Page 100 - It' about time: Studying the Encoding of Duration
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                                100 80 60 40 20 0 -20 x Representing dynamic stimulus information during occlusion                                          -20 0 20 40 60 80 100 Expectancy Effect, Non-Ocluded Figure 6. Scatterplot plotting the percentage of Time dilation that results from the difference in expected temporal frequency (Expectancy effect, %), for the Non-Occluded (x-axis) and Occluded (y-axis) conditions. Each open circle represents an individual participant. The x indicates an outlier (deviation >2*std), which was not included in the analysis. The dotted line indicates the regression line while the solid line represents the unity line. General discussion In this study we investigated whether dynamic stimulus information is represented during occlusion. To answer this question we used a well-known temporal illusion (temporal frequency induced time dilation) in which the 5 perceived duration of a stimulus increases with an increase in temporal frequency content. We combined this illusion with a situation of stimulus occlusion to probe the representation of temporal frequency during occlusion. We hypothesized that if temporal frequency content is represented during occlusion it should affect judgments of duration made for temporarily occluded stimuli. To test this hypothesis we conducted two experiments. In the first experiment, participants reproduced the duration of a stimulus that was either static or luminance-modulated (5 Hz, 10 Hz). During each presentation the stimulus either remained visible (Non-Occluded) or became temporarily occluded (Occluded). In a third, control condition (Extinction), the stimulus remained visible but its luminance modulation temporarily faded out, mimicking the loss of temporal frequency information in the occluded condition. This allowed us to dissociate between time dilation as a results of pre- and post- occlusion presentation of the stimulus and time dilation occurring  99 Expectancy Effect, Occluded 


































































































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