The ability to adapt to varying task demands is essential for goal-directed behavior. Cognitive control styles regulate this adaptation, with persistence reflecting high top–down control and flexibility reflecting lower control. Metacontrol facilitates the dynamic adjustment between these states based on current demands. The present study investigated short-term feedback-dependent adaptations in cognitive control style during conflict monitoring. Behavioral results demonstrated that RT feedback promoted a more persistent cognitive control style in subsequent trials, improving performance in incongruent conditions while diminishing facilitative effects in congruent conditions. On the neurophysiological level, theta-band activity primarily reflected these changes during conflict processing. Crucially, intertrial interval analyses revealed a key role of beta-band activity in using RT feedback. Correlations with behavioral congruency effects suggested that decreased beta-band activity reflected a generally more flexible control style, whereas increased beta-band activity was associated with generally greater persistence. By demonstrating that pretrial beta-band modulations reflect cognitive control dispositions, this study provides novel insights into the neural mechanisms underlying metacontrol.