FIGURE 1.

(a) Experimental design; (b) Task procedure: two target displays were presented on each trial and, in different blocks, participants were instructed to find the position of the single‐odd element (segregation trials) or to find the position of the single empty location (integration trials); no time constraints were imposed to subjects; (c) tACS/EEG montage employed and the estimated electric field distribution on the cortical surface; (d) Visual representation of the main hypothesis of the current study. According to the theoretical framework of rhythmic perception, higher frequencies imply shorter integration windows and should be associated with better segregation performance, but reduced integration performance. In contrast, lower frequency should facilitate integration, because stimuli are more likely to fall within the same oscillatory alpha cycle/integration window