Fig. 1.

Task design showing analysis periods and behavioral results. (A) Subjects participated in a Posner cued attention task, with the most probable target location indicated by an arrowhead presented at fixation prior to target onset. Phase amplitude coupling (PAC) was analyzed during the cue period. Functional classifications were based on high-gamma amplitude during the target period. Subjects responded to “L” and “T” targets with left and right mouse clicks. (B) Reaction times were greater for invalid than valid trials and (C) for variable than fixed delays.