Schoemaker Dorothee, Poirier Judes, Collins D Louis, Gauthier Serge, Pruessner Jens C
McGill Centre for Studies in Aging, McGill University, Verdun, Quebec, Canada.
Douglas Mental Health University Institute Research Centre, Verdun, Quebec, Canada.
Alzheimers Dement (Amst). 2017 Jun 15;9:21-24. doi: 10.1016/j.dadm.2017.05.008. eCollection 2017.
The apolipoprotein E ε4 ( ε4) allele is a well-documented risk factor for Alzheimer's disease (AD). Accordingly, aging individuals carrying one or more ε4 alleles are at considerably greater risk of developing AD over time. In an effort to characterize early cognitive manifestations of AD, we previously outlined selective deficits in familiarity-based recognition in otherwise asymptomatic carriers of the ε4 allele (Schoemaker et al., 2016). In this follow-up report, we aimed to explore the neural correlates of this selective cognitive impairment.
For this purpose, within the same population and using high-resolution structural neuroimaging, we explored relationships between volumes of the hippocampus, entorhinal, and perirhinal cortices and performance in recollection and familiarity.
Overall, our results revealed significant positive relationships between familiarity performance and volumes of the perirhinal and entorhinal cortices in aging individuals with ε4. In ε4 carriers, a positive correlation between recollection performance and hippocampal volume was also found. In contrast, no correlation reached statistical significance in the group of noncarriers.
These findings suggest that familiarity performance might be a useful marker of the integrity of the rhinal cortex, especially in populations at risk of AD.
载脂蛋白E ε4（ε4）等位基因是阿尔茨海默病（AD）一个有充分文献记载的风险因素。因此，随着时间推移，携带一个或多个ε4等位基因的老年人患AD的风险要高得多。为了描述AD早期的认知表现，我们之前概述了在ε4等位基因无症状携带者中基于熟悉度的识别方面的选择性缺陷（Schoemaker等人，2016年）。在这份后续报告中，我们旨在探索这种选择性认知障碍的神经关联。
为此，在同一人群中并使用高分辨率结构神经成像，我们探索了海马体、内嗅皮质和鼻周皮质的体积与回忆和熟悉度表现之间的关系。
总体而言，我们的结果显示，在携带ε4的老年人中，熟悉度表现与鼻周皮质和内嗅皮质的体积之间存在显著正相关。在ε4携带者中，还发现回忆表现与海马体体积之间存在正相关。相比之下，在非携带者组中没有相关性达到统计学显著水平。
这些发现表明，熟悉度表现可能是鼻周皮质完整性的一个有用指标，尤其是在有患AD风险的人群中。
