Randoph Helfrich and Robert Knight review evidence that the infrastructure of cognitive control is rhythmic.  The general idea is that the prefrontal cortex controls large-scale oscillatory dynamics in the cortex and subcortex.  But there is much more.  Do yourself a favor: Read it.

Helfrich, R. F., & Knight, R. T. (2016). Oscillatory Dynamics of Prefrontal Cognitive Control. Trends in Cognitive Sciences.