Recent models of human behavior suggest a hierarchical organization of cognitive control processes. These models assume that different sub-goals of cognitive control processes are nested in each other, such that higher-level sub-goals can only be accomplished when lower-level sub-goals have been realized. While the neuroanatomical localization of this organizational principle has already been successfully tested, the exact temporal nature remains to be explored. The present study applied event-related potentials (ERPs) and investigated neural oscillations during performance of three different nested cognitive control tasks. Results demonstrated a parametric modulation of the P300 component as well as beta-band (13–25 Hz) oscillations as a function of different levels of cognitive control. Moreover, conditions requiring flexible updating of information exhibited similar alpha-band (8–13 Hz) oscillations, which differed from the condition without flexible updating (low-level). These results suggest dissociable mechanisms of flexible information updating and complexity of cognitive control processes indexed by different oscillatory effects.