Abstract
This study investigated whether honesty is a stable trait or varies depending on situational factors. Using a coin flip guessing paradigm with monetary rewards, 33 participants completed trials with rewards ranging from 0.01 to 3 yuan. Modeling of behavioral data showed individuals have varying "honesty thresholds" where they switch from honest to dishonest behavior. EEG analysis revealed increased P300 amplitude when resisting greater monetary temptation, and individuals with higher honesty thresholds had lower P300 amplitudes for the same rewards. A late positive component indicated greater cognitive conflict when the reward amount neared an individual's honesty threshold. These findings challenge the conception of honesty as a stable trait, instead demonstrating it varies based on contextual factors like reward size. Computational modeling and EEG provide insight into the cognitive processes underlying contextual shifts in honest behavior.