Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France.
Centre National de la Recherche Scientifique, Laboratoire Psychologie de la Perception, Unité Mixte de Recherche 8242, 75006, Paris, France.
Sci Rep. 2018 Jan 11;8(1):494. doi: 10.1038/s41598-017-18802-z.
It has been proposed that the brain specializes in predicting future states of the environment. These predictions are probabilistic, and must be continuously updated on the basis of their mismatch with actual evidence. Although electrophysiological data disclose neural activity patterns in relation to predictive processes, little is known about how this activity supports prediction build-up through evidence accumulation. Here we addressed this gap. Participants were required to make moment-by-moment predictions about stimuli presented in sequences in which gathering evidence from previous items as they were presented was either possible or not. Two event-related potentials (ERP), a frontocentral P2 and a central P3, were sensitive to information accumulation throughout the sequence. Time-frequency (TF) analyses revealed that prediction build-up process also modulated centrally distributed theta activity, and that alpha power was suppressed in anticipation to fully predictable stimuli. Results are in agreement with the notion of predictions as probability distributions and highlight the ability of observers to extract those probabilities in a changing environment and to adjust their predictions consequently.
有人提出，大脑专门用于预测环境的未来状态。这些预测是概率性的，必须根据它们与实际证据的不符之处进行持续更新。尽管电生理数据揭示了与预测过程相关的神经活动模式，但对于这种活动如何通过证据积累来支持预测建立，我们知之甚少。在这里，我们解决了这个差距。要求参与者对序列中呈现的刺激进行即时预测，在这些序列中，从呈现的前一个项目中收集证据是可能的或不可能的。两个事件相关电位（ERP），额中央 P2 和中央 P3，对整个序列中的信息积累敏感。时频（TF）分析显示，预测建立过程也调制了中央分布的 theta 活动，并且在完全可预测的刺激之前，alpha 功率被抑制。结果与预测作为概率分布的概念一致，并强调了观察者在不断变化的环境中提取这些概率并相应调整预测的能力。
