What factors underlie our experience of the passage of time? Theoretical consequences.

The aim of this study was to examine the factors that explain variations in the conscious experience of time. The level of difficulty of the task, emotional valence and duration of stimuli were tested in three different experiments with two ranges of durations, one of seconds and the other one of minutes. The results showed that the passage of time was judged faster with durations in the seconds than in the minutes range. However, for all duration values, each change in the features of the task produced changes in the judgment of the passage of time. The subjective feeling of an acceleration of the passage of time, therefore, increased linearly with the increase in the level of difficulty of the task and with the positive valence of the emotional stimuli. It also varied linearly with the length of real time, increasing in the same proportion as the decrease in stimulus duration, regardless of the associated range (seconds or minutes). Our theory is that the judgment of the passage of time might be a generic way of describing the most salient internal or external contextual changes experienced.