From truth to deception: a network control theory perspective on brain connectivity and cognitive dynamics

Deception represents a sophisticated mental activity that modifies the brain's dynamic operations. Understanding how brain activity changes during deceptive behavior is important for both cognitive neuroscience and practical applications such as lie detection. Recently, network control theory (NCT) has emerged as a novel tool that combines principles from network science and control theory, offering a powerful framework for quantifying how easily the brain can transition between different cognitive states. In this study, NCT is applied for the first time to examine the effects of deception on brain functional connectivity (FC). Electroencephalogram signals are recorded from 22 participants during a visual task designed to elicit deception. The phase lag index method is then employed to construct FC networks for both truthful and deceptive conditions. The brain is modeled as a linear dynamical system, and two control metrics, average controllability and modal controllability, are computed across five frequency bands: delta, theta, alpha, beta, and gamma. The results reveal significant differences in brain dynamics between the two conditions. In the delta and beta bands, average controllability is significantly higher during truthful responses (p-value < 0.005), while in the gamma band, it is elevated during deception. Additionally, in the beta and gamma bands, modal controllability is significantly higher during deceptive responses (p-value < 0.005). It is observed that during deception, the control energy spectrum shifts from predominance in lower frequencies, which is more evident in truthful responses, toward higher frequencies where energy increases during deception. The outcomes imply that brain connectivity patterns are affected by deceptive behavior and highlight the potential of NCT in advancing deception-related investigations.