Identifying Cognitive Resources in a Decision-Making during Gambling

Abstract In the learning stage of reward processing, the presence of an event-related potential (ERP) denoted as the Feedback-Related Negativity (FRN) is vastly mentioned which is elicited 200–350 milliseconds after feedback onset. Previous studies have confirmed Reinforcement Learning theory's prediction that a significant correlation exists between dopamine neuron responses (which generate the FRN) and the disparity between actual and expected outcomes where the expected outcome is determined by the probability and magnitude of rewards. Although previous studies have extensively illustrated the impact of reward probability on the FRN, the demonstration of the impact of reward magnitude on the FRN has not been established conclusively and still remains a matter of debate. Here in this study, we wanted to assess the effects that reward magnitude has on the FRN and its generator(s) as well in an isolated context. We recruited 24 participants and recorded 65-channel High-Density EEG signals with simultaneous fMRI, while they engaged in a modified task designed to control reward probability and evaluate the effects of reward magnitude. In our findings, firstly, a substantial positive correlation is observed between the ERP amplitude within the temporal window of FRN and the magnitude of outcomes, and through dipole fitting and distributed source localization, the source of FRN, regardless of magnitude, was located in the Medial Frontal Cortex. Our findings reveal strong connections among brain regions involved in error monitoring, memory, attention, and visual processing, with the dorsal Anterior Cingulate Cortex serving as a central hub. No significant differences were found between connectivity of win- and loss-related FRN’s brain sources. Additionally, participants demonstrated varying risk-taking behaviors across trials, favoring higher-risk options and transitioning towards more cautious decisions over consecutive trials during the experiment. The analysis also revealed increased risk-taking following losses compared to gains, highlighting contextual influences on decision-making.