Alpha Oscillations Encode Bayesian Belief Updating Underlying Attentional Allocation in Dynamic Environments

Abstract

AbstractIn a dynamic environment, expectations of the future constantly change based on updated evidence and affect the dynamic allocation of attentional resources.To further investigate the neural mechanisms underlying efficient allocation of attention, we employed a modified Central Cue Posner paradigm in which the probability of cues being valid (that is, accurately indicated the upcoming target location) was manipulated. The proportion of attentional resources allocated to the cued location (α), which was sensitive to precision of predictions on previous trials, was estimated using a hierarchical Bayesian model and was included as a regressor in the analyses of electrophysiological (EEG) data. Our results revealed that before the target appeared, the attentional modulation of alpha oscillations (8∼13Hz) for high-certainty cues (88% valid) were significantly predicted by the attentional resources measure (α). This relationship was not observed under low-certainty conditions (69% and 50% valid cues). After the target appeared, the attentional resources measure (α) correlated with alpha band oscillations only in the valid cue condition and not in the invalid condition. These results provide new insights on how trial-by-trial Bayesian belief updating relates to alpha band encoding environmentally-sensitive allocation of visual spatial attention.