Proactive control without midfrontal control signals? The role of midfrontal oscillations in preparatory conflict adjustments

Successful motor control during behavioral conflicts relies on neural adjustments that can occur reactively (i.e., after conflict occurrence) and proactively (i.e., in preparation prior to conflicts). While midfrontal delta/theta oscillations are known to play a role for reactive control, their relevance for proactive control is unclear. Using EEG, we investigated the role of midfrontal oscillations during conflict preparation in a motor conflict task, where a predictive cue either indicated no or an increased likelihood for an action conflict. During conflict preparation, increased conflict likelihood led to a proactive modulation of neural oscillations related to both motor processing (central beta) and sensory processing (posterior alpha). While midfrontal control oscillations significantly increased during conflict occurrence, increased conflict likelihood did not change midfrontal oscillatory activity during conflict preparation. This dissociation suggests that, while midfrontal oscillations are related to reactive conflict adjustments, proactive neural adjustment can be implemented without midfrontal oscillatory control.