The Yin and the Yang of Prediction: An fMRI Study of Semantic Predictive Processing.
The Yin and the Yang of Prediction: An fMRI Study of Semantic Predictive Processing.
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DOI：
10.1371/journal.pone.0148637
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发表时间：
2016
期刊：
影响因子：
3.7
通讯作者：
Kuperberg GR
中科院分区：
文献类型：
--
作者：
Weber K;Lau EF;Stillerman B;Kuperberg GR
概率预测在语言理解中起着至关重要的作用。当预测实现时，由此产生的促进允许对模糊的、快速展开的输入进行快速、有效的处理；当预测没有实现时，由此产生的误差信号使我们能够适应该输入中更广泛的统计变化。我们使用功能性磁共振成像来检查参与语义预测加工和适应的神经解剖学网络。我们使用了关联比例语义启动范式，在保持局部语义上下文不变的情况下，我们操纵了预测的概率。在较高（相对较低）预测效度的条件下，我们重复了先前观察到的左前上/中颞叶皮层对语义可预测单词的活动减少，反映了与先前语义预测一致的目标加工的便利。此外，在预测效度较高（相对较低）的条件下，我们观察到左侧额下回和左侧颞上回/中回后部的语义相关性的影响存在显著差异。我们认为这两个区域共同介导了未完成的语义预测和与这些预测不一致的不相关目标的词汇语义加工的抑制。此外，在预测效度较高（相对较低）的情况下，功能连通性分析显示，左侧额下回和左侧后颞上回/中回之间以及与左侧前扣带皮层之间的联系更为紧密。而左前扣带皮层则与上外侧额叶皮层和皮层下区域的连接更为紧密，这是一个调节快速学习和适应的网络，它可能在响应更广泛环境背景的统计结构而转向更具预测性的处理模式方面发挥了作用。总之，这些发现突出了网络之间的密切联系，调解语义预测，执行功能和学习，为我们的大脑如何能够灵活地适应我们的环境提供了新的见解。
Probabilistic prediction plays a crucial role in language comprehension. When predictions are fulfilled, the resulting facilitation allows for fast, efficient processing of ambiguous, rapidly-unfolding input; when predictions are not fulfilled, the resulting error signal allows us to adapt to broader statistical changes in this input. We used functional Magnetic Resonance Imaging to examine the neuroanatomical networks engaged in semantic predictive processing and adaptation. We used a relatedness proportion semantic priming paradigm, in which we manipulated the probability of predictions while holding local semantic context constant. Under conditions of higher (versus lower) predictive validity, we replicate previous observations of reduced activity to semantically predictable words in the left anterior superior/middle temporal cortex, reflecting facilitated processing of targets that are consistent with prior semantic predictions. In addition, under conditions of higher (versus lower) predictive validity we observed significant differences in the effects of semantic relatedness within the left inferior frontal gyrus and the posterior portion of the left superior/middle temporal gyrus. We suggest that together these two regions mediated the suppression of unfulfilled semantic predictions and lexico-semantic processing of unrelated targets that were inconsistent with these predictions. Moreover, under conditions of higher (versus lower) predictive validity, a functional connectivity analysis showed that the left inferior frontal and left posterior superior/middle temporal gyrus were more tightly interconnected with one another, as well as with the left anterior cingulate cortex. The left anterior cingulate cortex was, in turn, more tightly connected to superior lateral frontal cortices and subcortical regions—a network that mediates rapid learning and adaptation and that may have played a role in switching to a more predictive mode of processing in response to the statistical structure of the wider environmental context. Together, these findings highlight close links between the networks mediating semantic prediction, executive function and learning, giving new insights into how our brains are able to flexibly adapt to our environment.