The oscillatory dynamics of medial frontal EEG theta and posterior alpha are implicated in the modulation of attention and cognitive control. We used a novel saccade cueing paradigm to examine whether theta and alpha are modulated by task difficulty during response preparation. After isolating and functionally classifying medial frontal and posterior alpha independent components, the EEG spectral power in these components was calculated on pro- and anti-saccade trials prior to response probes. The results of bootstrap re-sampling show that, compared to pro-saccade trials, correct anti-saccades are characterized by an increase in medial frontal theta and suppression of posterior alpha during the response preparation period. Furthermore, an absence of increased medial frontal theta prior to anti-saccades probes occurs on error trials, that is, a failure to control pre-potent eye movements. For these error trials, a burst in medial frontal theta is instead observed following error feedback. Our findings show that enhanced medial frontal theta is linked not only to dynamic cognitive control that is reactive (such as, after error commission), but is also an important prerequisite for success when behavioral control is challenged.
Keywords: Independent components analysis; Medial frontal cortex; Performance monitoring; Robust estimation; Saccades; Theta.
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