Figure 2.

Time course of grand-averaged α-band oscillatory activity as a function of cueing condition shown (A) for all recorded electrodes, and (B) for selected posterior electrode sites (pooled per hemisphere) that showed maximal modulation of α-band activity in the cue–target interval (left and right panels). The middle panel in B represents the time course of the corresponding α-lateralization index over the posterior recording sites. Sustained changes in α-band oscillations are seen in the cue–target interval (A, B, left and right panels), which depended on the cued direction of attention and the side of recording. These attention-related changes were driven by varying degrees of α decreases, being maximal over the hemisphere contralateral to the attended position and significantly different from baseline (precue period). The corresponding α-lateralization indices (B, middle) revealed an overall (negative) bias in the distribution of attention-related α activity (α_right < α_left), suggestive of an overall asymmetric attention bias (in favor of the left hemifield).