ABSTRACT

Recent advances in multivariate neuroimaging analyses have made possible the examination of the similarity of the neural patterns of activations measured across participants, but it has not been investigated yet whether such measure is age-sensitive. Here, in the scanner, young and older participants viewed scene pictures associated with labels. At test, participants were presented with the labels and were asked to recollect the associated picture. We used Pattern Similarity Analyses by which we compared patterns of neural activation during the encoding or the remembering of each picture of one participant with the averaged pattern of activation across the remaining participants. Results revealed that across-participants neural similarity was higher in young than in older adults in distributed occipital, temporal and parietal areas during encoding and retrieval. These findings demonstrate that an age-related reduction in specificity of neural activation is also evident when the similarity of neural representations is examined across participants.

摘要

多变量神经影像分析的最新进展使得检查参与者之间测量的激活的神经模式的相似性成为可能，但尚未研究这种测量是否对年龄敏感。在这里，在扫描仪中，年轻和年长的参与者查看与标签相关的场景图片。在测试中，参与者被展示了标签并被要求回忆相关的图片。我们使用了模式相似性分析，通过该分析，我们将一个参与者的每张图片的编码或记忆过程中的神经激活模式与其余参与者的平均激活模式进行了比较。结果显示，年轻人的跨参与者神经相似性在分布式枕骨中高于老年人，编码和检索过程中的颞叶和顶叶区域。这些发现表明，当在参与者之间检查神经表征的相似性时，与年龄相关的神经激活特异性降低也很明显。