Task-specific theta enhancement and domain-general alpha/beta suppression as oscillatory signatures of cognitive flexibility.

Cognitive flexibility-the ability to adapt to changing situational or task demands-is a fundamental aspect of human cognition and a potential source of individual differences in higher-order cognitive abilities. To further understand the neural mechanisms underlying this ability, we examined event-related spectral perturbations (ERSP) in three cued switching tasks (parity/magnitude, global/local, number/letter) in a sample of 148 adults. Employing a data-driven approach that combined mass-univariate time-frequency analysis, cluster-based permutation testing, and latent change structural equation modeling, we identified two robust neural signatures: a transient frontal theta increase and a sustained alpha/beta suppression. Both effects were more pronounced in switch compared to repeat trials. Frontal theta reflected task-specific control processes, whereas parietal alpha/beta indexed domain-general attentional processes that persisted from cue onset through target processing-consistent with two-stage models of task switching. Notably, flexibility-related alpha/beta dynamics did not correlate with measures of intelligence or working memory capacity. However, stronger cue-elicited alpha/beta suppression correlated with reduced non-decision-time switch costs, indicating more effective task preparation, underscoring that alpha/beta suppression captures a neurally coherent but behaviorally distinct dimension of cognitive flexibility. These findings provide evidence that alpha/beta suppression constitutes a reliable, cross-task generalizable neural signature of attentional reconfiguration during task switching, while highlighting the multi-component nature of individual differences in cognitive flexibility.