Abstract
Previous results indicate that the rate of change within some stimulus dimensions (e.g., luminance) reliably influences subjects' reports of stimulus duration: for example, rapid rates of change result in overestimated event duration. What remains unclear, however, is the degree to which these bottom-up influences on behavior reflect distortion in the perception of time passing, rather than distortion in retrieval from short-term memory (STM). Specifically, when subjects must either compare the durations of successive stimuli or reproduce stimulus duration – two common experimental paradigms – they may need to “replay” stimuli held in STM. Furthermore, replaying stimuli from STM may take longer for more rapidly changing stimuli, resulting in overestimated duration. Two experiments reported here minimized the need for subjects to hold stimulus durations in STM. The results provide evidence for online, visually-evoked distortions in time perception. However, in subsequent studies we found that distortions in time perception were not tied to absolute rates of change; stimuli with identical rates of change were judged to have different subjective durations depending on context and subjects' expectations. These findings indicate that distortions in time perception arise from an interaction between bottom-up and top-down influences.