Dave S, Brothers T A, Swaab T Y
Department of Psychology and Center for Mind and Brain, University of California, Davis, CA, United States; Department of Medical Social Sciences, Feinberg School of Medicine, Northwestern University, United States.
Department of Psychology and Center for Mind and Brain, University of California, Davis, CA, United States; Department of Psychology, Tufts University, United States.
Brain Res. 2018 Jul 15;1691:34-43. doi: 10.1016/j.brainres.2018.04.007. Epub 2018 Apr 18.
Prediction of upcoming words during reading has been suggested to enhance the efficiency of discourse processing. Emerging models have postulated that predictive mechanisms require synchronous firing of neural networks, but to date, this relationship has been investigated primarily through oscillatory activity in narrow frequency bands. A recently-developed measure proposed to reflect broadband neural activity - and thereby synchronous neuronal firing - is 1/f neural noise extracted from EEG spectral power. Previous research has indicated that this measure of 1/f neural noise changes across the lifespan, and these neural changes predict age-related behavioral impairments in visual working memory. Using a cross-sectional sample of young and older adults, we examined age-related changes in 1/f neural noise and whether this measure predicted ERP correlates of successful lexical prediction during discourse comprehension. 1/f neural noise across two different language tasks revealed high within-subject correlations, indicating that this measure can provide a reliable index of individualized patterns of neural activation. In addition to age, 1/f noise was a significant predictor of N400 effects of successful lexical prediction; however, noise did not mediate age-related declines in other ERP effects. We discuss broader implications of these findings for theories of predictive processing, as well as potential applications of 1/f noise across research populations.
阅读过程中对即将出现的单词进行预测被认为可以提高语篇处理的效率。新兴模型推测，预测机制需要神经网络的同步放电，但迄今为止，这种关系主要是通过窄频带中的振荡活动来研究的。最近开发的一种用于反映宽带神经活动（从而反映神经元同步放电）的测量方法是从脑电图频谱功率中提取的1/f神经噪声。先前的研究表明，这种1/f神经噪声的测量值在整个生命周期中会发生变化，并且这些神经变化预示着视觉工作记忆中与年龄相关的行为损伤。我们使用年轻人和老年人的横断面样本，研究了1/f神经噪声与年龄相关的变化，以及该测量值是否能预测语篇理解过程中成功词汇预测的事件相关电位（ERP）相关性。在两项不同语言任务中的1/f神经噪声显示出较高的受试者内相关性，表明该测量值可以为神经激活的个体模式提供可靠指标。除了年龄，1/f噪声还是成功词汇预测的N400效应的重要预测指标；然而，噪声并未介导其他ERP效应中与年龄相关的下降。我们讨论了这些发现对预测处理理论的更广泛影响，以及1/f噪声在不同研究人群中的潜在应用。
