educational levels, (2) to find the cognitive tests that can find the best prediction the diagnosis of AD, and (3) to compare the discriminative power in different educational levels of patients with the diagnosis of dementia .
Method： Twenty-eight who were patients diagnosed with mild AD and 28 age-matched control subjects participated in the study. Clinical diagnosis of dementia was made by consensus committee using DSM-IV criteria. Severity of dementia was staged using the Clinical Dementia Rating Scale (CDR). These participants were involved in schooling in the low education group for six years or less and for more than six years in the high education group. They underwent neuropsychological evaluations using the Color Trails Test（CTT）, Digit Symbol, Spatial Span（SS）, Digit Span（DS）, Word List subtest of the Weschler Memory Scale-III, and MMSE. Two by two two-way ANOVA were conducted to compare the performance between normal control and dementia patients, and between patients with low verse high educational levels. Discriminate analyze were also conducted to will evaluate how well a brief battery of tests could discriminate mildly demented persons from normal aged.
Results： The results indicate that the patients with AD performed significantly more poorly than normal controls on all the neuropsychological tests as well as MMSE. Education did not show an effect on most of the neuropsychological tests for patient with early stage of AD. The discriminate analysis revealed that the CTT, Word Lists II are the better predictive tests in the Alzheimer’s disease..
Conclusion：The findings suggest that information processing and working memory are impaired at early stage of AD. MMSE and CTT showed better predictive power in the differentiation of AD from normal participants than the MMSE.

並列關鍵字

Alzheimer’s Disease ； Working Memory ； Information Processing Speed

參考文獻

徐榮隆、陳威宏、邱浩彰、沈幸梅（民89）。不同時期失智症之認知功能。台灣醫學。4，371-378。

張本聖（民89）。失智症前兆研究結果與意義。應用心理學。8，3-6。

劉景寬、戴志達、林瑞泰、賴秋蓮（民89）。臺灣失智症的流行病學 。應用心理研究。7，157-169。

郭乃文、劉秀枝、王佩芳、廖光淦、甄瑞興、林恭平、陳祖裕、徐道昌（民77）。「簡短式智能評估」之中文施測與常模建立。復建醫學雜誌。16，52-59。

Beata, L., & Lars, B. (1997). Encoding–retrieval Interactions in mild Alzheimer's Disease: The Role of Access to Categorical Information. Brain and Cognition, 34(2), 274-286.