Strunk Jonathan, James Taylor, Arndt Jason, Duarte Audrey
School of Psychology, Georgia Institute of Technology, Atlanta, GA, USA.
School of Psychology, Georgia Institute of Technology, Atlanta, GA, USA.
Cortex. 2017 Jun;91:40-55. doi: 10.1016/j.cortex.2017.01.020. Epub 2017 Feb 3.
Recent evidence suggests that directing attention toward single item-context associations during encoding improves young and older adults' context memory performance and reduces demands on executive functions during retrieval. In everyday situations, there are many event features competing for our attention, and our ability to successfully recover those details may depend on our ability to ignore others. Failures of selective attention may contribute to older adults' context memory impairments. In the current electroencephalogram (EEG) study, we assessed the effects of age on processes supporting successful context memory retrieval of selectively attended features as indexed by neural oscillations. During encoding, young and older adults were directed to attend to a picture of an object and its relationship to one of two concurrently presented contextual details: a color or scene. At retrieval, we tested their memory for the object, its attended and unattended context features, and their confidence for both the attended and unattended features. Both groups showed greater memory for attended than unattended contextual features. However, older adults showed evidence of hyper-binding between attended and unattended context features while the young adults did not. EEG results in the theta band suggest that young and older adults recollect similar amounts of information but brain-behavior correlations suggest that this information was supportive of contextual memory performance, particularly for young adults. By contrast, sustained beta desynchronization, indicative of sensory reactivation and episodic reconstruction, was correlated with contextual memory performance for older adults only. We conclude that older adults' inhibition deficits during encoding reduced the selectivity of their contextual memories, which led to reliance on executive functions like episodic reconstruction to support successful memory retrieval.
最近的证据表明，在编码过程中将注意力导向单个项目与情境的关联，可改善年轻人和老年人的情境记忆表现，并减少检索过程中对执行功能的需求。在日常情况下，有许多事件特征争夺我们的注意力，而我们成功恢复这些细节的能力可能取决于我们忽略其他特征的能力。选择性注意的失败可能导致老年人的情境记忆受损。在当前的脑电图（EEG）研究中，我们评估了年龄对支持成功情境记忆检索的过程的影响，这些过程由神经振荡来索引。在编码过程中，引导年轻人和老年人关注一个物体的图片及其与同时呈现的两个情境细节之一的关系：颜色或场景。在检索时，我们测试了他们对物体、其被关注和未被关注的情境特征的记忆，以及他们对被关注和未被关注特征的信心。两组在对被关注的情境特征的记忆上都比对未被关注的情境特征的记忆更好。然而，老年人在被关注和未被关注的情境特征之间表现出过度绑定的证据，而年轻人则没有。θ波段的脑电图结果表明，年轻人和老年人回忆的信息量相似，但脑与行为的相关性表明，这些信息对情境记忆表现有支持作用，特别是对年轻人。相比之下，持续的β去同步化，这表明感觉再激活和情景重建，仅与老年人的情境记忆表现相关。我们得出结论，老年人在编码过程中的抑制缺陷降低了他们情境记忆的选择性，这导致他们依赖情景重建等执行功能来支持成功的记忆检索。
