In this view, oscillations provide the scaffolding for information processing: selectively sampling sensory inputs, disengaging task-irrelevant areas, and temporarily connecting relevant nodes such that efficient and effective exchange of information can take place. Considering the sheer number of brain cells and their anatomical connections, this is not a trivial task. The oscillatory building blocks we focus on, and their proposed mechanistic roles, are: (A) slow oscillations in the delta/theta bands (1–7 Hz), providing selective sampling of sensory input, (B) the alpha rhythm (8–14 Hz), involved in active functional inhibition, and (C) beta oscillations (15–30 Hz), forming transient, flexible neural ensembles. Combined, these building blocks allow for the filtering of incoming information, and successfully routing this information—encoded in spike activity patterns—through the brain. We use a combination of MEG, ECoG, LFP & spike recordings, as well as psychophysics and computational modelling, to test these ideas at all critical levels.