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The present study examined electroencephalogram profiles on a novel stimulus-response compatibility ( SRC) task in order to elucidate the distinct brain mechanisms of stimulus-stimulus ( S- S) and stimulus-response ( S- R) conflict processing. The results showed that the SRC effects on reaction times ( RTs) and N2 amplitudes were additive when both S- S and S- R conflicts existed. We also observed that, for both RTs and N2 amplitudes, the conflict adaptation effects-the reduced SRC effect following an incongruent trial versus a congruent trial-were present only when two consecutive trials involved the same type of conflict. Time-frequency analysis revealed that both S- S and S- R conflicts modulated power in the theta band, whereas S- S conflict additionally modulated power in the alpha and beta bands. In summary, our findings provide insight into the domain-specific conflict processing and the modular organization of cognitive control. [ABSTRACT FROM AUTHOR]

Feedback‐based learning initiated by dopamine (DA) cell firing is crucial for adaptive behavior. The nature and context of feedback can vary, however, affecting how feedback is processed. For example, the feedback‐related negativity (FRN) in the ERP in humans, which has been linked to the DA system, is reduced for delayed feedback and for observational compared to active learning. Recent research suggested that oscillations in the theta and beta band over the medio‐frontal cortex reflect distinct feedback processing mechanisms. In this study, we hypothesized that the power in both frequency bands is affected by feedback delay and agency. We thus investigated effects of feedback delay (1 s vs. 7 s) on induced theta and beta band power and the FRN in a probabilistic feedback learning task in two participant groups, one learning actively and one by observation. For theta and beta, a larger power difference between negative and positive feedback for immediate than delayed feedback was found, driven by positive feedback for beta and by negative feedback for theta, while no differential modulation by agency was seen for theta or beta power following positive and negative feedback. These results indicate that feedback‐locked beta and theta both reflect neural processes that are specific for the integration of feedback and recently preceding events, possibly linked to cognitive control and memory. With respect to the FRN amplitude, we could replicate previous findings of both delay and agency modulations, suggesting that the neural processes underlying feedback‐locked ERPs and theta and beta power modulations differ. To our knowledge, the present study is the first to investigate beta and theta oscillations for feedback that is temporally delayed and/or referring to another person's action. The results suggest valence‐specific neuronal networks reflected by distinct oscillatory activity that are similarly affected by the timing of the feedback. Thereby, the data indicate that both frequency bands reflect neural processes that are specific for the integration of feedback and recently preceding events. Furthermore, the current data show that these networks seem to differ from mechanisms that are reflected by ERPs in the feedback‐related negativity (FRN) time‐window. [ABSTRACT FROM AUTHOR]