Multimodal approaches towards a better understanding of feelings of familiarity

熟悉是一种基本的记忆过程，它提醒我们以前经历过一些事情。研究人员使用了三种常用的方法来测量熟悉度。这项研究报告说，与年轻人相比，健康老年人的熟悉度不足很小，有时甚至很大。遗忘型轻度认知障碍（aMCI）在熟悉性研究中特别令人感兴趣，因为最早的病理发生在嗅周皮层（即，Braak和Braak的“transentorhinal”皮质）和内嗅皮质，这两个区域显示aMCI中的细胞损失和皮质变薄。大多数神经影像学研究发现，嗅周激活与熟悉性相关，对局灶性病变患者的研究发现，熟悉性缺陷损害了嗅周皮层。因此，与健康的老年人相比，假设aMCI中的熟悉度受损是合乎逻辑的，但证据是均匀混合的：当条件支持高水平的回忆时，aMCI中的熟悉度是多余的，但当条件支持低水平的回忆时，aMCI中的熟悉度受损，与健康的同龄人相比。我认为，较高的贡献，回忆掩盖熟悉赤字在aMCI，并可能在健康老龄化，我们需要利用新的方法来衡量熟悉的无回忆的情况下。

Familiarity is a fundamental memory process that alerts us that we have experienced something before. Researchers have used one of three prevailing methods used to measure familiarity. This research has reported small and sometimes significant familiarity deficits in healthy older adults, compared to younger adults. Amnestic mild cognitive impairment (aMCI) is of particular interest in the study of familiarity because the earliest pathology occurs in the perirhinal cortex (i.e., Braak & Braak’s ‘transentorhinal’ cortex) and entorhinal cortex, two regions that show cell loss and cortical thinning in aMCI. Most neuroimaging research finds perirhinal activation associated with familiarity, and research with patients with focal lesions finds familiarity deficits damage to the perirhinal cortex. It would thus be logical to hypothesize that familiarity is impaired in aMCI, compared to healthy older adults, but the evidence is evenly mixed: when conditions support high levels of recollection, familiarity is spared in aMCI, but when conditions support low levels of recollection, familiarity is impaired in aMCI, compared to their healthy counterparts. I suggest that higher contributions of recollection overshadow familiarity deficits in aMCI, and potentially in healthy aging, and that we need to utilize new methods to measure familiarity in recollection-free contexts.