Leonard Davis School of Gerontology, University of Southern California, USA; Department of Psychology, Ryerson University, Canada.
Department of Psychology, Ryerson University, Canada.
Brain Res. 2018 Oct 15;1697:83-92. doi: 10.1016/j.brainres.2018.06.019. Epub 2018 Jun 18.
The ability to selectively remember important information and forget irrelevant details is fundamental to successful memory. Research has shown that both younger and older adults can intentionally remember and forget information varying in emotional valence; however, whether the neural correlates of these processes change with age is unknown. In this event-related potential (ERP) study, we sought to fill this knowledge gap using the item-directed forgetting (DF) task. Younger and older adults encoded positive, negative, or neutral words that were cued as either to-be-remembered (TBR) or to-be-forgotten (TBF), while brain activity was recorded with electroencephalography (EEG). Behaviorally, both age groups showed DF effects, although the magnitude of DF was reduced in older adults. Moreover, DF was not influenced by the emotional valence of words in either age group. In the brain, age differences emerged across both word- and cue-related ERPs. Whereas the late positive potential (LPP) was greater for negative than positive words in younger adults, older adults showed a reduced LPP for negative versus positive items. In response to memory cues, younger adults' ERPs showed enhanced parietal and frontal positivity following TBR and TBF cues, respectively. In contrast, older adults displayed greater frontal activity while encoding TBR items than younger adults but age invariance in parietal ERPs following TBR cues. Together, these findings suggest that both younger and older adults are able to intentionally forget information that varies in emotional valence but that the neural mechanisms underlying these processes may change with age.
选择性记住重要信息并忘记不相关细节的能力是成功记忆的基础。研究表明,年轻和老年成年人都可以有意地记住和忘记在情绪效价上不同的信息;然而,这些过程的神经相关性是否会随年龄变化尚不清楚。在这项事件相关电位(ERP)研究中,我们试图使用项目定向遗忘(DF)任务来填补这一知识空白。年轻和老年成年人编码正面、负面或中性的单词,这些单词被提示为要记住(TBR)或要忘记(TBF),同时使用脑电图(EEG)记录大脑活动。行为上,两个年龄组都表现出 DF 效应,尽管老年组的 DF 幅度降低。此外,DF 不受单词情绪效价的影响,无论年龄组如何。在大脑中,词和线索相关的 ERP 都出现了年龄差异。在年轻成年人中,负性单词的晚期正电位(LPP)大于正性单词,而老年成年人的负性和正性项目的 LPP 则降低。在记忆线索方面,年轻成年人的 ERP 在 TBR 和 TBF 线索后分别显示出顶叶和额叶正性增强。相比之下,老年成年人在编码 TBR 项目时比年轻成年人显示出更大的额叶活动,但在 TBR 线索后顶叶 ERP 没有年龄差异。总之,这些发现表明,年轻和老年成年人都能够有意地忘记在情绪效价上不同的信息,但这些过程的神经机制可能会随年龄变化。