Temporal judgments on intervals containing stimuli of varying quantity, complexity and periodicity

The ‘attentional’ model of psychological time predicts an inverse relationship between nontemporal information processing and subjective duration in the second or minute range. To produce this effect, periodically presented stimuli of varying quantity and/or complexity have generally been used. However, the possible effect of the periodic distribution of stimuli has been overshadowed. The present experiment was meant to manipulate simultaneously regularity, quantity and complexity in a dual-task paradigm involving both word categorization and reproduction of duration (18 s) under prospective conditions. The results indicate that (1) and aperiodic stimulus distribution elicits shorter temporal reproductions than a periodic distribution, (2) the smallest quantity of stimuli elicits the shortest temporal reproductions, and (3) an increase in the stimulus complexity generally elicits a shortening in temporal reproductions, but changes in processing strategies may counteract this effect.