Decision-making processes in the Prisoner’s Dilemma Game uncover neural complexity linked to cognitive load and nonlinear neural dynamics

Elucidating the neural mechanisms underlying decision-making in complex social interactions hinges on resolving the nonlinear dynamic properties of collaborative brain network operations and their relationship with cognitive load. To this end, this study investigated the nonlinear dynamic characteristics of decision-making processes by quantifying the complexity of Electroencephalogram (EEG) signals during the Prisoner’s Dilemma game using multivariate multiscale entropy (mMSE). The results demonstrated that task-positive networks, particularly the Dorsal Attention Network (DAN) and Ventral Attention Network (VAN), exhibited higher complexity, which is associated with the heavier cognitive load of the brain in the process of rapid local information processing and global information integration during decision-making. The elevated complexities exhibited in performing Tit-for-Tat (TFT) strategy and making cooperative decisions, as higher cognitive load demanding tasks, confirm that mMSE can effectively quantify neural activity related to decision-making and feasibly depict the variations of EEG complexity corresponding to cognitive load, thus revealing the nonlinear dynamic neural mechanisms underlying the gaming process.