Awareness of both global uncertainty and feedback in human time estimation

Recent behavioral studies have shown that humans possess self-awareness of their individual timing ability in that they can discern the direction of their timing error. However, in these studies which included a single repeat (re-do) trial for each duration, it remains unclear whether the reduction in errors in the Re-do trials was due to self-awareness of individual timing ability or because the participants used the feedback from the initial trials to improve on the re-do ones. To investigate this further, we conducted a behavioral study in which subjects were divided into two groups: one in which the “Re-do” phase occurred frequently, but not always (80% of trials; called the “high double” group), and one in which Re-do trials were rare (20% of trials; called the “low double” group). This was done to test the possibility of subjects relying on the Re-do trials as a method of improvement. Subjects significantly improved in their performance on Re-do trials regardless of whether re-dos were rare or frequent. Further, an unexpected finding was observed, where subjects in the low double group also overall performed better than those in the high double group. This finding suggests that subjects, knowing that re-do opportunities were rare, engaged better timing at the outset; yet, these subjects still improved on Re-do trials, suggesting humans are able to incorporate both global uncertainty and feedback.