With the power of the inner eyes: the late positive potential during mental time travel through positive and negative experiences. An event-related potential study

Mental time travel involves mental imagery to recollect past experiences and envision future events, eliciting anticipatory emotional responses that motivate goal-directed behaviour. However, the temporal dynamics of neural, physiological, and affective processing of mental time travel remain elusive. This study examined late positive potential (LPP), skin conductance responses (SCR), and behavioural affect ratings in response to mental time travel. Forty-eight participants (52% female) viewed 16 neutral, positive, and negative stimuli from the International Affective Picture System ("encoding task"). Participants then vividly imagined the stimuli ("recall task") and imagined a scenario involving the presented stimuli as if it might occur after leaving the lab ("prospection task"). Results showed enhanced LPP amplitudes when recalling negative and prospecting positive experiences, alongside elevated self-reported affect and arousal during these emotional recall and prospection tasks. These findings suggest that mental time travel through emotionally salient events is associated with increased LPP amplitudes akin to the processing of immediate experiences. This might reflect a neural mechanism of anticipatory affective responses to mental representations.