Abstract
Time appears to pass in slow motion, according to subjective reports of people who have been involved in car accidents or other extreme situations. Previous research attributed time’s subjective expansion (TSE) to the engagement of attention and its influence on the amount of perceptual information processed (Tse et al., 2004). We propose that two processes contribute to slow motion perception in TSE. One is grouping attributes of the scene into wholes and segregating them from their background. Another is an increased amount of attention to temporal properties of the extreme scene. The present thesis investigates the influence of visual grouping and temporal attention on temporal resolution in a less dramatic situation to reveal whether novel or important events perceived in slow motion may indeed be processed in greater depth per unit of objective time than are normal events as assumed by Tse et al. (2004). A temporal order judgment (TOJ) task was applied at 50 participants to measure temporal resolution. A grouping effect was induced by use of a bar stimulus to unify the background on which two light-emitting diodes (LEDs) flashed. Two squares, one forming the background of each separate LED, comprised a control condition for the unified one just described. Attention to temporal properties of the background stimuli was induced by the use of abrupt stimuli which appeared with a specific temporal interval prior to the onset of either LED. In the control condition, the background stimuli were displayed persistently throughout the whole trial rather than abruptly.
Temporal resolution was significantly higher when either visual grouping or temporal attention induced by abrupt stimuli was present and highest when both were combined. This novel finding provides evidence that multiple processes are involved leading to increased temporal resolution during TSE.