Assessing the roles of subjective value and valence in outcome evaluation for consumer products: evidence from behavioral and electrophysiological experiments

Value-based decision-making is ubiquitous in our daily lives, yet most EEG studies focus on monetary outcomes, with limited attention to how the brain encodes the subjective value and valence of consumer products during outcome evaluation. To address these questions, we set up a novel three-stage task to investigate the behavioral regularities of recall of valence for food products with varying subjective values and their underlying electrophysiological mechanisms for subjective valuation and valence differentiation. With respect to the event-related potential results, we found that not receiving the food products (No-Gain) led to an increase in the FRN. Regarding the P300, we found that both higher subjective values and positive feedback elicited greater deflection of P300 at the outcome stage. Intriguingly, further single-trial analysis of EEG demonstrated that the magnitude of P300, rather than the FRN at the outcome stage, could predict subsequent behavioral performance as represented by memory accuracy. Therefore, these findings highlight the vital and dissociated roles of FRN and P300 in the subjective valuation of consumer products and suggest the possible role of P300 as a biomarker to predict subsequent choice behavior.