Interplay of action-based prediction and top-down attention: EEG evidence for joint modulation of late perceptual processing

Voluntary action shapes our perception through sensory predictions of its consequences. These predictions are thought to inhibit perceptual processing of predicted outcomes, leading to sensory attenuation. However, some studies have reported findings that contrast with this effect, suggesting that the influence of predictions may reflect, or interact with, attentional processes. Here, we investigated the interplay of action-based prediction and top-down attention on early and late perceptual processing, where prediction and attention refer to the likelihood of a sensory event and its behavioral relevance, respectively. Electroencephalography (EEG) was recorded while participants viewed two sequential gratings. The orientation of the first was either predicted and self-generated or unpredicted and externally generated. Participants judged the tilt direction of the second grating relative to the first but responded only when the grating appeared in a task-relevant color. EEG analyses revealed no modulation of early visual potentials (N1a), but modulations in later processing stages (P3b). Specifically, the P3b exhibited reduced amplitude for predicted and self-generated stimuli compared to unpredicted and externally generated ones, but only when they were task-relevant. Multivariate pattern analysis further showed that the significant temporal cluster supporting decoding of the first gratings orientation was largest for relevant, predicted and self-generated stimuli. Our results suggest an optimization process whereby action-based prediction, when aligned with task goals, reduces the amount of evidence needed and increases its accumulation speed, while preserving sensory representations as accurate as in the absence of prediction/self-generation. HighlightsO_LIFeature-based attention and prediction were orthogonally manipulated in an agency context. C_LIO_LINo early sensory modulation by attention or action-based prediction was observed. C_LIO_LIReduction of both P3b amplitude and latency emerged for predicted/self-generated and task-relevant stimuli. C_LIO_LIMultivariate analysis and behavior results support an interpretation whereby relevant action-based predictions optimize evidence accumulation process. C_LI