Brain oscillatory 4-35Â Hz EEG responses during an n-back task with complex visual stimuli

► Brain oscillatory EEG responses were assessed during a visual n-back task. ► The stimuli used were visually complex and ecologically meaningful. ► Stimulus presentation elicited 4-8 Hz power increases and 8-25 Hz power decreases. ► 4-8 Hz power increases were more prominent during presentation of targets in 0-back. ► The duration of 8-25 Hz power decreases increased as a function of memory load.