Callahan Brandy L, Laforce Robert, Dugas Michel, Hudon Carol
École de psychologie,Université Laval,Québec,Canada.
Clinique interdisciplinaire de mémoire du CHU de Québec,Québec,Canada.
Int Psychogeriatr. 2017 Apr;29(4):673-685. doi: 10.1017/S1041610216002179. Epub 2016 Dec 15.
Studies of amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) have examined the similarities and differences between these syndromes, but few have investigated how the cognitive profile of comorbid aMCI and subclinical depressive symptoms (aMCI/D+) may compare to that of aMCI or LLD. Memory biases for certain types of emotional information may distinguish these groups.
A total of 35 aMCI, 23 aMCI/D+, 13 LLD, and 17 elderly controls (CONT) rated the valence (positive, negative, or neutral) of 30 pictures from the International Affective Picture System. Mean percent positive, negative, and neutral images recalled was compared within groups immediately and 30 minutes later.
Overall memory performance was comparable in aMCI and aMCI/D+, and both recalled fewer items than CONT and LLD. Group differences emerged when valence ratings were considered: at immediate and delayed recall, positive and negative pictures were generally better-remembered than neutral pictures by CONT, aMCI, and LLD, but valence was not associated with recall in aMCI/D+. Follow-up analyses suggested that the perceived intensity of stimuli may explain the emotional enhancement effect in CONT, aMCI, and LLD.
Results support previous research suggesting that the neuropsychological profile of aMCI/D+ is different from that of aMCI and LLD. Although depressed and non-depressed individuals with aMCI recall comparable quantities of information, the quality of the recalled information differs significantly. On theoretical grounds, this suggests the existence of distinct neurobiological or neurofunctional manifestations in both groups. Practically, these differences may guide the development of personalized emotion-focused encoding strategies in cognitive training programs.
有关遗忘型轻度认知障碍（aMCI）和老年期抑郁症（LLD）的研究已对这些综合征之间的异同进行了考察，但很少有研究探究共病aMCI与亚临床抑郁症状（aMCI/D+）的认知特征与aMCI或LLD的认知特征相比会有怎样的不同。对某些类型情绪信息的记忆偏差可能会区分这些组别。
共有35名aMCI患者、23名aMCI/D+患者、13名LLD患者和17名老年对照者（CONT）对来自国际情感图片系统的30张图片的效价（积极、消极或中性）进行了评分。对各组在即刻及30分钟后回忆起的积极、消极和中性图片的平均百分比进行了比较。
aMCI组和aMCI/D+组的总体记忆表现相当，且两组回忆起的项目均少于CONT组和LLD组患者。当考虑效价评分时，出现了组间差异：在即刻和延迟回忆时，CONT组、aMCI组和LLD组患者对积极和消极图片的记忆通常比对中性图片更好，但效价与aMCI/D+组的回忆无关。后续分析表明，刺激的感知强度可能解释了CONT组、aMCI组和LLD组中的情绪增强效应。
研究结果支持了先前的研究，表明aMCI/D+的神经心理学特征不同于aMCI和LLD。虽然患有aMCI的抑郁和非抑郁个体回忆起的信息量相当，但所回忆信息的质量存在显著差异。从理论上讲，这表明两组中存在不同的神经生物学或神经功能表现。实际上，这些差异可能会为认知训练项目中个性化的以情绪为重点的编码策略的开发提供指导。
