Arousal-Driven Serial Dependence: The role of Internal States in Temporal Judgments

Emotional experiences shape not only how we perceive the present but also how recent experiences inform our current judgments. This study examined whether emotional arousal and valence modulate serial dependence in time perception—the tendency for prior stimuli to bias ongoing estimates. Participants viewed affective images that induced high-arousal (positive or negative) or low-arousal (neutral) states and then reproduced each image’s duration. High arousal reliably lengthened perceived durations. More critically, it strengthened serial dependence, with the strongest biases emerging when high-arousal trials followed other high-arousal trials, showing a state-dependent amplification of temporal integration. Emotional valence, by contrast, exerted no measurable influence on either temporal distortion or sequential bias. These findings show that emotional arousal tunes how the brain weighs past against present, highlighting internal emotional states as a key driver of temporal continuity in perception.