Figure 4.
Quantitative analysis across all subjects reveals no hemispheric lateralization of local/global attention. For each vertex in each (tessellated) cortical surface, fMRI activity was sampled preferentially from the middle and lower layers of the gray matter (e.g., refs. 16 and 34–36). This activity was added together to give a total number of activated vertices (y axis) for each of three different significance threshold levels (x axis). At all three levels, more cortical vertices were activated during global attention than during local attention, consistent with the greater cortical representation of the global attention target. However, there was no significant lateralization of local/global attention. The brackets above each bar represent one standard deviation.