Theta Coupling in the Human EEG During the Control of Bottom-up and Top-down Attention

Abstract

We investigated the difference of theta coupling value between top-down and bottom-up visual attention using electrophysiological measures in humans. Triangles, each with a different color and orientation were the stimuli in our study. A sample triangle, served as the target, was presented to subjects. An array with the target and three additional distractor stimuli was subsequently presented. For pop-out, the distractor differed from the target both the color and orientation, while for search, the distractor differed from the target only the orientation. We calculated the theta coupling value from 0 to 600 ms after the stimuli onset. Both behavioral and theta coupling value showed that the search task have poor performance and more connected in parietal network that demand more cognitive effort. Also, the result showed that the posterior brain regions playing an important role in top-down control.