Motivational intensity in positive emotion and observation-based false memory: the role of action simulation.

Positive emotion has been linked to increased false memory, yet most research has focused on emotional valence and arousal, leaving the role of emotional motivation unclear. Using an ecologically valid observation-inflation paradigm, the present study examined whether variation in approach-motivated positive emotion relates to action-based false memories arising from observing others' behavior. In Experiment 1, participants were induced into either high or low approach-motivated positive emotional states before completing the task. Both states increased misattributions of observed actions to the self, but the effect was stronger under high approach-motivated positive emotion, suggesting that motivational intensity is associated with variation in observation-based memory distortion. Experiment 2 introduced imitation-inhibition training to reduce motor simulation during action observation. Participants who received this training showed a reduced observation-inflation effect, suggesting that motor simulation contributes to observation-based false memory. Together, these findings indicate that variation in motivational intensity within positive emotion is associated with differences in how observed actions are incorporated into episodic memory.