Georgia Institute of Technology, School of Psychology, 654 Cherry Street NW, Atlanta, GA, 30332-0170, United States.
Georgia Institute of Technology, School of Psychology, 654 Cherry Street NW, Atlanta, GA, 30332-0170, United States.
Neuroimage. 2018 Nov 1;181:95-107. doi: 10.1016/j.neuroimage.2018.06.085. Epub 2018 Jul 2.
Emerging evidence has suggested that the tendency for older adults to bind too much contextual information during encoding (i.e., hyper-binding) may contribute to poorer memory for relevant contextual information during retrieval. While these findings are consistent with theories of age-related declines in selective attention and inhibitory control, the degree to which older adults are able to selectively attend to relevant contextual information during encoding is unknown. To better understand the neural dynamics associated with selective attention during encoding, the current study applied multivariate pattern analyses (MVPA) to oscillatory EEG in order to track moment-to-moment shifts of attention between relevant and irrelevant contextual information during encoding. Young and older adults studied pictures of objects in the presence of two contextual features: a color and a scene, and their attention was directed to the object's relationship with one of those contexts (i.e., target context). Results showed that patterns of oscillatory power successfully predicted whether selective attention was directed to a scene or color, across age groups. Individual differences in overall classification performance were associated with individual differences in target context memory accuracy during retrieval. However, changes in classification performance within a trial, suggestive of fluctuations in selective attention, predicted individual differences in hyper-binding. To the best of our knowledge, this is the first study to use MPVA techniques to decode attention during episodic encoding and the impact of attentional shifts toward distracting information on age-related context memory impairments and hyper-binding. These results are consistent with the as-of-yet unsubstantiated theory that age-related declines in context memory may be attributable to poorer selective attention and/or greater inhibitory deficits in older adults.
新出现的证据表明，老年人在编码过程中过度结合上下文信息（即过度绑定）的倾向可能导致检索过程中对相关上下文信息的记忆较差。虽然这些发现与选择性注意和抑制控制随年龄增长而下降的理论一致，但老年人在编码过程中选择性地注意相关上下文信息的程度尚不清楚。为了更好地理解编码过程中选择性注意的神经动力学，本研究应用多变量模式分析（MVPA）对振荡 EEG 进行分析，以跟踪编码过程中注意力在相关和不相关上下文信息之间的瞬间转移。年轻和老年成年人在存在两种上下文特征的情况下研究物体的图片：颜色和场景，并将注意力引导到物体与这些上下文之一的关系上（即目标上下文）。结果表明，振荡功率模式成功预测了选择性注意力是指向场景还是颜色，跨越年龄组。整体分类性能的个体差异与检索期间目标上下文记忆准确性的个体差异相关。然而，在一次试验内的分类性能变化，表明选择性注意力的波动，预测了过度绑定的个体差异。据我们所知，这是第一项使用 MPVA 技术解码情节性编码期间注意力的研究，以及注意力向分散信息转移对与年龄相关的上下文记忆损伤和过度绑定的影响。这些结果与尚未证实的理论一致，即与年龄相关的上下文记忆下降可能归因于老年人选择性注意力较差和/或抑制缺陷更大。
