Arousal contribution on valence-driven affective modulations of time perception

Emotional stimuli distort time perception, but whether these effects are driven primarily by arousal or depend critically on emotional valence remains unclear. To fill this gap, here we conducted two experiments investigating how emotional valence and physiological arousal contribute to temporal distortions across multiple timing tasks and temporal scales. Both experiments employed immersive emotional video clips (positive, negative, neutral) combined with physiological recordings (electrocardiography, electrodermal activity) and three timing tasks: finger tapping (sub-second range), time production (one minute), and retrospective duration judgment (several minutes). In Experiment 1 we employed a within-subjects design (N = 41), while Experiment 2 we adopted a between-subjects approach (N = 38) to control for carryover effects. Subjective ratings confirmed successful emotional manipulation across both experiments. Emotional videos consistently accelerated motor timing in the finger-tapping task regardless of valence. However, valence-specific effects on time production emerged only under specific presentation orders in Experiment 1, with positive stimuli shortening and negative stimuli lengthening perceived duration. Retrospective judgments remained largely unaffected. Skin conductance responses showed sustained activation following emotional stimuli, whereas heart rate changes were inconsistent. Our results indicate that emotional influences on time perception are selective, task-dependent, and highly sensitive to contextual factors including stimulus order and prior emotional exposure. These findings challenge purely arousal-driven models and suggest that temporal distortions emerge from dynamic interactions between affective appraisal, attentional engagement, motor readiness, and emotional history. The dissociation between prospective and retrospective timing highlights the importance of attentional allocation in emotion-induced temporal distortions.