Pike K E, Rowe C C, Moss S A, Savage G
School of Psychology, Psychiatry and Psychological Medicine.
Department of Nuclear Medicine.
Neuropsychology. 2008 Nov;22(6):718-728. doi: 10.1037/a0013050.
Mild cognitive impairment (MCI) is associated with increased risk of developing Alzheimer's disease (AD), but up to 40% of cases do not develop AD. Examining a case's specific memory profile may help distinguish which MCI cases will progress to AD: An encoding profile is suggestive of incipient AD, whereas a retrieval profile suggests an alternative etiology. Paired associate learning (PAL) tasks are sensitive for preclinical and early detection of AD, but existing tasks do not enable memory profiling. We developed a novel PAL task enabling the differentiation of memory profiles in 19 people with AD, 17 people with amnestic MCI, and 33 normal elderly controls. Unexpectedly, the AD group demonstrated a retrieval profile for PAL using yes-no recognition, although an encoding profile was evident for forced-choice recognition and for the California Verbal Learning Test--Second Edition (Delis, Kramer, Kaplan, & Ober, 2000). There was considerable heterogeneity within the AD and MCI groups as well as intraindividual discordance for memory profiles. The findings challenge the clinical application of memory profiling in the differential diagnosis of AD, and, by extension, question its potential application in the assessment of MCI.
轻度认知障碍（MCI）与患阿尔茨海默病（AD）的风险增加相关，但高达40%的病例不会发展为AD。检查病例的特定记忆特征可能有助于区分哪些MCI病例会进展为AD：编码特征提示早期AD，而检索特征提示其他病因。配对联想学习（PAL）任务对AD的临床前和早期检测很敏感，但现有任务无法进行记忆特征分析。我们开发了一种新颖的PAL任务，能够区分19名AD患者、17名遗忘型MCI患者和33名正常老年对照的记忆特征。出乎意料的是，AD组在使用是非判断识别时表现出PAL的检索特征，尽管在强制选择识别和加州言语学习测验第二版（Delis、Kramer、Kaplan和Ober，2000）中编码特征很明显。AD组和MCI组内部存在相当大的异质性，并且记忆特征在个体内部也不一致。这些发现挑战了记忆特征分析在AD鉴别诊断中的临床应用，进而质疑其在MCI评估中的潜在应用。
