Figure 5.

Local and large-scale synchrony reflects the attentional selection of sensory evidence. (A) Schematic illustration of the stimulus display during the spatially cued motion-discrimination task. (B) Attentional modulation of local oscillatory population activity in four regions of interest (marked on the inflated hemispheres to the left). Attentional modulations are displayed as predictive indices that quantify the probability with which an ideal observer can predict the direction of attention (left vs. right) from lateralization of neural responses between the left and right hemispheres on a single trial level. Predictive indices larger or smaller than chance level (0.5) correspond to an attentional enhancement or suppression of activity in the hemisphere contralateral to the attended hemifield, respectively. (C) Attentional modulation of frequency-specific long-range synchronization. Panels in the upper row display between which cortical regions spatial attention significantly enhanced synchronization in the hemisphere contralateral as compared to ipsilateral to the attended visual hemifield. Panels in the lower row depict corresponding attentional reductions of synchronization. Colors indicate the frequency bands of significantly modulated long-range synchrony. All attentional modulations are displayed separately for the delay interval (750–0 ms before stimulus onset) and stimulus interval (100–500 ms after stimulus onset). (*p < 0.05, **p < 0.01, ***p < 0.001 corrected; FEF, frontal eye field; PIPS, posterior intraparietal sulcus; MT, middle temporal area; V1/V2, pericalcarine cortex). Reprinted and modified with permission from Siegel et al. (2008).