Task-specific theta enhancement and domain-general alpha/beta suppression as oscillatory signatures of individual differences in 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 (WMC), underscoring the distinctiveness of cognitive flexibility from general cognitive abilities. These findings provide the first direct evidence that alpha/beta suppression constitutes a reliable, generalizable neural signature of individual differences in cognitive flexibility.