Abstract
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.
Highlights
It has been proposed that the brain specializes in predicting future states of the environment
A number of event-related potentials (ERP) components and oscillations have been linked to prediction in non-accumulative experimental contexts, but it is unclear how they relate to evidence accumulation for prediction build-up
Regarding P2, recent literature suggests that a frontally distributed component of that family peaking around 350 ms post-stimulus, the prefrontal P2 or pP2, is associated with evidence accumulation for decision-making[10,11,12]. This component has been suggested to represent the final stage of the decision-making process, once enough action-related information is accumulated, before the emission of a response[12,13], and to be itself associated with the evidence accumulation process[10]
Summary
It has been proposed that the brain specializes in predicting future states of the environment. Most previous research has focused on brain activity related to either the fulfilment or the violation of predictions made on the basis of strong contextual regularities, usually the continuous repetition of a stimulus[5,6], the presentation of predictable pairs of stimuli where the first predicts the second[7] or a fixed and predetermined sequence of stimuli[8,9] All these experiments have in common that expectations involve a binary prediction, i.e., an event is expected to occur or not, and subjects know, in case it occurs, what it will exactly consist of, so they can hypothetically generate a strong and precise template and compare the upcoming event with it. Evidence suggests a role of theta oscillations in the implementation of a general, multipurpose information accumulation mechanism in the brain
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
