Why Do Actions in Slow Motion Appear to Last Longer? On the Effect of Video Speed Information

Abstract

When displayed in slow motion, actions are often perceived longer compared with original speed. However, it remains to be determined why this bias exists. Is it possible that the bias emerges because participants underestimate the factor by which a video was slowed down and hence arrive at erroneous conclusions about the original duration? If true, providing explicit information about the respective video speed should eliminate this slow motion effect. To scrutinize the nature of this bias, participants rated the original duration of sports actions displayed at original speed or slow motion. Results revealed the expected overestimation bias consisting in longer ratings with increasing slow motion. However, the bias disappeared when information about the current video speed was provided. The observations suggest an influence of knowledge about video playback speed on cognitive-evaluative processes which may hold important implications for future research and practice.

Slow motion bias: Exploring the relation between time overestimation and increased perceived intentionality

“…Note that, in the current study, and likewise in Caruso et al (2016), this might also represent a methodological issue since both measures are simultaneously inquired potentially suggesting participants to rate them similarly. Given that information on the slow motion factor did not reduce the intentionality bias as it did for absolute time (Sperl et al, 2021), and that there was no association between absolute time and intentionality ratings, we argue that two different systems of time processing might be involved, which will be discussed below. Potentially, intentionality ratings depend on relative rather than absolute time ratings (see also, Caruso et al, 2016).…”

“…Specifically, while slow motion is providing the observer with many apparent action alternatives, in the real life situation, this variety of options was often simply not at disposition for the actor in their perception of time. 2 Relating these findings to the observations from our recent study (Sperl et al, 2021), a fundamental question arises: That is, may providing video speed information not only be able to eliminate the time overestimation bias but also reduce the undesired impression of increased intentionality? In other words, if-following the rationale by Caruso et al (2016)-the increased perception of intentionality of an action is really caused by an overestimation of the time this action took, then, in line with our recent findings (Sperl et al, 2021), providing participants with explicit video speed information when watching actions in slow motion should not only counteract the overestimation of original time but also eliminate the undesired intentionality bias.…”

“…The core methodology followed that already used in Sperl et al (2021) including a set of necessary adjustments (most of them addressing the stimulus material and the new dependent variable in this study).…”

“…Sample Size: To determine an appropriate sample size, a power analysis was conducted with G * Power 3.1.9.7. Thanks to our previous study which followed a highly similar design using the same stimuli and general set-up, we were able to base our parameter settings for this analysis on existing empirical data: As outlined above, in that previous study (Sperl et al, 2021), participants were asked to estimate the duration of different sport actions presented in different video speeds by providing absolute time ratings in seconds. Following the reasoning by Caruso et al (2016) that the overestimation of perceived intentionality derives (primarily) from the overestimation of time, the expected effect sizes for the perceived intentionality and relative time rating (main task) should be comparable to the effect size of the time overestimation.…”

“…Analyses With Full Sample Size. As the time overestimation effect from our previous study for absolute time estimation (Sperl et al, 2021) could not be replicated in the preregistered sample, we repeated the analyses with the entire number of subjects who participated in this experiment (total: N = 102; uninformed group: N = 46; informed group: N = 56; absolute time estimation: N = 45; slow motion factor estimation: N = 57). Again, no participant had to be excluded for not detecting more than 50% of the foul play, and overall, only 15.8% of the foul plays could not be identified.…”