Cite as:
Verstraten F A J, Kanai R, Hogendoorn H, Paffen C L E, 2005, "Visual motion expands perceived time" Perception 34 ECVP Abstract Supplement

Visual motion expands perceived time

F A J Verstraten, R Kanai, H Hogendoorn, C L E Paffen

It has been proposed that perceived duration is based on the total number of events experienced by observers. In the present study, we investigated how visual motion--a form of change in the visual modality--affects perceived duration. For a target stimulus, we used a square moving with a variable speed (0 to 48 deg s^-1) for a variable duration (0.2 to 1.0 s). We found that the perceived duration of motion increased with increasing speed; at high speeds, magnitude of the effect increased up to an overestimation by 250 ms and then saturated. However, the overestimation of duration was not determined by the speed alone; it also depended on stimulus duration. With longer presentation times, time dilation was attenuated. Next, we examined whether the magnitude of time dilation depends on perceived or physical speed. In order to dissociate perceived and physical speeds, we ran an experiment using low-contrast and isoluminant stimuli and compared the results with those obtained with high-contrast stimuli. Both types of stimuli tested are generally perceived to move slower than high-contrast stimuli. We found that time dilation for perceptually slow-moving stimuli shows the same speed-duration dependence as that for high-contrast stimuli. This indicates that time dilation is determined by the physical aspects of the stimulus and not by its perceived speed. In sum, we show that perceived duration of visual motion depends on both its speed and duration. Fast speeds appear to last longer than slow speeds. Also, time dilation is larger when physical presentation of motion is short than when it is longer. In conclusion, time dilation is independent of perceived speed, which makes it tempting to suggest that there are separate processes for time and speed perception.

[Supported by the Netherlands Organisation for Scientific Research.]

These web-based abstracts are provided for ease of seaching and access, but certain aspects (such as as mathematics) may not appear in their optimum form. For the final published version of this abstract, please see
ECVP 2005 Abstract Supplement (complete) size: 2356 Kb