University of Valencia, Valencia, Spain.
Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2012 Sep;19(5):608-19. doi: 10.1080/13825585.2011.640657. Epub 2012 Jan 17.
There is no agreement on the pattern of recognition memory deficits characteristic of patients diagnosed with mild cognitive impairment (MCI). Whereas lower performance in recollection is the hallmark of MCI, there is a strong controversy about possible deficits in familiarity estimates when using recognition memory tasks. The aim of this research is to shed light on the pattern of responding in recollection and familiarity in MCI. Five groups of participants were tested. The main participant samples were those formed by two MCI groups differing in age and an Alzheimer's disease group (AD), which were compared with two control groups. Whereas one of the control groups served to assess the performance of the MCI and AD people, the other one, composed of young healthy participants, served the purpose of evaluating the adequacy of the experimental tasks used in the evaluation of the different components of recognition memory. We used an associative recognition task as a direct index of recollection and a choice task on a pair of stimuli, one of which was perceptually similar to those studied in the associative recognition phase, as an index of familiarity. Our results indicate that recollection decreases with age and neurological status, and familiarity remains stable in the elderly control sample but it is deficient in MCI. This research shows that a unique encoding situation generated deficits in recollective and familiarity mechanisms in mild cognitive impaired individuals, providing evidence for the existence of deficits in both retrieval processes in recognition memory in a MCI stage.
对于被诊断为轻度认知障碍（MCI）的患者的识别记忆缺陷模式，目前尚无共识。虽然回忆表现下降是 MCI 的标志，但在使用识别记忆任务时，熟悉度估计可能存在缺陷存在很大争议。本研究旨在阐明 MCI 中回忆和熟悉度的反应模式。共测试了五组参与者。主要参与者样本包括两个年龄不同的 MCI 组和一个阿尔茨海默病组（AD），并与两个对照组进行了比较。其中一个对照组用于评估 MCI 和 AD 人群的表现，另一个对照组由年轻健康参与者组成，用于评估用于评估识别记忆不同成分的实验任务的充分性。我们使用联想识别任务作为回忆的直接指标，以及在一对刺激上进行的选择任务，其中一个刺激在感知上与联想识别阶段中研究的刺激相似，作为熟悉度的指标。我们的结果表明，回忆随着年龄和神经状态的变化而下降，而在老年对照组中，熟悉度保持稳定，但在 MCI 中则不足。这项研究表明，独特的编码情况导致轻度认知障碍个体的回忆和熟悉机制出现缺陷，为 MCI 阶段识别记忆中的两种检索过程都存在缺陷提供了证据。
